Abstract
The effects of water-soaking pre-treatment of powdered dry cereal on pesticide residue analysis in brown rice and wheat were examined. The recovery of several pesticide residues found in cereal by acetone extraction without water-soaking was as low as 6–68% of recovery after water-soaking pre-treatment for 30 min. The optimal soaking time in water was 15 to 30 min for the powdered cereal samples. The relative recovery of spiked pesticides and residual pesticides was not always parallel between the two extraction conditions, i.e., acetone extraction with and without water-soaking pre-treatment. Pre-treatment produced higher measured values in many cases, but also resulted in lower values for some pesticides like malathion and diazinon. Soaking dry samples in water for 15–30 min as pre-treatment will give good residual pesticide extraction. © Pesticide Science Society of Japan