Environmental Simulation and Pollution Control State Key Joint Laboratory, School of Environment, Tsinghua University , Beijing, P.R. China.
Environ Sci Technol. 2014 Oct 21;48(20):12362-9. doi: 10.1021/es503621e. Epub 2014 Oct 7.
Disinfectants inactivate pathogens in source water; however, they also react with organic matter and bromide/iodide to form disinfection byproducts (DBPs). Although only a few DBP classes have been systematically analyzed for toxicity, iodinated and brominated DBPs tend to be the most toxic. The objectives of this research were (1) to determine if monochloramine (NH2Cl) disinfection generated drinking water with less toxicity than water disinfected with free chlorine (HOCl) and (2) to determine the impact of added bromide and iodide in conjunction with HOCl or NH2Cl disinfection on mammalian cell cytotoxicity and genomic DNA damage induction. Water disinfected with chlorine was less cytotoxic but more genotoxic than water disinfected with chloramine. For both disinfectants, the addition of Br(-) and I(-) increased cytotoxicity and genotoxicity with a greater response observed with NH2Cl disinfection. Both cytotoxicity and genotoxicity were highly correlated with TOBr and TOI. However, toxicity was weakly and inversely correlated with TOCl. Thus, the forcing agents for cytotoxicity and genotoxicity were the generation of brominated and iodinated DBPs rather than the formation of chlorinated DBPs. Disinfection practices need careful consideration especially when using source waters containing elevated bromide and iodide.
消毒剂可在原水中消灭病原体；但它们也会与有机物和溴化物/碘化物反应，形成消毒副产物（DBPs）。尽管只有少数几类 DBPs 被系统地分析过毒性，但碘代和溴代 DBPs 往往毒性最大。本研究的目的是：(1) 确定使用一氯胺 (NH2Cl) 消毒是否会生成比使用自由氯 (HOCl) 消毒毒性更小的饮用水；(2) 确定与 HOCl 或 NH2Cl 消毒结合添加溴化物和碘化物对哺乳动物细胞细胞毒性和基因组 DNA 损伤诱导的影响。用氯消毒的水比用氯胺消毒的水细胞毒性更小，但遗传毒性更大。对于这两种消毒剂，Br(-) 和 I(-) 的添加都会增加细胞毒性和遗传毒性，而 NH2Cl 消毒的反应更大。细胞毒性和遗传毒性都与 TOBr 和 TOI 高度相关。但是，毒性与 TOCl 呈弱负相关。因此，导致细胞毒性和遗传毒性的原因是溴代和碘代 DBPs 的生成，而不是氯化 DBPs 的形成。消毒实践需要仔细考虑，特别是在使用含有高溴化物和碘化物的水源时。
