Poster presented at SETAC Europe 21st Annual Meeting, Milano, Italia, 15-19 mai 2011.
PP 08/2011 (pdf)
Summary: Short chain chlorinated paraffins (SCCPs), also called polychlorinated n-alkanes, are mixtures of compounds of molecular formula CxH2x+2-yCly containing 10-13 carbon atoms and usually 30-70 % degree of chlorination. They have a range of industrial applications, and have been detected in numerous environmental compartments. There is concern regarding SCCPs due to their environmental persistence and their potential for bioaccumulation, adverse effects and long-range transport. SCCPs have been included in the UNECE LRTAP Convention, the priority substance list of the European Water Framework Directive, and are under consideration for the Stockholm Convention on Persistent Organic Pollutants. However, the behaviour and fate of SCCPs remain poorly understood, in part as the technical mixtures consist of thousands of isomers, enantiomers and diastereomers, which make analysis and modelling of these compounds very challenging. The purpose of this study was to explore a complementary modelling and monitoring approach to evaluate the overall understanding of the link between emissions of SCCPs, environmental levels and human exposure in the Nordic environment and to identify the more critical knowledge gaps. Data for emissions and physicochemical properties of SCCPs were gathered or estimated, and used to parameterize an integrated, non-steady state environmental fate and bioaccumulation model (CoZMoMan). Specific congeners of SCCPs were selected for the study to assess the extent of expected variation of environmental fate and behaviour within the multitude of compounds. Model results were next compared to reported environmental levels in the Nordic region. For compartments where environmental levels were scarce or lacking, targeted sampling and analysis was carried out to further evaluate the model predictions. Results from this study will be presented and discussed with emphasis on the more critical research needs with respect to the overall fate and exposure of SCCPs.