title: Characterization of anthropogenic impacts in a large urban center by examining the spatial distribution of halogenated flame retardants.
abstract: Anthropogenic impacts have continuously intensified in mega urban centers with increasing urbanization and growing population. The spatial distribution pattern of such impacts can be assessed with soil halogenated flame retardants (HFRs) as HFRs are mostly derived from the production and use of various consumer products. In the present study, soil samples were collected from the Pearl River Delta (PRD), a large urbanized region in southern China, and its surrounding areas and analyzed for a group of HFRs, i.e., polybrominated diphenyl ethers (PBDEs), decabromodiphenyl ethane, bis(hexachlorocyclopentadieno)cyclooctane (DP) and hexabromobenzene. The sum concentrations of HFRs and PBDEs were in the ranges of 0.66-6500 and 0.37-5700 (mean: 290 and 250) ng g(-1) dry weight, respectively, around the middle level of the global range. BDE-209 was the predominant compound likely due to the huge amounts of usage and its persistence. The concentrations of HFRs were greater in the land-use types of residency, industry and landfill than in agriculture, forestry and drinking water source, and were also greater in the central PRD than in its surrounding areas. The concentrations of HFRs were moderately significantly (r(2) = 0.32-0.57; p < 0.05) correlated with urbanization levels, population densities and gross domestic productions in fifteen administrative districts. The spatial distribution of DP isomers appeared to be stereoselective as indicated by the similarity in the spatial patterns for the ratio of anti-DP versus the sum of DP isomers (fanti-DP) and DP concentrations. Finally, the concentrations of HFRs sharply decreased with increasing distance from an e-waste recycling site, indicating that e-waste derived HFRs largely remained in local soil.
authors.affiliation: State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Yan-Li
authors.initials: YL
authors.lastname: Wei
authors.affiliation: School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China. Electronic address: blj727722@163.com.
authors.forename: Lian-Jun
authors.initials: LJ
authors.lastname: Bao
authors.affiliation: State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Chen-Chou
authors.initials: CC
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China.
authors.forename: Eddy Y
authors.initials: EY
authors.lastname: Zeng
mesh_terms: D001969:Bromobenzenes / Q000032:analysis*; D002681:China; D002947:Cities; D004784:Environmental Monitoring; D005411:Flame Retardants / Q000032:analysis*; D055768:Halogenated Diphenyl Ethers / Q000032:analysis*; D045483:Rivers; D012989:Soil Pollutants / Q000032:analysis*; D014507:Urbanization; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D001969:Bromobenzenes; D005411:Flame Retardants; D055768:Halogenated Diphenyl Ethers; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; C017363:hexabromobenzene
keywords: Anthropogenic impact; Halogenated flame retardant; Pearl River Delta; Soil; Urbanization