Risk assessment of perfluorinated chemicals for the North Sea and Westerschelde
Recent studies have indicated that perfluorinated chemicals show high persistence and distribution in various wildlife species. These chemicals are commonly used as solvents, surfactants and are applied in fire foam extinguishers but also for stain and/or wet resistance of paper and textile. One compound, perfluoro-octane sulfonic acid (PFOS) has been detected in organisms living at remote, non-industrialized areas.The purpose of the present study is to investigate the levels of these perfluorinated chemicals and their potential effects. Preliminary studies indicate that levels up to 85ng/g can be found in fish caught in the Westerschelde estuary.The sampling campaigns aim at characterizing the accumulation potential through the different trophic levels. These data will be completed with effect laboratory-based studies in order to derive safe threshold levels. In previous studies we already characterized the effects of PFOS on aspects of the endocrine metabolism of wildlife species. Furthermore we were able to pinpoint toxicological mechanisms using cellular reporter assays.membrame damage, oxidative stress and associated DNA damage were the most important effects noted. Biochemical studies with freshwater fish showed liver-necrosis like effects after a short term exposure period.Based on these effects and exposure data we will perform a rsik assessment for these chemicals for the North Sea and Westerschelde estuary.