The potential toxicity of chemicals used in food technology.

Introduction Many of the substances used as food additives possess no outstanding toxic property; others which may be used as adjuncts in processing may be toxic but are present in the food only in very small quantities. The study of non-toxic substances resolves itself into the problem of trying to prove a negative. An experimental investigation of the toxicity of many of the chemicals used in food technology may end at the point where one is left to consider the possibility that some toxic property hitherto unsuspected might eventually reveal itself among the human population exposed to the exhibition of the substance in some popular foodstuff. The question thus arises of the scientific adequacy of the laboratory methods now used to elicit the inherent toxicity of substances. The situation created by the presence in food of traces of materials known to be toxic in greater concentrations is slightly different. The problem here is whether a material endowed with specific toxic properties when given at a certain dose level can produce unsuspected chronic toxic effects if ingested over long periods in amounts not demonstrably toxic in the original way. This paper does not attempt a survey of the toxic properties of the chemicals commonly used in food technology or to criticize current methods of toxicity testing. The first task would require a book; the second has been done on two previous occasions (Barnes & Denz, 1954; Barnes, 1955). In the hope of stimulating discussion the general problem will be briefly described and illustrated.