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Addressing interspecific variation in sensitivity and the potential to reduce this in ecotoxicological risk assessments - PN0932

Current regulatory risk assessment of pesticides under the Plant Products Directive (91/414/EEC) requires potential ecological risks to be evaluated through a tiered testing system. Risk is initially evaluated using a base set of single-species laboratory toxicity tests. If risk is not shown to be acceptable, then higher tier tests (e.g. multispecies mesocosm studies) may be required in order to determine impacts under more environmentally realistic conditions. Because multispecies studies are often difficult to conduct and interpret additional approaches have been proposed to further characterise potential risks identified in a preliminary assessment. One such approach is to conduct further single-species studies with a wider range of species in order to reduce the uncertainty associated with interspecific extrapolation. The proposed project evaluates the use of additional single-species toxicity information, in particular the application of species sensitivity distributions, in risk assessment. It involves a detailed literature review, case studies on selected compounds and the generation of data to fill identified data gaps.
1. Collate and review single-species toxicity test and mesocosm information for selected compounds. Identify key data gaps.
2. Conduct single-species toxicity tests to address selected key data gaps.
3. Use the single-species toxicity database to investigate how species number, species identity and distribution model influence the assessment of risk.
4. Evaluate the advantages and limitations of single-species approaches for risk assessment with particular reference to ecological realism and ecosystem protection.
5. Disseminate information, prepare outputs, identify research/data requirements.
Project Documents
• Final Report : Addressing interspecific variation in sensitivity and the potential to reduce this source of uncertainty in ecotoxicological assessments.   (1299k)
Time-Scale and Cost
From: 2000

To: 2002

Cost: £98,901
Contractor / Funded Organisations
University - Sheffield
Environmental Protection              
Fields of Study
Pesticide Safety