The determination of residues of dichlorvos in crops and tissues

Abstract

An analytical method for determining residues of dichlorvos with a limit of determination of 0·01 p.p.m. is described. It is intended for use by those laboratories which carry out residue analysis for regulatory purposes, with an emphasis on speed, specificity and sensitivity.

Residues of dichlorvos are extracted with either dichloromethane or ethyl acetate, the extracts are cleaned up by steam distillation and the concentration of insecticide is determined by gas-liquid chromatography in which one of three selective detectors, the flame-photometric, “thermionic” or electron-capture detector, is used.