Validation of QuEChERS Method for Estimation of Imidacloprid and its Metabolites in Cotton Flower, Pollen, Nectariferous Tissue, and Honey

Background: Exposure of Apis mellifera to neonicotinoid insecticides is one of the factors attributed to the recent decline in A. mellifera populations resulting in economic and ecological losses due to loss of pollination services. Honeybees can get exposed to neonicotinoids like imidacloprid directly in the field at the time of application as well as during consumption of pollen and nectar from treated plants. In addition, some metabolites of imidacloprid are more toxic than the parent compound. So, the fate of imidacloprid and its metabolites in commodities to which honeybees get exposed needs to be overhauled. Objective: To validate QuEChERS method for estimation of imidacloprid and its metabolites in cotton flower, pollen, nectariferous tissue, and honey using HPLC. Methods: The QuEChERS method was validated in terms of selectivity, linearity, LOD, LOQ matrix match, accuracy, and precision. The estimation of residues was done by HPLC. Results: Recoveries of imidacloprid and its metabolites for cotton flowers, nectariferous tissue, pollen and honey samples were in the range of 80.42-99. 83%. LOQ for imidacloprid and its metabolites was 0.01 mu g/g. Acceptable precision (RSD < 20%) was obtained. Conclusion: The method allows simple and fast extraction of imidacloprid and its metabolites from cotton flower, pollen, nectariferous tissue, and honey.