DETECTION OF ORGANOPHOSPHATE PESTICIDES IN HUMAN-BODY FLUIDS BY HEADSPACE SOLID-PHASE MICROEXTRACTION (SPME) AND CAPILLARY GAS-CHROMATOGRAPHY WITH NITROGEN-PHOSPHORUS DETECTION

Organophosphate pesticides have been found extractable by headspace so lid-phase microextraction (SPME), and the best conditions of their ext raction from human whole blood and urine samples have been investigate d. The body fluid samples containing nine pesticides (IBP, methyl para thion, fenitrothion, malathion, fenthion, isoxathion, ethion, EPN and phosalone) were heated at 100 degrees C in a septum-capped vial in the presence of various combinations of acid and salts, and SPME fiber wa s exposed to the headspace of the vial to allow adsorption of the pest icides before capillary gas chromatography (GC) with nitrogen-phosphor us detection. The heating with distilled water/HCl/(NH4)(2)SO4/NaCl an d with distilled water/HCl gave the best results for urine and whole b lood, respectively. Recoveries of the nine pesticides were 0.8-10.6% e xcept for phosalone (0.03%) for whole blood, and 3.8-40.2% for urine. The calibration curves for the pesticides showed linearity in the rang e of 50-400 ng/0.5 mL for whole blood except for malathion (100-400 ng /0.5 mL whole blood) and 7.5-120 ng/0.5 mL for urine except for phosal one (15-120 ng/0.5 mL urine) with detection limits of 2.2-40 ng/0.5 mL for whole blood and 0.8-12 ng/0.5 mL for urine.