近年有关药物及其转化产物的环境污染问题引起了人们的广泛关注。其中苯二氮卓类药物是一类作用于中枢神经系统的药物，其母体化合物和代谢产物均具有镇静、催眠及抗焦虑等作用。苯二氮卓类药物及其代谢产物大多随污水进入污水处理厂，但其污水处理过程中的环境归趋及消减机制研究十分薄弱。本项目拟选择三座不同工艺类型的珠三角城市生活污水处理厂为研究对象，基于污水的流行病学研究方法和质量平衡估算研究常见苯二氮卓类药物及其代谢产物在污水处理过程中的分布特征和去除规律；采用高分辨质谱技术和理论化学计算相结合研究典型苯二氮卓类药物的活性污泥法（微生物）转化产物、消毒处理工艺（氯化、紫外）的消毒副产物，评估其毒性变化规律；实验室对比研究高级氧化处理技术（臭氧氧化技术、光氯联用技术、高铁处理技术等）对污水中残留的苯二氮卓类药物及其转化产物的消减机制。研究成果为有效消除水环境中苯二氮卓类药物的污染问题提供科学依据。

In recent years pharmaceuticals and their transformation products have received increasing attentions in general public and scientific community due to their environmental contamination issue. Benzodiazepines are a class of psychiatric pharmaceuticals which can affect mammalian central nervous system functions. Benzodiazepines and their metabolites have sedative, muscle relaxant, anxiolytic, anticonvulsive and antiepileptic properties. After use, these compounds enter into the wastewater treatment plants (WWTPs) via discharge of domestic wastewaters, but little is known about their occurrence and fate in WWTPs. This project aims to investigate the concentration levels and removal efficiencies of common benzodiazepines and their metabolites in municipal WWTPs in the Pearl River Delta Region based on the wastewater-based epidemiology and mass balance analysis. Through high resolution mass spectrometry and theoretical calculation, this project will study the transformation products of selected benzodiazepines by activated sludge treatment process, chlorination and UV disinfection and their toxicity evaluation. This project will also comparative study the removal of selected benzodiazepines and their transformation products in WWTPs effluents by advanced oxidation processes such as ozonation, UV/Chlorine, Solar/Chlorine and ferrate treatment technology. This project will provide the scientific basis for mitigation of benzodiazepine pharmaceuticals in aquatic environments.