Dr. William Hirzy & EPA Union on Fluoridation. Dr. William Hirzy is a chemist in residence and adjunct professor in the Department of Chemistry at the American University in Washington, D.C.. He holds a PhD in Chemistry from the University of Missouri.

Dr. Hirzy has served as the Senior Scientist for Risk Assessment for the U. S. Environmental Protection Agency from 1981 to 2004 where he authored, "Principles of Scientific Integrity," adopted as EPA's code of professional ethics, November, 1999. He has published numerous papers on fluoride, fluoridation, and many other toxicological profiles of chemicals in the environment. He has also served as the President and Senior Vice-President of the NTEU Chapter 280 - U.S. Environmental Protection Agency, National Headquarters in Washington, D.C.