From Mercola.com – November 12, 2011:
Now declassified files of the Manhattan Project and the Atomic Energy Commission shows that the original motivation for promoting fluoride and water fluoridation in the U.S. was to protect the bomb- and aluminum industries from liability
Originally, the fluoride used to fluoridate water supplies came from the aluminum and atomic bomb industries. A couple of years later, they switched to an even more hazardous waste product: hydrofluorosilicic acid from the phosphate fertilizer industry
This hydrofluorosilicic acid also typically contains arsenic, lead, cadmium, and mercury, plus a variety of other contaminants that are part of the phosphate ore, and, shockingly, it does not have to be refined or filtered prior to being shipped and dumped into municipal water supplies
Studies on the health effects and safety of fluoride have always used pharmaceutical grade fluoride—not the far more toxic hydrofluorosilicic acid from the phosphate fertilizer industry. In the last two years, only TWO studies have finally dealt with the continued use of hydrofluorosilicic acid, and found it increases lead accumulation in blood up to seven times. It also increases lead absorption in bone, teeth and other calcium-rich tissues.