Perfluorinated alkyl substances in plasma, liver, brain, and eggs of glaucous gulls (Larus hyperboreus) from the Norwegian Arctic

Recent environmental surveys have ascertained the widespread occurrence of perfluorinated alkyl substances (PFAS) in tissues of wildlife from the Arctic. In the present study, we investigated the distribution of a suite of PFAS in plasma, liver, brain, and egg samples from adult glaucous gulls (Larus hyperboreus), an apex scavenger-predator seabird breeding in the Norwegian Arctic. Perfluorooctane sulfonate (PFOS) was the predominant PFAS in all samples and was present at concentrations that are the highest reported thus far in any arctic seabird species and populations. Among the body compartment/ tissue samples analyzed, PFOS was highest in plasma (48.1-349 ng/g wet weight (ww)), followed by liver approximate to egg > brain. Perfluorocarboxylic acids (PFCAs) with 8-15 carbon (C) atoms were found, with the highest concentrations determined in plasma (sum PFCA: 41.8-262 ng/g ww), whereas 5C- and 6C-PFCAs were below the limits of detection. Perfluorobutane sulfonate, perfluorooctane sulfonamide, and four saturated (8:2 FTCA and 10:2 FTCA) and unsaturated (8:2 FTUCA and 10:2 FTUCA) fluorotelomer carboxylic acids were not detected in any samples. Perfluorohexane sulfonate was measured at concentrations up to 2.71 ng/g ww. The accumulation profiles of PFCAs were characterized by high proportions of the long and odd-numbered carbon-chain-length compounds, namely perfluoroundecanoic (11C) and perfluorotridecanoic acid (13C), although their individual contribution differed between the matrixes analyzed. Current PFAS concentrations suggest a bioaccumulation potential in Norwegian arctic glaucous gulls that needs to be assessed as part of a broad organohalogen contaminant cocktail with potential for mediating biological processes in this vulnerable top-predator marine species.