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During the period 1986-1988 a total of 602 samples of animal products were analysed for organochlorine and organophosphorus pesticides and industrial organic pollutants. Samples of abdominal fat were collected from avian, bovine, caprine, lupine, ovine and porcine species together with hen eggs. The following six compounds were identified in animal tissues: DDE, dieldrin, lindane, PCB, pentachlorophenol and tetrachlorophenol. Pentachlorophenol was the most frequently found contaminant, being identified in 35% of samples, and DDE was the second in 21%. All other contaminants were present in less than 10% of samples. The residues of all six compounds detected were added to give a combined residue. Forty-three per cent of samples had non-detectable residues. A further 31% had combined residues adding to less than 0.01 mg/kg. The highest combined residues ranged between 0.1 and 1.0 mg/kg and were present in 2.8% of samples. One egg sample had a residue of 0.16 mg/kg that exceeded the 0.1 mg/kg maximum residue limit for pentachlorophenol. Residues of chlordane and its metabolites, heptachlor and its epoxide, endosulphan and its sulphate metabolite, dicofol, HCB and mirex were below their detection limits in all samples and no residues of the organophosphorus insecticide listed as applied to livestock were found in meat, fat or egg tissues.

Abdominal fats were collected from 8-week old broilers slaughtered at provincially inspected abattoirs across Ontario between 1969 and 1982. Domestically produced hen eggs were collected from either egg grading stations or producers over the same period. Composite samples were analyzed for organochlorine insecticides and industrial chemicals. Between 1979 and 1982, organophosphorus insecticides were routinely included in these analyses. Sigma DDT and PCB residues declined rapidly between 1969 and 1982 in extractable lipids of both abdominal and egg fats, while dieldrin declined less markedly over the same period. Declines in residues followed first order logarithmic regression equations. Chlordane and heptachlor epoxide were rarely observed above the detection limit of 1 microgram/kg in egg fat; however, the incidence of these residues in abdominal fat increased after 1973 following the removal of aldrin, dieldrin, and heptachlor in 1969 and the subsequent increased use of chlordane for soil insect control until 1977. Lindane residues were rarely observed above the detection limit. In 1979, when the detection limit was reduced, both alpha-BHC and lindane were identified, but at levels below 1 microgram/kg. Endosulfan, methoxychlor, and fenthion were identified on one or 2 occasions over the 13-year period.