Determination of twenty organophosphorus pesticides in blood serum by gas chromatography-tandem mass spectrometry

A large number of organophosphorus (OP) pesticides are used globally, and the effects of OP pesticides on human health have attracted attention. However, methods focusing on the determination of various OP pesticides in human blood serum are still scarce, and the exposure level of various OP pesticides in humans remains largely unknown. We have developed a method for the quantification of 20 OP pesticides in human blood serum simultaneously. The determination was performed using solid-phase extraction with a small blood serum sample volume (200 mu L) and gas chromatographic analysis with triple quadrupole mass spectrometry (GC-MS/MS). Among the 20 pesticides, limits of detection ranged from 0.01 to 2.70 ng mL(-1); limits of quantitation ranged from 0.05 to 9.00 ng mL(-1); linearity ranged from 0.02 to 135.00 ng mL(-1); recoveries ranged from 90 to 120%; intra-day and inter-day relative standard deviations were mostly less than 15% at 2.70 and 27.00 ng mL(-1) in the spiked blood serum samples. This method was further used for the determination of OP pesticides in 160 human blood serum samples, which generated the first-hand data regarding the OP pesticide exposure profile in Chinese adults without occupational exposure.