Center for Water Cycle Research, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea; Faculty of Environment and Labour Safety, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
Center for Water Cycle Research, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea; Division of Energy & Environment Technology, KIST School, Korea University of Science and Technology (UST), Seoul 02792, Republic of Korea.
J Hazard Mater. 2024 Aug 5;474:134751. doi: 10.1016/j.jhazmat.2024.134751. Epub 2024 May 28.
Chlorination on microplastic (MP) biofilms was comprehensively investigated with respect to disinfection efficiency, morphology, and core microbiome. The experiments were performed under various conditions: i) MP particles; polypropylene (PP) and polystyrene (PS), ii) MP biofilms; Escherichia coli for single-species and river water microorganisms for multiple-species, iii) different chlorine concentrations, and iv) different chlorine exposure periods. As a result, chlorination effectively inactivated the MP biofilm microorganisms. The disinfection efficiency increased with increasing the free chlorination concentration and exposure periods for both single- and multiple-species MP biofilms. The multiple-species MP biofilms were inactivated 1.3-6.0 times less than single-species MP biofilms. In addition, the PP-MP biofilms were more vulnerable to chlorination than the PS-MP biofilms. Morphology analysis verified that chlorination detached most MP biofilms, while a small part still remained. Interestingly, chlorination strongly changed the biofilm microbiome on MPs; the relative abundance of some microbes increased after the chlorination, suggesting they could be regarded as chlorine-resistant bacteria. Some potential pathogens were also remained on the MP particles after the chlorination. Notably, chlorination was effective in inactivating the MP biofilms. Further research should be performed to evaluate the impacts of residual MP biofilms on the environment.
本研究全面考察了微塑料（MP）生物膜的氯化作用，涉及消毒效率、形态和核心微生物组。实验在以下各种条件下进行：i）MP 颗粒；聚丙烯（PP）和聚苯乙烯（PS），ii）MP 生物膜；大肠杆菌单种生物膜和河水微生物多种生物膜，iii）不同的氯浓度，和 iv）不同的氯暴露时间。结果表明，氯化作用有效地灭活了 MP 生物膜微生物。对于单种和多种 MP 生物膜，消毒效率随自由氯化浓度和暴露时间的增加而增加。与单种 MP 生物膜相比，多种 MP 生物膜的灭活效率低 1.3-6.0 倍。此外，PP-MP 生物膜比 PS-MP 生物膜更容易受到氯化作用的影响。形态分析验证了氯化作用会使大多数 MP 生物膜脱落，而一小部分仍留在 MP 上。有趣的是，氯化作用强烈改变了 MPs 上的生物膜微生物组；一些微生物的相对丰度在氯化后增加，表明它们可以被视为抗氯细菌。一些潜在的病原体也在氯化后残留在 MP 颗粒上。值得注意的是，氯化作用在灭活 MP 生物膜方面非常有效。应进一步研究评估残留 MP 生物膜对环境的影响。
