饮用水中碘乙酸的内分泌干扰效应及其生殖发育毒性研究

Iodoacetic acid is a kind of new unregulated disinfection byproducts in drinking water treatment process. Our previous studies indicated that the concentration of iodoacetic acid was very low in drinking water but its cytotoxicity, genotoxicity, and potential carcinogenicity were stronger than regulated bromo- and chloro- disinfection byproducts. In recent years, many studies showed that reproductive and developmental abnormalities were related to disinfection byproducts exposure. Endocrine disrupting effects of disinfection byproducts was considered as one of potential reasons. However, it is difficult to do the health risk assessment comprehensively because we still lack of knowing of endocrine disrupting effects and reproductive/developmental toxicity of iodoacetic acid until now. Owing to its strong toxicity and potential reproductive /developmental hazard, endocrine disrupting effects and reproductive/developmental toxicity of iodoacetic acid will be assessed on the base of establishing a battery of short term methods for determining estrogen, androgen, and thyroid hormone disrupting effects, reproductive/developmental toxicity screening test, and iodoacetic acid exposure level in people. And the molecular of action of endocrine disrupting effects will be clarified. Results of the study will lay the foundation for the screening and accessing endocrine disrupting chemical in drinking water. Meanwhile, it will provide the important scientific evidences for the revision of standard for drinking water quality.

碘乙酸是饮用水消毒过程中新发现的一类未受控消毒副产物，本项目组前期研究已表明碘乙酸在水中含量虽低，但其细胞毒性、遗传毒性和潜在致癌性均强于受控的溴系和氯系消毒副产物。近年来饮用水消毒副产物对生殖和发育异常的影响备受关注，消毒副产物具有内分泌干扰效应被认为是潜在影响因素之一。然而，目前针对碘乙酸的内分泌干扰效应及其生殖发育毒性仍缺乏了解，因此难以综合评价其健康风险。基于碘乙酸毒性大和对生殖和发育存在潜在危害，本研究拟在构建雌激素、雄激素和甲状腺激素干扰效应短期配套检测体系和生殖发育毒性筛选试验方法的基础上，结合人群实际暴露碘乙酸水平，研究碘乙酸的内分泌干扰效应和生殖发育毒性，并从基因和蛋白水平阐明其分子调控机制。研究结果将为饮用水内分泌干扰物的筛选和评估奠定基础，同时为饮用水水质卫生标准的修订提供重要的科学依据。

碘乙酸是饮用水消毒过程中新发现的一类未受控消毒副产物，本项目组前期研究已表明碘乙酸在水中含量虽低，但其细胞毒性、遗传毒性和潜在致癌性均强于受控的溴系和氯系消毒副产物。近年来饮用水消毒副产物对生殖和发育异常的影响备受关注，消毒副产物具有内分泌干扰效应被认为是潜在影响因素之一。然而，目前针对碘乙酸的内分泌干扰效应及其生殖发育毒性仍缺乏了解，因此难以综合评价其健康风险。基于碘乙酸毒性大和对生殖和发育存在潜在危害，本研究拟在构建雌激素、雄激素和甲状腺激素干扰效应短期配套检测体系和生殖发育毒性筛选试验方法的基础上，研究碘乙酸的内分泌干扰效应和生殖发育毒性，并从基因和蛋白水平阐明其分子调控机制。本研究结果显示，碘乙酸可能具有甲状腺激素和雄激素干扰效应，并具生殖发育毒性。碘乙酸可通过下调促甲状腺素、钠钾转动体和脱碘酶I而减少T3合成，并反馈性上调下丘脑重量，继而促进促甲状腺素释放激素和促甲状腺素合成增加。同时碘乙酸还可引起甲状腺小滤泡形成增多、坏死和空泡形成。本研究结果将为饮用水内分泌干扰物的筛选和评估奠定基础，同时为饮用水水质卫生标准的修订提供重要的科学依据。