饮用水中消毒副产物与其前驱体的非靶向分析识别技术及生成机制研究

Drinking water disinfection is regarded as a significant advance of public health in the 20th century. However, during disinfection processes, disinfection by-products are formed and also a threat to human health. Although more than 600 disinfection by-products have been reported, there are still a large number of unknown organic halides produced by disinfection. Based on our previous work, this project will develop a non-target analysis method for disinfection by-products. In order to detect and identify disinfection by-products with complex structures, parameters of sample preparation and instrument will be optimized, and data processing technology will be developed. With the non-target analysis method, distribution of disinfection by-products (including transformation products of pollutants) under different disinfectants will be investigated, and disinfection reaction pathways of natrual organic matter and pollutants will also be identified. Finally, we will investigate the occurrence of dissolved organic matter and disinfection by-products in the whole the production chain of drinking water and identify the potential precursor for disinfection by-products, and then the formation mechanism of disinfection by-products will be confirmed by laboratory experiment. This project will broaden the scope of disinfection by-products, and provide theoretical basis for the pollution control of disinfection by-products.

饮用水消毒被认为是20世纪人类公共卫生发展的重大进步，但消毒导致的消毒副产物也威胁着人群健康。尽管有600多种消毒副产物已经被发现，但仍有大量消毒产生的有机卤化物未被人类所认知。本研究将在前期工作基础上，构建消毒副产物高通量非靶向分析识别方法，优化前处理技术与仪器分析参数，开发数据识别技术；探究不同工艺流程下消毒副产物与消毒转化产物的分布规律，解析饮用水中天然有机质与污染物消毒转化反应途径；探究水厂饮用水生产链中溶解有机质与消毒副产物的转化规律，识别导致消毒副产物产生的潜在前驱有机质，通过实验室消毒实验探究消毒副产物产生机制，从而完善消毒副产物清单，并为消毒副产物的污染控制提供理论依据。

本项目围绕大量消毒副产物未被解析的科学问题，聚焦消毒副产物识别与结构解析的技术瓶颈：开展了从样品前处理到数据分析全过程的消毒副产物非靶向分析技术体系研究工作，优化了基于亲水-亲酯平衡聚合物、阴离子交换聚合物、阳离子交换聚合物三种类型固相萃取小柱串联的高覆盖度有机物提取方法，并针对高分辨率质谱采集的冗余质谱大数据，自主开发了涵盖氟、氯、溴、碘四种典型卤素元素化合物非靶向识别策略集与基于统计分析策略的消毒副产物及前体物的非靶向识别策略；进而利用该技术开展饮用水中氯代、溴代消毒副产物调查，发现了600余种潜在氯代、溴代消毒副产物，并鉴定出卤代酚、卤乙酸、卤代水杨酸、卤代水杨醛等19种传统消毒副产物，以及硝基酚、磺酸类、羟基环戊烯二酮、咪唑和氨基酸为母体的五类共18种新型氯代、溴代消毒副产物；进一步采用非靶向分析技术，评估了饮用水厂不同工艺单元对微量有机物的去除与转化过程，结果表明无论预处理、沉淀过滤还是消毒工艺，都伴随着大量转化产物的生成，消毒工艺是转化产物产生的主要来源，并在消毒工艺出水中检出2-羟基西玛津、3,5-二溴-4-羟基苯甲酸、2-磺酸基苯并噻唑3种转化产物，暗示人工合成化学品也是消毒副产物重要前体物；最后通过实验室模拟消毒动力学试验探究消毒副产物的生成机制，可吸附有机卤化物与消毒副产物及前体物非靶向分析的结果，都表明消毒过程存在快速反应、缓慢反应与稳定三个阶段，但从非靶向特征峰的趋势分析看，消毒过程，甚至在稳定阶段，化学物质结构发生快速的变化，消毒副产物生成过程是一个动态复杂的过程，不同消毒时间的消毒副产物种类与含量存在明显差异。通过本项目研究为消毒副产物的识别与分析提供了新的技术手段，拓宽了消毒副产物以及其生成机制的认知，加速了后续消毒副产物阻控技术的研究。