THE ANALYSIS OF COMMON METABOLITES OF ORGANOPHOSPHORUS PESTICIDES IN URINE BY GAS-CHROMATOGRAPHY MASS-SPECTROMETRY

Most organophosphorus pesticides may be metabolized to yield some comm on phosphates in human or in animals, and these metabolites may be use d as the exposure biomarkers to pesticides. In this study, we develope d the extraction method of four phosphate metabolites from the spiked human urine in high recovery by the solid phase extraction with a reve rse-phase cartridge (cyclohexyl silica) followed by the elution with m ethanol. The extracted urinary metabolites were derivatized with xamet hyldisilazane/trimethyl-chlorosilane/pyridine (2:1:10, v/v/v) and iden tified by gas chromatography/mass spectrometry. Calibration curve obta ined from each metabolite standard using by GC/MS/SIM has shown good l inearity and detection limits of metabolites were the range of 0.05-0. 1 mu g/ml in urine. Phenthoate, one of the organophosphorus pesticides , was orally administrated to rats. Four metabolites were detected in the rat urine. The results of this study may be applied to development of exposure biomarkers for monitoring of environmental pollutants.