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Guidance for Residues of Concern in Ecological Risk Assessment

A pesticide (i.e., active ingredient) and its degradates of concern are collectively known as the residues of concern (ROC). It is important to identify a pesticide's degradates of concern, taking into account the chemical structure of the products formed, their prevalence (based on the pesticide use patterns and environmental fate of the pesticide and its products), and their ecotoxicity to assessed organisms.

The purpose of this guidance is to assist in determining residues of concern for pesticide ecological risk assessments. This guidance also discusses additional data, regarding pesticides and their degradates of concern, that may be needed to reduce uncertainty in these assessments.

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