Pesticide residues in milk and fish samples collected from upper Egypt.

In Egypt, buffalo milk is much preferred by consumers over cow's milk, while small catfish and bolti fish are common in the diet of farmers. Samples of buffalo milk, catfish, and bolti fish collected from Beni-Suef Governorate (Upper Egypt) were analyzed for organochlorines and polychlorinated biphenyls. The results obtained by gas chromatography and confirmed by thin-layer chromatographic techniques revealed high amounts of organochlorines in milk; residues were lower but occurred more frequently in fish samples. Pesticide contaminants found most often were HCH isomers including lindane, DDT complex, aldrin and dieldrin, heptachlor and heptachlor epoxide, hexachlorobenzene, and oxychlordane. Polychlorinated biphenyls were not detected in any of the analyzed samples.