Validation of Analytical Method for Quantification of Six Pesticide Residues in Dried Chili Powder Using GC-MS/MS

The study describes an analytical method for determination of six pesticide residues namely Quinalphos, Dimethoate, alphaendosulfan, beta-endosulfan, Triazophos and Endosulfan sulfate, in dried chilli using GC-MS/MS (Gas chromatography triple quad mass spectrometer) instrument with modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) sample preparation technique. The developed method was validated with respect to various performance attributes as per SANTE 11312/2021 and was found to be linear within the range from 10 ng/g to 200 ng/g with the correlation of coefficient (r2) > 0.990 for all the 6 pesticides. The method was found to be precise with a method LOQ (Limit of Quantification) concentration level of 10 ng/g, with % RSD (Relative standard deviation) for 6 replicates as less than 15% for all the six compounds. Recovery studies in dried chilli shows that method is accurate at all the three recovery levels i.e. 10 ng/g, 20 ng/g and 50 ng/g with % RSD (n-6) < 15 for all the six pesticides. Mean recovery control charts were plotted for recovery data, as a performance based quality assessment tool. Validated method was also applied to 8 popular market brands and 6 loose unbranded samples collected from the local market of India to check pesticide load in them