Per- and Polyfluoroalkyl Substances (PFAS) in Sub-Antarctic Seabirds: Insights into Long-Range Transport and Bioaccumulation of Legacy and Replacement Chemicals

Per- and polyfluoroalkyl substances (PFAS) are widespread environmental pollutants that can bioaccumulate in biota and cause a variety of adverse effects. Seabirds are useful bioindicators of pollutants in marine food webs because they are apex predators with broadly known diets and distributions, and concentrations in their tissues therefore reflect background exposure in particular regions and ecosystems. Concentrations of PFAS are high in seabirds in the Northern Hemisphere, but there have been few studies in the Southern Hemisphere, particularly in the sub-Antarctic, and these mostly involved a limited target list of PFAS. We detected 22 PFAS, of a target list of 39 compounds, in three species of procellariform seabirds (albatrosses and petrels) with different diets and migration strategies, sampled in two areas in the southwest Atlantic Ocean in 2004-2014. PFAS concentrations are reported for the first time in common diving petrels and white-chinned petrels. Concentrations in liver tissue varied significantly among species and years, with ΣPFAS ranging over 2 orders of magnitude from 0.08 to 7.5 ng/g (ww). Despite this variation in total concentrations, chemical contamination profiles were broadly similar, comprising mainly perfluorooctanesulfonic acid (PFOS) (∼80%) and perfluoroalkyl carboxylic acids (PFCAs) (∼15%), suggesting PFAS fingerprints are much the same despite the contrasting diets, trophic levels and distributions. This signature closely reflects mixtures found in south Atlantic waters and provides evidence of long-range transport of atmospheric precursors. Emerging compounds of concern including hexafluoropropylene oxide dimer acid (HFPO-DA), dodeceafluoro-3H-,4,8-dioxanonoate (ADONA), and short-chain perfluoroalkyl acids (PFAAs) were detected in some samples. This study provides evidence of contamination in biota and highlights the value of biomonitoring of remote environments.