DISTRIBUTION OF PESTICIDE-RESIDUES IN VEGETABLES AND FRUITS AND REMOVAL BY WASHING

Marketed vegetables and fruits contaminated by organophosphorus, organochlorine, or carbamate pesticides were cut into several regions (fruit stalk, pericarp, fruit receptacle, tissue around the stalk cavity, etc.) and the concentration of the pesticide residues in each region was assayed. In fruits and fruit-type vegetables, the concentration of the pesticide residue was higher in the fruit stalk and near the epidermis (exocarp and fruit receptacle) than in the sarcocarp or pericarp. In leaf vegetables, the concentration of the pesticide residue was higher in the outer leaves than in the inner ones. There was no pesticide contamination of the inner leaves of Chinese cabbages with a well-formed head. Dieldrin and heptachlor epoxide were detected in pumpkins and cucumbers, although their use in agriculture has been prohibited in Japan for about 20 years. The removal rates of pesticide residues by washing with water or 0.1% liquid detergent for kitchen use were from 8 to 52% and from 19 to 67%, respectively. Removal of the fruit stalk, exocarp, and tissue around stalk cavity of fruits and fruit-type vegetables and washing of leaves with water or dilute detergent solution for kitchen use were necessary to decrease the intake of pesticide residues from vegetables and fruit.