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Assessment of the environmental properties and effects of pesticide degradation products - PN0930

When released to the environment, pesticides may be degraded by micro-organisms and/or chemical processes. Currently, the only approach to assessing the fate and effects of degradation products is to perform experimental studies on the compound(s) of interest. This is a drain on resources in terms of both cost and time. A more pragmatic approach could therefore be extremely useful, that could be used in Tier 1 of the risk assessment process, the results acting as a trigger for future work.

One possible alternative approach is to use data on the properties, fate and ecotoxicity of the parent compound along with modelling approaches to predict the environmental fate and effects of degradation products. A range of possible techniques are available, including:

*qualitative assessments of the metabolite molecule to assess pesticidal activity;
*the use of structure-property, structure-degradability and structure-activity relationships;
*a consideration of the relative uptake of the metabolite compared to the parent compound.

The objective of this study is to assess the suitability of these different approaches for assessing the fate and effects of degradation products and to develop a framework for assessment of pesticide metabolites in the future. These approach could be used to determine a) whether a particular transformation is a possible relevant metabolite; and b) if it is potentially relevant, what the most appropriate testing strategy would be.
The aim of this study is to develop approaches for assessing the fate and effects of pesticide degradation products. The specific objectives are to:

1. Perform a literature review of predictive methods and data on transformation products
2. Develop a framework for assessing the ecotoxicity of pesticide transformation products that involves both predictive methods and experimental testing
3. Develop qualitative methods for determining whether a metabolite is likely to have pesticidal activity
4. Validate approaches for predicting the properties and ecotoxicity of pesticide metabolites and to refine these approaches where appropriate
5. Provide the Pesticides Safety Directorate with guidance on the use of predictive approaches in the assessment of the ecotoxicity of pesticide degradation products.
Project Documents
• Final Report : Assessment of the environmental properties and effects of pesticide transformation products   (1983k)
Time-Scale and Cost
From: 2000

To: 2002

Cost: £74,729
Contractor / Funded Organisations
University - Cranfield
Environmental Effects              
Pest and Weed Control              
Pesticide use              
Plants and Animals              
Fields of Study
Pesticide Safety