An Analysis of the EPA Chemical Use Classification System and the OTS Exposure Estimation Methodology

摘要

This report contains separate evaluations of the EPA Chemical Use Classification System and the OTS Exposure Estimation Methodology developed by EPA/OTS and another contractor. The Use Classification System describes uses of chemicals in terms of two components, function and application. The results of a three-part study of the systems led to the conclusion that the system provides neither adequate application terms nor satisfactory instructions to assure that the available terms will be used in essentially the same way by the various users. The Exposure Estimation Methodology was analyzed by statistical and systems analysis methods and found to be seriously lacking. The overall scores produced by this scoring system are probably not usefully related to exposures which would occur due to a particular chemical use.