Center for Applied Geoscience, Eberhard Karls Universität Tübingen, D-72074 Tübingen, Germany.
Int J Environ Res Public Health. 2018 Feb 7;15(2):287. doi: 10.3390/ijerph15020287.
Microplastic particles in terrestrial and aquatic ecosystems are currently discussed as an emerging persistent organic pollutant and as acting as a vector for hydrophobic chemicals. Microplastic particles may ultimately deposit and accumulate in soil as well as marine and freshwater sediments where they can be harmful to organisms. In this study, we tested the sensitivity of natural freshwater sediment bacterial communities (by genetic fingerprint) to exposure to microplastics (polyethylene, 2 and 20 mg/g sediment) and microplastics loaded with polycyclic aromatic hydrocarbons (PAHs, phenanthrene and anthracene), using a laboratory-based approach. After two weeks of incubation, the bacterial community composition from an unpolluted river section was altered by high concentrations of microplastics, whereas the community downstream of a wastewater treatment plant remained unchanged. Low microplastic concentrations loaded with phenanthrene or anthracene induced a less pronounced response in the sediment communities compared to the same total amount of phenanthrene or anthracene alone. In addition, biodegradation of the PAHs was reduced. This study shows, that microplastic can affect bacterial community composition in unpolluted freshwater sediments. Moreover, the results indicate that microplastics can serve as a vehicle for hydrophobic pollutants but bioavailability of the latter is reduced by the sorption to microplastics.
陆地和水生生态系统中的微塑料颗粒目前被认为是一种新兴的持久性有机污染物，并充当疏水性化学物质的载体。微塑料颗粒最终可能会沉积和积累在土壤以及海洋和淡水中的沉积物中，从而对生物造成危害。在这项研究中，我们使用基于实验室的方法，测试了天然淡水沉积物细菌群落（通过遗传指纹）对暴露于微塑料（聚乙烯，2 和 20mg/g 沉积物）和负载多环芳烃（菲和蒽）的微塑料的敏感性。经过两周的孵育，高浓度的微塑料改变了未受污染的河流段的细菌群落组成，而污水处理厂下游的群落则保持不变。与单独的相同总量的菲或蒽相比，低浓度的负载有菲或蒽的微塑料对沉积物群落的诱导作用较小。此外，多环芳烃的生物降解减少了。本研究表明，微塑料可以影响未受污染的淡水沉积物中的细菌群落组成。此外，结果表明，微塑料可以作为疏水性污染物的载体，但后者的生物利用度由于与微塑料的吸附而降低。
