In Vivo Investigation of Dietary Exposure to 5

In Vivo Investigation of Dietary Exposure to 5 Pesticides

1 Introduction

We are all daily exposed to a number of pesticides from the food we eat and the water we drink. In food anlysed by The Danish Veterinary and Food Administration pesticide residues are often found. In 2001 pesticide recidues were found in aproximately 30% of the test samples taken from fruit produced in Denmark and in aproximately 70% of test samples taken from fruit produced outside Denmark (8). Pesticide residues are also found in vegetables and food crops but at lower levels (8).

The possible adverse health effects of a pesticide have traditionally been evaluated on the basis of the individual pesticide. However, even though we often are exposed to more than one pesticide through the food, the knowlegde of adverse health effects of combination of pesticides is only limited. It has been known for many years that pharmaceutical drugs can interact and therefore it is likely that other compounds like pesticides also interact. However, the levels for intake of pesticide residues is much lower than the therapeutical levels of a drug and interaction occuring at high dose levels may not be representative for low dose level exposure (11;16).

Various approaches have been suggested for risk assessment of mixtures of chemicals (14;20;21), but there are no internationally accepted procedures. It has been suggested that the most practical approach for evaluation of combined effects would be the assumption of an additive effect, since most compounds in combination have not more than an additive effect (14). The Danish Veterinary and Food Administration uses as a first cut-of an approach of summing all pesticide residues and compare the intake based on the acceptable daily intake (ADI) for the most toxic pesticide involved for the risk assessment (25). If the summarized ADI for all the pesticides exceeds the most toxic compound’s ADI a Hazard-Index is calculated (8). A Hazard-Index is calculated as the sum of the theoretical intake of the individual pesticide in the food item in relation to the individual pesticides ADI (8).

The overall objectives of the animal experiments presented in this report was to contribute to the limited knowledge of risk assesments for intake of combination of pesticides.