title: Changes of lead speciation and microbial toxicity in soil treated with repeated Pb exposure in the presence of BDE209.
abstract: Lead (Pb) and decabromodiphenyl ether (BDE209) are main pollutants at electric waste (e-waste) recycling sites (EWRSs), and their joint toxicological effects have received extensive attention. Frequently, soil pollution at EWRSs usually results from the occurrence of repeated single or multiple pollution events, with continuous impacts on soil microorganisms. Therefore, a laboratory incubation study was conducted to determine Pb bioavailability and microbial toxicity in repeated Pb-polluted soil in the presence of BDE209 for the first time. We evaluated the impacts of repetitive exposure trials on chemical fractions of Pb, and the results showed that repeated single Pb pollution event resulted in an increase of carbonates fraction of Pb, which was different from one-off single Pb exposure. Moreover, one-off Pb-treated groups exhibited higher I R (reduced partition index) values on day 30 and all treatments remained the same I R level at the end of incubation period. The parameters of microbial toxicity were well reflected by soil enzymes. During the entire incubation, the dehydrogenase and urease activities were significantly inhibited by Pb (P < 0.01), and BDE209 supply could weaken the adverse influence. Additionally, significant correlations between available or metastable Pb and the two soil enzymes were clearly observed (P < 0.05 or 0.01). Such observations would provide useful information for ecological effects of Pb and BDE209 at EWRSs.
authors.affiliation: State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, Shanghai, 200237, China.|School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Zhang
authors.affiliation: State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, Shanghai, 200237, China. wzhang@ecust.edu.cn.|School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China. wzhang@ecust.edu.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, Shanghai, 200237, China.|School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China.
authors.forename: Gao
authors.initials: G
authors.lastname: Liu
authors.affiliation: State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, Shanghai, 200237, China.|School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China.
authors.forename: Kuangfei
authors.initials: K
authors.lastname: Lin
authors.affiliation: Shanghai Academy of Environmental Sciences, Shanghai, 200233, China. rongermmfu@163.com.
authors.forename: Rongbing
authors.initials: R
authors.lastname: Fu
mesh_terms: D055768:Halogenated Diphenyl Ethers / Q000633:toxicity; D007854:Lead / Q000633:toxicity*; D059027:Recycling; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis / Q000633:toxicity*
chemical_list: D055768:Halogenated Diphenyl Ethers; D012987:Soil; D012989:Soil Pollutants; D007854:Lead; C010902:decabromobiphenyl ether
keywords: BDE209; Bioavailability; Pb; Soil; Toxicity