Target and semi-quantitative non-target analysis of per- and polyfluoroalkyl substances (PFAS) in Arctic animals

Per- and polyfluoroalkyl substances (PFAS) are pervasive environmental contaminants due to their persistence, bioaccumulation potential and adverse effects. This study applied target and non-target screening analysis in an exploratory approach to the identification of emerging PFAS in Arctic animals, including polar bears, ringed seals, glaucous gulls, ptarmigans and shorthorn sculpins. Target analysis detected 21 PFAS, with the highest ∑PFAS in a polar bear sample (3238 ng/g wet weight). Perfluorooctane sulfonate (PFOS) was still the dominant PFAS except for shorthorn sculpin, where perfluoropentane sulfonate (PFPeS) prevailed. Several replacement PFAS (including perfluoro-4-ethylcyclohexane sulfonate (PFECHS), chlorinated polyfluoroalkylether sulfonates (Cl-PFESA) and 4,8-dioxa-3H-perfluorononanoic acid (ADONA)) and the precursor perfluorooctane sulfonamide (PFOSA) were also detected, with highest concentrations in polar bears. Non-target screening identified 16 emerging PFAS, with polar bears showing the greatest diversity (13 compounds), followed by ringed seals (4) and glaucous gulls (4) while no additional emerging PFAS were identified in ptarmigan and shorthorn sculpin. Among these PFAS, 2H,2H,3H,3H-perfluorodecanoic acid (7:3 fluorotelomercarboxylic acid; FTCA) and perfluorooctylphosphonic acid (PFOPA) were detected across multiple species. A semi-quantification approach indicated that emerging PFAS may contribute substantially to the overall PFAS burden in polar bear, ringed seal and glaucous gull samples, highlighting the importance of expanding PFAS monitoring and risk assessments to emerging PFAS in Arctic ecosystems.