39
Chapter 4
Regional and Circumpolar Levels and Trends
in Abiotic and Biotic Media
This section reviews new information on the levels and
giving the concentration of OC in the total weight of tis-
spatial trends of POPs in Arctic abiotic and biotic media
sue analyzed; on a lipid weight basis, giving the concen-
available since 1996. Some earlier data which were omit-
tration in the lipids in that particular tissue; or as a body
ted from the previous assessment are also included. Most
burden, giving the contaminant concentration in the
interpretations in this chapter, including comparisons and
whole organism. OC levels in abiotic samples and some
conclusions about spatial trends, were made by scientists
biotic samples, most often plants, are expressed on a dry
in charge of projects described (most are listed as con-
weight basis. The following abbreviations are used
tributing authors) and by the four editors. In some cases
throughout the text to distinguish lipid weight concen-
interpretation was not possible due to limited sample
trations (that is `ng/g lw'), from results reported on a wet
numbers. The new data are primarily entered as summary
weight (`ww') or dry weight (`dw') basis. All lipid weight
data in the Annex Tables, and interpretations were kept
concentrations are calculated from the wet weight con-
to a minimum. It should also be noted that sample sizes
centrations unless otherwise indicated. Concentrations
for results given in the Annex Tables vary greatly. Readers
of OCs in air samples expressed as pg/m3 are presented
should be aware of the risk of spurious conclusions
for gas phase and particle phase separately or are
drawn from small data sets. Within the AMAP monitor-
summed to give a total air concentration. Fluxes of OCs
ing program, QA/QC criteria have been defined, and
in sediments are expressed as ng/m2/yr (i.e. concentra-
these have been followed by almost all laboratories that
tion in ng/g
sedimentation rate g/m2/yr).
have contributed data to the assessment. All laboratories
providing data within their national monitoring programs
have also taken part in intercalibration exercises. There-
4.1. Atmospheric environment
fore, the data presented here are comparable across labo-
4.1.1. Air
ratories. The only major exceptions occur when varying
4.1.1.1. Introduction
numbers of congeners have been analyzed and quantified.
This is most prevalent for PCBs and toxaphene, both of
Measurements of POPs in Arctic air have continued on a
which have been reported as differing numbers of con-
weekly basis at locations in Canada, Iceland, Norway,
geners as well as total sums based on quantification
Finland, and Russia, building on the datasets discussed
against a technical product (total PCB, total toxaphene).
in the first assessment. In addition, over the past five
Readers are also reminded that concentrations are
years, a number of ship-based studies have also meas-
expressed in several ways in this report. In biological sam-
ured air concentrations of POPs over shorter time peri-
ples concentrations are expressed on a wet weight basis,
ods to address airwater exchange.
1. 60°20'N, 134°12'E
1. 74°60'N, 124°30'E
2. 2200 m
2. Sea level
3. Forested, near local sources
3. Remote, treeless,
(e.g., wood smoke
Lena River Delta near Arctic Ocean
and air from N Pacific Ocean
4. 1993. No longer operating
4. 1992-1995. No longer operating
Tagish
5. Chlorinated pesticides, PCBs, and PAHs
5. Chlorinated pesticides, PCBs and PAHs
6. Weekly
6. Weekly
Dunai
Alert
1. 69°43'N, 61°37'E
1. 82°30'N, 62°20'E
2. Sea level
2. 200 m
Amderma
Ny-Ålesund
3. Forested, near military bases
3. Remote, treeless,
and Pechora Sea
near military base (Alert)
Pallas
4. 1999-2000. Possible future operations
and Arctic Ocean
Stórhöfdi
5. Chlorinated pesticides, PCBs, and PAHs
4. 1992-1998. Monitoring continues
6. Weekly
5. Chlorinated pesticides, PCBs, and PAHs
6. Weekly
1. 63°24'N, 20°17'W
1. 68°00'N, 24°15'E
2. Sea level
1. 78°09'N, 11°09'E
2. 340 m
3. Remote, air from NW Atlantic Ocean
2. 475 m (Zeppelin Mountain)
3. Forested, remote, on the top of a small hill
4. 1995-1999. Monitoring continues
3. Remote, treeless, near research base
4. 1996-1999. Monitoring continues
5. Chlorinated pesticides and PCBs
(Ny-Ålesund) and Barents Sea
5. Chlorinated pesticides, PCBs, and PAHs
6. Weekly
4. 1992-1998. Monitoring continues
6. One week/month, air+ deposition
5. Chlorinated pesticides, PCBs, and PAHs
6. Weekly
Figure 4·1. Locations and site-specific information for each POPs air monitoring station. 1. Latitude/longitude; 2. Elevation; 3. Description;
4. Sampling period and status as of 2002 (this is the total operational period for which data were available for this assessment. Sampling pe-
riod varies with chemicals measured); 5. POPs monitored; 6. Sampling schedule.
86
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Concentration
Concentration
a Octachlorostyrene
b Pentachlorobenzene
in bottom sediment, ng/g dw
in bottom sediment, ng/g dw
0.10
0.5
0.4
Honningsvåg
0.3
Hammerfest
0.05
0.2
Tromsø
Guba Pechenga
0
0.1
N O R W A Y
Murmansk/
Harstad
0
Kola Bay
200 km
R U S S I A
Concentration
Concentration
c DDTs
d
in bottom sediment, ng/g dw
PCB7
in bottom sediment, ng/g dw
5
100
4
3
2
1
50
0
0
Figure 4·35. Geometric mean concentrations of octachlorostyrene, pentachlorobenzene, DDT, and PCB7 in bottom sediments of some
harbors of northern Norway and the Kola Peninsula. DDT = p,p'-DDE + p,p'-DDD + p,p'-DDT; PCB7 = CB28 + CB52 + CB101 + CB118
+ CB138 + CB153 + CB180.
The highest concentration of PCB7 was found in
ate concentrations in Guba Zapadnaya Litsa (19-95 ng/g
the harbors of Harstad, Hammerfest, and the Murmansk
dw). This was the first report of toxaphene in marine
area of Kola Bay (Figure 4 ·35). Detailed results are pre-
sediments in the European Arctic and it suggests use
sented in Annex Table 9. All these harbors had PCB con-
and/or spills in the harbor area of Polamyy north of
centrations, which according to guidelines from Norwe-
Murmansk.
gian State Pollution Control Authority (SFT) (Molvær et
Savinov et al. (2003) reported OCs in sediments col-
al., 1997) are classified as `strongly polluted'. In all the
lected in 1997 in Guba Pechenga and adjacent marine
harbors, locations were found having DDT concentra-
coastal areas: Varangerfjord, Guba Malaya Volokovaya,
tions classified as `strongly polluted'. The concentrations
and Guba Bol'shaya Volokovaya on the western Kola
of pentachlorobenzene and OCS were also elevated in all
Peninsula. Slightly elevated DDT concentrations (37
the harbors compared to previous reports for background
ng/g dw) were found in Liinakhamari harbor in Guba
areas at offshore locations (de March et al., 1998).
Pechenga and a high DDT: DDE ratio (23.4) indicated a
There were also statistically significant differences
possible local DDT source in this area. However, the
(p < 0.05) between the distributions of HCB and HCHs
overall average DDT levels in Guba Pechenga sedi-
in the six harbors. For OCS, Harstad harbor was signi-
ments were comparable with those in harbor sediments
ficantly different from the four others (no data from
of northern Norway (Dahle et al., 2000) and outer Kola
Kola Bay), and for pentachlorobenzene, both Harstad
Bay (Savinova et al., 2000a). PCB concentrations in Guba
and Pechenga were significantly different compared to
Pechenga were slightly elevated in Liinakhamari harbor
the other four harbors. For DDTs, Tromsø had a sig-
as well. However, overall values was significantly lower
nificantly different pattern, and for PCB7, the most
in comparison with those found in harbors of the north-
polluted harbors (Harstad, Hammerfest, Honningsvåg,
ern Norway and Kola Bay (Dahle et al., 2000; Savinova
and Kola Bay) comprised a homogeneous group differ-
et al., 2000a)
ent from the two others (Figure 4 ·35).
The studies of harbors in northern Norway and
In sediments from all these harbors and also from
northwestern Russia indicate that harbors may be `hot
Honningsvåg and Kola Bay areas, the higher chlorinated
spots' for contaminants in the Arctic. Steps need to be
CBs predominated in samples where the highest PCB7
taken to understand the extent of the pollution in the
concentrations were found. Only sediments from Guba
harbors, the potential for spreading to adjacent waters
Pechenga with maximum PCB7 levels had high per-
including the Barents Sea, and the impact on regional
centages of lower chlorinated CBs.
fauna.
Savinova et al. (2000a) analyzed samples collected in
Analysis of a sediment core from the profundal area
1997 from Kola Bay and Guba Zapadnaya Litsa on the
of Kandalashka Bay in the White Sea revealed relatively
western Kola Peninsula. In general, levels of OCs were
low levels of persistent OCs (Annex Table 9). Maximum
similar to those reported by Dahle et al. (2000). How-
concentrations of most OCs were found in deeper layers
ever, high concentrations of toxaphene were found at lo-
indicating greater inputs in the recent past (Muir et al.,
cations in Kola Bay (up to 681 ng/g dw) and intermedi-
2002a). PCB concentrations were higher than back-
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
87
ground locations in the southwest Barents Sea (Savinov
affins and PBDEs (Stern and Lockhart, 2001). Concen-
et al., 2003) but lower than in Kola Bay and Guba Za-
trations of the major OC groups were lower than reported
padnaya Litsa.
previously for Hudson Bay surface sediments taken from
a core (Lockhart, 1997). A generally decreasing trend
Kara and Laptev Seas
from south to north and from east to west is apparent
Sericano et al. (2001) reported POPs in surficial sedi-
from the results, although this could be influenced by
ments from the southern Kara Sea adjacent to the Ob
variation in sedimentation rates (Figure 4 ·36).
and Yenisey. The samples were collected in 1993. How-
PCB concentrations in the sediments from the ar-
ever, results were not available for the previous AMAP
chipelago waters ranged from 0.3 to 2.9 ng/g dw. These
POPs assessment. DDT and PCB concentrations in
are at the low end of the range for marine sediments
sediments ranged from < 0.1 to 1.2 ng/g dw and < 0.1 to
found in the previous AMAP POPs assessment (de
1.5 ng/g dw, respectively. Chlordane compounds were
March et al., 1998). DDT and total chlordane-related
not detected (< 0.1 ng/g dw). Despite the low levels, a
compounds were present at extremely low levels (0.04-
distinct distribution pattern was observed with higher
0.44 ng/g dw). SCCP concentrations in the surface sedi-
concentrations in the lower part of the Yenisey below
ments ranged from 4.8 to 77.4 ng/g dw and were among
the salt wedge. The concentrations of DDTs and
the predominant OC compounds in these sediments. As
PCBs in marine sediments were within the range re-
with the OC pesticides and PCBs, a decreasing trend in
ported previously for the Ob and Yenisey Gulf (0.03 - 0.8
SCCP concentrations was observed from southern
ng/g dw and 0.01- 2.2 ng/g dw, respectively) (Vlasov and
(Barrow Strait) to northern (Peary Channel) and west-
Melnikov, 1995, in de March et al., 1998).
ern Arctic (M'Clure Strait/Viscount Melville). Sediment
Relatively high proportions of p,p'-DDT and o,p'-
concentrations were lower than in the eastern Arctic
DDT in sediments suggested local or fresh sources of
(Strathcona Sound/Lancaster Sound) sediments (Annex
DDT at the time of sample collection (1993). The PCB
Table 9; Figure 4 ·36).
homologue profile in the sediments was dominated by
Pe- and HxCBs, suggesting local or nearby sources of
4.4.3. Marine phytoplankton and invertebrates
PCBs to the Kara Sea.
Utschakowski (1998) determined PCBs in surface
Marine invertebrates provide a link between phyto-
sediment samples collected in 1993 from the southern
plankton and fish/seabirds/mammals in Arctic marine
Laptev Sea offshore of the Lena River Delta. PCB con-
food webs. They are important in the transfer of carbon
centrations averaged 0.53 ng/g dw (range 0.14-1.99 ng/g
and nutrients as well as POPs to upper trophic-level or-
dw) and were correlated with organic carbon content of
ganisms. An understanding of the trends and dynamics
the sediments (Annex Table 9).
of POPs in marine invertebrates is a key to understand-
ing the trends of POPs in Arctic marine ecosystems.
Canadian Arctic
A number of studies have been recently carried out to
In 1997 and 1998, sediment cores and grab samples
examine OC concentrations in marine invertebrates, an
were collected from various regions of the Canadian
area identified as a knowledge gap in the first AMAP as-
Arctic Archipelago including northern Baffin Bay (An-
sessment report. These studies covered a wide geograph-
nex Table 9). A number of these grab samples have been
ical area and have provided information on spatial trends.
analyzed for OC pesticides, PCBs, and current-use con-
There was also a single study on levels of OCs in plank-
taminants such as short-chain (C10- C13) chlorinated par-
ton, predominantly phytoplankton. Many of these stud-
80°N
Concentration in surface sediments
ng/g dw
5
50
4
40
3
30
2
20
1
10
0
0
SCCP
PCBs
Figure 4·36. PCB and SCCP con-
70°N
centrations in marine surface sedi-
ments from the Canadian Arctic
Archipelago (Stern and Lockhart,
2001).
90°W
88
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
ies were designed to examine factors that influence OC
PCB10 concentration
concentrations in these lower trophic-level organisms. A
in calanoid copepods, ng/g lw
30
large number of samples from single species, particularly
in zooplankton, were analyzed for OCs. In a number of
cases, these data were used in food web studies, dis-
cussed in Section 4.4.9.
20
In general, OC concentrations in marine phytoplank-
ton and invertebrates are low, consistent with their gen-
erally lower trophic levels and smaller body sizes. Inver-
10
tebrates that are longer-lived, larger-bodied or that scav-
enge have higher POP levels and are generally benthic.
Barrow
Phytoplankton
0
Marine samples were collected to the west of Bjørnøya
Holman
(74°22'N, 18°55'E) as part of a marine food web study
(Evenset et al., 2002). This work was part of the larger
study examining elevated levels in Ellasjøen (see Section
Hudson Bay
4.3.5). Twenty-three vertical hauls (net diameter 25 cm,
N Baffin Bay
mesh size 5 µm) were taken from 20 m depth to the sur-
N Svalbard
face. These samples were predominantly phytoplankton.
Barents
Greenland
Sea
Sea
Low concentrations of PCBs and pesticides (mostly
below detection limits for pesticides) were found in the
marine phytoplankton sample taken west of Bjørnøya
(Annex Table 10).
Zooplankton
A number of studies have examined OCs in pelagic zoo-
plankton. The most common OC compounds in pelagic
Figure 4·37. Concentrations of PCB10 in calanoid copepods from
Barrow, Alaska; Holman, NWT and Hudson Bay (Hoekstra et al.,
zooplankton are the more water-soluble compounds,
2002b); northern Baffin Bay (Fisk et al., 2001a); and regions
such as the HCH isomers and lower chlorinated PCB
around Svalbard (PCB9, Borgå et al., 2001).
congeners. This reflects the smaller size, lower trophic
level, and lack of biotransformation capacity generally
trophic-level organisms are much higher in the European
found in zooplankton as compared to fish, mammals,
compared to the North American Arctic. Thus, concen-
and birds.
trations found at the base of these two food webs cannot
explain the high POP levels seen in upper trophic-level
Spatial trends in calanoid copepods
organisms in the European Arctic compared to northern
OC concentrations were determined in calanoid cope-
Baffin Bay.
pod samples from a number of studies in the Beaufort
The low OC concentrations in the copepods from
Sea and Hudson Bay (Hoekstra et al., 2002b), northern
east (Greenland Sea) and north of Svalbard may be due
Baffin Bay (Fisk et al., 2001a), and in the ocean around
to timing of the sample collection, seasonal changes in
Svalbard (Borgå et al., 2001) (see Figure 4 ·37 for loca-
water concentrations of OCs, and/or the source of water
tions). Calanoid copepods are dominant components, in
in these locations. As a small organism, the copepod
terms of both number and biomass, in high-latitude ma-
could reflect subtle changes of OCs in water that a large
rine zooplankton communities, and play an important
organism would not. The source of water for these cope-
role in polar food webs, as their high lipid reservoirs and
pods would come predominantly from under the ice cap
biomass provide organisms at higher trophic levels with
to the north, which would explain, in part, the lower
a high-energy diet (Springer et al., 1996). Concentra-
concentration of OCs compared to the Barents Sea cope-
tions (lipid-normalized) of PCB10 (sum of ten con-
pods. The collection of the copepods from the east and
geners) in the Beaufort Sea samples were slightly lower
north of Svalbard also occurred in September and Octo-
than those in northern Baffin Bay and Hudson Bay,
ber after the open-water period. Hargrave et al. (2000)
which were similar (Figure 4 ·37). OC concentrations in
found that OC concentrations were highest in Arctic
the North American copepods were greater than those
zooplankton during periods of ice cover.
measured in oceans to the east (Greenland Sea) and
Concentrations of HCB and HCH isomers in the
north of Svalbard but lower than those observed to the
Beaufort Sea copepods were relatively higher than the
south of Svalbard (Barents Sea) (Figure 4 ·37). Similar
more easterly sampling locations. The abundance of
trends were seen with other OC groups including tox-
HCB and HCHs in Alaskan and western Canadian
aphene, DDTs, and CHLs. Levels of OCs were also
zooplankton reflects the long-range atmospheric trans-
higher in the northern Baffin Bay predatory amphipod,
port of the chemicals and geographic proximity to areas
Themisto libellula (Fisk et al., 2002a) compared with
of recent application in Asia (Li, 1999a; 1999b; Bailey et
the same species collected east and north of Svalbard
al., 2000). The concentrations of OC compounds in
(Borgå et al., 2001). These spatial trends do not agree
zooplankton samples, including Calanus hyperboreus,
with that observed in marine mammals (Muir et al.,
collected in the late 1980s in the Arctic Ocean were sim-
2000b) and some seabird species (Fisk et al., 2001b).
ilar to the Beaufort Sea values (Bidleman et al., 1989).
Concentrations of most OCs, excluding HCH, in upper
This suggests that OC concentrations in the western
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
89
Arctic zooplankton have remained constant during the
Factors influencing OC levels in zooplankton
1990s in the Beaufort Sea region.
The relative abundance of hydrophobic chemicals such
The ranking of OC group concentrations in the
as DDTs and CHLs in copepod samples of Alaska and
Alaskan and Canadian copepods from highest to lowest
Canada was greater than that observed in water (Fisk
were: toxaphene PCBs > HCHs > DDTs > CHLs
et al., 2001a; Hoekstra et al., 2002b), and reflects their
> CBz (Fisk et al., 2001a; Hoekstra et al., 2002b).
greater potential for bioaccumulation from the abiotic
There are no toxaphene data for the Barents Sea cope-
environment into marine zooplankton near the base of
pods, but the general ranking of OCs is similar, except
the food chain than less hydrophobic OCs. The relation-
for lower relative levels of HCHs (Borgå et al., 2001).
ships observed between the bioconcentration factor (BCF)
Recent work on mixed zooplankton from the west of
and Kow for the Beaufort Sea and northern Baffin Bay ca-
Bjørnøya found toxaphene to be the predominant OC
lanoid copepods were linear and near, but slightly higher
although at concentrations lower than PCBs (Annex
than, 1 :1 for OCs with a log Kow between 3 and 6, but
Table 10) (Evenset et al., 2002). The higher abundance
curvilinear when hydrophobic OCs (log Kow > 6) were
of toxaphene congeners relative to other OCs in North
included (Fisk et al., 2001a; Hoekstra et al., 2002b).
American zooplankton is consistent with OC concentra-
These results suggest that for hydrophobic OCs (log Kow
tions in zooplankton collected in the Arctic Ocean off-
3.8- 6.0) dietary accumulation may play a small role in
shore from Axel Heiberg Island in the Canadian Arctic
elevating OC levels above equilibrium in zooplankton.
(Bidleman et al., 1989). The - and -HCH isomers and
Studies of OC levels in zooplankton collected to the
lower chlorinated PCB congeners were the most com-
west of Bjørnøya found that zooplankton size was an
mon OCs found in the Arctic calanoid copepods.
important variable in OC concentrations (Evenset et al.,
2002). The concentrations in zooplankton seemed to in-
Levels in other zooplankton species
crease from small zooplankton (<1 mm, mainly cope-
OC data for a number of other pelagic zooplankton
pods) to larger zooplankton (>1 mm, mainly comb jel-
have been recently generated in northern Baffin Bay
(Fisk et al., 2001c; 2002a; Moisey et al., 2001) and the
B E N T H I C
P E L A G I C
Barents Sea region (Borgå et al., 2001; 2002b). A ma-
jority of these samples were analyzed as part of food
Concentration, ng/g lw
400
web studies, discussed in Section 4.4.9. Seven species of
HCHs
zooplankton were collected in northern Baffin Bay and
300
analyzed for OCs, including: C. hyperboreus (herbi-
vorous copepod, discussed above); Euchaeta glacialis
200
(omnivorous copepod); Metridia longa (omnivorous co-
pepod); Mysis occulata (detritus-feeding and predatory
100
mysid); Themisto libellula (predatory amphipod); Sagit-
0
ta sp. (predatory arrowworm); and Pandalus sp. (preda-
300
tory shrimp). Lipid content varied between species,
DDTs
ranging from 2.1 to 7.0%. OC concentrations (lipid cor-
250
rected) varied between species and appeared to be re-
200
lated, in part, to a combination of trophic position (as
150
determined by 15N) and body size (Figure 4 ·38). The
relative ranking of OC groups also varied with the
100
species.
50
In general, for these zooplankton species, PCB con-
0
centrations were highest and CBz concentrations were
1000
lowest. Borgå et al. (2001) measured OCs in the herbi-
PCBs
vorous pelagic copepod Calanus sp. (copepods), the her-
800
bivorous euphausiid Thysanoessa sp., and the preda-
600
cious pelagic crustacean Parathemisto libellula (amphi-
pod). OC concentrations were similar to those observed
400
in the northern Baffin Bay zooplankton.
200
Concentrations of PCBs (both as sum of 11 con-
geners and Aroclor 1254) were determined in mixed
0
sp.
sp.
zooplankton (Calanus sp., T. libellula, ctenophores, gas-
tropods) and shrimp (Pandalus borealis) collected in
Sagitta
1991 from various sites within the Barents Sea region
Anonyx nugax
Mytilus edulis
Mya truncata
Metridia longa
Pandalus
Mysis occulata
(Joiris et al., 1997). PCB levels were not related to lipid
Saduria entamon
Euchaeta glacialisThemisto libellula
Yoldia thraciaeformis
Calanus hyperboreus
levels of the zooplankton. Levels of PCB were higher in
Ctenodiscus crispatus
Gorgonocephalus arcticus
the shrimp samples compared to the mixed zooplankton
Figure 4·38. Concentrations of HCHs, DDTs, and PCBs in Arc-
using lipid corrected values, but lower when wet weight
tic benthic and pelagic invertebrates. All samples were collected in
concentrations were examined. Concentrations for both
4.4.3.2
1998 in northern Baffin Bay except M. truncata (1993 in Iqaluit
sample types did not vary between sites. Concentrations
harbor), M. edulis (1998 at seven locations in northern Quebec)
and S. entamon (1998 in northern Alaska near Barrow). Results of
were found to be lower than levels measured in similar
A. nugax and G. arcticus include samples from Cumberland Sound.
species from the Atlantic Ocean but higher than levels
All data from Fisk et al. (2002a). Bars are mean ± 1 SE; see Annex
observed in the Canadian Arctic.
Table 10 for sample numbers.
90
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
lies, arrow worms, and medusae) to larger crustaceans.
pounds (e.g., HCHs) did not differ by size-class (Borgå
The exception was PCBs, concentrations of which were
et al., 2002c).
highest in the zooplankton >1 mm.
To investigate the levels of OCs in sympagic (i.e. as-
Benthic marine invertebrates
sociated with ice edges) fauna, ice-associated amphipods
Benthic invertebrates have a larger range of sizes, feed-
were collected in the marginal ice zone north of Svalbard
ing ecology, and ecological niches than pelagic zoo-
and in the Fram Strait in September 1998 and 1999
plankton, and therefore, have a greater range of OC
(Borgå et al., 2002a; 2002b). Amphipods dominate the
concentrations (Fisk et al., 2002a). Scavenging benthic
sympagic fauna (Melnikov, 1997), and represent a direct
invertebrates have the potential to have very high OC
link between ice-algae and sympagic meiofauna and
concentrations. PCBs are the OC group with the greatest
higher trophic levels (Lønne and Gulliksen, 1989; Lønne
concentrations in benthic invertebrates, with chlordane
and Gabrielsen, 1992). Due to the general sea-ice drift
and DDT having high concentrations in certain species.
pattern (Colony and Thorndike, 1985) and the possible
A number of Arctic benthic invertebrates have been
transport of contaminants by sea ice (Pfirman et al.,
analyzed for OCs since the previous AMAP assessment
1995), the contaminant occurrence in organisms in melt-
(see Annex Table 10). As with other invertebrates, PCB
ing areas, such as the marginal ice zone north of Sval-
concentrations were highest in benthic species, but the
bard and in the Fram Strait, is of special interest and
concentrations of the other OC groups varied with the
may explain elevated OC concentrations in Svalbard
invertebrates' feeding strategy (Figure 4 ·38). Scavenging
marine mammals and seabirds. Three species of amphi-
invertebrates, such as the amphipod Anonyx nugax and
pods, representing a number of feeding strategies, were
basketstar Gorgonocephalus arcticus, have HCH, CHL
analyzed for OCs (Borgå et al., 2002a; 2002b) including
and DDT concentrations that are within 30-50% of
Apherusa glacialis, Onisimus sp. and Gammarus wil-
PCB concentrations. In filter-feeding and detritus-feed-
kitzkii. OC concentrations increased from the more
ing invertebrates, such as Yoldia thraciaeformis or Cte-
herbivorous A. glacialis to the more carnivorous G.
nodiscus crispatus, the concentrations of other OC groups
wilkitzkii and the more necrophagous Onisimus sp.
are much lower (approximately 20%) than PCB con-
(Borgå et al., 2002a). The composition of compound
centrations. The highest concentrations of OCs in inver-
classes of HCHs, chlordanes, and DDTs was similar be-
tebrates are found in A. nugax, which have concentra-
tween the amphipod families, whereas the profiles of
tions in the same range as found in Arctic cod and the
PCBs differed.
little auk (seabird) (Fisk et al., 2001c). OC concentra-
Even though marine invertebrates have direct uptake
tions in filter- and detritus-feeding invertebrates are
by passive diffusion of contaminants across their gills,
among the lowest found in any biota in the world and
these results imply that the species' ecology, such as diet,
are similar to pelagic zooplankton (Figure 4 ·38).
is important in the bioaccumulation process of OCs. In
The blue mussel is a monitoring species that has been
addition, the results show that the sea-ice drift route in-
commonly used throughout the world, including the
fluences the concentrations of OC pollutants in sympa-
Arctic, to monitor OCs. PCBs and other OCs were pres-
gic organisms.
ent at very low levels in blue mussels from five locations
In sympagic amphipods, the levels and patterns of
in Nunavik, in the Ungava Bay and Hudson Strait areas,
OCs differed spatially, with higher -HCH concentra-
and two locations in Labrador, all from the eastern
tions in amphipods from the Fram Strait in comparison
Canadian Arctic (Fisk et al., 2002a) (see Annex Table 10
to amphipods collected north of Svalbard (Borgå et al.,
for locations). PCBs were present at much higher con-
2002c). This could be related to the sea-ice drift route,
centrations (range of means 3.7-46 ng/g ww) in mussel
since sea ice in the Fram Strait had a drift route across
tissues compared to other OCs. HCH isomers were the
the central Arctic Ocean, while the sea ice north of Sval-
next most prominent contaminants, with means ranging
bard had a western drift route to the sampling stations.
from 1.1 to 2.9 ng/g ww. The greater sorption of PCBs
The largest and longest-living sympagic amphipod,
to sediment particles filtered by mussels, compared to
G. wilkitzkii, lives up to five years, reaching a maximum
most other OCs, especially HCH, may account for the
body length of 62 mm (Lønne and Gulliksen, 1991;
much higher concentrations of PCBs. Doidge et al.
Poltermann, 1997; 2000). With increasing age and size,
(1993) found low ng/g ww levels of PCBs and OC pesti-
G. wilkitzkii switches gradually from herbivory to a more
cides in a survey of blue mussels from six communities
carnivorous diet (Werner, 1997; Poltermann, 2000; Scott
in Nunavik. Levels of PCBs in mussel samples from Ku-
et al., 2001). The OC burden in G. wilkitzkii may in-
ujjuaq were considerably higher than in the same species
crease with age due to bioaccumulation over time, and
at most other locations, suggesting that local contamina-
due to increased biomagnification associated with the
tion sources might be a factor.
amphipod's age and size-related shift in trophic position.
Levels of PCBs were determined in mussels (Mytilus
In addition, the contaminant burden in gilled organisms
trossulus) from 39 sites within the Aleutian Islands and
may be related to increasing size and body mass due to
five sites from southeast Alaska in 1994/1995 to deter-
changes in lipid content, total metabolism, and the sur-
mine whether high PCB levels in sea otter (Enhydra
face-to-volume ratio of gills which influences the ex-
lutris) were due to local sources (Reese, 1998). Very high
change rate of OCs with water (Landrum, 1988; Walker
PCB concentrations were found at Amchitka, Adak, and
et al., 1996). The OC concentrations in two size-classes
Unalaska Islands (83, 430, and 2800 ng/g dw, respec-
(small < 29 mm and large >29 mm) of G. wilkitzkii were
tively) but low levels were found elsewhere (ranging from
analyzed. The concentrations of more lipophilic com-
7.1 to 51 ng/g dw). This is a clear example of the influ-
pounds (e.g., PCBs) were lower in the smaller size-class,
ence of point source contamination, probably from mili-
whereas concentrations of more hydrophobic com-
tary facilities, in the Arctic, which results in concentra-
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
91
tions that rank with the most contaminated sites in
area of Reykjavík. At sites in southwestern, western,
North America. Spatial patterns of OC pesticides sug-
and northwestern Iceland, the levels were usually low
gest that these compounds come from sources that are
(14.7 ng/g ww ± 13.2 (SD)) (Skarphéinsdóttir et al.,
more distant.
1996). High levels of TBT are still found in the blue
In 1997, soft parts of blue mussels collected in the
mussel near larger harbors. Near Reykjavík harbor, the
Faroe Islands were analyzed for OCs (Larsen and Dam,
level of TBT was around 4420 ng/g dw in 2000 (Hall-
1999). The highest concentrations detected were for
dórsson, 2002).
CB153 and p,p'-DDE, both at 0.7 ng/g ww and CB138
TBT levels were examined in the dogwhelk along the
and p,p'-DDT, both at 0.4 ng/g ww. These concentra-
Norwegian coast from 1993 to 1995 (Følsvik et al.,
tions are in the range of those measured in blue mussels
1999) and again in 2000 (Green et al., 2002). The con-
in the eastern Canadian Arctic (Fisk et al., 2002a) but
centrations ranged from 8 to 141 ng Sn/g dw at sites
are much lower than those measured close to the mili-
within the AMAP area in 1993 to 1995. Out of ten sites
tary sites in southeastern Alaska.
north of 65° N, TBT was at or below the detection lim-
To assess the influence of point sources of pollutants
its at three of the sites. The most recent studies of TBT
on Svalbard (Spitsbergen), five species of benthic inver-
levels show that at eight locations in northern Norway,
tebrates were collected at various distances from possi-
the levels are lower than found in the earlier study
ble point sources in 1998 and 1999 and analyzed for
(Green et al., 2002). Two sites had less than 7 ng Sn/g
HCB, PAHs and PCBs (Hop et al., 2001). Stable isotope
dw, while at the rest of the sites, the levels ranged from
analysis revealed that these species were all feeding at
approximately 35 to 100 ng Sn/g dw.
a low trophic level. Local inputs of PAHs and PCBs
TBT levels were examined in the limpet, Patella vul-
seemed to be present in some of the island's harbors and
gata, at eight sites in the Faroe Islands (Følsvik et al.,
were elevated in benthic fauna compared to samples
1998). At only one site, near Tórshavn, were the levels
from Bjørnøya, which has little industry. The PCB pro-
above detection limits (90 ng Sn/g dw). Skarphéinsdót-
files were similar to technical PCB, suggesting a local
tir et al. (1996) measured TBT levels in the blue mussel
source. Concentrations were higher at sites closer to set-
and the dogwhelk at a single site near Reykjavík harbor
tlements. HCB did not appear to have local sources.
at different times of the year. The levels of TBT in the tis-
This study provides more evidence that point sources in
sue of the blue mussel and the dogwhelk seem to vary
the Arctic can have a significant influence on the ob-
considerably over the year at northern latitudes. High
served OC levels in wildlife.
levels (approximately 60 -70 ng/g ww) were found in the
In a recent study (Evenset et al., 2002), spider crabs
blue mussel from July to January, while from February
(Hyas araneus) were collected by diving in the littoral
to April, the levels were less than 15 ng/g ww. In the
zone off the southwest part of Bjørnøya (late June
dogwhelk, the summer and autumn levels were approxi-
2000). Spider crabs had slightly higher PCB and pesti-
mately 30 - 40 ng/g ww, while during late winter and
cide concentrations than zooplankton collected from the
early spring the levels were comparable to those found
same region. This study produced the first toxaphene re-
in the blue mussel. Skarphéinsdóttir et al. (1996) con-
sults for Arctic benthic invertebrates and showed that
cluded that monitoring of TBT in these animals at high
toxaphene is present, although at lower concentrations
latitudes should be confined to late summer or early
than PCBs, DDTs and HCHs.
autumn.
4.4.3.1. TBT
4.4.4. Marine and anadromous fish
TBT received limited attention in the first AMAP POPs
Marine and anadromous fish occupy a range of trophic
assessment, as only a few invertebrates had been ana-
positions in Arctic marine ecosystems, and hence con-
lyzed for TBT and its metabolites (DBT, MBT). TBT and
centrations of OCs are quite variable. The Arctic cod
its degradation products have now been measured in the
(polar cod, Boreogadus saida) is considered a key link in
blue mussel in Greenland, the Faroe Islands, Norway,
marine food webs between invertebrates and seabirds/
and Iceland. Most of the studies dealing with TBT in the
marine mammals, including the ringed seal and beluga.
western part of the Atlantic are from animals living
A number of these fish species are important compo-
south of the AMAP area (Chau et al., 1997; St-Jean
nents of the traditional human diet (e.g., Arctic char)
et al., 1999). In Greenland, TBT levels have only been
and several have become important commercially (e.g.,
examined near Nuuk, the largest town (13 000 inhabi-
Greenland halibut (turbot, Reinhardtius hippoglossoi-
tants) in central western Greenland (Jacobsen and As-
des)). There was a somewhat large dataset available for
mund, 2000). Levels there were quite low (close to
OCs in marine fish in the first AMAP POPs assessment
1 ng/g ww) despite the fact that Nuuk harbor hosts sev-
(de March et al., 1998). Less data have been produced
eral large shrimp trawlers. In the Faroe Islands, TBT
on these organisms since that report; however, the data
was measured in the blue mussel at eight sites in 1996.
produced recently are of improved quality with a greater
The levels ranged from 49 to 372 ng Sn/g dw (Følsvik et
range of contaminants measured, particularly PCB con-
al., 1998). Highest levels were found near Tórshavn, the
geners. Six marine fish species were recommended for
capital of the Faroe Islands. In northern Norway, the
inclusion in the AMAP Phase II monitoring program, in-
levels of TBT were generally very high in 1993 and 1994
cluding Arctic char, whitefish/cisco (Coregonus spp.),
(Berge et al., 1997), in particular near harbors, where
Arctic cod, Atlantic cod, sculpin (Myoxocephalus spp.)
levels as high as 4407 ng/g dw have been reported.
and long rough dab (Hippoglossoides platessoides).
In Iceland, the levels of TBT in the blue mussel were on
Data on `new' POPs have only been produced for a few
average 122.6 ng/g ww ± 92.5 (SD) near the large harbor
of these species.
92
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
OCs have generally been measured in the liver or
Concentration in Arctic cod, ng/g lw
muscle tissue of fish. The amount of lipid found in these
500
tissues can vary significantly within and between species
and needs to be taken into account when comparing lev-
els of OCs between species. For example, the Atlantic
Barrow
and Arctic cod have high-lipid livers and low-lipid mus-
cle, whereas the Greenland halibut has similar lipid con-
400
Baffin Bay
tent in liver and muscle. Differences in size, growth rate
PCBs
Barents Sea
Jan Mayen
(Johnston et al., 2002), and trophic position (Fisk et al.,
2001c) can all influence observed OC levels in fish and
need to be considered when comparing different popula-
300
tions, locations or studies. For most of the OC data pro-
duced for Arctic fish, these variables have not been ade-
quately accounted for.
Concentrations of OCs in marine fish are generally
higher than those observed in freshwater fish and ma-
200
rine zooplankton. For some larger species of fish, OC
levels are similar to ringed seals, likely due to feeding at
a higher trophic level (Fisk et al., 2002b).
DDTs
Sea-run Arctic char
100
Low levels of OCs were detected in anadromous Arctic
HCHs
char muscle (including skin) from two locations in
Labrador and three locations in Nunavik in the Cana-
dian Arctic (Muir et al., 2000c) (Annex Table 10). PCBs
0
were the most prominent contaminants at Labrador
Barrow
Northern
Jan Mayen
Barents Sea
Baffin Bay
sites, with concentrations averaging 30 ng/g ww in sam-
ples from Makkovik and 63 ng/g ww in samples from
Figure 4·39. Concentrations (±SD) of HCHs, DDTs, and PCBs
in Arctic cod collected in Barrow, Alaska (Hoekstra, 2002b), north-
Nain. PCB levels in char muscle samples from the three
ern Baffin Bay (Fisk et al., 2001c), Jan Mayen (Gabrielsen et al.,
locations in Nunavik were lower, with means ranging
1997), and that Barents Sea (Borgå et al., 2001).
from 13 to 18 ng/g ww. Statistical analysis showed that
there were no significant differences in PCB concentra-
centrations also seen in seawater. These spatial trends
tions among locations. Lipid content, length, and age
generally follow those of zooplankton (Section 4.4.3)
were not significant co-variates. PCB levels were, how-
but are not consistent with spatial trends observed in
ever, influenced by the sex of the fish, with males having
marine mammals and seabirds at higher trophic levels
significantly higher levels than females. This may be due
(Muir et al., 2000b) (Sections 4.4.5 and 4.4.6).
to the timing of sampling near the spawning period for
the char. Females may have mobilized fat from muscle to
Atlantic cod
reproduce and, subsequently, transferred contaminants
OC data were also generated recently (1998-2000) for
to their eggs as the fat is mobilized, thus lowering the
Atlantic cod from the Barents Sea (Borgå et al., 2001),
concentrations observed in muscle. The next most pro-
locations around Iceland (Yngvadóttir and Halldórsdót-
minent groups of OCs in char muscle were the HCH and
tir, 2002), and southwestern Greenland (Muir and Jo-
DDT groups, which were present at low ng/g levels.
hansen, 2001). Concentrations of OCs were consistent
DDT levels were higher at Nain and Lavrentiya than
at all locations. Concentrations (ng/g lw) of HCHs
other locations. In general, these levels of persistent OCs
ranged from 15 (Iceland) to 41 ng/g lw (Barents Sea) and
are similar to or lower than those reported in char mus-
PCB concentrations from 199 (Iceland) to 281 (south-
cle from other locations in the Canadian Arctic (Muir et
western Greenland) ng/g lw. In the Barents Sea, concen-
al., 1999b). Concentrations of all OCs were much lower
trations in Atlantic cod were about twice as high as
in muscle samples from sea-run char from Finland.
those observed in Arctic cod, and could be due to feed-
ing at a higher trophic level, larger size or longer life
Arctic (polar) cod
span of the Atlantic cod. The Icelandic data were part of
PCBs was the dominant OC group, followed by CHLs
a continuing monitoring program in Iceland, which also
in Arctic cod collected in northern Baffin Bay in 1998
includes the dab (Limanda limanda), and is discussed
(Fisk et al., 2002c), Barrow, Alaska in 1998 and 1999
under temporal trends in Section 5.4.2.
(Hoekstra et al., 2003a), and the Barents Sea in 1995
(Borgå et al., 2001). For Arctic cod collected around Jan
Faroe Islands fish
Mayen, DDTs was the next dominant OC group after
In the Faroe Islands, livers from shorthorn sculpin sam-
PCBs (Gabrielsen et al., 1997). Concentrations (lipid cor-
pled in 1999 and 2000 (n = 13 and 15) were analyzed
rected) of PCBs were quite similar in cod from the Bar-
(Hoydal et al., 2001). The single OC occurring in high-
ents Sea and around Jan Mayen but were somewhat
est mean concentrations was p,p'-DDE at 84 and 134
higher in northern Baffin Bay and Alaskan cod (Figure
ng/g ww in 1999 and 2000, respectively. The second high-
4 ·39). DDTs was somewhat higher in the northern
est mean concentration was CB153 at 58 and 94 ng/g
Baffin Bay Arctic cod than other locations. HCHs was
ww in 1999 and 2000, respectively. The concentrations
highest in the Canadian cod, reflecting the higher con-
of chlordanes, toxaphene, and mirex were less by a fac-
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
93
had higher levels. The Greenland halibut is a large, ben-
thic fish, which may account for the higher levels. OC
levels in the Greenland shark are discussed below in this
Concentration, ng/g lw
section. PCBs were the predominant OCs followed by
100
HCHs
Cumberland
Baffin Bay
DDTs and chlordanes in these fish, reflecting their gener-
Sound
Davis Strait
80
ally higher trophic level, as compared with zooplankton.
60
Greenland shark and Greenland halibut
Concentrations of OCs in the Greenland sharks col-
40
lected in the Davis Strait and Cumberland Sound region
20
in 1997 and 1999 (Fisk et al., 2002b) were in the range
of other top Arctic marine predators, the polar bear, and
0
glaucous gull (Figure 4 · 41). The Greenland shark is the
5000
only known shark to routinely inhabit Arctic waters,
PCBs
4000
and limited evidence indicates that these animals may be
long-lived (>100 years) (see Hansen, 1963) and poten-
3000
tially numerous. Concentrations (lipid basis) of OCs in
Greenland sharks in the study of Fisk et al. (2002b) were
2000
not related to fork length, sex, 13C or 15N. Greenland
1000
sharks had higher OC concentrations than black dogfish
(Centroscyllium fabricii), a small (< 1 m in length), deep-
0
water shark collected in Davis Strait (see Berg et al.,
1997). Lower OC concentrations in the black dogfish
Redfish Capelin
Arctic cod
Starry ray
were not unexpected because this species feeds lower in
Atlantic cod
the food web, mainly on crustaceans and small fish
Spotted wolffish
Shorthorn sculpinGreenland halibut
Greenland shark
(Compagno, 1984). Concentrations of OCs (lipid basis)
Figure 4· 40. Concentrations of HCHs and PCBs in Arctic ma-
in Greenland sharks were 10 -100 and 3 -10 times higher
rine fish collected in Davis Strait and Baffin Bay (all species except
than those observed in Greenland halibut and ringed
Greenland shark, which were collected in Cumberland Sound). Arc-
seals, respectively, suggesting a very high trophic posi-
tic cod data from (Fisk et al., 2001c), Greenland shark data from
tion. Marine mammals have been found in the stomachs
Fisk et al. (2002b), all other data from Denmark (2002).
of Greenland sharks (Fisk et al., 2002b). Concentrations
tor of 8 or more. There was large variability in OC con-
of DDTs in the study samples of Greenland sharks are
centrations between individual fish. No significant cor-
among the highest in Canadian Arctic biota, which may
relations between length or age and OC concentrations
be related to the low metabolism and long life span of
were found. Overall, the concentrations of OCs were
these sharks. Reported concentrations of PCBs and
higher in the year 2000 samples than in 1999. The rea-
DDTs in Greenland halibut collected in the Davis Strait
son may be related to the fact that the sampling stations
in 1992 (Berg et al., 1997) were five and ten times higher,
were not in identical locations between years. A local
respectively, but concentrations of CHL and HCH
pollution source at one of these sites as an explanation
were very similar to those reported for Greenland hal-
for between-year differences is not likely, due to the sim-
ibut in the study of Fisk et al. (2002b). The higher PCB
ilar ratios of concentrations for PCB, toxaphene, DDTs,
and DDT in Greenland halibut reported in Berg et al.,
and mirex.
(1997) could be due to the larger size and the deeper-
Results are also available for Atlantic cod sampled in
water habits of these Greenland halibut.
1997 at the Faroe Islands shelf (Larsen and Dam, 1999).
CB153 concentration, ng/g lw
Liver samples from 45 fish were analyzed in two pools
2500
with lipid contents of 56.9 and 53.5%. As for sculpin,
the single OC occurring in highest concentrations was
p,p'-DDE, at 40 and 37 ng/g ww, with CB153 having
2000
the second highest concentration at 25 and 26 ng/g ww,
respectively. In contrast to sculpin, the concentration of
1500
trans-nonachlor was similar to that of CB153, near 20
ng/g ww and p,p'-DDD was almost half the concentra-
tion of p,p'-DDE in Atlantic cod. In sculpin, the ratio of
1000
p,p'-DDD to p,p'-DDE was close to1/100.
500
Greenland marine fish
Concentrations of OCs have been measured in a range
0
of marine fish around Greenland (Figure 4· 40 and An-
Greenland
Beluga
Ringed
Greenland Glaucous
Polar
nex Table 10). A majority of these were collected as part
halibut
seal
shark
gull
bear
1999
1993
1993
1999
1998
1988
of a larger study on OCs in foodstuffs. There is a lack of
data from other Arctic regions to use for spatial compar-
Figure 4· 41. Mean (± SE) concentrations of CB153 in Greenland
halibut (Fisk et al., 2002b), beluga (Muir et al., 1999b), ringed seal
isons. Concentrations of OCs were fairly consistent
(Muir et al., 1999c), Greenland shark (Fisk et al., 2002b), glaucous
across species with the exception of the Greenland shark
gull (collected in northern Baffin Bay, Fisk et al., 2001c), and polar
(Somniosus microcephalus) and Greenland halibut, which
bear (mean only) (Norstrom et al., 1998) from Cumberland Sound.
94
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Jan Mayen fish
effects related to POP exposure have been seen in highly
Long rough dab, capelin (Mallotus villosus), grey gur-
contaminated glaucous gulls (Bustnes et al., 2000), and
nard (Eutrigla gurnardus), coalfish (Pollachius virens), At-
concerns about POP effects remain for some other
lantic poacher (Leptagonus decagonus), daubed shanny
species of Arctic seabirds. Seabirds also have the poten-
(Lumpenus maculates), and checkered eelpout (Lycodes
tial to biologically transport POPs from one region to
vahli) were collected from around Jan Mayen, and liver
another (e.g., marine to the freshwater ecosystems)
samples were analyzed for OCs (Gabrielsen et al., 1997).
through the production and release of guano (see Sec-
PCBs were the predominant contaminants followed by
tion 4.3.5).
DDTs. On a lipid weight basis, the highest OC concen-
There has been a considerable amount of work done
trations were seen in long rough dab and checkered
on POPs in Arctic seabirds since the first AMAP assess-
eelpout.
ment report, encompassing a wide range of species (An-
nex Table 11). Continued monitoring of POPs in Cana-
Toxaphene in fish from European waters
dian Arctic seabird eggs from 1975 to 1998 and beyond,
Concentrations of three toxaphene congeners (Parlars
has provided a strong dataset for examining temporal
26, 50 and 62) were determined in 221 fish samples,
trends between different species (Section 5.4.3). A com-
covering 23 species from northern European waters
prehensive study of OCs in Barents Sea seabird eggs
(McHugh et al., 2000). Levels of the three congeners
(Barrett et al., 1996) was not included in the first AMAP
were highest in the Barents Sea and Norwegian Sea re-
POPs assessment. A number of studies have also been
gions compared with the coast of Iceland, the North Sea,
carried out examining OC concentrations and dynamics
and the Baltic Sea. However, some of the differences be-
in adult seabirds (Henriksen et al., 2000; Borgå et al.,
tween regions could be due to the use of different fish
2001; Fisk et al., 2001b), some of which were part of
species, which will feed differently and influence expo-
larger studies examining spatial trends (Gabrielsen et al.,
sure levels. Toxaphene concentrations in these fish are in
1997) or food web dynamics of OCs, discussed in Sec-
the range reported for other marine fish from this region
tion 4.4.9. New data on PCDD/Fs, toxaphene, and `new'
(see Annex Table 10).
POPs have also been generated for Canadian seabirds
(Braune et al., 2001a) and on mono-ortho and non-
ortho PCBs, toxaphene, and `new' POPs in glaucous
4.4.4.1. `New' chemicals in marine and anadromous fish
gulls on Bjørnøya and Svalbard (Daelemans et al., 1992;
PBDEs in marine fish
Burkow et al., 2001; Herzke et al., 2003).
PBDEs have been determined in the liver of a few species
PCBs are the most common OCs measured in Arctic
of marine fish: Atlantic cod and tusk (Brosme brosme)
seabirds (see Figure 4 · 42) (Barrett et al., 1996; Borgå et
from Norway (Herzke, 2002a); and, Atlantic cod (liver
al., 2001; Braune et al., 2001b; Buckman et al., 2004),
and muscle) and Greenland halibut (liver) from Green-
although the relative amounts are related to the trophic
land (Muir and Johansen, 2001) (Annex Table 17).
position of the seabird (Borgå et al., 2001). Higher
PBDE levels in the liver of the Norwegian fish ranged
trophic-level seabirds generally have a larger proportion
from 24 to 109 and 60 to 300 ng/g lw in the Atlantic cod
of PCBs as a percentage of total OCs. This is due to the
and tusk, respectively. These concentrations are much
greater biomagnification potential of PCBs and the abil-
higher than levels observed in the fish off southwestern
ity of seabirds to metabolize other OCs, such as -HCH
Greenland. Shorthorn sculpin, cod, spotted wolffish,
(Moisey et al., 2001) and some chlordane components
and starry ray were studied during 2000 near the west-
(Fisk et al., 2001b). Other recalcitrant and biomagnify-
ern Greenland villages of Quaqortoq (3500 inhabitants),
ing OCs, such as p,p'-DDE and oxychlordane, also be-
Igaliko (30 inhabitants), and Usuk (background site 3-5
come more prevalent (Borgå et al., 2001, Fisk et al.,
km from Igaliko) (Christensen et al., 2002; Vorkamp et
2001b), although the relative proportions can vary dra-
al., 2002). The highest concentrations of PBDEs were
matically between species, even within the same family
observed in fish from Quaqortoq (46 ng/g lw) followed
(Fisk et al., 2001b). Of particular note are the relative
by Igaliko (18 ng/g lw) and Usuk (12 ng/g lw). The levels
proportions of HCH isomers, which in seabirds are
of PBDEs were 15-24 times lower than PCB levels meas-
dominated by -HCH (Barrett et al., 1996; Moisey et
ured in the same individuals, except for shorthorn scul-
al., 2001). Seabirds are able to efficiently metabolize -
pin collected at Quaqortoq, where the level of PCBs
and -HCH but not -HCH (Moisey et al., 2001).
was 40 times higher. For all fish, BDE47 dominated the
PBDE congener pattern.
Species comparison
OC concentrations in seabirds were, in general, related
to trophic position and secondarily to migration, with
4.4.5. Seabirds
the highest concentrations found in great skuas, great
There are approximately fifty species of Arctic seabirds
black-backed gulls, and glaucous gulls. These are species
(de March et al., 1998). They have a variety of feeding
that scavenge, prey on other seabird species, and migrate
and migration strategies, and accordingly, POP concen-
to more southerly habitats in the winter (Barrett et al.,
trations can vary considerably among species. Species,
1996; Gabrielsen et al., 1997; Borgå et al., 2001; Fisk et
such as the glaucous gull, great skua (Stercorarius skua),
al., 2001c). Glaucous gulls, however, do not migrate as
and great black-backed gull (Larus marinus), that may
far as the other two species. These concentrationtrophic
migrate to more contaminated regions and/or that scav-
level relationships in seabirds hold throughout the Arc-
enge, particularly on dead marine mammals, have the
tic, including the Barents Sea area, and around the Jan
highest POP concentrations (Gabrielsen et al., 1997;
Mayen, northern Baffin Bay, and the Iceland regions
Borgå et al., 2001; Fisk et al., 2001b; 2001c). Biological
(Barrett et al., 1996; Gabrielsen et al., 1997; Borgå et al.,
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
95
Concentration in liver, ng/g, lw
Concentration in liver, ng/g, lw
1000
700
A
A
A
A
A
A
A
B
B
B
B
C
C
C
600
D
D
D
D
800
CBz
HCHs
500
600
400
300
400
200
200
100
0
0
10 000
A
A
A
A
A
A
B
B
B
B
B
4000
C
C
C
8000
CHLs
DDTs
3000
6000
2000
4000
1000
2000
0
0 Dovekie Thick- Black Black- Ivory Glau- Northern
billed
guille-
legged
gull
cous
fulmar
murre
mot
kittiwake
gull
12 000
A
A
A
A
B
B
C
C
D
D
10 000
PCBs
8000
6000
4000
Figure 4· 42. Mean (± SE) concentrations of CBz, HCHs, CHLs,
DDTs, and PCBs in liver tissue of Northwater Polynya seabirds
(Buckman et al., 2003). Concentrations in males and females did
2000
not significantly differ (p < 0.05) except for DDTs, and data were
therefore combined. Bars with the same letter do not differ signifi-
0
cantly (p > 0.05).
Dovekie Thick-
Black
Black-
Ivory
Glau- Northern
billed
guille-
legged
gull
cous
fulmar
murre
mot
kittiwake
gull
2001; Fisk et al., 2001c; Ólafsdóttir et al., 2001). In
Black-legged kittiwakes have been shown to feed at a
northern Baffin Bay, ivory gull (Pagophila eburnean) and
lower or similar trophic level as the black guillemot (Hob-
northern fulmar (Fulmarus glacialis), both of which scav-
son et al., 2002). Kittiwakes are known to migrate longer
enge, had slightly lower OC concentrations than glau-
distances (e.g., to southern regions) than black guille-
cous gulls from the same area but higher concentrations
mot, which probably only move locally during the win-
than other seabirds (Figure 4 · 42) (Buckman et al.,
ter (Anker-Nilssen et al., 2000). Therefore, the higher
2004). OC concentrations in black-legged kittiwakes
OC concentrations in black-legged kittiwakes are likely
(Rissa tridactyla), a non-scavenging species, were lower
to be a result of uptake at their winter habitat, highlight-
than scavenging seabird species but were higher than the
ing the impact, in both the Canadian and European Arc-
fish- and zooplankton-eating alcids (guillemots, murres,
tic, of migration to more contaminated regions.
and little auks) in both Baffin Bay and the Barents Sea
OC concentrations can also vary within a single pop-
area. On Jan Mayen, dovekies had the lowest OC con-
ulation of seabirds. Sagerup et al. (2002) observed a
centrations; black-legged kittiwakes, fulmars, and black
large range of OC concentrations in the livers of glau-
guillemots had intermediate concentrations; and, highest
cous gulls collected in the western Barents Sea in 1996.
concentrations were found in glaucous gulls, great black-
For example, PCB concentrations ranged from 16 000
backed gulls, and great skuas (Gabrielsen et al., 1997).
to 292 000 ng/g lw. Concentrations of OCs were signifi-
96
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
cantly correlated to 15N (r2 = 0.18), and therefore, diet
PCB concentration,
accounted for some of the variation within this popula-
ng/g lw
10 000
tion. Bustnes et al. (2000) studied two colonies of glau-
cous gulls on Bjørnøya that nested only a few kilometers
from each other but had different food habits. The two
colonies had different OC concentrations, with the cliff
Thick-billed
colony having much higher concentrations than the sea-
5000
murre
level colony. The colony that nested on cliffs fed more on
Black guillemot
other seabird eggs and chicks, whereas indications were
Black-legged
that the sea-level colony fed more on fish (i.e. fed at a
kittiwake
lower trophic level).
0
Influence of sex and tissue
Lipid-corrected concentrations of OCs have rarely been
found to vary significantly between sexes or tissues of
seabirds (Ólafsdóttir et al., 1998; Buckman et al., 2004).
For example, concentrations of OCs were found to be
similar between liver and muscle, tissues with similar
lipid content, of the common eider (Somateria mollis-
sima) collected in Iceland (Ólafsdóttir et al., 1998). This
is a commonly observed phenomenon and reflects the
hydrophobic nature of OCs and accumulation in lipid.
Lipid-normalized concentrations of OCs generally did
not vary to a large extent between liver and fat in sea-
birds (Buckman et al., 2004; Fisk et al., 2001b), but lipid-
corrected concentrations of chlordane compounds were
significantly lower in the liver compared with the fat of
Figure 4· 43. Concentrations of PCBs in liver (solid columns) and
little auks collected in Baffin Bay in May/June. At that
eggs (lighter-shaded, outlined columns) of thick-billed murre, black
time, little auks are feeding heavily on low trophic-level
4 4 5 2
guillemot, and black-legged kittiwakes from regions throughout the
zooplankton (e.g., copepods) in anticipation of repro-
Arctic. Data for the Bering Sea (year of collection: 2000; Vander Pol
duction and egg production. Ólafsdóttir et al. (1998)
et al., 2002), Prince Leopold Island (1998; Braune et al., 2001a),
observed large seasonal changes in OC concentrations in
northern Baffin Bay (1998; Buckman et al., 2002), West and East
Greenland (1999, 2000; Muir and Johansen, 2001), Barents Sea
the muscle and liver tissue of the common eider, which
(1995; Borgå et al., 2001 and; 1995; Gabrielsen et al., 1997),
were attributed to relocation of OCs to these tissues due
Bjørnøya (1999; Evenset et al., 2002), Faroe Islands (1995/96; Hoy-
to the shrinking of body fat. Therefore, changes in diet,
dal et al., 2001), and Jan Mayen (1995; Gabrielsen et al., 1997).
the effects of migration and/or reproduction can, in cer-
tain cases, result in differences between tissues and in
Canadian Arctic due to the closer proximity to Asia,
seasonal changes in OC concentrations in seabirds.
where HCH has recently been used. DDT concentra-
tions were similar within and between species in the Can-
Spatial trends
adian and Barents Sea thick-billed murres, black guille-
Spatial trends of OCs in Arctic seabirds varied with the
mots, and kittiwakes but were lower in the Greenland
seabird species and the chemical, and generally were in
seabirds. There was much more variation for PCB con-
agreement with spatial trends observed previously in
centrations (Figure 4 · 43). For black guillemots, highest
seabirds (de March et al., 1998) and marine mammals
PCB concentrations were found on Jan Mayen (15 300
(Muir and Norstrom, 2000; Muir et al., 2000b). Con-
ng/g lw in liver) followed by Iceland (4560 ng/g lw in
centrations of most OCs in seabirds are highest in the
muscle, not shown in figure). The higher concentrations
Russian part of the Barents Sea and lowest in the North
on Iceland could in part be due to the inclusion of birds
American Arctic, with the exception of HCH, which is
collected in 1991 and 1992 and/or due to muscle being
higher in the North American Arctic (Annex Table 11).
analyzed instead of liver. For thick-billed murres, highest
There is a lack of data for the eastern Russian Arctic.
PCB concentrations were seen in the Barents Sea area
PCB data for four seabird species (thick-billed mur-
and lowest concentrations in the North American Arc-
re or Brünnich's guillemot, black guillemot, black-legged
tic. Black-legged kittiwakes had the highest PCB con-
kittiwake, and glaucous gull) are available from a num-
centrations of the three non-scavenger species, with
ber of locations, and highlight the geographical trends
highest concentrations found in the eastern Barents Sea
despite different tissues having been analyzed. The first
around Novaya Zemlya and Franz Josef Land. PCB
three of these seabird species are non-scavengers, feeding
(10 000 - 21 000 ng/g lw) and DDT concentrations
on zooplankton and fish, although the black guillemot is
(500 -1900 ng/g lw) in the kittiwakes from around the
more of an inshore feeder. Black guillemots do not mi-
Barents Sea region, including Svalbard, Bjørnøya, Franz
grate, but thick-billed murres do. Black-legged kittiwakes
Josef Land, Novaya Zemlya, and the Kola Peninsula,
migrate long distances, exposing themselves to higher
were fairly similar and are probably indicative of expo-
levels of OCs in more southerly habitats. HCH concen-
sure due to migration more than to local sources.
trations were highest in the Canadian seabirds (no HCH
Concentrations of PCBs and DDTs in glaucous
data are available for the Bering Sea murres), which re-
gulls, a high trophic-level scavenging seabird, were higher
flects the higher concentrations of these chemicals in the
in the Barents Sea and Jan Mayen than in Baffin Bay,
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
97
Concentration in glaucous gull liver,
man et al., 2004). Lipid content in the eggs of the three
ng/g lw
species was similar, allowing comparisons of wet weight
100 000
concentration data. PCB was the predominant OC in all
75 000
three species and was similar in black-legged kittiwakes
and northern fulmars (280 ± 20 and 270 ± 20 ng/g ww,
50 000
respectively) and nearly twice that observed in thick-
25 000
billed murres (130 ±10 ng/g ww). This reflects the higher
0
trophic level of northern fulmars and black-legged kitti-
DDTs PCBs
wakes and migration to more contaminated habitats by
the kittiwakes. DDTs was highest in the northern ful-
mar (210 ± 20 ng/g ww), followed by the thick-billed
murre (100 ±10 ng/g ww) and the black-legged kittiwake
(60 ±10 ng/g ww), and similar trends were observed for
CHLs.
Faroe Islands black guillemots
A large study of black guillemots in the Faroe Islands in
1995 and 1996 (Dam, 2000) revealed that the black
guillemot had distinctive winter and summer diets,
where fish (primarily Amodytidae or sandeel type) made
up a substantial dietary component in spring and early
summer along with Galathea spp. crustaceans. In winter,
the diet was dominated by Galathea spp. and gas-
tropods, in particular the banded chink shell, Lacuna di-
Figure 4· 44. Concentrations of PCBs and DDTs in glaucous gull
vericata. Indications of elevated OC concentrations in
liver. Data for Baffin Bay are from Fisk et al. (2001b), for all other
sites data are from Gabrielsen et al. (1997).
liver of adult males and females in spring hints to a pos-
sible link to a fish-dominated diet at that time. The sin-
with highest concentrations around Franz Josef Land
gle OC occurring in highest concentrations was most
(Figure 4 · 44). Higher PCB and DDT concentrations
often CB153, but the concentration differences between
in seabirds from the Barents Sea region, relative to
this PCB congener and p,p'-DDE were small, and in
seabirds from more westerly regions, have been ob-
some samples, nonexistent. In April 1996, the CB153
served previously (de March et al., 1998). OC levels, in-
concentrations in adult females and males were 37 and
cluding PCBs and DDTs in zooplankton and fish
42 ng/g ww and p,p'-DDE concentrations were 24 and
from the Barents Sea were within the range of those
30 ng/g ww, respectively. In August 1996, the respective
recorded in similar species in the Canadian Arctic. The
CB153 concentrations were 20 ng/g ww and 24 ng/g
low OC levels in selected taxa at lower trophic positions
ww, and p,p'-DDE concentrations were 9 ng/g ww and
were unexpected, based on the higher levels of PCB
10 ng/g ww in females and males, respectively.
and DDT, in particular, in higher trophic-level preda-
tors in the Barents Sea compared to the Canadian Arctic
Grey heron and shag from Norway
(Borgå et al., 2001). Therefore, a diet of pelagic organ-
PCB concentrations (34 congeners) were measured in
isms does not seem to explain the elevated concentra-
the yolk sac of grey heron (Ardea cinerea) hatchlings
tions in top predators in the Barents Sea area, here ex-
from two populations in Norway, at Frøya (mid-Nor-
emplified by glaucous gulls. A diet of ice-associated
way) and Finnfjordøy (northern Norway) (Jenssen et al.,
fauna may, however, be of importance in the bioaccumu-
2001). No statistically significant differences were seen
lation of OCs (Norstrom et al., 1998). As suggested by
in PCB concentrations between the two populations.
Pfirman et al. (1995), contaminated particles in the sea
Mean PCB concentrations were 2070 (Frøya) and 2450
ice may be released in the melting areas in the Fram
ng/g ww (Finnfjordøy) with ranges of 570-4520 ng/g
Strait and the Barents Sea, followed by bioaccumulation
ww and 1360-4910 ng/g ww, respectively. Similarly,
in ice-associated fauna. However, ice-associated fauna
yolk sacs from newly hatched shag chicks (Phalacroco-
from the marginal ice zone near Svalbard have low OC
rax aristotelis), from the island of Sklinna on the central
levels (Borgå et al., 2002b; 2002c), which correspond to
Norwegian coast were analyzed for 29 PCB congeners
levels in zooplankton at similar trophic positions from
(Murvoll et al., 1999). The mean PCB concentration
the Barents Sea (Borgå et al., 2001).
was 1200 ng/g ww.
Canadian seabird eggs
Alaskan bald eagle eggs
As part of a continuing temporal-trend study of contam-
Levels of OCs were measured in the eggs of bald eagles
inants in seabird eggs (see Section 5.4.3), thick-billed
(Haliaeetus leucocephalus) from four islands of the
murre, northern fulmar, and black-legged kittiwake eggs
Aleutian Archipelago to assess their possible role in low
were collected on Prince Leopold Island in Lancaster
reproductive productivity on one of the islands, Kiska
Sound in 1998 and analyzed for OCs (Braune et al.,
Island (Anthony et al., 1999). Bald eagles are resident on
2001b). Concentrations and the relative proportions of
these islands and do not migrate. Samples were collected
OC groups were in general agreement with those ob-
in 1993 and 1994, and OC pesticides were elevated in
served in tissues of adult birds of the same species col-
eggs from all four islands. No statistically significant dif-
lected in northern Baffin Bay (Fisk et al., 2001b; Buck-
ferences were seen between the four islands for -HCH,
98
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
dieldrin, HCB or heptachlor epoxide concentrations.
Yolk sacs from grey heron hatchlings from two sites
p,p'-DDE concentrations ranged from 300 to 4100 ng/g
in Norway (Frøya, Finnfjordøy) had TEQs based on
ww, but were significantly higher in the eggs collected on
mono-ortho PCBs of 79.4 pg/g ww and 93.2 pg/g ww,
Kiska Island (geometric mean of 2750 ng/g ww) as com-
respectively (Jenssen et al., 2001). Ranges were 21-179
pared to Adak, Tanaga, and Amchitka Islands (geomet-
and 55-177 pg/g ww, respectively. Yolk sacs from shag
ric means of 750-950 ng/g ww). Trans-nonachlor, mirex,
hatchlings from Sklinna (central Norwegian coast) had
oxychlordane, and mercury concentrations followed the
TEQs based on mono-ortho PCBs of 44 pg/g ww (Mur-
same general pattern as DDE, with highest concentra-
voll et al., 1999).
tions on Kiska Island. Kiska Island is furthest west, and
Liver samples from glaucous gulls from Longyear-
the authors concluded that the eastwest increase in
byen on Svalbard were analyzed for PCBs including
concentrations suggested Asiatic sources of these con-
non- and mono-ortho PCBs (Daelemans et al., 1992).
taminants. PCB concentrations (as Aroclor 1260) ranged
The TEQ concentration based on these congeners was
between 100 and 9900 ng/g ww on the four islands and
2500 pg/g ww. Toxaphene was measured in the liver of
were highest on the three islands (Adak, Kiska, and Am-
eighteen glaucous gulls collected from Bjørnøya and
chitka) that had military facilities (geometric means of
four from Longyearbyen in 1999 (Burkow et al., 2001;
2100, 2090, and 1700 ng/g ww, respectively). PCB con-
Herzke et al. 2003). Additionally, toxaphene was ana-
centrations on Tanaga Island were much lower (geomet-
lyzed in the intestinal contents of fifteen of the glaucous
ric mean of 700 µg/g ww). The Kiska Island bald eagles
gulls from Bjørnøya. Toxaphene Parlars 50 and 26 had
had a higher percentage of seabirds, such as northern
average concentrations of 10 and 19 ng/g ww, respec-
fulmars and glaucous-winged gulls, in their diet, which
tively, in liver and were the dominant toxaphene con-
could explain their higher OC concentrations. This
geners. For glaucous gulls from Bjørnøya, total toxa-
study highlights the potential for local OC contamina-
phene concentrations in gut contents were 84 ng/g ww,
tion from military activities to result in elevated OC con-
in posterior colon contents 53 ng/g ww, and in muscle
centrations in wildlife.
175 ng/g ww (Evenset et al., 2002). Levels of toxaphene
were up to 100 times lower than PCBs and some of the
PCDD/Fs, mono- and non-ortho PCBs,
legacy OC pesticides.
and toxaphene in seabirds
Recently, compounds such as PCDD/Fs, non-ortho PCBs
4.4.5.1. `New' chemicals in seabirds
and toxaphene were analyzed in thick-billed murres,
northern fulmars, and black-legged kittiwakes collected
A number of very recent studies have examined levels of
on Prince Leopold Island in Lancaster Sound (Braune et
`new' chemicals in Arctic seabirds, in particular bromi-
al., 2001a) (Annex Table 16). These compounds have not
nated compounds (Annex Table 17).
been measured previously in Canadian Arctic seabirds.
Samples included livers from 1975 and 1993 and egg
Canadian seabirds
samples from 1993. This study was set up as a pilot study
A range of `new' chemicals was measured as part of the
to determine if temporal changes had occurred, and is ex-
PCDD/F and toxaphene analyses in Arctic seabirds de-
amined in more detail in Section 5.4.3. PCDD/Fs and
scribed in Section 4.4.5 (Braune et al., 2000; 2001a).
non-ortho PCBs were found in all Arctic seabird samples
These include livers (1975 and 1993) and eggs (1993)
analyzed in this study. In particular, concentrations of
from thick-billed murres, northern fulmars, and black-
HxCDDs, PeCDFs and HxCDFs found in Arctic seabird
legged kittiwakes collected on Prince Leopold Island in
livers exceeded levels reported for marine mammals in
Lancaster Sound. These results are discussed in more de-
the Canadian Arctic (de March et al., 1998) by several
tail in the temporal-trends section (Section 5.4.3).
orders of magnitude. Ringed seals, polar bears, and wal-
PBDEs were present at low ng/g levels in most of the
rus (Odobenus rosmarus) in the Canadian Arctic tend to
samples analyzed. The highest estimated PBDE levels (3
have congener profiles dominated by higher TCDD and
ng/g ww or about 60-70 ng/g lw) were detected in the
lower PeCDD and PeCDF levels (de March et al., 1998),
1993 egg and liver samples of kittiwakes, and the 1993
whereas Arctic seabirds show the reverse profile. Con-
murre and fulmar samples also contained ng/g levels.
centrations of PCDD/F homologues in the Arctic seabirds
BDE47 was the major PBDE congener in all the samples.
are in the range reported for seabirds from temperate
Although the data suggest that exposure to PBDEs has
North America and Europe (Hebert et al., 1994; van den
increased from 1975 to 1993, the highest level reported
Berg et al., 1987). Toxaphene was detected in every
is an order of magnitude lower than levels reported for
seabird sample analyzed, except for the pool of kittiwake
Swedish common guillemots from the Baltic Sea in 1993
livers from 1975, and concentrations were one to two or-
(720 ng/g lw) (Sellström et al., 1993; 2003; Sellström,
ders of magnitude lower than reported for marine mam-
1999), but is still higher than levels reported for Cana-
mals from the Canadian Arctic (Muir et al., 1999b).
dian marine mammals (Stern and Addison, 1999; Stern
PCDD/F concentrations in common guillemot eggs
and Ikonomou, 2000; 2001). However, PBDE concen-
from the Faroe Islands sampled in 2000 were 10 pg/g ww
trations in Baltic Sea guillemots have declined since their
(Mikkelsen, 2002). These concentrations were lower
peak in the mid-1980s and were lower (143 ng/g lw) in
than seen in pilot whale blubber from the Faroe Islands,
1999 (Sellström et al., 2003). Temporal trends of PBDEs
indicating a similar relationship as seen in the Canadian
in marine mammals indicate increasing levels in the
Arctic between seabirds and mammals. However, the
Canadian Arctic during the period of decline in the
difference between the TEQs in pilot whale and guille-
Baltic Sea (see Section 5.4.6.1), implying that concentra-
mot were less pronounced, approximately six times
tions in Canadian Arctic seabirds may be approaching
higher on a lipid weight basis (Mikkelsen, 2002).
those of guillemot in the Baltic Sea.
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
99
Halogenated dimethyl bipyrroles (HDBPs), which
guillemots for the same year. Levels of PBDE were up to
are naturally-occurring, mixed bromine/chlorine persist-
100 times lower than levels of PCBs and some of the
ent organic compounds, have been shown to bioaccu-
legacy OC pesticides.
mulate in seabird eggs (Tittlemier et al., 1999). HDBPs
Butyltins have recently been measured in glaucous
were detected in all of the 1993 samples and only one
gulls from Bjørnøya (Table 4·8, page 111). Liver samples
of the liver samples from 1975. The major contami-
were found to contain the TBT metabolites, DBT (detec-
nant found was 1,1'-dimethyl-3,3',4,4'-tetrabromo-5,5'-
tion limit to 51 ng/g ww), and MBT (detection limit to
dichloro-2,2'-bipyrrole (DBP-Br4Cl2). The highest esti-
14 ng/g ww), but no TBT (Berge et al., 2002).
mated level (a total of 5 ng/g ww) was found in the kitti-
wake egg sample from 1993. Trace amounts (<2 ng/g
Greenland seabirds
ww) of chlorinated terphenyls, hexabrominated biphe-
PBDE levels were determined in the liver of thick-billed
nyls, and tris(4-chlorophenyl)methane (TCPMe) were
murre and black guillemot collected from southwestern
also detected in most of the Arctic seabird samples. No
Greenland in 1999 (Muir and Johansen, 2001). Concen-
chlorinated diphenyl ethers, TCPMe or PCNs were de-
trations of PBDE in the thick-billed murre (1.7±1.6
tected in any of these samples (detection limit approxi-
ng/g ww; 32 ng/g lw) and guillemot (3.0 ± 2.8 ng/g ww;
mately 2 ng/g ww).
46 ng/g lw) were similar to levels observed in Canadian
In a separate study, Tittlemier et al. (2001) examined
Arctic seabird eggs but lower than observed in glaucous
levels of HDBPs in four seabird species (dovekie, black
gulls from Bjørnøya.
guillemot, black-legged kittiwake, and glaucous gull)
collected in northern Baffin Bay. This is significant be-
Northern Norway
cause it represents the first time a naturally produced
New data on dioxin-like substances, PCNs, PBDEs, and
halogenated compound has been measured in Arctic
toxaphene in herring (Larus argentinus) and great black-
species. This was part of a larger study on the food web
backed gull eggs from northern Norway were recently
dynamics of these chemicals in marine food webs (Sec-
produced (Gabrielsen, 2002). Eggs were collected in 2001
tion 4.4.9). HDBPs were detected in all of the samples
from four sites: Alta, Kongsfjord (Finmark), Sommarøy,
studied from the Northwater Polynya. Levels of DBP-
and Vardø. Twenty eggs from each site were pooled into
Br4Cl2 in the seabirds were generally similar to those
one sample. Concentrations of PCNs, PBDEs, and tox-
recorded in seabird samples from Atlantic Canada (Titt-
aphene and total TEQs were similar between regions, al-
lemier et al., 1999). A comparison cannot be made for
though levels were somewhat lower in Alta (Annex Ta-
the other congeners measured since this study contains
bles 15, 16 and 17). TEQ values in these gull eggs are
the first reported concentration data for these congeners.
similar to levels measured in Arctic Canadian seabird eggs
Little auks provide the single clear exception where
(Braune, 2001). PBDE and toxaphene levels in these sea-
DBP-Br4Cl2 concentrations (1.76 ng/g ww) were ap-
birds are slightly higher than measured in Bjørnøya
proximately ten times lower than those of the Atlantic
glaucous gulls (Burkow et al., 2001; Herzke et al. 2003).
puffin (Fratercula artica) (20 ng/g ww), a species that
has a similar winter habitat but a more piscivorous diet.
Chiral pesticides
The difference in concentrations is likely driven by the
Chiral pollutants exist as two mirror-image forms or op-
little auks feeding at a lower trophic position just prior
tical isomers called enantiomers. Enantiomers have iden-
to their collection in early summer (Fisk et al., 2001b).
tical physical-chemical properties and abiotic degrada-
In the majority of the bird species, DBP-Br4Cl2 was the
tion rates, but can have different rates of biotransforma-
predominant congener. The exception occurred with
tion (Buser and Müller, 1992). The chemical manufac-
black guillemots, where DBP-Br6 was the most abun-
turing process results in a mixture containing approxi-
dant congener. This may be due to black guillemots feed-
mately fifty percent of each chiral compound, called a
ing on benthic organisms during part of the year (Gas-
racemic mixture. Selective biotransformation of one chi-
ton and Jones 1998).
ral component over another can occur and result in an
enantiomeric enrichment (Buser and Müller, 1992). This
Bjørnøya seabirds
selective enrichment originates from one enantiomer
Brominated flame retardants were measured in the liver
being more easily biotransformed. The resulting selec-
and intestinal contents of fifteen glaucous gulls collected
tive accumulation of a single enantiomer can provide in-
on Bjørnøya in 1999 (Burkow et al., 2001; Herzke et al.,
formation on fate and dynamics of the chemical and
2003). Only two PBDE congeners were detected, BDEs
may have significant toxicological ramifications. It has
47 and 99, at concentrations between 2 and 25 ng/g ww
been proposed that comparison of enantiomer ratios
(27-450 ng/g lw). Analysis of the samples using gas
(ERs) or enantiomer fractions (EFs) may provide infor-
chromatography/high resolution mass spectroscopy re-
mation on biotransformation capacity of species and the
vealed a number of other PBDE and polybrominated
trophic transfer of contaminants in a food web (Wiberg
biphenyl (PBB) congeners. BDE47 dominates the PBDE
et al., 2000).
congener pattern in seabirds. PBDE levels in most
Enantiomeric fractions of chiral chlordane compo-
species are approximately 20 times lower than PCB
nents were examined in the liver and fat of seven Arctic
levels, but are up to 1000 times lower for glaucous gulls.
seabird species collected in northern Baffin Bay in 1998
For most glaucous gulls, these concentrations are similar
(Fisk et al., 2001b). EFs of chiral components failed to
to what has been measured in seabird eggs from the
predict concentration or trophic level, but did identify
Canadian Arctic (Braune, 2000). However, a few indi-
biotransformation differences between species and chlor-
vidual glaucous gulls had higher PBDE levels (480-560
dane components. The relative proportions of chlordane
ng/g lw), which were higher than levels seen in Baltic Sea
components in seabirds were related to taxonomy and
100
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
the magnitude of EF values; the northern fulmar and gulls
benzenes, toxaphene components, dieldrin, mirex, and
(black-legged kittiwake, ivory gull, and glaucous gull)
PBDEs are not well represented in overall contaminant
had a greater percentage and higher EFs for oxychlor-
measurements in marine mammals across the Arctic.
dane than the alcids (little auk and black guillemot). The
PCDD/Fs have also only been quantified to a limited ex-
exception was the thick-billed murre, an alcid, where
tent across marine mammal species or geographical lo-
oxychlordane made up a significant percentage of its
cations in the Arctic (Annex Table 16).
CHLs. Thick-billed murres appeared to have a greater
capacity to metabolize and eliminate chlordane, based
4.4.6.1. Pinnipeds
on high proportions of oxychlordane and the highest
EFs for oxychlordane and heptachlor epoxide.
Ringed seals
Ringed seals are the most abundant and widely distrib-
uted resident Arctic pinniped. Their diet consists of fish,
4.4.6. Marine mammals
mainly schooling gadids, and crustaceans (amphipods,
There is an extensive database on OCs in Arctic marine
mysids, and euphausids). They have a broad circumpo-
mammals. This includes data that were produced before
lar distribution and prefer annual, landfast ice, but are
1997 and summarized in the first AMAP POPs assess-
also found in multi-year ice. No clear-cut boundaries are
ment and further studies since that time. The focus on
known to separate ringed seal stocks in marine waters.
marine mammals comes in part because these animals,
Adults are believed to be relatively sedentary, but sub-
in particular seals and whales, are important compo-
adults sometimes disperse over long distances (Reeves,
nents of the diet of many Arctic societies. Marine mam-
1998). Ringed seals are a key component of the diet of
mals also occupy a range of trophic positions, and a
polar bears and the Inuit of Canada and Greenland.
number of species (e.g., polar bears) are apex predators,
Results of studies completed since the previous AMAP
and thus have high levels of OCs. Therefore, more than
POPs assessment are in general agreement with geo-
for any other group of animals, is concern about OCs
graphical trends reported previously for ringed seals (de
greatest in marine mammals, both with respect to effects
March et al., 1998). That is, PCB and DDT concen-
on the animals themselves and transfer to humans.
trations increase from west to east, with levels being
All relevant data on OCs and organotin compounds
lowest in ringed seals from the Chukotka Peninsula
in marine mammals that have become available since the
(Lavrentiya) (RAIPON/AMAP/GEF Project, 2001) and
previous AMAP assessment (de March et al., 1998) are
Alaska (Hoekstra et al., 2003a; Kucklick and Krahn,
reviewed here. It must be emphasized that the spatial
2002), intermediate in ringed seals from the eastern
trends of persistent OCs discussed below in this section
Canadian Arctic (Muir et al., 2000b; Fisk et al., 2002d),
are often qualitative because they are based on evalua-
higher in seals from Svalbard and the White Sea (Wolk-
tions of means and ranges of concentrations from differ-
ers et al., 1998b; Kostamo et al., 2000; Muir et al.,
ent studies. In the case of the sums of groups of com-
2002b), and highest in seals from the Kara Sea near Dik-
pounds, such as PCBs and chlordanes, some laboratories
son (Nakata et al., 1998a) (Figure 4 · 45). Between Chu-
have included more congeners or components than oth-
ers in PCB and CHL results. Rigorous comparisons
Concentration in ringed seal blubber,
ng/g lw
between locations also require information on age, sex,
2000
blubber thickness, nutritional status, collection season,
1500
and reproductive status of the animals, all of which can
have an important influence on contaminant concentra-
1000
tions. This information has been collected for many lo-
500
cations, but used only qualitatively in this assessment of
0
spatial trends between studies.
DDTs PCBs
A considerable body of data has been collected on
pinnipeds and cetaceans (both mysticetes and odonto-
cetes) since the previous AMAP POPs assessment (de
March et al., 1998). All relevant data that have become
available since the previous AMAP assessment are in-
cluded here for pinnipeds (Annex Table 12) and ceta-
ceans (Annex Table 13). Data for individual toxaphene
congeners are reported in Annex Table 15, while data
for individual PBDEs are reported in Annex Table 17,
and data for PCDD/Fs, non-ortho PCBs (nPCBs) and
toxic equivalents (TEQs) are reported in Annex Table
16. Although the current assessment primarily includes
data and publications since 1996, some reports included
here do contain data collected prior to this time, if they
were not considered in the previous AMAP assessment.
As in the previous AMAP assessment, by far the most
Figure 4· 45. Mean (± 95% CI) concentrations of PCBs and DDTs
frequently determined OC compounds in marine mam-
in female ringed seal blubber (Krahn et al., 1997; Muir et al.,
1999c; 2001c; 2002c; Muir and Johansen, 2001; Denmark, 2002;
mals are still PCBs (as congeners) and DDT-related com-
Fisk et al
4.4.6.1.1
., 2002c; Hoekstra, 2003a; Kucklick and Krahn, 2002;
pounds. Chlordane-related compounds, HCHs and HCB,
Nyman et al., 2002; Nakata et al., 1998a; RAIPON/AMAP/GEF
are somewhat less well represented, while other chloro-
Project, 2001).
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
101
Concentration
OC pesticides were quantified in the blubber of ringed
in ringed seal blubber,
seals from seven sites within Nunavik and Labrador, in
ng/g lw
1998 and 1999 (Muir et al., 1999c; 2000c) (Annex
500
400
Table 12). For comparison among regions, three sites
within Ungava Bay were combined (Kuujjuaq, Kangir-
300
suk and Kangiqsualujjuaq), as were two sites in the
200
100
Hudson Strait (Salluit and Quaqtaq). The two sites in
0
Labrador (Nain and Makkovik) were treated separately.
CHLs HCHs
Average blubber concentrations of PCBs, the major
OC contaminants in seals from these four locations,
ranged from 572 to 1042 ng/g ww in males, and from
512 to 730 ng/g ww in females (Muir et al., 2000c). The
highest levels in males were found in samples from the
more westerly locations of Ungava Bay and Hudson
Strait, while the highest average levels in females oc-
curred in samples collected at Nain. DDT-related com-
pounds were also prominent contaminants in ringed seal
blubber, with average concentrations ranging from 198
to 884 ng/g ww in males. Statistical analysis did not re-
veal any significant differences in concentrations of
PCBs or DDTs among the four locations for females.
For males, PCB, DDT, and HCH concentrations
were significantly higher in samples from Ungava Bay,
after adjusting for age. There was a significant interac-
Figure 4· 46. Mean (± 95% CI) concentrations of CHLs and HCHs
tion, however, between age and location (i.e. a differing
in female ringed seal blubber (Krahn et al., 1997; Muir et al.,
relationship of age with concentrations of the OCs) for
1999c; 2001c; 2003; Muir and Johansen, 2001; Denmark, 2002;
males, which may have affected the results. In general,
Fisk et al., 2002c; Hoekstra, 2003a; Kucklick and Krahn, 2002;
levels of PCBs and DDTs in ringed seal blubber from
Nyman et al., 2002; Nakata et al., 1998a; RAIPON/AMAP/GEF
this study were comparable to those found in ringed seal
Project, 2001).
blubber at other eastern Canadian Arctic locations (Weis
kotka and the Kara Sea, there are no data for seals in the
and Muir, 1997; Muir, 1998; Muir et al., 1999b), in-
Russian Arctic, representing a large geographical gap.
cluding those from the more northerly region of the
Levels of CHLs are fairly consistent across the Arctic,
Northwater Polynya in northern Baffin Bay (Fisk et al.,
while HCH concentrations are highest in Alaska and
2002d). Results for Fisk et al. (2002d) were also in the
decrease from west to east (Figure 4 · 46).
range reported for ringed seals from western-central and
Within Alaska, Kucklick and Krahn (2002) reported
northeastern Greenland (Muir and Johansen, 2001;
that PCB and OC pesticide concentrations measured in
Denmark, 2002) (Annex Table 12). After removing the
ringed seals collected between 1988 and 1998 generally
influence of age, sex, and blubber thickness, PCB and
decreased from Barrow to the more westerly site at
OC pesticide concentrations did not differ in ringed
Nome (Annex Table 12). After adjusting for the effects
seals from the east and west side of the Northwater
of age and blubber thickness, females from Barrow were
Polynya, likely due to the relatively small distance be-
found to have higher concentrations of PCBs, DDTs,
tween these two sites (Fisk et al., 2002d). Concentra-
CHLs, and dieldrin, while in males, only HCH con-
tions of DDTs and PCBs in seals from this region
centrations were higher in seals from Barrow. Only HCB
were lower than those reported for this species in Sval-
and mirex were not significantly different between the
bard, Norway (Wolkers et al., 1998b; Kleivane et al.,
two locations for either sex. There was general agree-
2000; Severinsen et al., 2000) (Annex Table 12). In con-
ment amongst studies between PCB and OC pesticide
trast, HCH concentrations in Canadian and Alaskan
levels observed in Barrow ringed seals (Hoekstra et al.,
ringed seals were higher than those reported for ringed
2003a; Kucklick and Krahn, 2002), and these levels
seals from the European Arctic. These geographical
were comparable to those measured recently in ringed
trends are consistent with past compilations of circum-
seals from the western Canadian Arctic (de March et al.,
polar data for ringed seals (Muir et al., 2000b) and polar
1998; Muir et al., 1999b) (Annex Table 12). For exam-
bears (Norstrom et al,. 1998).
ple, the geometric mean of DDTs in female seals from
Levels of PCBs found in Svalbard ringed seals (Wol-
Resolute was 340 ng/g ww (range of 163 -540 ng/g)
kers et al., 1998b; Kleivane et al., 2000; Severinsen et
(Muir et al., 2000b) versus 408 ng/g ww in the Barrow
al., 2000; Nyman et al., 2002) were in good agreement,
seals (range of 274 - 652 ng/g) and 178 ng/g ww (range
and were at least twice as high as those in seals from the
of 143 - 387 ng/g) in the seals from Nome.
Canadian Arctic (Annex Table 12), despite the smaller
Further east, ringed seals from Holman, NWT, (Hoek-
number of congeners included in PCBs for the Svalbard
stra et al., 2003a) had levels of PCBs and OC pesticides
seals. The predominant PCB congeners in the Kongs-
that were in general agreement with, and intermediate
fjorden (Svalbard) ringed seals were 153, 138, 99, 180 and
between, levels found in ringed seals from further west
101 (Wolkers et al., 1998b). The observed PCB patterns
(Alaska) (Hoekstra et al., 2003a; Kucklick and Krahn,
were very similar to patterns in seals from other studies
2002) and further east (eastern Canadian Arctic) (Muir
(Muir et al., 1988; Luckas et al., 1990; Beck et al.,
et al., 2000b; Fisk et al., 2002d). A variety of PCB and
1994), suggesting a similar biotransformation capacity.
102
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Further east, concentrations of PCBs, DDTs, and
Concentration in ringed seal blubber,
HCB, quantified in the blubber of ringed seals from the
ng/g lw
40
White Sea (Kostamo et al., 2000; Muir et al., 2003)
(Annex Table 12), were comparable to or higher than in
30
ringed seals from Svalbard, but lower than reported for
this species in the more easterly Kara Sea (Nakata et al.,
20
1998a). Within the White Sea, Muir et al. (2003) found
10
higher levels in seals sampled at Dvina Bay, near the city
of Archanglesk, in comparison to those from the more
0
northerly and less industrialized region of Gorlo Basin
Parlar 26
Parlar 50
(Annex Table 12). The high levels in the White Sea
ringed seals are likely influenced by local point sources,
as some parts of the White Sea are heavily industrialized.
Levels in White Sea ringed seals were also much lower
than levels in two freshwater sub-species of ringed seals
living in Lake Saimaa, Finland, (P. h. saimensis) and
Lake Ladoga, Russia, (P.h. ladogensis), (Kostamo et al.,
2000). Kostamo et al. (2000) found that the PCB con-
gener composition in blubber from the White Sea seals
resembled a mixture of Aroclor 1254 and 1260. They
also reported that the DDT: PCB ratio in the White
Sea ringed seals ranged from 0.96 to 1.49 (Kostamo et
al., 2000), which is similar to the results from ringed
seals in the east-central Canadian Arctic (Muir et al.,
Figure 4· 47. Mean (± 95% CI) concentrations of toxaphene Parlar
1988). The higher levels found in the Kara Sea seals may
26 and Parlar 50 in female ringed seal blubber (Wolkers et al.,
be due to OC inputs from the Ob and Yenisey Rivers,
1998b; Muir et al., 1999c; 2003; Hoekstra, 2003a).
which have been shown to be major sources of OCs to
the Arctic Ocean via river water and sediments (de
105, 126, 118, 114, 156, and 169) ranged from 14.9 to
March et al., 1998) (Section 4.3.1.1).
32.7 ng/g ww, with congeners 118, 105 and 156 being
Total toxaphene levels in ringed seal blubber were
the most predominant. Mean (± standard deviation) lev-
generally lower, moving eastward from Barrow, Alaska,
els of these were lower in female (15.4 ± 0.8 ng/g ww)
(mid- to high hundreds of ng/g lw) to the Hudson Strait
than male (26.7 ± 8.0 ng/g ww) ringed seals. TEQs for
and Ungava Bay (Canada) (low hundreds of ng/g),
non- and mono-ortho PCBs in males and females were
Greenland and the Barents Sea (tens of ng/g), and then
0.624 ± 0.144 pg/g lw and 0.508 ± 0.088 pg/g lw, respec-
slightly higher (low hundreds of ng/g) in White Sea
tively, most of which was accounted for by congener 126
ringed seals (Annex Table 12) (Wolkers et al., 1998b;
(Helm et al., 2002) (Annex Table 16). For ringed seals
Muir and Johansen, 2001; Denmark, 2002; Hoekstra et
from Holman, TEQs based on non- and mono-ortho
al., 2003a; Muir et al., 2003). On a congener basis, Par-
PCBs in blubber from 2000 ranged from 4.3 to 91 pg/g
lar 26 levels were highest in ringed seals from Hudson
ww, with the PCBs contributing most to the TEQs
Strait and Ungava Bay in the Canadian Arctic, followed
(Ikonomou, 2002). Ringed seals from the Kara Sea had
by those in seals from Alaska and the White Sea and
total non- and mono-ortho PCB concentrations (sum of
then Svalbard, with the lowest levels in seals from west-
CBs 77, 105, 118, 126, 156, and 169) of approximately
ern Greenland. Levels of Parlar 50 were highest in seals
670 ng/g ww in blubber (Nakata et al., 1998a). The
from Svalbard and Hudson Strait and lower in seals
TEQ for these CB congeners was approximately 144
from Ungava Bay and western Greenland (Annex Table
pg/g ww (160 pg/g lw), and CB126 contributed most,
15; Figure 4 · 47).
followed by CB118. Blubber from ringed seals and spot-
In ringed seal blubber from northern Quebec, octa-
ted seals (Phoca largha) collected from the Chukotka
and nonachlorobornanes were the major homologue
Peninsula (Lavrentiya) area were analyzed for PCDD/Fs
groups (Muir et al., 2000d) (Annex Table 15). Toxa-
(RAIPON/AMAP/GEF Project, 2001). TEQs were 1.1
phene Parlars 39, 40, and 42 were also identified in the
pg/g ww for ringed seals and 1.3 pg/g ww for spotted
blubber of ringed seals from Arviat, Nunavut (formerly
seals.
in the NWT) (Loewen et al., 1998), marking the first
time that Parlar 42, the most toxic congener in technical
Harp seals
toxaphene, has been found in any significant concentra-
Harp seals are an Atlantic species, inhabiting Arctic and
tions in a marine mammal. Ringed seals from Kongsfjor-
subarctic waters. They feed primarily on small marine
den, Svalbard, (Wolkers et al., 1998b) showed no effect
fish and, secondarily, on crustacean macroplankton.
of sex, age or total blubber on toxaphene levels. Slightly
Three separate harp seal populations undergo annual
higher concentrations of toxaphene Parlars 26, 50, and
migrations between southerly breeding sites and their
62 were found in male than female ringed seals from
northern feeding grounds, both at the edge of the pack
Kongsfjorden (Føreid et al., 2000).
ice. Harp seals are not a common dietary item of north-
Blubber from ringed seals collected in 1993 near
ern human populations.
Pangnirtung, Nunavut, were analyzed for non- and
Little information has become available on contami-
mono-ortho PCBs (Helm et al., 2002). Total non- and
nants in harp seals since the previous AMAP assess-
mono-ortho PCB concentrations (sum of CBs 77, 81,
ment. However, recent studies are available for seals
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
103
from Svalbard and the White Sea. Data are available for
harp and ringed seals in the White Sea has demonstrated
PCBs (Wolkers et al., 1999), DDTs, HCB, HCHs, as well
that levels of toxaphene are higher there than in west
as cyclodiene pesticides such as dieldrin, endrin, and the
Svalbard or Greenland (Savinova et al., 2000b). Studies
chlordanes (Wolkers et al., 2000) (Annex Table 12). The
of sediments in the Kola Bay area have demonstrated
levels of PCBs and most pesticides, especially the DDTs,
that elevated toxaphene is present in sediments in Po-
for sub-adult (4 years) harp seals from the ice edge,
lamy, a harbor north of Murmansk (Savinova et al.,
east of Svalbard, were relatively low compared to those
2000a), possibly associated with past use for insect con-
reported in other harp seal studies. This was probab-
trol on ships.
ly, in part, because animals were sampled during the
summer, when the total blubber content is high com-
Harbour and grey seals
pared to the spring (Wolkers et al., 1999; 2000). In con-
Harbour seals are one of the most broadly distributed
trast to this, levels of PCBs and OC pesticides quantified
pinnipeds, inhabiting temperate, subarctic, and in some
in older adult males from the same area (Kleivane et al.,
cases Arctic waters, in the north Atlantic and north Pa-
2000) were substantially higher than previously re-
cific. They are a relatively sedentary species that feed op-
ported in this species (Oehme et al., 1995c; Kleivane et
portunistically on a wide variety of fish, cephalopods,
al., 1997).
and crustaceans (Bigg, 1981). Grey seals are a more mo-
Levels of PCBs and OC pesticides were quantified in
bile pinniped that occur in Atlantic Canada, around Ice-
harp seals from the southern ice area located north of
land, the Faroe Islands, Great Britain, Norway, the Kola
the White Sea in 1993 and were also elevated, but to a
Peninsula, and the Baltic Sea (Bonner, 1981). They con-
lesser extent than in the mature Svalbard males. All ani-
sume a wide variety of fish, as well as some crustaceans
mals in the Svalbard group were lean specimens in late
and cephalopods, and generally feed further offshore
molt, while those from the White Sea were sampled
and in deeper waters than do harbour seals.
early in the molt. The Svalbard seals had significantly
Blubber concentrations of PCBs, DDTs, chlordanes,
thinner blubber than the seals sampled outside of the
dieldrin, and HCB in harbour seals from Prince William
White Sea (Kleivane et al., 2000). Thus, the dramatic de-
Sound (Alaska) in 1993 (Krahn et al., 1997) (Annex
crease in the fat reservoir in adult seals during the molt-
Table 12) were similar to corresponding data for this
ing period, when feeding is at a minimum or non-exis-
species from the same region in 1989-1990 (Varanasi et
tent, clearly resulted in a significant concentration of
al., 1993). Their levels of PCBs and DDTs were about
PCBs, DDTs, and chlordanes in the remaining blubber
twice those of bearded (Erignathus barbatus) and ringed
of these seals. To the south, blubber concentrations of
seals from the more northerly region of Norton Sound in
PCBs, DDTs, chlordanes, and HCB in harp seals from
the Bering Sea (Alaska) (Krahn et al., 1997). These dif-
the Gorlo Basin of the White Sea in 1998 (Muir et al.,
ferences may be explained by the higher trophic position
2003) were comparable to those reported for harp seals
occupied by harbour seals compared to ringed or bearded
sampled east of Svalbard in 1997 (Wolkers et al., 1999;
seals, or by the greater anthropogenic activity in Prince
2000) and were on the low side of the range of levels re-
William Sound compared to Norton Sound.
ported for this species in the Kleivane et al. (2000) study.
Ruus et al. (1999) quantified PCBs, DDTs, CHLs,
Mean POP levels in young harp seals sampled in 1992
HCHs, and HCB in harbor and grey seals from Jar-
(Muir et al., 2003) were generally higher compared to
fjord, northern Norway (Annex Table 12). Levels of
those sampled in 1998, and were comparable to those
PCBs, DDTs, and CHL levels were up to an order of
reported for seals north of the White Sea in 1993
magnitude higher than in harbour seals from Alaska,
(Kleivane et al., 2000). It is not clear if this is an indica-
while HCB levels were comparable between the two re-
tion of declining levels with time or variability in biolog-
gions (Krahn et al., 1997). Interspecies differences in lev-
ical parameters, such as blubber thickness.
els of HCHs and HCB, as well as PCB congener pat-
Toxaphene levels in juvenile harp seals from eastern
terns (e.g., CBs 101, 118, 153, and 180) between Nor-
Svalbard in 1997 (Wolkers et al., 2000) were compara-
wegian harbor and grey seals, may be explained by dif-
ble to those found in adult females and juveniles from
ferent dietary preferences and metabolic capacities. -
the White Sea in 1998 (Muir et al., 2003). Interestingly,
HCH was the most abundant of the HCH isomers in
in contrast to results from seals in other areas (Muir et
both harbor and grey seals from Jarfjord.
al., 1992a; Wolkers et al., 1998b), toxaphenes were the
Grey seals sampled in 1993 -1995 at the Faroe Is-
predominant compounds in young harp seals from east-
lands, in connection with a study of their summer diet
ern Svalbard, exceeding PCB concentrations. Toxaphene
(Mikkelsen, 1998), were analyzed for OCs in pooled
concentrations in these young harp seals (Wolkers et al.,
samples initially, and later separately in 30 individuals
2000) were also more than 20 times higher than in juve-
(Larsen and Dam, 1999; Dam, 2001). The pooled sam-
nile ringed seals from the west coast of Svalbard (Wolk-
ples were composed of a total of 45 individuals: the
ers et al., 1998b). Although there may be species-specific
pools were composed of adult males (n = 4, age > 8 yr);
differences, the high toxaphene levels found in the seals
adult females (n = 20, pregnant individuals); and, juve-
from the east coast of Svalbard (Barents Sea) as com-
niles (n = 21, 15 females and six males, age > 2 yr and < 4
pared to the seals from the west coast of Svalbard, may
yr). As in the Jarfjord study, -HCH was the dominant
indicate that, in spite of a ban on the use and production
HCH isomer, but was pronounced only in the group of
of these compounds in the western world (Voldner and
juveniles. In the adult female group, the HCH isomers
Li, 1993), the Barents Sea area is continuously exposed
were found in similar or slightly decreasing concentra-
to toxaphenes. Thus, in addition to atmospheric long-
tions in the following order: -HCH
-HCH
-
range transport, another source of toxaphenes may con-
HCH. The single OC occurring in the highest concentra-
tribute to the high levels found. Furthermore, a study of
tion among the adults was CB153, followed by p,p'-
104
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Concentration in Steller sea lion scat,
ng/g lw
2000
1000
A L A S K A
0
PCBs
DDTs
G u l f o f A l a s k a
Figure 4· 48. Concentrations of PCBs and DDTs in Steller sea lion scat composites collected from rookeries or haulouts in 1998 and 2000
(Beckmen, 2002).
DDE and CB180. CB153 concentrations in blubber were
ww), which is an order of magnitude higher than the
4900 ng/g ww and 540 ng/g ww in males and females,
other regions. CHL and mirex concentrations were
respectively. In the juveniles, this sequence was different
similar in seals from all regions. HCB and HCH concen-
with p,p'-DDE > CB153 > CB 138+163, with CB153 at
trations were highest in seals from Barrow, Alaska. HCB
1200 ng/g ww in blubber. The analyses of the 30 indi-
levels were comparable in seals from Chukotka, Sval-
viduals gave the `typical' pattern of decreasing OC level
bard, White Sea, and Norton Sound (Annex Table 12).
in females with age and a parallel increase in males. The
Toxaphene levels in White Sea bearded seals were com-
results further revealed that in the female seals there
parable to those in ringed and harp seals from the same
were significant correlations between toxaphene (as Par-
region, as well as levels in northwestern Greenland wal-
lar 50 concentrations) and CB 153 but not among the
rus, Barents Sea harp seals, and ringed seals from Bar-
males. There were, however, highly significant correla-
row, Alaska (Muir et al., 2000d; 2003; Wolkers et al.,
tions between CB 153 and p,p'-DDE and trans-nona-
2000; Hoekstra et al., 2003a). The high levels in the
chlor in both sexes.
White Sea bearded seals are an example of the effects of
point sources in the Arctic, as some parts of the White
Bearded seals
Sea are heavily industrialized. Blubber from bearded
Bearded seals from Norton Sound and Barrow, Alaska
seals collected from the Chukotka Peninsula (Lavren-
had relatively low OC concentrations in blubber com-
tiya) area was analyzed for PCDD/Fs; the TEQ was 0.97
pared to other pinniped species from that region and in
pg/g ww (RAIPON/AMAP/GEF Project, 2001) (An-
the broader Arctic context (Krahn et al., 1997; Hoekstra
nex Table 16).
et al., 2003a) (Annex Table 12). This may be primarily
because bearded seals remain in the northern Alaskan
Steller sea lions
seas, a region with limited anthropogenic activity, and
Based on samples from eighteen rookeries in 1998 and
consume lower trophic-level prey, including a wide vari-
2000, Beckmen (2002) determined that Steller sea lions
ety of invertebrates, such as decapod crustaceans and
sampled from the eastern Aleutian Islands (part of the
mollusks (Kelly, 1988; Krahn et al., 1997). Blood sam-
endangered western Alaskan stock) excrete significantly
ples from bearded seals from Svalbard had comparable
higher levels of PCBs and DDTs in their feces (mainly
OC concentrations on a lipid weight basis to the
adult females) compared to Steller sea lions in southeast
Alaskan seals, except for HCH, but on the Chukotka
Alaska (Figure 4 · 48). Levels of POPs in blubber biopsies
Peninsula (Lavrentiya), blubber samples had generally
were not significantly different between pups and juve-
lower OC concentrations compared to Alaska and Sval-
niles in southeast Alaska and Prince William Sound in
bard (RAIPON/GEF/AMAP Project, 2001). In contrast
the Gulf of Alaska (Annex Table 12). Unfortunately,
to bearded seals from Alaska, Chukotka, and Svalbard,
no blubber biopsies were available from the eastern
those from the White Sea (Muir et al., 2003) had very
Aleutian Islands or further west in the range. These find-
high PCB and DDT levels (approximately 3000 ng/g
ings indicate that PCBs are present in the food web ex-
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
105
ploited by Steller sea lions in Alaska, at least as far west
tively little is known about levels of OCs in walrus com-
as the eastern Aleutian Islands. In southeast Alaska
pared to seals and beluga. The previous AMAP report
where PCB levels were intermediate, the population
noted that although walrus generally have low OC con-
has increased in recent years. The relatively high levels
centrations in blubber, some individuals feed at higher
for the eastern Aleutian Islands, in comparison to the
trophic levels than others and, as a result, have much
nearby Gulf of Alaska, are of interest, as they suggest
higher contaminant concentrations (de March et al.,
either a local source or a strong influence from the Be-
1998). These walrus are believed to be including ringed
ring Sea.
seals in their diet (Muir et al., 1995b). Since then, stud-
ies have examined levels of OCs in walrus from the
Northern fur seals
Russian and Alaskan Bering Sea, eastern Hudson Bay,
Breeding rookeries for more than 72% of the world's
and eastern and western Greenland (Muir and Kwan,
population of northern fur seals are located on the two
2000; Muir et al., 2000e; Seagars and Garlich-Miller,
largest Pribilof Islands, St. Paul and St. George (Alaska)
2001; Kucklick and Struntz, 2002;).
in the Bering Sea (Loughlin et al., 1994). A preliminary
Levels of PCBs and OC pesticides such as DDTs,
study demonstrated that young northern fur seal dams
HCHs, and chlordanes in the blubber of Pacific walrus
(presumably primiparous) in the early post-partum pe-
(Odobenus rosmarus divergens) sampled across the Rus-
riod on St. George and St. Paul Islands, had significantly
sian and the Alaskan Bering Sea (Seagars and Garlich-
higher OC levels in their milk and blood than old (mul-
Miller, 2001; Kucklick and Struntz, 2002) were compa-
tiparous) dams (Beckmen et al., 1999). Higher milk OC
rable to the relatively low levels previously reported in
exposure to the suckling pups was correlated with sig-
Bering Sea walrus (Galster and Burns, 1972; Taylor et
nificantly higher OC levels in blood of the neonatal pups
al., 1989) (Annex Table 12). As in earlier studies, DDT
(Beckmen et al., 1999). In 1996, 50 perinatal pups were
compounds were essentially absent from walrus blubber
captured for blood sample collection (during the ten-day
in this region, while heptachlor epoxide was detected for
perinatal period and referred to as neonates), and 43
the first time at low ng/g levels. In the Bering Sea walrus,
were re-sampled 29 to 51 days later (`pups'). Mean
oxychlordane dominated CHLs, while -HCH domi-
blood OC levels were higher in neonates than at recap-
nated HCHs (Kucklick and Struntz, 2002). Addition-
ture, and again, neonates of young dams had higher
ally, significantly higher levels of PCBs occurred in
mean blood OC levels than neonates of older dams (An-
adult males (450 ng/g ww) than females (160 ng/g ww),
nex Table 12). The traditionally harvested and consumed
and significantly higher oxychlordane levels occurred in
subadult males have lower concentrations of PCBs and
males than females of any age. No differences were de-
DDTs than do adult females or pups (Annex Table 12).
tected between sexes for HCH and dieldrin (Seagars
PCB and DDT concentrations in subadult males from
and Garlich-Miller, 2001).
another study (Krahn et al., 1997) were comparable to
OC levels in walrus from eastern Hudson Bay (north-
levels reported by Beckmen et al. (1999). OC concentra-
ern Quebec) (Atlantic walrus, O. r. rosmarus) were much
tions are lowest in fetal blubber but data were only
lower than those found in earlier studies from the same
available from two individuals. Pups showed some re-
area (Muir and Kwan, 2000; Annex Table 12), most
markably high OC concentrations in blubber, especially
likely because the earlier studies sampled walrus that
p,p'-DDE, but there is a large variance in blubber lipid
were seal-eaters (Muir et al., 1995b). Nonetheless, con-
content due to nutritional status.
centrations of many OCs were comparable to those in
PCB, DDT, chlordane, HCB, and dieldrin levels in
recent reports for walrus from other nearby regions such
subadult northern fur seals from St. Paul Island were
as Foxe Basin (Muir et al., 1995b). Levels of PCBs
comparable to, or higher than, concentrations in ringed
were similar to those in walrus from the Bering Sea and
and bearded seals from the Bering Sea and harbour seals
northwestern Greenland, while DDT levels were simi-
from Prince William Sound (Gulf of Alaska) (Krahn et
lar to those in walrus from northwestern Greenland
al., 1997). This can be partially explained by the fur
(Muir et al., 2000e). HCHs and HCB were also de-
seals' consumption of higher trophic-level prey such as
tected in concentrations similar to those in walrus from
pollock, herring, and squid (Wynne, 1993; Krahn et al.,
the Bering Sea and eastern and northwestern Greenland
1997), and, perhaps more importantly, by their exten-
(Muir et al., 2000e) (Annex Table 12). In the case of
sive annual migration. This species migrates as far south
CHLs, levels in eastern Hudson Bay walrus were higher
as California and through the eastern Pacific as far as
than those in the Bering Sea and northwestern Green-
Japan, where these animals potentially feed on prey that
land, but lower than in eastern Greenland walrus (Muir
are much more highly contaminated than prey in the
et al., 2000e).
waters of the southern Bering Sea or the Gulf of Alaska.
An examination of spatial trends in levels of OC
Concentrations of non- and mono-ortho PCBs fol-
compounds in two separate stocks of walrus from
lowed the general pattern for PCBs with highest TEQs
Greenland found lower concentrations in the northwest-
found in pups (32 pg/g ww) as compared to adults and
ern Greenland animals, and much higher levels of all
subadults (17-21 pg/g ww) (Beckmen, 1999) (Annex
OCs, except HCH isomers and mono/dichlorobiphenyls
Table 16).
in samples from eastern Greenland (Muir et al., 2000e)
(Annex Table 12). PCB levels averaged 246 ng/g ww in
Walrus
male walrus from northwestern Greenland, and 2860
Walrus are long-lived benthic feeders and, as such, an
ng/g ww in samples from eastern Greenland. However,
important indicator species for bioaccumulating con-
DDT isomers showed the most difference between the
taminants in benthic marine food webs. Although they
two sites, with p,p'-DDE and p,p'-DDT being 50 and 69
have an important role in native traditional hunts, rela-
times higher, respectively, in the eastern Greenland
106
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
walrus. Toxaphene levels in walrus in northwestern
Concentration in minke whale, ng/g lw
Greenland were lower than those from eastern Green-
5000
land, but were consistent with levels reported in ringed
PCBs
4000
DDTs
seals from Barrow, Alaska, ringed, harp, and bearded
seals from the White Sea, and harp seals from the Bar-
3000
ents Sea (Wolkers et al., 2000; Hoekstra et al., 2003a;
2000
Muir et al., 2003). The eastern Greenland walrus
showed a pattern of OCs characteristic of seal-eating an-
1000
imals, although they may have been consuming other
0
prey as well. Despite the apparent differences in prey, the
higher levels of OCs in eastern Greenland compared to
4
-endosulfan
the northwestern Greenland animals are consistent with
3
results for polar bears, seals and gulls from the same
regions.
2
Butyltins in pinnipeds
1
Mean butyltin (BTs) concentrations of 17 ng/g ww
were found in liver tissue from Steller sea lions sampled
0
at the Aleutian Islands (Alaska) between 1976 and 1985
120
(Kim et al., 1996a). In these animals, TBT concentra-
-HCH
tions ranged from 1.9 to 5.6 ng/g ww, while DBT and
-HCH
90
MBT concentrations ranged from below detection limits
to 20 ng/g ww and 7.1 ng/g ww, respectively. DBT was
60
the dominant component in the liver samples, which is
in contrast to fish (their prey), in which TBT levels are
30
highest, irrespective of the species and sampling site
(e.g., Suzuki et al., 1992; Takayama et al., 1995). This
0
implies that Steller sea lions are capable of metabolically
12.5
transforming at least some of the TBT residues they con-
Mirex
10.0
trans-chlordane
sume into DBT and MBT (Kim et al., 1996a). There was
no evidence of age- or sex-dependent accumulation of
7.5
butyltin residues in Steller sea lions, and no evidence of
5.0
increasing concentrations of DBT and TBT between
1976 and 1985 (Kim et al., 1996a). Butyltin concentra-
2.5
tions in Svalbard ringed seals were 1.5 ng/g ww for
0
MBT, 3.1 ng/g ww for DBT, and TBT was not detected
150
(Berge et al., 2002). TBT and its metabolites, DBT and
cis-nonachlor
MBT, were non-detectable (sub ng/g) in ringed seal blub-
120
trans-nonachlor
ber and liver from Labrador and northern Quebec (Muir
90
et al., 1999c; 2000c).
60
4.4.6.2. Cetaceans
30
4.4.6.2.1. Mysticetes
0
WG
CG
CM
EN
EC
ES
EB
Minke whales
North Atlantic minke whales are trans-Atlantic, as well
as polar to north temperate in range, and are capable of
large-scale migrations. They feed at a lower trophic level
than polar bears, odontocetes, and some seals, eating pri-
EB
marily capelin, herring, Atlantic cod, and krill (Larsen
ES
and Kapel, 1981; Nordøy and Blix, 1992; Skaug et al.,
WG
CG
CM
1997).
EC
Concentrations of PCBs and major OC pesticides
quantified in the blubber of minke whales from seven
EN
regions across the north Atlantic and European Arctic
ranged widely, but generally increased from west to east
(Hobbs et al., 2003) (Annex Table 13, Figure 4 · 49).
Contaminant concentrations suggested that western
Figure 4· 49. Sex-adjusted, geometric mean (± 95% CI) concentra-
and southeastern Greenland minke whales represent
tions of PCBs, DDTs, and geometric mean concentrations of -
one group of whales, which are distinct from both Jan
endosulfan, -HCH, -HCH, mirex, trans-chlordane, cis-nona-
Mayen minkes and those from other more easterly
chlor, and trans-nonachlor in minke whales from several areas in
the North Atlantic region. Areas are IWC `small areas' (WG: west
regions. Although some differences were detected in
Greenland, CG: southeast Greenland, CM: Jan Mayen, EN: North
PCB and OC pesticide concentrations between Jan
Sea, EC: Vestfjorden/Lofoten, ES: Svalbard, EB: eastern Barents
Mayen whales and those from other regions, overall,
Sea) (Hobbs et al., 2002a).
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
107
Jan Mayen whales were more similar to minke whales
Grey whales (Eschrichtius robustus)
from the easterly regions, and generally appeared to be
The eastern grey whale stock makes an annual round-
most similar to those from Svalbard and Vestfjorden/
trip migration between their breeding grounds in sub-
Lofoten.
tropical waters (e.g., off Baja California and the south-
Contaminant levels in minke whales from the North
ern Gulf of California) and their predominant feeding
Sea and the Kola Peninsula region of the Barents Sea
grounds in the northern Pacific Ocean. Although the
were relatively distinct from other groups of whales, and
majority of feeding occurs in the Bering and Chukchi
were often higher compared to other areas. For ex-
Seas around Alaska (Highsmith and Coyle, 1992;
ample, North Sea minkes had higher concentrations of
Moore et al., 2000), some animals spend extended peri-
the current-use pesticides, lindane ( -HCH), -endosul-
ods in the spring and summer opportunistically feeding
fan, and trans-nonachlor, compared to Svalbard whales.
in the coastal waters of Washington, California, Oregon,
Minkes from the Kola Peninsula region of the Barents
and British Columbia. Grey whales feed primarily on
Sea had higher concentrations of PCBs, and a lower
benthic prey, such as ampeliscid amphipods, using suc-
DDT: PCB ratio compared to those from Vestfjor-
tion to engulf sediments and prey from the bottom, then
den/Lofoten, as well as marginally higher PCB concen-
filtering out water and sediment through their baleen
trations compared to the North Sea and Svalbard
plates and ingesting the remaining prey. This unique
whales. Therefore, although some mixing probably oc-
feeding method often results in the ingestion of sediment
curs between whales from the Kola Peninsula and Sval-
and other bottom materials. Thus, exposure to sedi-
bard and between whales from North Sea and Vestfjor-
ment-associated contaminants is possible if they feed in
den/Lofoten, there appears to be some separation be-
areas containing contaminated sediments and benthic
tween whales from these two sets of regions. Further-
invertebrates.
more, Skaare et al. (2001c) found significantly lower
PCB and DDT blubber concentrations of 17 grey
concentrations of PCBs in the dorsal blubber of adult fe-
whales sampled from the Chirikov Basin of the Russian
male minkes sampled near Spitsbergen (461 ng/g ww)
Bering Sea in October 1994 ranged from 110 to 1300
compared to adult females sampled in the North Sea
and 30 to 540 ng/g ww, respectively (Krahn et al., 2001;
(2190 ng/g ww) (Annex Table 13). Despite these distinc-
Tilbury et al., 2002) (Annex Table 13). All of the whales
tions, there was a general blurring in levels and patterns
sampled were juveniles, thus minimizing the influence of
of PCBs and OC pesticides in minkes from Jan Mayen,
length (i.e. related to age and developmental stage) on
Svalbard, Vestfjorden/Lofoten, the North Sea, and the
contaminant concentrations. Futhermore, no significant
Kola Peninsula region of the Barents Sea, suggesting that
differences in concentrations (lw) occurred by sex within
minke whales are quite mobile and feed in multiple areas
each group of whales sampled. Blubber from one grey
(Hobbs et al., 2003).
whale from the Chukotka Peninsula (Lavrentiya) was
Mean PCB, DDT, CHL, HCH, and HCB con-
analyzed for OCs including PCDD/Fs. PCB and DDT
centrations reported in minke whales from the northeast
concentrations were 196 ng/g ww and 93 ng/g ww, re-
Atlantic (western Spitsbergen, Lofoten/Vesteralen, Fin-
spectively, and TEQ based on PCDD/F was 1.8 pg/g ww
mark, Bjørnøya, and the Kola Peninsula) in 1992 (Klei-
(Annex Table 16) (RAIPON/AMAP/GEF Project, 2001).
vane and Skaare, 1998) were about two to three times
No other grey whale data are available for comparison.
higher than mean levels reported in the same general re-
However, on a wet weight basis, these levels are similar
gions by Hobbs et al. (2003). The lower contaminant
to PCB and DDT levels in other mysticetes. For ex-
levels in more recent minke samples (Hobbs et al., 2003)
ample, mean concentrations of PCBs in blubber of
may be attributable to changes in the availability of
bowhead whales (Balaena mysticetus) from Alaska
northeast Atlantic minke whale prey species. For exam-
(Hoekstra et al., 2002c), fin whales (Balaena physalus)
ple, in 1992, the diet of Svalbard minke whales was
from the north Atlantic (Aguilar and Borrell, 1994), and
dominated by capelin, while in subsequent years, follow-
minke whales from western Greenland (Hobbs et al.,
ing the collapse of the capelin stocks in 1992/1993, their
2003) were 359, 732, and 2290 ng/g ww, respectively.
diet was almost 100% krill (Haug et al., 2002).
Similarly, mean concentrations of DDTs in bowhead-,
Concentrations of PCDD/Fs and non- and mono-
fin-, and minke whales were 331, 633, and 650 ng/g ww,
ortho PCBs were also analyzed in dorsal blubber of fe-
respectively.
male minkes sampled near Svalbard and in the North
Sea (Annex Table 16). Total mean TEQs based on these
Bowhead whales
compounds were 24 pg/g ww (range 10-37 pg/g ww) for
The bowhead whale is a large mysticete found in Arctic
Svalbard and 67 pg/g ww (range 25-103 pg/g ww) for
waters. The largest population, the Bering Sea stock,
the North Sea whales (Skaare et al., 2001c). The major
migrates annually between the eastern Beaufort Sea-
contribution to the TEQs came from the non- and
Amundsen Gulf in summer and the Chukchi and north-
mono-ortho PCBs.
ern Bering Sea in the winter (Schell et al., 1989; Lowry,
Levels of total toxaphene showed considerably more
1993; Moore and Reeves, 1993). Blubber and liver tis-
geographic variability than PCBs (Hobbs et al.,
sue were collected during the Native subsistence harvest
2002a). Levels were highest in the North Sea whales,
of this species, which coincides with the migration be-
followed by those from Jan Mayen and west Svalbard.
tween the Beaufort and Bering Seas.
The lowest levels occurred in whales from either side of
OC concentrations in Alaskan bowhead whales re-
Greenland and from the Vestfjorden/Lofoten region of
ported by Hoekstra et al. (2002c) (Annex Table 13) were
Norway. Total toxaphene levels in minkes from the Kola
similar to values reported by Mössner and Ballschmiter
Peninsula region of the Barents Sea were intermediate in
(1997) and O'Hara et al. (1999). Hoekstra et al. (2002c)
comparison to the other sites (Hobbs et al., 2002a).
also reported mean concentrations of toxaphene in bow-
108
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
head whales for the first time. The bioaccumulation of
2000). The Cook Inlet stock generally had the lowest
PCBs and OC pesticides in bowhead whale blubber ap-
concentrations, while the eastern Beaufort Sea stock had
peared to change seasonally and was characterized by
the highest concentrations. This is somewhat surprising
differences in analyte metabolism. The proportions of
given that whales from the Cook Inlet stock reside in
individual OCs in bowhead blubber samples were re-
one of the most `urban' areas of Alaska, where anthro-
lated to the harvest season. Principal components analy-
pogenic contamination results from relatively higher
sis showed that whales harvested in the autumn of 1997-
density of human residents and commercial activities.
2000 had higher loadings for less chlorinated PCBs,
The eastern Chukchi Sea and eastern Beaufort Sea
toxaphene, and chlorobenzene congeners, which distin-
stocks could clearly be distinguished from the Cook
guished them from spring harvest specimens collected
Inlet stock by patterns of individual OC analytes, and
during 1998-2000 that had higher proportions of the
although there was some overlap between the males
more recalcitrant PCBs (CBs 153 and 180), p,p'-DDE,
and females of the Cook Inlet stock, these groups were
HCB and -HCH. The patterns of OC loadings found in
also generally separated (Krahn et al., 2000). These
bowhead whale blubber generally reflect the different
differences in contaminant patterns are indicative of dif-
levels of persistent OCs in the surface waters of the Be-
ferences in contaminant accumulation, which likely re-
et al.
ring and Beaufort Seas (Iwata et al., 1993; Hoekstra et
flects differences in habitat use and prey forage among
ubber
al., 2002c). Toxaphene levels in the Beaufort Sea bow-
the stocks.
askan
heads were comparable to those measured in minke
In the Canadian Arctic, PCBs were quantitatively the
astern
whales from western Greenland and the Norwegian Sea
most predominant POPs in the blubber of eastern Hud-
e ana-
(Hobbs et al., 2002a). Results reported by Hoekstra et
son Bay belugas, followed by DDT and chlordane-re-
rns of
al. (2002c) demonstrate that bowhead whales are ex-
lated compounds (Sang et al., 2000) (Annex Table 13).
DDTs,
posed to a variety of OC pollutants from lower trophic-
Higher concentrations of all major groups of OCs, ex-
t Lay
level prey items, and that seasonal variation in OC pro-
cept for HCHs, were observed in blubber of males
ubber
files coincides with the annual migration between the
(n = 8) as compared to females (n = 2). Data were too lim-
et al.,
Beaufort and Bering Seas. The influence of collection
ited to evaluate effects of age or animal condition on
good
season on OC bioaccumulation in blubber seen in their
contaminant levels. No other contaminant data for be-
or the
study suggests that OC concentrations change annually
luga blubber samples from the Hudson Strait area
2000).
in the whales, and that spatial differences in contami-
(Kangiqsujuaq) have been analyzed for comparison.
s con-
nant levels within the Bering-Chukchi-Beaufort region
Levels of major OC groups in male beluga blubber sam-
ranges
may be reflected in marine biota.
pled by Sang et al. (2000) were, however, similar to pre-
whales
vious reports for male beluga from eastern Hudson Bay
Table
(Nastapoka River) in the mid-1980s (Muir et al., 1990b),
4.4.6.2.2. Odontocetes
k Inlet
and much lower than levels in beluga from the southeast
oncen-
Belugas
Baffin beluga stock. Muir et al. (1990b) concluded that
rt Sea
The beluga or white whale is a small (up to 4.5 m long)
belugas sampled from the Kangiqsujuaq area of the
ations.
toothed cetacean (odontocete) that is circumpolar in dis-
Hudson Strait are from a population that inhabits east-
n that
tribution in the Arctic. Belugas feed near the top of the
ern Hudson Bay and southern Hudson Strait, and not
reside
marine food web on a variety of fish and invertebrates,
the southeast Baffin Island area. Innes et al. (2001) also
eas of
such as cephalopods and shrimp (Banfield, 1974), and
concluded that there are distinct differences in the OC
ntami-
are relatively long lived (>35 yr). They have a nearly
signature of southeast Baffin and Hudson Bay belugas.
r den-
continuous distribution across the Russian Arctic coast,
Comparisons between east Hudson Bay and west Hud-
mercial
but in the NE Atlantic Ocean they are limited to the
son Bay beluga are complicated by missing age estimates
a and
north coast of Norway, and in the Pacific Ocean, to the
and lipid content data for these whales (Hobbs et al.,
clearly
Okhotsk Sea (Kleinenberg et al., 1964). They are present
2002b) (Annex Table 13). With this in mind, it seems
Inlet
along the east and west coasts of Greenland and in
that the western Hudson Bay beluga may generally have
C ana-
North America, from Alaska across the Canadian west-
had higher PCB and OC pesticide concentrations than
e was
ern Arctic to a large population in Hudson Bay, and
the east Hudson Bay whales. This may be at least parti-
males
among islands in the eastern Canadian Arctic. Beluga
ally a result of the west Hudson Bay beluga having been
stock,
movements are extensive, seasonal and generally pre-
sampled six years before the east Hudson Bay whales.
sepa-
dictable. They come into coastal waters and estuaries in
OC levels for beluga from Kimmirut, Baffin Island were
These
mid-summer, and spend the winter offshore in pack ice
similar to, but somewhat higher than, levels in the east
and polynyas (Brodie, 1989).
Hudson Bay beluga (Annex Table 13). Non- and mono-
In a recent study by Krahn et al. (2000), samples of
ortho PCBs in beluga from the same region were ana-
beluga blubber from three of the five different Alaskan
lyzed by Helm et al. (2002), and levels ranged from 14.4
stocks (eastern Beaufort Sea, eastern Chukchi Sea and
to 294 ng/g ww, with CBs 118, 105, and 156 being the
Cook Inlet) were analyzed for concentrations and pat-
most dominant congeners. Total non- and mono-ortho
terns of OC contaminants. PCBs, DDTs, CHLs and
PCBs were lower in females (60.2 ± 40.3 ng/g ww) than
HCB levels in Point Lay (eastern Chukchi Sea) beluga
males (228 ±113 ng/g ww). TEQs in males and females
blubber (Wade et al., 1997; Hoekstra et al., 2003a)
were 1.73 ± 0.627 pg/g lw and 1.32 ± 0.909 pg/g lw re-
(Annex Table 13) were in good agreement with those re-
spectively, most of which was accounted for by congener
ported for the same region by Krahn et al. (2000). Blub-
126 (Helm et al., 2002) (Annex Table 16). Stern and
ber of Alaskan belugas contained PCBs and OC pest-
Addison (1999) analyzed non-ortho PCBs (CBs 77,
icides in ranges similar to those found in belugas from
126, and 169) in beluga from Cumberland Sound. The
the Canadian Arctic (Annex Table 13) (Sang et al.,
TEQ in blubber from 1997 was 6.1 pg/g lw.
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
109
Concentration
Hoekstra et al., 2003a), while levels in Pangnirtung beluga
in beluga blubber,
were consistently on the high end of this range (Stern,
ng/g lw
5000
1999; Stern and Addison, 1999) (Annex Table 13).
4000
Long-finned pilot whales (Globicephala melas)
3000
Screening for OCs was performed on blubber samples
2000
from 420 long-finned pilot whales sampled in 1997 at
the Faroe Islands (Dam and Bloch, 2000). The analyses
1000
were done on pooled samples of whales from nine sepa-
0
rate schools with each school represented by a subsam-
PCBs
DDTs
ple of 50 individuals randomly sampled from a total of
CHLs
805 individuals. In general, concentrations of all OCs
were of similar magnitude in the juveniles and adult
males, but were approximately half as high in adult fe-
males. p,p'-DDE dominated the DDT group, accounting
for 60 ± 6%, 57 ± 7%, and 65 ± 3% of the DDTs in the
young, females and males, respectively. Chlordane was
dominated by trans-nonachlor, which accounted for ap-
proximately 50% of CHLs. There is a general scarcity
of data on these compounds, but it may be noted that in
a study of five male and nine female long-finned pilot
whales stranded in Newfoundland in 1980 (Muir et al.,
1988), concentrations of trans-nonachlor and CHLs
were half of what was found in the Faroese study. The
concentrations of HCB in the Newfoundland study
Figure 4·50. Mean (± 95% CI) concentrations (ng/g lw) of PCBs,
(Muir et al., 1988) were very similar to what was found
DDTs and CHLs in male beluga whale blubber (Stern and Addi-
in the Faroese study (Dam and Bloch, 2000). The much
son, 1999; Krahn et al., 2000; Sang et al., 2000; Andersen et al.,
2001a; Muir and Johansen, 2001; Hobbs et al., 2002b).
higher PCB concentrations found in pilot whales of the
Faroe Islands compared to stranded individuals in New
Further east, Andersen et al. (2001a) and Wolkers
Zealand (Schröder, 1998) is noteworthy, and in agree-
(2002) reported levels and patterns of OC pollutants in
ment with what is seen for baleen whales (OŽShea and
blubber biopsies taken from belugas from western Sval-
Brownell, 1994). In the Faroese study, the mean PCBs
bard (Annex Table 13). Levels reported in the two stud-
for all 417 individuals was 11 900 ng/g ww, whereas the
ies were comparable, and the slightly lower levels in
mean for the 61 individuals from New Zealand was 310
whales examined by Wolkers (2002) were consistent
ng/g ww.
with their younger age (immature) compared with those
In the Faroe Islands, samples from 100 individuals
reported in Andersen et al. (2001a). Andersen et al.
from two pilot whale schools (Sandavágur, August 26,
(2002) also reported high levels of toxaphene (11 400 ±
1997 and Tórshavn, September 24, 1997) were analyzed
4210 ng/g lw) in the same ten Svalbard belugas they ex-
in order to determine the variability in pollutant load
amined for OC pollutants (Annex Table 13). Overall,
within the groups of adult males and females, and juve-
levels of PCBs, DDTs and CHLs in belugas from the
niles (Dam, 2001). No strong relationships between
Arctic are generally highest in the Beaufort and Barents
PCB7 and p,p'-DDE and pilot whale length were found
Seas and western Hudson Bay, somewhat lower in the
although older males tended to have higher concentra-
rest of the Canadian Arctic, and lowest in Cook Inlet,
tions. Toxaphene was also determined in these samples
southern Alaska (Figure 4·50).
including Parlars 26, 32, 50, 62, and 69, but of these, Par-
As is typical of top predators in Arctic marine food
lars 32 and 69 were not detected in any sample. Juvenile
chains (Borgå et al., 2001; Fisk et al., 2001c), the major
males had the highest concentrations of toxaphene and
compounds detected in beluga blubber were PCBs,
levels were lower in adults.
DDTs, toxaphene, and CHLs. OC levels in the Sval-
bard belugas were generally similar to, or slightly higher
Killer whales (Orcinus orca)
than, values in other more westerly Arctic beluga stocks
Killer whale populations that inhabit Washington's
(Annex Table 13) (Muir et al., 1990b; Stern et al., 1994;
Puget Sound (U.S.), the inside waters of British Colum-
Muir et al., 1999b), but were lower than in those from
bia, southeast Alaska, and Kenai Fjords/Prince William
the St. Lawrence River (Canada) (Muir et al., 1990b;
Sound, Alaska, have been extensively studied over the
Muir et al., 1996b). In whales examined by Andersen et
past 30 years. Two eco-types of killer whales, `transient'
al. (2001a), HCHs was dominated by -HCH in con-
and `resident', occur in all of these regions. These eco-
trast to reports for belugas from the Canadian Arctic
types are genetically distinct and differ in various aspects
(Muir et al., 1990b). Patterns in relative prevalence of
of morphology, vocalization patterns, diet, and habitat
various OC compounds to their compound groups were
use. For example, transient killer whales feed on marine
consistent with what is seen in other marine mammals in
mammals, while resident killer whales are fish-eaters.
the Arctic.
Various genetic and photo-identification studies of east-
Toxaphene levels in beluga from Alaska and Sval-
ern North Pacific killer whales have provided informa-
bard were quite variable, with mean values ranging from
tion on the male-female composition of most of these
roughly 1000 to 10 000 ng/g ww (Wade et al., 1997;
resident pods and transient groups, as well as the ap-
110
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
proximate age, reproductive status, and putative recruit-
than in mature porpoises from the more southerly loca-
ment order (birth order) of the individual whales.
tions. The mean TEQ based on PCDD/Fs, non- and
Concentrations of PCBs and OC pesticides, includ-
mono-ortho PCBs was 111 pg/g lw (Annex Table 16).
ing dioxin-like PCB congeners and DDTs, in blubber
biopsies from free-ranging transient killer whales were
Narwhal (Monodon monoceros)
much higher than those found in resident animals sam-
Narwhal are deep-water, benthic feeders and are an im-
pled from the Kenai Fjords/Prince William Sound areas
portant Arctic species that has received little attention
between 1994 and 1999 (Annex Table 13). Mean blub-
in terms of contaminants studies. In the Canadian Arc-
ber PCB concentrations were 3900 ng/g ww in residents
tic, levels of PCBs, DDTs and chlordanes (not corrected
(range 270 - 27 000 ng/g ww) and 59 000 ng/g ww (range
for age) were generally higher in male narwhal from
4900 -140 000 ng/g ww) in transients. These differences
Pond Inlet (northeastern Baffin Island), than those from
are apparently due to the differences in diets of these
Broughton Island (eastern Baffin Island), or Grise Fjord
two killer whale eco-types (Ylitalo et al., 2001). The
(southern Ellesmere Island). Similar trends occurred for
concentrations of PCBs and DDTs that were measured
toxaphene in narwhal from these sites (Stern, 2001)
in blubber of the Alaskan killer whales were much
(Annex Table 13). Concentrations of PCBs, DDTs, and
higher than the concentrations in blubber of various
chlordanes were generally higher in narwhal from Sval-
other cetaceans and pinnipeds that reside and feed in
bard (Wolkers, 2002) as compared to those from Green-
Alaskan waters (Annex Tables 12 and 13) (de March et
land (Denmark, 2002), while HCHs, HCB, and toxa-
al., 1998). The PCB levels measured in these Alaskan
phene levels were comparable between these regions
transient killer whales are similar to those recently re-
(Annex Table 13). Overall, levels of POPs in narwhal
ported in biopsy blubber samples of transient killer
were quite similar in the Canadian Arctic and western
whales from the more contaminated coastal waters of
Greenland, while levels of PCBs, DDTs and chlordanes
British Columbia (Ross et al., 2000). Mean mono-ortho
were considerably higher in the Svalbard narwhal. Lev-
PCB TEQs in residents were 29 pg/g ww (range 1.5-150
els of HCHs, HCB and toxaphene were relatively con-
pg/g), and in transients, 220 pg/g ww (range 14 -580
sistent across the sites sampled.
pg/g) in blubber (Annex Table 16).
Organotins in cetaceans
Harbour porpoises
Studies indicate that marine mammals are exposed to
Concentrations of PCBs, HCB, p,p'-DDD, p,p'-DDE, -
organotins but data from the Arctic area are lacking.
HCH, and PCDD/Fs were lower in immature harbour
Harbour porpoise, harbour seal, and ringed seal are
porpoises from southwestern Greenland in comparison
species that have been analyzed for organotins in Nor-
with levels in immature, non-Arctic dwelling porpoises
wegian territories (Berge et al., 2002). Relatively high
from the North and Baltic Seas (Bruhn et al., 1999). -
concentrations were observed in liver from harbour por-
HCH values were highest in porpoises from southwest-
poises caught in 1988 (Table 4 · 8), just before restric-
ern Greenland. p,p'-DDT was only detected in the Green-
tions on the use of TBT (mainly on small boats) were
land porpoises, possibly due to a higher degree of meta-
introduced in several other European countries. The
bolic induction in the non-Arctic animals. The higher
concentrations were significantly reduced 11 years later
proportion of lower chlorinated PCBs in the Arctic sam-
(Table 4 · 8), possibly as a consequence of the introduced
ples is likely associated with a predominance of these
restrictions. Mean concentrations in porpoise from the
more volatile compounds in the atmosphere, or perhaps
west coast of Norway in 1998/1999 were higher than in
to a lesser degree, metabolic induction, and subsequent
samples collected further north in the Barents Sea. Con-
excretion of these compounds, relative to the non-Arctic
siderably lower concentrations were observed in seals
animals. The concentrations of PCDD/Fs, given as TEQs
compared to porpoises. The lowest concentrations were
in the Arctic porpoises, ranged from 0.2 to 0.9 pg/g lw
found in seals from Spitsbergen, where only traces of
with a median of 0.41 pg/g lw (Annex Table 16). Mono-
DBT and MBT (degradation products of TBT) were
ortho PCBs were also determined, and TEQs based on
found. The degradation products in all samples were
these were stated to be 40-70 times higher than for
generally more predominant than TBT itself, and proba-
PCDD/F TEQs in the three populations, but actual TEQ
bly indicated metabolic capacity to degrade TBT. Triph-
values were not given in the publication. CB 118 con-
enyltin (TPhT) was observed in all porpoise samples and
tributed most to the total TEQs.
in common seals but not in ringed seals. The limited
Further east, Berggren et al. (1999) found that PCB
data available indicate low to moderate exposure to or-
and DDT levels in blubber sampled from mature male
ganotins in Arctic areas like Spitsbergen and Bjørnøya.
harbour porpoises from the Norwegian west coast were
Marine mammals are more exposed, however, along the
relatively high compared to other Arctic-dwelling ceta-
Norwegian coast. It is anticipated that exposure will de-
ceans, and were comparable to levels in samples taken
cline further as a consequence of additional restrictions
from the Baltic and Kattegat-Skagerak Seas (Annex
on the use of organotin in antifouling paint for ships.
Table 13). They were an order of magnitude higher than
Butyltin levels were quantified in liver tissue from
in porpoises from southwestern Greenland (Bruhn et al.,
male Dall's porpoises sampled from the Aleutian Islands
1999). Porpoises from the west coast of Norway had the
chain, the Bering Sea, and the northwestern North Pa-
most variability in non-ortho PCB concentrations (96-
cific between 1979 and 1984 (Tanabe et al., 1998). Low
7624 pg/g lw) compared to the other more southerly
levels (BTs = 41-180 ng/g ww) were found in Dall's por-
sites, which may be caused by exposure of some por-
poises from these sites, compared with cetaceans and
poises to a local contaminant source. Their PCDD/F
pinnipeds examined in other regions, including Japan,
concentrations ranged from 7.3 to 19 pg/g lw, lower
China, the Philippines, the west Pacific and India (17-
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
111
Table 4 · 8. Concentrations of mono-, di- and tributyltin and triphenyltin (in ng Sn/g ww) in marine mammals and seabirds from Norway and
the Faroe Islands.
Species/year
Location
dw %
MBT
DBT
TBT
TPhT
Reference a
Harbour porpoise, 1988
Norwegian coast of the Barents Sea
35
285
98
27
1
Harbour porpoise 1999
Norwegian coast of the Barents Sea
11
67
34
6
1
Harbour porpoise, 1999
West coast of Norway
19
122
40
10
1
Common seal ,1998/1999
West coast of Norway
11.7
8.6
1.2
3.3
1
Ringed seal, 2000
Spitsbergen (Ny-Ålesund)
1
1.6
< 1
< 1
1
Glaucous gull, 1998
Bjørnøya
< 1
11.7
< 3
< 3
1
Pilot whale, adult male, 2000
Faroe Islands
36
< 0.1
1.3
3.0
< 0.1
2
Pilot whale, adult female, 2000
Faroe Islands
22
< 0.1
1.4
1.8
< 0.1
2
Pilot whale, adult female, 2000
Faroe Islands
29
< 0.1
1.8
2.2
< 0.1
2
Pilot whale, fetus, 2000
Faroe Islands
19
< 0.1
1.8
1.2
< 0.1
2
Pilot whale, fetus, 2000
Faroe Islands
21
< 0.1
< 0.1
< 0.1
< 0.1
2
Pilot whale, fetus, 2000
Faroe Islands
14
< 0.1
< 0.1
< 0.1
< 0.1
2
a 1: Berge et al. (2002); 2: Mikkelsen (2002).
3000 ng/g ww). DBTs were predominant among the bu-
DDTs. However, PBDEs consist of a much smaller num-
tyltins. MBT, DBT and TBT concentrations in the Dall's
ber of individual compounds, so the difference between
porpoises ranged from 22 to 33, 29 to 59, and 12 to 26
individual PBDE and individual PCB congeners is less.
ng/g ww, respectively. Further east, butyltin (MBT, DBT,
BDE47 is the most common congener measured, fol-
and TBT) was not detectable in livers from five Hudson
lowed by BDE congeners 99 and 153. Other BDE con-
Strait (Canada) belugas sampled in the summer of 1998
geners, such as 100 and 49 have been measured in Cana-
(de Mora et al., 1999). The authors concluded that the
dian Arctic beluga (Stern and Ikonomou, 2000; 2001),
limited maritime shipping activities in northern Quebec
but others, such as BDEs 85 and 138, have been re-
were not sufficient to provide an appreciable input of
ported as non-detectable in Svalbard beluga and Faroe
TBT into the marine environment of northern Quebec,
Islands pilot whales (van Bavel et al., 2001). These con-
and that since these same whales were contaminated
geners are found at lower concentrations in the technical
with OCs but not butyltins, it was unlikely that aerial
PBDE products, but may also be less prevalent due to
input could be a source of organotin compounds to Arc-
biotransformation.
tic whale populations. In contrast to this, butyltins were
Although it is too early to draw conclusions about
detected in all 21 samples examined from the more south-
spatial trends of PBDEs in Arctic marine mammals,
erly St. Lawrence River population of beluga whales lo-
there are sufficient data to suggest that concentrations
cated in eastern Canada (de Mora et al., 1999).
are higher in the European Arctic compared with the
Organotins, such as mono-, di- and tri-substituted
North American Arctic. Concentrations of PBDEs were
butyl- and phenyltin compounds, were analyzed in pilot
92.9 ± 56.5 ng/g ww in Svalbard beluga blubber col-
whale kidney and blubber from three adults (two fe-
lected in 1998 (van Bavel et al., 2001) and were higher,
males, one male) and three fetuses sampled in the Faroe
compared to concentrations of 15.5 ng/g ww in beluga
Islands in 2000 (Mikkelsen, 2002). The results showed
from the western Canadian Arctic (Stern and Ikomonou,
no detectable concentrations of organotins in blubber
2000; 2001). PBDE concentrations in the blubber of
tissue and kidney (detection limit 0.1 ng Sn/g ww) ex-
ringed seals from northeastern Greenland (58 ± 23 ng/g
cept some low concentrations of DBT and TBT near the
ww) were an order of magnitude higher than levels re-
detection limit in the adults and in one of the fetuses
ported from western Greenland (3.6 ± 1.1 ng/g ww)
(Table 4 · 8).
(Muir and Johansen, 2001) and the western Canadian
Arctic (4.6 ng/g, ww) (Ikonomou et al., 2002).
Minke whales from the Barents Sea had PBDE lev-
4.4.6.3. `New' chemicals in pinnipeds and cetaceans
els of 0.15 - 0.45 ng/g ww in muscle, while minke whales
Of the data produced on `new' chemicals in the Arctic,
from the Norwegian Sea had higher levels at 3.1-15 ng/g
the greatest amount has been generated for marine
ww in muscle (Herzke, 2002b).
mammals, in particular seals and whales. These are logi-
The greatest concentrations of PBDEs measured in
cal animals in which to check for `new' chemicals, as
the Arctic are those observed in Faroe Islands long-fin-
seals and whales have among the highest levels of OCs
ned pilot whales (144 -1620 ng/g ww) (Annex Table 17)
in the Arctic.
(van Bavel et al., 2001). Concentrations are an order of
magnitude greater than in any other Arctic marine mam-
PBDEs
mal examined to date. Due to a general lack of PBDE
PBDE data have been produced for seals and whales
data in the Arctic, it is difficult to determine if these high
from the Canadian and European Arctic (Annex Table
levels are due to spatial trends or the behavior of the
17). There have been two temporal trends studies of
pilot whales (i.e. trophic level). Additionally, as in belu-
PBDEs, in beluga (Stern and Ikonomou, 2000; 2001)
ga whales from Svalbard (van Bavel et al., 2001), sur-
and ringed seals (Ikonomou et al., 2002), which have
prisingly high levels of methoxylated PBDE (Me-O-
shown that the concentrations of these compounds are
PBDE), almost comparable to the most abundant BDE47,
increasing in Arctic marine mammals (see Section
were found in the pilot whale. Results for long-finned
5.4.6.1). In general, concentrations of PBDEs are orders
pilot whales from Tórshavn, Faroe Islands, also revealed
of magnitude less than legacy OCs such as PCBs and
large differences between PBDE concentrations with age
112
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
PBDE concentration in pilot whale blubber, ng/g lw
Lower chlorinated CBz have been detected in Arctic
1400
seawater and in lower trophic organisms from northern
Quebec (Muir et al., 2000c; Muir et al., 2000f).
1200
Hexachlorobutadiene (HCBD) is mainly created as a
by-product in the manufacture of chlorinated hydrocar-
1000
bons like tri- and tetrachloroethene. This hydrophobic
(log Kow 4.78) and volatile product (vapor pressure =
800
19.96 -20.00 Pa (20 -25°C)) (Mackay et al., 2000) has
been detected at low levels in Arctic biota (Muir et al.,
600
2000f) and in the north Atlantic Ocean (WHO/IPCS,
400
1994).
TCPM-OH was measured in five ringed seals from
200
northern Russia, near the Yenisey River, and had a mean
concentration of about 47 ng/g lw, in 1995 (Watanabe et
0
al., 1999).
Adult
Adult
Juvenile
Juvenile
males
females
males
females
Blubber from beluga whales collected in 1994 near
Kimmirut, Nunavut, was analyzed for PCNs and non-
Figure 4 · 51. Mean (and range) of concentrations of PBDEs in long-
and mono-ortho PCBs (Helm et al., 2002). PCN con-
finned pilot whales (adult males and females compared to juvenile
centrations ranged from 40 to 384 pg/g (n = 6), on a wet
males and females) caught at the Faroe Islands (van Bavel et al.,
2001).
weight basis (approximately 90% lipid), and were dom-
inated by PeCNs. PCN levels were lower in female be-
and sex (van Bavel et al., 1999). However, the highest
lugas (n = 3) than in males (n = 3). Total non- and mono-
levels were found in juveniles (402-1246 ng/g lw), with
ortho PCB concentrations were much higher than
somewhat lower values in adult males (397-669 ng/g lw)
PCNs, ranging from 14.4-294 ng/g ww in beluga
and the lowest values in adult females (126-326 ng/g lw)
whale blubber with the CBs 118, 105, and 156 having
(Figure 4·51) (van Bavel et al., 1999). This indicates
the highest concentrations. PCNs contributed an extra
transfer of the PBDEs from mother to calf by lactation.
11% (0.026 - 0.40 pg TEQ/g ww) to total TEQs (0.30-
Results from a mother and fetus also indicated the pres-
2.6 pg TEQ/g ww) calculated using non- and mono-
ence of a partial transplacental barrier, as the level in the
ortho PCBs and PCNs. Most of the TEQs in beluga were
fetus was generally half the amount of the mother (van
accounted for by CB 126.
Bavel et al., 2001).
Blubber from ringed seals from Pangnirtung, Nuna-
vut, collected in 1993 also contained PCNs (Helm et al.,
Other `new' chemicals
2002), but concentrations were lower than in beluga,
In addition to the PBDEs, a number of studies have
ranging from 29 - 63 pg/g ww. The PCNs added insignif-
also examined several other `new' OCs, including PFOS,
icantly to the total TEQs.
tris(4-chlorophenyl) methanol (TCPM-OH), SCCPs,
Endosulfan sulfate was found in blubber of beluga
PCNs, endosulfan sulfate, and a number of chiral com-
from Pangnirtung collected in 1996/1997, with approxi-
pounds.
mate mean concentrations of 13.5 ng/g lw (Stern and
PFOS was detected in the blood of ringed seals, and
Addison, 1999).
blood and liver of northern fur seals (Table 4 · 9) (Giesy
and Kannan, 2001; Kannan et al., 2001a). Concentra-
Chiral contaminants
tions were greater in liver compared to blood. No obvi-
As discussed in the seabird section (Section 4.4.5.1), chi-
ous trends between the Canadian and European Arctic
ral pollutants exist in two forms as optical isomers
in PFOS in ringed seals were observed, although this is a
called enantiomers. Enantiomers have identical physical-
very small dataset.
chemical properties and abiotic degradation rates, but can
Table 4 · 9. Concentrations of PFOS in liver and/or blood of Arctic marine mammals (ng/g ww or ng/mL) from Kannan et al. (2001a) and
Giesy and Kannan (2001).
Species/tissue
Location
n
Collection year
Sex
Age class
PFOS a
Ringed seal blood plasma
Cumberland Sound
24
1998
M and F
< 3 -12
Ringed seal blood plasma
Spitsbergen
10
1996
4 M; 6 F
3.0 -20 yr
8.1 ± 2.5
Ringed seal blood plasma
Spitsbergen
8
1998
3 M; 5 F
2.0 -12 yr
10.1 ± 2.7
Northern fur seal liver
Pribilof Islands (Bering Sea)
13
1995 and 1998
11 M; 2 F
3 pups (< 4 m);
<10-122 [38]
10 subadults
(2-4 yr)
Northern fur seal blood
Pribilof Islands (Bering Sea)
10
1995
10 F
adult (> 3 yr)
< 6
Northern fur seal blood
Pribilof Islands (Bering Sea)
7
1995
7 M
subadult (2 - 4 yr)
< 6
Polar bear liver
Northwestern Alaska
17
13 Dec. 1997-
14 M; 3 F
13 adults (> 5 yr);
175- 678 (350)
(Barrow; Nuiqsut; Point Lay;
15 Jun. 1999
4 subadults (3- 4 yr)
Gambell; Shishmaref;
Little Diomede; Savoonga)
Polar bear blood
Beaufort Sea
14
1999
7 M; 7 F
n.a.
26 - 52 (34)
a Values in brackets [ ] indicate the percentage of detectable observations. Values in parentheses ( ) indicate the mean.
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
113
have different rates of biotransformation, providing in-
bolize -HCH efficiently (Moisey et al., 2001). EF val-
formation on the ability of species to biotransform OCs.
ues in the ringed seals varied considerably from other
Wiberg et al. (2000) examined ERs of -HCH and
Arctic marine mammals and seabirds, providing addi-
several chlordane compounds in the blubber and liver of
tional evidence that the type(s) and characteristic(s) of
ringed seals from Resolute Bay in the Canadian Arctic.
the enzymes involved in biotransformation of chiral
The ERs in ringed seals were frequently nonracemic (ER
OCs vary between these organisms.
1), due to enantiomer-specific biotransformation; how-
ever, cod from the same region showed near-racemic
4.4.6.4. Persistent OCs
mixtures (ER =1) for most compounds. (+)- -HCH was
in other pinniped and cetacean tissues
more abundant than ()- -HCH in ringed seals. There
was no uniform trend for the ER changes in the various
Compared to blubber, fewer analyses of brain, liver, kid-
chlordane compounds examined. It was also determined
ney, muscle, and blood have been made in pinnipeds and
that oxychlordane was formed in ringed seals and me-
cetaceans. However, in all these tissues, OC concentra-
tabolized by polar bears that preyed on them, and the
tions are generally lower than in blubber because of
ER had an important role in the class separation of
their lower lipid content. Low ng/g ww levels of PCBs
male/female seals and fat/liver tissues.
and OC pesticides were found in liver, kidney, and mus-
EFs of -HCH and other chiral contaminants in seal
cle from ringed seals sampled from Greenland (Muir
blubber may not reflect the metabolic capability of seals.
and Johansen, 2001) and in blood sampled from ringed
Wiberg et al. (1998; 2000) noted near racemic -HCH
and bearded seals from Svalbard, Norway, and Alaskan
(EFs = approximately 0.52) in blubber of ringed seals
northern fur seals (Bang et al., 2001; Beckmen, 2002)
but non-racemic values in liver (EFs = approximately 0.6).
(Annex Table 12). Similarly, low ng/g ww levels of PCBs
This phenomenon was observed with other chiral pollu-
and OC pesticides were found in brain, liver, and muscle
tants, such as trans-chlordane, but in some cases, the EF
from beluga from Hendrickson Island in the western
was greater in blubber (Wiberg et al., 2000). Wiberg et
Canadian Arctic (Metcalfe et al., 1999) and in bowhead
al. (1998) attributed this difference to greater metabolic
whales from the Bering-Chukchi-Beaufort Seas (Hoek-
activity in the liver as compared to the blubber. This
stra et al., 2002c) (Annex Table 13). When lipid concen-
would imply that the proportion of the -HCH body
trations were compared to wet weight concentrations of
burden that is transformed is small, and consequently,
OCs in brain, liver, kidney, and muscle from grey whales
the EF in ringed seal blubber is closer to that in the diet
sampled from the Chirikov Basin of the Russian Bering
than in the liver. This is not always the case, since EFs of
Sea, lipid levels were significantly correlated to PCBs,
many chiral OCs in ringed seal blubber have been found
DDTs, CHLs, and HCB (Krahn et al., 2001; Tilbury
that do not match their main prey item, Arctic cod
et al., 2002). This relationship is consistent with a study
(Wiberg et al., 2000; Moisey et al., 2001). In seabirds,
by Aguilar and Borrell (1985) reporting that lipid con-
which do not retain as large a reserve of fat as found in
tent is an important factor in controlling accumulation
ringed seals, there were no differences in EFs of chiral
of lipophilic OCs in marine mammals. In both beluga
chlordanes between liver and fat (Fisk et al., 2001b).
and grey whales, concentrations of OCs in these tissues,
Differences in EFs of chiral pollutants between tissues of
with the exception of brain, were generally more compa-
seals, and potentially other marine mammals, require
rable when the values were calculated on a lipid weight
further study.
rather than on a wet weight basis (Krahn et al., 2001;
Harbour and grey seals from Iceland showed an -
Tilbury et al., 2002).
HCH ER > 1 (Klobes et al., 1998a). The ER of CB149
In brain tissue, total lipid-normalized concentrations
was comparable in the two species, but for oxychlor-
were significantly lower than in all other tissues. This is
dane, ER < 1 was observed in harbour seals, while the
in agreement with previous reports that the bloodbrain
oxychlordane ER in grey seals was >1. The differing ER
barrier controls the transport of certain contaminants to
for oxychlordane was consistent with results for blubber
brain tissue (Norton, 1980). Beluga brain samples could
from two harbour seals from the German North Sea
be distinguished from other tissues by differences in PCB
coast (König et al., 1994) and a Baltic Sea grey seal
congener patterns and higher concentrations of HCHs
(Müller and Buser, 1994). An excess of (+) -HCH (EFs
(primarily -HCH), as was reported in an earlier study
= 0.58) was found in the blubber of harbour and grey
for northern fur seals and harbour porpoises (Mössner
seals, although no data were provided for their food.
et al., 1992). In addition, the lipids in the brain of ma-
EFs of chiral contaminants and stable isotopes of ni-
rine mammals consist of high proportions of polar lipids
trogen ( 15N) and carbon ( 13C) were measured along
(i.e. phospholipids and cholesterol) (Fukushima and
with OCs in ringed seals collected from the east and
Kawai, 1980; Aguilar and Borrell, 1985; Tilbury et al.,
west side of the Northwater Polynya in northern Baffin
1997) that have a lower affinity for OCs than neutral
Bay (Fisk et al., 2002d). Cis- and trans-chlordane, oxy-
lipids. Thus, the greater proportion of neutral lipids (i.e.
chlordane, and heptachlor epoxide were all non-racemic
triglycerides and non-esterified fatty acids) found in tis-
in the ringed seal blubber but did not vary with age, sex
sues other than the brain favors the accumulation of OC
or collection site. -HCH appeared racemic (EF = 0.50 ±
compounds in these tissues (Kawai et al., 1988). These
0.01) in the seals, although this EF is different from
variations in patterns of POPs in the different tissues
those previously observed in their prey species, and was
may also be influenced by differences in contaminant
found to vary significantly with age. An overall food
metabolism or the degree of blood perfusion in the vari-
web assessment of -HCH in the Northwater Polynya,
ous tissues (Kiceniuk et al., 1997; Jenssen et al., 1996;
which included the ringed seal data of the study by Fisk
Metcalfe et al., 1999). The need for caution in interpret-
et al. (2002d), concluded that ringed seals do not meta-
ing OC concentration data from different tissues is
114
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
further demonstrated by findings reported for a study
Concentration in bowhead whale blubber, ng/g lw
examining how concentrations of OCs in blood and
1400
Toxaphene
blubber vary with nutritional condition in captive and
1200
wild, fasting ringed seals (Lydersen et al., 2002). The
1000
Males
Females
study demonstrated that extreme variability occurs in
800
the concentrations of OCs in seal blood in response to
600
change in body condition as a result of fasting, and that
400
the responses of blubber OC concentrations are also
200
very different compared to those in blood. The authors
0
concluded by recommending that, since the natural
1400
variation in body condition is extreme during annual
CHLs
1200
cycles of phocid seals, blood should not be used in
Males
1000
Females
studies of OCs, where the aim of the study is to moni-
800
tor OC levels for comparative purposes or time-trend
600
analyses.
400
200
4.4.6.5. Effects of age and sex
0
on OC levels in pinnipeds and cetaceans
1400
PCBs
1200
As mentioned previously, age and sex are important fac-
Males
1000
tors that must be taken into account to ensure accurate
Females
800
comparisons of contaminant levels in pinnipeds and
600
cetaceans. Results of recent studies are consistent with
400
previously recorded trends showing that most OCs
200
occur at lower levels in juveniles than adults, and lower
0
in adult females than in adult males (Krahn et al., 1997;
1400
Wade et al., 1997; Kleivane and Skaare, 1998; Severin-
DDTs
1200
sen et al., 2000; Bang et al., 2001; Ylitalo et al., 2001;
Males
1000
Fisk et al. 2002d; Hoekstra et al., 2002c; Krahn et al.,
Females
800
2001). PCB and OC pesticide concentrations also in-
600
crease with age in males, and may either decrease, re-
main relatively constant or increase with age in females,
400
although in the latter case, generally at a slower rate
200
than in males (Wolkers et al., 1998b; Muir et al., 2000b;
0 6
8
10
12
14
16
Fisk et al., 2002d; Hoekstra et al., 2002c). Lower levels
Body length, m
of contaminants in females are normally primarily at-
Figure 4·52. Body length versus OC concentrations in blubber
tributable to the transfer of compounds to offspring dur-
samples from male and female bowhead whales. Significant rela-
ing gestation and lactation. Whether or not females ex-
tionships between increasing body length and OC concentrations
perience age-related changes in contaminant levels is
(p < 0.05 for all comparisons) were found for male bowhead whales
variable, and regardless of the rate of change, this age
(Toxaphene, r2 = 0.44; CHLs, r2 = 0.38; PCBs, r2 = 0.56; DDTs,
r2 = 0.45). Source: Hoekstra et al., 2002c.
concentration relationship likely depends largely on their
level of contaminant exposure, as well as how often they
found no difference in PCB congener pattern, relative to
successfully produce and wean offspring. Nonetheless, it
CB153, between the sexes in adults, while juveniles
is important to remember that age- and sex-related trends
showed significantly higher relative concentrations of
in contaminant concentrations may vary both within
the lower chlorinated PCBs (28, 52, 74, 99, 101, and
and between species, depending on the compound being
118) and lower relative concentrations of the higher
examined.
chlorinated PCBs (170 and 180) as compared to the
Concentrations of PCBs, DDTs, and CHL com-
adults (Wolkers et al., 1998b).
pounds often increase with age in marine mammals.
In male Alaskan bowhead whales, levels of PCBs,
This was the case in both sexes of ringed seals from the
DDTs, CHLs, and toxaphene significantly increased
northern Baffin Bay region (Fisk et al., 2002d), and in
with body length, and thus presumably with age (Figure
male, but not female, ringed seals from Alaska (Kucklick
4 ·52) (Hoekstra et al., 2002c). In female bowheads, this
and Krahn, 2002), as well as those in a circumpolar
relationship applied until they reached approximately
study that statistically examined ringed seal data from
13 m in length, while those longer than 13 m had gener-
the previous AMAP assessment (Muir et al., 2000b).
ally lower concentrations of these compounds than
The significant relationships observed in the female
shorter, younger females. Similar decreasing OC concen-
ringed seals from northern Baffin Bay are likely due to
trations with age occurred in female belugas from Point
the inclusion of very old female seals (> 40 years) that
Lay, Alaska (Wade et al., 1997). However, in contrast to
have probably stopped reproducing (Fisk et al., 2002d).
this, concentrations of HCHs and HCB or CBz often
Wolkers et al. (1998b) found PCBs increased with age in
do not show sex- or age-related differences in pinnipeds
Svalbard ringed seals, but that sex was not an important
and cetaceans. For example, no sex-related differences
variable, and suggested that in the Svalbard seals, con-
were observed for HCB or dieldrin concentrations in
tinued feeding by females during lactation may compen-
Alaskan ringed seals of comparable ages (Kucklick and
sate for loss of OCs during lactation. The authors also
Krahn, 2002), or for CBz and HCHs in seals from the
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
115
Nunavut region (Fisk et al., 2002d). Similarly, HCH
mean value for sum toxaphene for the adult female
and CBz or HCB levels were independent of age and
white-sided dolphins was only one tenth that of the ju-
sex in Alaskan bowhead whales and Barents Sea minke
veniles (Parlar 50 at 1872 ng/g lw, n = 7 juveniles).
whales (Kleivane and Skaare, 1998; O'Hara et al., 1999;
Hoekstra et al., 2002c). Notably, much lower levels of
4.4.7. Polar bear
OCs occurred in reproductive female Alaskan killer
whales than sexually immature whales or mature male
Polar bears (Ursus maritimus) are widely distributed
animals of the same age class (Ylitalo et al., 2001), and a
throughout the Arctic, including some subarctic regions,
single beluga fetus from Point Lay, Alaska, had about
and range over large areas in search of food. They move
10% higher concentrations for all OCs compared to its
south with the ice in the autumn and winter and then
mother (Wade et al., 1997).
north as the pack ice melts in the spring and summer.
Recruitment order (birth order) can also influence
These seasonal movements of the sea ice also influence
the concentrations of OCs in pinnipeds and cetaceans.
the distribution and concentration of their primary prey,
For example, in northern fur seals from St. George Is-
ringed and bearded seals (Stirling et al., 1982; Kingsley
land, Alaska, pups of young (presumably primiparous)
et al., 1985). Polar bears are top Arctic predators, and
dams had significantly elevated levels of PCBs in their
often eat only the blubber from a seal (Stirling and McE-
blood as compared with pups of older (multiparous)
wan, 1975), where the highest concentrations of OCs
dams (Beckmen et al., 1999). Similarly, in adult male
are found. Polar bears have superior biotransformation
resident Alaskan killer whales, first-recruit whales con-
capacity and have high levels of OC metabolites.
tained much higher OC concentrations than those meas-
OC levels in polar bears were covered extensively in
ured in non-first-recruited (e.g., second-recruited, third-
the previous AMAP assessment (de March et al., 1998)
recruited) resident animals from the same age group (Yl-
with good spatial coverage. Much like other marine
italo et al., 2001).
mammals, OCs in polar bears were found to be gener-
ally highest in the European and lower in the North
Faroe Islands study
American Arctic (de March et al., 1998). Some spatial
A recent study in the Faroe Islands examined the rela-
trends were also observed within the Canadian Arctic
tionship between OC concentrations and length in pilot
(Norstrom et al., 1998).
whales (1997), white-sided dolphins (Lagenorhynchus
Since the first AMAP assessment, monitoring of OCs
acutus) (1997), and grey seals (1993-1995) (Dam,
in polar bears has continued in western Hudson Bay
2001). The following comparisons of the OC concentra-
(Norstrom 2000; 2001), Alaska, Svalbard, and Green-
tions in the three species are based on females because
land. There have also been studies on OC levels in polar
they maintain constant OC concentrations that are not
bear plasma from the Russian Arctic (Andersen et al.,
dependent on age, and because there were a greater
2001b; Lie et al., 2003). Temporal-trend studies have
number of females to sample, especially in pilot whale
been carried out in western Hudson Bay and Svalbard
pods. Overall, the single OC occurring at the highest
polar bears and are discussed in detail in Section 5.4.5.2.
concentration was p,p'-DDE, which was found at
10 800 ng/g lw in the juvenile females of one pod of pilot
Alaska polar bears
whales, with decreasing concentrations among juveniles
Although elevated OC concentrations have been docu-
in the other pilot whale pod, followed by white-sided
mented in Canadian, eastern Greenland and Norwegian
dolphins and grey seals. The OCs occurring in the next
polar bear populations, relatively little information is
highest concentration were Parlar 50 (a component of
available for populations in Alaska. Lentfer (1976) doc-
toxaphene) at 3900 ng/g lw and CB 153 at 3600 ng/g lw
umented elevated OC concentrations in polar bears
in the same group of juvenile pilot whales that had the
prior to the major oil and gas development on the North
highest p,p'-DDE concentrations. p,p'-DDT and trans-
Slope. Data collected through satellite telemetry indicate
nonachlor were both found at similar concentrations in
that there are two distinct polar bear population stocks
the odontocete juveniles, but were markedly lower in
in Alaska: one in the southern Beaufort Sea and the
grey seals.
other in the Chukchi/Bering Seas (Amstrup, 1995), with
When comparing the juvenile and adult female grey
an area of overlap from Point Barrow to Point Hope.
seals, white-sided dolphins, and pilot whales, it ap-
Differences in the feeding ecology of polar bears be-
peared that the difference in OC burden between the
tween the Beaufort and the Chukchi/Bering Seas may af-
two age groups was highest for white-sided dolphins
fect OC concentrations found in the two stocks. Specifi-
and lowest for grey seals. This could be a consequence of
cally, polar bears in the Chukchi/Bering Seas feed more
different criteria used to sort individuals into the age
heavily on Pacific walrus carcasses.
groups for each species. Only grey seals were sorted
Levels of PCB, DDT, CHL, and HCH deter-
based on actual inspection of reproductive state, and the
mined in adult male polar bears sampled from the Bar-
odontocetes were sorted according to body length. The
row and St. Lawrence Island regions of Alaska between
difference between PCBs in the juvenile and adult
1996 and 1998 (Krahn et al., 2002), were consistent
white-sided dolphins was less than the average seen for
with levels in adult males from the southern Beaufort
the other OCs. Some of the chlordanes and -HCH
Sea population in northern Alaska and the Chukchi/
exhibited a similar pattern. This generally occurred for
Bering Sea population in western Alaska (Evans, 2001)
the two other species. The OC with greatest difference
around the same time (Annex Table 14). These data pro-
amongst the two age groups was oxychlordane, which
vide an important addition to contaminant level data in
occurred at an exceptionally low concentration (27 ng/g
Alaska. Levels of PCBs in these Alaskan bears are rela-
lw) in adult female white-sided dolphins. Similarly, the
tively low compared to levels found in polar bears in
116
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Concentration in polar bear,
other polar bears, PCBs dominated the OC loads with
ng/g lw
concentrations that were an order of magnitude greater
40 000
8000
500
than any other OC group. Concentrations of OCs were
400
greater in the males except for chlordanes, which have
30 000
6000
been observed in polar bears from other regions (Nor-
300
strom et al. 1998). Concentrations of
20 000
4000
PCBs were much
200
lower than previously reported for East Greenland bears
whilst levels of DDE were within the range previously
10 000
2000
100
reported (see Section 5.4.5).
0
0
0
PCB, fat
Iceland polar bears
PCB, blood
Although polar bears are not naturally occurring in Ice-
HCH, fat
HCH, blood
land, they do appear occasionally on drifting pack ice.
Klobes et al. (1998b) analyzed PCB and OC pesticide
levels in the adipose tissue and liver of one such polar
bear. They found distinctly different contaminant pro-
files in the two tissues, where the liver had patterns sim-
ilar to those found in the Icelandic Arctic fox, with oxy-
chlordane as the predominant compound. In the adipose
tissue, CB 153 predominated, followed by C180 and
oxychlordane. Oxychlordane and p,p'-DDD were the only
compounds found to be more abundant in liver than in
adipose tissue, and toxaphene Parlars 26 and 50 were
present in the adipose, but not the liver tissue. The sum
concentration of Parlars 26 and 50 found in adipose tis-
sue was within the range of the levels of toxaphene Par-
Figure 4 ·53. Concentrations (of PCBs and HCHs in blood from
lars (26, 52, and 62) quantified in the adipose tissue of
adult female polar bears (age 5 - 28 yr) from Svalbard and the Russ-
polar bears from Svalbard in an earlier study (Bernhoft
ian Arctic (Andersen et al. 2001b), and in fat from polar bears (ad-
et al., 1997). Due to the high levels of oxychlordane rel-
justed to levels expected in 11-year-old males after correction for
age and sex) from the Bering Sea, Canada, eastern Greenland, and
ative to PCBs, the authors concluded that it was likely
Svalbard (de March et al., 1998). At Svalbard, lipid-weight PCB
that the bear originated from Greenland, not Svalbard.
concentrations measured in fat are approximately five times higher
than in blood from the same animals. Assuming that this relation-
OCs in Norwegian and Russian polar bear plasma
ship is the same in other areas, high fat PCB concentrations can be
Geographical variations in PCB (Andersen et al., 2001b)
expected in bears in the Russian Arctic.
and OC pesticide concentrations (Lie et al., 2003) were
eastern Hudson Bay, Canada, eastern Greenland, and
studied in blood samples from ninety adult female polar
Svalbard, Norway (Figure 4 ·53). PCB levels for males
bears from Svalbard, Franz Josef Land, Kara Sea, East
from Alaska were higher than those reported by Nor-
Siberian Sea and Chukchi Sea, between 1987 and 1995
strom et al. (1998) for three bears taken west of Barrow,
(Annex Table 14). Regional differences in levels and pat-
Alaska. Significantly higher levels of PCBs were found
terns of PCBs, oxychlordane, trans-nonachlor, -HCH,
in bears from the southern Beaufort Sea population than
-HCH, and p,p'-DDE were found. Bears from Franz
in the Chukchi/Bering Seas population. Average HCH
Josef Land and the Kara Sea had similar PCB levels and
levels in bears sampled by Evans (2001) (Annex Table
these were higher than all other populations (Figure 4 ·53).
14) are among the highest levels reported in the Arctic,
Svalbard polar bear PCB levels were similar to those from
and were similar to the high levels reported for the
the East Siberian Sea, but higher than those from the Chuk-
Chukchi and Bering Seas by Norstrom et al. (1998).
chi Sea. Svalbard polar bears had relatively lower propor-
There were no significant differences between HCH
tions of CB99 and higher proportions of CB194 than
levels in the Chukchi/Bering Seas and southern Beaufort
bears from other regions. Bears from Franz Josef Land
Sea populations. -HCH, the most persistent HCH iso-
had higher proportions of CB180, but lower CB153 lev-
mer, constituted about 93% of HCHs. Although -
els compared to all other regions. Of the PCB congeners
HCH contributed only a small fraction of the HCHs in
investigated by Andersen et al. (2001b), the lower chlori-
fat, unlike -HCH, it occurred in significantly greater
nated CBs increased, and the higher chlorinated CBs de-
concentrations in bears from the southern Beaufort Sea
creased from Svalbard eastward to the Chukchi Sea. In all
region. The chlordane compounds in these bears were
regions, oxychlordane was the dominant OC pesticide,
the next most abundant compounds, and although, the
and the highest levels of oxychlordane, trans-nonachlor,
levels were not significantly different between the two
and DDE were found in bears from Franz Josef Land and
populations (p < 0.07), there was a trend suggesting
the Kara Sea. Polar bears from the Chukchi Sea had the
higher levels in the southern Beaufort Sea population.
highest levels of - and -HCH. The lowest -HCH con-
centration was found in bears from the Kara Sea and was
Greenland polar bears
lower than in bears from all the other circumpolar re-
OC levels were recently determined in the fat of Green-
gions. In all the bears, HCHs was dominated by -
land polar bears collected in 1999/2000 (Sonne-Hansen,
HCH. HCB levels did not differ between regions.
2002; Dietz et al., 2003) (Annex Table 14). These bears
Results from Andersen et al. (2001b) and Lie et al.
ranged in age from two to ten years. As observed in
(2003) combined with earlier findings (Bernhoft et al.,
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
117
1997; Norstrom et al., 1998), indicate that polar bears
tween males and females in 1995. Males had 30% lower
from Franz Josef Land and the Kara Sea have the highest
levels of chlordanes than females, which is the same as
PCB, CHL and DDT levels in the Arctic. Decreasing
that found by Norstrom et al. (1998). Polischuk et al.
trends were seen eastward and westward from these re-
(2002) showed that males are capable of metabolizing
gions, and may imply the presence of significant pollu-
chlordanes during a seasonal fast, while females are not.
tion sources in the Russian Arctic area. Regional differ-
The enhanced metabolic capability of males therefore, ex-
ences in pollution sources, contaminant transport, and
plains the lower levels of chlordanes and possibly some
prey preferences could also explain the variation in PCB
of the other compound groups in males. Lower levels of
and OC pesticide levels and patterns between regions.
PCBs and lack of an age effect in females are presumed
Ringed seals are assumed to be the most important
to be due to the additional losses from lactation.
and common prey of polar bears. However, Kleivane et
al. (2000) found an unexpectedly high number of bears
Influence of reproduction on OC levels in polar bears
on the ice east of Svalbard feeding on harp seals in June
To study the effect of fasting, gestation and lactation on
1995. Significantly higher OC concentrations were found
toxicokinetics, POP concentrations were determined in
in blubber samples from adult male harp seals from this
adipose tissue, plasma, and milk samples from seven fe-
area during their June 1995 molt (when they fast and
male polar bears and their cubs near Cape Churchill,
live off their blubber), as compared to ringed seals sam-
Hudson Bay, between 1992 and 1996 (Polischuk, 1999;
pled at the same time, which marks the very beginning
Norstrom, 2000). Pregnant females were captured from
of their molting season (Kleivane et al., 2000). Signifi-
August 7 to October 7, and the same females with cubs
cant species-specific differences were, however, detected
were captured from March 2 to March 17 of the follow-
only for HCHs and HCB, while differences in PCBs,
ing year before they had moved onto the ice to begin
DDTs, and CHLs were ascribed to age, xiphosternal
hunting seals. All females had therefore been fasting five
blubber thickness, and possible differences in xenobiotic
to seven months by the time of their second capture.
metabolizing capacity (Boon et al., 1992; Wolkers et al.,
Body composition of females was determined from 2H
1999). These results indicate that it is not necessarily the
dilution in blood, and body weight. The total body mass
species, but the time, availability, and biological condi-
of females declined by 43 ± 5%, and total fat mass de-
tion of polar bear prey that may play a major role in the
clined by 42 ± 3%. The proportion of mass lost as fat,
biomagnification of OCs at the top of the Arctic ecosys-
ranged between 55 and 66%.
tem (Kleivane et al., 2000).
During gestation and early lactation, the mean con-
centrations of PCBs, CHLs, and CBz in female adi-
OCs in Canadian polar bear plasma
pose tissue increased significantly by 2096 ±1292 ng/g
Concentrations of OCs were determined in the plasma
ww, 1600 ±1349 ng/g ww, and 49 ± 23 ng/g ww, respec-
of Resolute Bay polar bears (Norstrom, 2000; Sandau,
tively. Adipose tissue concentrations of DDT declined
2000) (Annex Table 14). This work also included plasma
by 91 ± 82 ng/g ww, while concentrations of HCH re-
samples from Svalbard polar bears. CHLs and PCBs
mained the same. Despite these increases in concentra-
were the dominant OC groups found in the plasma of
tion, POP body burdens in female polar bears declined
polar bears from both regions. OC concentrations were
during gestation and the early lactation period due
two times higher in subadults than adults except for
to loss of fat mass (Figure 4 ·54). In descending order,
DDT concentrations, which were similar. These results
the mean proportional decrease in body burdens was
were in line with previous findings in polar bear adipose
tissue. The exceptions were chlordanes, which were 30-
Body burden in polar bear adipose tissue lipids,
mg
60% lower in males, but concentrations were similar
350
comparing the same sex in both areas. PCB concentra-
July/August, pregnant
tions were similar in males and females from both areas,
300
March/April, spring cubs
and two to three times higher in the Svalbard bears, in
line with previous analyses of adipose tissue from these
250
areas (Norstrom, et al. 1998).
200
Influence of age and sex on OC levels in polar bears
150
The effects of age and sex are also important considera-
tions with respect to PCBs and OC pesticides in polar
bears. In 1995, Norstrom (1999a) examined concentra-
50
tions of OCs in male and female polar bears from Hud-
40
son Bay to test the effect of sex over a single year. Con-
30
centrations of OCs in males were similar to those in fe-
20
males; however, there was a (generally non-significant)
tendency for most residues to be lower in males, except
10
PCBs and DDTs, which were slightly higher in males.
0
DDTs
HCHs
CBz
CHLs
PCBs
The difference in PCBs between males and females was
not as large as observed in more extensive data sets.
Figure 4 · 54. Mean (± SD) body burden (mg) of major POPs in adi-
Norstrom et al. (1998) showed that males had 40%
pose tissue lipids of polar bear females on land, in the summer
4.4.7.2
(pregnant) and the following March (with cubs-of-the-year, COYs)
higher PCB concentrations than females on average.
in the Cape Churchill area, Hudson Bay (1992 - 1996). In all cases,
Younger male bears have PCB concentrations closer to
the difference in body burden between the two periods was statisti-
those in females, which may explain the similarity be-
cally significant.
118
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Concentration in polar bear milk,
ng/g lw
(5780 ng/g lw) in females that lost their cubs than in fe-
10 000
males that kept their cubs (1830 ng/g lw). It is not
known how much significance can be attached to this
Mother lost cubs
finding in terms of reproductive performance, but it is
Mother kept cubs
suggestive, at least, that cub survival may be dependent
on the degree of exposure to OCs in milk.
1000
In a study on Svalbard, 35 mother/cub pairs were
sampled during late March to mid-May in 1995-1998
(Lie et al., 2000). Blood plasma samples were analyzed
for six CBs (99, 118, 153, 156, 180, and 194), which
make up 78% of total PCB concentrations in polar bears
based on 28 congeners. Samples were grouped according
100
to age and reproductive status: cubs (cubs-of-the-year);
yearlings; females with cubs; and, females with year-
lings. Geometric mean PCB concentrations in plasma
were 12 300 ng/g lw in cubs, 5820 ng/g lw in females
with cubs, 6820 ng/g lw in yearlings, and 2945 ng/g lw
10
in females with yearlings (Annex Table 14, Figure 4 ·56).
DDTs
HCHs
CBz
CHLs
PCBs
Cub PCB concentrations were significantly higher than
Figure 4·55. Mean (± SD) concentrations of major POPs in milk of
the other three groups, and PCB concentrations in fe-
female polar bear with cubs, after emerging in March from dens in
PCBs in polar bear blood, ng/g lw
the Cape Churchill area, Hudson Bay (1992-1996). The data are
grouped according to whether the female still had her cubs the fol-
40 000
lowing fall, or had lost them. In all cases, the difference in concen-
trations between the two groups was statistically significant.
DDTs (75±8%) > HCHs (61±8%) > CBz (45±12%)
> CHLs (29±20%) PCB (24±16%), while the mean
mass of POPs lost was CHLs (71 ± 57 mg) > PCBs
(56 ± 34 mg) > DDTs (20±8 mg) > HCHs (14±7 mg)
> CBz (7±2 mg). Biotransformation during gestation
10 000
and lactation probably accounts for the greater propor-
tional decrease in CBz, HCHs, and DDTs compared
to PCBs and CHLs.
5000
The mean period between first and second capture
(mostly in their dens) was 188 ± 22 days, and the mean
number of days of lactation prior to sampling was ap-
proximately 79 ± 4 days. It is likely that the toxicokinet-
ics of OCs during the first 100 days were similar to that
during the subsequent summer fast. The polar bear cub
weighs only about 0.7 kg at birth (I. Stirling, pers. comm.,
Canadian Wildlife Service, Environment Canada, Ed-
monton AB) and two newborn cubs represent about 0.4%
1000
Cubs
Yearlings
Females
Females
of the mother's weight. Therefore OC transfer to the
with cubs
with yearlings
fetus is unlikely to be a significant part of the mother's
Figure 4·56. PCB concentrations in blood plasma of polar bears:
body burden. Thus, most of the 24-29% loss of body bur-
cubs (three to four months old), yearlings, females with cubs, and
dens of the poorly biotransformed CHLs and PCBs
females with yearlings (Lie et al., 2000). Dots represent individual
from the mother during the 188-day fast must have been
values.
transferred to the cub in milk during the 79-day lacta-
tion period prior to capture, at which time the cubs
males with yearlings were significantly lower than the
weighed 12.7 ± 0.9 kg. However, on average, only about
other three groups (p < 0.05).
25-50% of this body-burden loss could be accounted for
The PCB concentrations found in the adult bears
by CHL and PCB burdens in the cubs. Furthermore, a
and yearlings were comparable to those found in earlier
crude estimate of lactational transfer based on cub
studies on Svalbard (Bernhoft et al., 1997; 2000). No
growth rates could only account for half of the body-
previous studies of 3- 4 month old cubs on Svalbard
burden loss from the females. These discrepancies are
have been done. The results show that cubs and year-
difficult to reconcile and require further study.
lings have higher PCB concentrations than their moth-
Mothers that were recaptured in the autumn without
ers, probably due to lactational transfer. This has also
cubs had higher OC concentrations in their milk when
been seen previously in Canadian polar bears (Polischuk
emerging from their dens in spring. By comparison,
et al., 1995; Polischuk, 1999). Cub survival in the Sval-
mothers recaptured in the autumn and still accompanied
bard population is lower than in other populations, and
by cubs had lower OC concentrations in their milk the
the high PCB concentrations found in cubs compared
previous spring (Figure 4 ·55). The differences in con-
to older bears could be a possible explanation. There
centrations were significant for all residue classes. For
may be other causes, however, such as high population
example, PCBs were approximately three times higher
density.
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
119
Tissue distributions of OCs in female polar bears
(Fem/COYs); females with yearlings (Fem/YRLG); and,
In the vicinity of Cape Churchill, Hudson Bay, between
males. There were no single females sampled.
1992-1996, distribution of POPs in plasma relative to
Concentrations of CBz, CHLs, and PCBs in adi-
adipose tissue was determined in the following stages:
pose tissue lipid increased, and concentrations of DDTs
pregnant females in the summer at the beginning of the
decreased in all bears during the 47-68 day fast. The
on-land fast; females with cubs emerging from the den;
changes in concentration of CHLs and PCBs in adults
females with cubs in summer; and, females with cubs
were mostly significant. In COYs, the concentrations of
after 1-2 months fasting (Polischuk, 1999; Norstrom,
CHLs and PCBs increased 30%, while those of
2000). At all of these stages, the ratio of concentrations
HCHs and DDTs decreased by 20% and 34%, re-
of CHLs and PCBs in whole plasma to adipose tissue
spectively, during the fasting period. Increases in concen-
lipids was the same as the fraction of lipids determined
tration in adipose tissue in adults were entirely due to
in plasma, 0.01. That is, these POPs were equally dis-
utilization of lipids by the bears. Most of the increases in
tributed in adipose and plasma lipids. Plasma : adipose
concentration in COYs were due to decreased adipose
tissue ratios of CBz in pregnant females in summer and
tissue, not uptake from nursing. The body burden of
in females the following spring with cubs, and HCHs
CHLs and PCBs in females with COYs did not de-
in pregnant females were also distributed according to
crease during fasting. Taken together, these data suggest
lipid content. The plasma : adipose tissue ratios of CBz
that the COYs were nursing very little during the 47- 68
and HCHs were two to three times higher in plasma of
day period.
females with cubs in the summer and autumn than pre-
Biotransformation of p,p'-DDE and HCHs occurred
dicted by lipid content, suggesting that components of
in all bears during the fast, as did biotransformation of
the plasma other than extractable lipids were responsi-
oxychlordane and some other chlordane compounds
ble for some of the carrying capacity of plasma at these
in adult males. Chlorobenzenes, oxychlordane (except
times. The plasma : adipose tissue ratio of DDT was
males), and the major PCB congeners (CBs 60, 99, 138,
close to two times that of the lipid fraction in female
153, 156, 170, 180, and 194) were not metabolized or
plasma at all times. This is probably indicative of bind-
cleared by any other mechanism at a measurable rate
ing to proteins in plasma, as well as lipids. There was no
over 47-68 days of fasting.
indication that physical-chemical properties, such as wa-
In males, no age-related increases were found in con-
ter solubility or log Kow, were governing the partitioning
centrations of the compounds with slow biotransforma-
of POPs between plasma and adipose tissue.
tion rates during fasting, except highly chlorinated PCBs
Ratios of POP concentrations in milk lipids : female
(CBs 180 and 194). That is, average annual rate of in-
adipose tissue lipids were determined in spring, summer
take and excretion of the POPs are balanced. Clearance
and autumn. The ratio was greatest for HCHs and low-
of all POPs by a mechanism other than biotransforma-
est for DDTs and PCBs. On a lipid weight basis, the
tion is, therefore, occurring for at least part of the year.
ratio ranged from close to 1 :1 for PCBs and CHLs to
For most of the POPs, there was no significant difference
approximately 2 :1 for CBz and HCHs, indicating
in concentrations or trends in males and females. There-
that milk lipids were not at equilibrium with adipose tis-
fore, lactation is not governing the rate of excretion in
sue lipids for these compounds. The milk : adipose ratios
females, except perhaps for octa- and nonachlorinated
for CBz were significantly greater than CHLs, DDTs,
PCBs. The only clearance mechanism for slowly bio-
and PCBs. Similarly, ratios for CHLs were signifi-
transformed POPs that remains available to both sexes,
cantly greater than DDTs and PCBs.
is partitioning to gut contents and excretion in feces dur-
The ranking of the milk : adipose ratios for the chem-
ing periods when they are feeding.
ical groups was similar to that of the Kows for the chem-
Toxicokinetics of POPs in polar bears are therefore
icals (Hawker and Connell, 1988; Mackay et al., 1992),
likely to be variable with season, sex/reproductive sta-
unlike what was seen for plasma. Since it is improbable
tus, and area. Slowly biotransformed PCBs, oxychlor-
that concentrations in extractable milk lipids would be
dane (except in adult males), and chlorobenzenes will be
higher than those in adipose tissue on a thermodynamic
taken up and excreted in feces only during periods of ac-
basis, low Kow OCs must partition from adipose tissue
tive feeding. On the other hand, oxychlordane in males
to constituents of milk other than extractable lipids,
and HCHs and p,p'-DDE in all bears are taken up dur-
such as lipoproteins.
ing feeding periods, but biotransformed throughout the
year regardless of whether the bear is feeding or not.
Effect of seasonal fasting on whole-body toxicokinetics
Due to lack of ice from which to hunt seals during sum-
in Hudson Bay polar bears
mer and autumn in southwestern Hudson Bay, feeding may
POP concentrations were determined in adipose tissue
be restricted to 7-8 months of the year for males, solitary
from 47 fasting polar bears in the Cape Churchill area of
females and females with cubs or yearlings, and as short
western Hudson Bay during the summer to autumn of
as 4 months for pregnant females. In more northerly
1992-1995 (Polischuk, 1999; Norstrom, 2000). Body
areas, polar bears (except pregnant females) may not
burdens (mg/animal) were also determined based on
fast at all, if they can remain on the ice to hunt ringed
body composition determined from 2H dilution in blood
seal or have marine mammal carcasses to scavenge. In
and body weight. Adipose tissue, milk, and blood sam-
this case, uptake and clearance will occur year-round.
ples were taken when the bears came on land in July/Au-
gust. The same bears were recaptured and sampled in
4.4.7.1. `New' chemicals in polar bears
September/October (47-68 days apart) during the fast-
A number of `new' chemicals have been measured in po-
ing period. Five categories of bears were defined: cubs-of-
lar bears. As an apex predator, the polar bear has among
the-year (COYs); yearlings (YRLGs); females with COYs
the highest levels of POPs and is a logical organism to
120
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
utilize when searching for `new' chemicals. However, the
MeSO2-PCB had, respectively, 2, 9, 13, and 60 times
superior biotransformation capacity of polar bears may
lower levels than liver on a lipid weight basis. The major
also reduce levels of some chemicals below detection
congeners in all tissues were 3- and 4-MeSO2-CB87 and
limits.
3- and 4-MeSO2-CB 101. MeSO2-PCB uptake from seal
appears to be the most important source of MeSO2-
Perfluorinated compounds
PCBs in bears.
PFOS has been detected in liver of polar bears from
3-MeSO2-p,p'-DDE concentrations (303 ± 85 ng/g lw)
northern Alaska and in blood plasma of ringed seals
in liver were nearly half those of DDE and were 126 to
from Pangnirtung (Nunavut) and Svalbard (Giesy and
337 times higher than found in testes, adipose, and lung
Kannan, 2001; Kannan et al., 2001a). Other PFAs were
tissues. The highly asymmetric tissue distribution of
detected at lower levels but not reported (Kannan et al.,
MeSO2-p,p'-DDEs may be due to several factors, such
2001a; K. Kannan, pers. comm.). The levels of PFOS in
as the liver being the site of its formation or because of
polar bear liver are in the hundreds of ng/g ww range,
its highly selective binding in liver cells. It is not possible
suggesting that this compound is one of the most promi-
to resolve the relative importance of MeSO2-DDE bio-
nent individual organohalogen chemicals in polar bear,
accumulation versus formation in the polar bear based
when considering levels of PCBs, chlordane, and HCH-
on adipose tissue concentrations.
related chemicals (Norstrom et al., 1998). Levels in the
MeSO2-PCBs are efficiently transferred from polar
polar bear were higher than levels found in ringed seals
bear females to cubs via milk, resulting in concentra-
suggesting that PFOS can biomagify (Table 4 ·9).
tions that are approximately three times higher in the
cubs than their mothers, compared to approximately
PBDEs
two times higher for PCBs. 3-MeSO2-p,p'-DDE was not
Mean PBDE concentrations in polar bears from Sval-
preferentially transferred to cubs. Decreased cub sur-
bard are 17.5 ng/g ww (14-144 ng/g lw), in the same
vival is emerging as one of the major issues in eco-toxi-
range as minke whales and beluga from the Barents Sea
cology of polar bears. It is assumed that PCBs are the
area (Annex Table 17). PBDE concentrations are more
cause. However, MeSO2-PCBs are present at 8-10% of
than 100 times lower than PCB levels. The congener
PCBs in cubs, and their involvement in possible effects
pattern was dominated by BDE47 and a methoxy-
should be considered in any future studies.
TeBDE (van Bavel et al., 2001). This indicates that polar
Phenolic compounds and neutral POPs were identi-
bears may metabolize PBDEs, and therefore, the concen-
fied and determined in polar bear blood plasma from the
trations of parent compounds may not give an accurate
Resolute Bay area in the Canadian Arctic and Svalbard
picture of total exposure. No other data on PBDEs in po-
(Figure 4 ·57) (Norstrom, 2000; Sandau et al., 2000).
lar bears could be found in the literature for comparison.
Thirty-five compounds in the phenolic fraction were
identified as hydroxy-PCBs (OH-PCBs) in the two polar
Chiral compounds
bear populations. The OH-PCB identity number system
ERs of -HCH and several chlordane compounds were
follows that of the PCB system with the same chlorine
examined in the fat and liver of polar bears and the ringed
substitution pattern, with addition of the OH-group.
seals that they preyed on (Wiberg et al., 2000). The au-
Note that the precursor PCBs to the OH-PCBs fre-
thors found that polar bears frequently showed non-ra-
quently do not have the same chlorine substitution pat-
cemic (ER 1) mixtures of most compounds due to enanti-
tern, since chlorines shift on the ring during metabolism.
omer-specific biotransformation. As (+)- -HCH was trans-
In addition to OH-PCBs, a previously unidentified phe-
ferred up the food chain from ringed seals to polar bears,
nolic metabolite of OCS, 4-hydroxyheptachlorostyrene
it became more abundant relative to ()- -HCH. There
(4-OH-HpCS) was identified in polar bear plasma (San-
was no uniform trend for the ER changes in the various
dau et al., 2000). The compound was synthesized, and
chlordane compounds examined. It was also determined
the binding affinity to human TTR was determined to be
that oxychlordane was formed in ringed seals and me-
about 1.1 times that of T4. Therefore, it is most likely
tabolized by polar bears. In addition, the ERs of some
that 4-OH-HpCS is present in polar bear plasma bound
highly recalcitrant chlordanes in polar bear fat showed
to TTR. Traces of pentachlorophenol at approximately
linear relationships with age (Wiberg et al., 2000).
0.2 ng/g ww were also found.
Mean concentrations of OH-PCBs in polar bear
Metabolites of OCs in polar bears
plasma ranged from 57 ng/g ww in males from Resolute
There have been a number of comprehensive studies on
to 218 ng/g ww in females from Svalbard. Females had
OC metabolite formation, mainly MeSO2- and OH-
significantly higher concentrations of OH-PCBs than
PCBs, in polar bears (Letcher et al., 1996; Norstrom,
males. The ratio of OH-PCBs/PCBs in plasma was
1997; Sandau et al., 2000). Polar bears have superior
also significantly lower in females (mean 1.49) than
ability to biotransform OCs. For example, the PCB bur-
males (mean 4.08). It appears that females either have a
den in polar bears is dominated by a small number of
higher binding capacity for OH-PCBs in plasma (i.e.
congeners, much less than that observed in their major
higher TTR concentration) than males, or a higher ca-
prey item the ringed seal (Muir et al., 1988).
pacity to form OH-PCBs. The concentration of OH-
MeSO2-PCB and -p,p'-DDE metabolites were exam-
PCBs was two to three times higher than any other
ined in the tissues of polar bears shot in 1993 in Res-
residue class in female polar bear plasma. In the other
olute Bay (Letcher et al., 1996; Norstrom, 1997). Con-
age groups and males, the concentration of OH-PCBs
centrations of the MeSO2-PCB were highest in liver
was equal to, or higher than, the concentration of the
(3049 ±1290 ng/g lw) and represented 11% of the con-
next highest residue class, PCBs. The concentration of
centrations of PCBs. In fat, testes, lung, and brain,
OH-PCBs in subadults was the same as that in females.
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
121
164 175
Concentration in polar bear plasma, ng/g ww
100
Adults
;
Resolute, males
Resolute, females
80
Svalbard, males
Svalbard, females
;;
;
;
60
;
40
;
;
20
;
;
;
;
;
;
;
;
;
0
215
173
;
;
;
;
;
;
;
;
;
;
;
;
100
Cubs/juveniles
Resolute, juveniles
Resolute, cubs
80
Svalbard, juveniles
Svalbard, cubs
;;
;
;
60
;
40
20
;
;
;
;
0
;
;
;
;
;
;
;
;
;
;
;
;
;
4-OH-HpCS 4-OH-CB109 3-OH-CB153 4-OH-CB146
3-OH-CB187 4-OH-CB187
CI6 (RI-0.952)
3'-OH-CB180 4'-OH-CB172 4-OH-CB193CI8 (RI-1.332)
4'-OH-CB208
4,4'-diOH-CB202
Figure 4·57. Mean (± SD) concentrations of major OH-PCB congeners and OH-HpCS in plasma from polar bears from Resolute Bay in the
Canadian Arctic, collected in April-May 1997, and from Svalbard, collected in April-May 1998. Adult males and females, n = 12-15 in each
category; cubs (0 -2 yr) and juveniles (3 - 4 yr), n = 2- 5 in each category.
Thus, it appears that there is no selective transfer of OH-
probably in blood, and at low concentrations, it would
PCBs in polar bear milk, unlike MeSO2-PCBs.
seem that the potential for the polar bear to bioaccumu-
To put the importance of OH-PCBs and other pheno-
late OH-PCBs and 4-OH-HpCS is very low.
lic compounds in polar bear plasma into context, the
ranking of concentrations of the first 50 individual POPs,
4.4.8. Arctic fox and sea otter
both neutral and phenolic, was determined in the com-
bined Resolute Bay/Svalbard data set. Out of the ten
Arctic fox (Alopex lagopus)
highest POPs in plasma, six are phenolic compounds,
The Arctic fox is one of the few species that constitutes
three are PCBs, and the last one is oxychlordane. These
an important component of both the terrestrial and ma-
six phenolic compounds, including 4-OH-HpCS, consti-
rine ecosystems (Hiruki and Stirling, 1989). On land,
tuted 42% by weight of all POPs in polar bear plasma.
Arctic foxes feed mainly on lemmings, birds, and their
Of the remaining forty compounds, nine are chlordane-
eggs, as well as scavenging on caribou remains (Kenne-
related compounds, seventeen are PCBs, five are OH-
dy, 1980; Stickney, 1991; Kapel, 1999) whereas coastal
PCBs, and the rest are chlorobenzenes, DDTs, HCHs,
foxes will also eat marine invertebrates (Fay and Ste-
and pentachlorophenol (PCP).
phenson, 1989; Kapel, 1999) and fish (Banfield, 1987)
In order to determine the potential for bioaccumula-
in summer. In winter and spring on the sea ice, Arctic
tion of hydroxy metabolites of PCBs and OCS, patterns
foxes scavenge the remains of ringed seals and bearded
of accumulation of these metabolites and their precur-
seals killed by polar bears (Stirling and Smith, 1977;
sors were studied in ringed seal and compared to those
Andriashek et al., 1985; Fay and Stephenson, 1989;
in polar bear. Concentrations of OH-PCBs were 1000
Hiruki and Stirling, 1989; Kapel, 1999), and they will
times lower in ringed seal than in polar bear plasma,
also actively prey on newborn seal pups and eat placen-
whereas PCBs were only two times lower. Considering
tal remnants (Smith, 1976; Andriashek et al., 1985; Ly-
that most of the hydroxy metabolites in ringed seal are
dersen and Gjertz, 1986). Populations feeding at dif-
122
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
ferent trophic levels (Peterson and Fry, 1987; Hobson
HCH concentration in Arctic fox, ng/g ww
and Welch, 1992) and in marine or terrestrial/freshwater
100
environments (reviewed by Hobson et al., 1997) can
Liver
Muscle
be distinguished using stable isotope analyses. The
15N : 14N isotope ratio, often reported as 15N, increases
in a predictable manner between trophic levels (Kelly,
10
2000), allowing trophic positions and OC concentra-
tions to be interpreted along a continuous variable.
Carbon isotopes (13C/12C) are not enriched significantly
between trophic positions and can be used to evaluate
energetic pathways between regions with differing car-
1
bon sources. As a result, stable carbon isotope signa-
tures can differentiate an organism's dependence on in-
shore/benthic and offshore/pelagic regions (Hobson et
al., 1995).
0.1
Arctic fox muscle and liver tissues were collected
6
7
8
9
10
11
12
13
15N value,
at Barrow, Alaska, (n =18) and Holman, NWT, (n = 20)
from 1998 to 2000, to elucidate the feeding ecology of
Figure 4·58. 15N isotope ratio versus HCH concentrations in
this species, and relate these findings to body residue
liver and muscle tissue of Arctic fox (Hoekstra et al., 2003b). Rela-
tionship for muscle and liver samples are: log HCH = 0.175 15N
patterns of OC contaminants (Braune et al., 2001d;
1.04 (r2 = 0.67), and log HCH = 0.204 15N 1.07 (r2 = 0.59),
Hoekstra et al., 2003b) (Annex Table 14). At both sites,
respectively.
PCBs and chlordane-related compounds were the pre-
dominant OCs present in muscle, while in liver, chlor-
man Arctic fox population shifts its feeding from the ter-
danes were the predominant group, followed by PCBs.
restrial/freshwater systems to the marine environment,
The most abundant OC analytes extracted from Arctic
its relative trophic position significantly increases. How-
fox muscle and liver were oxychlordane, the principal
ever, most OC concentrations were not strongly corre-
metabolite of chlordane-related compounds, CB153 and
lated to trophic position. The comparison of 15N with
CB180. While mean concentrations of all major OC
OC concentrations indicated that trophic position does
groups were less than 250 ng/g ww, a few individuals
not serve as an accurate predictor for OC bioaccumula-
had very high levels of total PCBs and oxychlordane.
tion in the Arctic fox, possibly due to different turnover
The concentrations of OCs were relatively elevated on a
rates of OCs and stable isotopes in metabolically active
lipid basis. For example, PCBs ranged from 110 to 14
tissues, and/or the capacity of the Arctic fox to readily
600 ng/g lw in liver and from 76 to 8047 ng/g lw in
biotransform OCs.
muscle in the Holman foxes. The mean, lipid-adjusted
PCB concentrations in foxes from Holman and Barrow
(1853 ± 730 ng/g lw and 1516 ± 370 ng/g lw, respec-
tively) are lower than PCBs in Arctic fox liver from
Svalbard, the Norwegian mainland, and Iceland (Nor-
PCB concentration
in Arctic fox liver and fat, ng/g lw
heim, 1978; Wang-Andersen et al., 1993; Skaare, 1996;
50 000
Klobes et al., 1998b;), which is consistent with the
westeast gradient of PCB concentrations in ringed
40 000
seals (Muir et al., 2000b). The OC profile in the Arctic
2000
Pribilof Islands
fox suggests a similarity in metabolism with the polar
30 000
bear, and that the capacity of this species to biotrans-
20 000
form OCs dramatically influences accumulation pro-
files.
10 000
Barrow
PCB, DDT, and chlordane levels measured in fat of
0
young Arctic foxes from the Pribilof Islands, Alaska,
Fat Liver
(Krahn et al. 2002) (Annex Table 14) were higher, on a
Holman
wet weight basis, than liver and muscle concentrations
in Canadian foxes from Holman, NWT. On a lipid
weight basis, OC concentrations in the foxes from the
3
4
Pribilof Islands were also slightly higher than concen-
9
9
973-74
983-84
1
1
19
19
trations in the Holman foxes (Hoekstra et al., 2003b).
Svalbard
TEQs based on mono-ortho PCB concentrations range
from 3.4 to 146 pg/g ww, with means of 22.7 and 69.5
993-94
1
pg/g ww for females and males, respectively.
Iceland
Concentrations of several OC groups in both liver
and muscle samples were not significantly correlated
with increasing trophic position based on stable nitrogen
isotope (15N/14N) values from the Holman and Barrow
foxes (Hoekstra et al., 2003b). HCHs had the strong-
Figure 4·59. Concentrations of PCBs in Arctic fox liver and fat
est positive relationship with trophic position (Figure
from Pribilof Islands, Barrow, Holman, Iceland, and Svalbard (pre-
4 ·58). The stable isotope data suggest that as the Hol-
vious AAR data).
4.4.8.2
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
123
Concentrations of PCBs and a variety of OC pesti-
Barents Sea food web study
cides were measured in the livers of foxes from an inland
To study the bioaccumulation of OCs in the Barents Sea
and coastal region of Iceland (Klobes et al., 1998b)
food web, and to examine whether biomagnification
(Annex Table 14). In both regions, the foxes' OC pat-
could partially explain the high burden of contaminants
terns were dominated by oxychlordane. PCB was domi-
in top predators near Svalbard (Wang-Andersen et al.,
nated by CB 180, p,p'-DDE was dominant in the DDT
1993; Gabrielsen et al., 1995; Andersen et al., 2001b),
group of contaminants, and -HCH and -HCH were
selected taxa of zooplankton, fish, and seabirds were
the only detectable HCH compounds. PCB levels were
collected in the Barents Sea near Bjørnøya in June 1995
much higher in the coastal foxes (approximately 72 500
(Borgå et al., 2001). OC concentrations increased along
ng/g lw) than in inland foxes (approximately 1000 ng/g
the food web in a manner that mainly reflected the or-
lw). The PCB concentrations in coastal foxes are com-
ganisms' trophic position in the food web, as predicted
parable to concentrations previously seen on Svalbard
by previous dietary studies. The concentrations of OCs
(20 000 - 64 000 ng/g lw) (Skaare, 1996). This was ex-
(HCHs, HCB, CHLs, DDTs, and PCBs) were low
plained by the significant differences in trophic levels of
in zooplankton and fish, but biomagnified by one to
the two groups of foxes, where the coastal foxes con-
three orders of magnitude in seabirds, with the highest
sume prey items such as piscivorous birds and carcasses
concentrations being found in glaucous gulls. The low
of seals, and the inland foxes consume relatively more
OC levels in selected taxa at lower trophic positions
herbivorous species such as ptarmigan and geese. This is
were unexpected considering the high concentrations of
consistent with the findings of Hoekstra et al. (2003b)
particularly DDTs and PCBs in top predators. Since a
for foxes from Alaska and the western Canadian Arctic.
diet of pelagic organisms does not seem to explain the
PCB concentrations for all Arctic foxes, including
elevated concentrations found in top predators near
those studied previously on Svalbard, are presented in
Svalbard, in this case exemplified by glaucous gulls, a
Figure 4 ·59.
diet of ice-associated fauna may be of importance in the
bioaccumulation of OCs instead (Norstrom et al.,
Sea otter (Enhydra lutris)
1998). As suggested by Pfirman et al. (1995), contami-
Sea otters are an endangered marine mammal that
nated particles in the sea ice may be released in the melt-
inhabits the north Pacific Rim. These non-migratory
ing areas of the Fram Strait and the Barents Sea, fol-
animals are part of the mink family feeding on marine
lowed by bioaccumulation in ice-associated fauna.
shellfish, and therefore, may be particularly sensitive to
the effects of OCs. Members of the mink family have
Northern Norway food web study
been shown to be highly sensistive to the effects of OCs
Biomagnification of OCs was studied in the marine food
(Hornshaw et al., 1983). OCs were measured in the
web of Jarfjord, Norway (69°48'N, 30°25'E) (Ruus et
liver of sea otters collected in southeastern Alaska, the
al., 1999). Samples included two species of fish (lesser
Aleutian Islands, and California between 1988 and
sandeel (Ammodytes marinus) and cod) and seal (har-
1992 (Bacon et al., 1999). OC concentrations were
bour/grey seals) collected in 1989 and 1990. Most OCs
much lower in the Alaskan otters compared with
were found to biomagnify. The trophic level with the
the Californian otters with the exception of PCBs in
greatest biomagnification for DDTs was identified
the Aleutian otters (Bacon et al., 1999). PCB levels
from sandeel to harbour seal. The proportions of highly
in the Aleutian otters were 310 ng/g ww, 1.7 and 38
chlorinated PCBs, DDE and oxychlordane increased
times higher than those measured in the California
with trophic level, whereas PCBs that were mono-ortho
(180 ng/g ww) and southeastern Alaska otters (8 ng/g
substituted or meta-para-unsubstituted and DDD de-
ww), respectively. PCDD and PCDF levels were very
creased from fish to seal, reflecting the influence of bio-
low in all otter populations. The source of the high lev-
transformation. The study demonstrated the influence of
els of PCBs in the Aleutian islands is unknown and
physical-chemical properties and biotransformation on
remains a concern for the health of the sea otter popu-
food web dynamics of OCs in Artic marine food webs.
lation in this region. As a non-migratory animal, the
source of these high PCBs is likely local (Estes et al.,
Northwater Polynya food web study
1997).
OCs and stable isotopes of nitrogen ( 15N) were meas-
ured in zooplankton (six species), a benthic invertebrate
(Anonyx nugax), Arctic cod, seabirds (six species), and
4.4.9. Food web studies
ringed seals collected in 1998 in the Northwater Po-
A number of studies examining the food web transfer
lynya. The purpose was to examine the effects of biolog-
of OCs in marine food webs have been carried out
ical and chemical factors on trophic transfer of OCs in
since 1997, filling a knowledge gap identified in the
an Arctic marine food web (Fisk et al., 2001c). The
previous AMAP POPs assessment (de March et al.,
Northwater Polynya is located in northern Baffin Bay
1998). These studies incorporated a larger number of
and is the largest and most productive polynya (area of
species and trophic levels than was previously available
open water in ice-covered sea) in the Canadian Arctic.
for a single Arctic marine food web, and also incorpo-
The trophic relationships derived from stable isotope
rated stable isotopes of nitrogen to discern trophic posi-
analysis for the Northwater Polynya food web fell into
tions. They provide an advantage over relationships de-
the range expected based on stable isotope results for
veloped for the original AMAP POPs assessment, in that
another Arctic polynya food web (Hobson et al., 1995),
all samples were collected at the same time and in the
with seabirds and ringed seal at the top level, and zoo-
same region, and the analytical methods were consistent
plankton species occupying lower trophic levels. Strong
for all samples.
positive relationships were found between recalcitrant
124
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
CB180 concentration, ng/g lw
10 000
Pelagic zooplankton
Benthic amphipods
Arctic cod
1000
Ringed seal
Seabirds
100
10
1
0.1
Ivory gull
Glaucous gull
1000
Northern fulmar
Black-legged kittiwake
Black guillemot
100
Ringed seal (males only)
Thick-billed murre
Dovekie
Figure 4· 60. CB180 concentrations versus tro-
Arctic cod
10
A. nugax
phic level relationships for the Northwater Poly-
M. longal
T. libellula
nya marine food web (Fisk et al., 2001c). The
Sagitta sp.
top graph shows all data points and the bottom
C. hyperboreus
graph shows mean (± 1 SE) values for each spe-
E. glacialis
1
cies. Lines are log-linear regressions. Trophic
M. oculata
level is based on 15N.
1
2
3
4
5
Trophic level
OC concentrations (lipid corrected) and trophic level
plain the high biomagnification factors in seabirds com-
based on stable isotopes of nitrogen, providing clear evi-
pared to fish. Generally, PCBs and p,p'-DDE had the
dence of OC biomagnification in Arctic marine food
highest BMFs, followed by HCB and chlordanes. Com-
webs (Figure 4 · 60). Food web magnification factors
pared to other compound classes, the BMFs for HCHs
(FWMF), determined from the slope of OC concentra-
were low, reflecting the low Kow of HCHs. In general,
tion/trophic level relationships in this work, are in good
there was good agreement between BMFs for the two
agreement with values obtained for food webs from
studies, although there were some notable exceptions.
temperate and Arctic ecosystems involving marine birds
BMFs determined for amphipods, using copepods as
and mammals (Norstrom, 1994; Jarman et al., 1996).
the prey item, were one to two orders of magnitude
higher in the Northwater Polynya food web versus the Ba-
Biomagnification
rents Sea food web. Fisk et al. (2001c) suggested, how-
Biomagnification factors (BMFs, the ratio of lipid-ad-
ever, that the Northwater Polynya BMFs for zooplank-
justed concentration in predator to lipid-adjusted con-
ton were not realistic because concentrations of OCs in
centration in prey) values for the Barents Sea and North-
zooplankton may be controlled by OC concentrations in
water Polynya food webs are summarized in Table 4 ·10.
water and not prey (Fisk et al., 2001a). In addition, the
BMFs determined for the Northwater Polynya food web
higher concentrations in the amphipods may be driven
were corrected for trophic level differences based on sta-
by their larger size (Fisk et al., 2002a). Other variables,
ble isotopes because many of these species have varied
such as season, may influence invertebrate OC levels, and
diets, and for many of these comparisons the predator
this requires more research. BMFs for Arctic cod/amphi-
was not a full trophic level above the prey based on
pods were around 1, but are in the range of BMFs re-
15N values (Fisk et al., 2001c). Since BMFs reflect con-
ported for similar-sized fish in laboratory experiments
centrations throughout the food web, the lowest BMFs
(Fisk et al., 1998) and field observations (Rasmussen et
were found in trophic interactions with carnivorous zoo-
al., 1990). BMFs calculated for Northwater Polynya ringed
plankton (Parathemisto libellula) as predators on cope-
seals (Table 4 ·10) were slightly lower, but within the
pods. The BMFs were higher with fish as predators, and
range of those reported for male ringed seals from the
much higher when seabirds were the predators on zoo-
east central Canadian Arctic (Muir et al., 1988).
plankton and fish. In amphipods, Arctic cod, and cod,
The BMFs of seabirds, which used Arctic cod as the
the low OC concentrations and biomagnification factors
prey item, varied between species and food webs (Table
may be explained by their abilities to excrete contami-
4 ·10) and appear to be related to scavenging of marine
nants through the respiratory surface into water. The sea-
mammals and/or migration to more contaminated re-
birds' higher trophic position and energy requirements,
gions. The higher BMFs in the Barents Sea food web
and their lack of direct diffusion of contaminants can ex-
suggest that the diet of these seabirds includes a larger
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
125
Table 4 ·10. Biomagnification factors determined for key fauna in the marine food webs of the Barents Sea and northern Baffin
Bay. Biomagnification factors are based on lipid corrected concentrations. Biomagnification factors for Baffin Bay were corrected
to one full trophic level based on trophic levels derived from stable nitrogen isotopes.
Predator/prey
Site
HCB
HCHs
CHLs
p',p'-DDE
PCBs
Barents Sea
1.5
1.3
1.9
0.4
1.1
Amphipod/copepod
Baffin Bay
3.8
4.5
26.5
16
4.6
Barents Sea
2.0
1.2
3.5
1.7
2.2
Arctic cod/amphipod
Baffin Bay
6.1
1.1
1.6
3.1
0.9
Barents Sea
15
1.3
2.6
62
17
Thick-billed murre/Arctic cod
Baffin Bay
10.9
2.1
1.8
19
8.2
Barents Sea
8.6
1.1
3.9
40
19
Black guillemot/Arctic cod
Baffin Bay
5.0
3.5
4.0
18.5
8.9
Barents Sea
22
1.2
5.9
70
164
Black-legged kittiwake/Arctic cod
Baffin Bay
21.6
4.2
11.6
56
60.5
Barents Sea
105
6.8
73
2299
1144
Glaucous gull/Arctic cod
Baffin Bay
6.7
5.2
80
49
28
Ringed seal/Arctic cod
Baffin Bay
0.5
2.0
2.4
7.0
5.5
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Food web biomagnification factor (BMF)
4.1
2.7
7.0
14
4.6
percentage of higher trophic-level organisms than does
from 1 to 9 for readily metabolized OCs. These are
the Northwater Polynya food web. BMFs were highest
slightly lower than those calculated for glaucous gulls,
in black-legged kittiwakes and glaucous gulls, which re-
which is likely due to scavenging highly contaminated
flect the migration of the kittiwakes to more contami-
marine mammals by the glaucous gulls and/or from hav-
nated regions and the scavenging of marine mammals
ing a higher burden of POPs due to accumulation from
and predation on other birds by glaucous gulls. The ex-
more polluted winter habitats, as discussed above.
tremely high BMFs for the Barents Sea glaucous gulls
Results of these studies provided insights into the
suggest that scavenging and predation may be more pre-
fate and dynamics of OCs in marine food webs. The OC
valent in this population. BMFs reported for Arctic sea-
pattern in the Barents Sea food web changed from zoo-
birds are in the range reported for other fish-eating birds
plankton and fish to seabirds, with decreasing relative
(Braune and Norstrom, 1989; Hendriks, 1995). Braune
contributions of HCHs, HCB, and chlordanes to total
and Norstrom (1989) reported whole-body BMFs for a
OC concentrations, and increasing relative contribution
range of OCs, including PCBs in Lake Ontario herring
of DDTs, PCBs, persistent compounds, and metabolites
gulls that ranged from 18 to 59 for persistent POPs, and
(Figure 4 · 61). This corresponded to previous studies from
-HCH -HCH -HCH
Oxychlordane cis-chlordane trans-nonachlor
Glaucous gull
Kittiwake
Black guillemot
Thick-billed murre
Atlantic cod
Arctic cod
Amphipods
Euphasiids
Copepods
0
0.2
0.4
0.6
0.8
1.0
0
0.2
0.4
0.6
0.8
1.0
Contribution relative to HCHs
Contribution relative to CHLs
Tri- Tetra- Penta- Hexa- Hepta- Octa- Nona-/DecaCBs
HCHs HCBs CHLs DDTs PCBs Mirex
Glaucous gull
Kittiwake
Black guillemot
Thick-billed murre
Atlantic cod
Arctic cod
Amphipods
Euphasiids
Copepods
0
0.2
0.4
0.6
0.8
1.0
0
0.2
0.4
0.6
0.8
1.0
Contribution relative to PCBs
Contribution relative to OCs
Figure 4· 61. Relative proportions of individual OC compounds in the Barents Sea food web (Borgå et al., 2001).
126
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
other areas (Tanabe et al., 1984; Hargrave et al., 1992;
number of POPs. For example, DDE and heptachlor epox-
Ray et al., 1999). The high contribution of compounds
ide have values of FWMFs that are much greater than pre-
from the technical mixture of HCH ( -HCH and -
dicted based on the FWMF-log Kow relationships. DDE
HCH) and chlordanes (cis-chlordane and trans-nona-
has been well established as a metabolite of DDT formed
chlor) to HCHs and CHLs in zooplankton and fish is
in animals. These results suggest that a large percentage of
consistent with limited metabolic capacities of these or-
the high concentrations of DDE in upper trophic-level
ganisms. In contrast, high relative contributions of the
Arctic organisms are due to metabolic formation. Hep-
most persistent compounds and metabolites of HCHs ( -
tachlor epoxide, which is not in technical mixtures, is
HCH) and chlordanes (oxychlordane) in seabirds are con-
formed from heptachlor by photo-oxidation or in the
sistent with their higher ability to metabolize and excrete
liver of mammals (Buser and Müller, 1993). Results from
the other HCHs and chlordanes. The PCB congener pat-
this study suggest that heptachlor epoxide is formed in
tern, showing increased influence of higher chlorinated
upper trophic-level Arctic organisms, and may account
congeners with trophic position of the organism (Figure
for a large percentage of concentrations in these animals.
4 · 61), is consistent with the tendency of higher chlori-
nated congeners to biomagnify, since they are not readily
4.4.9.1. Trophic transfer of `new' and chiral chemicals
metabolized and excreted (Oliver and Niimi, 1988).
in marine food webs
One of the most striking differences in BMFs was be-
tween poikilotherms (fish) and homeotherms (seabirds
Concentrations of four organohalogens, that are possi-
and mammals) (Table 4 ·10). Large differences in BMFs
bly naturally produced (collectively termed HDBPs),
between poikilotherms and homeotherms were first
1,1'-dimethyl-3,3',4-tribromo-4,5,5'-trichloro-2,2'-
demonstrated in herring gulls and salmon for Lake On-
bipyrrole (DBP-Br3Cl3), 1,1'-dimethyl-3,3',4,4'-tetra-
tario (Braune and Norstrom, 1989). Greater BMFs, and
bromo-5,5'-dichloro-2,2'-bipyrrole (DBP-Br4Cl2), 1,1'-
hence, exposure to OCs in homeotherms, has been at-
dimethyl-3,3',4,4',5-pentabromo-5'-chloro-2,2'-bipyr-
tributed to their greater energy requirements and feeding
role (DBP-Br5Cl), and 1,1'-dimethyl-3,3',4,4',5,5'-hexa-
rates (Braune and Norstrom, 1989; Fisk et al., 2001c).
bromo-2,2'-bipyrrole (DBP-Br6), were quantified in the
A similar relationship was also seen in the Jarfjord study,
Arctic marine food web of northern Baffin Bay (Tittle-
with BMFs for the cod-sandeel predator-prey relation-
mier et al., 2001). The extracts used for this analysis
ship being lower (2 -3 for recalcitrant POPs) than for the
were also used for the OC analysis of the Northwater
seal-cod relationship (8 -10 for recalcitrant POPs) (Ruus
Polynya food web discussed in Section 4.4.9 but with
et al., 1999).
fewer species. All HDBP congeners were found to signif-
A strong relationship between FWMFs, determined
icantly biomagnify, or increase in concentration with
from concentration-trophic level relationships, and log
trophic level in the invertebrate fish seabird food
Kow was found for recalcitrant OCs (Figure 4 · 62). It is
web. None of the four HDBP congeners in ringed seals
clear that increasing log Kow results in greater trophic
followed the general trend of increasing concentration
transfer of recalcitrant POPs in Arctic marine food webs.
with trophic level, which was likely due to an ability of
This relationship provides insight into the behavior of a
the seals to metabolize HDBPs.
Metabolism of chiral contaminants can identify dif-
Food web magnification factor (FWMF)
ferences in species biotransformation ability and provide
14
DDE
insights into the fate of OCs in food webs. Concentra-
tions of HCH isomers ( , , and ) and EFs of -HCH
12
were determined in the northern Baffin Bay marine food
CB180
Mirex
web (Moisey et al., 2001), also discussed in Section
10
CB170/190
CB153
4.4.9. For invertebrates and fish, the BMFs of the three
CB156
CB138
isomers were >1, and the proportion of each isomer and
8
the EFs of -HCH were similar to those found in water,
CB99
CB183
Heptachlor epoxide
CB187
suggesting minimal biotransformation. Seabirds appear
CB74
CB178
to readily metabolize - and -HCH, based on low
6
DDT
CB105
CB118
BMFs for these isomers, high proportions of -HCH
HCB
(62-96%), and high EFs (0.65 to 0.97) for -HCH. The
4
Dieldrin
triCBz
DDD
- and -HCH isomers appear to be recalcitrant in
PCBz
CB56/60
ringed seals based on BMFs >1, with this species having
2
CB28
CB95/66
near racemic EFs for -HCH. The -isomer appears to
CB47/48
be recalcitrant in all species examined and had an over-
0
all FWMF of 3.9. EFs of -HCH provided conclusive
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
log K
evidence that biotransformation was accounting for much
ow
of the HCH isomer patterns observed in the northern
Figure 4·62. Relationship between food web magnification factors
Baffin Bay food web.
(FWMFs) and log Kow of recalcitrant POPs in the Northwater
Polynya marine food web (Fisk et al., 2001c). FWMFs were deter-
mined from the relationship between concentration (on a lipid
4.4.9.2. Trophic transfer of metabolites
weight basis) and trophic level. Log Kows of PCBs are from Hawker
4.4.9.3
and Connell (1988), and for all other POPs are from Mackay et al.
in polar bear food web
(2000). Regression lines are shown for PCBs (BMF = 22.7 + 4.4
Concentrations of MeSO2-PCBs and -p,p'-DDEs and
logKow, r2 = 0.72) and for `all' compounds (including PCBs, but ex-
cluding DDE and heptachlor epoxide (HE)) (BMF = 11.8 + 2.8
their precursor PCBs and p,p'-DDE were compared in
logKow, r2 = 0.64).
the Arctic cod ringed seal polar bear food chain
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
127
A R C T I C C O D
R I N G E D S E A L
P O L A R B E A R
CB
4/10
7/9
6
5/8
Reference congener CB153
17/18
Congeners that form
24/27
persistent MeSO2-PCB metabolites
15/32
28/31
Other congeners
20/23
< detection limit (0.5 ng/g lw)
22
45
49
52
47/48
47
44
42
37
41
64
74
70
95
66
91
56/60
60
84
101
99
97
87
85
136
110
151
149
118
146
153
105
178
141
130
137
138
187
183
128
132
156
157
174
180
170/190
170
194
195
206
209
0
0.2
0.4
0.6
0.8
1.0
0
0.2
0.4
0.6
0.8
1.0
0
0.2
0.4
0.6
0.8
1.0
CBx : CB153 ratio
Figure 4·63. Ratios of CB congener concentration to CB153 concentration in whole Arctic cod, ringed seal blubber, and polar bear adipose
tissue from the Resolute Bay area in the Canadian Arctic, in 1993 (Letcher et al., 1998).
from Resolute Bay to determine the relative importance
circumpolar coverage of information on OCs in the Arc-
of bioaccumulation from the food chain and formation
tic is greatest in the marine environment. Research has
by metabolism of precursors in polar bear (Letcher et
focused on this environment because OC levels are ele-
al., 1996; Norstrom, 1997).
vated in top predators due to long food chains; the fact
Overall, there was little difference in the PCB pattern
that the marine environment accounts for a large per-
in cod relative to the Aroclor standard (1242:1254 :
centage of the area of the Arctic; and, the fact that many
1260, 1:1:1). However, the PCB patterns changed no-
marine organisms are important components of the
ticeably in seal and bear, especially PCB congeners pos-
human diet.
sessing hydrogens at the meta-para (3,4) position on one
A number of studies have examined OCs in marine
or more ring (Figure 4 · 63). Meta-para PCBs were pres-
zooplankton, filling a knowledge gap identified in the
ent in seal blubber but notably absent in polar bear
first AMAP POPs assessment. As expected, levels of OCs
(< 0.05 ng/g lw). These PCBs included CBs 31, 49, 64, 70,
are low in marine zooplankton, reflecting their lower
91, 101, 110, 141, 132, and 174, all of which were also
trophic levels. Data are available for similar species from
present in the form of their 3- and 4-MeSO2-PCB me-
Alaskan, Canadian, and European Arctic waters, pro-
tabolites in seal and bear. Metabolites of CBs 52 and 95
viding almost circumpolar coverage; very limited data
were not found in the polar bear. These PCB congeners
are however available for Russian seas. In addition,
possess hydrogens at both meta-para positions, and may
there is no information on `new' chemicals in Arctic ma-
metabolize to bis-MeSO2-PCBs or to OH-PCBs.
rine zooplankton, which is necessary to assess the tro-
phic transfer of these chemicals to higher trophic levels.
The circumpolar trends of OCs in zooplankton differ
4.4.10. Summary and conclusions
marine environment
from those observed in higher trophic-level organisms,
in that there are no large differences between the North
The greatest amount of research on OCs in the Arctic
American Arctic and the European Arctic. In calanoid
since the previous AMAP assessment, post-1996, has
copepods from the Barents Sea and northern Baffin Bay,
been in the marine environment. As might be expected,
OC levels, with the exception of HCH and CBz, were
128
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
also similar. OC concentrations observed in copepods
spatial coverage for other Arctic species, some of which
from the Greenland Sea region were lower than those
play an important role in Inuit diets. As was reported in
observed in the North American Arctic, which differs
the previous AMAP assessment, levels of OCs in ringed
from the pattern of levels found in marine mammals
seals are greatest in the European and western Russian
from these areas. This could be due to a number of fac-
Arctic, in particular the Kara Sea, lower in the Canadian
tors related to the season of collection, which varied
Arctic, and lowest in the Alaskan Arctic and the
with these studies. HCH levels were found to be greatest
Chukotka Peninsula of eastern Russia. The exceptions
in Alaskan zooplankton, reflecting the proximity to
are for chlorobenzene concentrations, which have a uni-
Asian sources of these compounds. Ice-associated fauna
form circumpolar distribution, and HCH concentra-
from the marginal ice zone near Svalbard have low OC
tions, which are higher in the Alaskan and western Can-
levels, comparable with levels in zooplankton at similar
adian Arctic. OC concentrations in harp seal are much
trophic positions from the Barents Sea.
higher during their molt, when they live off their blub-
OC levels in benthic invertebrates varied to a greater
ber reserves. Higher PCB concentrations are also indi-
extent than in zooplankton. Benthic invertebrates that
cated in Steller sea lions from the Aleutian Islands com-
scavenge can accumulate OCs at levels similar to marine
pared to the Gulf of Alaska and southeast Alaska. Non-
fish and lower trophic-level birds. There are currently
and mono-ortho PCB and PCDD/Fs were determined in
insufficient data to examine temporal trends in these or-
a few species at a few sites. PCDD/Fs were fairly insig-
ganisms. Toxaphene was measured in spider crabs col-
nificant contributors to the TEQs compared to the PCBs.
lected north of Norway, demonstrating that this con-
Concentrations, as TEQs, were highest in ringed seals
taminant is present in invertebrates throughout the Eu-
from the Kara Sea followed by the Canadian Arctic and
ropean as well as the North American Arctic. Data for
Chukotka Peninsula. Northern fur seals had TEQs simi-
benthic invertebrates are lacking from Russia.
lar to Canadian ringed seals. Data for `new' chemicals
OC data for a number of marine fish species have been
have also been produced for ringed seals, including PCNs,
generated since the previous AMAP assessment, mainly
PBDEs, PFOS, and butyltins. From the limited data avail-
in Greenland and Canada but also for Arctic cod from a
able, it appears that PBDE levels are higher in European
number of regions. Very little new data are available for
ringed seals compared with Canadian ringed seals.
Russian marine fish. OC concentrations are higher in
Coverage of mysticete whale species has been im-
marine than in freshwater fish, and for some species, are
proved compared with the previous AMAP assessment.
very high. PBDEs have been measured in a small number
In particular, a large amount of data has been produced
of species from Greenland and Norway at levels much
for minke whales, providing good spatial coverage in the
lower than those of legacy OCs. Levels of OCs in Arctic
North Atlantic region. Spatial trends of OCs in minke
cod in the Barents Sea were similar to those in northern
whale are similar to other marine mammals, with the
Baffin Bay and Barrow, Alaska. OC concentrations were
highest OCs levels in the Kara Sea region of Russia and
found to be very high in the Greenland shark, a large
decreasing concentrations to the west and to the south
long-lived fish that feeds at a high trophic level.
(e.g., the North Sea). PCDD/Fs, non- and mono-ortho
A fair amount of new data has been produced for
PCBs and PBDEs have also been analyzed in minke
Arctic seabirds since the previous AMAP assessment.
whales around Svalbard. In addition, comprehensive
OC concentrations in seabirds vary dramatically be-
data have been produced for the bowhead whale in
tween species, reflecting the large range in trophic levels
Alaskan waters. In general, OC concentrations are lower
at which they feed. Highest OC concentrations are ob-
in the mysticetes (filter-feeding whales) compared to
served in the scavenging seabirds, in particular, great
odontocetes (toothed whales). There are limited `new'
skuas, great black-backed gulls, and glaucous gulls,
chemical data for these organisms.
which also prey on other seabirds, but migrating species
New data on odontocetes are available, and the be-
such as black-legged kittiwakes can also accumulate
luga is the most widely studied. Data for Russia contin-
high OC levels from southern habitats. Circumpolar
ues to be limited. There has also been improved cover-
trends of OCs in seabirds, particularly PCBs and
age of other odontocetes compared to the previous
DDTs, show highest levels in the Russian Barents Sea
AMAP assessment, but further improvement is still war-
(Franz Josef Land, Novaya Zemlya) and lowest concen-
ranted (e.g., for narwhal, which have POP levels as high
trations in the Canadian and Alaskan Arctic, with the
as in beluga and are also important to native communi-
exception of HCH. This is similar to what has previ-
ties). Comparison of OC levels in odontocetes from dif-
ously been observed. Data are limited for the central and
ferent regions shows a similar pattern as that seen in
eastern Russian Arctic. Various combinations of non-
ringed seals. Highest levels are found in Svalbard ani-
and mono-ortho PCBs and PCDD/Fs have been deter-
mals, and lowest levels are found in Alaskan animals.
mined in several seabird species from the Canadian and
HCH levels are again higher in belugas from Alaska.
Norwegian Arctic, and the Faroe Islands. Highest TEQ
Highest OC concentrations are found in transient killer
levels are found for glaucous gulls on Svalbard. Data for
whales, followed by resident killer whales in Alaska,
`new' chemicals, including PCNs, PBDEs, and butyltins,
long-finned pilot whales from the Faroe Islands, and
are also available.
harbour porpoises from northern Norway. PCDD/Fs,
There is wide coverage of POP concentration data in
non- and mono-ortho PCBs have also been analyzed in
a diverse group of pinniped species, both those that are
several species of odontocetes including beluga, harbour
typical Arctic species (ringed, harp, and bearded seals,
porpoise, and killer whale. A reasonable amount of data
walrus), and those that are not typically Arctic (harbour,
are available on `new' chemicals in odontocetes. PCNs,
grey, and northern fur seals, Steller sea lions). There is
PBDEs and endosulfan sulfate were found in beluga.
good geographical coverage for ringed seals, but limited
PBDE levels in these whales follow those found in ringed
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
129
seals, with levels higher in and around Svalbard. Highest
with age, and the rate of that change, are more variable
levels of PBDEs were seen in long-finned pilot whales
and probably depend not only on the female's level of
from the Faroe Islands region. Low concentrations of
exposure to contaminants, but also how often they suc-
butyltins were found in Norwegian harbour porpoise
cessfully produce and how long they nurse their off-
and Faroe Islands long-finned pilot whale, but were not
spring. Lipid content of tissues also plays a significant
detected in Canadian belugas.
role in contaminant accumulation, with OCs increasing
A large amount of OC data has been produced for
with the lipid content of the tissue.
polar bears, including studies on levels in plasma from
Although some new data have become available since
Russian polar bears. This is an important dataset be-
the previous AMAP assessment, there is still a lack of
cause it provides the most comprehensive spatial trends
contaminant data on marine mammals from the Rus-
coverage that includes Russia. The results clearly indi-
sian Arctic. This is particularly significant given that
cate that the Russian Arctic around the Kara Sea is the
available data indicate that the highest levels of many
most contaminated marine area of the Arctic, particu-
compounds in the marine environment occur in some of
larly for PCBs and DDTs. Levels decrease to the east and
the Russian seas.
west of the Kara Sea, with the lowest levels seen in
A number of comprehensive food web studies have
Alaska and the western Canadian Arctic. A number of
been carried out since the previous AMAP POPs assess-
`new' chemicals have also been measured in polar bears,
ment. These studies have increased our understanding of
including PBDEs and PFOS. PFOS levels are high in the
how OCs move through marine food webs. The studies
polar bear and require more study. There have also been
also show that OC levels, generally, are similar in lower
a number of studies that have examined factors that in-
trophic-level organisms (zooplankton, copepods, and
fluence OC levels in bears, including reproduction, sex,
Arctic cod) in northern Baffin Bay and the Barents Sea,
and fasting. Concentrations of MeSO2-PCB and -p,p'-
with the exception of HCH, which is higher in the North
DDE metabolites, OH-PCBs and a previously unidenti-
American Arctic. However, in seabirds, ringed seal, and
fied phenolic metabolite of OCS, 4-hydroxyheptachlo-
polar bear, there are clear spatial differences, with higher
rostyrene (4-OH-HpCS), have been determined in polar
concentrations of DDT and PCB, in particular, in the
bears and found to be high.
Barents Sea region as compared to the northern Baffin
New data for OCs have been generated for Arctic
Bay area. Thus, on its own, a diet of pelagic organisms
fox from sites in Alaska, Canada, and Iceland. Concen-
does not appear to explain the elevated concentrations
trations are related to food habits, with highest OC con-
in top predators in the Barents Sea area. The full expla-
centrations in foxes that feed in the marine food web.
nation for these spatial differences is, therefore, still un-
Mean PCB concentrations were lowest in Arctic fox
clear. All spatial trends that include the Russian Arctic
from Canada, Barrow, Alaska, and inland Iceland, and
clearly show, however, that PCB and DDT concentra-
higher in foxes from the Pribilof Islands, Alaska. The
tions are highest in the eastern Barents Sea and Kara Sea
highest concentrations were found in foxes from coastal
area, indicating significant local sources of DDTs and
Iceland, and these are comparable to those found previ-
PCBs to the Russian Arctic. This is also indicated by
ously on Svalbard.
high OC inputs from the Ob, Taz, Nadym, Pur, and
Within Alaska, OC concentrations (except for HCHs)
Yenisey Rivers, which have been shown to be major
were considerably higher in sea otters from the Aleutian
sources of OCs to the Kara Sea/Arctic Ocean via river
Islands than from southeast Alaska, indicating possible
water and sediments.
local sources.
Toxaphene congeners are being measured more of-
High levels of PCBs observed in blue mussels, sea ot-
ten, but there is still a need for a broader inclusion of
ters, and bald eagles from the Aleutian Archipelago in
these compounds in research programs, both as single
Alaska appear to be due to local contamination. All of
congener data, and as sum of congeners. Existing data
these species are non-migratory and would be exposed
indicate that levels vary significantly between species,
to contaminants from the local area. In the case of the
but recent data indicate that the highest levels are in the
bald eagles, high levels were observed in eagles nesting
thousands of ng/g range in cetaceans. Toxaphenes have
on islands that previously had military facilities. High
also been shown to be an important contaminant in the
p,p'-DDE levels in the bald eagles are correlated to re-
European Arctic.
duced reproductive productivity. A similar situation has
Data for brominated flame retardants, such as PBDEs
been found at Saglek Bay, Labrador, Canada, where local
are not widely available, and are needed, both for indi-
PCB contamination from a military radar site has led to
vidual compounds and sums. The highest reported levels
higher PCB levels in marine sediments, invertebrates,
are in the thousands of ng/g range in pilot whales, but
fish, black guillemot, and ringed seals. Local sources of
otherwise, are in the low ng/g range. Although PBDE
contamination in the Arctic warrant further considera-
concentrations are much lower than for legacy OCs,
tion and monitoring. Steller sea lions from the Aleutian
their rapidly increasing concentrations over time war-
Islands also have higher PCB concentrations in their
rant additional research and continued monitoring.
scat, indicating higher exposure there than in the Gulf of
Problems remain with the number of individual com-
Alaska and southeast Alaska. Whether this is also due to
ponents examined within a family of contaminants (e.g.,
exposure from local sources remains to be determined.
PCBs, chlordanes, DDTs, and toxaphene) with laborato-
In addition to regional influences, age, sex, and
ries continuing to report different numbers of com-
trophic level all play an important role in the accumula-
pounds, especially in the case of PCBs and chlordane.
tion of OCs in marine mammals. Although there are ex-
This continues to make it a challenge to compare results
ceptions, most commonly concentrations increase with
from studies within the Arctic as well as with those in
age in males. In females, changing contaminant levels
the temperate and tropical marine environments.
40
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Data were available for this assessment from the six
4.1.2. Air concentrations spatial trends
land-based stations: Tagish (Yukon, Canada); Alert (Nu-
navut, Canada); Pallas (Finland); Stórhöf
4.1.2.1. OC pesticides
i (Iceland);
Dunai (eastern Russia); and, Ny-Ålesund (Svalbard, Nor-
A full list of the OC chemicals monitored is given in
way). The data from the Norwegian, Icelandic, Finnish
Annex Table 2. Major OC pesticides in Arctic air are -
and Canadian stations were made available from the
and -HCH, p,p'-DDT, chlordane compounds, endosul-
AMAP Thematic Data Center for atmospheric contami-
fan, pentachloroanisole, as well as HCB (a multisource
nants at the Norwegian Institute for Air Research (Kjel-
chemical) (Halsall et al., 1998; Hung et al., 2002b). Un-
ler, Norway). In addition, selected results from the air
fortunately, not all of these compounds are measured at
monitoring station at Amderma in northwest Russia,
all locations. HCH and DDT-related compounds are
jointly operated (since March 1999) by Russia and Can-
compared in Figure 4·2 at five locations using average,
ada, were available for the assessment.
minimum and maximum concentrations in the gas + par-
The locations of these stations relative to possible
ticle phase (pg/m3) for different years. Results suggest
local, as well as long-range transported POPs, constitute
rather uniform average concentrations of -HCH iso-
an important consideration when evaluating spatial trends
mers and greater regional variation of -HCH. In all
(Figure 4·1). Most stations are at remote but well-estab-
Arctic samples, -HCH represents about 15-20% of the
lished research stations. Some are influenced by local
total - and -HCH burden. This distribution seems to
events such as forest fires, wood burning for domestic
be independent of the geographic location of the station.
heating, and garbage burning. This may be the case for
The lowest HCH average concentrations were meas-
the Tagish site in particular, as discussed further in Sec-
ured in the Stórhöfi and Amderma samples. The high-
tion 4.1.2.5.3. Samplers at Alert and Ny-Ålesund have
est average values were found at Ny-Ålesund and Alert
experienced contamination due to presence of OC pesti-
in 1996 (73 and 62 pg/m3 HCHs, respectively).
cides in building materials (Alert) and PCBs (Ny-Åle-
Highest average and maximum values of DDT-re-
sund). Altitude may also be a factor. Tagish is much
lated compounds were found at Stórhöfi. The contribu-
higher than all other sites and receives air from the
tion of the parent compounds o,p'- and p,p'-DDT, ac-
northeast Pacific Ocean
counts for more than 60% of the total DDT burden sug-
Alert, Tagish, Dunai, Amderma, and Ny-Ålesund op-
gesting fresh sources. The DDT group pattern at Am-
erate on a weekly sampling basis, while at Pallas sam-
derma also had a high proportion of p,p'-DDTs (50% of
pling is conducted one week per month, and Stórhöfi
DDTs). However, overall levels of DDTs at Amderma
reports data from samples collected over a two- to three-
were lower than Stórhöfi and similar to the other sites
week period. In order to compare results with the
(Figure 4·2). At Alert, summertime DDT/DDE ratios
weekly samples from the rest of the stations, the week of
of the order of 1-1.5 have been observed, whereas for
the sampling period was chosen for the comparison and
Amderma, the DDT/DDE ratios were about 3. A larger
the other weeks omitted. Using this approach, it was
DDT/DDE ratio has also been observed at Tagish in
possible to compare the data from all stations; however,
western Canada and is linked to trans-Pacific transport
the resolution of the Icelandic data is reduced and of
from Asia (Bailey et al., 2000). Higher DDT/DDE ratios
limited use for the elucidation of long-range transbound-
are indicative of fresh sources.
ary events.
Elevated maximum concentrations, indicating incur-
In the discussion that follows, average annual con-
sions of southern air with higher levels of -HCH and
centrations of selected POPs are compared among the
DDT compounds, occurred in spring and summer months
stations to examine prevailing spatial trends in the late
particularly at Ny-Ålesund, Alert, and Stórhöfi. Halsall
1990s. Results from shipboard measurements in the late
et al. (1998) also reported relatively uniform mean an-
1990s are also discussed. An assessment of long-term
nual concentrations of HCH and DDT isomers in Arctic
temporal trends in air from many of the same stations is
air collected in 1993 from Alert, Dunai, Tagish, and Ny-
presented in Section 5.1.1.
Ålesund. Back-trajectory results for the 1996 and 1998
Concentration in air, pg/ m3
Concentration in air, pg/ m3
200
12
-HCH
p,p'-DDT
10
150
8
100
6
Figure 4·2. Comparison of
average annual concentra-
4
50
tions of major HCH- and
2
DDT-related compounds in
0
0
air (gas + particle phase) at
50
10
monitoring stations in Ca-
-HCH
p,p'-DDE
nada (Alert), Iceland (Stór-
40
8
höfi), Norway (Ny-Åle-
30
6
sund, Zeppelin Mountain),
Finland (Pallas), (all 1996
20
4
and 1998), and western Rus-
10
2
sia (Amderma) (1999). Bars
0
0
represent the ranges.
Alert, 1996
Alert, 1998öfdi, 1996
öfdi, 1998
öfdi, 1996
öfdi, 1998
órh órh
lesund, 1996
lesund, 1998
Pallas, 1996
Pallas, 1998
Alert, 1996
Alert, 1998
órh órh
lesund, 1996
lesund, 1998
Pallas, 1996
Pallas, 1998
Å
Å
Å
Å
St
St
Amderma, 1999
St
St
Amderma, 1999
Ny- Ny-
Ny- Ny-
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
41
Concentration in air, pg/m3
8
Alert, 1996 and 1998
Stórhöfdi, 1996 and 1998
Ny-Ålesund, Zeppelin, 1998
1996
6
1998
4
1996
1998
2
0
28
31
52 101 105 118 138 153 156 180
PCB congener
8
Pallas, 1996 and 1998
Amderma, 1999
6
1996
1998
Figure 4·3. Comparison of average annual
4
concentrations of ten major PCB con-
geners in air (gas + particle phase) at mon-
itoring stations in Canada (Alert), Iceland
2
(Stórhöfi), Norway (Ny-Ålesund, Zeppe-
lin Mountain), Finland (Pallas), and west-
0
ern Russia (Amderma) (1996 -1999).
28
31
52 101 105 118 138 153 156 180
28
31
52 101 105 118 138 153 156 180
PCB congener
PCB congener
data shown in Figure 4·2 are not available. Harner et
Highest PCB10 concentrations were found at Ny-
al. (1999), however, measured HCH isomers during a
Ålesund compared to other sites (Figure 4·3). Results for
cruise in the Barents Sea and the eastern Arctic Ocean in
Alert were consistently lower than other sites. Amder-
July-September 1996 and found that concentrations and
ma, in northwest Russia, had average PCB10 of 4 pg/m3
proportions of -HCH increased in air masses that had
in 1999-2000 (the first year of site operations), similar
passed over central Europe. This is consistent with simi-
to Alert and lower than Pallas or Stórhöfi. Homologues
lar observations at Lista, Norway (Haugen et al., 1998)
at Amderma were more evenly distributed than at sites
and the southern Baltic Sea (Wiberg et al., 2001). In the
such as Alert and Tagish. There were similarities be-
Barents Sea and eastern Arctic Ocean, summertime,
tween Amderma and Dunai, another Russian site oper-
above-ocean concentrations of -HCH (11- 68 pg/m3)
ated in the mid-1990s. The concentration range of 5 to
and -HCH (6 - 68 pg/m3) measured by Harner et al.
30 pg/m3 for PCB10, or about 20-100 pg/m3 for total
(1999) were within the range observed at Alert and Ny-
PCBs, probably represents background levels independ-
Ålesund at the same time of year, but higher than at Pal-
ent of the station location. Air mass back-trajectories for
las and Stórhöfi.
Alert and Dunai, reported by Stern et al. (1997), showed
that the PCB profile of air masses passing over Russia
differed from air masses from the North American sec-
4.1.2.2. PCBs
tor by having higher proportions and concentrations of
Figure 4·3 presents the distribution of ten PCB congeners
penta- and hexachlorobiphenyls. Samples originating
(PCB10) (seven congeners for Pallas) measured at five sta-
over the northern Pacific had higher proportions of
tions in 1996 and/or 1998 or 1999. Results were not
trichlorobiphenyls.
available from all stations for all years. In particular, there
were blank problems at the Ny-Ålesund site so that the
4.1.2.3. PCDD/Fs
1996 data could not be used. Earlier measurements of
PCBs in air (1993-94) from Alert, Tagish, and Dunai have
During the winter of 2000/2001, 15 weekly filter sam-
been published (Fellin et al., 1996; Stern et al., 1997)
ples from Alert (particulate phase) were analyzed for
and, along with results from Ny-Ålesund and Stórhöfi
PCDD/Fs (Hung et al., 2002a). The sampling period co-
(Heimaey Island, Iceland), were discussed in the previous
incided with the occurrence of Arctic haze, when air-
AMAP assessment (de March et al., 1998). The congener
borne particulate levels are high. Since PCDD/Fs have
distribution is derived from annual average concentra-
similar properties to PAHs (e.g., both originate from
tions. In general, PCBs 28, 31, and 52 form the majority
combustion sources and have low volatility with high
of the PCB10 burden. Reporting of only ten PCB con-
tendencies to partition to aerosols), they are expected to
geners seriously underestimates the total PCBs in air and
follow similar seasonal cycles, and thus maximum con-
makes source identification problematic. For example,
centrations of PCDD/Fs were anticipated during winter
PCB10 represented only 11-27% of total PCB (based on
months. Table 4·1 (next page) compares the atmospheric
88 congeners) at Alert (1994), Dunai, and Tagish (Stern et
concentrations observed at Alert (week 49 of 2000,
al., 1997). Major contributors to total PCBs at Alert, and
weeks 3 and 7 of 2001) with those found at other loca-
probably at all Arctic sites, are the mono- and dichlorobi-
tions. The concentrations of both PCDDs and
phenyls (CBs 3, 4, 5, 6, 8, 16, 18). Nevertheless, PCB10
PCDFs observed were lower than those found at Ny-
was highly correlated (r2 = 0.80) with total PCBs at Alert,
Ålesund in the mid-1990s (Schlabach et al., 1996) and
which suggests that overall trends can be assessed.
lower than most other locations worldwide except the
42
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Table 4·1. Comparison of reported concentrations of PCDD/Fs in Arctic and tem-
perate air samples.
Location/dates
Total PCDD (fg/m3)
Total PCDF (fg/m3)
Alert, filter only (11/00-02/01)
2.1-13
2.4- 46
Ny-Ålesund (21/4-17/5/95) a
28
76
Ny-Ålesund (21/7-23/8/95) a
16
51
Trout Lake, Wisconsin (mid-1990s) b
240
180
Bloomington, Indiana suburban b
2500
2600
Nordrhein-Westfalen, Germany
3200
5500
urban and industrial b
Barbados (18/3/96 -13/8/97) c
6.8
12
Bermuda (4/6/96 -20/8/97) c
25
16
a Schlabach et al. (1996).
b Adapted from Table 3 of Luger et al. (1996).
c Calculated from supplementary material of Baker and Hites (1999).
ocean island locations of Bermuda and Barbados. The
from 1993 for Dunai were included in Figure 4·4 for
low PCDD/F levels are attributable to the remoteness
comparison with more recent results from Alert, Ny-
of Alert and the absence of anthropogenic activities
Ålesund, Pallas, and Amderma to give a broader per-
nearby. At the time of sampling, during the first week of
spective of prevailing levels in air. Temporal trends of
2001, Alert was mainly affected by air originating from
PAHs in air, using the long-term data, are presented in
the North Atlantic and North America. During the sec-
Section 5.1.1.3.
ond and third weeks, when the air concentrations of
All stations reported wide ranges of air concentra-
PCDD/Fs peaked at Alert, the origin of the air mass
tions of PAH11, ranging from less than 10 pg/m3 (the
shifted eastward further into Russia and Eurasia. After
approximate reporting limit) to 5000 pg/m3 (vapor
that time, the influence from Eurasia decreased while the
phase and particles). Highest average annual concentra-
North Atlantic sector regained dominance when the
tions of airborne PAH11 were found at Pallas and low-
concentrations tapered off during the fourth and fifth
est at Alert (Figure 4·4). PAH concentrations in air from
weeks.
the Ny-Ålesund station were similar overall to those at
Alert and Pallas, although some high maxima have been
recorded (maximum value of 5800 pg/m3 in 1997). The
4.1.2.4. PAHs
data from Amderma were missing results from winter
All stations reported up to 25 PAH compounds in at-
time and therefore, were not suitable for comparison.
mospheric samples to the AMAP database (see list in
Halsall et al. (1997) found clear seasonality in the
Annex Table 2); however, only 11 PAH compounds
PAH concentrations at Alert, Dunai, and Tagish (1993-
(PAH11) were reported from all stations. Thus, a level
94), with highest concentrations occurring during the
comparison for the compounds anthracene, benzo[a]an-
colder months. Highest concentrations of PAHs (18
thracene, benzo[a]pyrene, benzo[b,j,k]fluoranthene, ben-
unsubstituted PAH) were found at Dunai (2580 ± 2230
zo[g,h,i]perylene, chrysene, dibenzo[a,h]anthracene, flu-
pg/m3) during the winter period (November-March)
oranthene, indeno[c,d]pyrene, phenanthrene, and py-
compared to Alert (714 ± 579 pg/m3) and Tagish (312 ±
rene was performed (Figure 4·4). Airborne PAHs were
236 pg/m3). Air mass back-trajectories revealed that long-
not reported in the previous assessment of POPs or pe-
range transport from Eurasian sources gave rise to ele-
troleum hydrocarbons (Robertson, 1998). Results from
vated PAH concentrations at Dunai and Alert. These
Alert, Dunai, and Tagish from 1993 -1994 were, how-
elevated concentrations were also characterized by high
ever, reported by Halsall et al. (1997). Therefore, results
levels of dibenzothiophene, a marker of coal and oil com-
bustion, and by high ratios of benzo[a]pyrene (B[a]P) to
PAH concentration in air, pg/m3
benzo[e]pyrene (B[e]P) (0.6 - 0.8) which resemble urban
5000
air sources. Air at Ny-Ålesund was also characterized by
high B[a]P/B[e]P ratios (average 2.7) suggesting long-
4000
range transport, as well as possible influences from lo-
cal combustion on Svalbard. This suggests very limited
3000
breakdown of B[a]P in the troposphere during the win-
ter months. The B[a]P was 100% in the particulate phase
2000
during the winter period at all locations.
Halsall et al. (2000) developed a simple model to de-
1000
scribe the removal processes for four PAHs: fluorene,
phenanthrene, fluoranthene and benzo[a]pyrene, trans-
0
ported over a five-day period from the U.K. to the Arc-
Alert,
Ny-Ålesund,
Pallas,
Amderma,
Dunai,
tic. They noted that U.K. urban air was dominated by
1998
1998
1998
1998
1993
phenanthrene (52% of the sum of four compounds) and
Figure 4·4. Average and range of concentrations of PAHs in air (gas
had a relatively high proportion of B[a]P (3%). By con-
+ particle phase) from five Arctic air monitoring stations during the
1990s. Results are based on 11 PAH compounds that are monitored
trast, air at Dunai had much higher fractions of fluo-
at all stations.
rene. The more rapid degradation of phenanthrene by
4.1.2.4.1
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
43
Table 4·2. Current-use pesticides and other semi-volatile organochlorine compounds that are now being measured in Arctic air (gas phase)
during 1993-1994, pg/m3 (Halsall et al., 1998; Bidleman et al., 1999; 2000; 2001; Helm and Bidleman, 2003).
Alert
Tagish
Dunai
Compound
Mean
Min
Max
Mean
Min
Max
Mean
Min
Max
Current-use pesticides
Endosulfan
4.22
0.02
16.2
7.05
0.08
88.6
2.99
0.05
7.18
Methoxychlor
0.27
0.07
1.43
0.36
0.09
6.53
0.41
0.22
0.73
Trifluralin
0.12
0.03
0.64
0.16
0.04
2.92
0.18
0.09
0.13
Pentachloroanisole
3.03
0.1
20.5
3.28
0.04
73.4
2.92
0.95
6.92
By-products
Trichloroveratrole
0.93
0.05
10.1
1.85
0.07
20.6
1.49
0.15
3.65
Tetrachloroveratrole
0.19
0.05
0.99
0.25
0.07
4.52
0.44
0.15
2.19
Octachlorostyrene
0.79
0.04
2.96
0.67
0.07
11.9
0.60
0.11
1.74
Other halogenated compounds a
Polychlorinated naphthalenes
0.50
<0.01
1.00
0.30
<0.01
1.40
0.79
<0.01
2.60
Coplanar PCBs b
0.085
0.03
0.20
0.047
<0.01
0.11
0.41
0.19
0.82
Polybrominated diphenyl ethers
282
10
868
424
27
2127
14
0
62
Chlorinated paraffins (C10 - C13)
2.0
<0.4
7.3
a Based on retrospective analysis of 28-day composite samples from 1994 and January 1995 only.
b Coplanar PCB = Sum of CBs 81, 77, 118, 114, 105, 126, 156, and 169.
OH radicals, combined with a shift to the particulate
anisoles and tetrachlorodimethoxybenzene in air from
phase as air masses pass into the polar region, probably
waste treatment plants and in marine air over the tropi-
accounted for the removal of phenanthrene and other
cal Atlantic Ocean, suggesting that these chlorinated meth-
higher molecular weight PAHs.
oxylated aromatics are widespread in the troposphere.
OCS, a semi-volatile by-product of magnesium and
4.1.2.5. `New' chemicals in the Arctic atmosphere
chlorine manufacturing, was detectable at the three Arc-
tic stations studied by Halsall et al. (1998). While mean
4.1.2.5.1. Current-use pesticides
concentrations of OCS were low relative to many OC
and chlorinated by-products
pesticides, maximum concentrations were up to 15 times
Halsall et al. (1998) reported the presence of the cur-
higher, especially at Tagish, illustrating that long-range
rent-use pesticides endosulfan, methoxychlor, and triflu-
transport events from source regions are contributing to
ralin, as well as the pentachlorophenol metabolite, pen-
the presence of OCS. Actual source regions have not
tachloroanisole (PeCA), in air at Alert, Tagish, and Du-
been identified for OCS.
nai during 1993 - 94. PeCA and endosulfan were among
the top five pesticide-related compounds at all three sites,
4.1.2.5.2. PCNs and coplanar PCBs
exceeded in concentration only by total PCBs, HCB, and
- and -HCH (itself a current-use pesticide). Methoxy-
Polychlorinated naphthalenes, mono- and non-ortho sub-
chlor and trifluralin were also detected at sub-pg/m3 con-
stituted (coplanar) PCBs, polybrominated diphenyl eth-
centrations at all three sites (Table 4·2). Trifluralin vola-
ers, and chlorinated paraffins were determined in retro-
tilization from agricultural soils has been well document-
spective analyses of pooled archived extracts from Alert
ed (Majewski et al., 1998), and it has a very short atmos-
and Dunai stations from 1994, and reported by Bidleman
pheric half-life (Mackay et al., 1997). Its appearance in
et al. (1999; 2000; 2001), Harner et al. (1998), and Helm
Arctic air is therefore, surprising, especially at all three lo-
and Bidleman (2003). The extracts represented 28-day
cations. However, more than 5 106 kg was applied an-
composites (based on four weekly samples). Although use
nually in western Canada and U.S. in the mid-1990s for
of the archived extracts meant that extraction conditions
weed control in soybean, cotton, and cereal crops (NCFAP,
for these compounds were not optimized, the study nev-
2001). Concentrations at Alert in 1994 (Halsall et al.,
ertheless provided the first look at their presence in the
1998) were more than 1000 times lower than observed
Arctic as well as some information on seasonal variation.
over the Mississippi River by Majewski et al. (1998).
The PCN concentrations in 1994-1995 ranged
Methoxychlor had limited agricultural use on fruit
from < 0.01 to 1.00 pg/m3 at Alert, < 0.01 to 1.4 pg/m3
crops (NCFAP, 2001) as well as in home-gardening pro-
at Tagish (both Canadian sites), and from < 0.01 to 2.60
ducts. Methoxchlor is more stable to sunlight photolysis
pg/m3 at Dunai, Russia (Figure 4·5). The PCN levels at
than its chlorinated analog DDT, and thus may have a
Alert were within the range reported for 1993 (0.003 -
relatively long atmospheric half-life (Zepp et al., 1977).
0.077 pg/m3), while those at Dunai (0.001- 0.009 pg/m3)
Two other methylated chlorophenolics, trichlorove-
were comparable (Harner et al., 1998). PCN concen-
ratrole and tetrachloroveratrole, were reported by Hal-
trations at these High Arctic sites were lower than
sall et al. (1998) in air from all three sampling locations
PCNs observed at lower latitudes over the eastern Arc-
at sub-pg/m3 concentrations (Table 4·2). These compounds
tic Ocean, Norwegian Sea, and Barents Sea (Harner et
may originate from bleaching of wood pulp and chlori-
al., 1998). Elevated PCNs over the Barents Sea were
nation of wastewaters. However, their widespread detec-
associated with air trajectories from the North Sea cen-
tion at all three locations suggests other unknown sources.
tral Europe region, and, in subsequent work, Harner et
Führer et al. (1996) have reported a series of chlorinated
al. (2000) found especially high PCNs in urban air
44
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Concentration in air, pg/m3
Concentration in air, pg/m3
3.0
1.0
PCNs
Alert
co-planar PCBs
2.5
Dunai
0.8
2.0
0.6
1.5
0.4
1.0
0.2
0.5
0
0
1000
8
PDBEs (Br2 -Br7)
SCCPs (C10 -C13)
7
800
6
5
600
4
400
3
2
200
1
0
0
1-4
5-8 9-12
1-4
1-4
5-8
1-4
13-16 17-20 21-24 25-28 29-32 33-36 37-40 41-44 45-48 49-52
9-12 13-16 17-20 21-24 25-28 29-32 33-36 37-40 41-44 45-48 49-52
1994, week
1995
1994, week
1995
Figure 4·5. Concentrations of PCNs, co-planar PCBs, PBDEs and SCCPs in archived air samples (4-week composite samples from 1994 and
early 1995).
from the U.K. Higher PCN concentrations were found
The contribution to dioxin TEQs in air samples was
at Alert, Tagish, and Dunai in winter months (October-
calculated for PCNs and coplanar PCBs using relative
April) than in summer months (May- September) (Figure
potencies or toxic equivalency factors determined by H-
4·5). This is similar to the seasonality observed for PAHs
II-4 E bioassays for both PCNs (Blankenship et al.,
(Halsall et al., 1997), and suggests that PCNs, like
2000; Villeneuve et al., 2000; Kannan et al., 2001b) and
PAHs, may be combustion-related and associated with
PCBs (Giesy et al., 1997). Average TEQs (sum of TEQs
Arctic haze during winter/spring, or lost due to effects of
for PCNs, mono- and non-ortho PCBs) during the cold
photolysis in summer. In support of the former explana-
season of 1994 -1995 were 0.022 fg/m3 at Alert, 0.0075
tion, certain PCN congeners associated with combustion
fg/m3 at Tagish, and 0.061 fg/m3 at Dunai. PCNs con-
(e.g., CNs 13, 26, 29, 44, and 54) were enriched in the
tributed approximately 70 -74% of TEQs relative to the
winter air samples (Helm and Bidleman, 2003).
PCBs in air at Alert and Dunai and 31% at Tagish. PCN
The coplanar PCBs (non-ortho and mono-ortho sub-
congeners 66/67, 64/68, and 73 contributed most of the
stituted PCBs: CBs 81, 77, 118, 114, 105, 126, 156,
TEQs due to PCNs, while PCB congener 126 was by far
and 169) were also measured in the archived samples
the dominant contributor to coplanar PCB TEQ.
from 1994 to early 1995 (Helm and Bidleman, 2003) and
in an earlier set from 1993 (Harner et al., 1998). With
4.1.2.5.3. PBDEs
the exception of CBs 105, 118, and 156, these congeners
have not been determined previously in Arctic air. The
PBDEs have been determined in archived air samples
sum of these five congeners averaged 0.085 pg/m3 at
from the Canadian Arctic (Bidleman et al., 2001) and in
Alert, 0.047 pg/m3 at Tagish, and 0.41 pg/m3 at Dunai
a short air monitoring campaign on Bjørnøya (Norway)
for the 1994-95 set. Pentachlorobiphenyl congeners 118
in 1999-2000 (Kallenborn, 2002a). In the Canadian
and 105 were the dominant congeners at all sites. Sea-
study, PBDEs were measured in the same archived ex-
sonal variation was observed at the Dunai site with
tracts as the PCNs and coplanar PCBs (Bidleman et al.,
higher coplanar PCB concentrations during the summer
2001) (Table 4·2). Results for Dunai and Alert are shown
months, while no trend was evident at Alert and Tagish.
in Figure 4·5. A significant fraction of the PBDEs (10-
This agrees with the findings of Stern et al. (1997) that
25% for BDE47; 10-90% for BDE99) were present in
the contribution of PeCB congeners to PCBs increased
the particulate phase during the winter months. Levels of
in the summer, particularly at Dunai. The authors sug-
PBDEs in air samples from Dunai were much lower than
gested that emissions of Russian PCB mixtures with
at Alert. Much higher concentrations of PBDEs were
higher percentages of pentaCBs (PeCBs) could account
found in air samples from Tagish (Table 4·2). The con-
for this observation. Coplanar PCB concentrations were
centrations at Alert and Tagish were higher than air con-
elevated in shipboard samples collected from the Barents
centrations reported by Strandberg et al. (2001) for the
Sea in 1996 and, like PCNs, were associated with air
city of Chicago (mean of 52 pg/m3 for 1997 -1999) and
transport from Europe (Harner et al., 1998).
much higher than concentrations at air monitoring sites
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
45
in the Great Lakes (means of 5 - 23 pg/m3 at three sites).
in samples from the summer months, and were highest
In the case of Tagish, there is the possibility that inci-
in August. Individual homologue concentrations indi-
neration of household items in the region could contri-
cated that the chlorododecanes (C12), accounted for ap-
bute PBDEs to the air at the sampling site. At Alert, the
proximately 50% of the total, the bulk being from the
source has not been identified.
hexa- and heptachlorododecanes. Levels of SCCPs were
In contrast, the air concentrations of total PBDEs ob-
below detection limits in polyurethane foam plugs
served at Bjørnøya ranged from 3 -10 pg/m3 for the pe-
(PUFs) for periods other than summer months and also
riod of mid-December 1999 to mid-April 2000. The same
in all filters (Bidleman et al., 2001).
suite of PBDE congeners as Alert were detected, with
BDE47 predominating. Di- and TrBDEs (BDEs 13, 15,
4.1.3. Air and fog water measurements at Bjørnøya
and 33) also were prominent. While no summertime con-
centrations are available from Bjørnøya, the results sug-
In 1994, very high levels of PCBs in Arctic char and sed-
gest that levels are much lower than at Alert or Tagish
iment from the lake Ellasjøen on Bjørnøya (Bear Island,
but similar to levels in rural areas of the Great Lakes.
74°N, 19°E), situated about 500 km southwest of Sval-
Thus, the reported results for Alert are probably not typ-
bard (Skotvold et al., 1999), prompted a comprehensive
ical of concentrations of PBDEs in Arctic air, although
research study which was started in 1999 (Evenset et al.
they could be typical of low-temperature burning which
2002; Kallenborn, 2002a; 2002b). The studies included
is common in Arctic communities in Canada and Al-
investigation of the influence of atmospheric long-range
aska. Further measurements are being conducted in an
transport on POPs at the Ellasjøen area on Bjørnøya.
effort to better understand the levels and potential sources
This included the measurement of POPs in ambient air,
at Alert. The main PBDE congeners observed at all sites
snow, and fog water (Annex Table 3). Fog water was in-
were BDEs 47, 99, 100, 153, and 154 with BDE99 hav-
cluded based on information provided by the Norwe-
ing the highest concentrations. BDE47 predominated
gian Meteorological Institute that, on average, fog events
in all Great Lakes samples (Strandberg et al., 2001), as
were occurring more than 30% of the time in summer,
well as in air samples in Sweden (Bergander et al., 1995;
and to assess fog as medium for transport and deposi-
de Wit, 2002). Mono-, di- and triBDEs were found in
tion pathways at Bjørnøya. A total of 20 air samples (av-
air samples from Alert, which may indicate photode-
erage volume: 1000 m3) were collected every second
gradation (debromination) of PBDEs during long-range
week in 1999 and spring 2000. In the Ellasjøen catch-
atmospheric transport. The PBDE results, if typical, im-
ment area and at the meteorological station on Bjørn-
ply significant air contamination by these compounds.
øya, four fog water samples (approximately 50 L) were
Air concentrations are higher than for PCBs at the
collected during the 2000 summer sampling campaign.
same sites.
Continuous POP monitoring in ambient air at the
`Zeppelin Mountain' atmospheric research station (Ny-
Ålesund, Svalbard) provided an excellent comparison
4.1.2.5.4. SCCPs
for the Bjørnøya air samples. Typical POP distributions
SCCPs were analyzed in the same archived extracts from
in air samples from Bjørnøya (meteorological station)
Alert that were analyzed for PCBs, coplanar PCBs, and
and the Ny-Ålesund measuring station are presented
PBDEs. SCCPs were above method detection limits only
in Figure 4·6. In general, the air concentrations of
Concentration in air, pg/m3
100
Ny-Ålesund,
Zeppelin Mountain
17-19 October 1999
Ny-Ålesund
25-27 October 1999
50
Bjørnøya
0
100
Bjørnøya
13-15 July 1999
2-4 November 1999
50
Figure 4·6. POP concentrationsin am-
bient air from the Bjørnøya (Bear Is-
land) meteorological station and the
`Zeppelin Mountain' atmospheric re-
search station at Ny-Ålesund (Sval-
0
bard) in 1999.
HCB
-CHL
-CHL
-NO
-HCH -HCH
cis
tris
CB101 CB105 CB118 CB138 CB153 CB156 CB180
trans
-nonachlor
trans
46
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Concentration in fog water, pg/ L
4500
4000
Meteorological station
Meteorological station
July 1999
3500
May 2000
3000
2500
2000
1500
1000
500
0
Ellasjøen
4500
4000
Ellasjøen
July 1999
3500
September 2000
5 km
3000
100 m contour intervals
2500
2000
1500
Figure 4·7. POP concentrations in fog
1000
water from Bjørnøya meteorological
500
station and the Ellasjøen catchment
0
area in 1999.
HCB-HCH-HCH
CB52 CB99CB101CB105CB118CB126CB128
CB149CB153CB156CB169CB170CB180CB183CB187CB194
CB28/31
CB138/163
POPs were similar in ambient air collected at the Ny-
4.1.4. Passive sampler measurements
Ålesund station and at Bjørnøya, with HCB dominat-
ing in all air samples from both stations. The compari-
Airborne concentrations of PCBs and HCB were meas-
son of the PCB patterns, however, reveals remarkable
ured by passive air samplers (semipermeable membrane
differences.
devices, SPMDs) along a latitudinal transect from the
PCB concentrations in air samples from Ny-Ålesund
south of the U.K. to the north of Norway during 1998-
are dominated by the lower chlorinated congeners.
2000 (Meijer et al., 2003b). This work is part of an on-
However, the medium chlorinated PCB congeners domi-
going air sampling campaign in which data were previ-
nate the Bjørnøya air samples. Usually, the latter PCB
ously gathered for 1994-96 (Ockenden et al., 1998). The
pattern is characteristic for biological samples. The
SPMDs were exposed for two years in Stevenson screen
dominance of the medium chlorinated PCBs (CBs 153
boxes at remote sites in the U.K. and Norway. Se-
and 138) is particularly evident in the sample taken in
questered amounts generally decreased between the two
summer (13 -15 July 1999). During this period of the
sampling periods by a factor 2-5 over four years, sug-
year, the cliffs, mainly south of Ellasjøen, are populated
gesting half-lives of 1.7- 4 years. Spatial trends of the
by thousands of nesting seabirds. Therefore, one hypo-
1998-2000 data show a decrease in absolute sequestered
thesis for the unusual POP pattern is that the guano of
amounts of the heavier PCBs with increasing lati-
seabirds redistributes into the air around Bjørnøya, and
tude/distance from the source area, whereas the lighter
contributes significantly to the elevated POP air levels at
PCBs were more equally distributed along the transect
Bjørnøya as the dominating local source during summer
(Figure 4·8). However, relative sequestered amounts (ex-
time.
pressed as a ratio to PeCBs)) show a clear latitudinal
Medium chlorinated PCB congeners also predomi-
trend with the relative contribution of the lighter con-
nated in fog water samples collected at Bjørnøya, indi-
geners increasing with increasing latitude, providing evi-
cating the strong influence of local biological sources
dence of latitudinal fractionation. Absolute amounts of
(e.g., seabird guano) on POP patterns (Figure 4·7). The
HCB were found to increase with increasing latitude,
influence of possible biological sources is also supported
suggesting that this compound is undergoing cold con-
by the predominance of -HCH in Bjørnøya fog. Sea-
densation and global fractionation (Meijer et al.,
sonal differences are even more pronounced in fog sam-
2003a).
ples compared to ambient air, probably due to the prox-
imity of seabird cliffs and hatching areas in the Ellasjøen
4.1.5. Precipitation
catchment area. The September sample from Ellasjøen
(2000) showed low PCB concentration levels, whereas
4.1.5.1. Background
fog samples collected in July 1999 at the end of the nest-
It is well known that snow and ice play an important
ing season at Bjørnøya had concentrations of PCBs
role in the hydrological cycle of the Arctic, but they also
(e.g., CB118) that were approximately ten times higher.
play a strong role in the behavior of POPs in the envi-
Comparable seasonal differences could not be found
ronment by modifying chemical cycling between the at-
in the fog water samples from the meteorological station
mosphere and the Earth's surface. Snow deposition was
(16 km north of Ellasjøen), probably due to the absence
studied extensively in the Canadian Arctic in the early
of large seabird colonies.
1990s and results were reviewed in the previous AMAP
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
47
Ratio to PeCBs
Ratio to PeCBs
Ratio to PeCBs
0.6
0.8
2.5
TriCBs
TetraCBs
HexaCBs
0.7
0.5
2.0
0.6
0.4
0.5
1.5
0.3
0.4
1.0
0.3
0.2
0.2
0.5
0.1
0.1
0
0
0
50°N
55°N
60°N
65°N
70°N
75°N
50°N
55°N
60°N
65°N
70°N
75°N
50°N
55°N
60°N
65°N
70°N
75°N
80°N
0.7
0.06
HeptaCBs
OctaCBs
0.6
0.05
70°N
0.5
0.04
0.4
60°N
0.03
0.3
0.02
0.2
50°N
0.01
0.1
0
0
50°N
55°N
60°N
65°N
70°N
75°N
50°N
55°N
60°N
65°N
70°N
75°N
Figure 4·8. Latitudinal trends of PCB homologues in air in northwestern Europe determined using semi-permeable membrane devices
(SPMDs) (Meijer et al., 2003b). Results are expressed as ratio to PeCBs. Sites 7 and 8 (crosses) represent outliers omitted from the regression.
POPs assessment (de March et al., 1998) and in Mac-
4.1.5.2. Wet deposition
donald et al. (2000). Studies of POPs in snow on sea ice
in the Russian Arctic were also assessed in the previous
Bulk deposition of PAHs (31 congeners), PCBs (seven
AMAP assessment report. No additional work, however,
congeners) and HCHs (three congeners) was studied at a
appears to have been conducted on POPs in snow in the
site in northern Finland (Pallas and Oulanka) and south-
Canadian or Russian Arctic during the second phase of
ern Finland (Evo) in the summers 1993-2001 (Figure
AMAP. However, sampling and analysis of snow was
4·9) (Korhonen et al., 1998; Korhonen et al., 2002). In
conducted in northern Alaska, Svalbard and northern
1993-1994, the sampling in northern Finland was con-
Norway.
ducted at Oulanka, approximately 100 km south of Pal-
Flux, µg/m2/ month
80
70
PAHs
60
50
40
30
20
10
0
J J A S O
J J A S O
J J A S O
J J A S O
J J A S O
J J A S O
J J A S O
J J A S O
1.6
1.4
HCHs
1.2
1.0
0.8
0.6
0.4
0.2
0
J J A S O
J J A S O
J J A S O
J J A S O
J J A S O
J J A S O
J J A S O
J J A S O
25
20
PCB 7
15
Figure 4·9. Fluxes of PAHs (sum of 31
compounds), HCHs, and total PCB
10
(estimated from analysis of seven con-
geners) from rainfall at Oulanka (1993-
5
1994) and Pallas (1995-) in northern
Finland during the summer months
0
(June -October), 1993 - 2000.
J J A S O
J J A S O
J J A S O
J J A S O
J J A S O
J J A S O
J J A S O
J J A S O
1993
1994
1995
1996
1997
1998
1999
2000
48
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
las. This program represents the longest continuous pre-
tilized and accumulate in small amounts in snow. The
cipitation monitoring program within the Arctic. Rain-
less volatile Te- and PeCB homologues accumulate in
fall was collected using a glass funnel bulk sampler (30
relatively large amounts in the upper meter of snow, but
cm in diameter) (Korhonen and Kiviranta, 2002). The
significant amounts of them may evaporate back into
mean deposition values of PAHs were 27.7 µg/m2/month
the atmosphere before final burial, resulting in larger
in southern Finland and 17.9 µg/m2/month in northern
proportions of Hp- and OcCB homologues in the deeper
Finland. The main PAH components in both southern
snow layers. The high snow surface percentage of the
and northern Finland were phenanthrene, fluoranthrene,
Te- and PeCB homologues, and the lower percentages of
and pyrene. PCBs averaged 1.6 µg/m2/month in the
Hp- through NoCB homologues suggests that some
south and 1.1 µg/m2/month in the north. CBs 153 and
post-depositional volatilization may be occurring. This
138 predominated among the seven congeners meas-
is plausible if the homologue distribution of PCB de-
ured. Mean HCH fluxes were 0.5 µg/m2/month and
posited to Lomonosovfonna has not changed. The over-
0.3 µg/m2/month in the south and north respectively,
all pattern of homologues at the Lomonosovfonna Ice
and -HCH was the predominant isomer reflecting lin-
Cap shows a higher proportion of more highly chlori-
dane use in the Baltic region (HELCOM, 2001). Over-
nated PCBs than observed by Gregor et al. (1995) on the
all, the deposition of all chemical groups was about
Agassiz Ice Cap on Ellesmere Island.
30% higher in southern Finland than in northern Fin-
The snow accumulation rate at Austfonna is nearly
land. The temporal trends of PCBs in wet deposition at
twice as high as Lomonosovfonna, and is more than
Pallas are discussed in more detail in Section 5.1.2.
twice as high as Summit. Thus, fluxes are the most ap-
propriate way to compare among sites. The proximity of
Lomonosovfonna to population centers on Svalbard
4.1.5.3. Fluxes of POPs in surface snow
makes it more likely to accumulate local contaminants
Garbarino et al. (2002) analyzed snow cores taken over
than Austfonna, as indicated by the pesticide data. The
the sea ice from two northwestern Alaska estuaries,
high flux of DDTs at Lomonosovfonna, nearly nine
Kasegaluk Lagoon, and Admiralty Bay, in 1994-95.
times greater than Summit, suggests a significant, pos-
They found non-detectable levels of most persistent OC
sibly local source. Other pesticides (HCHs, dieldrin,
pesticides. However, quantitation limits in the study
and endosulfan ( - and -isomers)) are all higher at
were high (e.g., 4 ng/L for -HCH) which precluded de-
Lomonosovfonna than at Austfonna and Summit. Sam-
tection of most compounds. POPs were measured in sur-
ples from Summit show the highest flux of PCBs, about
face snows and snow cores (see Section 5.1.3) from
25% greater than Lomonosovfonna. The flux of HCB is
Summit (Greenland) and on the Lomonosovfonna and
the lowest of any observed compound, but is 70%
Austfonna glaciers in Svalbard, for `legacy' OC pesti-
greater at Summit than at Lomonosovfonna. By compar-
cides and PCBs, by Hermanson et al. (2002) and Mat-
ison, surface fluxes for PCBs on the Agassiz Ice Cap
thews (2001) (Table 4·3). Lomonosovfonna is the high-
were about 200 ng/m2/yr in 1992/1993, and ranged
est ice sheet on Svalbard at approximately 1250 m
from 50 to 650 ng/m2/yr in lower layers (Gregor et al.
above sea level (asl). It is about 35 km from Pyramiden,
1995). PCB deposition at Mould Bay in the Canadian
75 km from Longyearbyen and 110 km from Barents-
High Arctic ranged from 400 ± 300 to 600 ± 500 ng/m2/yr
burg, all coal-mining towns on western Svalbard. Aust-
in 1990 -1991 and 1992 -1993, respectively (Franz et al.,
fonna is approximately 600 m asl, and is located 180 km
1997).
northeast of Lomonosovfonna. Summit (3230 m asl), the
Although flux measurements for PCBs in snow from
highest point on Greenland, is roughly 1300 km west-
mainland Norway are not available for comparison,
southwest of Svalbard.
Carrera et al. (2001) reported concentrations of PCBs
The PCB profile in near-surface snow layers from
at Ovre in western Norway (63°N, 7°E) of 730 ng/L.
Lomonosovfonna is shown in Figure 4 ·10. The volatility
DDTs and HCHs were below detection limits in
of PCB declines with increasing chlorine substitution
the same samples. In northern Norway at a site near
(from left to right in the diagram). The homologue dis-
Tromsø, Enge et al. (1998) collected snow in stainless
tribution of PCBs suggests that the more volatile Di- and
steel lysimeters and reported PCB (eight congeners)
TrCBs remain largely in the atmosphere or are revola-
concentrations ranging from 1500 to 3600 pg/L sam-
Table 4·3. Concentrations (pg/L) and fluxes (ng/m2/yr) of chlorinated pesticides and PCBs in Arctic glacial snow from Lomonosovfonna and
Austfonna (on Svalbard) and Summit (Greenland). (Matthews, 2001; Hermanson et al., 2002).
Snow accumulation Collection
Endo
Site
L/m2/yr
year
HCB
HCHs
CHLs
DDTs
Dieldrin
sulfan
PCBs
pg/L
pg/L
pg/L
pg/L
pg/L
pg/L
pg/L
Lomonosovfonna
340
2000
3.4
169 xx
137xx
550 xx
87.7
85.2
575
Austfonna
657
1998
n.m.
14.1
n.m.
n.m.
11.4
13.2
n.m.
Summit
293
2000
8.2
36.2
105xx
83.6
94.2
25.2
994
ng/m2/yr
ng/m2/yr
ng/m2/yr
ng/m2/yr
ng/m2/yr
ng/m2/yr
ng/m2/yr
Lomonosovfonna
340
2000
1.2
57.4
46.6
187 xx
29.8
29.0
195
Austfonna
657
1998
9.3
7.5
8.7
Summit
293
2000
2.4
10.6
30.7
24.5
27.6
7.4
291
n.m. = not measured.
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
49
% of total PCBs
50
40
30
20
Depth in snow
0-0.5 m
0.5-1.0 m
1-4 m
4-10 m
Figure 4·10. PCB homologue distribu-
10
tion at various near-surface depths in
snow cores from the Lomonosovfonna
glacier on Svalbard (Hermanson et al.,
0
2002).
Di-
Tri-
Tetra-
Penta-
Hexa-
Hepta-
Octa-
Nona-
PCB homologue group
pled over a three-month period. PCB concentrations in
limit, but increased until the 1980s. In general, NAP
surface snow from the same site were 1040 pg/L, reflect-
concentrations (5000-53 000 ng/g) at Lomonosovfonna
ing volatilization from the snow pack.
were six times lower than in the Agassiz Ice Cap (Peters
et al., 1995), but are about fifty times higher than in
PAHs
Greenland (Jaffrezo et al., 1994).
Summit, at the centre of the Greenland Ice Cap (3230 m
asl), has been the main location for investigations of
4.1.5.4. `New' chemicals in snow and ice
PAHs in Arctic glacial snow cores. Jaffrezo et al. (1994)
determined dissolved and particulate bound PAHs in a
Garbarino et al. (2002) reported detection of the insecti-
snow core from Summit, collected in 1991, representing
cide chlorpyrifos in snow from two northwestern Alaska
four years of deposition. They observed a strong correla-
estuaries at concentrations ranging from <10 to 80 ng/L
tion between sulfate and total PAH in the snow with
as well as the herbicide dacthal (detectable near the
maxima in winter/spring and summer minima. Total
quantitation limit of 4 ng/L). Chernyak et al. (1996) had
PAH averaged 1360 ng/g (range 600-2370 ng/g) in the
previously reported chloropyrifos at 0.17 ng/L in melted
combined dissolved and particulate phases. The pattern
sea ice samples from the Bering Sea. Dacthal has not
of PAH compounds in the surface snow indicated that
been reported previously in Arctic samples but has been
fossil fuel combustion was the major source as well as
shown to be transported regionally in North America
biomass burning. Major PAH compounds were naph-
(Rawn et al. 1999).
thalene, phenanthrene, fluoranthene, pyrene, benzo[a]-
Laniewski et al. (1998) analyzed ice samples from
pyrene and benzo[g,h,i]perylene. The latter compound
the Mårma glacier in the Swedish Arctic (68°10'N,
comes mainly from combustion of coal and petroleum
18°40'E) and detected a number of chlorinated organics
(Mascelet et al., 1986). Peters et al. (1995) analyzed
not previously reported in snow or wet deposition in the
snow collected from the Agassiz Ice Cap in 1993 as part
Arctic. The tri(chloroalkyl)phosphates (TCAPs) were
of a study of a snow core. They found naphthalene
present in the ice sample from the Mårma glacier and
(NAP) was by far the major PAH present, representing
snow from southern Sweden and Poland, but were not
88% of PAHs (16 compounds). Similar to the observa-
present in ice from Queen Maud's Land in Antarctica.
tions of Jaffrezo et al. (1994), phenanthrene, fluoran-
The isomers detected were tris(2-chloroethyl)phosphate,
thene and pyrene were the major 3- and 4-ring PAHs
tris(1-chloro-2-propyl)phosphate, and bis(1-chloro-2-
present. Excluding NAP, PAH concentrations at Agas-
propyl)(3-chloro-1-propyl)phosphate. These compounds
siz were 19 ng/L, significantly higher than at Summit.
are semivolatile (vapor pressures 1-10 Pa at 25°C;
Peters et al. (1995) estimated an annual deposition of
(WHO/IPCS, 1998)) and have come into increasing use
PAHs (16 unsubstituted PAH compounds) to the
during the 1990s for use as flame retardants in plastics.
Canadian Arctic and subarctic of 37 t per year in the
Also detected in the glacier were dichlorobenzenes and
1980 -1990s, based on a deposition flux of 11 µg/m2/yr.
tetrachlorobenzene (Laniewski et al., 1998).
Masclet et al. (2000) found PAH concentrations of 1.2
ng/g in particulate matter filtered from melted snow (5-
4.1.5.5. Snow and rain deposition at Bjørnøya
12 L volumes) in surface snows from the Greenland Ice
Snow and meltwater were collected in 1999/2000 in
Cap. The PAH levels had pronounced seasonal trends
order to assess transport and deposition pathways of
coinciding with Arctic haze events (see Section 5.1.3.2).
POPs within the Bjørnøya ecosystem (Evenset et al.,
Measurements of PAHs were performed on a 122 m ice
2002; Kallenborn, 2002a). This was in connection with
core record from the Lomonosovfonna glacier on Sval-
the measurement of POPs in ambient air and fog (see
bard, but only NAP was detectable (Vehviläinen et al.,
Section 4.1.3) in a study addressing high POP levels in
2002). This was attributed to the very small (average 56
sediment and Arctic char. During a first, preliminary
g) sample sizes. The results suggested that prior to the
sampling campaign in 1999/2000, two meltwater sam-
1930s, NAP concentrations were below the detection
ples and one deposition snow sample were collected for
50
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Table 4·4. POP levels in snow deposition and meltwater samples from Bjørnøya (pg/L)a
Meteorological station
Ellasjøen
Sampling Period
Sample type
PCBs HCHs HCB
Sampling period
Sample type
PCBs HCHs HCB
May 2000
Snow
7220
78
2
Summer 2000
Snow
3200
32
1
July-Sept. 2000
Meltwater 1b 1180
490
i.c.
June-Sept. 2000
Meltwater 4b
391
921
i.c.
Sept.-Nov. 2000
Meltwater 2b
845
1800
i.c.
July 1999
Meltwater 3b
3740
740
n.a.
a PCBs = 17 congeners, HCHs = - and -HCH, HCB = hexachlorobenzene.
b During the summer period of the year, a substantial amount of rain deposition was collected in addition to snow.
i.c. = interference in the chromatogram, n.a. = not analyzed.
POP analyses at the meteorological station. At the lake
The same analytical method was used for meltwater
Ellasjøen, two meltwater and three snow deposition
samples collected at the valley Dividalen in Norway and
samples were quantified. Meltwater was sampled at the
at Bjørnøya (Ellasjøen and meteorological station). Con-
meteorological station and Ellasjøen using a 1-m2 melt-
centrations of HCHs and PCBs in Bjørnøya meltwa-
water collector. Surface snow was collected over a long
ter were comparable with those from the Norwegian
period of time (1- 2 months) and allowed to melt under
mainland site. PCB levels of 3600 and 1500 pg/L were
natural conditions. Thus, the meltwater sample repre-
found in two meltwater samples from Dividalen. The two
sented an integrated sample over a long period of time.
meltwater samples taken at the Bjørnøya meteorological
The POP pattern of the meltwater sample was influ-
station had slightly lower levels of PCBs than the El-
enced by remobilization and volatilization processes.
lasjøen and the Dividalen samples. No distinct difference
PCBs were the dominant OC contaminants in snow
in the PCB levels between the Bjørnøya samples and the
(Table 4·4), while HCHs were the main contributors for
meltwater taken at the Norwegian mainland was found.
the chlorinated pesticides in snow and meltwater from
This is a rather surprising result, since no local PCB
Bjørnøya. In two meltwater samples (Meltwater 2 and
source is known at Bjørnøya, whereas possible sources
Meltwater 4), HCH was the predominant compound
close to the Dividalen sampling site are known. The ex-
class (Table 4·4). Due to relatively high volatility, HCB
tent to which biological sources such as seabird guano,
probably re-volatilizes into the atmosphere and there-
influence the PCB levels, patterns, and distribution of
fore dominated in Bjørnøya ambient air samples but not
other POPs in snow remains to be determined, however.
in meltwater and snow. The highest PCB concentrations
were found for snow deposition, collected close to the
4.1.6. Summary and conclusions
meteorological station.
air and precipitation
These findings indicate characteristic differences found
for the distribution of HCHs and PCBs in snow deposi-
Measurements of POPs in Arctic air have continued on a
tion and meltwater. In all snow deposition samples, only
weekly basis at locations in Canada, Iceland, Norway,
minor contribution from HCHs was found. However,
Finland, and Russia. A large temporal-trend dataset is
the contribution of HCH to the overall contamination is
being developed as discussed in Section 5.1. With six
significantly higher in meltwater samples (Figure 4·11).
stations reporting results during the 1990s (although not
This may partly be caused by re-evaporation of lower
all operational in all years), it is possible to examine ge-
chlorinated PCBs into the atmosphere and the parallel
ographical differences in concentrations of major OCs
continuous uptake of water soluble - and -HCH from
and PAHs among sites and to compare these with results
the atmosphere. However, the number of samples ana-
from monitoring stations in southern Canada/U.S. and
lyzed is too small to draw final conclusions about this
Sweden. At three stations, results were also available for
hypothesis regarding snow surface/atmosphere exchange
some current-use pesticides and flame retardants.
processes. It should be noted that during the summer
In this assessment, spatial comparisons were limited
season, both rain and snow deposition were collected
to a relatively small suite of OCs that have been meas-
and therefore, a direct correlation between meltwater
ured at all stations and reported to the AMAP data cen-
properties and POP contamination is difficult.
ter. Thus, only PCB10 congeners have been measured at
all stations, although data are available for up to 102
%
Meteorological Station
Ellasjøen
congeners at some sites. The reporting of PCB10 under-
100
estimates total PCBs in air by four to five times because
HCHs
mono- and dichlorobiphenyls, which predominate in
80
Arctic air, are underrepresented in the list.
60
Results for HCHs, chlordane, and DDT-related com-
pounds suggest uniformly low concentrations of these
40
pesticides in Arctic air during the mid- to late 1990s.
PCBs
This is expected because, with the exception of -HCH,
20
all others have been banned for at least ten years or
more in circumpolar countries, although there may be
0
Snow 1
Meltwater 1
Meltwater 2
Snow 4
Meltwater 4
some use of DDT continuing in Russia (see AMAP, 2003).
The concentrations of these three OC pesticides in Arctic
Figure 4·11. Percentage distribution of HCHs and PCBs in snow
and meltwater samples from Bjørnøya (Bear Island).
air were lower than in air at a rural site in the Great
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
51
Table 4 ·5. Comparison of average concentrations of persistent OCs and PAHs in the Great Lakes and at several Arctic locations for approx-
imately the same time period. Concentrations (pg/m3) represent combined gas and particulate (filter) phases.
Great Lakes rural a,c Great Lakes urban b,c
Alert Ny-Ålesund
Stórhöfi
Amderma
1996-98
1996-98
1996-98
1996-98
1996-98
1999-2000
Mean
SE
Mean
SE
Mean
SE
Mean
SE
Mean
SE
Mean
PAHs 1160
100
113000 15500
274
34.3
2750
320
HCHs 97
7.2
131
10
37.2
3.1
55.7
2.8
22.2
1.3
CHLs
9.4
1.1
151
15
2.0
0.2
1.9
0.1
0.5
0.01
DDTs 4.5
0.66
80.2
7.9
0.8
0.1
2.1
0.2
2.6
1.2
HCB 68
2
110
6
40.8
3.2
94.0
6.6
9.8
1.2
PCBsd
63
6
1800
170
7.3
0.6
125.0
35.9
67.4
19.1
4.1
a Eagle Harbor western Lake Superior.
b Chicago (downtown).
c In the Great Lakes samples, HCH represents the sum of - and -HCH. CHLs represents the sum of cis- and trans-chlordane and trans-
nonachlor. DDTs represents the sum of the p,p'-isomers of DDT and its two metabolites, DDE and DDD.
d Sum of 100 PCB congeners in Great Lakes samples and PCB10 4 for Alert, Ny-Ålesund, Stórhöfi, and Amderma.
Lakes region near the shore of Lake Superior (Eagle
Tenerife were similar to levels measured at Ny-Ålesund
Harbor) during the same time period (Table 4 ·5). How-
and Stórhöfi (78 pg/m3 at 2367 m and 190 pg/m3 at sea
ever, the differences between this temperate North Am-
level), taking into account the difference in the number
erican site and the Arctic stations were less than a factor
of congeners.
of 2 for DDTs at Ny-Ålesund, Stórhöfi, and Amderma.
The past five years has seen a major increase in the
Concentrations of PCBs and HCB at Ny-Ålesund are
number of halogenated organic chemicals detected in
higher than in rural air in the Great Lakes (Buehler et al.,
Arctic air. Among the current-use pesticides, the pres-
2001). All other Arctic sites have lower average levels
ence of trifluralin is surprising because of its short at-
than the rural Great Lakes. The air sampling building at
mospheric half-life. Trifluralin is a common air contam-
Ny-Ålesund was replaced in 1998 (completed by August
inant in agricultural areas of the U.S. and Canada and is
1998) and the elevated CB28 and 31 concentrations ob-
present at ng/m3 concentrations during application peri-
served during the remainder of 1998 may be related to
ods in May - June (Grover et al., 1988; Hoff et al., 1992;
contamination during startup of the new location, al-
Majewski et al., 1998). Thus, the high volume of triflu-
though similar concentrations were found in 1999 and
ralin use results in detectable levels of this pesticide, and
2000 (see Section 5.1). Urban air (Chicago) has much
possibly others such as methoxychlor, even though re-
higher concentrations of PCBs and PAHs than any Arc-
moval processes in the atmosphere are quite rapid. The
tic sites as expected (Table 4 ·5). Combined with results
presence of similar levels of trifluralin at Dunai implies
from Dunai and Stórhöfi, where PCB concentrations
Asian and Russian uses of this pesticide.
were also higher than at Alert and in the upper Great
The presence of PCNs in air at Alert and over the Ba-
Lakes, the results suggest that, during the period of
rents/Kara Seas found by Harner et al. (1998) is an im-
1996 -1998, the European Arctic continued to receive air
portant new finding. The PCNs contribute significantly
with elevated PCB concentrations compared to the
to total TEQs in air and are correlated with PAHs, sug-
North American Arctic.
gesting that they are combustion by-products associated
Although there are fewer data for PAH, higher PAH
with Arctic haze. The Arctic haze association is impor-
levels are seen at Dunai and Svalbard than at Alert, Tag-
tant because the annual PCN profiles seem to be meteo-
ish (Halsall et al., 1997) or Lake Superior (Buehler et al.,
rologically driven, with maxima in winter. A full evalua-
2001), which also suggests that the European Arctic is
tion of their importance requires concurrent measure-
receiving elevated atmospheric inputs in comparison to
ments of PCDD/Fs as well as coplanar PCBs. These com-
the western Canadian and High Arctic archipelago. Fur-
pounds have not yet been routinely measured and to do
ther assessment of the importance of European and par-
so may require modification of sample extraction meth-
ticularly Russian sources of PAHs for air concentrations
odology to optimize their recovery from the particulate
over the Barents Sea awaits more complete datasets from
phase, as well as increased air volumes for some sam-
the station at Amderma in northwestern Russia and Pal-
pling stations.
las in northern Finland.
A pilot study conducted at Alert revealed that al-
Concentrations of pesticides and PCBs in Table 4 ·5
though levels of PCDD/Fs found in air were low, there
can also be compared with those found at Tenerife
are still possibilities of significant accumulation of these
(Canary Islands) (28°N, 16°W) during 1999 - 2000 (Van
compounds in other Arctic environmental media due to
Drooge et al., 2002). Samples were taken in the free tro-
the low temperatures in the Arctic and slower degrada-
posphere at 2367 m asl altitude and near sea level at 47
tion processes. The PCDD/Fs also have to be considered
m asl. Concentrations of all substances were higher
in the context of coplanar PCBs and PCNs. Further
within the marine boundary layer than at high altitude,
measurements of PCDD/Fs are needed in order to gain
except for HCB, which appears to be very well mixed
more insight into the fate of these compounds in the
throughout the troposphere. The free tropospheric con-
Arctic given predictions of significant deposition in
centrations were similar to those found at Arctic stations
Nunavut. A report by Commoner et al. (2000) has fo-
for HCB (51 pg/m3), HCHs (17 pg/m3) and DDTs (5
cused attention on the current levels, pathways, and
pg/m3). PCB concentrations (sum of 19 congeners) at
sources of PCDDs and PCDFs in the Canadian Arctic.
52
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
In their study, Commoner et al. (2000) predicted dioxin
and birds are however important as food species (e.g.,
TEQ deposition of about 4 to 53 pg TEQ/m2/yr to ter-
caribou), and levels of OCs could be an issue for human
restrial surfaces near eight communities in Nunavut.
consumption. Temporal trends in birds of prey remain
Highest deposition in the south and east was predicted
an important data set but temporal trend studies in other
because of the preponderance of dioxin sources in the
species, such as lichen or caribou, have not been carried
eastern U.S. and Canada. Russian and northern Euro-
out or continued. More volatile, less bioaccumulative
pean sources were regarded as insignificant for Nunavut
OCs, in particular HCH, are the most common individ-
in comparison to those in the mid-west U.S. and Ontario
ual compounds found in soil and lower trophic-level ter-
and Quebec (Commoner et al., 2000).
restrial organisms. At higher trophic levels, such as in
The presence of PBDEs in Arctic air has been demon-
wolf and birds of prey, the more bioaccumulative OCs,
strated at Alert and Tagish, as well as Dunai in the Rus-
in particular DDTs and PCBs, become more prevalent.
sian Arctic and at Bjørnøya in the European Arctic. The
elevated levels of PBDEs found at Alert and Tagish must
4.2.1. Soils and plants
be viewed with caution given that they are far higher
than levels found in the Great Lakes region, including
There has been a significant amount of new work on con-
within the city of Chicago, and higher than levels found
centrations of POPs in soils and plants since the previous
at Bjørnøya during winter time. The results for PBDEs
AMAP POPs assessment. Global surveys of PCDD/ Fs in
illustrate a general problem with all air sampling for
soils and tree bark by Wagrowski and Hites (2000), and
widely used products such as flame retardants, surfac-
PCBs in soils (Ockenden et al., 2002), have included
tants, and plasticizers (including chlorinated paraffins,
Arctic sites. An extensive survey of OCs in soil and
perfluorinated acids, and phthalates), which is that sam-
plants in Russia has also been carried out (RAIPON/
pling media or emissions from building materials or use
AMAP/GEF Project, 2001). This latter study is impor-
of materials near the site could inadvertently contami-
tant because the Russian Arctic was previously identified
nate the samples. Further work is urgently needed to
as a knowledge and data gap for assessment of circum-
confirm the levels of PBDEs in air given their increasing
polar trends of OCs. A project that examined levels of
presence in Arctic biota (Section 5.4.6.1).
OCs in vegetation and soil from Alaska and Siberia dur-
Toxaphene, a major contaminant in Arctic biota,
ing the years 1991-1993 (Ford et al., 2000) that was not
which has also been widely measured in Arctic seawater
available for the first AMAP report is also considered.
during the period of 1996-2001, remains relatively un-
studied in Arctic air. No new measurements have been
4.2.1.1. PCBs and OC pesticides in vegetation
reported from any of the monitoring stations. Given the
importance of this contaminant in both the North Am-
Samples of vegetation were collected from four regions
erican and European Arctic, additional data are needed
of the Russian Arctic: Kola Peninsula; Pechora Basin;
in order to examine levels and sources.
Taymir Peninsula (Dudinka and Khatanga); and, Chu-
The very limited data for PCBs and OC pesticides in
kotka (Kanchalan and Lavrentiya) in 2000/2001 for
snow and precipitation, with the exception of detailed
analysis of OCs (RAIPON/AMAP/GEF Project, 2001).
studies at Bjørnøya, illustrates a key knowledge gap
The four regions cover a wide geographical area (Figure
about the fate of airborne OCs. For example, the pro-
4 ·12). Pooled samples of three types of vegetation were
portion of the contaminants measured in air that is actu-
collected, including berries, lichens, and mosses; the
ally entering the snow or soil environment and then re-
species included for each type of vegetation varied with
volatilized is not known. A full understanding of the
the region (see Annex Table 4 for species). PCBs were
pathways is essential for predicting future trends and
the predominant OC in vegetation, followed by DDT,
also for evaluating other chemicals that have been de-
HCH, and chlorobenzenes. Toxaphene (sum of Parlars
tected in Arctic air.
26, 52, and 60; detection limits approximately 0.2 ng/g
The concentrations of PCBs in snow at Bjørnøya
in biota) and PBDEs (detection limits approximately 0.5
were similar to those in northern Norway (Enge et al.,
ng/g in biota) were not detected in any vegetation sam-
1998) and much higher than on the Lomonosovfonna
ples, but the detection limits of this study are above the
and Austfonna glaciers in Svalbard or at Summit, on the
levels normally found for these compounds in vegetation
Greenland Ice Cap. Air concentrations of PCBs were
in the Arctic.
also higher at Bjørnøya than at Ny-Ålesund. These re-
Across all regions, OC concentrations were greatest
sults suggest a strong influence of local biological sources
in mosses, followed by lichens and then berries, which
(e.g., seabird guano) on the POP patterns. This is a sur-
had very low concentrations. In general, strong geograph-
prising new finding which may also be the case on other
ical trends in OC concentrations were not observed be-
islands colonized by seabirds.
tween regions for any of the three vegetation groups
(Figure 4·12 and Annex Table 4). PCB concentrations
(3.1- 3.9 ng/g dw) in lichens are in the same range re-
4.2. Terrestrial environment
ported previously for lichens in the Russian Arctic, col-
Levels of OCs have been shown to be generally lower in
lected in 1994 (Melnikov et al., 1995), but are an order
the terrestrial Arctic ecosystem than in the aquatic eco-
of magnitude higher than levels reported for lichen from
system (de March et al., 1998). For this reason, the
the Canadian Arctic in 1992-1993 (de March et al.,
amount of research focused on, and the available data
1998). HCHs were the only OC group with higher con-
for, the terrestrial Arctic is much more limited, both his-
centrations in Canadian Arctic lichens compared to the
torically (see Thomas et al., 1992; de March et al., 1998)
Russian Arctic. The fact that the Canadian lichens were
and in recent years. A number of terrestrial mammals
collected in the early 1990s, and that HCH levels have
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
53
PCB concentration,
cides, industrial compounds, and PCB congeners (see
ng/g dw
Figure 4·13 for locations, and Annex Table 4 for species
5
4
names and concentrations) (Ford et al., 2000). Vegeta-
3
tion samples were primarily two species of ground-
2
1
dwelling lichens (Masonhalea richardsonii and Cetra-
0
Soil
ria cucullata) and two mosses (Racomitrium lanugi-
Mosses
Lichen
nosum and Hylocomium splendens). All four of these
Berries
species were collected in Alaska but only C. cucullata
was commonly found at the Russian study sites. Sam-
Lavrentiya Kanchalan
ples of other taxa, most notably blueberries (Vaccinium
uliginosum), were also taken opportunistically and pre-
dominantly in Alaska. Concentrations of OCs in li-
chens and mosses from all Alaskan and Russian loca-
tions were low (low ng/g dw) and in the range reported
Khatanga
for Russian lichens, mosses and berries recently col-
lected and discussed above (RAIPON/AMAP/GEF Pro-
Dudinka
ject, 2001), and previously for Arctic plants (de March
et al., 1998).
Analysis of the Alaskan data set demonstrated that
Nelmin Nos
concentrations for commonly encountered OCs were
Lovozero
generally highest in the lichen C. cucullata, followed by
the other lichens and mosses (Annex Table 4). This dif-
fers from the results of the recent Russian study where
the highest OC concentrations were found in mosses.
Concentrations of OCs in other Alaskan vegetation,
such as blueberries, were very low, and for many species
OCs were not detected, consistent with the Russian
Figure 4·12. Concentrations of PCBs in berries, lichens, mosses,
study. -HCH and PeCA were the individual OCs with
and soils from regions in Arctic Russia (RAIPON/AMAP/GEF Pro-
the highest concentrations;
4.2.1.1.1.
PCB concentrations were
ject, 2001). All samples are pools of numerous samples collected in
the highest among OC groups.
2000-2001. Species included in each vegetation group are given in
Annex Table 4.
OC concentrations in C. cucullata collected on the
Kola Peninsula/northern Urals (where sampling sites
decreased in the atmospheric environment may explain-
were close to industrial centers) were similar to those
part of this trend.
measured in the same species from Alaska and Taymir
In an older study, a total of 209 vegetation samples
(Figure 4·13). However, PCB concentrations in C. cucul-
(11 species across all sites) were collected from Alaska
lata from the Taymir Peninsula were approximately
and Russia in 1991-93 and analyzed for 51 OC pesti-
twice as high as those observed at other sites. This is
Concentration in lichen, ng/g dw
14
2.0
3.0
0.8
CB8
CB18
CB101
CB138
CB153
12
0.8
2.5
1.6
0.6
10
2.0
0.6
1.2
8
1.5
0.4
6
0.4
0.8
1.0
4
0.2
0.2
0.4
2
0.5
0
0
0
0
0
Alaska
Kola Taymir Urals
Alaska
Kola Taymir Urals
Alaska
Kola Taymir Urals
Alaska
Kola Taymir Urals
Alaska
Kola Taymir Urals
CB180
-HCH
HCB
1.2
9
5
4
7
Alaska
0.8
3
5
2
0.4
3
1
0
1
0
Taymir
Alaska
Kola Taymir Urals
Alaska
Kola Taymir Urals
Alaska
Kola Taymir Urals
16
Pentachloroanisole
-HCH
p,p'-DDE
3
0.5
Urals
12
0.4
2
0.3
8
Kola
0.2
1
4
0.1
0
0
0
Alaska
Kola Taymir Urals
Alaska
Kola Taymir Urals
Alaska
Kola Taymir Urals
Figure 4·13. Areas where lichens, mosses and soils were sampled in Alaska and Russia between 1991 and 1993, and concentrations of selected
OCs in lichen (Cetraria cucullata) from Alaskan and Russian locations (Ford et al., 2000).
54
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
due, in part, to much higher concentrations of lower
concentrations (27 congeners) in the 22 Arctic samples
chlorinated congeners, in particular CB8. Concentrations
ranged from 0.004 to 48 ng/g dw with highest concen-
of higher chlorinated congeners show less spatial differ-
trations in or near urban areas in northwestern Russia
ences, which is consistent with the recent Russian study
(Monchegorsk) and lowest concentrations in Greenland.
(RAIPON/AMAP/GEF Project, 2001).
After adjusting for soil organic matter (SOM), the range
Comparison of individual OC concentrations in C.
of concentrations was somewhat narrower (0.1-81 ng/g
cucullata from the Kola Peninsula/northern Urals, with
SOM). Ockenden et al. (2002) concluded that the SOM
regionally dispersed samples from Alaska and the
content and turnover governs PCB behavior because of
Taymir Peninsula, show a diversity of patterns (Figure
their strong affinity for organic carbon. Degradation of
4·13). Several analytes (aldrin, endrin, heptachlor and
POPs in soil is slow, of the order of tens of years (or
mirex) were not detected in Russian samples but spora-
more) for many compounds (Mackay et al., 2000). As
dically encountered in Alaskan samples. Lower chlo-
such, physical processes, bioturbation/ploughing, and
rinated PCBs (CBs 8 and 18) and semi-volatile OCs
carbon burial/sequestration in forest soils/peat become
( -HCH, HCB) were present in higher concentrations
key factors. These processes, together with physical oc-
on the Taymir Peninsula (Figure 4·13). Taymir is consid-
clusion/partitioning into the SOM (Luthy et al., 1997),
erably further north than the sites in the other regions
physically remove the bulk of the atmospherically-de-
and, this finding is consistent with the predicted global
rived POPs available for airsurface exchange by taking
fractionation of semi-volatile persistent organics (Wania
it below the all-important surface `skin' of soil which is
and Mackay, 1996). In contrast, higher chlorinated
in active exchange with the atmosphere (Harner et al.,
PCBs and several pesticides were present at higher con-
2001).
centrations in samples from Kola/Urals sites than in
those from Alaskan and Taymir sites (Figure 4·13). No
Russian and Alaskan soils
regional differences were evident for PeCA, cis-non-
Samples of surface soil were collected from four regions
achlor, and CBs 29, 187, and 206 (although outliers
of the Russian Arctic: Kola Peninsula; Pechora Basin;
were present for some of these analytes in a few Alaskan
Taymir Peninsula (Dudinka); and, Chukotka (Kancha-
samples).
lan and Lavrentiya), in 2000-2001 for the analysis of
OCs (RAIPON/AMAP/GEF Project, 2001). Samples
were collected in the same locations as plants and terres-
4.2.1.2. PCDD/Fs in tree bark
trial mammals, and covered a wide geographical area.
Tree bark was used by Wagrowski and Hites (2000) to
Each sample analyzed comprised a pool of the samples
study the global distribution of PCDD/Fs. The bark
collected. PCBs were the dominant OC measured in soils
samples (collected at 1 m height) were from locally im-
at all locations. Similar to results for vegetation from
portant tree species from sites in Alaska (1 site), Yu-
these regions, there were no strong geographical trends
kon/Northwest Territories (7 sites) and Norway (1 site),
in OC concentrations in Russian soils (Figure 4·12), and
along with samples from 54 other sites in the northern
OC concentrations were within a factor of two (Annex
and southern hemisphere. Concentrations of total
Table 4). A single soil sample from Lavrentiya in Chu-
PCDD/Fs in bark were low in the Arctic, ranging from
kotka had higher concentrations of PCBs (5.2 ± 3.5
not-detected (approximately 1 ng/g lw) to 685 pg/g lw
ng/g dw) but, since this is a single sample, caution is
with a median of 131 pg/g lw (Annex Table 4). No geo-
warranted about interpreting this as a hot spot. PCB
graphical differences were discernible among the Arctic
concentrations reported by the RAIPON/AMAP/GEF
samples. These concentrations were, however, at the low
Project (2001) were generally lower than reported by
end of the range found globally in tree bark from tem-
Ockenden et al. (2002); however, the latter soils were
perate zones (approximately 100 -227 000 pg/g lw).
generally collected close to urban areas while the former
Most tree bark samples from the Arctic were character-
study focused on background levels in remote areas.
ized by high proportions of tetrachlorodibenzofurans.
Concentrations of the OCs are in the range previously
Octachlorodibenzo-p-dioxin, which predominated in
reported for Russian soils (Melnikov et al., 1995). Toxa-
Arctic soils, was near detection limits in bark. This pat-
phene (sum of Parlars 26, 52 and 60, detection limits ap-
tern is consistent with the bark absorbing primarily
proximately 0.1 ng/g in soil) was not detected in any soil
lower chlorinated PCDD/Fs from the gas phase in areas
sample, but low concentrations (0.16 to 0.23 ng/g dw)
remote from major sources.
of PBDEs were observed in three soil samples.
In an earlier study, concentrations of OCs in the sur-
face soils of Alaska and Russia, collected between 1991
4.2.1.3. OC pesticides and PCBs in soils
and 1993, were low (low ng/g dw) (Annex Table 4)
Arctic soils in a global survey
(Ford et al., 2000) and in the range of levels reported for
Ockenden et al. (2002) conducted a global survey of
Arctic soil in the first AMAP assessment report (de
soils from rural and remote locations, which included
March et al., 1998). PCBs and DDTs were the pre-
22 sites in the Arctic (Canada, eastern Greenland, north-
dominant OCs found, with concentrations of CBz and
ern Norway, and northwestern Russia). Samples (0 -5
HCHs being similar to PCB and DDT concentra-
cm depth) were collected from 208 undisturbed sites
tions in the Alaskan soil only. PeCA, CB28, HCB, and -
throughout the world. Sites were more than 2 km from
HCH were among the more common individual OCs
the nearest town/city/busy road and more than 500 m
found. Concentrations were much higher in Alaska than
from small dwellings or tracks. The global latitudinal
on Kola and Taymir Peninsulas in Russia. However, the
distribution of PCBs in soils is plotted in Figure 2·4. The
Alaskan and Taymir samples included both surface veg-
Arctic soil results are presented in Annex Table 4. PCB
etation and litter, whereas Kola soils only included the
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
55
A-horizons (no vegetation or litter), making compar-
move appreciably from warm to cold latitudes. Most
isons with the Kola samples difficult. OC concentrations
Arctic soil samples were characterized by high propor-
in the Alaskan soils are similar, but the older Taymir
tions of octachlorodibenzo-p-dioxin, although tetra-
samples have much lower concentrations than the re-
chlorodibenzofurans were also important contributors
cently collected Russian soils (RAIPON/AMAP/GEF
to total PCDD/Fs.
Project, 2001). Differences in the collection methods and
Using the PCDD/F emission inventory for Canada
the organic content of the soils may explain some of the
and the U.S., Commoner et al. (2000) predicted `dioxin'
differences between the Russian data, but this informa-
TEQ deposition of about 4 -53 pg TEQ/m2/yr for terres-
tion is not currently available.
trial surfaces near eight communities in Nunavut. High-
Concentrations of individual OCs in the Kola Penin-
est deposition was predicted for the most southerly loca-
sula samples, which had no vegetation or litter, rarely
tion (Sanikiluaq, 53 TEQ/m2/yr). Eastern locations such
exceeded 1 ng/g dw. Due to the removal of vegetation
as Broughton Island (9 TEQ/m2/yr) had higher deposi-
and litter, it is not possible to compare these results with
tion than western locations (Ikaluktutiak, 4 TEQ/m2
recent results from Russian soil samples. Concentrations
year). Highest depositions were predicted to occur in the
of p,p'-DDT in Kola soils were one to two orders of
southern and eastern Arctic because of the preponder-
magnitude higher than most other analytes, suggesting
ance of dioxin sources in the eastern U.S. and Canada.
recent DDT use in this area at the time of collection
Russian and northern European sources were regarded
(1991-1993).
as insignificant in comparison to those in the mid-west
Specific information on A-horizon soils is not avail-
U.S., Ontario, and Quebec (Commoner et al., 2000).
able for Alaska and the Taymir Peninsula, although sev-
A direct comparison with the PCDD/F results from Wa-
eral soil cores from both those regions were taken.
growski and Hites (2000) was not possible because of
When A-horizon and 0-5 cm increment samples are col-
differences in geographical area and lack of data for spe-
lectively compared to the results for C. cucullata lichen,
cific 2,3,7,8-substituted PCDD/Fs in the soil survey.
some results were similar and some surprisingly dissimi-
lar. As with the lichen results, endrin, heptachlor, and
4.2.1.5. Simulation of the global fate of PCBs in soils
mirex were found only in Alaskan soils. Surprisingly,
concentrations of HCB, -HCH and CB18 were quite
The Globo-POP model has been used to describe the
low in the Taymir soil relative to the Kola and even
global fate of PCBs over a time scale of several decades
Alaskan soils, although concentrations of CB8 were
(Wania et al., 1999c; 2000). PCBs have been used
high. Concentrations of PeCA were high only in Taymir
as mixtures consisting of individual substances which
and Alaska, where they reached concentrations that ex-
differ substantially in their physical-chemical character-
ceeded those of most other analytes by one to two orders
istics and persistence. It is also likely that the temporal
of magnitude. Also as with the lichens, the Kola signals
and spatial pattern of release into the environment has
for p,p'-DDE and CBs 101 and 138 were high relative to
been different for different congeners (Breivik et al.,
Alaska and Taymir. Five of the six DDTs (except o,p'-
2002b). Large differences in the simulated fate of the
DDE), as well as CB153, were routinely found in Kola/
various PCB congeners reaffirm the need to perform cal-
Urals soils, but not in Alaska or Taymir soils.
culations for individual chemicals rather than chemical
Inorganic, cryogenically exposed surface soils were
mixtures. Thus, calculations were performed for a selec-
collected only in Alaska and the Taymir, and POPs con-
tion of congeners that vary in the number of chlorine
centrations rarely exceeded 1 ng/g dw in this matrix.
substitutions.
Where QA considerations permitted comparison, Alas-
One of the motivations for modeling PCBs globally is
kan samples of surface inorganic soils had higher ana-
to identify the major global-loss processes in order to as-
lyte concentrations than those from the Taymir, which is
sess the likely rate of future concentration decline in the
opposite to the pattern found for heavy metals and trace
Arctic environment and elsewhere (Wania et al., 1999c).
elements (Ford et al., 2002).
The model calculations showed that, historically, atmos-
pheric degradation and transfer to the deep sea con-
tributed most to the loss of PCBs from the global envi-
4.2.1.4. PCDD/Fs in Arctic soils
ronment, whereas burial in freshwater sediments was of
As part of a global survey of PCDD/Fs in soils and tree
little significance on a global scale. Reaction of the
bark, Wagrowski and Hites (2000) reported PCDD/Fs
gaseous compounds with OH radicals is the loss pro-
in soils from Alaska, the Yukon and NWT in the Cana-
cess of primary importance for the lighter congeners,
dian Arctic, western Greenland, and Norway. For this
whereas the deep-sea transfer process increases in rele-
assessment, these data were combined with results from
vance with the degree of chlorination. The model further
Brzuzy and Hites (1996) who conducted an earlier,
predicts that the relative importance of the various loss
smaller-scale soil survey that included samples in Alaska
processes has been changing over time, with degradation
and northwestern Russia (Annex Table 4). Fluxes of
in soils taking over as the major loss process in the past
total PCDD/Fs estimated from the mass of chemicals
twenty years. As primary emissions decreased, the con-
in a 10 10 cm (15 cm depth) core ranged from 1.2 to
centrations (and thus, loss rates) of PCBs in the atmos-
143 ng/m2/yr. There was no consistent geographical
phere and ocean water have declined quickly, whereas
trend in the 12 samples; however, higher fluxes were
soils have retained a high pollutant load due to their
seen in samples from Alaska and western Greenland. By
slow response time (large capacity, but slow evaporation
comparison, the range of fluxes of total PCDD/Fs for
and degradation). Unfortunately, this implies that the fu-
sites in the mid-latitudes and tropics was 5-8100
ture rate of purification of the global environment will
ng/m2/yr. The authors concluded that PCDD/Fs did not
be determined by the slow and poorly quantified degra-
56
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
PCB homologue composition in soil, %
100
HeptaCBs
OctaCBs
1970
2000
HexaCBs
75
PentaCBs
50
TetraCBs
25
TriCBs
DiCBs
0
N-Polar
Boreal
N-Temperate
N-Subtropic
N-Tropic N-Polar
Boreal
N-Temperate
N-Subtropic
N-Tropic
Circumpolar region
Circumpolar region
Figure 4·14. Modeled PCB homologue composition in soil in 1970 and 2000 in different zones of the northern hemi-
sphere. The model predicts a shift to increasingly more volatile homologues with increasing latitude, and increased im-
portance of the less volatile homologues over time, as the lighter homologues are more readily degraded (Wania, 1999).
dation rate in the soil environment. Figure 4·14 shows
paigns (Muir et al., 1996a; Ockenden et al., 1998;
the homologue composition of PCBs in soil in 1970 and
2002). The model further suggests that these shifts differ
2000 predicted by the Globo-POP model. The composi-
between various environmental media, change over time
tion shifts to increasingly more volatile homologues with
and are rather complex.
increasing latitude. In the past thirty years of steadily de-
clining PCB emissions, the less volatile congeners have
4.2.2. Terrestrial herbivores
increased in relative importance as the lighter homolo-
gues are degraded more readily.
The previous AMAP assessment reported a large amount
The global distribution model can also be used to in-
of OC data on caribou/reindeer (Rangifer tarandus).
vestigate compositional shifts among the PCB congeners
This species is an important food item in most northern
between compartments, zones and different time peri-
societies and represents an excellent species to monitor
ods. Due to their wide range of physical-chemical prop-
terrestrial contamination, due to their diet of plants and
erties, PCBs have played an important role in the deriva-
lichen. Geographical differences were observed previ-
tion of the concept of global fractionation, which results
ously in OC concentrations in caribou/reindeer (de
in compositional shifts of compound mixtures with lati-
March et al., 1998) but, in general, levels were low com-
tude (Wania and Mackay, 1993; 1996). The model suc-
pared to Arctic marine mammals. For this reason, there
ceeded in reproducing observed shifts toward lighter
are few new data on OC levels in caribou/reindeer and
(lower chlorinated) PCB congeners with increasing lati-
studies of terrestrial species have mainly focused on con-
tude (Figure 4·15) found in various measurement cam-
centrations of radionuclides and heavy metals. Since
1997, there have been new studies on OCs in terrestrial
PCB homologue concentration in soil,
mammals from Greenland (Muir and Johansen, 2001),
normalized to global average
Faroe Islands (Larsen and Dam, 1999) and Russia
8
(RAIPON/AMAP/GEF Project, 2001), and a study on
DiCBs
OC levels in reindeer from Finland (Hirvi and Hentto-
nen, 2002).
6
TriCBs
Russian terrestrial herbivores
TetraCBs
OC analyses were conducted on samples of various tis-
4
sues (kidney, liver, and muscle) from four species of ter-
PentaCBs
restrial herbivores (reindeer, mountain hare (Lepus timi-
HexaCBs
dus), ptarmigan (Lagopus mutus), and willow grouse
2 HeptaCBs
(Lagopus lagopus)) collected in 2000-2001 from four re-
OctaCBs
gions of the Russian Arctic: Kola Peninsula (Lovozero);
Pechora Basin (Nelmin Nos); the Taymir Peninsula (Du-
0
dinka and Khatanga); and, Chukotka (Kanchalan and
N-Polar
Boreal
N-Temperate N-Subtropic
N-Tropic
Lavrentiya) (RAIPON/AMAP/GEF Project, 2001). Sam-
Figure 4·15. Soil concentrations of various PCB homologues as a
ples were collected in the same regions as the vegetation
function of (northern hemisphere) climate zone for the year 2000,
and soil samples (see Sections 4.2.1.1 and 4.2.1.3).
predicted using the `Globo-POPs' model of Wania and Mackay
Across all species, OC concentrations were highest in
4.2.1.4.2
(2000). The soil concentrations are normalized to the global aver-
liver followed by kidney and muscle, which is likely due
age concentration of a particular homologue. The concentrations of
the lighter homologues, with up to four chlorines, increase steadily
to higher lipid content of the liver, although no lipid data
with latitude.
are currently available for these samples. Across all re-
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
57
PCB concentration in liver,
discussed above). Liver concentrations were higher than
ng/g ww
muscle for PCDDs, PCDFs, and TEQs and PCDFs
0.5
were greater than PCDDs. Concentrations of PCDDs,
0.4
PCDFs, and TEQ were generally below 0.5 pg/g ww,
0.3
with the exception of reindeer liver from the western
0.2
sites Kola Peninsula (6.5 pg/g ww), Pechora Basin (2.5
0.1
pg/g ww), and the Taymir Peninsula (0.7 pg/g ww).
0
These locations are downwind of large cities (Mur-
Reindeer
Hare
mansk, Monchegorsk, Norilsk) which have non-ferrous
Ptarmigan
smelters, a known source of airborne PCDFs.
No sample
analyzed
Greenland terrestrial herbivores
Levels of OCs were assessed in a variety of tissues
(liver, kidney, muscle, and fat) of terrestrial mammals
(mountain hare, domestic lambs (Ovis spp.), and musk-
ox (Ovibos moschatus)), and ptarmigan of Greenland
Lavrentiya
(Annex Table 5). These species are important foodstuffs
Kanchalan
(Muir and Johansen, 2001). PCBs (concentration range
of 0.5-7.5 ng/g ww) were by far the predominant OCs in
all species across all tissues. The ranking of the other
OCs varied with the tissue, but, in general, DDT and
chlordanes were the next most common OC. Wet weight
Khatanga
concentrations were greatest in fat, but lipid-corrected
Dudinka
concentrations were often highest in liver or kidney. OC
concentrations were similar between species, reflecting
similar diets. These concentrations are in the range re-
Qeqertarsuaq
Nelmin Nos
ported previously for herbivorous terrestrial mammals
Nuuk
from the Canadian and European Arctic, but are orders
Lovozero
of magnitude less than those observed in marine mam-
mals such as the ringed seal (de March et al., 1998).
Faroe
Compared to the Russian data, PCB concentrations in
Islands
hares are similar (Figure 4·16) but ptarmigan have much
higher concentrations. Interestingly, concentrations of
chlorobenzenes observed in these terrestrial samples are
Figure 4·16. Concentrations of PCBs in reindeer, Arctic hare and
similar to those in marine mammals.
ptarmigans/willow grouse from regions within Russia (RAIPON/
AMAP/GEF Pr
4 2 2 1
oject, 2001), and from Greenland and the Faroe Is-
Faroe Islands herbivores
lands. Bars are means (with ± 1 SE indicated when more than two
Levels of OCs were determined in Faroe Islands terres-
pooled samples are available). All samples are pools of numerous
trial mammals, sheep, and mountain hare, which are
samples collected in 2000-2001.
part of the human diet (Larsen and Dam, 1999). In hare
gions and OC groups, OC concentrations were similar
liver (n = 13), the predominant OCs were HCB and oxy-
in the reindeer, ptarmigan, and willow grouse but lower
chlordane, both occurring at mean concentrations near
in the mountain hares (Figure 4·16 and Annex Table 5).
30 ng/g lw. The concentrations of HCB are similar to
Some geographical trends were found. OC concentra-
those found in sculpin from the Faroe Islands, but are
tions were higher in the regions of Lovozero (Kola
one fifth of those detected in other marine species such
Peninsula) and Nelmin Nos (Pechora Basin), but for
as black guillemot eggs and pilot whale tissues. The con-
each species, OC concentrations were within a factor of
centration of PCB (as CB153) was low and near the de-
four across all regions. OC concentrations in these Russ-
tection limit (approximately 4 ng/g lw), and other con-
ian terrestrial herbivores are in the same range as those
geners were rarely detected. Of the six DDT isomers,
observed recently in Greenland terrestrial herbivorous
only p,p'-DDE was regularly detected with a mean con-
mammals (Muir and Johansen, 2001), and reported for
centration of 7 ng/g lw. Toxaphene, mirex, and the other
Russian reindeer collected in 1994 (Melnikov et al.,
chlordanes were normally not detected. Liver and tallow
1995). Toxaphene (sum of Parlars 26, 52 and 60; detec-
taken from around the kidney of eight sheep and 17
tion limits approximately 0.2 ng/g in biota) and PBDEs
lambs at each site were sampled from two locations in
(detection limits approximately 0.5 ng/g in biota) were
1997. In most cases, PCB congeners, chlordanes, toxa-
not detected in any terrestrial herbivore samples, but the
phene, and p,p'-DDT were not detected. In lamb and
detection limits of this study are above the levels nor-
sheep liver, the concentration of CB153 and CB138 were
mally found for these compounds in Arctic biota.
approximately 5 ng/g lw and 2 ng/g lw, respectively, with
Concentrations of PCDDs, PCDFs, and TEQs
slightly lower concentrations in tallow, especially in
were reported for muscle of reindeer, hares, ptarmigan
sheep. The concentrations of p,p'-DDE in sheep and
and willow grouse collected in 2000-2001 from four re-
lamb liver were approximately 6 ng/g lw and 3 ng/g lw,
gions of the Russian Arctic (RAIPON/AMAP/GEF Pro-
respectively. Concentrations of OCs in the Faroe Islands
ject, 2001) (Annex Table 16). Liver was also analyzed in
terrestrial herbivores are similar to values reported in
reindeer and hares (the same samples analyzed for OCs,
similar species from Greenland.
58
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Finland reindeer
way, including northern parts, during the period 1991-
OCs were found to be very low in the fat of reindeer col-
1997 and analyzed for OCs, including toxaphene (Herz-
lected in northern Finland in 2000, with most OCs be-
ke et al., 2002). The DDT-transformation product p,p'-
low the detection limits (< 5 ng/g) (Hirvi and Hentonen,
DDE still dominates the pesticide burden in all preda-
2002). However, these detection limits are high and
tory bird eggs (70 -90% of the pesticide burden) 30
above OC levels normally seen in Arctic terrestrial ani-
years after the ban of these chemicals in western coun-
mals (Annex Table 5). Chlorobenzenes were found at
tries. PCBs accounted for 70 -80% of the total OC bur-
the highest concentration (CBz 14.3±4.4 ng/g ww),
den in predatory birds, confirming the high ecotoxico-
followed by DDTs (6.1±1.9 ng/g ww) and PCBs
logical potential of this type of contaminant for birds of
(3.5 ± 8.8 ng/g ww). These concentrations are at the low
prey. The highest average concentrations for PCBs were
end of those reported previously for Arctic caribou/rein-
found in eggs from white-tailed sea eagle (Haliaeetus al-
deer (de March et al., 1998). High levels of chloroben-
bicilla) and peregrine falcon (average PCB concentra-
zenes, relative to other OCs, are often found in cari-
tion: 8.9 µg/g ww and 9.1 µg/g ww, respectively). Merlin
bou/reindeer (de March et al., 1998).
(Falco columbarius) and sparrowhawk (Accipiter nisus)
eggs had the highest concentrations of chlorinated pesti-
cides (average sum pesticide concentration: 3.0 µg/g ww
4.2.3. Birds of prey
and 4.3 µg/g ww, respectively). Toxaphenes were deter-
Birds of prey have been of particular importance in the
mined, and concentrations were low compared to PCBs
study of OCs in the Arctic due to their susceptibility to the
and OCs. The highest toxaphene levels were found for
effects of OCs and the potential for accumulation of OCs
bird species feeding on fish or migratory passerines. The
from winter habitats. A number of species were examined
highest toxaphene concentration was found in white-
in the past (see de March et al., 1998) but most recent
tailed sea eagle eggs (0.09 µg/g ww). No toxaphene was
work has focused on peregrine falcons (Falco peregrinus).
found in osprey (Pandion haliaetus) and merlin eggs. No
spatial or regional specific trends or patterns in OCs
were found for the egg samples analyzed.
4.2.3.1. North American peregrine falcon
Osprey, merlin, sparrowhawk and peregrine falcon
Subspecies in Alaska are: the Arctic peregrine (F. p. tun-
migrate to southern winter habitats where many pesti-
drius), which nest in northern tundra; the American per-
cides are in use, and feed on local prey available in these
egrine (F. p. anatum), which nests in the forested inte-
regions. Gyrfalcon (Falco rusticolus), goshawk (Accip-
rior; and, the Peale's peregrine (F. p. pealei), which nests
iter gentiles), golden eagle (Aquila chrysaetos), and
along the southern coast from the Aleutian Islands to
white-tailed sea eagle are usually more confined to a
southeast Alaska.
specific habitat, and not as apt to migrate. The high pes-
Persistent OC contaminants were measured in Amer-
ticide levels found in merlin, sparrowhawk, and pere-
ican and Arctic peregrine falcon eggs from Alaska during
grine falcon may thus, in part, be explained by their mi-
the period of 1979-1995 (Ambrose et al., 2000) (Annex
gratory habits.
Table 5). This dataset was not included in the first AMAP
POPs assessment, and a more detailed discussion of the
4.2.3.3. `New' chemicals in European Arctic birds of prey
data is provided in the temporal trends section (Section
5.2). Dieldrin, p,p'-DDE, heptachlor epoxide, oxychlor-
High PBDE concentrations have been found in preda-
dane, mirex, and total (Aroclor) PCBs were consistently
tory birds feeding on terrestrial mammals and birds,
detected and measured in all samples. HCB, p,p'-dichlo-
particularly peregrine falcons in northern Sweden (Sell-
rodiphenyldichloroethane (DDD), p,p'-DDT, -HCH,
ström et al., 2001; Lindberg et al., 2004) and Norway
and trans-nonachlor were detected in more than 50% of
(Herzke et al., 2001a). The mean PBDEs (BDEs 47, 99,
samples, and -HCH, -HCH, trans-chlordane, cis-chlor-
100, 153, and 154) in the two populations are 224 and
dane, o,p'-DDD, o,p'-DDE, o,p'-DDT, endosulfan II,
260 ng/g ww (4500 and 4700 ng/g lw), respectively, with
and endrin were detected in less than 50% of samples.
levels ranging from 43 to 1580 ng/g ww (680 -39000
ng/g lw) in the Swedish population. The PBDE levels in
Norwegian golden eagles, gyrfalcons, and merlins were
4.2.3.2. European Arctic birds of prey
7, 18, and 36 ng/g ww (approximately 140, 360, and
To assess the current level of OCs in Arctic European
720 ng/g lw). The congener pattern in all these bird
birds of prey, 44 egg samples from eight different raptor
species is quite different from that seen in fish and fish-
species (Table 4 ·6) were collected from throughout Nor-
eating birds and mammals, dominated by BDE153 and
Table 4·6. Habitat and diet information for Norwegian bird of prey species from which
eggs were collected between 1991 and 1997 for OC analyses (Herzke et al., 2002).
Species
Habitat description
Main food objects
Merlin
Terrestrial
Passerines and waders
White-tailed sea eagle
Marine
Fish and seabirds
Goshawk
Terrestrial
Medium-sized birds, small mammals
Golden eagle
Terrestrial
Mammals and game birds
Peregrine falcon
Terrestrial/marine
Medium-sized birds
Osprey
Limnic
Freshwater fish
Gyrfalcon
Terrestrial
Medium-sized birds
Sparrowhawk
Terrestrial
Passerines
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
59
99. The Swedish peregrine falcons also had measurable
The most abundant OC analytes detected in wolverine
levels of BDE183 (HpBDE) and BDE209 (DeBDE).
liver (in order from highest to lowest) were CB153,
PBDE levels are only 3-4 times less than PCB levels in
CB180, oxychlordane, CB138, p,p'-DDE, CBs 170/190,
Swedish peregrine falcons. HBCD concentrations ranged
CB99, CB118, and dieldrin. These OCs are among the
from 2.2 to 28 ng/g ww (34-2400 ng/g lw) in the Swe-
most recalcitrant and are also the predominant OCs in
dish peregrine falcons. The burden of PBDEs in pere-
other terrestrial Arctic mammalian predators, such as
grine falcons may be linked to their migratory habits as
wolves (Gamberg and Braune 1999). Wolverine age and
the northern population in Sweden overwinters along
sex did not influence OC concentrations.
the coast and estuaries of central and southern Europe.
Levels of chlordane and HCHs were much lower in
In addition, many of the birds that they prey on when in
the wolverines compared to the Arctic fox collected to
the Arctic are also migratory and may have PBDE bur-
the north in Ulukhaqtuuq (Hoekstra et al., 2002a) but
dens from their overwintering sites further south.
are in the range of levels in other Arctic terrestrial mam-
mals. This was expected because coastal populations of
Arctic fox are known to scavenge marine mammals, re-
4.2.4. Other carnivores
sulting in elevated OCs (Klobes et al., 1998a). However,
There are a number of terrestrial mammalian carnivores
levels of PCBs and DDTs were similar or higher in the
in the Arctic including the mink, wolf (Canis lupus), and
wolverine compared to the Arctic fox. Concentrations of
wolverine (Gulo gulo). The Arctic fox is often consid-
these OCs in the wolverine are much higher than other
ered a terrestrial carnivore but has been included in the
Arctic terrestrial mammals (Annex Table 5). Although
marine mammal section of this report (Section 4.4.8).
these PCB and DDT levels are below most threshold ef-
Through the process of biomagnification, these organ-
fects levels (Hoekstra et al., 2002a) an explanation for
isms generally have higher concentrations of OCs than
these unexpected high levels is not evident and merits
terrestrial herbivores (de March et al., 1998). However,
further research.
the generally lower levels of OCs in the Arctic terrestrial
environment results in OC concentrations in terrestrial
Common shrew
carnivores that are much lower than in their marine
OCs were measured in the common shrew (Sorex ara-
counterparts. Some terrestrial mammals (e.g., the wolf)
neus) liver collected in 1999 and 2000 in the area of Pal-
are also considered to have more efficient biotransfor-
las, northern Finland (Hirvi and Henttonen, 2002). This
mation ability based on the very small numbers of PCB
small mammal feeds on insects, worms, and other simi-
congeners found in their tissues (Gamberg and Braune,
lar small animals. The mean levels of OC pesticides in
1999; Shore et al., 2001). There have been few studies
immature shrews were 0.2-13.0 ng/g ww and in adults
on OCs in terrestrial carnivores since the original AMAP
0.5 -25.0 ng/g ww, which are similar but slightly higher
report, in part because of low concern based on low lev-
than levels observed in reindeer from the same region of
els in the terrestrial Arctic environment, and because few
Finland. PCB concentrations were 0.3-5.0 ng/g ww.
terrestrial carnivores are included in the diet of humans.
The highest levels were measured for oxychlordane fol-
lowed by -HCH, -HCH and trans-nonachlor. The
Wolves
concentrations of these contaminants were 10 -20 times
There have been two studies on OC levels and patterns
higher in shrews than in the humus layers, reflecting bio-
in wolves collected in the subarctic and Arctic in the past
magnification up this short food web.
five years. Levels of OCs were measured in the liver of
58 wolves collected in northwest Russia (Shore et al.,
4.2.5. Summary and conclusions
2001) and in the liver of wolves collected in the Cana-
terrestrial environment
dian Yukon (Gamberg and Braune, 1999). Both studies
found concentrations to be very low (mean or median
The first AMAP POPs assessment concluded that there
below 50 ng/g ww) but were slightly higher in the Rus-
had been a significant amount of research on OC levels in
sian wolves (Annex Table 5). For many samples, com-
the Arctic terrestrial environment, although it found that
mon OCs, such as p,p'-DDE, were not detected, likely
there was insufficient spatial coverage of media other
due to a combination of low levels and efficient bio-
than in caribou and reindeer (de March et al., 1998).
transformation. A small number of highly chlorinated
Since that report (1997 to 2001), studies on the global
PCB congeners dominated the PCB load in both studies.
distribution of PCBs and PCDD/Fs in soils have included
OC concentrations were not found to vary between
sites in the Arctic, thus providing a much clearer per-
sexes and, with the exception of PCBs, did not vary with
spective of the levels of these contaminants in Arctic
age. Both studies concluded that the levels of OCs do
soils. With the exception of work in Russia, these studies
not pose a threat to the health of wolf populations.
were not conducted as part of the AMAP implementa-
tion programs of various circumpolar countries. While
Wolverines
the global survey results show that levels of PCBs and
Wolverines are omnivorous terrestrial mammals that live
PCDD/Fs are much lower in the Arctic than in the north-
throughout the alpine and Arctic tundra of Canada and
ern temperate zone, there are urban areas within the
Scandinavia. Livers from 12 wolverines were collected at
Arctic, especially in Russia, with elevated PCB levels.
Kugluktuk, Nunavut, in the western Canadian Arctic to
The results of global modeling and soil measurements of
determine, for the first time, the residue patterns of OCs
PCBs imply that the future rate of purification of the
in this species (Hoekstra et al., 2002a). The ranking of
global environment will be determined by the slow and
hepatic concentrations for sum () OC groups in wolver-
poorly quantified degradation rate in the soil environ-
ines was PCBs > CHLs > DDTs > HCHs > CBz.
ment. Thus, despite low levels, future surveys of Arctic
60
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
soils will be important for tracking long-term trends in
that `With the exception of river and lake waters, the
the elimination of PCBs and related POPs.
original minimum monitoring objectives of AMAP for
The limited amount of research that has been carried
POPs in freshwater matrices have been met in all cir-
out in the terrestrial Arctic confirms what was reported
cumpolar countries.' The freshwater ecosystems of the
in the first AMAP POPs assessment. It is apparent that
Arctic are contaminated almost exclusively by atmos-
Arctic terrestrial biota, with the exception of predatory
pherically transported POPs. There are exceptions to
birds and animals near local sources, have among the
this, such as rivers and the systems fed by these rivers,
lowest OC concentrations of any biota in the world.
which flow through northern cities and/or drain more
Concentrations of OCs in this environment are orders of
southerly agricultural watersheds.
magnitude less than what is observed in the freshwater
OC concentrations in Russian Arctic river waters
and marine environments. In soil and lower trophic-level
collected in the mid-1990s were found to be approxi-
organisms, HCB and HCHs are the most prevalent OCs,
mately ten times higher than levels observed in Canada
but PCBs, chlordane, and DDTs become more prevalent
and Norway (de March et al., 1998). These results were
at higher trophic levels. CBz concentrations in cari-
originally questioned but have since been verified as dis-
bou/reindeer are similar to PCBs and DDTs.
cussed in Section 4.3.1. There were insufficient data to
The extensive spatial survey of OCs in soil, vegetation
examine circumpolar trends of POPs in freshwaters in
and terrestrial herbivores carried out very recently in the
detail in the first AMAP assessment report. There was
Russian Arctic (2000 and 2001), provided data that fill
however moderately comprehensive coverage for surface
a knowledge gap identified in the first AMAP POPs as-
sediments. With the exception of PCB concentrations
sessment (de March et al., 1998). PCB concentrations
in water from a few Canadian lakes, levels of OCs in
were the highest of any OC group, followed by DDTs
water and sediment did not exceed guideline levels for
and HCHs. Toxaphene and PBDEs were rarely de-
protecting aquatic wildlife (de March et al., 1998) (see
tected and only in soil; however, the detection limits in
also Table 6.1). OC levels in freshwater biota were
this study are above the levels normally found for these
found to be higher than in terrestrial biota, but lower
compounds in the Arctic. This survey found that there
than in comparable trophic levels of marine biota (de
were minor geographical trends in OC concentrations
March et al., 1998). Good circumpolar coverage of OCs
across Russia in the terrestrial environment, although
was available for Arctic char, which showed similar lev-
slightly elevated levels of OCs were observed in terres-
els throughout the Arctic except in lakes where some
trial herbivores from two regions and PCDD/F concen-
char had become cannibalistic. PCBs were the most com-
trations were high in reindeer in areas near smelters. The
mon OC group, although toxaphene was shown to be a
concentrations found were similar to those found in
major OC in Canadian freshwater biota.
Russian Arctic samples collected in the mid-1990s and
Since the first AMAP POPs assessment, there have
in Greenland terrestrial herbivorous mammals, but were
been a number of studies on POPs (specifically PCBs and
slightly higher than those observed in older Canadian
OC pesticides) in the freshwater environment, but the
Arctic terrestrial studies. There have been no recent
amount of data produced is small compared to that pro-
studies on OCs in terrestrial herbivores in the Canadian
duced for the marine environment. As with the terres-
or Alaskan Arctic. Two independent studies on wolves
trial environment, concentrations of OC contaminants
in Canada and Russia found similar levels of OCs.
are relatively low in most freshwater biota. Neverthe-
Contamination of the terrestrial environment by
less, studies of OCs in freshwater fish in Alaska, Can-
OCs appears to be close to uniform across the circum-
ada, Greenland, and Russia have continued, in part be-
polar Arctic, with slightly lower (2-3 times) concentra-
cause they are important dietary items. Extensive studies
tions in Canada. Lower OC concentrations in the Cana-
on OCs in the food webs of Bjørnøya have also been car-
dian terrestrial Arctic conform to spatial trends of OCs
ried out, and long-term temporal trends studies of fresh-
observed in Arctic air and aquatic biota. However, there
water fish in Sweden have continued (Section 5.3.2).
has been no recent extensive circumpolar survey of OCs
in any one matrix or biota species and therefore, conclu-
4.3.1. Concentrations and loadings in surface waters
sions about spatial trends of OCs in the terrestrial Arctic
are difficult and should be made with caution. Although
4.3.1.1. Verification of older Russian river water data
this represents a knowledge gap, the generally low OC
Background
levels found in the Arctic terrestrial environment indi-
The previous AMAP POPs assessment compared con-
cate that this not a major issue.
centrations of the OC pesticides HCH and DDT in
High levels of PBDEs were found in Arctic terres-
major north-flowing rivers in Russia to results from
trial-feeding birds of prey. Congener patterns were quite
Canada and Norway from sampling and analysis cam-
different from those observed in biota feeding within the
paigns conducted in the mid-1990s. In the past five
aquatic environment. There is very little data for other
years, there have been no new studies of POPs in river
`new' chemicals, such as PFOS, in the terrestrial environ-
waters in the Canadian Arctic, northern Norway or in
ment. There is a need to assess the levels and spatial
northern Russia. A project was conducted in Russia in
trends of `new' chemicals, particularly in birds of prey.
2001-2002 to study contaminants in the Yenisey and
Pechora rivers (RAIPON/AMAP/GEF Project, 2001),
however the results were not available in time for this
4.3. Freshwater environment
assessment. The data from Russian rivers reported in de
A fairly substantial dataset on OCs in Arctic freshwater
March et al. (1998) were received late in the assessment
ecosystems was summarized in the first AMAP POPs as-
process and not thoroughly evaluated. Since then, sev-
sessment (de March et al., 1998). That report concluded
eral papers have been published which give a more com-
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
61
prehensive description of the quality assurance program
Table 4·7. Seven-year weighted mean concentrations ( g/L) of con-
followed, as well as the levels and trends of OC pesti-
taminants in Russian northern rivers: 1990-1996 a.
cides in major Russian rivers (Zhulidov et al., 1998;
River
-HCH
-HCH
p,p'-DDT
p,p'-DDE
Alexeeva et al., 2001). Therefore, the available results
are re-examined here. Zhulidov et al. (2002) have also
Kola
0.003
0.003
< 0.001
< 0.001
reported temporal trends of HCH and DDT isomers
Onega
0.003
0.003
< 0.001
< 0.001
from the late 1980s to early 1990s in major rivers and
Sev. Dvina
0.001
0.001
< 0.001
< 0.001
these are discussed in Section 5.3.1.
Mezen
0.004
0.004
0.004
< 0.001
All sampling and analyses of POPs in Russian rivers
Pechora
0.002
0.012
0.001
0.001
Ob
0.030
0.053
0.020
0.002
during the period 1990-1996 were carried out by re-
Nadym
0.029
0.065
0.020
0.007
gional laboratories of ROSHYDROMET (Federal Ser-
Pur
0.069
0.107
0.027
0.006
vice of Russia on Hydrometeorology and Environment)
Taz
0.058
0.114
0.038
< 0.001
with method development and quality assurance carried
Yenisey
0.009
0.016
< 0.001
< 0.001
out by a central co-ordinator (the Hydrochemical Insti-
Anabar
< 0.001
< 0.001
< 0.001
< 0.001
Olenek
0.001
< 0.001
< 0.001
< 0.001
tute, located in Rostov-on-Don). Methods used for the
Lena
< 0.001
0.001
< 0.001
0.008
OC pesticides involved solvent extraction (hexane) of
Kolyma
< 0.001
0.003
< 0.001
< 0.001
1 L of unfiltered water and gas chromatographic deter-
mination. An improved clean-up method involving H
a
2SO4
Weighted average calculated for all data for the study period,
became available in 1995 and was in use in 1996 in all
weighted for the number of contributing samples for each annual
mean.
UGMS labs. The internal UGMS results for both preci-
sion and accuracy for all contaminants were very good
Comparability of OC pesticide concentrations for
(< 30% deviation) for the six OC compounds deter-
the rivers Ob, Yenisey, Lena, and Kolyma were assessed
mined. These six compounds were -HCH, -HCH,
by Alexeeva et al. (2001) using independent data re-
-HCH, p,p'-DDE, p,p'-DDT, and dihydroheptachlor
ported by Zhulidov et al. (1998). The mid-range of the
(DHH; a heptachlor analog not determined in European
data from the `independent specialists' part of that re-
or North American studies of OC pesticides).
port was employed for comparison since means were
not presented. The mid-range values from the independ-
Sampling program
ent specialists and the concentration means in this sec-
Sampling took place at stations along major Russian
tion (Table 4·7) gave inconsistent ratios. In the Ob, val-
rivers that are tributaries to the Arctic Ocean. Most at-
ues from the specialists were 3-6 times higher than those
tention was focused on the stations located further
reported by UGMS laboratories for both -HCH and -
downstream in each large river in order to estimate load-
HCH; for the Yenisey, the concentrations given in both
ings to the Arctic Ocean. Some of the stations were sev-
reports were similar (within 20%), while levels for the
eral hundred kilometers upstream of the geographical
Lena and Kolyma were below those of the specialists.
river mouth, as defined by headlands on the mainland.
In some cases, this was because the tidal/saline charac-
OC pesticide levels and spatial trends
teristics of the river extend many kilometers upstream;
The available concentration data were limited to annual
in others, it was a matter of logistical convenience for
arithmetic means, ranges, and the number of samples
sample collection. In some cases, there are cities with
(log normal distributions were reported for the larger
significant populations located upstream of the river
data sets). This data set for 15 rivers and six regularly
mouth monitoring stations. Such cities and rivers in-
monitored OC contaminants over seven years, was ex-
clude: Onega on the Onega River; Novodvinsk and
amined for each river to assess whether temporal or geo-
Archangelsk on the Severnaya Dvina River; Naryan-Mar
graphic pattern(s) existed. A significant temporal trend
on the Pechora river; and, Dudinka on the Yenisey River.
was apparent only for -HCH concentrations in the Pe-
Estimation of OC pesticide loadings was made diffi-
chora River (1990 -1996), but not for any other pesti-
cult by the presence of many non-detect (nd) values.
cide or river. In the case of -HCH in the Pechora, the
This does not mean that the OCs were not present, only
origin of the contaminant must be relatively local be-
that they were less than the detection limit. In the data
cause similar patterns were not observed in other nearby
sets evaluated, a zero was substituted for `nd' for spread-
rivers. There has, however, been no reported agricultural
sheet purposes whenever, e.g., the mean for an analyte
use of -HCH in this basin during the years reported. It
was calculated. This biases the mean result toward a low
may be that the source is from urban waste waters due
value; however, substitution of the detection limit would
to domestic uses in towns and cities within the water-
bias the results toward a high value. During examina-
shed, or from use for biting-fly control in urban and
tion of the data, it was seen that an occasional maxi-
other non-agricultural settings. As a consequence of
mum value (outlier) represented the determining value in
there being no consistent temporal patterns, the concen-
the mean, usually when there were only a small number
tration data for the rivers were averaged for the study
of data points. Where a reason to reject such points was
period, and weighted for the number of contributing
determined by the group responsible for this study, the
samples for each annual mean (Table 4·7)
mean was recalculated; where there was no reason for
The -HCH and -HCH concentrations in the rivers
rejection, the data were included. All data presented
draining into the White/Barents Seas (Table 4·7) were in
have been `vetted' in this manner. The extent of the `nd'
the low µg/L range (means 0.0023 and 0.0041 µg/L, re-
values in the data reported in their study is unknown,
spectively). DDT and DDE were non-detectable except
but it is believed to be extensive so the means and load-
for the Pechora in 1993 and 1996. Even the maximum
ings presented here are considered conservative.
contaminant levels for the rivers do not appear to change
62
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
in any consistent fashion over the reporting period.
There were few observations of OC pesticides above
-HCH in the Pechora seemed to display higher mean
the detection limits for any of the rivers flowing into
and maximum levels in the 1990-1994 time period, but
the Laptev and East Siberian Seas (only for HCHs;
these were only 2-3 times those found elsewhere in the
mainly in 1990). This part of Russia is characterized by
same region. DDT and DDE detection limits were high
tundra over much of these basins, and there is less rea-
and, therefore, it is not surprising that almost no resi-
son to expect the use of -HCH in these regions. It is
dues were found to be above the low µg/L range.
noted that the 1990 observations were during the period
Four of the five monitored rivers flowing to the Kara
when HCH usage for agriculture was still high. While
Sea (the Ob, Nadym, Pur, and Taz) were characterized
there are no significant agricultural activities in the re-
by much higher levels of reported OC pesticides than
gion, mining is extensive, and the extent of pesticide use
were rivers flowing to the White and Barents Seas. The
in support of such activities, as with forestry, is un-
fifth, the Yenisey River, is significant for loadings but less
known.
so for concentrations. The averages of the annual means
for -HCH, -HCH, p,p'-DDT, and p,p'-DDE in these
Other chlorinated pesticides in Russian Arctic rivers
four rivers were, respectively: 0.028; 0.050; 0.015; and,
-HCH was analyzed in water from northern Russian
0.0022 µg/L, although the contributing means had a
rivers but was not detected at any site. The lack of ob-
high level of variability, and the Ob had more samples
servations was expected given that the - and -HCH
contributing to its annual means than did the other
isomer levels are near their limits of detection. In Cana-
rivers. Babkina (1999) reported that agricultural usage
dian Arctic rivers, the levels of -HCH were also less
and soil concentrations of -HCH in the river basins
than detection limits (approximately 0.00002 µg/L) (Jef-
and sub-basins studied here were significant only in the
fries et al., 1996). In Norway, they were not reported
upper Ob-Irtysh Basin, and to a lesser extent, in the
(Holtan et al., 1994).
upper Yenisey Basin. The Ob River (and its tributary, the
The rivers flowing to the Kara Sea were the only ones
Irtysh River) drain agricultural areas in the south of Rus-
in which the insecticide degradation product DHH was
sia and in Kazakhstan, which have received high pesti-
investigated. This compound may have been used in
cide applications including -HCH. The observation
forests against biting insects, as well as in the agricul-
that the shorter, non-agricultural Nadym, Pur and Taz
tural industry. The overall mean of the reported years/
rivers exhibited -HCH levels as high as or higher than
rivers was 0.0042 µg/L and, at least for the Ob, the sam-
those of the Ob lends weight to the premise that forestry,
ple numbers were considerable. For all of f SU/Russia,
mining or other usage was significant in those basins.
580 and 520 t/yr of DHH were used in 1990 and 1991,
For the HCHs in the Ob, there appears to be a tran-
respectively (Alexeeva et al., 1997), and the Ob Basin
sition around 1993-1994 as concentrations before this
accounted for 12% of these amounts in both years. Data
period are much higher than those after. Alexeeva et al.
for later years are not available. This pesticide has not
(1997) reported total HCH usage in Russia at roughly
been investigated in Canadian or Norwegian rivers.
5000 t/yr for the period 1970 to the mid-1980s, and
falling to 600-700 t/yr by the late 1980s. HELCOM (2001)
Loadings of OC pesticides in the northern Russian seas
reports lindane use in Russia at 13.7 t in 1990 and 5.9 t
The loadings of HCHs and DDTs (1990-1996) are
in 1996. Unpublished data (Babkina, 1999) show that
illustrated in Figure 4 ·17. The Kara Sea received, by far,
there was a further sharp reduction in use of HCH in the
the largest fraction of OC pesticide discharges going to
upper Ob-Irtysh Basin around 1992 and that collec-
the northern seas; well over 90% of the totals for three
tively, the usage in this basin before this time was a sig-
of the four measured organics. - and -HCHs and
nificant fraction (approximately 1/3) of the amounts re-
p,p'-DDT flowed to the Arctic largely via the Ob River
ported for all of the former Soviet Union (f SU) in the
( -HCH 50%, -HCH 53%, p,p'-DDT 72%); DDE
late 1980s. The reductions in HCH usage in these upper
largely (76%) entered the Laptev Sea via the Lena River
reaches of the river are roughly reflected in the water
in 1990. Since DDT has been banned for more than 25
concentrations at the river mouth, indicating a fairly
years, this material may be partly from soil and de-
rapid system response time.
posited material applied earlier (Harner et al., 1998),
Average flux, tonnes/yr
20
Kolyma
15
Kola
Lena
10
Olenek
Onega
Yenisey
Anabar
Severnaya Dvina Mezen
5
Pechora
Ob
Taz
0
Nadym
HCHs
DDTs
Figure 4·17. Average annual fluxes of DDTs and
HCHs to the Arctic Ocean from Russian rivers,
1990-1996 (Alexeeva et al., 2001).
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
63
although a higher proportion of DDE would be ex-
OC concentration
pected than was observed. The loadings of HCHs were
in lake/river water, ng/L
greater than those of DDT and DDE, except for DDE
1.0
in the Lena in 1990, for which there is no known expla-
nation.
The Ob carried the major loadings of - and -HCHs
0.5
which, in the case of -HCH, was 50% of the total for
all of the rivers studied. The Yenisey was responsible for
a further 24% of the total. The Ob carried 53% of the
0
-HCH to the Kara Sea, while the Yenisey carried 18%
CHLs
CBz
of this isomer. A major fraction (1/3 based on data for
HCHs
DDTs
pre-1990 use) of Russia's agricultural use of HCH oc-
PCBs
curred in the upper reaches of these two rivers (and these
are the only reported uses in the northern river basins).
The observation that the Nadym, Pur, and Taz rivers
Kanchalan
also have significant loadings (and high concentrations)
of both of these isomers relative even to the Ob, indi-
cates other anthropogenic sources in these non-agricul-
tural watersheds. Forestry and mining are prominent in-
dustries in the area, and both use significant quantities
of pesticides to provide better working conditions in the
Khatanga
region.
Yenisey
These rivers represent the major loadings from the
(at Dudinka)
northern flows, but data are incomplete. Using the
AMAP data for total flows to the various seas (Gregor et
Pechora (at Nelmin Nos)
al., 1998), the basin loadings from the monitored rivers
in each northern sea were scaled up to account for the
Lovozero (lake)
rivers not monitored (those measured represented 58-80
% of the combined basin flows). The total annual load-
ings of the OCs were estimated to be 25 t for -HCH,
44 t for -HCH, 13 t for p,p'-DDT, and 6 t for p,p'-
DDE. The HCH values can be compared with the vari-
ous flux estimates previously reported for the Arctic
Figure 4·18. Concentrations of OCs in lake (Lovozero) and river
(Macdonald et al., 2000). Ocean current delivery via the
water in northern Russia (RAIPON/AMAP/GEF Project, 2001). Bars
Bering Strait was 52 and 12 t/yr for -HCH and -HCH,
are means (with ± 1
4.3.1.1.2
SE indicated when more than two pooled sam-
respectively and, via the atmosphere, 53 and 10 t/yr.
ples are available). All samples are pools of numerous samples col-
lected in 2000 -2001. Samples from Lovozero included surface and
depth samples. OC concentrations varied little with depth in Lake
4.3.1.2. Recent studies of OCs
Lovozero.
in Russian lake and river waters
assessed from the information available. OC concentra-
Samples of freshwater (15- 45 L) were collected from
tions are in the same range as levels reported previously
lakes and rivers in four regions of the Russian Arctic:
for Russian rivers.
Kola Peninsula (Lake Lovozero); Pechora River mouth
at Nelmin Nos; Taymir Peninsula (Yenisey River at
4.3.1.3. OCs in Canadian Arctic lake waters
Dudinka and Khatanga River at Khatanga), and at Kan-
chalan on the Kanchalan River in Chukotka, in 2000-
A very limited number of new measurements of POPs in
2001 for analysis of POPs (RAIPON/AMAP/GEF Pro-
freshwater have been carried out in the Canadian Arctic
ject, 2001). Samples from Lake Lovozero were collected
since the previous AMAP POPs assessment. Law et al.
at various depths (0 -30 m). There did not appear to be
(2001) summarized results for - and -HCH in lakes
trends in OC concentrations with depth, and therefore,
from Cornwallis Island (central Canadian Arctic Archi-
these data have been combined. Samples from all others
pelago) and the Yukon, and compared the results for
sites were collected from rivers near the surface. PCBs
Arctic lakes with the Great Lakes and small lakes in
were the predominant OC followed by DDTs and chlo-
south-central Ontario. Concentrations of -HCH ranged
robenzenes (Figure 4 ·18 and Annex Table 6). Toxa-
from 0.64 to 1.7 ng/L and -HCH ranged from 0.13 to
phene (sum of Parlars 26, 52, and 60; detection limits
1.3 ng/L. Sampling dates for the lake waters ranged
approximately 0.1 ng/L) and PBDEs (detection limits ap-
from 1993 (Yukon) to 1998 (Cornwallis Island). Declin-
proximately 0.5 ng/L) were not detected in any water
ing airborne levels of -HCH over this time period (Li et
sample but the detection limits of this study are above
al., 1998a) may have influenced the observed levels in
the levels that would normally be anticipated for these
surface waters. Highest concentrations of -HCH were
compounds in the water column.
found in large, cold and oligotrophic lakes, such as those
Except for HCHs, no geographical trends were obvi-
in the Arctic, subarctic, and the upper Great Lakes, and
ous for any OC group, although levels were slightly
this was attributed to greater inputs from atmospheric
higher in Lake Lovozero (Figure 4 ·18). Whether this is
deposition and slower loss rates relative to warmer, tem-
due to these being lake, versus river, samples cannot be
perate lakes.
64
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Helm et al. (2000) analyzed water from Amituk,
4.3.2.1. Russian river and lake sediments
Char, and Meretta Lakes for enantiomers and concen-
trations of -HCH to estimate the extent of biodegrada-
Sediment samples were collected from the same sites as
tion in watersheds in the Canadian High Arctic. -HCH
surface waters in four regions of the Russian Arctic
concentrations ranged from 0.839-1.021 ng/L in Char
(Kola Peninsula (Lake Lovozero); Pechora River mouth;
Lake and 1.205-1.264 ng/L in Merreta Lake. By com-
on the Taymir Peninsula, the Yenisey River at Dudinka
parison, -HCH was present at concentrations of 0.520-
and Khatanga River at Khatanga; and, at Kanchalan on
0.688 ng/L in the water column of Amituk Lake (Falco-
the Kanchalan River in Chukotka) in 2000/2001 and
ner et al., 1995) and at 0.119-0.529 ng/L in inflowing
were analyzed for POPs (RAIPON/AMAP/GEF Pro-
streams. The -HCH ERs declined with increasing stream
ject, 2001). A single pooled sample was analyzed from
temperatures indicating greater rates of biodegradation
each region based on samples collected at either 0-2 cm
of -HCH. As stream flows declined during the summer
(Lovozero) or 0-5 cm depth (all others). PCBs were the
so too did stream volume-to-surface ratios, resulting in
dominant OCs in the freshwater sediments followed by
greater contact time between water and bed surfaces.
DDT (Annex Table 6). Toxaphene (sum of Parlars 26,
The results suggest that enantioselective degradation
52, and 60; detection limits approximately 0.1 ng/L) and
was enhanced by the greater contact time between the
PBDEs (detection limits approximately 0.5 ng/L) were
chemical in the water and stream or slope substrates, the
not detected in any freshwater sediment sample.
presumed site of microbial communities. Approximately
OC concentrations were similar in all regions of Rus-
7% of -HCH in the Amituk Lake Basin was enantiose-
sia with the exception of DDT concentrations in Pe-
lectively degraded prior to entering the lake. ERs within
chora sediment (Annex Table 6). Concentrations of
Amituk Lake were controlled by meltwater inputs rather
DDT in this region were 70 times higher than the other
than within-lake degradation, and clearly illustrate the
regions. This sample was a pool of ten subsamples from
riverine-like nature of High Arctic lakes.
the Nelmin Nos area of the river. The ratio of DDT iso-
Differences in the lake -HCH inventory from the
mers to DDT in the Nelmin Nos sediment is 0.67 com-
end of summer 1993 to spring 1994 indicate that from
pared to 0.2- 0.24 in the other sediments analyzed in the
33 to 61% of -HCH within the lake may have been
RAIPON/AMAP/GEF Project. DDT isomers predomi-
lost via non-enantioselective microbial degradation at a
nate in newly synthesized DDT, but are converted to
rate ranging from 0.48 to 1.13/yr. In comparison to the
DDE and DDD isomers in the environment.The high
average ER of 0.75 in Amituk Lake, the average ERs in
concentrations of DDTs and the high ratio of DDT to
the oligotrophic Char Lake and the more productive
DDTs in the Pechora sediment suggest recent use of
Meretta Lake were 0.65 (range 0.62- 0.69) and 0.88
DDT in this region.
(range 0.84 - 0.90), respectively. These differences are
Skotvold and Savinov (2003) reported PCB10 (sum
likely attributable to within-lake degradation that is a
of ten major congeners) in surface (0-2 cm) sediment
function of lake water residence times, which are 9-14
samples from 11 coastal tundra ponds collected along
yr for Char Lake, 3 yr for Amituk Lake, and < 3 yr for
the Russian Arctic coast from the southeastern Barents
Meretta Lake, rather than degradation within streams or
Sea to the East Siberian Sea in 1994-95. Most of these
lake productivity. Law et al. (2001), in a survey of 24
data were previously reported in the AMAP POPs as-
lakes, including the lakes studied by Helm et al. (2000),
sessment (de March et al. 1998) but not discussed in de-
also noted an inverse relationship between enantioselec-
tail. Mean PCB concentrations ranged from 0.38±0.22
tive degradation and lake trophic status inferred by
ng/g dw for three ponds on the Laptev Sea coast to
phosphorus and nitrogen concentrations.
7.9 ± 9.9 ng/g dw for three ponds on the Kara Sea coast.
Only one sample collected in a pond located on Bay-
daratskaya Bay coast had a relatively high PCB
4.3.2. Levels and fluxes of OCs
10 con-
in lake and river sediments
centration (19.3 ng/g).
Overall the PCB concentrations in Russian freshwa-
A significant number of studies on OCs in sediment
ter lake/river sediments analyzed by the recent RAIPON/
were carried out prior to, and summarized in, the origi-
AMAP/GEF Project are at similar low ng/g (dw) levels
nal AMAP POPs assessment, allowing for examination
when compared to results from the major north-flowing
of circumpolar trends (de March et al., 1998). A limited
rivers in Russia reported in the first AMAP POPs assess-
number of studies of POPs in freshwater sediments have
ment (de March et al., 1998). Concentrations in Lake Lo-
been conducted since the previous AMAP POPs assess-
vozero sediments were similar to those reported by Skot-
ment. In this section, we examine studies of concentra-
vold and Savinov (2003) for lakes in northern Finnmark
tions and fluxes in surface sediments and their spatial
and on the southeastern Barents Sea coast. However, the
variation. Historical profiles are examined in Section
DDT concentrations in the pooled sediment sample
5.3.1. Most of the studies in this assessment involved
from the Pechora mouth exceeded concentrations previ-
lakes and rivers that are remote and where POPs inputs
ously reported in the first AMAP POPs assessment for
are likely due to long-range transport and deposition.
the major north-flowing rivers in Russia (de March et al.,
Urban/industrial sources of contamination, however, may
1998). In the present dataset (Annex Table 6) one site,
be important in rivers in Russia as well as in the North-
Watson Lake, in the Yukon in the Western Canadian Arc-
west Territories and Yukon in Canada and are also
tic had higher DDTs than the sample from the Pechora.
considered. The first AMAP assessment concluded that
The Watson Lake area was known to have received
there were no global latitudinal or longitudinal trends of
DDT applications for biting-fly control in the 1950's
OCs in Arctic lake sediment, although fluxes of OCs de-
(Rawn et al., 2001) and use of DDT for this purpose
clined with latitude if temperate lakes were included.
may be the source of the DDT in the Pechora as well.
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
65
than in those from southern Sweden or northern/central
4.3.2.2. Lake sediments in northern Norway
Norway. This complicates the geographical comparison
and Sweden
since only recent deposition may be measured in high
Skotvold and Savinov (2003) determined PCB10 in sur-
sedimentation sites versus longer-term deposition at low
face bottom sediments (0 -2 cm depth) collected from 26
sedimentation sites.
remote lakes in northern Norway in 1994 and 1995 and
previously reported, but not discussed in detail, in the
4.3.2.3. Sediments from lakes on Bjørnøya
AMAP POPs assessment (de March et al., 1998).
PCB10 levels in sediments from one lake on Svalbard
Sediment cores were taken from two small lakes (El-
(Barentsvann) and four in Nordland (northern/central
lasjøen and Øyangen) on Bjørnøya in 1996 for OC
Norway) were significantly higher compared to other
analysis as part of a larger study (Section 4.3.5). Con-
areas to the east. Significantly lower PCB10 levels were
centrations of all OCs were much higher in Ellasjøen
found in southwestern and northern Finnmark and the
compared to Øyangen. The concentration of PCBs in
coast of the East Siberian and southeastern Barents Seas
surface sediment from Ellasjøen (PCB7 = 60 ng/g dw)
compared to the lakes in Nordland, Svalbard, and
was an order of magnitude higher than in Øyangen
Bjørnøya. The highest PCB concentrations were found
(PCB7 = 4.4 ng/g dw). As previously noted, the concen-
in the lake Ellasjøen on Bjørnøya as discussed in Section
trations found in the sediments of Ellasjøen are the high-
4.3.2.3.
est found for a remote lake in the Arctic. In Ellasjøen,
Rose et al. (2003) found PCB10 concentrations for
guano from seabirds was identified as a potential source
surface sediments from five lakes along the west coast of
of contaminants (Evenset et al., 2002). Levels reported
Svalbard sampled in 1997 that ranged between 2.5 and
for Øyangen are in the range generally reported for lakes
13.5 ng/g (Annex Table 6). This study involved the ana-
in northern Norway and Sweden (Skotvold and Savinov,
lysis of surface (0-1 cm) and pre-industrial sediments
2003).
from dated cores. Highest concentrations and fluxes
DDT isomers make up a small percentage of the total
were recorded in the surface slice of a core from the lake
DDTs in lake sediments from Bjørnøya indicating that
Tenndammen located near the coal mining towns of Bar-
atmopheric input (and/or guano inputs in the case of El-
entsburg and Longyearbyen. This lake also showed ele-
lasjøen) was the primary source.
vated spherical carbonaceous particles and PAHs in sur-
The only chlordanes with concentrations above the
face slices compared to the other lakes on Svalbard, al-
detection limit in the surface sediment from Øyangen
though levels of contamination were low compared to
were cis-chlordane and trans- and cis-nonachlor at 0.08,
European sites (Rose et al., 2003).
0.06, and 0.03 ng/g dw, respectively. These same com-
A latitudinal study of organochlorine contamination
pounds were present at concentrations two to four times
in bottom sediments of 100 Swedish lakes, many of
higher (0.17, 0.22, and 0.10 ng/g dw, respectively) in
which were part of the National Swedish Environmental
surface sediments from Ellasjøen. Oxychlordane, trans-
Monitoring program (Swedish Monitoring Program,
chlordane, and cis-chlordane were also detected in El-
2002), included two lakes from the Swedish Arctic
lasjøen (0.11, 0.05 and 0.04 ng/g dw, respectively). Hep-
mountains and other other high latitude lakes (Söder-
tachlor and its oxidation product, heptachlor epoxide,
ström et al., 2002). This study compared concentrations
were below the detection limit in all sediment samples.
of PCBs (seven congeners), three DDT-related com-
Concentrations of -HCH and -HCH in the surface
pounds, HCB, and three HCH-isomers in surface (0 -2
sediments from Ellasjøen and Øyangen were relatively
cm) samples of each lake. The six Swedish Arctic lakes
low (< 0.2 and < 0.4 ng/g dw, respectively), as were the
had significantly lower mean concentrations of PCB
concentrations of HCB (< 0.8 ng/g dw). Dieldrin was
(0.9 ± 0.5 ng/g dw), DDTs (1.0±1.0 ng/g dw), and HCH
present at 0.51 ng/g dw in the surface sediment in El-
(0.1 ± 0.05 ng/g dw) than southern lakes (9.2 ± 6.3 ng/g
lasjøen. None of these pesticides could be detected in the
dw, 14.6 ±12.1 ng/g dw, and 1.3 ±1.5 ng/g dw, respec-
sediment from Øyangen.
tively). For HCB the six northern lakes had about three-
fold lower concentrations than the 60 southern lakes in
4.3.2.4. North American Arctic lake sediments
the study, reflecting the longer atmospheric half-life of
HCB than the other compounds and lack of major past
Concentrations and fluxes of POPs in lake sediments
local uses in the south.
have been recently reported for about 14 lakes in the
These studies in Sweden and the Norwegian and
North American Arctic (Cleverly et al., 1996; Lockhart,
Russian Arctic illustrate how a large array of lakes can
1996; 1997; Macdonald et al., 2000; Muir et al., 2002b;
be used to assess broad geographical trends in deposi-
Rawn et al., 2001; Stern and Evans, 2003). When com-
tion of POPs. Similar approaches have been used in
bined with previous studies in Alaska and northern
North America (e.g., Muir et al., 1995a; 1996a), but
Canada that were reviewed in the AMAP POPs assess-
with far fewer and less well characterized lakes than
ment (de March et al., 1998) results are available for
in Sweden or Norway. A limitation of this approach is
about 30 lakes. Similar to the approach used in studies
that, generally, the sediment cores were not dated, thus
in Norway and Sweden, sediment cores from the deepest
sedimentation rates and the degree of particle focusing
point in each lake have been used in almost all studies in
are not known. Given generally lower sedimentation
the North American Arctic. However, most of the sedi-
rates, especially in the Arctic mountain lakes and in
ment cores have also been dated using the 210Pb or 137Cs
other lakes above the tree line, it is reasonable to as-
techniques (Oldfield and Appleby, 1984) which yields an
sume that a much longer period of deposition was rep-
estimate of sedimentation rates and particle focusing
resented by the 2-cm layer in the high latitude lakes
factors. Thus fluxes (concentration
sedimentation
66
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Flux, ng/m2/yr
650
DDTs
300
200
Lindeman
Laberge Fox
100
Hanson
Chandler
Yaya
Great Bear
0
Great Slave
Fox
Yaya CharDV09
AX-AJ
Laberge
Hanson
Lindeman
Romulus
Great Slave Great Bear
Char
AX-AJ
4000
DV90
Romulus
PCBs
3000
Ossian
Ytertjørna
2000
Daltjørna
1000
0
Fox
Yaya CharDV09 ørna ørna
AX-AJ
Laberge
Hanson
Ossian
Lindeman
Chandler
Daltj
Romulus
Ytertj
Great Slave Great Bear
Figure 4·19. Fluxes of DDTs and PCBs in lake sediment cores (averages for slices dated to the 1990s) from the Canadian Arctic and Sval-
bard. Lakes are arranged by increasing latitude from left to right. A significant decline with increasing north latitude was observed for both
DDT and PCB. Lakes with significant influence of local inputs are omitted.
rate) of POPs to lake sediments can be calculated over a
Laberge (Rawn et al., 2001). PCB concentrations in
wide geographic area in the North American Arctic.
Lindeman and Kusawa Lake surface sediments, both
Fluxes (post-1990) of DDTs and PCBs reported re-
very remote from urban areas in the Yukon, were low
cently in 14 lakes in the North American Arctic and, for
relative to the other Yukon lakes that were studied (An-
PCBs, in three lakes on Svalbard (Rose et al., 2003) are
nex Table 6).
shown in Figure 4·19.
Concentrations of HCHs and CHLs in surface
sediments of the seven lakes studied by Rawn et al.
Alaska
(2001) were generally in the low ng/g range, consistent
Cleverly et al. (1996) measured fluxes of PCBs, includ-
with a predominantly atmospheric input source (Annex
ing coplanar PCBs, as well as PCDD/Fs in a dated sedi-
Table 6). Subsurface maximum HCH concentrations
ment core from Chandler Lake in northern Alaska. These
were observed in all but Lindeman Lake. - and -HCH
data were not included in the previous AMAP POPs as-
were the dominant isomers contributing on average, 39
sessment. Very low concentrations of PCBs were de-
and 52%, respectively, to HCHs. Elevated levels of
tected (Annex Table 6) and fluxes were among the low-
CHLs were observed in slices dated to the 1970s and
est observed in Arctic lake sediments (Figure 4·19).
early 1980s in Fox, Kusawa, Hanson, and Lindeman
Gubala et al. (1995) found similar low fluxes of PCBs
Lakes. Peak concentrations were measured in the surface
and OC pesticides in a sediment core from Wonder Lake
sediment from Atlin Lake (3.87 ng/g dw).
and lower fluxes in Schrader Lake in northern Alaska.
Evans et al. (1996) examined concentrations and
Overall, knowledge of fluxes of PCBs and OC pesticides
fluxes of PCBs, OC pesticides, and PCDD/Fs in Great
to lakes in Alaska is very limited.
Slave Lake. This study was not reported in the previous
AMAP POPs assessment. Great Slave Lake, which is the
Canadian Arctic lakes
fourth largest lake in Canada in terms of both surface
Rawn et al. (2001) reported fluxes and historical pro-
area (27 000 km2) and volume (2088 km3), is a rela-
files of PCBs and OC pesticides in sediment cores from
tively pristine ecosystem with low concentrations of or-
six lakes and from one alpine lake in northern British
ganic contaminants in all but the most industrialized
Columbia within the Yukon River watershed. Surface
areas (Mudroch et al., 1992). Greater than 50% of the
concentrations and maximum concentrations in the core
population in the Northwest Territories resides along
are presented in Annex Table 6. Several lakes showed
the shores of Great Slave Lake. The Slave River, which
evidence of local contamination. The highest PCB and
receives the majority of its water from the Peace and
DDT levels were measured in deep sediments from
Athabasca rivers, is the major river entering Great Slave
Watson Lake, although levels were much lower in sur-
Lake and contributes some 87% of the total annual in-
face sediments. Both chemicals showed increases in the
flow of 135 km3 (Evans et al., 1996).
mid-1940s consistent with the use of pesticides for bit-
Sedimentation rates were highest near the mouth of
ing-fly control during the building of the Alaska High-
the Slave River and decreased with increasing distance
way. Hanson Lake was treated with toxaphene, and
from the river mouth (Figure 4·20 a). Sedimentation
Lockhart et al. (1997) and Vetter et al. (1999) have re-
rates were very low at the westernmost sampled station
ported the profile of toxaphene congeners in sediments
and roughly comparable to that in the East Arm of
from this lake. Sediment cores also revealed evidence for
Great Slave Lake. Most sediments (and associated con-
past use of DDT in the region, especially in Lake
taminants), therefore, are likely to be deposited in the
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
67
Lockhart R.
Rae
Reliance
Yellowknife
a
Snowdrift R.
b
Sedimentation rate,
PCB concentration
g/m2/yr
in surface sediments,
1000
ng/g dw
5
Providence
Fort Resolution
T
500
S
alt
S
Hay River
l
s
a
o
l
n
a
0
v
R
v
e
.
e
.
R
R
R
.
.
.
ay
R
H
0
uffalo
B
c
d
PCDF concentration
PCDD concentration
in surface sediments,
in surface sediments,
pg/g dw
pg/g dw
20
50
40
30
10
S
S
l
20
a
l
v
a
e
ve
10
R.
R.
0
0
Figure 4·20. a) Sedimentation rates, b) PCB concentrations, c) PCDF concentrations, and d) PCDD concentrations in surface sediments of
Great Slave Lake (Northwest Territories, Canada).
deeper regions immediately offshore of the mouth of the
Surface and maximum concentrations of major OC
Slave River.
pesticides and PCBs in sediment cores from five isolated
PCB (70 congeners) and PCDDFs (major 2,3,7,8-
lakes in the Canadian Arctic Archipelago (Stern and
substituted tetra- to octachlorinated congeners) were high-
Evans, 2003; Muir et al., 2002b) are presented in Annex
est in sediments offshore of the river mouth and decreased
Table 6. Surface PCB concentrations (0.5 cm depth)
with increasing distance from the river mouth (Figure
were relatively similar in all lakes ranging from 0.96 to
4·20 b,c,d). This, combined with the higher sedimenta-
3.7 ng/g dw. HCHs had the widest range of concentra-
tion rates in this region, indicates that contaminant fluxes
tion in surface sediments (0.01- 0.69 ng/g dw). Historical
of these compounds to the sediments were substantially
profiles of POPs in several of these lakes are discussed in
greater offshore of the river than with increasing dis-
Section 5.3.
tance away from the river mouth. The converse pattern
was observed for PCDFs, which tended to occur in high
Geographic trends in deposition of PCBs and DDT
concentrations in the East Arm of Great Slave Lake.
in lake sediments
Lockhart (1997) analyzed a sediment core from Yaya
Recent (1990s) fluxes (ng/m2/yr) of PCBs and DDTs
Lake, an isolated lake in the Mackenzie Delta (Annex
in sediment, corrected for particle focusing, for selected
Table 6). Surface concentrations of major OC pesticides
lakes in the Canadian Arctic, Alaska, and Svalbard are
and PCBs in this core were very low, consistent with its
shown in Figure 4·19. Lakes for which past local inputs
isolated location relative to Great Slave Lake (Figure
were thought to be significant, such as Watson and Little
4·19). Graf Pannatier (1997) examined concentrations
Atlin Lakes in the Yukon (Rawn et al., 2001), and the
and fluxes of PCBs and OC pesticides in a series of `clo-
lake Tenndammen near mining towns in Svalbard, were
sure' lakes (connected to the Mackenzie River and
omitted, as were Lakes 6 and 7 due to direct inputs of
flooded annually in the spring freshet) in the Mackenzie
sediments from Mackenzie River flooding (Graf Pan-
Delta. These lakes were characterized by very high sedi-
natier, 1997). DDT fluxes in all of the high latitude
mentation rates of 2300 -12 200 g/m2/yr due to annual
lakes, were two-fold or more lower than reported for
sediment deposition from flooding. This was much
Yukon or NWT lakes, but similar to fluxes found in
higher than nearby Yaya Lake (480 g/m2/yr) which is
northern Alaska (Gubala et al., 1995), and to previous
not flooded as frequently (Lockhart, 1997). Concentra-
reports for cores from four High Arctic lakes collected in
tions of PCBs and major OC pesticides in sediment
the late 1980s and early 1990s (Muir et al., 1995a;
cores from Lakes 6 and 7, two middle delta lakes, were
1996a). DDT fluxes ranged widely; Fox, Lindeman, and
low and similar to those in Yaya Lake (Annex Table 6).
Hanson Lakes in the Yukon had similar fluxes to Great
68
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Slave and Yaya Lakes, while Lake Laberge had a much
SCCPs (17.6 ng/g dw) in the surface slice of a core from
higher flux reflecting some continued input from old
Lake DV09 on Devon Island. The possibility of contam-
sources within the watershed. PCB fluxes in all of the
ination from SCCPs, which are widely used as flame re-
high latitude lakes in Canada and in Svalbard (Rose et
tardant plasticizers and in cutting oils for metal machin-
al., 2003) were also lower than lakes in the Yukon and
ing cannot be ruled out, especially where there is a sig-
Northwest Territories, but higher than in most Alaskan
nificant amount of small-boat traffic such as in Fox
lakes (Cleverly et al., 1996; Gubala et al., 1995). A sta-
Lake. However, the results also indicate that long-range
tistically significant decline in fluxes of PCBs and
atmospheric transport and deposition were probably the
DDTs with latitude was observed, reflecting the higher
major pathways for SCCPs to the very remote lakes
fluxes in the western Canadian Arctic lakes (Figure
(Yaya, DV09, and Hazen).
4·19). This decline with increased northern latitude was
No reports were found on SCCPs or other `new'
also observed for higher chlorinated PCBs by Muir et al.
POPs in lake sediments from the European Arctic.
(1996a) and for DDTs by Muir et al. (1995a) when re-
mote lakes from northwestern Ontario were included in
4.3.2.7. PAHs in Arctic lake sediments
the regression.
PAHs in freshwater sediments were not assessed in the
previous AMAP assessment. Here we confine the discus-
4.3.2.5. PCDD/F fluxes to lake sediments
sion primarily to pyrogenic PAHs in dated lake sediment
cores. Fernández et al. (1999; 2000) calculated fluxes of
Cleverly et al. (1996) reported planar PCBs and PCDD/Fs
23 PAHs for the lake Arresjøen on northwestern Sval-
in a sediment core from Chandler Lake in northern
bard (79°40'N) and Øvre Neådalsvatn (62°46'N) in the
Alaska. The flux of total TCDD TEQs, based on PCBs
Caledonian mountain range of central Norway. Major
and PCDD/Fs were 8.7 pg TEQ/m2/yr in the surface slice
PAHs in Arresjøen were primarily pyrolytic in origin
from this core. The TEQs were mainly due to CB126,
(i.e. resulting from combustion of coal and hydrocarbon
2,3,7,8-TCDD, and 1,2,3,7,8-pentachlorodibenzo-p-di-
fuel burning) such as phenanthrene, fluoranthene, py-
oxin. PCDD/Fs have also been determined in sediments
rene, chrysene/triphenylene, indeno[1,2,3-c,d]pyrene and
from a laminated core from Lake DV09 on Devon Is-
benzo[g,h,i]perylene. Fernández et al. (1999) concluded
land (Stern and Evans, 2003). The surface and maxi-
that the PAH deposition pattern in high altitude moun-
mum deposition flux values for PCDDs to Lake DV09
tain lakes, including Arresjøen, paralleled sulfate depo-
were calculated to be 0.01 and 0.36 pg TEQ/m2/ yr, re-
sition, pointing to combustion particles as the main in-
spectively. The historical trends in PCDD/F deposition in
put pathway. Rose et al. (2003) determined 15 PAHs in
this core, which had much higher temporal resolution
surface and prehistorical slices of sediment cores from
than the one from Chandler Lake, are discussed in Sec-
four lakes in Svalbard. Highest fluxes were found in the
tion 5.3.
lake Tenndammen (360 µg/m2/yr) a lake within 20 km
Using the PCDD/F emission inventory for Canada
of the coal mining towns of Barentsburg and Longyear-
and the U.S., Commoner et al. (2000) predicted `dioxin'
byen. PAH fluxes in the four Svalbard lakes appeared to
toxic equivalents (TEQ) deposition of about 4 -53 pg
decline with distance from the Barentsburg/Longyear-
TEQ/m2/yr to terrestrial surfaces near eight communities
byen area.
in the eastern Canadian Arctic which is in reasonable
Fluxes of PAH (the same 23 PAHs as analyzed by
agreement with observations of Cleverly et al. (1996)
Fernández et al. (1999) minus perylene and retene) have
but an order of magnitude higher than reported for the
also been reported in a series of studies of dated sedi-
Devon Island core.
ment cores from the Canadian Arctic (Lockhart, 1994;
Evans et al. (1996) determined PCDDs and PCDFs in
1996; 1997; Muir and Lockhart, 1994; Lockhart et al.,
surface sediments and sediment cores from Great Slave
1995; 1997). Total PAH fluxes in Yukon lakes ranged
Lake (Figure 4·20). PCDD concentrations were highest
from 9.1 µg/m2/yr in remote Kusawa Lake to 174 µg/
in sediments offshore of the Slave River mouth and de-
m2/yr in Little Atlin Lake (Lockhart et al., 1997). Two
creased with increasing distance. This, combined with
remote lakes in the Mackenzie River Basin, Lac Sainte
the higher sedimentation rates in this region, indicates
Therese and Yaya Lake, had high PAH fluxes (68 and
that contaminant fluxes of these compounds to the sedi-
140 µg/m2/yr, respectively) (Lockhart, 1997).
ments were substantially greater offshore of the river
Graf Pannatier (1997) determined PAHs (unsubsti-
than with increasing distance away. The converse pat-
tuted as well as methyl naphthalenes and phenanthrenes)
tern was observed for PCDFs, which tended to occur in
in sediment cores from four `closure' lakes in the Mac-
high concentrations in the East Arm of the lake.
kenzie River Delta. Concentrations of PAHs in surface
No reports were found on PCDD/Fs or coplanar PCB
sediments (0 -1 cm) ranged from 650 to 900 ng/g dw.
deposition to sediments in the European Arctic.
Due to high sedimentation rates in these lakes resulting
from annual deposition in the spring freshet, fluxes of
4.3.2.6. `New' chemicals in Arctic sediments
PAHs in these lakes were in the range of 4-11 mg/m2/
yr, well above fluxes for nearby Yaya Lake which is
Tomy et al. (1999) determined SCCPs in three Arctic
flooded less frequently. High PAH values have also
lake sediment cores previously analyzed by Muir et al.
been found in Mackenzie River suspended particulates
(1996a) and Lockhart (1997). Surface concentrations
and they are thought to be mainly of petrogenic origin
(0 -1 cm) ranged from 257 ng/g dw in Fox Lake (Yukon)
(Yunker and Macdonald, 1995).
to 1.6 ng/g dw in Yaya Lake (Mackenzie Delta). Lake
Concentrations and fluxes of PAHs were also deter-
Hazen had intermediate concentrations of SCCPs. Stern
mined in sediment samples from Great Slave Lake
and Evans (2003) reported maximum concentrations of
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
69
Rae
Reliance
Yellowknife
PAH concentration
in surface sediments,
ng/g dw
1500
Providence
1000
500
Fort Resolution
0
Hay River
Sla
Figure 4·21. Concentrations of PAHs in surface sediments
ve
of Great Slave Lake (NWT, Canada) (Evans et al., 1996).
(Evans et al., 1996). PAH concentrations, like those for
few important exceptions that can be attributed to in-
PCDD/Fs, were highest in sediments offshore of the
creased exposure or unique biological variations. For ex-
mouth of the Slave River and decreased with increasing
ample, elevated levels of OCs in the lake Ellasjøen on
distance (Figure 4 ·21).
Bjørnøya, north of Norway, have resulted in high OC
The recent (late 1980 -1990s) PAH fluxes for the Eu-
ropean and Canadian Arctic are compared in Figure
4 ·22. In general, excluding the lake Tenndammen, higher
fluxes of substituted PAHs have been found in the
Mackenzie valley and Yukon lakes compared with the
European Arctic lakes. The large range of PAH fluxes in
Little Atlin
Kusawa
Laberge
Canadian Arctic lake sediment cores demonstrates that
Yaya
sources of PAHs are complex and could be due to natu-
Ste. Therese
Belot
ral petrogenic sources within the basin while at the same
time showing some characteristics of pyrolytic inputs.
Amituk
Hawk
4.3.3. Freshwater fish and invertebrates
Freshwater fish are an important component in the diet
Arresjøen
Ossian
Tenndammen
of many northern communities, and a variety of tissues
Ytertjørna
Daltjørna
may be consumed. OC concentrations observed in fresh-
water invertebrates and fish appear to be predominantly
controlled by exposure (i.e. regional differences) and
Øvre Neådalsvatn
trophic level, with levels in various tissues determined by
lipid content. OCs have been shown to biomagnify in
Arctic freshwater food webs, which results in the great-
est concentrations in the highest trophic-level fish (Kidd
PAH flux, µg/m2/yr
et al., 1998). To accurately assess spatial and temporal
350
trends of OCs in fish, the length, age and growth rates
need to be considered because all can have an impact on
300
observed OC concentrations (Johnston et al., 2002). In
250
light of this, observed relationships in this section need
to be viewed with caution because these parameters
200
were not considered in most studies, making compar-
150
isons of different studies difficult.
100
A fairly large dataset on OCs in freshwater fish and
invertebrates was assessed for the first AMAP POPs as-
50
sessment (de March et al., 1998); since 1996, a smaller
0
amount of additional data has been produced. This is
ørna øen
ørna
likely due, in part, to the low concentrations of OCs
Yaya
Belot
Kusawa
Laberge
Amituk Hawk
Ossian
Daltj
generally found in Arctic freshwater systems when com-
Little Atlin
ådalsvatn
Ytertj Arresj
Ste. Therese
Tenndammen
pared to temperate freshwater and Arctic marine sys-
vre Ne
Ø
tems. In general, concentrations (lipid corrected) of OCs
Figure 4·22. Recent fluxes of total PAH (23 PAHs minus perylene
in freshwater fish of the same species are similar through-
and retene) in dated lake sediment cores from the Canadian and Nor-
out the Arctic (within an order of magnitude), with a
wegian Arctic. Lakes are organized longitudinally from west to east.
70
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
concentrations in landlocked Arctic char from this lake
(Section 4.3.5). PCBs and toxaphene continue to be the
predominant OCs in freshwater invertebrates and fish,
although data on toxaphene in the European Arctic are
limited, and some exceptions do exist.
Concentration
in burbot liver, ng/g lw
4.3.3.1. Invertebrates
3000
A fairly comprehensive dataset on OCs in zooplankton
from the Canadian Arctic was reviewed in the first
2000
AMAP assessment report. Observed spatial trends were
attributed to a combination of differences in water con-
Klukshu
1000
centrations and lake plankton biomass. Since this first
Kusawa
Fairbanks
Laberge
AMAP assessment, there have been few studies on OCs
0
in freshwater zooplankton (Annex Table 7). This is
Toxaphene
likely due to the low concern about OCs in freshwater
Fox
PCBs
zooplankton because of low concentrations and the fact
that they are not a human diet item.
Kanuti
Quiet
Data on OC concentrations in freshwater inverte-
Tetlin
Yukon Flats
brates were generated as part of a large study of OCs in
the lakes of Bjørnøya (see Section 4.3.5). Zooplankton
Nuiqsut
and benthic invertebrate samples were collected from
Fort Good Hope
three lakes (Skutilen, Ellasjøen, and Øyangen) on Bjørn-
Great Slave Lake
øya in 1996 and in 1999. Chironomid larvae and pupae
were also collected from fish stomachs in 1996 and in
Khatanga
1999. The levels of PCBs, HCB and DDTs in pooled
Yenisey (Dudinka)
samples of zooplankton and benthic organisms (Chi-
ronomidae sp. and Lepidurus arcticus) were greatest in
Ellasjøen, consistent with results in sediment and fish
(Figures 4 ·27 and 4 ·28, page 76). Sampled zooplankton
Lovozero
from Ellasjøen had higher concentrations of all the
measured contaminants than zooplankton from Sku-
tilen, followed by Øyangen with the lowest concentra-
tions. Chironomids from Ellasjøen had higher contami-
nant levels than the Lepidurus samples from the two
other lakes. L. arcticus from Øyangen had higher levels
of contaminants than L. arcticus from Skutilen. The
Figure 4·23. Spatial trends of PCBs and toxaphene in burbot col-
lipid content was very low in Lepidurus from Skutilen.
lected in Arctic Canada, Alaska, and Russia. Data for Lake Lovo-
Calculated on a lipid weight basis, the contamination
zero, Dudinka and Khatanga (Russian samples) were the sum of ten
levels were higher in Lepidurus from Skutilen than from
PCB congeners (no lipid content data was available for these sam-
Øyangen.
ples, and this was therefore assumed to be 30%); for Fairbanks,
4 3 3 2 1
Kanuti, Tetlin, and Yukon Flats, data were generated by the Aroclor
method; all other data by the summation of >50 PCB congeners.
4.3.3.2. Freshwater fish
Russian data from RAIPON/AMAP/GEF Project (2001); Fairbanks,
Kanuti, Tetlin, and Yukon Flats data are from Mueller and Matz
Russian Arctic fish
(2000); Nuiqsut data from Hoekstra (2002a), Great Slave Lake
POP analyses including PCDD/Fs were conducted on
data from Evans and Muir (2001), and Fort Good Hope and Fox
Lake data from Stern et al. (2001a); all other data are from Roach
samples of various tissues (liver and muscle) from a
(2002).
number of fish species collected in 2000-2001 from four
regions of the Russian Arctic: Kola Peninsula; Pechora
centrations were observed in burbot (Lota lota) livers.
Basin; Taymir Peninsula (Dudinka and Khatanga); and,
This was attributable to their predatory nature as well as
Chukotka (Kanchalan and Lavrentiya) (RAIPON/
the high lipid content of their liver. The lowest concen-
AMAP/GEF Project, 2001) (Annex Table 16). Species
trations were found in the whitefish species (Coregonus
analyzed for each location are found in Annex Tables 7
clupeaformis), a non-predatory fish. The relative differ-
and 16. This project addresses a major data gap for OCs
ences in concentrations between species in Russia are
in Russian freshwater biota identified in the first AMAP
similar to those observed in the Canadian Arctic.
assessment report (de March et al., 1998). However, the
Regional comparison of POP levels in Russian Arctic
somewhat limited sample numbers, current lack of bio-
fish is difficult because no one species was collected in
logical data (e.g., body size), and lack of lipid data con-
all regions. In burbot, the highest concentrations of
founds efforts to statistically compare the sites within
PCBs and DDTs were observed in samples collected
Russia with other locations, and such comparisons
from Dudinka on the Taymir Peninsula, which were 5-
should be viewed with caution.
10 times higher than concentrations observed on the
PCBs and DDTs were the predominant OCs found
Kola Peninsula and Khatanga on the Taymir Peninsula
across all species in Russian freshwater fish, followed by
(Annex Table 7). In general, concentrations of PCBs in
chlordane and HCH (Annex Table 7). The highest con-
burbot from Dudinka are among the highest found in
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
71
Arctic burbot, but levels on the Kola Peninsula and at
cies (Evans and Muir, 2000; 2001). In addition to water,
Khatanga are among the lowest (Figure 4 ·23). Again,
the Peace and Athabasca rivers, which flow into the
without information on lipid levels, it is difficult to draw
Slave River, transport tremendous amounts of sediments
conclusions about spatial trends. Since these data were
from the south into the Great Slave Lake ecosystem.
only recently generated, in-depth evaluation will be a fu-
This raises the possibility that increased development
ture priority.
to the south may be resulting in increased contaminant
Comparison of PCDD/F levels between fish species
transport to the lake through the Slave River, in addition
in different regions of Russia is also difficult due to lim-
to input via the atmosphere.
ited sample size and a lack of biological data (e.g., lipid
OC concentrations were similar between four species
contents) (Annex Table 16). In general, PCDD/F concen-
of predatory fish (northern pike (Esox lucius), walleye
trations were similar between species with the exception
(Stizostedion vitreum), burbot, and inconnu (Stenodus
of Arctic char from Lavrentiya, where concentrations of
leucichthys)) collected in the same region of Great Slave
PCDD were ten times higher. These fish are likely sea-
Lake (Annex Table 7), which is likely due to the fact that
all of these species predate predominantly on fish. OC
concentrations (on both a wet and lipid weight basis)
tended, however, to be slightly higher in fish collected in
Concentration
in whitefish muscle,
the East Arm of Great Slave Lake compared with the
pg/g ww
West Basin in 1993 and 1999, although this varied some-
0.4
what with the contaminant and/or fish species. The vari-
0.3
ation in concentrations between basins could be due to
differences in the characteristics of the fish (e.g., length
0.2
and/or age) collected for the two regions and/or the
0.1
characteristics of the two basins. OC concentrations and
sedimentation rates tended to be higher in lake sedi-
0
ments from the West Basin than in the East Arm. Lake
PCDFs
PCDDs
water in the East Arm is clear with low particulate con-
centrations, and invertebrates such as mysids and am-
phipods are strongly benthic. In contrast, in the West
Basin, waters are turbid with high concentrations of sus-
Great Slave Lake
pended silts and clays, and invertebrates spend less time
Khatanga
in close contact with the sediments than in the East Arm.
Biota inhabiting the East Arm of Great Slave Lake may
Dudinka
be accumulating higher body burdens of persistent OCs
than in the West Basin because these contaminants are
more bioavailable to them.
Pechora
Lovozero
Lake trout
Concentrations of OCs were determined in lake trout
muscle from a number of lakes in the Yukon and North-
west Territories in the late 1990s (Stern et al., 2000;
Evans and Muir, 2001; Roach, 2002). Previous work on
the Yukon lakes in 1993 found that OC concentrations
were particularly high in Lake Laberge, which was at-
Figure 4·24 Spatial trends of PCDD/Fs in muscle of whitefish col-
tributed to local point sources and a long food web
lected from Russian lakes and rivers in 2000-2001 (RAIPON/
(Kidd et al., 1995). Since that time, concentrations in
AMAP/GEF Project, 2001), and Great Slave Lake, NWT, Canada in
Lake Laberge lake trout have decreased up to four-fold,
1994 (Evans and Muir, 2001).
over the five-year period from 1993 to 1998 (see Section
run, which may explain the higher level observed. In
5.3.3). When the lipid-adjusted OC levels in lake trout
whitefish, PCDD/F concentrations were slightly higher
from Lake Laberge are compared to the other Yukon
in samples from the Kola Peninsula and Pechora Basin
lakes (1998 and 1999 collections only), levels in the
compared to eastern sites in Russia (Figure 4 ·24). Levels
Lake Laberge trout do not stand out as they did in the
of PCDDs are higher and PCDFs are lower in the Rus-
early 1990s. However, caution is warranted in interpret-
sian Arctic whitefish compared to levels observed in
ing these results as no effort was made to account for
Great Slave Lake whitefish in 1995 (Figure 4 ·24). PCDDs
differences in biological characteristics (e.g., size or age)
in the Russian fish were dominated by octachlorodi-
between the lake trout sampled in each lake. In some
benzo-p-dioxin, and 2,3,7,8-tetrachlorinated dibenzo-
lakes, much smaller trout were sampled.
furan (TCDF) had the highest concentrations among
Concentrations of the more lipophilic contaminants,
PCDFs.
such as toxaphene and PCBs, were much higher in lake
trout from Kusawa Lake (1998-1999), while lake trout
Great Slave Lake study
from Atlin Lake had the highest concentrations of the
A variety of studies have been conducted investigating
less lipophilic OCs (HCH and CBz) (Figure 4·25).
contaminants in biota in Great Slave Lake, Canada.
The lakes Kusawa and Atlin receive water from glacial
Most of these studies were conducted in the mid-1990s,
melt, which may, in part, explain high OC levels in fish
but monitoring has continued for a number of fish spe-
from these lakes. Glacial melt has been implicated as a
72
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Concentration in lake trout muscle, ng/g lw
100
HCHs
80
60
40
20
0
2000
PCBs
1500
1000
500
0
Toxaphene
3000
2000
Figure 4·25. HCH, PCB,
and toxaphene concentrations
in lake trout from the Cana-
1000
dian Arctic. Great Slave Lake
data from Evans and Muir
(2001), all other data from
0
Roach (2002).
Fox
Mandanna
Laberge
Kusawa
Atlin
Quiet
Coal
Gt.Slave(E) Gt.Slave(W)
1998
2000
1998
1999
1998
1999
1999
1999
1999
source of higher levels in fish from some lakes in Alberta
Levels of POPs were assessed in burbot livers from
(Blais et al., 2001). The levels of the different OC groups
Alaska (Fairbanks and Yukon Flats, Tetlin, and Kanuti
are not consistent between Kusawa Lake and Atlin
National Wildlife Refuges on the Yukon, Koyukuk, and
Lake, however, and OC levels in burbot liver from
Tanana rivers) in 1998, in part, to assess the influence of
these two lakes are not higher than those observed in
long-range transport of POPs on the freshwaters of the
other Yukon and NWT lakes. These data need to be as-
Alaskan interior (Mueller and Matz, 2000) (Figure
sessed in light of variable biological characteristics of
4·23). This study highlighted the influence of biological
the fish collected from each lake. For example, lipid
variability on OC concentrations. Lipid concentrations
was found to be a significant co-variate of OC concen-
were significantly positively correlated with dieldrin and
trations in lake trout from the Yukon lakes (Stern et
heptachlor epoxide concentrations. Weight was signifi-
al., 2000). Concentrations (lipid corrected) of most
cantly positively correlated with -chlordane, dieldrin,
OCs were higher in the Yukon lakes compared to Great
HCB, heptachlor epoxide, mirex, toxaphene, and trans-
Slave Lake (Figure 4·25).
nonachlor concentrations. This study also showed that
Lake trout from several sites in northern Norway
OC concentrations could vary between fish populations
had PCB levels of 0.23-3.2 ng/g ww in muscle (Annex
that are fairly close geographically. General patterns of
Table 7) (Schlabach et al., 2001). PCDD/F and non-
greater OC contamination in burbot livers from Yukon
ortho PCB levels expressed as TEQs were 0.17-0.84 pg/g
Flats and Fairbanks compared to Tetlin and Kanuti were
ww (13-34 pg/g lw) (Annex Table 16).
consistent, with significant differences in concentrations
for some analytes. Analysis of the data was complicated
Burbot
by differing lipid concentrations in samples, differing
There is a fairly large dataset on OCs in burbot that was
fish weights among sites, and by a small sample size at
reported in the previous AMAP assessment (de March
Yukon Flats. The greater concentrations of DDT and its
et al., 1998). Levels of OCs in burbot have received at-
metabolites and PCBs found at Fairbanks compared
tention because indigenous people consume their high-
with other sites likely reflect historical use of these com-
lipid liver, and the species has a wide distribution. In ad-
pounds within the city of Fairbanks and at nearby mili-
dition to Russian studies discussed above, a small num-
tary bases. Toxaphene concentrations were generally low.
ber of studies have been carried out on POPs in burbot
There were variations in OC concentrations in the
in North America since the previous AMAP assessment,
liver of burbot collected in the Alaskan, Russian, and
and all were focused on Alaska and the western Canada
Canadian Arctic (Figure 4 ·23). The highest OC concen-
Arctic.
trations, including PCBs and DDTs, were found in
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
73
Lake Laberge burbot, but these OC levels are similar to
studies is provided in Section 4.3.5. The 15N values in
previous measurements in burbot from this lake (Kidd et
muscle tissue of Arctic char were generally higher in El-
al., 1995; 1998). Burbot from Fairbanks and Yukon Flats
lasjøen (mean 18.1) than in Øyangen (mean 8.8 ),
had somewhat lower mean PCB concentrations than at
suggesting a different food web structure between the
Lake Laberge. The PCB concentrations observed in
lakes or an input of N that was enriched in 15N. Consis-
burbot of Fairbanks and Yukon Flats are likely due to
tent with the higher 15N values, the mean concentra-
local sources. Mean PCB concentrations in Russian
tions of OCs were greater in the Ellasjøen char com-
burbot from Dudinka were similar to levels found in
pared with the Øyangen char. The largest concentration
burbot from Fairbanks and Yukon Flats, but DDT lev-
differences were found for the heavier PCB congeners,
els were higher. Information is lacking to completely
DDTs, and oxychlordane (Figures 4·27 and 4·28).
evaluate the Russian data.
There was no significant difference for HCHs. PCB
For the remaining lakes, with the possible exception
concentrations (seven congeners) in Arctic char were
of Lake Laberge, atmospheric deposition is the domi-
694 ng/g ww for fish from Ellasjøen and 49 ng/g ww for
nant route of OC delivery (Kidd et al., 1995). For these
fish from Øyangen. The congener pattern was generally
lakes, OC levels varied much less and were generally
similar for both lakes, with CB138 and CB153 having
within a factor of two of each other. The OC concentra-
the highest levels, followed by CBs 180, 118, 156, 105,
tions in burbot from these lakes are lower than those
and 101. However, CB138 co-eluted with CB160 and
previously reported for burbot collected from the
163, leading to an overestimation of this value. The
Mackenzie River in the Canadian Arctic in the 1980s
mean concentration of p,p'-DDE in char muscle tissue
(Muir et al., 1990a). For Canada, all of these sites are
was 57.7 ng/g ww in Ellasjøen and 3.4 ng/g ww in
fairly close to the Mackenzie, so the lower concentra-
Øyangen. Over 97% of the DDT in Arctic char from
tions in the recently collected burbot most likely reflect
Ellasjøen was p,p'-DDE. In Øyangen, the corresponding
temporal changes as opposed to spatial differences be-
number was 79%. The concentrations of chlordane,
tween the sites (see Section 5.3.3).
heptachlor, heptachlor epoxide, aldrin, and trifluralin
Burbot liver from northern Norway had TEQ levels
were below detection limits in almost all fish samples.
based on PCDD/Fs and non-ortho PCBs (see Annex
In 1999, small Arctic char (from 7- 64 g, presumed to
Table 16) of 12.8 pg/g ww (110 pg/g lw) (Schlabach et
be prey fish) from the two lakes (Ellasjøen and Øyangen,
al., 2001).
n = 3 for both lakes) were analyzed in order to supple-
ment the already analyzed material (consisting mostly of
Landlocked Arctic char
larger fish). In these smaller Arctic char, 15N values in
Landlocked char have been collected over a number of
Ellasjøen char were higher than in the char from Øyan-
years from lakes near the community of Qausuittuq
gen (average 17.42 and 8.65, respectively) but were
(Resolute) in the Canadian High Arctic (Muir et al.,
very similar to the larger Arctic char sampled previously
2001a). The effect of diet and trophic level on OC levels
for these two lakes. Not surprisingly, OC concentrations
was investigated using stable isotopes of carbon and ni-
were very different between the two lakes for the small
trogen. A few fish have 15N values that were up to 3.8
char but very similar to results in the larger char. The av-
parts per thousand () higher than others. This reflects
erage PCB7 concentration in small Arctic char from El-
differences in trophic level because concentrations of the
lasjøen was 642.7 ng/g ww (range 373.6 -906.6 ng/g
heavier isotope of nitrogen, 15N, are progressively en-
ww) and the corresponding value for small Arctic char
riched from prey to predator at an average of 3 to 5
from Øyangen was 37.1 ng/g ww (range 18.2-55.9 ng/g
(Peterson and Fry, 1987). Landlocked char populations
ww). For PCB, concentrations were 1139.1 ng/g ww
are known to develop a behavioral dichotomy wherein
(range 596.0 -1629.6 ng/g ww) for small Arctic char
some individuals at a certain `escape size' adapt to a can-
from Ellasjøen and 64.8 ng/g ww (range 32.2-97.5 ng/g
nibalistic feeding habit, while other individuals may not.
ww) for small Arctic char from Øyangen.
In Char Lake, a system containing only char, Hobson
In another study in Ellasjøen, Arctic char were found
and Welch (1995) associated 15N values of 13.7
to have PCDD/F and non-ortho PCB concentrations (see
with piscivory in char. They also found a significant in-
Annex Table 16) expressed as TEQs of 7.4 pg/g ww
crease in the 15N of these fish with size that they attrib-
(566 pg/g lw) (Schlabach et al., 2001). The PCBs con-
uted to cannibalism within the population. There were
tributed most to the TEQs.
no significant correlations of 15N with length or weight
Arctic char were sampled from a mountain lake in
in Resolute Lake char. PCB, DDT, and CHL concen-
the Faroe Islands in 2000 and 2001 (n = 25 and 40, re-
trations (lipid-normalized) were significantly correlated
spectively) and muscle tissue was analyzed for OCs
with 15N in char from Resolute Lake collected in 1997
(Hoydal et al., 2001). The single OC occurring with the
and 1999, suggesting that biomagnification of OCs is
overall highest concentration was p,p'-DDE, with a
occurring within the char population due to the presence
mean of approximately 1 ng/g ww in a char size group
of piscivorous char. These results support the hypothesis
of 36 -38 cm fork length. The next highest concentra-
(Muir et al., 2001a) that the reason for higher levels seen
tions were for HCB and CB153 at 0.9 ng/g ww for both.
in char sampled in 1993 in Char Lake was that piscivo-
Concentrations of CB153 and DDE increased with fish
rous char were analyzed.
length but HCB did not.
In 1998, dorsal axial muscle from landlocked (non-
Arctic char from a freshwater lake on the island of
anadromous) Arctic char from the lakes Ellasjøen and
Jan Mayen were analyzed for OCs (Gabrielsen et al.,
Øyangen (all caught in 1996) located on Bjørnøya, were
1997). The lake is near cliffs with nesting seabirds. The
analyzed for stable isotopes of nitrogen, PCBs, and a
char have relatively high liver concentrations of PCB
number of pesticides. An overview of the Bjørnøya lake
(155 ng/g ww) and DDT (71 ng/g ww), which may be
74
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
indicative of seabird guano inputs, similar to the situa-
areas. This region has a population of approximately
tion at Ellasjøen on Bjørnøya.
350 000 people but with minimal industrial activity. The
slimy scuplin is a non-migratory, bottom-feeding fish,
Faroe Islands brown trout
which makes it suitable for assessing levels of OCs in
In 1997, liver from landlocked brown trout (Salmo
sediment. OCs, including PCBs, were detected in just
trutta) were collected for OC analyses from two lakes
three samples from the 12 analyzed. DDE and DDT con-
(Fjallavatn and Leitisvatn) in the Faroe Islands (Larsen
centrations (whole body) of 9.0 and 6.1 ng/g were found
and Dam, 1999). Fish from Fjallavatn were combined
at one site; HCB concentrations of 5.7 ng/g at another;
into two pools, one containing the larger specimens
and, PCB concentrations of 79 ng/g at a third. These
(n = 9, mean length 28.6 cm) and one containing the
concentrations are low and in the range found for other
small individuals (n =19, mean length 23.4 cm). The
similar benthic fish from this region (see Annex Table 7
fish from Leitisvatn were of similar length but were
for other benthic species).
combined into two, mixed-size pools. HCB, p,p'-DDE
and trans-nonachlor were detected in the four liver
4.3.4. `New' chemicals in freshwater fish
pools at 0.5 ng/g ww, 3- 4 ng/g ww and at 1-2 ng/g ww,
respectively. For PCBs, only CBs 153, 138 (+163), and
There has been limited work on `new' chemicals in Arc-
180 were detected in all samples at approximately
tic freshwater fish and most of it has focused on PBDEs
2 ng/g ww, 1 ng/g ww and 1 ng/g ww, respectively.
(Annex Table 17).
These concentrations are similar to those observed
In the European Arctic, data are only available for
in Arctic char from the Faroe Islands (Hoydal et al.,
burbot and trout from northern Norway, and for Arctic
2001).
char from Ellasjøen on Bjørnøya (Schlabach et al.,
2001). Trout muscle PBDE levels (BDEs 47 and 99) are
Yukon River study
low at 0.10 - 0.36 ng/g ww (8-14 ng/g lw). Burbot liver
A number of fish species have been sampled and ana-
had PBDE levels (BDEs 47 and 99) of 20 ng/g ww (175
lyzed for OCs from headwater lakes in the Yukon River
ng/g lw). For both species, the PBDE levels are a factor
system since 1996 in response to detection of high con-
of 2 -10 times lower than PCB7 levels. The Arctic char
centrations of toxaphene (Palmer and Roach, 2001). Re-
at Bjørnøya have elevated levels of PBDE of 16.3 ng/g
sults for lake trout and burbot are covered previously in
ww (1250 ng/g lw), but these are a factor of 30 - 40 times
this section. OC concentrations in whitefish collected in
lower than PCB concentrations. The congener pattern
1998 from Lake Laberge are lower than those observed
in all three species is evenly distributed between BDE47
in lake trout on a wet weight basis but similar when con-
and BDE99, and resembles the PeBDE technical prod-
centrations are normalized to lipid content (Annex Table
uct. Measurable amounts of PCNs and SCCPs were also
7). OC concentrations in Lake Laberge are lower than
found in these fish. PCN concentrations were 8.6 -16
those observed in Watson Lake (collected in 1997 and
ng/g ww in trout muscle, 13 ng/g ww in Arctic char mus-
1998), although the Watson Lake whitefish are larger.
cle and 643 ng/g ww in burbot liver. SCCP concentra-
OC concentrations in inconnu collected from Peel River
tions were 3.3 ng/g ww in trout, 6.9 ng/g ww in Arctic
in 1999 are low compared to most other species of fish
char, and 38 ng/g ww in burbot.
from the Yukon region, but are similar to inconnu col-
PBDEs were measured in the livers of burbot col-
lected in Great Slave Lake in 1996 (Annex Table 7).
lected in the Mackenzie River (Canada) in 1988, 1999,
Concentrations of OCs in fish from the Yukon region
and 2000 as part of a project on temporal trends (Stern
are consistently below levels that result in any health ad-
et al., 2001a) (see Section 5.3.3). BDEs 47 and 99 were
visories (Palmer and Roach, 2001).
the predominant congeners in the burbot, but levels (< 2
ng/g lw per congener) were below those observed in the
Finnish Arctic fish
Norwegian fish (Annex Table 17). BDE congeners 100,
Recently a study was conducted on levels of OCs in the
153, and 154 were also detected in the burbot but at lev-
muscle tissue of four species of freshwater fish (Arctic
els lower than congeners 47 and 99.
char, northern pike, European perch (Perca fluviatilis),
and whitefish) in Finland (Mannio, 2002) (Annex Table
4.3.5. Bjørnøya lake study
7). A majority of OC concentrations were less than
1 ng/g ww, one to two orders of magnitude below con-
In 1994, an investigation of contaminants in sediments
centrations observed in similar species in the Canadian
and fish from Ellasjøen on the island of Bjørnøya was
Arctic. The lipid content of the muscle tissue of these
initiated (Evenset et al., 2002). This pilot study was
fish was very low (<1%), which explains some of the dif-
based on a very limited number of samples, but found
ferences with the Canadian samples. One group of
some of the highest PCB and DDT concentrations in
whitefish collected in the river Tornionjoki had much
freshwater sediments and fish ever seen in the Arctic.
higher OC concentrations than all other fish collected
Other studies from the same area have shown high PCB
from Finland (see Annex Table 7) but this was because
levels in glaucous gulls (Gabrielsen et al., 1995; Bust-
these fish were anadromous.
nes, 1998). In a follow-up study, the contamination
level in Ellasjøen was compared to Øyangen, another
Alaskan slimy scuplin
lake on Bjørnøya. Plankton, benthic animals and land-
Slimy sculpin (Cottus cognathus) from twelve locations
locked Arctic char from both lakes were analyzed for
within the Cook Inlet Basin were collected to assess lev-
contaminants and stable isotopes to provide informa-
els of OCs in this region (Frenzel, 2000). These twelve
tion on contaminant levels and bioaccumulation in the
locations included sites along roadways and in remote
food chain.
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
75
Bjørnøya
Barents Sea
Øyangen
Norwegian
Sea
Ellasjøen
Figure 4·26. The locations of
Bjørnøya, and the lakes El-
5 km
100 m contour intervals
lasjøen and Øyangen (from
Evenset et al., 2002).
Bjørnøya (74°30'N, 19°E) is situated halfway be-
The littoral zone in the northern part of the lake is also
tween the mainland of Norway and Svalbard (Figure
well developed but in the southern part it is very steep,
4·26). Bjørnøya has a surface area of 178 km2 and
and near the shore the depth is 15 to 20 meters.
measures 20 km from north to south. The annual aver-
The lake Skutilen is situated in the same catchment
age temperature is 3.8°C. Precipitation is low, with an
area as Ellasjøen. The lake has an area of 0.08 km2 and
annual rate of 367 mm (information from Det Norske
a maximum depth of 2 m. The primary outlet flows to
Meteorologisk Institutt). The southern part of the is-
Ellasjøen. Birds are seldom seen on Skutilen, but Arctic
land is mountainous with altitudes up to 536 m asl.
char have been observed in this lake. There is almost no
Seabirds breed on the steep cliffs along the south coast.
vegetation in the catchment area, except for some
The main species are common guillemot (Uria aalge),
mosses. The lake has no pelagic or profundal zone.
Brünnich's guillemot (Uria lomvia), kittiwake (Rissa
Øyangen (33 m asl) is situated on the central plains
tridactyla), little auk/dovekie (Alle alle), and glaucous
of Bjørnøya. The lake has an area of 0.35 km2 and a
gull. The terrain in most of the middle and north parts
maximum depth of 5 m. Most of the lake, however, is
of Bjørnøya is flat (30 - 40 m asl). The island has about
less than 1 m deep. The total catchment area is approxi-
740 lakes which cover 11% of the surface area. More
mately 2.2 km2, and the estimated retention time is 0.9
than 600 of these lakes are found on the central and
years. The area around Øyangen is very flat and consists
northern plains, and their depths seldom exceed 2 m.
mainly of boulders. On Øyangen, flocks of kittiwakes
Fewer than ten lakes reach depths between 5 and 10 m
can be observed, but the flocks are smaller and not seen
and these are found in the southern parts of the island.
as frequently as on Ellasjøen. There is almost no vegeta-
Ellasjøen is the deepest lake on the island (maximum
tion in the catchment area except for some mosses. The
depth of 34 m). Water temperatures are low, typically
lake has no pelagic or profundal zone, but Øyangen has
below 7°C in summer. There is no summer stratifica-
a population of landlocked Arctic char.
tion, but the lakes are cold monomictic (i.e. sub-polar).
The studies carried out in the limnic ecosystems on
The upper littoral zone generally comprises a rocky mar-
Bjørnøya have shown that Ellasjøen is significantly more
gin, 0.5-1 m deep.
contaminated by OCs than Øyangen (Figures 4 ·27 and
Ellasjøen, with an area of 0.72 km2 (21 m asl), is sit-
4 ·28), and that Ellasjøen has a higher `basic trophic
uated in the southern, mountainous part of Bjørnøya.
level' (Skotvold et al., 1999). Possibly, the higher `basic
The catchment area is 6.1 km2, and the lake has an esti-
level' of isotopes is caused by guano-input to the lake.
mated retention time of 6.5 years. In the southern part
Seabirds feed in the marine environment and may bring
of the catchment area (Alfredfjellet), there is a large
in nutrients (through guano) with different isotopic
colony of little auks. Large flocks of kittiwakes (hun-
composition than other nutrients that are transported to
dreds to thousands) can be observed on the lake during
the lake (i.e. runoff from land, decomposed material).
the summer period. At the outlet of the lake, there is a
Guano can also function as a transport medium for con-
colony of glaucous gulls (approximately 100 pairs). The
taminants from the marine environment to the limnic
birds present in the catchment area seem to have a large
environment in Ellasjøen. This theory was also sup-
impact on the lake, as indicated by the growth of green
ported by the fact that there was a similarity between the
algae on the shores directly below the colony. Mosses
CB99 : CB101 ratios in guano samples of seabirds and
and lichens occur around the northern and western
char from Ellasjøen, but none in char from Øyangen.
shore close to the lake, although in general, the catch-
Analysis of toxaphene congeners provided further evi-
ment area is devoid of vegetation. The lake has a very
dence of the influence of seabird guano. From the nine
well developed profundal and pelagic zone, and is in-
chorobornane congeners analyzed, only three, Parlars
habited by landlocked Arctic char (Klemetsen, 1985).
26, 40, and 50, were found in considerable amounts in
76
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
Concentration, ng/g ww
1.5
Øyangen
Sediment
1.0
Zooplankton
Chironomids
Arctic char
0.5
0
2.5
2.0
Ellasjøen
1.5
1.0
0.5
0
HCB
-HCH
-HCH
Dieldrin
Chlordane
Trifluralin
Heptachlor
-chlordane
-chlordane
-nonachlor
-nonachlor
Oxychlordane
cis
cis
trans
trans
Heptachlorepoxide
Figure 4·27. Concentrations of pesticides in sediment and biota from the lakes Ellasjøen and Øyangen on Bjørnøya (from Evenset et al., 2002).
Concentration, ng/g ww
30
Øyangen
Sediment
20
Zooplankton
Chironomids
Arctic char
10
0
313
226
80
Ellasjøen
70
60
50
40
30
20
10
0
'-DDE
'-DDE
'-DDD
'-DDD
'-DDT
'-DDT
CB101
CB105
CB118
CB138
CB153
CB156
CB180
o,p
p,p
o,p
p,p
o,p
p,p
Figure 4·28. Concentrations of DDT (including metabolites) and seven PCB congeners in sediment and biota collected from the lakes Ellasjøen
and Øyangen on Bjørnøya in 1996 (from Evenset et al., 2002). Note that CB138 may have co-eluted with CB160 and 163, inflating its value.
the analyzed biota samples from Bjørnøya. Levels found
siderably higher chlorobornane levels were found in
for all samples from Øyangen were very low, often not
biota samples from the Ellasjøen catchment area. Al-
exceeding the detection limits. The generally low levels
most no chlorobornanes were observed in zooplankton
found at Øyangen were consistent with low levels of
from Øyangen. In Ellasjøen, Parlar 50 concentrations of
PCBs found in this lake. As with the PCB results, con-
1.2 ng/g ww were found in zooplankton, and a signifi-
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
77
cant increase from zooplankton (sum of Parlars 26, 40
dian Arctic may be partly attributable to the influence of
and 50: 1.2 ng/g ww) to Arctic char (average sum of
local sources in the Yukon and the complete absence of
Parlars 26, 40 and 50: 8.1 ng/g ww) was found. Glau-
these sources in most of the High Arctic lakes.
cous gull gut from Ellasjøen had the highest toxaphene
The recent data for POPs in freshwater are too lim-
concentrations (sum of Parlars 26, 40, and 50: 84.2
ited to draw any additional conclusions about spatial
ng/g ww). Although significant differences were found
trends or the presence of new contaminants. Results
between Øyangen and Ellasjøen samples, the highest
from studies of Canadian Arctic lakes did provide new
chlorobornane concentrations, found in the pooled El-
information on degradation pathways of -HCH, indi-
lasjøen glaucous gull gut sample, cannot be considered
cating relatively rapid degradation compared to ocean
unusually high compared to published literature data
waters and an inverse relationship between enantioselec-
reported for Arctic marine top predators. A comprehen-
tive degradation and lake trophic status. These findings
sive review article presents levels up to 4000 ng/g ww
may be useful for interpreting the fate of other POPs in
(chlorobornanes) for marine mammals (de Geus et al.,
Arctic lake waters.
1999). However, based on the results of the present
There has been a considerable amount of research fo-
study, glaucous gull guano was identified as one of the
cused on OCs in Arctic freshwater biota since the first
major chlorobornane sources for the Ellasjøen freshwa-
AMAP POPs assessment, although less than that carried
ter system.
out in the marine environment. Similar to the terrestrial
The Bjørnøya lake study has highlighted the impor-
environment, levels of OCs in most freshwater biota of
tant influence of locally defined and restricted ecologi-
the Arctic are low compared with the marine environ-
cal, geographical, and meteorological environmental
ment but are similar to terrestrial predators. The excep-
factors on overall contaminant levels (e.g., precipitation,
tions are freshwater systems that receive additional POP
presence of local seabird nesting colonies, and resting
contamination via non-atmospheric routes. An excellent
areas). Based on these results, seabirds at Bjørnøya seem
example is the high levels of POPs found in the sediment
to function effectively as a transport link for POPs from
and biota of Ellasjøen on Bjørnøya. This lake receives a
the marine ecosystem to the freshwater ecosystem. It can
large amount of seabird guano, which is likely acting as
also be assumed that in other locations seabird guano
a vector to transport and concentrate POPs from the
may be a potential contamination source for persistent
marine environment and deposit them in a freshwater
pollutants, for example on Jan Mayen. Not only in Arc-
environment.
tic regions can such a seabird linkage between fresh-
Toxaphene and PCBs continue to be the predomi-
water and marine ecosystems result in elevated OC con-
nant OCs measured in freshwater biota, as was observed
centrations.
for Canada and Greenland in the first AMAP POPs as-
sessment. New data from Bjørnøya suggest that toxa-
phene is a major OC contaminant in freshwater inverte-
4.3.6. Summary and conclusions
brates and fish of the European Arctic. Toxaphene and
freshwater environment
PBDE were not found in Russian water or sediments,
The years 1996-2001 saw few new studies of POPs in
but the detection limits were above levels normally
river water in the Canadian Arctic, northern Norway or
found in the Arctic. PBDEs were found to be higher in
in northern Russia, although a major project was initi-
freshwater fish from Bjørnøya lakes and northern Nor-
ated in Russia in 2001-2002 to study contaminants in
way compared with fish from the Mackenzie River in
the rivers Yenisey and Pechora (RAIPON/AMAP/GEF
Canada. Levels were well below legacy OCs and lower
Project, 2001). However, results reported in the previous
than levels of PBDEs in marine biota. Lack of data on
AMAP POPs assessment were independently verified by
`new' chemicals, particularly perfluorinated compounds,
several researchers, confirming the original results and
is a significant gap for the freshwater environment.
deriving flux estimates for DDTs and HCHs. The flux
The Bjørnøya study and results from Alaskan and
estimates suggest that, at least until 1996, rivers such as
Russian burbot studies all highlight the potential for OC
the Ob and Yenisey contributed significant amounts of
levels to vary significantly between geographically close
DDTs and lindane to the Arctic Ocean, assuming that
locations. Elevated levels of OCs can occur due to local
what was measured at downstream sampling stations
point sources, although these are rare in the Arctic, or
was eventually carried to the northern Russian seas.
through unique ecological or biological scenarios. The
New measurements of OC pesticides and PCBs in
results of the Alaskan burbot study also highlight the
freshwater sediments were available for lakes in Canada,
importance of biological characteristics on fish OC lev-
on Svalbard and Bjørnøya, and on the Kola Peninsula.
els. Proper statistical analysis of spatial and temporal
The limited number of studies provided evidence for
trends of OCs in freshwater fish requires biological data,
contamination from both local sources and long-range
in particular size and age. Other factors, such as melt-
transport. In the case of Ellasjøen, levels of PCBs and
water from glaciers, may also influence OC levels in fish.
DDTs were up to ten times higher in its surface sedi-
PCB concentrations in many of the predatory fresh-
ments compared to Øyangen surface sediments due to
water fish of the Canadian, Russian, and Alaskan Arc-
inputs of seabird guano. This unusual input pathway was
tic, as well as fish from Ellasjøen on Bjørnøya exceeded
not important in Canadian Arctic lake sediments; how-
the most conservative guidelines for the protection of
ever, local sources from past uses of DDT, toxaphene,
aquatic wildlife of 15- 48 (Canada) to 160 (USEPA) ng/g
SCCPs, and PCBs were clearly important in explaining
ww (de March et al., 1998) (Table 6.1). Few fish ex-
some differences in fluxes of these compounds in Yukon
ceeded the U.S. guidelines. Information on the health of
lakes. The significant declining trend of PCBs and DDT
these fish populations is limited but there is no evidence
fluxes with latitude in lake sediments within the Cana-
to suggest that the populations are currently compro-
78
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
mised. No fish muscle samples were found to exceed the
of scientific cruises organized by circumpolar countries.
PCB guideline limit for human consumption and export
During this period, there were also several peer-reviewed
of fish of 2 µg/g ww, which is widely used in Europe and
publications on results of measurements of OCs in sea-
North America.
water pre-1996 (Rice and Shigaev, 1997; Hargrave et
Circumpolar trends of OCs in freshwater fish were
al., 1997; Jantunen and Bidleman, 1998; Strachan et al.,
evaluated using the Arctic char in the first AMAP assess-
2001); however, those results were included in the pre-
ment report (de March et al., 1998). Circumpolar OC
vious assessment (de March et al. 1998) and reviews
data for freshwater fish have not become available since
(Macdonald et al., 2000), and are included only for
that report, are not available even for Arctic char and, in
comparison here.
particular, are lacking for invertebrates. However, evalu-
The new measurements have, for the most part,
ation of OC levels in different species of predatory fish
been conducted from oceanographic research vessels in
suggest that concentrations of OCs in freshwater biota
a series of cruises (Figure 4 ·29). The Swedish Oden
of the circumpolar Arctic are similar with a few notable
cruise in 1996 conducted sampling from the ice edge to
exceptions (e.g., Ellasjøen on Bjørnøya), and lakes in the
the North Pole in the northern Barents Sea (Harner et
Yukon Territory in the western Canadian Arctic. New
al., 1999). In 1997, a Canadian supply trip (JOIS) for
data for OC concentrations in Russian freshwater fish
the Surface Heat Budget of the Arctic (SHEBA) study
are difficult to assess as little biological information is
(Perovich et al., 1999) was used to obtain seawater
available, but they suggest that some freshwater systems
from the western Canadian Arctic Archipelago in Sep-
of the Russian Arctic are among the most contaminated
tember. In May-June 1998, the Northwater Polyna
in the circumpolar Arctic (see Section 4.3.3.2). Slight
study in Northern Baffin Bay (NOW '98) provided an-
differences in OC levels of predatory fish within Great
other platform for sampling. In 1997-1998, the SHEBA
Slave Lake, one of the largest lakes within the Arctic,
study permitted continuous sampling of seawater over
provide evidence that abiotic environment and/or food
the Beaufort/Chukchi Seas. The Swedish Tundra North-
web characteristics can influence OC levels.
west study (TNW '99) traversed the Canadian Arctic
Archipelago during July/August, 1999. An Arctic to
Antarctic cruise by the RV Polarstern provided seawa-
4.4. Marine environment
ter samples from the East Greenland Sea in 2000 (La-
The marine environment has historically received the most
kaschus et al., 2002). Schultz-Bull et al. (1998) reported
attention with regard to OC and PAH contaminants in
PCBs in large-volume samples collected in the North
the Arctic environment. It was also the first Arctic sys-
Atlantic Ocean around Iceland which are also relevant
tem to be examined for the presence of OC contaminants
to this discussion and Sobek and Gustafsson (2002)
(Holden, 1970). The level of research on OC contamina-
presented preliminary results from the Oden cruise to
tion of the marine environment has continued to outdis-
the North Pole in 2001. Studies have also been con-
tance efforts in the freshwater and terrestrial Arctic. This
ducted in the Marginal Ice Zone of the Barents Sea
is clearly due to the higher levels observed in this system
north of Svalbard (Olsson, 2002) and in the Laptev Sea
and the role of marine organisms in the diet of northern
(Utschakowski, 1998).
populations. Since the first AMAP POPs assessment (i.e.
The new measurements have filled in some of the in-
post 1996), there has been a large amount of data pro-
formation gaps on spatial trends of OCs in the Arctic
duced for the marine environment, in particular for seals
Ocean. Sampling and extraction techniques were more
and whales, and a number of comprehensive studies on
uniform than in the 1980s and early 1990s, with large-
dynamics and mechanisms of OCs in this environment.
volume (20 to >100 L) samples collected and extracted
There have also been new initiatives to produce data for
using resin columns to minimize airborne contamina-
regions that were under-represented in the previous
tion. Some investigators used filtration (Harner et al.,
AMAP assessment, in particular the Alaskan and Rus-
1999) or continuous centrifugation (Strachan et al.,
sian Arctic.
2001) to remove particles; however, samples for HCH
This review and assessment of the post-1996 data
analyses were often unfiltered (Lakaschus et al., 2002).
will focus on persistent organohalogen compounds
HCH isomers were the most commonly measured chem-
(mainly OCs, as well as recent measurements of bromi-
icals in the Arctic Ocean and adjacent seas. These com-
nated and fluorinated organics and TBT). However,
pounds are present at ng/L concentrations and there are
PAHs are not included because sources in the aquatic
few problems with contamination on ships or in the lab-
marine environment are considered to be predominately
oratory. PCBs were the next most prominent contami-
of petrogenic origin (either from natural sources or an-
nants (Annex Table 8); however, there were far fewer
thropogenic uses) rather than from combustion and at-
measurements. PCB measurements in seawater are chal-
mospheric deposition sources (Robertson, 1998). A fu-
lenging because of low levels and potential for ship-
ture review of petrogenic PAHs will be conducted under
board as well as laboratory contamination. Comparison
the updated AMAP assessment of `petroleum hydrocar-
among different studies and with previous work on
bons' that is due to be published in 2006.
PCBs in Arctic and northern temperate seawaters (Iwata
et al., 1993; Schultz-Bull et al., 1998; Sobek and Gu-
stafsson, 2002) raises questions about contamination
4.4.1. Seawater
and the effects of different sampling techniques. These
4.4.1.1. Overview
include possible differences between whole (unfiltered)
A large number of measurements of OC pesticides and
water versus filtered samples, and the use of in situ col-
PCBs have been made in Arctic Ocean waters in the pe-
lection using remotely deployed samplers versus sub-
riod of 1996 to 2001 (Annex Table 8) mainly as a result
mersible pumping onto the ship.
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
79
HCH concentration
in surface seawater, ng/L
2
SHEBA '97-'98
1
JOIS '97
0
NOW '98
TNW '99
Figure 4·29. HCH in surface seawater from the
Arctic Ocean, 1996-2000, illustrating higher con-
Oden '96
centrations in the North American Arctic. Tracks
of oceanographic cruises are shown in blue.
Polarstern '00
ages on the order of 12-20 years, which coincides with
4.4.1.2. HCHs
the time of heaviest usage of HCH (Li et al., 1998a).
Harner et al. (1999) determined HCH isomers and ERs
Lakaschus et al. (2002) determined - and -HCH in
of -HCH in a large series of surface and deepwater
surface (11 m depth) seawater along an east-west tran-
samples from the northern Barents Sea and central Arc-
sect in the Greenland Sea. Concentrations in this region
tic Ocean (80-88°N, 11-143°E) (Annex Table 8). The
(HCHs = 0.57±0.20 ng/L east; 0.13-0.698 ng/L west)
mean concentrations for surface water were 1.18 ± 0.408
were similar to those in surface water and deeper water
ng/L for HCHs. These agreed well with measurements
in the Barents Sea (Harner et al., 1999), but two to four
by Strachan et al. (2000) on the same cruise and also
times lower than in the Beaufort Sea (Annex Table 8).
with values reported by Gaul (1992) for a 1985 survey
However, HCH concentrations in the Greenland Sea
of the northeast Atlantic (HCHs = 1.25 ng/L). Both -
(68-75oN) were three to five times higher than in the
and -HCHs increased with latitude between 74 -88°N
eastern Atlantic near the Bay of Biscay because of much
(r2 = 0.58 and 0.69 for - and -HCH, respectively).
higher levels of -HCH in Arctic waters (Lakaschus et
Values similar to those on the Oden cruise were found
al., 2002).
during 1994 in the eastern Arctic Ocean north of Spits-
HCH concentrations in the White Sea (Kanda-
bergen (HCHs = 1.17 ng/L) and in the Greenland Sea
lasksha Bay and central basin) in northwestern Russia
(HCHs = 0.83 ng/L) (Jantunen and Bidleman, 1996;
were similar to those in the Beaufort Sea (1.1 ± 0.11) and
1998).
two-fold higher than in the Barents Sea near Svalbard
Vertical profiles at 11 Oden cruise stations indicated
(Harner et al., 1999; Muir et al., 2002a). In general,
that concentrations at depths of 250 -1000 m were ap-
surface concentrations of HCHs are highest in the cen-
proximately 40% of surface values for -HCH and ap-
tral Canadian Arctic Archipelago, intermediate in the
proximately 60% for -HCH (summarized as HCHs
Beaufort/Chukchi Seas and at the North Pole, and low-
in Annex Table 8). Tracer studies in this region (Nansen
est in the Greenland Sea and northern Barents Sea (Fig-
Basin) indicate that the water masses at 250 -1000 m have
ure 4 ·29).
80
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
The large number of measurements of HCH during
during the sampling phase. Sampling on the SHEBA
the 1980s and 1990s in the Bering/Chukchi/Beaufort
study and nearshore samples at Barrow, Holman, and in
Seas, as well as in the Greenland Sea, also permits an ex-
the White Sea used in situ samplers (Axys Instruments,
amination of mass balances over time and temporal
Sidney BC) and GFF/XAD-2 resin deployed from ships
trends. These are discussed in Section 5.1. Other meas-
or through sea ice.
urements in the nearshore waters of the southern Beau-
The results in Annex Table 8 summarize the current
fort Sea also show higher HCH levels (Hoekstra et al.,
state of the art of PCB measurements in the Arctic
2002b) than in the eastern Canadian Arctic (northern
Ocean. Up to 100 PCB congeners were determined by
Baffin Bay).
some investigators; however, for this assessment results
The lowest HCH concentrations (mean 18 pg/L) were
for the sum of ten major PCB congeners were also in-
found by Utschakowski (1998) in seawater collected an-
cluded, where possible, to make comparisons more equi-
nually in the summers of 1993 to 1996 in the southern
table. Although all studies employed solid phase extrac-
Laptev Sea near the Lena River Delta. These concentra-
tion (mainly XAD-2 resin) for collection of PCBs, and
tions were lower than previously reported levels for the
followed strict protocols to avoid contamination, there
same region (20 -150 pg/L; de March et al., 1998).
is nevertheless major disagreement between measure-
-HCH, which is not as abundant in the Arctic abio-
ments, especially between those made using samples col-
tic environment, has not been as well studied. This is
lected with `Go-Flo' bottles or other large-volume con-
partly due to its low concentrations, which have posed
tainers and those with in situ or direct online sampling
analytical challenges. However, there is growing concern
of water. There are also major differences between re-
over its potential risks as it is the most bioaccumulating
sults for PCBs determined by in situ sampling with
of the HCH isomers and may be an environmental es-
`Axys' systems and the `Kiel' sampler.
trogen (Willett et al., 1998). Due to its greater water sol-
There are similar irreconcilable differences between
ubility (low Henry's law constant), -HCH is more effi-
results from Strachan et al. (2001) for the PCBs in the
ciently scavenged by rain and snow than -HCH and is
Bering Sea and results from Iwata et al. (1993) from the
preferentially deposited closer to the source regions in
Bering Sea (previously reported in the 1998 AMAP as-
high-precipitation areas in the northern North Pacific.
sessment). The latter study used GFF/PUF sampling from
Ocean currents then transport -HCH farther north
an online water system while the former used a sub-
into the Bering Sea through the Bering Strait (Li et al.,
mersible pump, a continuous centrifuge to separate par-
2002). Direct atmospheric transport of -HCH is a mi-
ticles and solvent extraction with dichloromethane. Iwa-
nor pathway. This means that, unlike -HCH, -HCH
ta et al. (1993) reported mean concentrations of 0.0084
concentrations in seawater peak in the Bering-Chukchi
ng/L at three locations in the Chukchi Sea and 0.012
region and then decrease northward into the Arctic
ng/L for four locations in the Bering Sea from their 1990
Ocean interior. This indicates that -HCH that was
cruise. Strachan et al. (2001) reported dissolved phase
maximally deposited in the North Pacific during 1970 -
concentrations averaging 1.0 ng/L in the Bering Sea
1985 is now entering the Arctic Ocean as a pulse to the
(seven sites) and means of 0.6 - 0.9 ng/L in the Chukchi
Bering Sea, delayed by some unspecified time, perhaps a
Sea. Given that both cruises covered the same area and
decade or more (Li and Bidleman, 2003).
sampled approximately the same depth, it is difficult to
attribute the differences except to contamination intro-
duced from the ship. The results of Iwata et al. (1993)
4.4.1.3. PCBs
for the Chukchi Sea are consistent with those of Sobek
After the HCHs, PCBs are the next most prominent
and Gustafsson (2002), Schultz-Bull et al. (1998), and
group of persistent OCs in Arctic seawater. As noted
Utschakowski (1998) in terms of the range of concentra-
above, comparison among different studies and with
tions but cannot be compared directly because of differ-
previous work on PCBs in the Arctic Ocean and nearby
ent numbers of congeners analyzed.
northern seas (Iwata et al., 1993; Schultz-Bull et al.,
With these caveats in mind we have limited the dis-
1998; Sobek and Gustafsson, 2002) raises important
cussion of results to data from Schultz-Bull et al. (1998),
questions about contamination and effects of different
Utschakowski (1998), Olsson (2002), and Sobek and
sampling techniques. Schultz-Bull et al. (1998) and
Gustafsson (2002); and to the `Axys' in situ sampler
Sobek and Gustafsson (2002) have reported concentra-
work conducted on the SHEBA study and in nearshore
tions of PCBs which are about ten times lower than
waters (Annex Table 8) recognizing that even the latter
other measurements summarized in Annex Table 8.
results may be confounded by contamination introduced
These latter groups have used ultra-clean techniques.
on handling and storage or in the laboratory.
Schultz-Bull et al. (1998) employed the `Kiel' in situ
There are too few PCB measurements to assess spa-
sampler, a remotely deployed filtration/extraction sys-
tial trends of PCBs, nevertheless some general conclu-
tem (Petrick et al., 1996) to sample large volumes of sea-
sions can be drawn from the data of Schultz-Bull et al.
water (230-1070 L) through glass fiber filters (GFF) and
(1998) and Sobek and Gustafsson (2002). PCB concen-
XAD-2 resin. Sobek and Gustafsson (2002) employed a
trations in the upper 50 m water column under the per-
stainless steel seawater intake system directly into the
manent ice cap are much lower (mean PCB10 =
Oden followed by on-line collection using GFF and
0.00055 ± 0.00043 ng/L) than in the northern North At-
polyurethane foam (PUF) in a `clean' room on board.
lantic (range 0.0014 - 0.0021 ng/L). Similar PCB con-
Seawater sampling on the earlier Oden, TNW, and
centrations (0.0016 - 0.0021 ng/L; dissolved + particu-
JOIST cruises for PCB analysis involved use of a stain-
late) were found in an ice-covered and a pelagic sam-
less steel lined `Go-Flo' bottle followed by GFF and
pling site in the marginal ice zone north of Svalbard
XAD-2 resin but did not employ clean room techniques
(Olsson, 2002). Somewhat higher PCB concentrations
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
81
(mean in the dissolved phase of 0.0034 ng/L (range
tamination they are internally consistent in that they
0.0001- 0.011 ng/L)) were found by Utschakowski (1998)
show a remarkable transition from the Canada Basin to
in the southern Laptev Sea near the Lena River Delta.
the Chukchi Plateau. East of the plateau (about 77°N,
Utschakowski (1998) found that PCBs were present at
160°W), the PCB profile consisted mainly of mono-, di-
similar concentrations in the particulate phase at this
and trichlorinated CB congeners (Figure 4 ·30 a). Over
location.
the southern edge of the Chukchi Plateau (April), the
In situ sampling during the SHEBA study (Macdon-
profile appears far more strongly influenced by the tech-
ald et al., 2001) and in nearshore waters (Hoekstra et
nical mixture component (Figure 4 ·30 b). As SHEBA
al., 2002b) also found higher PCB concentrations in
drifted back toward the interior ocean, the profiles in
nearshore waters of the Canadian Arctic Archipelago
July (Figure 4 ·30 c) and September (Figure 4 ·30 d) re-
and southern Beaufort Sea (PCB10 means of 0.040-
vealed a strengthened lower chlorinated PCB congener
0.060 ng/L). PCB10 levels in the central basin of the
profile. The PCB profile in waters west of the Chukchi
White Sea (0.028 ± 0.014 ng/L) were lower than in the
Plateau bore a greater resemblance to technical PCB
Canadian Arctic Archipelago, using the same sampling
mixtures such as the Russian `Sovol' (Schulz et al., 1989;
equipment and analytical techniques, despite the prox-
Ivanov and Sandell, 1992) (Figure 4 ·30 e) and Aroclor
imity of urban areas of Dvina Bay (eastern White Sea)
1254. Given the stratification of the water column and
and Kandalaksha Bay (western arm).
ice cover, these changes were not due to ice melt or bio-
Although the PCB measurements in the northern
logical processes. It seems much more plausible that the
Chukchi Sea (Figure 4 ·30) may be confounded by con-
PCB compositions along the track reflect the various
%
60
a
February
50
40
30
20
10
0
30
b
April
20
10
0
80
c
July
70
%
60
60
e
PCB technical mixtures
;
50
50
40
40
;
30
30
20
20
Sovol
;
;
;
1254
10
10
0
0
60
Cl 1-2
Cl 3
Cl 4
Cl 5
Cl 6
Cl 7
Cl 8
;;;
;
;;;
d
September
50
Depth, m
40
10
30
70
30
100
Figure 4·30. PCB congener distributions for the
130
150
20
vertical seawater profiles collected in February,
170
April, July, and September during the SHEBA
200
10
study. Also shown is a representative PCB dis-
250
tribution for the technical mixture Aroclor
0
1254 and the Russian formulation `Sovol'.
Cl 1-2
Cl 3
Cl 4
Cl 5
Cl 6
Cl 7
Cl 8
PCB homologue group
82
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
water masses through which SHEBA passed. The domi-
water in the North American Arctic were higher in
nant contribution from technical mixtures seen in April
northern Baffin Bay than in the southern Beaufort Sea
(Figure 4 ·30 b), strongly suggests that this profile has
(Hoekstra et al., 2002b). Lower toxaphene levels were
been imported from the Pacific Ocean/Bering Sea. The
found in seawater in the White Sea and in the northern
profiles collected in February, July, and September, on
Chukchi Sea than in the southern Beaufort Sea or north-
the other hand, probably reflect a stronger influence of
ern Baffin Bay (Annex Table 8). The recent measure-
Canada Basin interior water that has accumulated an
ments have included chlorobornane congeners, thus al-
important component of its PCB inventory from the at-
lowing some insights into the degradation of toxaphene.
mosphere. The inference to be drawn here is that PCBs
Levels of individual chlorobornanes are in the low pg/L
have been delivered via the Bering Sea in water directly
range (Figure 4 ·31). The congener profile of toxaphene
contaminated through, for example, runoff or spills,
in the Beaufort Sea was dominated by hexa- and hepta-
whereas the interior Arctic Ocean owes a significant
chlorobornanes, especially B6 -923 and B7-1001 (these
portion of its PCB content to condensation and/or
have no Parlar numbers). These are terminal residues
airsea exchange which favors the lighter components as
from dechlorination of many toxaphene congeners (Fin-
one progresses northward (Wania and Mackay, 1993;
gerling et al., 1996) and are prominent in lake water in
Muir et al., 1996a).
the Great Lakes (Muir et al., 1999a; Muir et al., 2001b).
The White Sea had a different congener pattern with un-
detectable levels of B6 -923 and more prominent octa-
4.4.1.4. Toxaphene
and nonachlorinated congeners. This pattern suggests a
Only a limited number of new measurements of tox-
fresher, less degraded source of the technical product.
aphene in seawater have been reported since the previ-
Polychlorocamphene or toxaphene was widely used in
ous AMAP POPs assessment, and they are too few to
Russian agriculture at least until the late 1980s (Mc-
fully assess spatial trends. Total toxaphene levels in sea-
Connell et al., 1996). Toxaphene was also present in se-
diments of a harbor area in Kola Bay (near Murmansk)
Concentration of toxaphene congeners
in surface seawater, pg/L
(Section 4.4.2) indicating other possible uses such as in-
sect control on ships (Savinova et al., 2000a).
12
White Sea
10
8
4.4.1.5. Other `legacy' OC pesticides
6
4
DDT and chlordane-related compounds, as well as
2
HCB were determined in several studies (Annex Table 8)
0
and were present at much lower concentrations than
toxaphene, PCBs or HCH isomers. Similar to the pat-
tern for PCBs, DDT residues were higher (by 5 to 20
times) in seawater from the Canadian Arctic Archipel-
ago and nearshore waters of the Beaufort Sea than over
50
the Chukchi Plateau or in the central Arctic Ocean.
CHL had a similar pattern although differences were
Southern Beaufort Sea
not as pronounced. This suggests that gas exchange and
melting are important sources for DDTs and CHLs.
40
Hargrave et al. (1997) found generally higher levels of
cis- and trans-chlordane and toxaphene under ice-cov-
ered conditions in the central Canadian Arctic Archipel-
ago compared to the open-water season. These authors
concluded that net deposition by seawaterair exchange
30
of toxaphene and chlordanes during the open-water pe-
riod was equivalent to 50 to more than 100% of the sur-
face layer inventory. Thus, lower concentrations of the
more hydrophobic OCs, such as PCBs and DDT under
20
the ice pack, are probably due to slow removal by sedi-
mentation and lack of resupply from the atmosphere.
DDT levels in White Sea seawater were lower than
in the southern Beaufort Sea or in the northern Barents
10
Sea (Annex Table 8). Despite possible ongoing use in
8
urban areas in the White Sea and Kola regions (Savinov
6
et al., 2003; AMAP, 2003), there was relatively little
4
spatial variation of DDT among ten sampling sites
2
0
(0.002-0.005 ng/L) ranging from Dvina Bay (eastern
White Sea) to the western end of Kandalaksha Bay
P-11 P-15
P-25
P-31
B6-923
B7-515
B8-789B8-531
B9-715
B7-1001
B8-1413
B8-1412
B8-2229
B9-1679
B9-1046
B9-1049
B9-1025
B9-2206
(western arm).
B10-1110
B8-806/809
Utschakowski (1998) found
B8-1414/1945
DDT concentrations
ranging from 0.0001 to 0.00178 ng/L in the dissolved
Figure 4·31. Comparison of mean (± SE) concentrations (ng/L) of
individual toxaphene congeners in surface waters from the White
phase and from 0.00036 to 0.00087 ng/L on particles in
Sea (n = 5) and the southern Beaufort Sea (Hoekstra et al., 2002b).
seawater from the southern Laptev Sea collected in 1993
4.4.1.4.1
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
83
to 1994. The DDT residues in this region were predomi-
Depth, m
nately in the form of p,p'-DDE.
0
Macdonald et al. (2001) reported on the vertical dis-
a DDT
tribution of DDT, dieldrin and chlordane over the
50
Canada Basin and Chukchi Plateau (Figure 4 ·32 a-c) as
part of the SHEBA study. The vertical distributions of
100
these OC pesticides were very different from those ob-
served for the HCHs where concentrations are found to
150
decrease from their highest values near the surface to
very low values below depths of 200-300 m. This may
have been due to changes in water mass. Taking DDT as
200
September
April
perhaps the best example, however, it seems likely that
July
February
there is also a seasonal signal related to the biological
250
cycle. In April and February of 1998, the DDT profiles
were somewhat noisy, but reasonably uniform at about
0
2 pg/L through the water column down to 250 m (Figure
4 ·32 a). By July, however, this uniformity was disrupted,
b Dieldrin
with much lower DDT concentrations evident in the
50
top 100 -150 m of the water column and higher concen-
trations at about 200 -250 m. In September, the surface
100
concentrations of DDT were again uniform at about 2
pg/L, but higher concentrations are evident at or below
150
approximately 150 m. Although water mass changes
may contribute partly to the observed behavior, there
200
appears also to be a transfer of DDT from surface to
July
February
April
deeper waters in spring when biological production pro-
September
250
duces a vertical flux of organically rich particles.
0
4.4.1.6. Current-use chemicals
c Total chlordane
Endosulfan and lindane ( -HCH) are the only pesticides
50
in current use in circumpolar countries that are reported
to date in Arctic Ocean water. Levels of lindane are gen-
100
erally highest in the Canadian Arctic Archipelago and
southern Beaufort Sea, and lowest in the central Arctic
Ocean (Strachan et al., 2000), over the Chukchi Plateau
150
and in the White Sea. Lakaschus et al. (2002) found lin-
dane concentrations in the North Sea (0.33 ng/L) within
200
September
February
the range of concentrations observed in the Greenland
July
Sea (0.072- 0.50 ng/L). White Sea waters were character-
250
April
ized by higher -HCH than in the Barents Sea, reflecting
use in urban areas within the watershed. Within the White
0
5
10
15
20
Concentration in seawater, pg/L
Sea, higher lindane concentrations were found in Kanda-
laksha Bay (0.19- 0.41 ng/L) compared with the Central
Figures 4·32. Vertical profiles of `legacy' OC pesticides (DDT, diel-
Basin (0.16 - 0.37 ng/L) (Muir et al., 2002a). However, in
drin, and chlordane) in seawater sampled during four intervals
(February, April, July, and September) over the Canada Basin and
general, -HCH levels in the White Sea were lower than
Chukchi Plateau (see Figure 4·30) in 1998 (Macdonald et al., 2001).
those in the southern Beaufort Sea. / -HCH ratios aver-
aged 1.8 ± 0.05 in the White Sea, compared with 2.2
Chlorobenzenes are prominent contaminants in Arc-
± 0.52 in the Greenland Sea, 3.4 ± 0.77 in the northern Ba-
tic seawaters; however, the number of measurements of
rents Sea/central Arctic Ocean, and 2.3 ± 0.77 in the Beau-
chlorobenzenes is limited. Di- to hexachlorobenzenes
fort Sea (Hoekstra et al., 2002b; Macdonald et al., 2001).
have been reported (Strachan, 2002). HCB concentra-
Endosulfan is a widespread contaminant in Arctic
tions appear to be relatively uniform compared to other
seawater although present at much lower levels than lin-
compounds. Concentrations ranged from 0.006 ng/L in
dane. Endosulfan (sum of - and -isomers) concentra-
the southern Beaufort Sea to means of 0.005 ng/L in the
tions ranged from < 0.0005 to 0.003 ng/L with no clear
White Sea. There are no data for chlorobenzenes in sea-
spatial trends. Hargrave et al. (1997) found endosulfan
water from the European Arctic except for the White
concentrations were higher during open water periods in
Sea (Annex Table 8).
the central Canadian Arctic Archipelago reflecting in-
puts from gas exchange and freshwater. During a twelve
4.4.1.7. Modeling latitudinal trends of -HCH
month study in 1993, endosulfan concentrations in-
in ocean waters
creased three-fold during the late summer and autumn
months, paralleling increasing air concentrations. This
It is of particular interest, from an Arctic perspective, to
was possibly related to summer use of endosulfan in
examine the global fate of -HCH. By the 1990s, the
mid-latitude North America.
concentration levels in the Canadian Arctic Ocean were
84
AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic
-HCH, observed concentration in seawater, pg/ L
Predicted concentration, pg/ L
1000
1000
1987
1989
1991
1993
1997
1999
100
100
10
10
a
b
0
0
80°N
60°N
40°N
20°N
0
20°S
40°S
60°S
80°S
80°N
60°N
40°N
20°N
0
20°S
40°S
60°S
80°S
Latitude
Latitude
Figure 4·33. Latitudinal trends in a) observed and b) predicted seawater concentrations of -HCH in the Atlantic Ocean (Lakaschus et al.,
2002). Concentrations were predicted with the `Globo-POP' model of Wania and Mackay (2000).
higher than anywhere else in the global marine environ-
model also suggested that ocean currents are as impor-
ment, notably an order of magnitude higher than in the
tant in the northbound transport of -HCH as the at-
Indian Ocean and the western Pacific, which are much
mosphere. Most of the -HCH in the Arctic originated
closer to the major source regions (lwata et al., 1993;
in the northern temperate zone, which also was a net ex-
Wania and Mackay, 1996; de March et al., 1998). -
porter of -HCH to low latitudes. While -HCH accu-
HCH, the major component of technical HCH, was
mulated in the north, it was rapidly degraded under tropi-
used in massive quantities in Asia during the 1970s.
cal conditions. Comparisons showed that calculated and
There has been a steady decline in use since then, and it
measured -HCH concentrations in the atmosphere and
is now virtually out of use worldwide (Li et al., 1996;
seawater generally agree within an order of magnitude
1998a; Li 1999a; 1999b). Compared to most other OC
(Wania et al., 1999a; Lakaschus et al., 2002) (Figure
pesticides, it is relatively water-soluble, relatively vola-
4 ·33). Deviations are due to the zonal averaging charac-
tile, and less persistent. Calculations using the `Globo-
teristics of the model and uncertainties associated with
POP' global distribution model (Wania and Mackay,
the environmental degradation rates of -HCH.
2000) suggested that this inverted latitudinal concentra-
tion gradient developed during the two decades of de-
4.4.2. Marine sediments
clining emissions and was the result of -HCH being
trapped and preserved in the cold Arctic Ocean, whereas
The previous AMAP assessment report presented a
the levels in source regions declined as a result of degra-
large dataset on PCBs, DDTs, HCB, and HCHs in
dation and volatilization. This is illustrated in Figure
marine sediments based on results from the early 1990s
4 ·33. Thus, the Arctic Ocean constitutes the last global
(de March et al., 1998). Those results showed relatively
refuge of -HCH (Macdonald et al., 2000). Interest-
uniform low levels of OCs in marine surface grab sam-
ingly, this highlights the fact that inverted concentration
ples (all concentrations <10 ng/g dw). Thus, a general
gradients can be established even if only a small percent-
understanding of the distribution of the different con-
age of the globally emitted amount is transferred to
taminants in the Arctic was established during AMAP
Arctic latitudes. In fact, the model predicted that the
Phase I. No widescale regional geographic trends were
bulk of the -HCH never left the agricultural systems in
apparent. However, there were distinct differences be-
which it had been applied. Relatively small amounts can
tween nearshore and offshore sampling sites especially
result in high concentrations in the Arctic because of the
in Norway, which pointed to the need for further un-
relatively small size of the Arctic as a whole and of the
derstanding of `hot spots' and their importance as a
environmental phases with high capacity for adsorbing
source for contamination of adjacent areas. Previous
hydrophobic organic chemicals (organic soils, vegetation,
studies in the Canadian Arctic have identified harbors
organic sediments) within the Arctic. By binding sub-
in communities with military radar bases as having
stances such as HCH, these phases reduce the amount
higher PCB concentrations in sediment (Bright et al.,
present in the atmosphere and in aquatic systems. The
1995b).
Chapter 4 · Regional and Circumpolar Levels and Trends in Abiotic and Biotic Media
85
Svalbard
DDTs were present at similar levels as PCBs with
POPs were determined in surficial sediments collected
highest levels at the deep site (0.62 ng/g dw). DDE pre-
in the Svalbard area of the Barents Sea in 1997 (Akva-
dominated at the deep site, while higher proportions of
plan-niva, 1998). Sampling sites included Kongsfjor-
DDT and DDD isomers were found in most nearshore
den (western Svalbard), Questrenna (north of Sval-
samples, suggesting some past use of DDT on Svalbard.
bard), Lomfjorden and Hinlopen Strait (northern Sval-
bard), Erik Eriksen Strait (eastern Svalbard), and Stro-
Northern Norway/Kola Peninsula and the White Sea
fjorden (southern Svalbard) (Figure 4·34). The samples
A study was conducted of OCs in sediments from six
were from relatively deep stations offshore (56 -363 m
harbors in northern Norway and northwest Russia, an
depth, and 2224 m at Questrenna) and did not include
area that has been determined to be a key monitoring
harbor areas. PCB levels were very low, ranging from
area by AMAP. The results allowed comparison of con-
0.025 to 0.61 ng/g dw (sum of seven congeners mul-
centrations and the composition of congeners of the dif-
tiplied by two to estimate total PCBs). Levels were sim-
ferent OCs in the two countries (Dahle et al., 2000).
ilar to those reported around Franz Josef Land (Killie
When comparing the results for the six different har-
et al., 1997; de March et al., 1998). The deep sediment
bors, some differences in study set-up should be noted.
sample (Questrenna) had higher concentrations than
The most polluted areas in the Norwegian harbors were
other sites and a distinctly different PCB pattern, with
generally known, and the stations were positioned in
higher proportions of hepta- and octachlorinated bi-
order to confirm the local `hot spots' and to check the de-
phenyls. No influence on samples was evident from
gree to which contaminants had been spread to other parts
possible local PCB sources in harbors of towns on Sval-
of the harbor areas. The study in the Russian harbors was
bard.
a screening study based on a limited number of stations.
10°E
20°E
25°E
30°E
PCB concentration
HCB concentration
HCH concentration
in sediment,
in sediment,
in sediment,
ng/g dw
ng/g dw
ng/g dw
0.5
0.2
1.0
81°N
0
0
0
78°N
DDT concentration
CHL concentration
in sediment,
in sediment,
ng/g dw
ng/g dw
0.5
0.1
0
0
Figure 4·34. PCB, HCB, HCH, DDT,
and CHL concentrations in surface sedi-
ment samples collected in 1997 from around
Svalbard.