§ Mr. Rookerasked the Secretary of State for the Environment what is the source of the compounds of fluorine used to fluoridate the public water supply; how much is used per year; if there is any import content; what is the cost of the compound; and on whose Vote the cost falls.
§ Mr. MacfarlaneThe compounds of fluorine used to fluoridate water supplies are manufactured by the chemical industry from natural mineral sources. Approximately 1,500 tonnes of hexafluorosilicic acid, which contains 16 per cent. fluorine, are used per year at an ex-works cost of about £83 per tonne. Approximately 200 tonnes of imported disodium hexfluorosilicate, which contains 60 per cent. fluorine, are used per year at a cost of about £180 per tonne. The cost of the compounds is borne on the Department of Health and Social Security Vote.
§ Mr. Rookerasked the Secretary of State for the Environment who are the known suppliers of the fluorine compounds referred to in clause 1(4) of the Water (Fluoridation) Bill.
§ Mr. MacfarlaneThe main suppliers of hexafluorosilicic acid are Norsk Hydro Fertilisers Ltd. Currently the main suppliers of disodium hexafluorosilicate are Chemical and Feeds Ltd.