Occurrence, bioaccumulation and trophodynamics of per- and polyfluoroalkyl substances (PFAS) in terrestrial and marine ecosystems of Svalbard, Arctic

Per- and polyfluoroalkyl substances (PFAS) enter the Arctic through long-range transport and local pollution. To date, little is known about their behavior in plant and benthic marine food webs in remote Arctic. In this study, we analyzed the environmental distribution and nutrient transfer of 20 PFAS in soil, sediment, plant and benthic biota samples collected between 2014 and 2016 in Svalbard, Arctic. Total concentrations of PFAS were in the ranges of 0.12-4.84 ng/g dry weight (dw) in soil, 0.15-0.93 ng/g dw in sediment, 0.11-16.6 ng/g dw in plant, and 0.049-26.2 ng/g dw in marine biota. Perfluorocarboxylic acids (PFCAs) dominated Σ₂₀PFAS in all sample types except amphipods, in which perfluorooctane sulfonate (PFOS) made up 80 % of Σ₂₀PFAS. The profile of PFAS components observed in the terrestrial and marine ecosystems suggests that atmospheric transport and oxidation of volatile precursors are important sources of PFCAs in the Arctic region. However, the impact of long-distance ocean transport and local emissions cannot be ignored. The biota-sediment or biota-soil bioaccumulation factors (BSAF) differed among plants and biota species, with mountain avens (BSAF of Σ₂₀PFAS: 12.1) and amphipods (BSAF of Σ₂₀PFAS: 44.9) having higher accumulation potential. PFOS, perfluorohexane sulfonamide (FHxSA) and Σ₂₀PFAS have biomagnification potential in Arctic benthic biota, but short-chain PFCA exhibits trophic dilution. This is one of few studies to investigate the environmental behavior of PFAS in terrestrial and aquatic ecosystems in the remote Arctic, providing a basis for investigating the ecological risks of PFAS in polar regions.