Advanced Search
Pollution of heavy metals and polychlorinated biphenyls by improper e-waste dismantling activities and its ecotoxicological effect
Received:December 16, 2016  
View Full Text  View/Add Comment  Download reader
KeyWord:e-waste;soil enzyme;microbial diversity;PCR-DGGE
Author NameAffiliationE-mail
ZHANG Jin-lian School of Environment and Energy, South China University of Technology, Guangzhou 510006, China  
DING Jiang-feng School of The Environment, Guangxi University, Nanning 530004, China  
LIN Hao-zhong School of Environment and Energy, South China University of Technology, Guangzhou 510006, China  
DANG Zhi School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China 
 
YI Xiao-yun School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China 
 
LU Gui-ning School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China 
lutao@scut.edu.cn 
Hits: 2148
Download times: 2567
Abstract:
      Longtang Town and Shijiao Town in Qingyuan City, Guangdong Province, South China, have been known for their improper e-waste importing and recycling, and their crude recycling activities have led to serious contamination of the surrounding environment. In the present work, enzyme activities and microbial communities of soil samples at the open burning site (OBS) and near the dismantling workshops (NDW), as well as enzyme activities and microbial communities of samples of farmland soil (FS) around the dismantling workshops, were analyzed. Results showed that different enzymes had different responses to pollution by heavy metals and PCBs. Significant negative correlations between acid phosphatase activity and concentration of Pb, Cu, Zn, Cd, or PCBs in the soil samples were observed (P<0.01 or P<0.05). Acid phosphatase was the most sensitive indicator of the reactions of five different enzymes to soil contamination by heavy metals and PCBs. Soil enzyme activities were not only influenced by pollutants, but also closely related to soil physical-chemical qualities such as soil nutrients, pH, and so on. Results of polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) experiments demonstrated that the Shannon index varied from 1.946 to 2.485 at different sites, and the indices at OBS, NDW, and farmland around the dismantling workshops were lower than those at farmland sites far away from the central dismantling area. A higher Shannon index indicates a more diversified bacterial community, therefore, the above result partly implied the damage to local soil microorganisms by pollution from improper e-waste dismantling activities. Proteobacteria was the most abundant bacterial lineage (60%). Some PCR-DGGE band sequences were highly similar with 16S rRNA genes from heavy metal-resistant microorganisms and PCB- and PAH-degrading microorganisms.