Floride
from WIKI:
Hexafluorosilicic acid is also commonly used for water fluoridation in several countries including the United States, the United Kingdom, and the Republic of Ireland. In the U.S., about 40,000 tons of fluorosilicic acid is recovered from phosphoric acid plants, and then used primarily in water fluoridation, sometimes after being processed into sodium silicofluoride.[5] In this application, the hexafluorosilicic acid converts to the fluoride ion (F−), which is the active agent for the protection of teeth.
And this also from Wiki:
Concentrated hexafluorosilicic acid is corrosive and can attack the skin.
from WIKI:
Hexafluorosilicic acid is also commonly used for water fluoridation in several countries including the United States, the United Kingdom, and the Republic of Ireland. In the U.S., about 40,000 tons of fluorosilicic acid is recovered from phosphoric acid plants, and then used primarily in water fluoridation, sometimes after being processed into sodium silicofluoride.[5] In this application, the hexafluorosilicic acid converts to the fluoride ion (F−), which is the active agent for the protection of teeth.
And this also from Wiki:
Concentrated hexafluorosilicic acid is corrosive and can attack the skin.
