Long-range Transport of Per- and Polyfluorinated Substances to Sweden : The Exposure in Mountain Grazing Reindeers

Abstract: The aim of this study was to examine if perfluorinated alkylated substances (PFASs) reaches north of Sweden by long-range atmospheric transport. This was done by monitoring the levels of PFASs in reindeer livers at two locations in 2002 and 2010, respectively. The reindeers have lived all of their lives in the mountains and therefore the main source of exposure for PFASs is through air. The samples were extracted and analysed for 24 different PFASs using ultra performance liquid chromatography tandem mass spectrometer (UPLC-MS/MS). The most significant change concerns perfluorooctane sulfonic acid (PFOS) which decreased significantly from 6.1 ng/g at the most northern location (Ammarnäs/Biergenis) in 2002 to 0.87 ng/g 2010. At the other sampling location, Glen, PFOS decreased from 5.0 to 3.2 ng/g during the eight years. Mainly PFOS and longer chain carboxylates were found. The results revealed that the levels of many compounds decreased in time. The location seems to have an impact on the level of perfluorinated compounds present and most likely the distribution of them in the air, since certain PFASs have increased and decreased differently in time between the two locations. Since PFASs are non-volatile, they are believed to be degradation products of volatile compounds such as fluorotelomer alcohols (FTOHs) and perfluoroalkylated sulfonamido alcohols (FOSEs). FTOHs and FOSEs are released, translocated by long-range atmospheric transport and degraded to perfluorinated compounds in organisms or atmosphere.