污水处理厂中典型内分泌干扰物的去除效果研究

Remove of Typical Endocrine Disrupting Chemicals in Wastewater Treatment Plants

内分泌干扰物(Endocrine Disruption Chemicals,EDCs)在水中极低浓度下即会引起水生生物生殖发育、神经和免疫系统的异常,对人群的健康危害不容忽视。EDCs在污水厂中具有低浓度、难去除的特点,为进一步阐明污水处理厂不同处理工艺对此类EDCs的去除效果,采用化学分析法(气质联用法)和生物学方法(H295R和MVLN细胞实验法)分析东莞市2个城市污水处理厂中8种典型EDCs的分布特征和去除效果。结果显示,两污水厂进水中壬基酚(Nonlyphenol,NP)、辛基酚(Octylphenol,OP)、双酚A(Bisphenol A,BPA)浓度较高,NP质量浓度分别高达10 782 ng·L^(-1)和2 664 ng·L^(-1),而雌激素类物质雌酮(Estrone,E1)、雌二醇(17β-Estradiol,E2)与雌三醇(Estriol,E3)、17α-乙炔基雌二醇(17α-Ethinglestradiol,EE2)、己烯雌酚(Diethylstilbestrol,DES)浓度较低,经处理后,去除效率均超过90%。两污水厂进水及出水处理后H295R细胞内雌二醇(E2)水平显著升高,睾酮(Testosterone,T)水平呈下降趋势,类固醇合成基因HMGR、CYP11B2和CYP19表达量显著增加。MVLN细胞试验结果显示,两污水厂出水中雌激素当量(Estradiol Equivalency quotient,EEQ)分别达19.25ng·L^(-1)和14.21 ng·L^(-1)。本研究表明,即使化学分析结果显示EDCs去除率高达90%,且出水中雌激素化合物低于检出限,但是出水中类固醇激素干扰活性及雌激素活性依然存在。类固醇激素水平与水中酚类物质浓度没有显著相关性,A、B两个污水厂出厂水中除酚类化合物外,其他产生雌激素效应的化合物或类固醇合成干扰物也不容忽视。

Endocrine Disruption Chemicals(EDCs)in the water could cause reproductive,neural and immune toxicity to aquatic organism at low level,its’adverse health effects to human beings could not be ignored.The concentration of EDCs in the wastewater treatment plants(WWTPs)is pretty low,and hard to remove.To find a better way to evaluate the removal rate of EDCs by different treatment process,in this study,concentration of eight typical EDCs in two domestic WWTPs of Dongguan City was measured by GC/MS,and the endocrine disrupting effects including steroidogenesis disrupting effects and estrogenic activities were evaluated by H295R and MVLN cell bioassay,respectively.The results showed that the concentration of Nonylphenol(NP),Octylphenol(OP)and Bisphenol A(BPA)was very high in the influents,the mass concentration of NP in two WWTPs was up to 10 782 ng·L-1 and 2 664 ng·L-1,respectively.While,the concentration of estrogen compounds including Estrone(E1),17β-Estradiol(E2),Estriol(E3),17α-Ethinglestradiol(EE2)and Diethylstilbestrol(DES)in the influent of these two WWTPs was comparatively low.After treatment,the removal rate of EDCs was up to 90%.The E2 level was significantly increased after treating with the influent and effluent of both WWTPs,and the testosterone(T)level showed a decreasing trend,gene expression of steroidogenesis genes including HMGR,CYP11B2 and CYP19 were significantly up-regulated after the treatment of effluent.The effluent of the two WWTPs still showed a certain estrogenic activity,which the EEQ value was 14.21 ng·L-1 and 19.25 ng·L-1,respectively.In all,our study found although the chemical analysis showed that the removal rate of the typical EDCs was up to 90%,as well as the estrogen compounds were below the limit of detection in the effluent water,the steroidogenic disrupting effects and estrogenic activities still remained.There was no correlation between the concentration of BPA,OP,NP and the concentration of E2,except phenol compounds,other ER binding compounds,or compounds that disrupted steroidogenesis pathway should not be ignored in these two WWTPs.