Determination of Cypermethrin, Chlorpyrifos and Diazinon Residues in Tomato and Reduction of Cypermethrin Residues in Tomato Using Rice Bran

The present study was an attempt to address the health hazard which posed by the ingestation of pesticide residues contained in tomato. Fourteen tomato samples were randomly selected from different shops of local markets of Savar Upazila, Bangladesh and analyzed to identify the level of widely applied cypermethrin, chlorpyrifos and diazinon residues by using high performance liquid chromatography (HPLC) technique. It was found that out of 14 samples, five were found contaminated with cypermethrin and one with chlorpyrifos, but none residue of diazinon was detected in any of the tested samples. Only 7% of the samples were found contaminated with cypermethrin insecticide residue which was above the maximu m residue level (MRL) adopted by the FAO/WHO Codex Alimentarius Commission (CAC), although cypermethrin (0.065 ± 0.07mg/kg) and chlorpyrifos (0.024 ± 0.041mg/kg) residues were detected in samples. Rice bran rubbing, a cheap decontamination technique, was used to treat applied cypermethrin residues. 0.45 mg/kg of cypermethrin spiked tomato samples were rubbed by rice bran paste for 5, 10 and 15min. Two experiments were conducted for assessing the efficiency of the adsorbent. Rubbing with rice bran paste for 10min, removed 97.73% and 97.4% in both trails, and whereas cypermethrin residue was not detected in tomato samples treated for 15 min. The removal efficiency was 97.56 ± 0.22% with the ads orbent rice bran rubbing for 10min. The result showed that cypermethrin residues of tomato sample could easily be decontaminated through absorption of rice bran.