| Summary: | Although bioaccumulation of polychlorinated biphenyls (PCBs) in food webs is well-recognized, this phenomenon is not currently incorporated into the methodology for developing sediment quality guidelines (SQGs) in British Columbia. The aim of this study is to develop and apply an empirical and modelling approach to the development of sediment quality criteria for the protection of marine mammals, using harbour seal pups as a proxy. An average empirical Biota-Sediment Accumulation Factor (BSAF) of 490 (lower SD 220, upper SD 1100) g-dry-weight sediment/ g-lipid-weight biota (n=6) was calculated for ΣPCBs, which was overestimated by the model predication (BSAF of 1000 g-dry-weight sediment/ g-lipid-weight biota). Using the empirical BSAF and a Threshold Effects Concentration (TEC) of 1.3 μg PCB/g lipid, a SQG for ΣPCBs of 0.82 ng/g dw is proposed in order to protect 95% of the pup seal population, which is not being achieved by the current SQG of 20 ng/g dw.
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