Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing, 210098, PR China; College of Environment, Hohai University, Nanjing, 210098, PR China.
Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing, 210098, PR China; College of Environment, Hohai University, Nanjing, 210098, PR China.
Chemosphere. 2022 Sep;302:134892. doi: 10.1016/j.chemosphere.2022.134892. Epub 2022 May 7.
As an emerging persistent pollutant, microplastics (MPs) have been detected in the drinking water system and its potential risk in the presence of disinfectants has received little attention. This work aimed to investigate the changes in MPs properties and the organic matter leaching behavior of MPs during chlorination. Physical and chemical changes of the chlorinated MPs were detectable by scanning electron microscope, Micro-Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Polystyrene (PS) was less resistant to chlorination than polyethylene (PE), indicated by changes in Raman peaks and O/C ratio of the XPS spectrum. Organic matter leaching behavior of MPs was explored by dissolved organic carbon (DOC) determination and disinfection byproducts formation potential measurement. The results demonstrated the stimulating effect of chlorination on the organic matters leaching from MPs, with the total leached DOC accounting for ∼0.3‰-0.5‰ of the MPs mass. The leached organic matters exhibited an appreciable potential to form trihalomethanes (THMs) and haloacetonitriles (HANs). The formation potential of THMs and HANs were 54.43-185.08 μg/mg C and 3.65-11.83 μg/mg C, respectively. Compared to PE, organic matter leaching behavior during chlorination was more obvious for PS. This study provides insights into the fate of chlorinated microplastics and the possible risk of organic matters leached from MPs to form disinfection byproducts during chlorination.
作为一种新兴的持久性污染物，微塑料（MPs）已在饮用水系统中被检出，但其在存在消毒剂时的潜在风险却很少受到关注。本研究旨在考察 MPs 在氯化过程中性质的变化和 MPs 中有机物的浸出行为。扫描电子显微镜、微拉曼光谱和 X 射线光电子能谱（XPS）可检测到氯化 MPs 的物理和化学变化。通过拉曼峰的变化和 XPS 谱中 O/C 比的变化，表明聚苯乙烯（PS）比聚乙烯（PE）更不耐氯化。通过测定溶解有机碳（DOC）和消毒副产物生成潜能，探索了 MPs 中有机物的浸出行为。结果表明，氯化对 MPs 中有机物浸出具有刺激作用，总浸出的 DOC 占 MPs 质量的约 0.3‰-0.5‰。浸出的有机物形成三卤甲烷（THMs）和卤乙腈（HANs）的潜力较大。THMs 和 HANs 的生成潜能分别为 54.43-185.08 μg/mg C 和 3.65-11.83 μg/mg C。与 PE 相比，PS 中有机物在氯化过程中的浸出行为更为明显。本研究深入了解了氯化微塑料的归宿以及氯化过程中 MPs 中浸出有机物形成消毒副产物的可能风险。
