LAUSR

Detecting pesticide residues in human serum is a challenging process. This study developed and validated a method for the extraction and recovery of residues of multiple classes of pesticides from serum using one reagent. Salt-assisted acetonitrile extraction and HPLC with quadrupole time of flight MS/MS were used to quantitate 34 pesticides classified in nine groups of chemicals in human serum samples, which are frequently detected in food. The recoveries for 33 of analyzed pesticides ranged from 86% to 112% with relative standard deviations were below 15%. The limits of quantitation and linearity of 31 of the pesticides were 1 μg/L and > 0.990, respectively. That the lower limit of quantitation has been reported in the literature particularly for multi-classes pesticide mixtures in human serum. The salt-acetonitrile reagent allowed to achieve good recoveries and detection limits, which could be attributed to salt altering the solvent polarity, preferentially collecting the organic phase in the solution, and promoting the extraction. The developed method was applied for two organophosphate pesticide metabolites, diethylphosphate and 3,5,6-trichloro-2-pyridinol, in serum from rats that were fed a non-lethal quantity of chlorpyrifos. The concentrations of these two were 252.18 ± 15.47 and 0.63 ± 0.23 μg/L, respectively. This article is protected by copyright. All rights reserved.