Effects of various rinsing conditions on residues of chlorpyrifos ethyl, acetamiprid and penconazole in grapes

Abstract

Effects of various rinsing conditions were investigated to remove residues of three pesticides including chlorpyrifos ethyl, acetamiprid and penconazole in grapes. The rinsing conditions included five different temperatures of rinsing water, three different fruit-to-water ratios and three different dipping times. The residual levels of all three pesticides decreased with decreasing the rinsing water temperature while in most cases, 10, 20 and 30 °C produced lower pesticide residue values when compared to 40 and 50 °C within each of combined treatments. In addition, 4 minutes of dipping time was not as effective as 2 and 3 minutes dipping times to eliminate chlorpyrifos ethyl residue from grape samples at all temperatures. Degradation kinetics of chlorpyrifos ethyl, acetamiprid and penconazole was also studied in grape samples at 4^oC during 90 hours storage and percentages of pesticide residues were determined at the end of the storage period as 18.56, 23.89 and 9.17 % respectively.