Distribution of endocrine-disrupting PCBs in hard roes of loaches and their potential ecological effects in Weishanhu Lake, China.

Preliminary study is carried out on the endocrine-disrupting organic chemicals of polychlorinated biphenyls( PCBs: PCB-28, 60, 104, 153, 190) in hard roes of loaches( Misgurnus anguillicaudatas) in Weishanhu Lake, China. Results showed that the hard roes of loaches collected from the areas near the influx(such as Pengkou T-PCB = 0.243 microg/g) or efflux(such as Hanzhuang T-PCB = 0.221 microg/g) are characterized by higher PCB contents, about 4 times that from the central lake(T-PCB = 0.066 microg/g), suggesting great difference between their pollutions. The PCB distributions indicated that PCB congeners with more chlorine are more easily accumulated in roes of loaches. The microscopic characteristics reveal that the PCB contents at present cannot lead the roes of loaches to be abnormal. However, the roes with higher PCBs in Pengkou and Hanzhuang are obviously bigger than those with lower PCBs(T-PCBs < or = 0.176 microg/g) in other localities. It is suggested that PCBs have a stronger estrogenic activity on the roes of loaches, and the phenomenon is likely premonitory for the abnormal development of the hard roes.