AROCLOR-1268 AND TOXAPHENE IN FISH FROM A SOUTHEASTERN US ESTUARY

PCBs and toxaphene were analyzed in fish and their prey from an indust rialized estuary in southeastern Georgia (USA). PCB concentrations wer e highest in forage fish (170 mu g/g lipid) and were 1-3 orders of mag nitude higher in biota from a heavily contaminated salt marsh in the u pper estuary as compared with levels in similar species from two refer ence sites. Tissue PCB profiles matched that of Aroclor 1268, a highly chlorinated formulation used exclusively at a Superfund site in the u pper estuary. Tissue profiles of fish gut contents and of species repr esenting a simple food chain indicated that PCBs are likely transferre d via the food web. Components of toxaphene, which was discharged from a facility in the lower estuary, were detected and confirmed in fatty organs of fish using gas chromatography with electron capture and mas s spectrometric detection. Estimated toxaphene concentrations were 0.5 -1 mu g/g lipid. These results suggest that PCBs and toxaphene from po int sources in different parts of the estuary are transferred locally through the food web and that fish transport these contaminants out of the heavily contaminated salt marshes during their semiannual movemen ts within the estuary.