Validation of QuEChERS Method Coupled with LCMS/MS for Determination of Thiamethoxam and ts Metabolites in Wheat and Soil

• Published in: Journal of AOAC International 2021-04
• Main Authors: Rasool, Rozy, Kang, Balpreet Kaur, Mandal, Kousik
• Format: Article
• Language: English
• ISSN: 1944-7922

Thiamethoxam, a neonicotinoid insecticide, has been widely accepted for the control of sucking and certain chewing pests. Through different routes viz., wind drift, leaching and surface runoff, it can reach non-target areas which includes humans as well. So, the fate of thiamethoxam in food grains and soil is of prime importance, entailing that pesticide use is subject to steady observation. To validate QuEChERS method for detection of thiamethoxam and its metabolites in wheat leaves, grain, straw, and soil using LCMS/MS. The QuEChERS method allows sample extraction by acetonitrile followed by clean up with primary secondary amine sorbent, magnesium sulphate and graphitized carbon black. The method was validated in terms of selectivity, linearity, LOD, LOQ, matrix match, accuracy, and precision. The estimation of residues was done by LCMS/MS. Results: Recovery of thiamethoxam and its metabolites in wheat and soil samples was in the range of 81.22 to 98.14%. LOQ for thiamethoxam and its metabolites was 0.01 mg/kg. The matrix effect values were in the acceptable range of -20 to + 20%. The method allows simple and fast extraction of thiamethoxam and its metabolites from wheat leaves, grain, straw, and soil. It could be helpful in evaluation of regulatory and food safety decisions regarding use of neonicotinoids. Highlights: The method was validated according to the SANTE/12682/2019 guidelines. An accurate, simple, and sensitive analytical method was validated for thiamethoxam and its metabolites.