title: Distribution and enantiomeric profiles of organochlorine pesticides in surface sediments from the Bering Sea, Chukchi Sea and adjacent Arctic areas.
abstract: The spatial distribution, compositional profiles, and enantiomer fractions (EFs) of organochlorine pesticides (OCPs), including hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs), and chlordanes (CHLs), in the surface sediments in the Bering Sea, Chukchi Sea and adjacent areas were investigated. The total concentrations of DDTs, HCHs and CHLs varied from 0.64 to 3.17 ng/g dw, 0.19-0.65 ng/g dw, and 0.03-0.16 ng/g dw, respectively. No significant difference was observed between the Bering Sea and Chukchi Sea for most pollutants except for trans-CHL, ΣCHLs (sum of trans- and cis-chlordane) and p,p'-DDD. Concentration ratios (e.g., α-HCH/γ-HCH, o,p'-DDT/p,p'-DDT) indicated that the contamination in the studied areas may result from inputs from multiple sources (e.g., historical usage of technical HCHs as well as new input of dicofol). Chiral analysis showed great variation in the enantioselective degradation of OCPs, resulting in excess of (+)-enantiomer for α-HCH in thirty of the 32 detectable samples, preferential depletion of (-)-enantiomer for o,p'-DDT in nineteen of the 35 detectable samples, and nonracemic in most samples for trans- and cis-chlordane. The ecological risks of the individual OCPs as well as the mixture were assessed based on the calculation of toxic units (TUs), and the results showed the predominance of DDT and γ-HCH in the mixture toxicity of the sediment. Overall, the TUs of OCPs in sediments from both the Bering and Chukchi Seas are less than one, indicating low ecological risk potential.
authors.affiliation: College of Materials Science and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, PR China.
authors.forename: Meiqing
authors.initials: M
authors.lastname: Jin
authors.affiliation: College of Environment, Zhejiang University of Technology, Hangzhou, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Fu
authors.affiliation: Key Laboratory of Marine Ecosystem and Biogeochemistry, The Second Institute of Oceanography, State Oceanic Administration, Hangzhou, PR China.
authors.forename: Bin
authors.initials: B
authors.lastname: Xue
authors.affiliation: College of Environment, Zhejiang University of Technology, Hangzhou, PR China. Electronic address: sszhou@zjut.edu.cn.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Zhou
authors.affiliation: College of Environment, Zhejiang University of Technology, Hangzhou, PR China.
authors.forename: Lina
authors.initials: L
authors.lastname: Zhang
authors.affiliation: College of Environment, Zhejiang University of Technology, Hangzhou, PR China; School of Public Health, University of Illinois at Chicago, Chicago, United States.
authors.forename: An
authors.initials: A
authors.lastname: Li
mesh_terms: D000818:Animals; D001110:Arctic Regions; D002681:China; D003634:DDT / Q000032:analysis; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D001556:Hexachlorocyclohexane / Q000032:analysis; D006843:Hydrocarbons, Chlorinated / Q000032:analysis* / Q000737:chemistry*; D009792:Oceans and Seas; D010573:Pesticide Residues / Q000032:analysis / Q000737:chemistry; D010575:Pesticides / Q000032:analysis* / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry*
chemical_list: D006843:Hydrocarbons, Chlorinated; D010573:Pesticide Residues; D010575:Pesticides; D014874:Water Pollutants, Chemical; C040534:alpha-hexachlorocyclohexane; D001556:Hexachlorocyclohexane; D003634:DDT
keywords: Chiral; Chlordanes; Dichlorodiphenyltrichloroethanes; Hexachlorocyclohexanes; Toxic units (TUs)