1. Office of Dietary Supplements, National Institutes of Health, Bethesda, MD 20892
2. Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA 30341
3. Analytical Chemistry Division, National Institute of Standards and Technology, Gaithersburg, MD 20899
4. Division of Health and Nutrition Examination Surveys, National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, MD 20782
5. Department of Biochemistry and Molecular Biology, University of Medicine and Dentistry of New Jersey, Newark, NJ 07103
6. Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN 55455
7. Department of Foods and Nutrition, Purdue University, West Lafayette, IN 47906
8. Department of Biostatistics, University of Alabama, Birmingham, AL 35294
9. Department of Laboratory Medicine, University of Washington, Seattle, WA 98195
10. Department of Medicine, Indiana University School of Medicine, Indianapolis, IN 46202
11. Clinical Toxicology Laboratory, University of Wisconsin Hospital and Clinics, Madison, WI 53792
12. Department of Biostatistics, Boston University School of Public Health, Boston, MA 02118
13. Channing Laboratory, Harvard Medical School, Harvard University, Boston, MA 02155
14. Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, WI 53792