Defluoridation of Drinking Water in Southern California

United States, constituted a basis for a policy statement and resolution by the state board of public health with respect to fluoride ion concentrations in public water supplies.' The board declared in the statement and resolution adopted Aug. 22, 1958, and since amended, that it had been demonstrated that with proper amounts of fluoride the occurrence of dental decay will be materially reduced, but that excessive amounts of the fluoride ion may result in objectionable dental fluorosis and are detrimental to health. One of the resolutions of the board sets forth the maximum safe amount of fluoride ion (mean monthly concentration) in domestic water supplies in relation to mean annual temperature. These maximum concentrations are as follows: 50°F, 1.5 ppm; 60°F, 1.0 ppm; 70°F, 0.7 ppm. Active interest in fluorides in water The state board of public health has supplies was again revived in Calithe authority, through powers delefornia in the 1950's, at which time the gated it in the matter of regulation of department of public health, through public domestic water supplies, to conits division of dental health, made a trol the use of waters having excessive number of epidemiologic studies correfluoride content. The board is emlating dental decay and fluorosis, tempowered hy law to order such changes perature conditions, and fluoride ion in the source of a water supply or in concentrations in domestic water supthe installation of treatment and refinplies. This work, in conjunction with ing works and such other measures as a review of epidemiologic data gathwill insure a continuous supply of safe, ered by other agencies throughout the wholesome, and potable water.