Hao Tianwei, Miao Manhong, Wang Tong, Xiao Yihang, Yu Bingqing, Zhang Min, Ning Xiaoyu, Li Yao
Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau, China.
College of Environmental Science and Engineering/Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria/Tianjin Key Laboratory of Environmental Remediation and Pollution Control, Nankai University, Tong Yan Road 38, Tianjin, 300350, China.
Chemosphere. 2023 Jun;327:138488. doi: 10.1016/j.chemosphere.2023.138488. Epub 2023 Mar 22.
Microplastics (MPs) are substances that pose a risk to both human life and the environment. Their types and production are increasing year on year, and their potential to cause environmental pollution is a worldwide concern. Conventional water treatment processes, particularly coagulation and sedimentation, are not effective at removing all MPs. It is therefore important to assess the morphological changes in the MPs, i.e., the thermoplastic polyurethane (TPU) and polyethylene (PE), during ozonation and the dissolved organic carbon leaching as well as chloroform formation in the subsequent chlorination. The results show that the appearance and surface chemistry of the MPs changed during the ozonation process, most notably for TPU. The trichloromethane (CHCl) generation during chlorination was 0.168 and 0.152 μmol/L for TPU and PE, respectively, and the ozone pretreatment significantly increased the CHCl yield of TPU, while it had a weak effect on PE. Additional disinfection byproducts (DBPs), including CHClBr, CHClBr, and CHBr, were produced in the presence of bromide ions in the water column, and the total amount of DBPs produced by PE, PE-O, TPU, and TPU-O was significantly increased to 0.787, 0.814, 0.931, and 1.391 μmol/L, respectively. The study provides useful information for the environmental risk assessment of two representative MPs, i.e., TPU and MPs, in disinfection procedures for drinking water.
微塑料（MPs）是对人类生命和环境都构成风险的物质。它们的种类和产量逐年增加，其造成环境污染的可能性是全球关注的问题。传统的水处理工艺，特别是混凝和沉淀，在去除所有微塑料方面效果不佳。因此，评估微塑料（即热塑性聚氨酯（TPU）和聚乙烯（PE））在臭氧化过程中的形态变化以及随后氯化过程中溶解有机碳的浸出和氯仿的形成非常重要。结果表明，在臭氧化过程中微塑料的外观和表面化学性质发生了变化，TPU的变化最为明显。氯化过程中TPU和PE的三氯甲烷（CHCl）生成量分别为0.168和0.152 μmol/L，臭氧预处理显著提高了TPU的CHCl产率，而对PE的影响较弱。在水柱中存在溴离子的情况下会产生额外的消毒副产物（DBPs），包括CHClBr、CHClBr和CHBr，PE、PE-O、TPU和TPU-O产生的DBPs总量分别显著增加到0.787、0.814、0.931和1.391 μmol/L。该研究为饮用水消毒程序中两种代表性微塑料（即TPU和MPs）的环境风险评估提供了有用信息。
