Pesticide residue analysis of edible insects: method development and market survey in Japan

The increasing global demand for protein highlights the importance of sustainable alternatives to conventional livestock production. Edible insects offer high nutritional value and reduced environmental impact, although contamination risks from rearing substrates remain a critical concern. To accurately determine pesticide residues in edible insects, we developed and validated a sensitive multi-residue quantification method. This method combines optimised sample preparation-including acetone-based extraction, defatting with a diatomaceous earth cartridge, and solid-phase extraction clean-up-with LC-MS/MS and GC-MS/MS analyses. Method validation with European house cricket (Acheta domesticus) samples spiked at 0.005 and 0.01 mg/kg showed satisfactory performance, with trueness within 70%-120%, precision ≤25% intra-day and ≤30% inter-day, and limits of quantification (LOQs) of 0.005 mg/kg for 268 of 285 target compounds using matrix-matched calibration and for 241 of 285 compounds using solvent-based calibration. Application of the method to 50 commercial edible insect products in Japan revealed quantifiable pesticide residues in nine samples, with 20 pesticides detected above the LOQs and several exceeding 0.01 mg/kg in dried products. The developed method enables accurate determination of pesticide residues in edible insects and provides insights into their contamination status. Future work will focus on developing more streamlined procedures for routine monitoring.