Factors Affecting Fish Concentrations of PCBs

overall, the bioaccumulation of PCBs is a function of the uptake of PCBs from water and food, and the losses due to metabolism, excretion, and growth dilution all are a function of time. A general model for estimating the concentration of PCBs (Cflsh) in fish is  

The length of the food chain has the largest effect on the observed accumulation of PCBs in top predators [268]. However, one of the more sensitive aspects of trophic transfer in food webs is the initial uptake of PCBs into the primary trophic level, phytoplankton [263]. The BCF from water to phytoplankton is approximately 105 -106, and subsequent BMFs to higher trophic levels are on the order of two to five. Due to the life cycle of most phytoplankton, their rate of growth is on the same order as their rate of uptake of PCBs, thus making their uptake very time-dependent [227,269-271]. Bioaccumulation into top predators will be greater if phytoplankton have a chance 

PCBs have been documented to occur in nearly all trophic levels throughout the Great Lakes ecosystem [282], including bacteria (Hudson, unpub- 

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