Estrogenic activity in coastal areas around Japan evaluated by measuring male serum vitellogenins in Japanese common goby Acanthogobius flavimanus

抄録

Surveys of the estrogenic activity in coastal areas of Japan were performed by using two serum vitellogenins (Vg-530 and Vg-320) of male Japanese common goby Acanthogobius flavimanus as biomarkers. To evaluate the relationship between the Vg concentrations in the serum of male fish and the concentrations of environmental estrogens in seawater, 3 week exposure experiments were performed using estradiol (E₂), nonylphenol (NP) and bisphenol A (BPA). From the results of the E₂ exposure, mean concentrations of the Vg and the ratio of Vg-positive fish increased from actual concentration at 10.5 ng/L E₂ treatment. Exposure of NP and BPA showed that the 19.0 μg/L NP treatment induced the Vg but 133.7 μg/L BPA did not. As for the survey of the estrogenic activity in coastal areas, the mean Vg concentrations and ratio of Vg-positive fish in some urban areas were similar to values of the 10.5 ng/L E₂ treatment. Although E₂ and NP were detected in the seawater from urban areas, the concentrations were concluded as not sufficient to independently induce the Vg. Considering these results, it is concluded that the total estrogenic activity in some urban areas is dependent not only on E₂ but synergistically with other environmental estrogens.