School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, China; Resources and Environmental Innovation Institute, Shandong Jianzhu University, Jinan, 250101, China.
College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, 310058, China.
Chemosphere. 2021 Nov;283:131251. doi: 10.1016/j.chemosphere.2021.131251. Epub 2021 Jun 18.
Enoxacin (ENO) is widespread in water because it is commonly used as a human and veterinary antibiotic. However, little effort has been dedicated to revealing the transformation mechanisms of ENO destruction using ClO, especially within a water distribution system (WDS). To address this knowledge gap, the kinetics, byproducts, toxicity, and formation potential of halogenated disinfection byproducts (DBPs) associated with ENO destruction using ClO in a pilot-scale PE pipe was explored for the first time. Statistical analyses showed that the destruction efficiency of ENO in the pilot-scale PE pipe was lower than that in deionized water (DI water), and the reactions in DI water followed the second-order kinetic model. Furthermore, pH has a significant effect on the destruction of ENO, and the removal ratio increased at a higher pH. Additionally, increasing the flow rate elevated the ENO removal efficiency; however, the influence of flow velocity was limited to ENO destruction. The ENO removal rates within the diverse pipes exhibited the following order: stainless steel pipe < PE pipe < ductile iron pipe. Nine possible intermediates were identified, and those that were formed by piperazine group cleavage represented the major primary byproducts of the entire destruction process. Additionally, the ENO destruction in a pilot-scale PE pipe had minimal influence on halogenated DBPs and chlorite formation. Finally, the toxicity evaluation illustrated that the presence of ENO increased the potential risk of water quality safety when treated with ClO.
依诺沙星（ENO）作为一种常用的人用和兽用抗生素，在水中广泛存在。然而，人们很少致力于揭示 ClO 对 ENO 破坏的转化机制，尤其是在供水管网系统（WDS）中。为了填补这一知识空白，首次在中试规模的 PE 管中探索了使用 ClO 破坏 ENO 时的动力学、副产物、毒性和卤代消毒副产物（DBP）的形成潜力。统计分析表明，PE 管中 ENO 的破坏效率低于去离子水（DI 水），且 DI 水中的反应遵循二级动力学模型。此外，pH 值对 ENO 的破坏有显著影响，在较高 pH 值下去除率增加。此外，增加流速会提高 ENO 的去除效率；然而，流速的影响仅限于 ENO 的破坏。不同管道内的 ENO 去除率表现出以下顺序：不锈钢管<PE 管<球墨铸铁管。鉴定出了 9 种可能的中间产物，其中哌嗪基裂解形成的中间产物是整个破坏过程中的主要初级副产物。此外，PE 管中的 ENO 破坏对卤代 DBP 和亚氯酸盐的形成影响很小。最后，毒性评估表明，当用 ClO 处理时，ENO 的存在增加了水质安全的潜在风险。
