Application of a food web bioaccumulation model for the prediction of polychlorinated biphenyl, dioxin, and furan congener concentrations in Lake Ontario aquatic biota

A previously developed benthic/pelagic food web bioaccumulation model was p arameterized to predict concentrations of nine nonmetabolized polychlorinat ed biphenyl (PCB) congeners in invertebrates and fish from Lake Ontario. Pr edicted concentrations were compared with field-measured concentrations to verify the predictability of the model. Overall, 86% of model predictions w ere within a factor of 2 and 100% of predictions were within a factor of 10 of field-measured concentrations. The parameterized model was used to esti mate chemical metabolic rates for 15 PCB, polychlorinated dibenzo-p-dioxin (PCDD), and polychlorinated dibenzo-p-furan (PCDF) congeners that are poten tially metabolized. Estimated chemical metabolic rates ranged from 7.5 x 10 (-3) to 1.0 x 10(-7).day(-1) and were in general agreement with qualitative studies describing rates of metabolism of these chemicals by aquatic biota . The calibrated model was used to predict concentrations of all 24 PCB, PC DD, and PCDF congeners in invertebrates and fish commonly found in Lake Ont ario but for which no field-measured data exist. These concentrations were expressed as the logarithm of the bioaccumulation factor (log BAF). The log BAF's in benthic invertebrates and salmonids ranged from 4.2 to 10.2 and f rom 5.1 to 11.6, respectively, and were consistent with field-measured BAF' s.