title: Spatial and vertical distribution of short chain chlorinated paraffins in soils from wastewater irrigated farmlands.
abstract: Chlorinated paraffins (CPs) are one of the most complex groups of halogenated contaminants in the environment. However, studies of short chain CPs (SCCPs) in China are very scarce. In this study, the concentrations and distribution of SCCPs in farm soils from a wastewater irrigated area in China were investigated. SCCPs were detected in all topsoil samples, with the sum of the concentrations (ΣSCCPs) in the range of 159.9-1450 ng/g (dry weight, dw). A noticeable spatial trend and specific congener distribution were observed in the wastewater irrigated farmland. Soil vertical profiles showed that ΣSCCP concentrations below the plowed layer decreased exponentially and had a significant positive relationship (R(2) > 0.83) with total organic carbon in soil cores. Furthermore, soil vertical distributions indicated that lower chlorinated (Cl(5-6)) and shorter chain (C(10-12)) congeners are more prone to migrate to deeper soil layers compared to highly chlorinated and longer chain congeners. This work demonstrated that effluents from sewage treatment plants (STPs) could be a significant source of SCCPs to the ambient environment and wastewater irrigation can lead to higher accumulation of SCCPs in farm soils.
authors.affiliation: State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Lixi
authors.initials: L
authors.lastname: Zeng
authors.forename: Thanh
authors.initials: T
authors.lastname: Wang
authors.forename: Wenya
authors.initials: W
authors.lastname: Han
authors.forename: Bo
authors.initials: B
authors.lastname: Yuan
authors.forename: Qian
authors.initials: Q
authors.lastname: Liu
authors.forename: Yawei
authors.initials: Y
authors.lastname: Wang
authors.forename: Guibin
authors.initials: G
authors.lastname: Jiang
mesh_terms: D057914:Agricultural Irrigation; D004784:Environmental Monitoring; D006843:Hydrocarbons, Chlorinated / Q000032:analysis*; D010232:Paraffin / Q000032:analysis*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D006843:Hydrocarbons, Chlorinated; D012987:Soil; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; D010232:Paraffin