Centre for Infectious Disease Control (CIb), National Institute for Public Health and the Environment (RIVM), Bilthoven, Netherlandss; Institute for Risk Assessment Sciences (IRAS), Utrecht University, Utrecht, Netherlands.
Centre for Infectious Disease Control (CIb), National Institute for Public Health and the Environment (RIVM), Bilthoven, Netherlandss.
Water Res. 2021 Mar 15;192:116852. doi: 10.1016/j.watres.2021.116852. Epub 2021 Jan 19.
Plastic pollution in aquatic environments, particularly microplastics (<5 mm), is an emerging health threat. The buoyancy, hydrophobic hard surfaces, novel polymer carbon sources and long-distance transport make microplastics a unique substrate for biofilms, potentially harbouring pathogens and enabling antimicrobial resistance (AMR) gene exchange. Microplastic concentrations, their polymer types and the associated microbial communities were determined in paired, contemporaneous samples from the Dutch portion of the river Rhine. Microplastics were collected through a cascade of 500/100/10 μm sieves; filtrates and surface water were also analysed. Microplastics were characterized with infrared spectroscopy. Microbial communities and selected virulence and AMR genes were determined with 16S rRNA-sequencing and qPCR. Average microplastic concentration was 213,147 particles/m; polyamide and polyvinylchloride were the most abundant polymers. Microbial composition on 100-500 μm samples differed significantly from surface water and 10-100 μm or smaller samples, with lower microbial diversity compared to surface water. An increasingly 'water-like' microbial community was observed as particles became smaller. Associations amongst specific microbial taxa, polymer types and particle sizes, as well as seasonal and methodological effects, were also observed. Known biofilm-forming and plastic-degrading taxa (e.g. Pseudomonas) and taxa harbouring potential pathogens (Pseudomonas, Acinetobacter, Arcobacter) were enriched in certain sample types, and other risk-conferring signatures like the sul1 and erm(B) AMR genes were almost ubiquitous. Results were generally compatible with the existence of taxon-selecting mechanisms and reduced microbial diversity in the biofilms of plastic substrates, varying over seasons, polymer types and particle sizes. This study provided updated field data and insights on microplastic pollution in a major riverine environment.
水生环境中的塑料污染，特别是微塑料（<5mm），是一个新出现的健康威胁。由于其具有浮力、疏水性硬质表面、新型聚合物碳源和远距离传输的特性，微塑料成为生物膜的独特基质，可能携带病原体，并使抗生素耐药（AMR）基因发生交换。本研究在荷兰境内莱茵河的同期配对样本中，测定了微塑料的浓度、其聚合物类型和相关微生物群落。通过 500/100/10μm 的筛网对微塑料进行收集；还分析了滤出物和地表水。利用红外光谱对微塑料进行了表征。采用 16S rRNA 测序和 qPCR 确定了微生物群落和选定的毒力和 AMR 基因。平均微塑料浓度为 213147 个/粒子；聚酰胺和聚氯乙烯是最丰富的聚合物。100-500μm 样本上的微生物组成与地表水以及 10-100μm 或更小的样本有显著差异，与地表水相比，微生物多样性较低。随着颗粒变小，观察到微生物群落越来越“水样化”。还观察到特定微生物类群、聚合物类型和颗粒大小之间的关联，以及季节性和方法学效应。在某些样本类型中，发现了已知的生物膜形成和塑料降解类群（如假单胞菌）和携带潜在病原体的类群（如假单胞菌、不动杆菌、弯曲杆菌），而其他具有风险的特征，如 sul1 和 erm(B) AMR 基因几乎普遍存在。结果通常与生物膜中塑料基质的选类机制和微生物多样性减少有关，这种变化在季节、聚合物类型和颗粒大小上有所不同。本研究提供了在主要河流环境中微塑料污染的最新现场数据和见解。
