title: Sequestration of organochlorine pesticides in soils of distinct organic carbon content.
abstract: In the present study, five soil samples with organic carbon contents ranging from 0.23% to 7.1% and aged with technical dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) for 15 months were incubated in a sealed chamber to investigate the dynamic changes of the OCP residues. The residues in the soils decreased over the incubation period and finally reached a plateau. Regression analysis showed that degradable fractions of OCPs were negatively correlated with soil organic carbon (SOC) except for α-HCH, while no correlation was found between degradation rate and SOC, which demonstrated that SOC content determines the OCP sequestration fraction in soil. Analysis of the ratio of DDT and its primary metabolites showed that, since it depends on differential sequestration among them, magnitude of (p,p'-DDE + p,p'-DDD)/p,p'-DDT is not a reliable criterion for the identification of new DDT sources.
authors.affiliation: Laboratory for Earth Surface Processing, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
authors.forename: Na
authors.initials: N
authors.lastname: Zhang
authors.forename: Yu
authors.initials: Y
authors.lastname: Yang
authors.forename: Shu
authors.initials: S
authors.lastname: Tao
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.forename: Ke-Lu
authors.initials: KL
authors.lastname: Shi
mesh_terms: D002244:Carbon / Q000737:chemistry / Q000378:metabolism; D002681:China; D003634:DDT / Q000032:analysis / Q000378:metabolism*; D003633:Dichlorodiphenyl Dichloroethylene / Q000032:analysis / Q000378:metabolism; D003632:Dichlorodiphenyldichloroethane / Q000032:analysis / Q000378:metabolism; D004784:Environmental Monitoring; D001556:Hexachlorocyclohexane / Q000032:analysis / Q000378:metabolism*; D007306:Insecticides / Q000032:analysis / Q000378:metabolism; D009930:Organic Chemicals / Q000737:chemistry / Q000378:metabolism; D010573:Pesticide Residues / Q000032:analysis / Q000378:metabolism*; D012987:Soil / Q000032:analysis / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism
chemical_list: D007306:Insecticides; D009930:Organic Chemicals; D010573:Pesticide Residues; D012987:Soil; D012989:Soil Pollutants; D003633:Dichlorodiphenyl Dichloroethylene; D001556:Hexachlorocyclohexane; D002244:Carbon; D003634:DDT; D003632:Dichlorodiphenyldichloroethane