Defra - Department for Environment, Food and Rural Affairs.

Science Search

Science and Research Projects

Return to Science Search homepage   Return to Project List

Improving assessments of the risk to birds from pesticide contaminated drinking water - PS2327

Description
Annex VI to EU Directive 91/414 requires that plant protection products should not be authorised for sale if they pose unacceptable risks to birds and other non-target terrestrial vertebrates. Following pesticide application, birds may be exposed to pesticides via drinking water. Possible scenarios include:

· Direct ingestion of spray liquid from plants after spraying (e.g. in axils/whorls).
· Drinking from oversprayed puddles on field.
· Drinking from spray drift contaminated puddles/water bodies.
· Drinking from run-off contaminated puddles/water bodies.

While exposure via these routes is possible there is a need to critically assess the likelihood of these occurring under current UK practices. For instance, while direct ingestion of spray liquid has been implicated in large incidents with small birds, lower spray volumes and spraying in dry conditions may make this kind of event less likely.

Where the potential for exposure is identified there is a need to be able to estimate the drinking water requirements of birds in treated areas so that the potential risk from a given concentration in surface water can be assessed. The current approach (EU 91/414 Guidance document for bird and mammal risk assessment) to assessing the water intake of birds is a single allometric equation for daily drinking water requirements. However, additional sources of water not accounted for in this equation (e.g. water contained in food and metabolic water) also help to balance the animals' daily water requirements and would affect the estimate of the amount of surface water that would have to be drunk to maintain water balance. Also, there are now improved methods for estimating the energy requirements and the quantity of different types of food necessary to meet these needs. It should therefore be possible to develop a method for including dietary and metabolic water in the calculations and improve on the above estimate.

The aims of this project are therefore to assess the potential for exposure of birds to pesticides via sources of contaminated drinking water in the UK and review methods used to estimate the drinking water requirements of birds and identify any improvements that could be made to current practice. The results will be presented to PSD in a final report summarising the findings, discussing the implications for risk assessment and making recommendations about how risk assessment procedures can be improved where appropriate.
Objective
1. Assess the potential for pesticide exposure via sources of drinking water in the UK.

2. Review methods used to estimate the drinking water requirements of birds and identify any improvements that could be made to current guidance.

3. Produce final report including any recommendations for improvements to risk assessment procedures.
Project Documents
• Final Report - SID5A : Improving assessments of the risk to birds from pesticide contaminated drinking water   (477k)
Time-Scale and Cost
From: 2006

To: 2006

Cost: £10,012
Contractor / Funded Organisations
Central Science Laboratory
Keywords
Birds              
Drinking Water              
Environmental Effects              
Pest and Weed Control              
Pesticide Residues              
Pesticide use              
Pesticides              
Plants and Animals              
Water Pollution              
Fields of Study
Pesticide Safety