Abstract
A chromatographic method is described for the extraction and clean-up of organochlorine pesticide residues in animal fats and oils, fatty animal tissues, vegetable oils, dairy products and eggs. The sample mixed with Celite is packed into a small column and the pesticide residues eluted with a little dimethyl sulphoxide. The eluate is then adsorbed on Florisil and the residues recovered from the dimethyl sulphoxide by elution with hexane. The amount of material passing through the clean-up is usually less than 0·01 per cent. of the sample.