Legacy contaminants in the eastern Beaufort Sea beluga whales ( Delphinapterus leucas ): are temporal trends reflecting regulations?

Arctic Science

article

Marie Noël¹  Lisa L. Loseto²  Gary Stern³ 

[1] Ocean Pollution Research Program;Freshwater Institute/Fisheries and Oceans Canada, 501 University Cres.;Department of Environment & Geography, University of Manitoba, 500 University Cres.

关键词: PCBs;    DDT;    HCH;    Inuvialuit settlement region;    beluga whale.;   

DOI  :  10.1139/as-2017-0049

学科分类：地球科学(综合)

来源: NRC Research Press

【 摘 要 】

Once deposited onto Arctic ecosystems, persistent organic pollutants (POPs) biomagnify in foodwebs such that relatively high levels have been detected in predators like beluga whales ( Delphinapterus leucas ). Our study aimed at assessing temporal trends of legacy POPs in eastern Beaufort Sea beluga blubber collected during traditional harvests in the Mackenzie Estuary area, Northwest Territories. Concentrations of polychlorinated biphenyls (PCBs) and 14 pesticides were quantified in 185 blubber samples collected between 1989 and 2015. The majority of legacy POPs analyzed showed no significant changes during the study period (ΣPCBs, Σchlordanes, Σdichlorodiphenyltrichloroethane, hexachlorobenzene, dieldrin, and mirex) and, therefore, did not reflect regulations put into place over the past decades. Although α- (82.6 ± 12.6 and 15.9 ± 1.9 ng/g in 1989 and 2015, respectively) and γ-hexachlorocyclohexane (γ-HCH) (126.6 ± 23.9 and 13.9 ± 0.9 ng/g, respectively) showed significant decrease between 1989 and 2015, β-HCH showed a more complex trend with concentrations increasing between 1989 (71.2 ± 13.4 ng/g) and 2004 (276.8 ± 13.5 ng/g) before decreasing until 2015 (174.7 ± 8.3 ng/g). Differences in trends likely reflect physico-chemical properties affecting transport to the Arctic. With climate change and melting sea ice potentially affecting the transport and release of legacy POPs, continuous monitoring is necessary.

【 授权许可】

CC BY