Microplastics and microorganisms in sediments from stormwater drain system

Yudong Chen; Siping Niu; Jianghua Yu; Jing Wu; Tiantian Wang

doi:10.1016/j.scitotenv.2023.164284

Microplastics and microorganisms in sediments from stormwater drain system

Sci Total Environ. 2023 Sep 1:889:164284. doi: 10.1016/j.scitotenv.2023.164284. Epub 2023 May 16.

Authors

Yudong Chen¹, Siping Niu², Jianghua Yu³, Jing Wu¹, Tiantian Wang¹

Affiliations

¹ Department of Environmental Science and Engineering, School of Energy and Environment, Anhui University of Technology, Ma'anshan, People's Republic of China.
² Department of Environmental Science and Engineering, School of Energy and Environment, Anhui University of Technology, Ma'anshan, People's Republic of China. Electronic address: sipingniu@126.com.
³ Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), Nanjing University of Information Science & Technology, Nanjing 210044, People's Republic of China.

PMID: 37201807
DOI: 10.1016/j.scitotenv.2023.164284

Abstract

Research has already confirmed the occurrence of microplastics (MPs) in sediments of stormwater drain system (SDS). However, the microplastic pollution remains to be elucidated well in sediments, especially the spatio-temporal distribution and the impacts of MPs on microorganisms. In this study, the averaged abundance of MPs in SDS sediments was 479 ± 688 items·kg^-1 for spring, 257 ± 93 items·kg^-1 for summer, 306 ± 227 items·kg^-1 for autumn and 652 ± 413 items·kg^-1 for winter. As expected, the abundance of MPs was the lowest in summer due to runoff scouring, while the highest in winter attributed to infrequent low-intensity rainfall. The major polymers of MPs were polyethylene terephthalate and polypropylene plastics, occupying 76 % to 98 % of the total number. Fiber MPs were the most regardless of season (41 % to 58 %). MPs with size of 250-1000 μm accounted for over 50 %, which is in accordance with the previous study that MPs of <1000 μm were the major. High-throughput sequencing of analysis shows that MPs provided an ecological niche for bacterial communities different from that of SDS sediments. Actinomycetes and bacteria with chemoheterotrophic genes tended to be enriched on the surfaces of MPs. In addition, Acidobacteria and bacteria with nitrification genes would not like to present in microplastisphere. A strong positive correlation (R from 0.74 to 0.83, P < 0.01) was found between the abundance of MPs in sediments and the abundance of functional genes for denitrification and nitrogen respiration of microorganisms on the surfaces of MPs. It indicates that MPs may influence the nitrogen transformation processes in SDS sediments via the occurrence of denitrification processes on the surfaces of MPs. The abundance of MPs had no significant relationship with the various functional genes of microorganisms in the sediments (P > 0.05), which means that MPs could not profoundly influence the expression of microbial functional genes in SDS sediments.

Keywords: Microorganisms; Microplastics; Nitrogen cycle; Sediments; Stormwater drain system.

MeSH terms

Environmental Monitoring
Geologic Sediments
Microplastics*
Plastics
Water Pollutants, Chemical* / analysis

Substances

Microplastics
Plastics
Water Pollutants, Chemical