Risk assessment of mixtures of pesticides. Current approaches and future strategies.

The risk assessment of pesticide residues in food is based on toxicological evaluation of the single compounds and no internationally accepted procedure exists for evaluation of cumulative exposure to multiple residues of pesticides in crops, except for a few groups of pesticides sharing a group ADI. However, several attempts have been suggested during the last decade. This paper gives an overview of the various approaches. It is of paramount importance to consider whether there will be either no interaction or interaction between the compounds in the mixture. When there are no interactions several approaches are available for the risk assessment of mixtures of pesticides. However, no single simple approach is available to judge upon potential interactions at the low doses that humans are exposed to from pesticide residues in food. In these cases, PBTK models could be useful as tools to assess combined tissue doses and to help predict potential interactions including thresholds for such effects. This would improve the quality of the risk assessment.