Determination of 63 Organophosphrous Pesticides Residues in Pork by Gas Chromatography and Gas Chromatography-Mass Spectrometry

A method for determination of 63 organophosphrous pesticides residues in pork sample was described by solid phase extraction(SPE)/gas chromatography with flame photometric detection(FPD) and gas chromatography-mass spectrometry(GC-MS).The residues were extracted from homogenized tissue with acetonitrile-water assisted by n-hexane,and separated with liquid-liquid partition.The supernatant liquid was cleaned up by SPE(C18 and PSA columns).The separation and determination of analytes were performed by using GC and GC-MS with selected ion monitoring(SIM) mode and external standard method.The conditions of pretreatment and determination were investigated.The method was convenient and rapid.Under the optimal conditions,the detection limits(S/N=10) of pesticides were in the range of 0.001-0.043 mg/kg with the relative standard deviations of 4.1%-13.9%.The recoveries of pesticides from pork sample spiked with mixed standards at 0.16 mg/kg ranged from 70% to 121%.