HC Deb 14 December 1982 vol 34 c110W
Mr. Lawrence

asked the Secretary of State for Social Services whether sodium fluoride, sodium silicofluoride and hydrofluosilicic acid have ever been tested to ensure their safety as drugs.

Mr. Geoffrey Finsberg

Scientific evidence has shown that the addition of fluoride to the water supply at a level of one part per million for the prevention of dental caries is safe and effective. It is not relevant, except technically, which fluoride compound is used, since at the recommended dilution all fluorides are fully dissociated into component parts known as ions, which are identical in physical, chemical and biological properties, irrespective of the compound from which they are derived.