Laboratory of Environmental Pollution and Integrative Omics, Guilin Medical University, Guilin, PR China; Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China; State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong SAR, China.
Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China.
Chemosphere. 2022 Aug;301:134692. doi: 10.1016/j.chemosphere.2022.134692. Epub 2022 Apr 30.
Microplastic pollution, a pressing global environmental problem, has a severe impact on both aquatic ecosystems and public health worldwide. Due to the small size of microplastics, they are able to pass through the filtration systems of municipal wastewater treatment works (WWTWs). In recent years, studies have focused on the environmental abundance and ecotoxicological effects of microplastics, but there are limited studies investigating the colonization of microplastics by bacteria, especially those pathogenic ones. In this study, we examined the colonization and composition of the bacterial communities on polyethylene microbeads after incubation in raw sewage collected from three municipal WWTWs in Hong Kong (Sha Tin Sewage Treatment Works, Stonecutters Island Sewage Treatment Works, and Shek Wu Hui Sewage Treatment Works). Scanning electron microscopy (SEM) results indicate that bacterial cells were colonized on the surfaces of the microbeads and formed biofilms after sewage incubation. Metagenomic sequencing data demonstrated an increase in bacterial diversity after 21 days of sewage incubation when compared to shorter incubation periods of 6, 11 and 16 days. Importantly, human and fish pathogens such as Arcobacter cryaerophilus, Aeromonas salmonicida, Vibrio areninigrae and Vibrio navarrensis were found in the resident bacterial communities. Taken together, our results demonstrate that microplastics could act as a carrier for wastewater-borne pathogenic bacteria in municipal sewage.
微塑料污染是一个紧迫的全球性环境问题，对全球水生态系统和公众健康都有严重影响。由于微塑料的体积小，它们能够通过城市污水处理厂（WWTWs）的过滤系统。近年来，研究集中在微塑料的环境丰度和生态毒理学效应上，但对微塑料被细菌（尤其是那些致病性细菌）定殖的研究有限。在这项研究中，我们研究了在香港三个城市污水处理厂（沙田污水处理厂、石澳污水处理厂和石门污水处理厂）采集的原污水中培养后的聚乙烯微珠上细菌的定殖和群落组成。扫描电子显微镜（SEM）结果表明，细菌细胞在微珠表面定殖，并在污水培养后形成生物膜。与 6、11 和 16 天的较短培养时间相比，21 天污水培养后细菌多样性增加。重要的是，在定殖细菌群落中发现了人类和鱼类病原体，如嗜冷气单胞菌、鲑鱼气单胞菌、areninigrae 弧菌和 navarrensis 弧菌。总之，我们的结果表明，微塑料可以作为城市污水中污水传播的致病性细菌的载体。
