Abstract: | Modified versions of previously published procedures for the extraction and clean-up of some organophosphorus insecticide residues in fruits and vegetables are described, and their usefulness in combination with selected thin-layer chromatographic procedures is experimentally assessed for several pesticides in apples, oranges, tomatoes, carrots and peas. A simple extraction procedure for insecticidal carbamates is similarly evaluated for carbaryl and propoxur residues in apples, carrots and peas. Semi-quantitative estimation, by visual comparison with standards, is shown to be possible in many cases at residue levels as low as 0.4 mg kg?1, and the combined procedures should be useful in the screening of fruits or vegetables for compliance with maximum residue limits. |