Reduction of pesticide residues from tomatoes by low intensity electrical current and ultrasound applications.

In this study, effects of low intensity electrical current (EC) and ultrasound (US) treatments on the reduction of some important pesticides (captan, thiamethoxam and metalaxyl) residues in tomato samples were investigated. Three different currents (200, 800 and 1400mA) of EC were applied at various time intervals (2, 4, 6, 8 and 10min). Two kinds of US treatments including ultrasonic bath (UB) at 40kHz and ultrasonic probe (UP) at 24kHz were tested for the determination of US effectiveness. In addition, synergistic effects of US on EC treatments were evaluated. The most effective conditions for reduction of captan, thiamethoxam and metalaxyl residues were 1400mA+40kHz, 800mA+24kHz and 1400mA+24kHz, respectively. The residues of captan, thiamethoxam and metalaxyl were reduced in the order of 94.24%, 69.80% and 95.06% by using these combinations. EC and US strategies can be considered as effective treatments in industrial scale in order to remove the pesticide residues from vegetables.