Gao Xiaoting, Wang Xianshi, Jiang Youwei, Kong Dezhen, Pan Xiangrui, Ma Jun, Liu Yanan
College of Environmental Science and Engineering, Donghua University, 2999 North Renmin Road, Shanghai 201620, China.
State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
J Hazard Mater. 2024 Jan 5;461:132692. doi: 10.1016/j.jhazmat.2023.132692. Epub 2023 Oct 2.
Halogenated benzoquinones (HBQs) are frequently detected in tap water. HBQ levels are correlated with water age. As the water-transmission distance (water age) increases, the levels of bromo-benzoquinones (Br-BQs) decreased and those of chloro-benzoquinones (Cl-BQs) remained relatively stable in drinking water-distribution system in the presence of residual chlorine. 2,3,5,6-Tetrachloro-1,4-benzoquinone (TCBQ) and 2,6-dibromo-1,4-benzoquinone (DBBQ) were the most abundant Cl-BQ and Br-BQ, with maximum concentrations of 60.2 and 181.4 ng/L, respectively. TCBQ and DBBQ were chosen as representatives of HBQs to investigate their reactions with chlorine, including kinetics, pathways, and changes in toxicity. The hydrolysis and chlorination rates of HBQs were significantly pH-dependent, and the kinetic rates of DBBQ were faster than TCBQ in the pH range of 5-10. Chlorination converted highly toxic TCBQ and DBBQ to less-toxic chlorinated/brominated aliphatic disinfection by-products (DBPs), thereby reducing the overall toxicity of water bodies. This study provides comprehensive insights into the distinct life cycles of TCBQ and DBBQ in drinking water, covering formation, transformation, and toxicity. These findings provide a nuanced understanding of the risks posed by HBQs at various locations within the drinking water distribution system, offering valuable guidance for improving the control of DBPs in drinking water.
卤代苯醌（HBQs）在自来水中经常被检测到。HBQ水平与水龄相关。在存在余氯的饮用水分配系统中，随着输水距离（水龄）增加，溴苯醌（Br-BQs）水平下降，而氯苯醌（Cl-BQs）水平保持相对稳定。2,3,5,6-四氯-1,4-苯醌（TCBQ）和2,6-二溴-1,4-苯醌（DBBQ）分别是含量最高的Cl-BQ和Br-BQ，最大浓度分别为60.2和181.4 ng/L。选择TCBQ和DBBQ作为HBQs的代表，研究它们与氯的反应，包括动力学、反应途径和毒性变化。HBQs的水解和氯化速率显著依赖于pH值，在5-10的pH范围内，DBBQ的动力学速率比TCBQ快。氯化作用将高毒性的TCBQ和DBBQ转化为毒性较低的氯化/溴化脂肪族消毒副产物（DBPs），从而降低水体的整体毒性。本研究全面深入地了解了饮用水中TCBQ和DBBQ独特的生命周期，涵盖了形成、转化和毒性方面。这些发现为细致理解饮用水分配系统中不同位置的HBQs所带来的风险提供了依据，并为改进饮用水中DBPs的控制提供了有价值的指导。
