Assessment of legacy and emerging persistent organic pollutants in Weddell seal tissue (Leptonychotes weddellii) near McMurdo Sound, Antarctica (original) (raw)
Related papers
2012
Muscle samples were collected from pup, juvenile and adult Weddell seals (Leptonychotes weddellii) near McMurdo Sound, Antarctica during the austral summer of 2006. Blubber samples were collected from juvenile and adult seals. Samples were analyzed for emerging and legacy persistent organic pollutants (POPs) including current and historic-use organochlorine pesticides, polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs). Of the 41 target analytes, 28 contaminants were recovered from the Weddell seal blubber, in this order of prevalence: p,p′-DDE, p,p′-DDT, trans-nonachlor, mirex, cis-nonachlor,
Bioaccumulation of PCBs, OCPs and PBDEs in Marine Mammals From West Antarctica
Frontiers in Marine Science, 2021
To understand the bioaccumulation and food web dynamics of persistent organic pollutants (POPs) as a function of species, age and sex in Antarctic mammals, blubber samples of 3 killer whales (Type C) and 77 pinnipeds (Weddell, Ross and crabeater seals) were collected from the Southern Ocean, Antarctica. They were analyzed for polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs). DDTs, 29 PCBs and chlordanes (12-4,600, 13-1,600, and < 1.5-1,700 ng/g lipid, respectively) were the most abundant POPs. Killer whales typically displayed several times greater concentrations of POPs compared to seals, except for PBDEs. PCBs and PBDEs were consistently higher in adult crabeater and Weddell seal males, and in adult female Ross seals than in other sex and age groups reflecting an age accumulation and possible influence of segregated diet, foraging areas, and metabolic transformation rates. POPs concentrations significantly correlated with gene transcription of nuclear receptors involved in detoxification of contaminants and immune relevant cell mediators in the crabeater seals, indicating possible immunotoxic and deleterious health effects. This represents one of the largest studies on POPs in Antarctic marine predators and highlights the complexity of POPs bioaccumulation.
PBDEs in serum and blubber of harbor, grey and harp seal pups from Eastern Canada
Chemosphere, 2011
Serum and blubber of pup harbor (Phoca vitulina), grey (Halichoerus grypus) and harp (Phoca groenlandica) seals from the Estuary and the Gulf of St. Lawrence were analyzed for polybrominated diphenyl ethers (PBDEs). Concentrations of P PBDEs (on lipid weight basis) in tissues of harbor seal pups inhabiting the St. Lawrence Estuary were about five times higher than in those from a colony located in the northern Gulf. Harp seal pups have the lowest levels of P PBDEs among the seal species born in the Gulf of St. Lawrence. Lipid normalized concentrations of P PBDEs in serum and blubber were strongly correlated, suggesting that the blood collection as a less invasive method could be used to monitor P PBDEs in pups. This study shows that fluvial inputs of PBDEs are important to the St. Lawrence marine ecosystem and that inhabiting harbor seal pups have a substantial exposure to PBDEs at a critical developmental stage. In addition, the observed difference in PBDE levels between harp and grey or harbor seal pups from the Gulf of St. Lawrence is explained by the difference in diets of their mothers which is linked with their residency time in the Gulf and their seasonal migration pattern.
Chemosphere, 2005
Blubber samples from grey seal (Halichoerus grypus) pups were collected in 1998 through to 2000. Twenty four newly weaned pups were sampled in November 1998, 13 of which were re-sampled during their first year of life, between March and December 1999, and an additional 48 and 25 samples (new cohorts) were obtained in 1999 (November-December) and 2000 (May-September) respectively. P PBDE concentrations (sum of Di-HxBDEs) ranged from 45 to 1500 ng/g lipid, with a geometric mean of 290 ng/g lipid. BDE 47 dominated the congener profile, followed by BDEs 100, 99, 153 and 154. P PCB concentrations (sum of 41 congeners) ranged from 100 to 93 000 ng/g lipid, with a geometric mean of 4600 ng/g lipid, with CB congeners 153, 138 and 180 making up 84% of the total PCB concentrations. The predominant OC pesticides were p,p 0 -DDE (geometric mean = 860 ng/g lipid, range = 160-3800 ng/g lipid) and p,p 0 -DDT (geometric mean = 120 ng/g lipid, range = 30-670 ng/g lipid). No significant differences were found between males and females, probably due to the young age of the animals. Significant decreases (P < 0.01 for PBDEs and P < 0.05 for PCBs/OCs) were observed between newly weaned seals in 1998 and 1999, but not for the majority of juveniles in 1999 and 2000. Significant differences (P < 0.01) were also found between the different seasons in 1999 newly weaned and juvenile seals, reflecting changes in blubber mass.
Environmental Science & Technology, 2011
Concentrations of hexabromocyclododecane (HBCD) were determined in a combination of archived and fresh blubber samples of juvenile ringed seals from East Greenland collected between 1986 and 2008. R-HBCD was the only diastereoisomer consistently above levels of quantification and showed a significant log-linear (exponential) increase from 2.0 to 8.7 ng/g lipid weight (median concentrations) with an annual rate of þ6.1%. The concentrations were up to several orders of magnitude lower than those reported for marine mammals from industrialized areas. Previously presented time trends on polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) have been extended with new data for 2006 and 2008. ΣPBDE in juvenile seals was the only parameter with a slight upward trend, however, dependent on the low 1986 concentration. Removing this data point resulted in a downward trend, which also was found for adult seals with a time trend starting in 1994. ΣPCB decreased significantly in juvenile seals, again due to the 1986 value, while no trend was found for the adult animals. This indicates stagnating PCB concentrations at a relatively high level, in some cases possibly exceeding tolerable daily intake rates for seal blubber as traditional Arctic food items.
Environmental Science & Technology, 2009
The present study investigated the concentrations and patterns of PBDEs and hydroxylated (OH) PBDE analogues in two ringed seal populations: less contaminated Svalbard and more contaminated Baltic Sea. Mean concentration of hepatic Σ-PBDE, which was dominated by BDE47, was six times higher in the ringed seals from the Baltic Sea compared to the seals from Svalbard. BDE47/Σ-PBDE was higher in the seals from Svalbard compared to that for Baltic seals, while the trend was opposite for BDE153 and 154. The geographical difference in contaminant pattern of PBDEs in ringed seals could be explained by biotransformation via oxidative metabolism and/ or by dietary differences. OH-PBDEs were detectable in the majority of plasma samples from both locations, and dominated by bioaccumulation of naturally occurring congeners. Low levels of 3-OH-BDE47 and 4′-OH-BDE49 in the Baltic ringed seals suggested minor oxidative biotransformation of BDE47. In the Baltic seals, BDE153/Σ-PBDEs and BDE154/Σ-PBDEs increased and BDE28/Σ-PBDE decreased with increasing Σ-POP concentration, which suggests BDE153 and 154 are more persistent than BDE28. Contrasting diets of the ringed seals in these two locations may influence the PBDE congener pattern due to selective long-range transport and direct effluent emissions to Svalbard and the Baltic, respectively.
Temporal Variation of PCDDs, PCDFs and PCBs in Baikal Seals (Pusa sibirica
This study investigated accumulation features and temporal trends of dioxins and related compounds (DRCs), such as PCDD/Fs, dioxin-like PCBs (DL-PCBs), and non dioxin-like PCBs (NDL-PCBs) in the blubber of Baikal seals collected in 1992 and 2005. PCBs including DL-and NDL-congeners were dominant. Concentrations of PCDD and PCB congeners in males were significantly higher than in females. However, such a trend was not observed for PCDFs. In males, age-dependent accumulations were observed for PCDD, mono-ortho PCB and NDL-PCB congeners. PCDFs and non-ortho PCBs showed no such trend, implying that exposure of seals to these contaminants has been decreasing in recent years. No decreasing temporal trend was observed for PCDDs, mono-ortho PCBs and NDL-PCBs, suggesting that Baikal seals are still exposed to relatively high levels of PCDDs and PCBs. TEQs of PCDDs and mono-ortho PCBs in seals collected in 2005 were within 62-77% of total TEQs. The TEQ levels in 40% of the specimens exceeded the threshold level for immunosuppression observed in harbor seals.
Contaminant levels in the world's northernmost harbor seals (Phoca vitulina)
Marine pollution bulletin, 2014
The world's northernmost harbor seal (Phoca vitulina) population, which inhabits Svalbard, Norway, constitutes a genetically distinct population. The present study reports concentrations of 14 PCBs, 5 chlordanes, p,p'-DDT, p,p'-DDE, hexachlorobenzene (HCB), mirex, and, α-, β-and γ-hexachlorocyclohexane (HCH) in blubber, and pentachlorophenol, 4-OH-heptachlorostyrene, 10 OH-PCBs and 14 perfluoroalkyl substances in plasma of live-captured harbor seals from this population (4 males, 4 females, 4 juveniles), sampled in 2009-2010. Concentrations of PCB 153, p,p'-DDE, oxychlordane, α-HCH and mirex and perfluoroalkyl sulfonates in Svalbard harbor seals were considerably lower than harbor seal from more southerly populations, while concentrations of HCB, OH-PCBs and perfluoroalkyl carboxylates were similar for harbor seals from Svalbard and southern areas. Concentrations of PCBs and pesticides in the Svalbard harbor seals were 60-90% lower than levels determined a decade ago...
Environment International, 2009
We report on the comparative bioaccumulation, biotransformation and/or biomagnification from East 28 Greenland ringed seal (Pusa hispida) blubber to polar bear (Ursus maritimus) tissues (adipose, liver and 29 brain) of various classes and congeners of persistent chlorinated and brominated contaminants and 30 metabolic by-products: polychlorinated biphenyls (PCBs), chlordanes (CHLs), hydroxyl (OH-) and 31 methylsulfonyl (MeSO 2-) PCBs, polybrominated biphenyls (PBBs), OH-PBBs, polybrominated diphenyl ether 32 (PBDE) and hexabromocyclododecane (HBCD) flame retardants and OH-and methoxyl (MeO-) PBDEs, 2,2-33 dichloro-bis(4-chlorophenyl)ethene (p,p′-DDE), 3-MeSO 2-p,p′-DDE, pentachlorophenol (PCP) and 4-OH-34 heptachlorostyrene (4-OH-HpCS). We detected all of the investigated contaminants in ringed seal blubber 35 with high frequency, the main diet of East Greenland bears, with the exception of OH-PCBs and 4-OH-HpCS, 36 which indicated that these phenolic contaminants were likely of metabolic origin and formed in the bears 37 from accumulated PCBs and octachlorostyrene (OCS), respectively, rather than being bioaccumulated from a 38 seal blubber diet. For all of the detectable sum of classes or individual organohalogens, in general, the ringed 39 seal to polar bear mean BMFs for ΣPCBs, p,p′-DDE, ΣCHLs, ΣMeSO 2-PCBs, 3-MeSO 2-p,p′-DDE, PCP, ΣPBDEs, 40 total-(α)-HBCD, ΣOH-PBDEs, ΣMeO-PBDEs and ΣOH-PBBs indicated that these organohalogens bioaccumu-41 late, and in some cases there was tissue-specific biomagnification, e.g., BMFs for bear adipose and liver 42 ranged from 2 to 570. The blood-brain barrier appeared to be effective in minimizing brain accumulation as 43 BMFs were ≤ 1 in the brain, with the exception of ΣOH-PBBs (mean BMF = 93 ± 54). Unlike OH-PCB 44 metabolites, OH-PBDEs in the bear tissues appeared to be mainly accumulated from the seal blubber rather 45 than being metabolic formed from PBDEs in the bears. In vitro PBDE depletion assays using polar bear hepatic 46 microsomes, wherein the rate of oxidative metabolism of PBDE congeners was very slow, supported the 47 probability that accumulation from seals is the main source of OH-PBDEs in the bear tissues. Our findings 48 demonstrated from ringed seal to polar bears that organohalogen biotransformation, bioaccumulation and/ 49 or biomagnification vary widely and depended on the contaminant in question. Our results show the 50 increasing complexity of bioaccumulated and in some cases biomagnified, chlorinated and brominated 51 contaminants and/or metabolites from the diet may be a contributing stress factor in the health of East 52 Greenland polar bears.
Accumulation features and temporal trends of PCDDs, PCDFs and PCBs in Baikal seals ( Pusa sibirica
Environmental Pollution, 2009
This study investigated the accumulation features and temporal trends of PCDD/Fs, dioxin-like PCBs (DL-PCBs) and non-dioxin-like PCBs (NDL-PCBs) in the blubber of Baikal seals collected in 1992 and 2005. DL-PCBs (480-3600 ng/g) and NDL-PCBs (980-35,000 ng/g) were dominant contaminants. Concentrations of PCDDs and PCBs in males were significantly higher than in females. In males, age-dependent accumulation was observed for PCDDs, mono-ortho PCBs and NDL-PCBs. PCDFs and non-ortho PCBs showed no such trends, implying that exposure of seals to these contaminants has been decreasing in recent years. No decreasing temporal trend was observed for PCDDs, mono-ortho PCBs and NDL-PCBs, suggesting that Baikal seals are still exposed to PCDDs and PCBs. TEQs of PCDDs and mono-ortho PCBs in seals collected in 2005 accounted for 62-77% of total TEQs. The TEQ levels in 40% of the specimens exceeded the threshold level for immunosuppression observed in harbor seals (209 pg/g).