Degradation of mancozeb and ethylenethiourea in apples due to postharvest treatments and processing

Apples sprayed with product label rates of mancozeb in the orchard were used to determine the effectiveness of various wash treatments on the removal of the mancozeb and ethylenethiourea (ETU) on and in fresh and processed apples. Reduction in residual mancozeb and ETU was significantly (p < 0.05) influenced by the effect of various wash treatments as compared to the unwashed samples. There was significantly higher residue in the water-washed apples than apples processed with chlorine, chlorine dioxide, hydrogen peroxyacetic acid, and ozone washes. We found that certain procedures, such as peeling or steaming, play an important role in reducing pesticide residue levels in processed apples.