Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Department of Environmental Resources Research, National Institute of Environmental Research, Hwangyong-ro 42, Seogu, Incheon 22689, Republic of Korea.
Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Shenzhen Laboratory of Microorganism Application and Risk Control, Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen, Shenzhen 518055, PR China.
Sci Total Environ. 2021 Mar 25;762:144161. doi: 10.1016/j.scitotenv.2020.144161. Epub 2020 Dec 17.
Reverse osmosis concentrate (ROC) resulting from treatment of municipal wastewater reclamation involves high concentrations of recalcitrant pollutants. This study evaluated the toxicity of an ROC containing harmful biocides during representative UV synergistic oxidation processes (SOPs) (e.g., UV/hydrogen peroxide (HO), UV/persulfate (PS), and UV/PS/Cu). Treated ROC exhibited up to 1.3-2.3 times higher toxicity than the parent compounds such as dodecyl trimethyl ammonium chloride (DTAC) and dodecyl dimethyl benzyl ammonium chloride (DDBAC). Based on the intermediates identification, the major toxic intermediates were screened through silico assessment using the quantitative Ecological Structure-Activity Relationship (ECOSAR) tool. The transformation products (TPs) of hydroxylation and ketonization were the major formed reactions from the UV/PS/Cu. Also, some cytotoxic TPs were accumulated during the UV/HO and UV/PS oxidations, where the carbonaceous-disinfection byproducts were more than the nitrogenous-disinfection byproducts. In the presence of chloride and bromide, chlorate and bromate could be formed during the UV-SOP; they were influenced by the different water matrix in comparison with the different ROC. Also, the formation of the total organic halogen species (TOX) was found to follow this order: UV/PS/Cu < UV/HO < UV/PS. In this study, the predicted cytotoxicity using the correlation between the TOX and the cytotoxicity was more acceptable than that of the cytotoxicity index method. Further, the R-square of the correlation between the TOX and the cytotoxicity for the UV/HO and UV/PS was 0.82 and 0.79, respectively. The predicted cytotoxicity using the TOX correlation method in the ROC could also be used to monitor and prevent the application of different oxidations in municipal wastewater reclamation treatment plants.
反渗透浓缩液（ROC）是处理城市污水再生过程中产生的，其中含有高浓度的难降解污染物。本研究评估了含有有害杀生剂的 ROC 在代表性紫外线协同氧化过程（SOP）（例如 UV/过氧化氢（HO）、UV/过硫酸盐（PS）和 UV/PS/Cu）中的毒性。处理后的 ROC 表现出比母体化合物（如十二烷基三甲基氯化铵（DTAC）和十二烷基二甲基苄基氯化铵（DDBAC））高 1.3-2.3 倍的毒性。基于中间产物的鉴定，通过使用定量生态结构-活性关系（ECOSAR）工具的计算评估筛选出主要的有毒中间产物。UV/PS/Cu 主要发生羟化和酮化反应。此外，在 UV/HO 和 UV/PS 氧化过程中会积累一些细胞毒性 TPs，其中碳质消毒副产物比氮质消毒副产物多。在有氯和溴存在的情况下，UV-SOP 过程中会形成氯酸盐和溴酸盐；与不同的 ROC 相比，它们受不同水基质的影响。此外，总有机卤素（TOX）的形成被发现遵循以下顺序：UV/PS/Cu<UV/HO<UV/PS。在本研究中，通过 TOX 与细胞毒性之间的相关性预测细胞毒性比细胞毒性指数法更具可接受性。此外，UV/HO 和 UV/PS 之间 TOX 与细胞毒性的相关性的 R 方分别为 0.82 和 0.79。在城市污水再生处理厂中，使用 TOX 相关性方法预测 ROC 的细胞毒性也可用于监测和防止不同氧化作用的应用。
