Methods to Reduce Dietary Intake
Of Pesticide Residues in Apples
Machelle Jaruzel
School of Natural Sciences
Lake Superior State University
Sault Ste. Marie, Michigan
49783
Abstract: Dietary intake of certain fruits and vegetables may be a significant pathway for exposure to contaminants such as residual pesticides. Apples have been found to have high pesticide loads. Single samples of apples have been found to contain as many as seven different pesticides. The objective of this study was to explore thin-layer chromatography as a semi-quantitative method for determining if organophosphorous pesticides were present on apple samples Three washing methods were then tested for their effectiveness removing residual pesticides in apple samples. The target pesticides included malathion and methyl parathion, which are known to affect the nervous system. Thin-layer chromatography was performed on Alumina, incorporating silver nitrate as a sensitive and selective visualizing reagent. The untreated apples had no residuals of malathion or methyl parathion, which could be detected to the detection limits of the testing procedure. All three of the washing methods appeared to be effective in reducing pesticide residues in the samples.