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(W/EH103) Bioaccumulation of Phthalate Esters in Aquatic Food-Chains: Models vs. Data. Webster, Glenys1, Mackintosh, Cheryl1, Jing, Hongwu2, Ikonomou, Michael2, Gobas, Frank1, 1 2 ABSTRACT- Dialkyl phthalate esters (DPEs) are widely used as non-reactive plasticizers in vinyl plastics and in a broad range of industrial and consumer products. A wide range of DPE congeners can be found at the ppm level in sediments in the US and Western Europe. Because of their hydrophobic nature (log Kows range between 1.61 and 12.06), PEs are expected to be "bioaccumulative" substances with the potential to accumulate in aquatic food-chains. However, field and laboratory bioaccumulation data, which mainly exist for DEHP but which are rare for other DPEs, indicate that the bioaccumulation behavior of DPEs may be less than expected from log Kow. This study presents an overview of the laboratory and field bioaccumulation data for DPEs. The overview includes previously published data as well as the results from a recently completed marine food-chain bioaccumulation field study of a series of DPEs, including dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), butyl benzyl phthalate (BBP), di(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP). A fugacity-based analysis of the data is presented and the bioaccumulation behavior of DPEs is shown to deviate from established bioaccumulation paradigms. Hypotheses and a bioaccumulation model are presented to explain the bioaccumulation behavior of DPEs. Key words: Bioaccumulation, Phthalate esters, Aquatic, Food-chain |
