Development of A Multi Residue Method for Determination of Pesticide Residues in Some High Oil Content Agricultural Products

Abstract

Pesticides are chemical compounds used to enhance food production. Unfortunately, pesticides have toxic effects on humans and animals through the consumption of agricultural products. Sesame and peanuts were fatty heavy matrices that couldn’t be easily extracted by most known extraction methods. The developed method was optimized and validated for the simultaneous determination of 377 pesticide residues in sesame and 388 pesticides in peanuts depending on a modification in the most common “Quick Easy Cheap Effective Rugged and Safe (QuEChERS)” extraction method. The detection and quantification of these pesticide residues was carried out using both high performance liquid chromatography triple quadruple mass spectrometry (LC–MS/MS) and gas chromatography triple quadruple mass spectrometry (GC–MS/MS). The studied method was validated according to SANTE guideline 11312/2021 with different validation parameters such as limit of quantitation (LOQ), linearity, matrix effect, precision and trueness. LOQs of the studied method were ranged from 0.01- 0.05 mg/kg for all targeted pesticides. The linearity range for LC–MS/MS was in the range of 0.001– 0.1 μg/ml and for GC–MS/MS was in the range of 0.002–0.5 μg/ml with R2 > 0.99. The suppression and enhancement effects on the pesticide concentrations due to the sesame and peanuts components, called the matrix effect which were compensated during the analysis by using the standard addition technique. The precision and trueness of the method were determined from recovery experiments on 6 replicates of spiked blank samples in each commodity at 3 validation levels 0.01, 0.05, and 0.1 mg/kg respectively. Acceptable recoveries in the range of 70–120% and relative standard deviations (RSD %) less than 20% for all the tested pesticides were obtained. The developed method can be easily used in the routine analysis of pesticide residues in sesame and peanuts.