Temporal dynamics of bacterial biofilms and their relationship with heavy metals on expanded polystyrene microplastics

Qun XIE; Yan FENG; Xiangrong XU; Hengxiang LI; Lang LIN; Weiqiong YU; Guanghui ZHU; Nenghao ZHONG; Minhua WU; Kai ZHANG

doi:10.1007/s00343-024-3291-x

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Temporal dynamics of bacterial biofilms and their relationship with heavy metals on expanded polystyrene microplastics

Biofilm on micro- and nano-plastics | Updated：2025-03-21

- Temporal dynamics of bacterial biofilms and their relationship with heavy metals on expanded polystyrene microplastics
- Journal of Oceanology and Limnology Vol. 43, Issue 2, Pages: 528-544(2025)
- Affiliations：
  
  1.Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
  2.Analytical and Testing Center, Guangdong Ocean University, Zhanjiang 524088, China
  3.Sanya Institute of Ocean Eco-Environmental Engineering, Sanya 572000, China
  4.Marine Environmental Engineering Center, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
  5.College of Chemistry and Environmental Science, Guangdong Ocean University, Zhanjiang 524088, China
  6.School of Basic Medicine, Guangdong Medical University, Zhanjiang 524023, China
  7.National Observation and Research Station of Coastal Ecological Environments in Macao, Macao Environmental Research Institute, Macau University of Science and Technology, Macao SAR 999078, China
- Author bio：
  
  xuxr@scsio.ac.cn
- Funds：
- DOI：10.1007/s00343-024-3291-x
  CLC：
- Received：16 May 2023，
  
  Online First：16 February 2024，
  
  Published：01 March 2025
- Accepted：
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XIE Qun,FENG Yan,XU Xiangrong,et al.Temporal dynamics of bacterial biofilms and their relationship with heavy metals on expanded polystyrene microplastics[J].Journal of Oceanology and Limnology,2025,43(02):528-544.
DOI：

XIE Qun,FENG Yan,XU Xiangrong,et al.Temporal dynamics of bacterial biofilms and their relationship with heavy metals on expanded polystyrene microplastics[J].Journal of Oceanology and Limnology,2025,43(02):528-544. DOI： 10.1007/s00343-024-3291-x.

摘要

Abstract

Expanded polystyrene (EPS) is a common type of microplastics (MPs) often found in coastal areas especially aquaculture areas. It is considered as an important site for microbial colonization and biofilm formation

as well as a carrier of pollutants like heavy metals. However

the dynamic changes of bacterial communities attached to EPS and their interaction with heavy metals are still poorly unknown. In this study

a one-year field exposure experiment was conducted at an aquaculture farm near Donghai Island

in Leizhou Bay

Zhanjiang

Guangdong

in South China Sea. The bacterial communities attached to EPS MPs were examined by 16S rDNA high-throughput sequencing

and the relationships between bacterial biofilms and heavy metals were explored. The results show that there were notable seasonal variations in the bacterial diversity of EPS MPs. Species biodiversity was the highest in summer and the lowest in winter. The greatest number of bacterial species and lowest level of uniformity were observed in the spring. The bacterial community structure changed with exposure time

and the most significant difference in the 12-month group (

0.05) was found. The dominant bacterial species attached to EPS MPs were mainly Proteobackteria and Firmicutes at the phylum level

and

Pseudomonas

and

Exiguobacterium

were dominant at the genus level. Furthermore

EPS MPs acted as transport carriers for potential pathogenic bacteria. High correlations were found between bacterial species and the total concentration of heavy metals on EPS MPs

as well as their speciation fractions. Different chemical speciation of heavy metals migrated and altered over seasons within biofilms

which would further exacerbate the ecological risks.

关键词

Keywords

references

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