1. Environmental Science Division, Argonne National Laboratory, Argonne, IL 60439, USA
2. ENVIRON International Corporation, Emeryville, CA 94608, USA
3. US Environmental Protection Agency, Office of Research and Development, National Center for Environmental Assessment, Cincinnati, OH 45268, USA
4. Biomathematics Consulting and Department of Environmental and Occupational Health, Emory University, Atlanta, GA 30322, USA
5. Synergy Toxicology, Boerne, TX 78006, USA
6. Baker Hughes, Tulsa, OK 74107, USA
7. ToxStrategies, Austin, TX 78759, USA
8. TEAM Integrated Engineering, Inc., San Antonio, TX 78216, USA