title: Short-chain chlorinated paraffins in the soils of two different Chinese cities: Occurrence, homologue patterns and vertical migration.
abstract: Short-chain chlorinated paraffins (SCCPs) are candidate persistent organic pollutants (POPs) that are under review by the Stockholm Convention. China is currently the largest producer and consumer of chlorinated paraffins (CPs). To study the environmental behavior and fate of SCCPs in the soils of urban and suburban regions, the SCCP concentrations in 88 topsoils and 15 soil columns from land of different use types (e.g., woodland, vegetable field, paddy field and greenbelt) from Guangzhou and Chengdu have been determined. The SCCP concentrations in topsoils from Guangzhou (range: 1.45-25.5ngg(-1) dry weight (dw), average: 10.3ngg(-1) dw) were much higher than those from Chengdu (range: 0.218-3.26ngg(-1) dw, average: 1.43ngg(-1) dw). When compared to previously reported SCCP levels for topsoils from other areas, the SCCP concentrations measured in the present work were quite low. Much higher SCCP concentrations were observed in the greenbelt topsoils from Chengdu relative to the values measured from woodlands and vegetable and paddy fields. The composition profiles suggest that C10Cl6-10 and C11-13Cl6-8 were the major groups of SCCPs in topsoils from the woodlands and vegetable and paddy fields in Guangzhou and Chengdu. Vertical variations of the SCCP concentrations in the soil columns suggest that less chlorinated SCCPs (Cl5-6-SCCPs) are more capable of migrating to the deeper-layer soils than more chlorinated ones (Cl9-10-SCCPs). The SCCP concentrations displayed little dependence on organic matter (OM) for most topsoils (p>0.05), indicating that OM is not the controlling factor in the distribution of SCCPs in the soils.
  
  
  
  This study analyzed the occurrence, homologue patterns and vertical migration of SCCPs in the topsoils of two Chinese cities with different industrial structures and climate conditions.
authors.affiliation: Urban Environment and Ecology Research Center, South China Institute of Environmental Sciences (SCIES), Ministry of Environmental Protection, Guangzhou 510655, China; School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006, China.
authors.forename: Yumei
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Urban Environment and Ecology Research Center, South China Institute of Environmental Sciences (SCIES), Ministry of Environmental Protection, Guangzhou 510655, China; College of Resource and Environment, Chengdu University of Information Technology, Chengdu 610225, China.
authors.forename: Laiguo
authors.initials: L
authors.lastname: Chen
authors.affiliation: Urban Environment and Ecology Research Center, South China Institute of Environmental Sciences (SCIES), Ministry of Environmental Protection, Guangzhou 510655, China; College of Resource and Environment, Chengdu University of Information Technology, Chengdu 610225, China.
authors.forename: Yongbin
authors.initials: Y
authors.lastname: Feng
authors.affiliation: College of Resource and Environment, Chengdu University of Information Technology, Chengdu 610225, China.
authors.forename: Zhixiang
authors.initials: Z
authors.lastname: Ye
authors.affiliation: School of Environment and Safety, Taiyuan University of Science and Technology, Taiyuan 030024, China.
authors.forename: Qiusheng
authors.initials: Q
authors.lastname: He
authors.affiliation: Urban Environment and Ecology Research Center, South China Institute of Environmental Sciences (SCIES), Ministry of Environmental Protection, Guangzhou 510655, China.
authors.forename: Qianhua
authors.initials: Q
authors.lastname: Feng
authors.affiliation: Urban Environment and Ecology Research Center, South China Institute of Environmental Sciences (SCIES), Ministry of Environmental Protection, Guangzhou 510655, China.
authors.forename: Xian
authors.initials: X
authors.lastname: Qing
authors.affiliation: Urban Environment and Ecology Research Center, South China Institute of Environmental Sciences (SCIES), Ministry of Environmental Protection, Guangzhou 510655, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Liu
authors.affiliation: Urban Environment and Ecology Research Center, South China Institute of Environmental Sciences (SCIES), Ministry of Environmental Protection, Guangzhou 510655, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Gao
mesh_terms: D002681:China; D002947:Cities / Q000706:statistics & numerical data; D004784:Environmental Monitoring; D010232:Paraffin / Q000032:analysis*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis*
chemical_list: D012987:Soil; D012989:Soil Pollutants; D010232:Paraffin
keywords: Composition profile; Organic matter; Short-chain chlorinated paraffins (SCCPs); Soil; Vertical variation