§ Mr. David Mitchell
asked the Secretary of State for the Environment if in forming his policy on fluoridation he took account of the fact that, whereas the naturally occurring sodium or calcium aluminofluorides and sodium or calcium ferrofluorides are highly stable chemical complexes able to withstand any action by stomach secretions, the presence of fluoride ions arising from hydrolysis of the fluorosilicic acid or sodium silicofluoride when added to water may give rise to the formation in the stomach of hydrofluoric acid; and whether this is a toxic or a dangerous chemical.
§ Mr. Moyle
I have been asked to reply.
Normally sodium, calcium and magnesium fluorides are the naturally occurring fluorides in water and generally they exist in water as the simple fluoride ion. Occasionally, some of the naturally occurring fluoride will be present as complex fluorides, such as aluminofluorides and ferrofluorides. Generally, however, fluoride will be present in water as the fluoride ion whether it is naturally occuring or artifically added.
Extensive studies both here and abroad have not shown any harm to health associated with one part per million of fluoride ion in water during 81W periods of over 30 years in North America and over 20 years in the United Kingdom for which fluoridation has been practised or during the longer periods for which similar proportions of fluoride have been present naturally in the water supplies of some communities.