1. Litron Laboratories Rochester New York USA
2. Covance Laboratories Inc. Greenfield Indiana USA
3. Charles River Laboratories Skokie Illinois USA
4. Toxicology Consulting Midland Michigan USA
5. St. George's University of London London UK
6. Integrated Laboratory Systems Research Triangle Park North Carolina USA
7. Teijin Pharma Limited Hino Tokyo Japan
8. U.S. Food and Drug Administration/NCTR Jefferson Arkansas USA