Tracing the sources and microbial degradation of PCBs in field sediments by a multiple-line-of-evidence approach including compound-specific stable isotope analysis

Research output: Contribution to journalArticlepeer-review

Authors

  • Chenchen Huang
  • Yanhong Zeng
  • Xiaojun Luo
  • Zihe Ren
  • Qihong Lu
  • Yankuan Tian
  • Shutao Gao
  • Shanquan Wang
  • Bixian Mai

Colleges, School and Institutes

External organisations

  • University of Chinese Academy of Sciences
  • Chinese Academy of Sciences
  • Sun Yat-sen University

Abstract

Comprehensive monitoring is crucial for tracing micropollutants in the natural environment. To better evaluate the sources and natural attenuation of polychlorinated biphenyls (PCBs), three composite sediment cores were sampled from a closed pond near e-waste recycling plants, and a multiple-line-of-evidence approach (MLEA) including quantification, enantiomer analysis, microbial community profiling, and compound-specific isotope analysis (CSIA) was used to investigate the fate of PCBs in sediment cores. The difference in the maximum PCB concentrations and associated depths between sites 1/2 and 3 and the corresponding significant (p < 0.01) difference in δ13C values strongly indicated two different PCB inputs at sites 1/2 and 3. A significant (p < 0.01) negative correlation between the variation in chlorine per biphenyl (CPB) and Log the abundance of Dehalococcoides/total molar concentration of PCBs (Log Dhc/TPCB) along the cores suggested that different degrees of PCB degradation occurred and that Dehalococcoides likely participated in PCB degradation in these sediments. Nonracemic compositions and pronounced stable carbon isotope fractionation (Δδ13C > 1‰) of PCB congeners were observed, confirming that in situ degradation occurred in the sediment cores. The progressive enrichment in 13C with increasing core depth suggested strengthened microbial degradation of the residual congener pools. The results of this study suggested that MLEA analysis of PCBs can provide reliable information to better monitor the sources and fate of these compounds in the environment.

Bibliographic note

Copyright © 2020 Elsevier Ltd. All rights reserved.

Details

Original languageEnglish
Article number115977
Number of pages8
JournalWater Research
Volume182
Early online date27 May 2020
Publication statusPublished - 1 Sep 2020

Keywords

  • Polychlorinated biphenyls, Microbial degradation, Sediment, A multiple-line-of-evidence approach, Compound-specific isotope analysis