Determination of Chlorpyrifos and Diazinon Bioconcentrated in Fish Tissues by Gas Chromatography-mass Spectrometry

Determination of chlorpyrifos and diazinon residues in fish tissues by gas chromatography-mass spectrometry(GC-MS) was developed,and the method was then applied in the analysis of bioconcentration of chlorpyrifos and diazinon in carp fish(Cyprinus carpio Linnaeus)organs.The two pesticides in fish muscle,liver and gill were extracted by homogenizing in acetonitrile,cleaned-up by florisil column,and quantified by GC-MC in selected ion monitoring(SIM) mode.The recoveries were 80%-105% for chlorpyrifos and 82%-100% for diazinon in fish muscle,liver and gill,respectively,with the fortified concentration of 0.05-1.00 mg/kg.The lowest quantification concentration for chlorpyrifos and diazinon were 0.001 mg/kg and 0.005 mg/kg respectively.After 10 d cultivation in the chlorpyrifos and diazinon contaminated water,high levels of both pesticides residue in the carp muscle,liver and gill were found,and the concentrations of both pesticides in the gill were the highest among the three tested organs.Chlorpyrifos was more accumulated in the carp fish organs than diazinon.When the concentrations of chlorpyrifos and diazinon in water were 0.013-0.140 mg/L and 0.13-1.10 mg/L,the calculated bioconcentraton factors of fish musle,liver and gill for chlorpyrifos were 100.23-277.98 L/kg,120.51-264.43 L/mg and 159.40-534.65 L/kg,and for diazinon were 18.04-64.22 L/kg,24.04-46.77 L/kg and 45.92-65.79 L/kg.