Introduction

Classes and uses of pesticides

Legal framework

Approval Levels

Scientific information in the regulatory process.

Risk Management Process

Constitution and function of the various organisations

Management of pesticides in the future.

Dietary Intake....

One of the ways by which a pesticide might cause harm to humans is through its presence as a residue in food. A particular concern is the potential for residues in the food derived directly from any crops to which it is applied, but residues may also occur in other foods by indirect routes. For example, they might arise in the meat of animals that have been fed on a treated crop. Furthermore, the particular product that is being evaluated may not be the only source of the pesticide in the diet. The same chemical may also be a constituent of other products that are already on the market in the UK or in other countries from which we import food. In assessing the risks from residues of a pesticide in foods, therefore, it is necessary to identify and take account of all foodstuffs in which significant residues might occur, including those resulting from the use of other products that contain the same active substance.

To check whether the proposed use of a pesticide might cause unacceptable longterm dietary exposures, an estimate is made of the maximum intake that an individual would be expected to incur over a prolonged period. This is based on the distribution of measured residues of the pesticide in foods derived (directly or indirectly) from treated crops, and data on the national patterns of consumption for different foods from official surveys, as now commissioned by the Food Standards Agency.

The long-term dietary exposure to a pesticide, calculated in this way, is compared with the acceptable daily intake (ADI). If the ADI is exceeded, the proposed use of the pesticide will not be acceptable. The effect of any over-estimation of potential dietary intakes is to err on the side of safety.

Separate calculations are carried out for dietary exposures in infants and children, and other consumer groups, to check that they all will be acceptable. Also, if the pesticide has toxic effects that could arise from a single dose, an estimate is made of the maximum dietary exposure that could occur in a single day or from a large portion of that food and this is compared with the acute reference dose (ARfD). If the ARfD is exceeded, again the proposed use will be unacceptable.

Finally, if the use of a pesticide produces significant concentrations of toxic metabolites in food (i.e. substances formed by its chemical degradation in plants or animals), the acceptability of exposure to each of these metabolites is also assessed.