Water fluoridation
Health and dental organizations worldwide have endorsed its safety and effectiveness. Its use began in 1945, following studies of children in a region where higher levels of fluoride occur naturally in the water. Further research showed that moderate fluoridation prevents tooth decay.
Water fluoridation in the United States
In 1952, a Federal Regulation was adopted that stated in part, "The Federal Security Agency will regard water supplies containing fluorine, within the limitations recommended
by the Public Health Service, as not actionable under the Federal Food, Drug, and Cosmetic Act."