Naturally Occurring Toxicants in Foods

ivilized man is capable of controlling many C aspects of his environment and thereby eliminating or at least diminishing some of the potential threats to his life and health. The absolute necessity of nutrition for continuance of life points to his foods as critical substances that must be maintained free from significant levels of toxicants. Fortunately man is less frequently the target of food intoxications than are domestic animals simply because in most societies greater selective care is given to human foods. Man consumes many of the same basic dietary items as animals, however, and on rare occasions may ingest toxicants contained in the meat or milk of livestock that were allowed to eat toxin-laden feed or to graze toxic plants. So-called “natural foods” consist of “chemicals” any one of which can be deleterious to health if ingested in excessive quantities. Some of the more potent toxic metabolites of animals and plants used as food are formed during their normal course of metabolism and growth. Others, such as toxic phytoalexins, may be acquired under conditions including microbial infection, mechanical and chemical injury, and insect parasitism. A third group can be attrib-