ABSTRACT
Chlorinated dibenzo-p-dioxins can arise and enter the environment in a variety of ways: as by-products of chemical syntheses, as contaminants in commercial chlorophenol-based products, as products of combustion, and as constituents of waste disposal materials. To determine the presence of dioxin residues in food, several other food commodities as well as fish have been analyzed for residues of 2,3,7,8-TCDD, and a number of foods of animal origin have been analyzed for residues of the higher-chlorinated dioxins present in PCP, hexa-, hepta-, and octachlorodibenzo-p-dioxin. Residues of dioxins have also been reported in birds and fish from the Great Lakes region and in food-grade gelatin and beef fat. Test portions were cleaned up and analyzed for 2,3,7,8-TCDD residues according to the isomer-specific method described by Niemann et al. Preliminary extraction and cleanup involved a basic digestion, hexane extraction, and sulfuric acid wash or a modification of the sulfuric acid column cleanup described by L. L. Lamparski and T. J. Nestrick.
