The concept of the acceptable daily intake: an historical review

In the first section the sequence of events is outlined which leads to the author's proposal to consider the concept of acceptable daily intake (ADI) for pesticide residues. He developed his theory referring to specific aspects during meetings with experts on the toxicological evaluation of chemical agents which become introduced into foodstuffs intentionally or unintentionally. These meetings were organized periodically by the European Council or Joint FAO/WHO Expert Committees on food additives (JECFA) or pesticide residues (JMPR). The general principles of the ADI evaluation are briefly described as being based on the determination (after extended absorption) of a no-effect dose level in an appropriate animal species; followed by the application, for the extrapolation of the results in animals to humans, of safety factors taking into account the interspecies sensitivity variations and individual sensitivity variations in the groups of essentially heterogeneous human consumers. It is pointed out that the ADI value, which depends on a series of factors, is not a constant, but a guide serving to calculate the admissible limits of diverse chemical agents incorporated in foodstuffs. It must take into account the usual normalities between medium terms of consumption varying a lot with the countries and the various consumer groups. It is clearly noted that, because of the fluctuations in the type and the quantities of absorbed diets, the ADI is in reality an integrated value with regard to the time, a notion that is often forgotten. Other ideas are developed, in particular on the adoption of a temporary ADI and on the concept of a non-specified ADI.