State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China; School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China; School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
J Environ Sci (China). 2016 Apr;42:61-70. doi: 10.1016/j.jes.2015.05.020. Epub 2015 Aug 4.
Based on the fact that recycling of combined filter backwash water (CFBW) directly to drinking water treatment plants (WTP) is considered to be a feasible method to enhance pollutant removal efficiency, we were motivated to evaluate the genotoxicity of water samples from two pilot-scale drinking water treatment systems, one with recycling of combined backwash water, the other one with a conventional process. An integrated approach of the comet and micronucleus (MN) assays was used with zebrafish (Danio rerio) to investigate the water genotoxicity in this study. The total organic carbon (TOC), dissolved organic carbon (DOC), and trihalomethane formation potential (THMFP), of the recycling process were lower than that of the conventional process. All the results showed that there was no statistically significant difference (P>0.05) between the conventional and recycling processes, and indicated that the genotoxicity of water samples from the recycling process did not accumulate in 15 day continuous recycling trial. It was worth noting that there was correlation between the concentrations of TOC, DOC, UV254, and THMFPs in water and the DNA damage score, with corresponding R(2) values of 0.68, 0.63, 0.28, and 0.64. Nevertheless, both DNA strand breaks and MN frequency of all water samples after disinfection were higher than that of water samples from the two treatment units, which meant that the disinfection by-products (DBPs) formed by disinfection could increase the DNA damage. Both the comet and MN tests suggest that the recycling process did not increase the genotoxicity risk, compared to the traditional process.
基于将组合滤池反冲洗水（CFBW）直接回收至饮用水处理厂（WTP）被认为是提高污染物去除效率的一种可行方法这一事实，我们有动机评估来自两个中试规模饮用水处理系统的水样的遗传毒性，一个是回收组合反冲洗水的系统，另一个是常规处理系统。本研究采用彗星和微核（MN）试验的综合方法，用斑马鱼（Danio rerio）来研究水的遗传毒性。回收过程的总有机碳（TOC）、溶解有机碳（DOC）和三卤甲烷生成潜能（THMFP）均低于常规过程。所有结果均表明，常规工艺与回收工艺之间无统计学差异（P＞0.05），表明在 15 天连续回收试验中，回收工艺水样的遗传毒性并未累积。值得注意的是，TOC、DOC、UV254 和 THMFPs 浓度与 DNA 损伤评分之间存在相关性，相应的 R（2）值分别为 0.68、0.63、0.28 和 0.64。然而，所有水样经消毒后的 DNA 链断裂和 MN 频率均高于两个处理单元水样，这意味着消毒形成的消毒副产物（DBPs）会增加 DNA 损伤。彗星和 MN 试验均表明，与传统工艺相比，回收工艺并未增加遗传毒性风险。
