Comparative Toxicology

Abstract

The usefulness of animal experiments to predict drug toxicity in man is not valued equally by all scientists engaged in evaluating the potential risk of new chemicals. There are those who strongly believe in the essential sameness of living organisms including man, this conviction culminating in such statements as “DNA is DNA”. There are others who, deep in their hearts, feel that animal experiments are a waste of time and that only the crucial test in man will truly predict what a drug will do in man. These extreme views are so untenable that they are rarely voiced in the open anymore. But one does not have to be a toxicological radical to believe that species differences constitute the most serious limiting factor in experimental drug toxicology. However, one should also not behave like a toxicological chauvinist and use the species difference argument only to belittle a harmful effect of one’s drug; it matters just as much for negative findings! Toxicological observations in animal model systems are to be looked at as pieces of evidence, scientific facts which by themselves are neither good nor bad. To be fully understood, they must be related to the clinical situation in which the drug will be used. Comparative toxicology provides the necessary conversion tables which help to put safety testing into proper perspective.