title: Enantioseletive bioaccumulation and metabolization of diniconazole in earthworms (Eiseniafetida) in an artificial soil.
abstract: Degradation and enantioselective bioaccumulation of diniconazole in earthworms (Eiseniafetida) in artificial soil was investigated using liquid chromatography-tandem mass spectrometry (LC-MS/MS) method under laboratory condition. Three exposure concentrations (1 mg/kg, 10 mg/kg and 25 mg/kg) of diniconazole in soil (dry weight) to earthworms were used. The uptake kinetics fitted the first-order kinetics well. The bioaccumulation factors (BAF) of R, S isomers were 6.6046 and 8.5115 in 25 mg/kg dose exposure, 2.6409 and 2.9835 in 10mg/kg dose exposure, 1.7784 and 2.0437 in 1 mg/kg dose exposure, respectively. Bioaccumulation of diniconazole in earthworm tissues was enantioselective with a preferential accumulation of S-diniconazole and the enantiomer fractions were about 0.45-0.50 in all three level dose exposures. In addition, it was obvious that both R-diniconazole and S-diniconazole had bioaccumulation effect in earthworm. Diniconazole was metabolized to 1,2,4-triazole, (E)-3-(1H-1,2,4-triazol-1-yl) acrylaldehyde, (E, S)-4-(2, 4-dichlorophenyl)-2, 2-dimethyl-5-(1H-1,2,4-triazol-1-yl)pent-4-ene-1,3-diol, and (E)-4-(2, 4-dichlorophenyl)-3-hydroxy-2,2-dimethyl-5-(1H-1,2,4-triazol-1-yl) pent-4-enoic acid in earthworms; the metabolites of 1,2,4-triazole and (E)-3-(1H-1,2,4-triazol-1-yl)acrylaldehyde could be detected in soil as well.
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Huili
authors.initials: H
authors.lastname: Wang
authors.forename: Jinhui
authors.initials: J
authors.lastname: Chen
authors.forename: Bao-Yuan
authors.initials: BY
authors.lastname: Guo
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Li
mesh_terms: D000818:Animals; D002853:Chromatography, Liquid; D009835:Oligochaeta / Q000378:metabolism*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000378:metabolism*; D013237:Stereoisomerism; D053719:Tandem Mass Spectrometry; D014230:Triazoles / Q000032:analysis / Q000378:metabolism*
chemical_list: D012987:Soil; D012989:Soil Pollutants; D014230:Triazoles; C049346:diniconazole
keywords: Bioaccumulation; Diniconazole; Earthworm; Enantioselcetivity; Metabolization