Development and method validation for determination of 54 pesticides in Okra by LC-MS/MS analysis

Abstract

The presence of pesticide residues in primary and derived agricultural products raises serious health concerns for consumers across the globe. The aim of the present study was to assess the level of pesticide residues in Okra in India. A multi-residue method for the quantification of fifty-four pesticides in okra is described in this work. The present study employed a modified quick, easy cheap, effective rugged and safe (QuEChERS) extraction procedure followed by UHPLC-MS/MS (Ultra-High-Performance Liquid Chromatography coupled to Tandem Mass Spectrometry) analysis. Validation of the method was according to the guidelines given by European Union SANCO/12571/2013. The levels of validation were 10.0, 50.0 and 100 µg kg^-1. The following parameters such as linearity, the limit of detection (LOD) (nearer to 0.005 mg kg^-1) and limit of quantification (LOQ) (nearer to 0.01 mg kg^-1) were set to be acceptable. The trueness of the method for 54 pesticides in all Okra commodities was between 80-110% with satisfactory repeatability and within-run reproducibility except for the pesticide residues such as  Thiamethoxam and Fenamidone. The measurement of uncertainty for each of the pesticide was below 50% and was estimated to be in the range of 5.37% - 10.71%, which meets the criteria established in the SANCO/12571/2013 document (European Union, 2013). This method is concluded to be applicable for the determination of pesticide residues in Okra.