NATURAL CARCINOGENS AND DIOXIN

Toxicology studies of synthetic chemicals at high doses must be viewed in the context of the world of natural chemicals, which make up the vast bulk of the chemicals to which humans are exposed. In tests at near toxic doses (e.g., the maximum tolerated dose), one-half of all chemicals, whether synthetic or natural, are carcinogens; one-third are teratogens, and about half are clastogens. Natural and synthetic chemicals are similar in their toxicology, and at the low doses of most human exposures where cell-killing does not occur, the hazards may be much lower than are commonly assumed and often will be zero. It is shown that the comparative hazards of dioxin at the levels that are causing concern appear insignificant.