title: Effects of benthic organism Tubifex tubifex on hexachlorocyclohexane isomers transfer and distribution into freshwater sediment.
abstract: In this study, bioaccumulation and elimination of HCHs in tubifex, and the distribution of HCHs in overlying water and sediment, were studied during a 10-d experiment. A sensitive method was developed for the determination of HCHs in samples based on gas chromatograph (GC) equipped with a nickel-63 electron capture detector (μECD). The limit of detection (LOD) was 0.35 µg/kg for α-HCH and 0.82 µg/kg for β-HCH. Tubifex accumulated HCHs rapidly, and the curves were approximately M-type. The highest level was reached on the 7th day, with 0.34 mg/kg(wwt) for α-HCH and 0.87 mg/kg(wwt) for β-HCH in worms. The AFs of β-HCH in tubifex were higher than those of α-HCH. Moreover, the existence of tubifex significantly reduced β-HCH fluxes from the overlying water to sediment by uptake or degradation and decreased the concentrations of β-HCH in the sediment, but it had little influence on α-HCH fluxes. Moreover, enantioselectivity of α-HCH enantiomers was not observed in tubifex, whether in the bioaccumulation or elimination experiments. At the end of the elimination experiment, approximately 80% and 70% of α-HCH and β-HCH were eliminated, and the depuration half-lives were 4.43 and 5.39 days, respectively.
authors.affiliation: Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Yuanmingyuan west road 2, Beijing 100193, China; Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Di
authors.affiliation: Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Cheng
authors.affiliation: Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Yuanmingyuan west road 2, Beijing 100193, China; Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, China.
authors.forename: Li
authors.initials: L
authors.lastname: Chen
authors.affiliation: Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Yuanmingyuan west road 2, Beijing 100193, China; Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, China.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Zhou
authors.affiliation: Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, China. Electronic address: lingyinzi1201@gmail.com.
authors.forename: Jinling
authors.initials: J
authors.lastname: Diao
mesh_terms: D000818:Animals; D001673:Biodegradation, Environmental; D005618:Fresh Water / Q000737:chemistry*; D019015:Geologic Sediments / Q000737:chemistry*; D001556:Hexachlorocyclohexane / Q000032:analysis*; D009835:Oligochaeta / Q000378:metabolism*; D013237:Stereoisomerism; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D014874:Water Pollutants, Chemical; C040534:alpha-hexachlorocyclohexane; D001556:Hexachlorocyclohexane; C023888:beta-hexachlorocyclohexane
keywords: Bioaccumulation; Elimination; HCHs; Sediment; Tubifex tubifex