asked the Minister for Local Government and Public Health whether his attention has been directed to published work directed to prove that the addition of fluorine to drinking water supplies reduces the incidence of dental caries in the community using the supply; and whether he will consider recommending local authorities to add fluorine to water supplies in selected cases, and to conduct the necessary surveys amongst the juvenile population of these areas to establish the value of such a procedure.
Ceisteanna—Questions. Oral Answers. - Fluorine in Drinking Water.
The answer to the first part of the question is in the affirmative. There is some evidence that in areas in which the water supply comes from wells sunk into geological formations of rock with salts of high fluorine content (such as fluorspar and apatite) the quality of the teeth of the inhabitants as regards freedom from dental caries is enhanced. On the other hand an excess of fluorine, even if slight, causes a mottling and disfiguration of the teeth. This usually occurs with a water content of fluorine of .3 parts per million of water. At a level of fluorine of 1.5 parts per million of water a generalised thickening and hardening of the bones, known as osteosclerosis occurs. Having regard to the difficulty of maintaining a suitable standard of fluorine content in water supplies, the danger likely to arise if an excess quantity of fluorine is added to such supplies and the fact that the effect of fluorine as to a reduction of the incidence of dental caries is not yet clear or proved, it is not proposed to take action on the lines suggested. I may add that in connection with the proposed nutrition survey the chemical analysis of water supplies in the larger urban areas will be carried out.
Will the Parliamentary Secretary keep this matter in mind with a view to adopting this suggestion if, at a later stage, some recent work leads him to believe it should be adopted?
Yes, I am keeping in touch with that. I read all the available literature in connection with it.