title: PBDE flame retardants and PCBs in migrating Steller sea lions (Eumetopias jubatus) in the Strait of Georgia, British Columbia, Canada.
abstract: Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were measured in blubber biopsy samples from 22 live-captured Steller sea lions (Eumetopias jubatus) that had just entered the Strait of Georgia, British Columbia, Canada, for their overwintering feeding season. ∑PBDE ranged from 50μgkg(-1) (lipid weight) in adult females to 3780μgkg(-1) in subadult individuals. ∑PCBs ranged from 272μgkg(-1) in adult females to 14280μgkg(-1) in subadult individuals. While most PBDE and PCB congeners were transferred through milk to pups, PCBs with logK(OW)>7.0 (PCBs 206, 207, 208 and 209) appeared constrained, resulting in a lighter mixture in pups compared to adult females. The ratio of individual PCB congeners by metabolic group (Groups I, II, III, IV and V) to PCB-153 regressed against length of males suggested poor biotransformation of these compounds (slopes did not differ from zero, p>0.05). PBDE congeners 49, 99, 153 and 183 appeared bioaccumulative (slopes of ratio BDE/PCB 153 versus length were higher than zero, p<0.05), but the dominance of the single congener, BDE-47 (64% of total PBDEs), likely due in part to debromination pathways, reduced our ability to explore congener-specific dynamics of PBDEs in these pinnipeds. With 80% of our Steller sea lions exceeding a recent toxicity reference value for PCBs, the fasting-associated mobilization of these contaminants raises concerns about a heightened vulnerability to adverse effects during annual migrations.
authors.affiliation: School of Resource and Environmental Management, Faculty of Environment, Simon Fraser University, Burnaby, BC, Canada V5A 1S6. jalavasa@sfu.ca
authors.forename: Juan José
authors.initials: JJ
authors.lastname: Alava
authors.forename: Dyanna
authors.initials: D
authors.lastname: Lambourn
authors.forename: Peter
authors.initials: P
authors.lastname: Olesiuk
authors.forename: Monique
authors.initials: M
authors.lastname: Lance
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Jeffries
authors.forename: Frank A P C
authors.initials: FA
authors.lastname: Gobas
authors.forename: Peter S
authors.initials: PS
authors.lastname: Ross
mesh_terms: D000818:Animals; D001955:British Columbia; D002170:Canada; D005260:Female; D005411:Flame Retardants / Q000494:pharmacology*; D055768:Halogenated Diphenyl Ethers / Q000494:pharmacology*; D008297:Male; D011078:Polychlorinated Biphenyls / Q000494:pharmacology*; D011157:Population Dynamics; D046070:Sea Lions / Q000502:physiology*; D014874:Water Pollutants, Chemical / Q000494:pharmacology*
chemical_list: D005411:Flame Retardants; D055768:Halogenated Diphenyl Ethers; D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls