Validation of an HPLC-MS/MS method for the quantification of pesticide residues in Rice and assessment of the washing effect

A method was validated to determine 121 pesticide residues (carbamates, organophosphates, organochlorines, and pyrethroids) in rice samples, following the guidance document SANTE/11312/2021v2. QuEChERS method was selected for pesticide extraction, and the extract was analyzed by HPLC-MS/MS. The methodology demonstrated precision and accuracy, with recovery rates ranging from 70 % to 119 %. Additionally, the study aimed to assess the effects of washing on residue levels of 121 pesticides in contaminated long-grain rice samples. Subsequently, the rice underwent washing, and the pesticide residues were determined in the samples to evaluate the retention factor. The results suggest that the washing process can enhance the elimination of pesticide residues in rice, around 40 % of pesticides have reduced between 40 and 60 %, and 10 % of pesticides reduced by more than 60 %. This research contributes with valuable insights for improving food safety measures in the context of pesticide-contaminated cereals. Chemical compounds: (Azoxystrobin) PubChem CID: 3034285 (Cadusafos) PubChem CID: 91752 (Diazinon) PubChem CID: 3017 (Epoxiconazole) PubChem CID: 107901 (Fenamidone) PubChem CID: 10403199 (Fenpropimorph) PubChem CID: 93365 (Mepanipyrim) PubChem CID: 86296 (Pirimiphos-methyl) PubChem CID: 34526 (Propiconazole) PubChem CID: 43234 (Spiroxamine) PubChem CID: 86160