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目的 研究城市污水中环境雌激素(environmental estrogens,EEs)的去除情况,并评价其对受纳河流的影响.方法 分别采集郑州某污水处理厂进水口、初沉池、二沉池、出水口及受纳河流上、下游1 000 m(以下简称“河上游、河下游”)的水样,采用固相萃取-气质联用检测污水厂内水样雌酮(E1)、17β-雌二醇(E2)、4-辛基酚(OP)、4-壬基酚(NP)、双酚A(BPA)5种EEs的浓度.利用固相萃取/重组基因酵母法测定各采样点E2当量值(estradiol equivalents,EEQs).各采样点水样按照5％和10％的体积分数配制暴露溶液,并设空白对照(除氯自来水);将210尾雄性锦鲤采用半静态方式暴露,每组15尾,每天更换1/2暴露溶液,连续暴露7d.检测其血清卵黄蛋白原(vitellogenin,Vtg)并计算性腺成熟系数(gonadosomatic index,GSI).结果 所采水样均检测出EEs并诱导了雄性锦鲤血清Vtg的表达,并抑制其性腺的发育.出水口水样中雌激素活性均低于进水口和初沉池水样,差异有统计学意义(P＜0.05).河下游水样中雌激素活性高于河上游水样,差异有统计学意义(P＜0.05).各暴露组雄性锦鲤血清Vtg的浓度均高于对照组,差异有统计学意义(P＜0.05).在5％污水暴露组中,进水口和初沉池水样暴露雄性锦鲤血清Vtg的浓度间,差异无统计学意义(D0.05);二沉池水样暴露雄性锦鲤血清Vtg浓度低于进水口、初沉池水样,差异均有统计学意义(P＜0.05).在10％污水暴露组中,二沉池水样暴露雄性锦鲤血清Vtg的浓度高于进水口、初沉池水样,差异均有统计学意义(P＜0.05).相同浓度下游河水暴露雄性锦鲤血清的Vtg浓度均高于上游水样,差异均有统计学意义(P＜0.05).5％污水暴露组与10％组暴露组雄性锦鲤的GSI均低于对照组,差异有统计学意义(P＜0.05).在5％和10％污水暴露组中,二沉池水样暴露雄性锦鲤的GSI高于进水口、初沉池水样,差异均有统计学意义(P＜0.05);初沉池组和进水口水样暴露雄性锦鲤的GSI间比较,差异无统计学意义(P＞0.05);相同浓度下游河水暴露雄性锦鲤的GSI低于上游水样,差异均有统计学意义(P＜0.05).结论 污水厂二级生物处理对EEs的去除起主导作用,尾水的排放增加了河流中鱼类雌性化的风险,具有潜在的环境与健康风险.“,”Objective To explore the removal effect of environmental estrogens(EEs) in the wastewater in the different processes of the municipal wastewater treatment plant and to evaluate its impact on the receiving river.Methods The water samples were collected from the intake,primary sedimentation tank,secondary sedimentation tank and the outlet of one municipal wastewater treatment plant in Zhengzhou and within 1 000 meters of the downstream and upstream of Zhengzhou Qili River.The concentrations of five EEs (E2,E1,NP,OP,BPA) were detected by GC/MS methods and the estradiol equivalents of 17β-estradiol were detected by Recombinant Gene Yeast method.Experimental solutions were prepared as 5％(V/V) and 10％(V/V)using water samples from each sampling point and the dechlorination water was taken as the blank solution;A total of 210 male brocarded carps were randomly divided into 14 groups with 15 animals in each group and were semi-static exposed to the exposure solutions for seven consecutive days,during which half of the experimental solutions should be changed daily.The serum vitellogenin (Vtg) and gonadosomatic index (GSI) of the animals were detected.Results EEs were detected in all water samples and they had induced the expression of serum Vtg of the male animals while inhibited the development of their gonads organs.EEs activity in the outlet group was significantly lower than that of the intake group and the primary sedimentation tank group respectively (P＜0.05).EEs activity in the downstream group was significantly higher than that of the upstream group (P＜0.05).Serum Vtg concentration of the male animals in each exposure group was significantly higher than that of the control group (P＜0.05).In the 5％(V/V) exposure group,serum Vtg concentration of the male animals between the intake group and the primary sedimentation tank group had no significant difference (P＞0.05),but they were all significantly higher than that of the secondary sedimentation tank group (P＜0.05).While in the 10％(V/V) exposure group,serum Vtg concentration of the maleanimals in the intake group and the primary sedimentation tank group were both significantly lower than that of the secondary sedimentation tank group (P＜0.05).At the same exposure concentration,serum Vtg concentration of the male animals in the downstream group was significantly higher than that of the upstream group (P＜0.05).Besides,the GSI of the 5％(V/V) exposure group and the 10％(V/V) exposure group were both significantly lower than that of the control group (P＜0.05).In the 5％(V/V)exposure group and the 10％ (V/V) exposure group,the GSI of the secondary sedimentation tank group was significantly higher than that of the intake group and that of the primary sedimentation tank group (P＜0.05),while the GSI between the intake group and the primary sedimentation tank group had no statistically significant difference (P＞0.05).Besides,at the same exposure concentration,the GSI of male animals in the downstream group was significantly lower than that of the upstream group (P＜0.05).Conclusion The secondary biological treatment may play a leading role in the elimination of EEs.The discharge of tailrace increases the risk of feminization of fish in the polluted river and also has potential risk to environment and heakth.