Effect of microplastics on microbial dechlorination of a polychlorinated biphenyl mixture (Aroclor 1260)

Xinkai Li; Qiang Xu; Youjun Cheng; Chunlei Chen; Chaofeng Shen; Chunfang Zhang; Daoqiong Zheng; Dongdong Zhang

doi:10.1016/j.scitotenv.2022.154904

Effect of microplastics on microbial dechlorination of a polychlorinated biphenyl mixture (Aroclor 1260)

Sci Total Environ. 2022 Jul 20:831:154904. doi: 10.1016/j.scitotenv.2022.154904. Epub 2022 Mar 29.

Authors

Xinkai Li¹, Qiang Xu², Youjun Cheng³, Chunlei Chen⁴, Chaofeng Shen⁵, Chunfang Zhang⁶, Daoqiong Zheng⁷, Dongdong Zhang⁸

Affiliations

¹ Institute of Marine Biology and Pharmacology, Ocean College, Zhejiang University, Zhoushan 316021, Zhejiang, China. Electronic address: lxk2019@zju.edu.cn.
² Ocean Academy, Zhejiang University, Zhoushan 316021, Zhejiang, China. Electronic address: 05clkxxq@zju.edu.cn.
³ Institute of Marine Biology and Pharmacology, Ocean College, Zhejiang University, Zhoushan 316021, Zhejiang, China. Electronic address: 3150100652@zju.edu.cn.
⁴ Institute of Marine Biology and Pharmacology, Ocean College, Zhejiang University, Zhoushan 316021, Zhejiang, China. Electronic address: 21834042@zju.edu.cn.
⁵ Department of Environmental Engineering, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, Zhejiang, China. Electronic address: ysxzt@zju.edu.cn.
⁶ Institute of Marine Biology and Pharmacology, Ocean College, Zhejiang University, Zhoushan 316021, Zhejiang, China. Electronic address: zhangcf@zju.edu.cn.
⁷ Institute of Marine Biology and Pharmacology, Ocean College, Zhejiang University, Zhoushan 316021, Zhejiang, China. Electronic address: zhengdaoqiong@zju.edu.cn.
⁸ Institute of Marine Biology and Pharmacology, Ocean College, Zhejiang University, Zhoushan 316021, Zhejiang, China. Electronic address: zhangdongzju@zju.edu.cn.

PMID: 35364163
DOI: 10.1016/j.scitotenv.2022.154904

Abstract

Microplastics (MPs) and polychlorinated biphenyls (PCBs) generally coexist in the environment, posing risks to public health and the environment. This study investigated the effect of different MPs on the microbial anaerobic reductive dechlorination of Aroclor 1260, a commercial PCB mixture. MP exposure inhibited microbial reductive dechlorination of PCBs, with inhibition rates of 39.43%, 23.97%, and 17.53% by polyethylene (PE), polypropylene (PP), and polystyrene (PS), respectively. The dechlorination rate decreased from 1.63 μM Cl^- d^-1 to 0.99-1.34 μM Cl^- d^-1 after MP amendment. Chlorine removal in the meta-position of PCBs was primarily inhibited by MPs, with no changes in the final PCB dechlorination metabolites. The microbial community compositions in MP biofilms were not significantly different (P > 0.05) from those in suspension culture, although possessing greater Dehalococcoides abundance (0.52-0.81% in MP biofilms; 0.03-0.12% in suspension culture). The co-occurrence network analysis revealed that the presence of MPs attenuated microbial synergistic interactions in the dechlorinating culture systems, which may contribute to the inhibitory effect on microbial PCB dechlorination. These findings are important for comprehensively understanding microbial dechlorination behavior and the environmental fate of PCBs in environments with co-existing PCBs and MPs and for guiding the application of in situ PCB bioremediation.

Keywords: Biofilm on microplastics; Commercial PCB mixture; Dehalococcoides; Microbial reductive dechlorination; Microplastics.

MeSH terms

Aroclors
Biodegradation, Environmental
Chlorine / metabolism
Chloroflexi* / metabolism
Geologic Sediments
Microplastics
Plastics / metabolism
Polychlorinated Biphenyls* / metabolism

Substances

Aroclors
Microplastics
Plastics
aroclor 1260
Chlorine
Polychlorinated Biphenyls