饮用水新型卤代醌消毒副产物的形成机制及毒性效应研究

Disinfection byproducts (DBPs), formed from the reaction between disinfectants and organic matter, are potentially correlated with an increased risk of bladder cancer. Haloquinones are a class of emerging DBPs of potential carcinogenic relevance, with toxicity much higher than that of regulated DBPs, but the formation and toxicity of haloquinones are unclear. This project aims at state-of-the-art scientific issues of the identification and regulation of the health risk of DBPs, focuses on the formation mechanism and toxicity effects of haloquinones. Combing laboratory experiment and field study, the project aims to elucidate the relationship between the occurrence and concentration of haloquinone DBPs and the organic composition of source waters, reveal the natural and anthropogenic precursors and sources of haloquinone DBPs, clarify the influence of drinking water treatments on the formation of haloquinone DBPs, and discuss the formation mechanism and control methods; characterize the bladder cytotoxicity of haloquinones, elucidate the influence of chemical structures, i.e. types, positions and numbers of functional groups, on the toxicity of haloquinones, study the metabolism pathways and products of haloquinones, reveal the effects and molecular mechanism of haloquinones on endogenous metabolism, in order to understand the health risk and control principle of haloquinone DBPs. In summary, the result of the proposed project is expected to provide scientific basis for the health risk assessment and control of DBPs, regulatory consideration for the quality of drinking water, and the production of safe drinking water.

氯化消毒副产物(DBPs)健康风险控制是当前饮用水安全亟需解决的重要问题。最新发现卤代醌类新型DBPs致膀胱癌的风险远高于常见的DBPs，但其形成过程及致毒机理尚不清楚。本项目拟针对DBPs的健康风险识别及调控等前沿科学问题，以卤代醌DBPs的形成机制及毒性效应为研究核心，拟采用实验模拟和现场试验相结合的方法，研究饮用水卤代醌的生成(种类与浓度)与水源有机物组成的关系，探明卤代醌的天然、人为前体物及来源；探明饮用水处理工艺对卤代醌生成的影响，探讨卤代醌形成的机制及调控原理；表征卤代醌的膀胱细胞毒性效应，阐明卤代醌分子结构，特别是官能团类型、位置及数量对毒性的影响；研究卤代醌的代谢通路及转化产物，探讨卤代醌对内源代谢的影响及分子机制，从而阐明卤代醌的健康风险及控制技术原理，为评价及控制DBPs健康风险、制定相关水质卫生标准、保障饮用水安全提供科学依据。

本项目围绕饮用水中卤代醌类新型消毒副产物的形成机制及毒性效应展开，建立质子反向迁移-液质联用分析方法，解决卤代醌不稳定、难电离、信号弱的分析难题，构建卤代醌靶向及拟靶向液质联用谱检测方法，在饮用水中定量检出60种卤苯醌、羟基卤苯醌、卤苯醌氯亚胺、卤代萘醌新型消毒副产物；建立了基于高分辨质谱特征碎片及衍生化分子标记的卤苯醌前驱物逐级识别溯源技术，揭示生物高分子及木质素中的芳香性羟基及羧基结构是生成卤苯醌的活性结构单元；建立拟靶向及中性丢失卤苯醌代谢产物质谱分析方法，阐明卤苯醌通过与谷胱甘肽发生氧化还原循环、取代、加成等反应的抗氧化机制，揭示二酮结构和卤素取代基是DNA加合位点，证实卤代醌类消毒副产物的毒性比受控消毒副产物高上千倍。发表SCI论文6篇（2篇ES&T，1篇Water Res，1篇CREST，1篇Chem Eng J），申请发明专利1项。