Rapid and sensitive analytical procedure for biomonitoring of organophosphate pesticide metabolites in human urine samples using a vortex-assisted salt-induced liquid-liquid microextraction technique coupled with ultra-high-performance liquid chromatography/tandem mass spectrometry.

Abstract

Organophosphate pesticides (OPPs) are the most commonly used insecticides around the world in various agricultural and domestic practices, and humans are frequently exposed to these hazardous insecticides that can lead to several chronic health effects. Therefore, a fast and sensitive analytical method is required for biomonitoring the markers of OPPs in humans for exposure estimation. In this study, a fast and sensitive analytical procedure was developed for the determination of the metabolites of OPPs in human urine samples. Metabolites of OPPs were extracted from 2 mL of urine sample using a novel vortex-assisted salt-induced liquid-liquid microextraction (VA-SI-LLME) technique, and the preconcentrated metabolites were analyzed by ultra-high-performance liquid chromatography/tandem mass spectrometry (UHPLC/MS/MS). Various factors affecting the efficiency of VA-SI-LLME were thoroughly investigated. The metabolites of OPPs exhibited very good linearity over the concentration range between 0.05 and 50 ng mL-1 with coefficient (r2 ) values ranging between 0.9986 and 0.9999. The method showed excellent sensitivity with detection limits ranging from 0.01 to 0.03 ng mL-1 and quantification limits from 0.03 to 0.05 ng mL-1 . The developed method was applied to the analysis of real samples and the recoveries ranged between 85.0 and 114.1% with related standard deviations <5%. The results showed the VA-SI-LLME/UHPLC/MS/MS method to be a simple, rapid, sensitive, and selective analytical procedure for the biomonitoring of the metabolites of OPPs in humans. This efficient and cost-effective analytical method could be a potential alternative method for the biomonitoring of the metabolites of pesticides in humans.