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Which fluoride compounds are added to public water supplies?

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A labeled diagram of the periodic table entry for fluorine, showing its atomic number 9, symbol F, atomic weight 18.998, electron configuration, and indicating it is a halogen and a gas at room temperature. — fluorine Properties of fluorine.

To fluoridate public water supplies, community water systems primarily use three specific fluorine compounds. These compounds are:1

Fluorosilicic acid1
Sodium fluorosilicate1
Sodium fluoride21

These substances are added to water to release fluoride ions, which help prevent dental caries (cavities) by facilitating the remineralization of tooth enamel. In the United States, most of these compounds are derived from phosphorite rock. While water fluoridation is widely recognized as a significant public health achievement, it remains a subject of debate regarding potential risks, such as dental fluorosis, and ethical concerns regarding personal choice.314