asked the Secretary of State for the Environment what information he has as to the sources of imported fluoride used for fluoridating the public water supply; and if he will make a statement.
One of the compounds currently used for fluoridation of water supplies, disodium hexafluorosilicate is imported. It is manufactured by a phosphate fertiliser company from mineral rocks containing both phosphate and fluoride.
asked the Secretary of State for the Environment what steps are taken to monitor the fluoride content in the air in the United Kingdom.
Monitoring of ambient levels of fluoride is carried out around specific industrial plants which give rise to fluoride emissions. Such plants also monitor stack emissions of fluoride as part of the control requirements laid down by the Industrial Air Pollution Inspectorate. Elsewhere, monitoring is not routinely carried out, because ad hoc studies have indicated that concentrations of fluoride in the atmosphere are generally very low, that is, between 0·5 and 1 microgrammes per cubic metre.
asked the Secretary of State for the Environment what information he has as to the fluoride level in the air breathed by people in the Birmingham conurbation.
I am advised that no industrial plants liable to give rise to fluoride emissions are situated in the Birmingham conurbation and, consequently, no monitoring of ambient levels of fluoride is carried out in this area.