Evaluation of ozone treatment as a decontamination technique for reducing pesticide residues in vegetables using Liquid Chromatography–Tandem Mass Spectrometry and Gas Chromatography–Tandem Mass Spectrometry analysis

The accumulation of pesticide residues in fresh vegetables is a significant food safety challenge. This study evaluated ozone (O₃) gas as a non-chemical decontamination technique for reducing residues of four prevalent pesticides the neonicotinoids imidacloprid and acetamiprid, the organophosphate chlorpyrifos, and the pyrethroid cypermethrin on okra, cabbage, and cauliflower. Artificially contaminated samples were exposed to ~ 3.2 ppm ozone for 20 min. Residue extraction utilized the QuEChERS method, followed by quantification via LC-MS/MS for neonicotinoids and GC-MS/MS for chlorpyrifos and cypermethrin, with calibration curves confirming excellent linearity (R² ≥ 0.999). Ozone treatment significantly reduced all pesticide residues. Maximum reduction efficiencies reached 37.0% for acetamiprid, 35.4% for imidacloprid, 33.3% for chlorpyrifos, and 31.9% for cypermethrin. Higher removal in cabbage and cauliflower than okra correlated with surface morphology favoring ozone interaction. These findings support ozone as a broad-spectrum, eco-friendly post-harvest intervention.