U.S. Department of Agriculture: Animal and Plant Health Inspection Service


Date of this Version

March 2001


Published in Avian effects assessment: a framework for contaminant studies . A. Hart, D. Balluff, R. Barfknecht, P. F. Chapman, T. Hawks, A. Leopold, and R. Luttik, editors. SETAC Press, Pensacola, Florida, USA, 2001.


A major part of the Woudschoten workshop was conducted in the form of breakout groups dealing with a case study each. A case study consists of a set of test results, data, and information on a fictitious pesticide which could be part of an application for authorization. The groups were asked to take the role of regulators assessing the risk to birds for a specified use. Basic data packages for each case containing a description of the use, standard toxicity data, and background information were prepared by the case study authors and distributed in advance. The groups were then asked to apply the framework to their case step by step. When the uncertainty turned out to be too high, the group selected further information and higher-tier data that would be required for the assessment. The authors of the case studies were prepared to provide such additional data which then were subject for the discussion in the further rounds. Thus, Steps 3 to 6 forming a loop in the flowchart (Figure 1-1) might have been run through several times.

A basic idea of the framework is the separate consideration of 3 timescales: short-term, medium-term, and long-term. (This nomenclature was adopted during the workshop, although in the data provided and in these reports sometimes other terms are used, e.g., "acute exposure" instead of "short-term exposure" or "dietary toxicity" instead of "medium-term toxicity"). In each case study, different combinations of timescale and exposure route could have been identified as relevant. Due to time constraints, however, the groups often focused only on certain scenarios.

The framework structure was not fully established when the groups started working and was modified as a result of discussions during the workshop. Therefore, the case studies did not precisely follow the final version of the framework. However, the case study reports are designed to show how the sequence of assessment related to Steps 1 to 6 of the final framework.