Congener Specific PCB Concentrations in Fish from the Fox River, Wisconsin, USA, 1997 Environmental Conference Proceedings

The lower Fox River/Green Bay ecosystem (Wisconsin, USA) is highly industrialized and is contaminated from past discharges of polychlorinated biphenyls. As part of a cooperative study between local industries and the Wisconsin Department of Natural Resources, PCB concentrations in Fox River fish were determined by both Aroclor and congener specific methods. Congener specific analyses were conducted using a multidimensional gas chromatographic (MDGC) method in use at Fort Howard Corporation which can quantitate congeners that are difficult to measure by common congener specific methods. These congeners, referred to as coplanar PCBs due to their molecular structure, are of particular interest to some state and federal regulators as a result of their reportedly elevated toxicity. Ten fish samples from the lower river showed total PCB concentrations (the sum of individual congeners) between 1.09 and 7.05 mg/kg wet weight (ww). Good agreement was observed between Aroclor and congener specific methods. In general, higher proportions of coplanar congeners were observed in samples containing higher proportions of pentachlorobiphenyls. Concentrations of all coplanar congeners measured except congener 77 were significantly lower in the Fox River fish than in fish tissues from Lake Michigan and Lake Ontario reported in the literature.