Department of Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China.
Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental Resource Sciences, Zhejiang University, Hangzhou 310058, China.
Water Res. 2022 Jun 30;218:118466. doi: 10.1016/j.watres.2022.118466. Epub 2022 Apr 15.
Halobenzoquinones (HBQs) as disinfection byproducts (DBPs) in drinking water is prioritized for research due to their prevalent occurrence and high toxicity. However, only fifteen HBQs can be identified among a high diversity using targeted LC-MS/MS analysis in previous studies due to the lack of chemical standards. In this study, we developed a pseudo-targeted LC-MS/MS method for detecting and quantifying diverse HBQs. Distinct fragment characteristics of HBQs was observed according to the halogen substituent effects, and extended to the development of a multiple-reaction-monitoring (MRM) method for the quantification of the 46 HBQs that were observed in simulated drinking water using non-targeted analysis. The fragmentation mechanism was supported by the changes of Gibbs free energy (ΔG), and a linear relationship between the ΔG and the ionization efficiency of analytes was developed accordingly for quantification of these 46 HBQs, 30 of which were lack of chemical standards. It is noted that 29 of the 30 newly-identified HBQs were halo-methyl-benzoquinones (HMBQs), which were predicted to be carcinogens related with drinking-water bladder cancer risk and be more toxic than non-methyl HBQs. Using the new method, twelve HMBQs were detected in actual drinking water samples with concentrations up to 100.4 ng/L, 3 times higher than that reported previously. The cytotoxicity in CHO cells of HMBQs was over 1-fold higher than that of non-methyl-HBQs. Therefore, HMBQs are an essential, highly toxic group of HBQs in drinking water, which deserve particular monitoring and control.
卤代苯醌（HBQs）作为饮用水中的消毒副产物（DBPs），由于其普遍存在和高毒性而成为优先研究的对象。然而，在之前的研究中，由于缺乏化学标准品，仅使用靶向 LC-MS/MS 分析可以鉴定出 15 种 HBQs。在这项研究中，我们开发了一种用于检测和定量多种 HBQs 的伪靶向 LC-MS/MS 方法。根据卤素取代基效应观察到 HBQs 的独特片段特征，并将其扩展到使用非靶向分析对模拟饮用水中观察到的 46 种 HBQs 进行定量的多反应监测（MRM）方法的开发。该碎裂机制得到了吉布斯自由能（ΔG）变化的支持，并相应地建立了 ΔG 与分析物电离效率之间的线性关系，用于对这 46 种 HBQs 进行定量，其中 30 种缺乏化学标准品。值得注意的是，在 30 种新鉴定的 HBQs 中，有 29 种是卤代甲基苯醌（HMBQs），它们被预测为与饮用水膀胱癌风险相关的致癌物质，比非甲基 HBQs 毒性更大。使用新方法，在实际饮用水样品中检测到 12 种 HMBQs，浓度高达 100.4ng/L，比以前报道的浓度高 3 倍。HMBQs 在 CHO 细胞中的细胞毒性比非甲基-HBQs 高 1 倍以上。因此，HMBQs 是饮用水中必不可少的、高度毒性的 HBQs 组，值得特别监测和控制。
