QuEChERS methodology and Gas Chromatography-mass spectrometry for detection of 345 pesticide residues in Egyptian poultry feed: a comprehensive study

Animal feed significantly influences the content and quality of animal products consumed by humans and plays a crucial role in the food chain. To simultaneously analyze 345 pesticide residues in poultry feed, a modified Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method was developed, utilizing gas chromatography-tandem mass spectrometry (GC-MS/MS). Validation studies were conducted with spiked pesticide standards, and commercial poultry feed samples were analyzed. The linearity of the QuEChERS method was evaluated, showing high coefficients of determination (<i>R</i>² ≥0.995) for all analytes. The method demonstrated excellent linearity (<i>R</i>² ≥0.995), recovery rates (86.8-109.2%), and precision (RSD ≤14.8%), meeting SANTE criteria. Limits of detection (LOD) ranged from 0.5 to 5 ng/kg and limits of quantification (LOQ) from 1 to 10 ng/kg, enhancing the method's reliability. Analysis of the poultry feed revealed that 15 out of the 345 pesticide residues were detected in the samples, with concentrations ranging from 2.1 to 120 µg/kg. The detected pesticide categories included insecticides, fungicides, plant growth regulators, and herbicides, in that order. In conclusion, the QuEChERS method combined with the GC-MS/MS approach provides a reliable technique for the multi-residue analysis of pesticides in complex feed matrices.