title: Risk assessment of ochratoxin A residues in food.
abstract: Ochratoxin A is a mycotoxin that has been found to occur in foods of plant origin, in edible animal tissues and in human sera and tissues. The ability of ochratoxin A to move up the food chain is associated with its long half-life in certain edible animal species. In this presentation, approaches for the evaluation of the health risks due to the presence of ochratoxin A in food products are described. The major target for ochratoxin A toxicity in all mammalian species tested is the kidney, and endemic nephropathies affecting livestock as well as humans have been attributed to ochratoxin A. Ochratoxin A is also teratogenic, and in the fetus the major target is the developing central nervous system. Recent studies have provided 'clear evidence' for the carcinogenicity of ochratoxin A in two rodent species. It was found to be non-mutagenic in various microbial and mammalian gene mutation assays, but weak genotoxic activity to mammalian cells was noted. In addition, ochratoxin A was found to suppress immune function. On the basis of a carcinogenicity study with ochratoxin A in rats, reported from the National Toxicology Program in the USA, the estimated tolerable daily intake of ochratoxin A in humans ranges from 1.5 to 5.7 ng/kg bw per day, depending on the method of extrapolation used. The worst-case estimate for daily exposure to ochratoxin A from the consumption of pork-based food products and cereal foods for young Canadian children, the highest consumption group on a body weight basis, is probably less than 1.5 ng/kg body weight per day (mean of eaters). In view of the toxic properties of ochratoxin A, it is recommended that exposure to this toxin be kept to a minimum.
authors.affiliation: Toxicological Evaluation Division, Health and Welfare Canada, Tunney's Pasture, Ottawa.
authors.forename: T
authors.initials: T
authors.lastname: Kuiper-Goodman
mesh_terms: D000014:Abnormalities, Drug-Induced / Q000209:etiology; D000821:Animal Feed; D000818:Animals; D000829:Animals, Domestic / Q000378:metabolism; D001449:Balkan Nephropathy / Q000139:chemically induced; D015197:Carcinogenicity Tests; D002490:Central Nervous System / Q000002:abnormalities / Q000196:embryology; D004781:Environmental Exposure; D005506:Food Contamination / Q000032:analysis*; D006207:Half-Life; D006801:Humans; D007674:Kidney Diseases / Q000139:chemically induced / Q000662:veterinary; D007680:Kidney Neoplasms / Q000139:chemically induced; D008452:Maximum Allowable Concentration; D008460:Meat / Q000032:analysis; D051379:Mice; D015651:Mycotoxicosis / Q000209:etiology / Q000662:veterinary; D009793:Ochratoxins / Q000009:adverse effects / Q000032:analysis / Q000493:pharmacokinetics / Q000633:toxicity*; D051381:Rats; D012306:Risk; D013552:Swine / Q000097:blood; D013553:Swine Diseases / Q000139:chemically induced
chemical_list: D009793:Ochratoxins; C025589:ochratoxin A