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

WATER RESEARCH

卷:182

Article

Huang, Chenchen^1,2,3  Zeng, Yanhong^1,2  Luo, Xiaojun^1,2  Ren, Zihe^1,2,3  Lu, Qihong⁴  Tian, Yankuan^1,2  Gao, Shutao^1,2  Wang, Shanquan⁵  Harrad, Stuart⁶  Mai, Bixian^1,2 

[1] Chinese Acad Sci, Guangzhou Inst Geochem, State Key Lab Organ Geochem, Guangzhou 510640, Peoples R China

[2] Chinese Acad Sci, Guangzhou Inst Geochem, Guangdong Key Lab Environm Protect & Resources Ut, Guangzhou 510640, Peoples R China

[3] Univ Chinese Acad Sci, Beijing 100049, Peoples R China

[4] Sun Yat Sen Univ, Sch Environm Sci & Engn, Guangzhou, Peoples R China

[5] Guangdong Prov Key Lab Environm Pollut Control &, Guangzhou, Peoples R China

[6] Univ Birmingham, Sch Geog Earth & Environm Sci, Birmingham B15 2TT, W Midlands, England

关键词: Polychlorinated biphenyls;    Microbial degradation;    Sediment;    A multiple-line-of-evidence approach;    Compound-specific isotope analysis;   

DOI  :  10.1016/j.watres.2020.115977

来源: Elsevier

【 摘 要 】

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 delta C-13 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 (Delta delta C-13 > 1 parts per thousand) of PCB congeners were observed, confirming that in situ degradation occurred in the sediment cores. The progressive enrichment in (13)C( )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. (C) 2020 Elsevier Ltd. All rights reserved.

【 授权许可】

Free