Mixtures of pesticides timeline

The Agency's action plan puts into place a programme that investigates the assessment of any possible risk from the combined effect of the different pesticides in food, implementing the recommendations of the COT. The plan includes carrying out more toxicological research into any possible combination effect and changes to the system for approving pesticides.

The Agency produced the draft action plan on the risk assessment of mixtures of pesticides to take forward recommendations in the COT report, working with the Pesticides Safety Directorate (PSD), the Veterinary Medicines Directorate (VMD), the Department for the Environment, Food and Rural Affairs (Defra), the Department of Health (DH) and the Health and Safety Executive (HSE).

The draft action plan sets out the COT report's recommendations and a proposed two-stage course of action.

In stage one, the Agency will carry out COT's recommendations and work towards:

• taking account of groups of substances with 'common toxicological mechanisms' (chemicals that affect the same part or process in the body)
• looking at how to do exposure assessments that include different sources, such as food, air and water, including exposure in the home
• investigating how to put these two processes together to conduct a risk assessment for mixtures

In stage two, the Agency will use the scientific evidence gathered in stage one to argue for changes to EC legislation and international standards, to take account of possible combination effects. The UK is bound by EC regulatory frameworks for agricultural pesticides, biocides and veterinary medicines, which means that it can't unilaterally change the authorisation process of these substances.

Following a 20-month assessment by WiGRAMP and the draft report produced in February 2002, the final COT report on the Risk Assessment of Mixtures of Pesticides and Similar Substances was published in October 2002.

The Committee concluded that the risk to people's health from mixtures of residues is likely to be small. It said that children and pregnant or breastfeeding women are unlikely to be more affected by the 'cocktail effect' than most other people. But the report also said that there is only limited evidence in this area and it might not be easy to predict how some chemicals would interact.

The report recommended:

• changing the approvals system, so the bodies responsible for authorising pesticides and veterinary medicines in the UK would be required to consider all sources of exposure
• establishing a scientific and systematic framework to evaluate when it's appropriate to carry out combined risk assessments of exposure to more than one pesticide and/or veterinary medicine
• carrying out further research on possible human exposure to mixtures of chemicals present in pesticides and veterinary medicines

The Food Standards Agency asked WiGRAMP to conduct an assessment of existing scientific information and data, and consider any implications for the risk assessment of pesticides and veterinary medicines used in agriculture. The following issues are covered in the draft report:

• stakeholder concerns and particular types of pesticides and veterinary medicines that cause concern
• current regulatory systems for the approval of pesticides and the marketing authorisation of veterinary medicines in the UK and the European Union (EU)
• licensing of human pharmaceuticals and the regulation of animals feed additives
• exposure assessment
• toxicology of mixtures
• risk assessment

The Working Group for the Risk Assessment of Mixtures of Pesticides and Veterinary Medicines (WiGRAMP) was established by the Committee on the Toxicity of Chemicals in Food, Consumer Products and the Environment (COT) in December 2000. The Food Standards Agency asked COT to establish the Working Group because of public concern about mixtures of pesticides.

The Working Group, which was chaired by Professor Frank Woods, included members from scientific, consumer, pesticide-surveillance and veterinary backgrounds. The Group's main aims were to:

• assess the potential effect on human health of multiple residues of pesticides and veterinary medicines in food
• consider the potential impact on human health of repeated exposure to pesticides and veterinary medicines by different routes
• formulate advice on the procedures used to assess the risk from individual pesticides and veterinary medicines for the appropriate regulatory agencies

This report highlighted the existence of multiple residues in some commonly consumed foods. Although the report didn't raise concerns about a health risk from mixtures of pesticides, Agency research suggested that members of the public were concerned about a possible 'cocktail effect', particularly in relation to children.