长江(南京段)环境雌激素的污染特征

Characters of environmental estrogen pollution in Yangtze River (Nanjing section)

利用固相萃取技术和重组基因酵母检测了长江(南京段)四个典型断面环境雌激素污染状况。结果表明,除秦淮新河断面外,江心洲断面、三汊河断面和大桥断面均有环境雌激素的检出,雌二醇当量分别为0.38、0.24和0.45ng·L-1。与国内外地表水环境雌激素检测结果相比,长江(南京段)典型断面雌激素活性水平为较低至中等。对江心洲断面和大桥断面,甲醇洗脱组分的雌激素活性最大,其次为丙酮洗脱组分,二氯甲烷洗脱组分的雌激素活性最小;对三汊河断面,丙酮洗脱组分的雌激素活性最大,其次为二氯甲烷洗脱组分,甲醇洗脱组分的雌激素活性最小。这可能是污水来源不同所致,生活污水导致大量极性雌激素污染物的输入,而工业污水则主要引入了中等至弱极性雌激素污染物。三个雌激素活性阳性检出断面主要活性洗脱组分的雌激素活性均大于混合样的雌激素活性,这可能是由于样品混合后各种结构上不同的污染物之间的交互作用掩盖了实际的雌激素活性。

The estrogenic activities of the water samples collected from four representative sections of Yangtze River （Nanjing section） were determined using solid phase extraction followed by Yeast Estrogen Screen （YES） assay. The results showed that the water samples collected from Jiangxinzhou section,Sanchahe section and Daqiao section except for Qinhuaixinhe section exhibited positive results in YES assay and the estradiol equivalent （EEQ） was 0.38,0.24 and 0.45 ng·L^-1,respectively. Compared with the results in surface waters from domestic and foreign countries,the estrogenic activities in the four representative sections of Yangtze Rriver （Nanjing section） were at lower to moderate levels. For Jiangxinzhou section and Daqiao section,estrogenic activities were the most in the methanol fractions,followed by the acetone fractions and estrogenic activities were the least in the dichloromethane fractions. For Sanchahe section,estrogenic activity was the most in the acetone fraction,followed by the dichloromethane fraction and estro-genic activity was the least in the methanol fraction. Different source of wastewater may be responsible for the difference. It seemed that domestic wastewater brought more polar estrogens and industrial wastewater brought more moderate to low polar estrogens. The estrogenic activity of individual extracted fraction was higher than that of the mixed fraction in the above three sections. It was because interactions among structurally different estrogenic substances could mask the real estrogenic activity.