[Analytical method for residues of methylcarbamate insecticides in plant foods]

An analytical procedure is described for identification and quantitative determination of 15 methylcarbamate insecticides and 4 metabolites in fruits and vegetables. Clean-up includes ethyl acetate extraction, isolation of residues by a Sep-pak C18 disposable cartridge, elution with acetonitrile-water 1 + 1, and partitioning into dichloromethane. GLC is performed by using a well deactivated non-polar capillary column (e.g. SE-52, DB-1), splitless injection, and nitrogen-selective thermionic detection. Derivatisation with 2,4-dinitrofluorobenzene is suitable for confirmation. The limits of determination according to DFG criteria were in most cases as low as 0.005-0.01 mg/kg.