Exposure to Perfluoroalkyl Substances and Polybrominated Diphenyl Ethers from Traditionally Harvested Food Animals on St. Lawrence Island, Alaska

Abstract

The Arctic serves as a hemispheric sink for persistent organic pollutants(POPs). Indigenous arctic populations are exposed to POPs through traditional harvest of food animals, including marine mammals. This study quantified 13 perfluoroalkyl substances (PFAS) and 40 polybrominated diphenyl ethers in traditional food animals harvested by residents of St. Lawrence Island, Alaska. Of 13 measured PFAS, 9 were detectable in any sample. Overall PFAS concentrations were highest in seal tissue. In seal tissue samples, Perfluoropentanoic acid (PFPeA) was the most commonly detected PFAS, and was present at the highest mean concentration of any PFAS (15.4 ng/g ww). PFPeA was also the most commonly detected PFAS and was present the highest maximum concentration (24.8 ng/g in seal muscle). Analysis of heart, liver, kidney and intestine samples from a single juvenile seal suggest that PFAS may preferentially partition into organs. Both total concentrations of PFAS and the number of detectable compounds were higher in these organ meats. Polybrominated diphenyl ethers (PBDEs) were detected in 100% of traditional foods samples. BDE-47, 99, 100 and 209 tended to make up a large percentage of overall PBDE concentrations. Seals had the highest median concentrations compared to other species. BDE-47 made up the majority of overall PBDE concentrations in seal samples. The median total PBDE concentration in seal blubber from this study (2,511 pg/g ww) was lower than the concentration reported in harbor seals collected in Alaska in 2000-2002 (14,600 pg/g ww). This is consistent with the overall decreasing trends of PBDEs in the Arctic.