Application of the AOAC multi-residue method to determination of synthetic pyrethroid residues in celery and animal products.

A procedure based on current multi-residue methodology is described for the determination of synthetic pyrethroid residues in vegetable and animal tissues. Permethrin, cypermethrin, and fenvalerate are extracted from celery, egg yolk, beef muscle, and milk with acetonitrile, partitioned into hexane, and cleaned up on Florisil for quantitation by electron capture gas chromatography. Recoveries of the 3 pyrethroids averaged 94-103% from celery and 82-97% from animal products. Minimum detectable levels of less than 5 ng/g are readily attainable. The method also allows for the simultaneous extraction and cleanup of the organochlorine hydrocarbon insecticides which have been routinely analyzed in the past.