DISTRIBUTION OF POLYCHLORINATED-BIPHENYLS IN DAB (LIMANDA-LIMANDA) FROM THE BAIE-DE-SEINE (EASTERN CHANNEL)

Polychlorinated biphenyls (PCBs) were determined in liver, muscle and gonad tissues of dab from the Baie de Seine. Very similar PCB patterns were observed in all samples; the main components possess the -245, -234, -2345 chlorine substitution. Contamination levels varied with the lipid content of the tissues. The highest concentrations were found in liver in the range 100-700 ng g-1 dry weight for the PCB congener No. 153 (22'44'55' hexachlorobiphenyl). The concentrations in liver and muscle increased with age for both male and female fish. Gonads from male fish showed continued low contamination. However, the contamination in gonads from mature female fish (> 2 years) varied during the year: the highest concentrations were observed in early spring, just before the spawning which is an important pathway for the elimination of these contaminants.