Polychlorinated biphenyl accumulation differs among pumpkinseed sunfish during experimental field exposure: the role of invertebrate prey

The relative importance of aqueous vs. trophic exposure of fish to polychlo rinated biphenyls (PCBs) was investigated. The potential role of different invertebrate prey upon PCB accumulation by fish was also investigated. Pump kinseed sunfish (Lepomis gibbosus) were exposed in the upper Hudson River u nder conditions that either permitted feeding upon different local prey ass emblages, or excluded local prey from fish diets. Total [PCB] was 5 x great er in fish exposed to local prey versus those not permitted to feed on loca l prey. Further, fish with trophic exposure to PCBs exhibited a chlorine sh ift, a significantly higher proportion of more chlorinated isomers than fis h with only aqueous exposure. Total [PCB] differed among benthic invertebra te assemblages. Phytophilous invertebrates had lower [PCB] than benthic inv ertebrates, and also had lower concentrations of the more chlorinated isome rs. Short-term (7-day) exposure of fish did not permit differentiation of P CB accumulation in fish according to differences in diet of native prey ass emblages. (C) 2001 Elsevier Science B.V. All rights reserved.