Water fluoridation of drinking

There are two useful side products. The H2Sip6 is shipped as a 20-25 % aqueous solution for fluoridation of drinking water. Fluorosilicate salts find use in ceramics, pesticides, wood preservatives, and concrete hardeners. Uranium, which occurs in many phosphate rocks in the range of 0.005-0.03% of UsOg, can be extracted from the dilute phosphoric acid after the filtration step, but this is not a primary source of the radioactive substance. The extraction plants are expensive and can only be justified when uranium prices are high. 

Fluoridation of drinking water has been shown to be highly effective in reducing the incidence of childhood dental caries [128,129], Earlier results were better,... 

M.E. Suarez-Almazor, G. Flowerdew, L.D. Saunders, C.L. Soskolne, A.S. Russell, The fluoridation of drinking water and hip fracture hospitalization rates in two Canadian communities, Am. J. Public Health 83 (1993) 689-693. 

Fluoride therapy and fluoridation of drinking water has played a significant role in deccreasing the dental caries. The incidence of dental caries can be significantly decreased by adding fluorides into the drinking water supply. Fluorides prevent decalcification of the structure of tooth by inhibiting bacterial enzymes which produce lactic acid. Fluorides also increase the tooth resistance to acid decalcification. 

The fluorosilicate acid can be used for fluoridation of drinking water, and fluorosilicate salts find use in ceramics, pesticides, wood preservatives, and concrete hardeners. The phosphoric acid can be purified by a solvent extraction process (Fig. 2). 

The Asp of hydroxyapatite, Ca5(P04)30H, is 6.8 X 10-37. Calculate the solubility of hydroxyapatite in pure water in moles per liter. How is the solubility of hydroxyapatite affected by adding acid When hydroxyapatite is treated with fluoride, the mineral fluorapatite, Ca5(P04)3F, forms. The Asp of this substance is 1 X 10 60. Calculate the solubility of fluorapatite in water. How do these calculations provide a rationale for the fluoridation of drinking water ... 

Tooth enamel is composed of the mineral hydroxyapatite, Ca5(P04)s0H, which has a Ksp of 6.8 X 10 . The molar solubility of hydroxyapatite is 2.7 x 10 mol/L. When hydroxyapatite is reacted with fluoride, the OH is replaced with the F ion on the mineral, forming fluorapatite, Ca5(P04)3F. (The latter is harder and less susceptible to caries.) The Ksp of fluorapatite is 1 x 10 °. Calculate the solubility of fluorapatite in water. Given your calculations, can you support the fluoridation of drinking water Your answer must be within 0.5%. 

Centres for Disease Control. Achievements in public health 1900-1999 Fluoridation of drinking water to prevent dental caries. MMWR 1999 48 933-40. 

UN identification number is 1045. The NFPA 704 designation is health 4, flammability 0, and reactivity 4. The white section at the bottom of the diamond contains a W with a slash through it, indicating water reactivity. Because of the strong reactivity with other materials, it is shipped in special steel containers. The primary uses are in the production of metallic and other fluorides, fluorocarbons, fluoridation of drinking water, and in toothpaste. 

The ideal Ca P ratio of hydroxyapatite is 10 6 and the calculated density is 3.219 g/cm. Substitution of OH with fluoride gives the apatite greater chemical stabihty due to the closer coordination of fluoride (symmetric shape) as compared to the hydroxyl (asymmetric, two atoms) by the nearest calcium. This is why fluoridation of drinking water helps in resisting caries of the teeth [Park and Lakes, 1992]. 

Fluoride page of the American Dental Association, with many links to infotmation regardingfluorides and fluoridation of drinking water and toothpastes. The ADA was one of the ori nal waterfluoridation supporters, starting in the 1940s. 

Fluoridation of drinking water is employed in many places to aid in the prevention of tooth decay. Typically the F ion concentration is adjusted to about 1 ppb. Some water supplies are also hard that is, they contain certain cations such as Ca that interfere with the action of soap. Consider a case where the concentration of Ca is 8 ppb. Could a precipitate of Cap2 form under these conditions (Make any necessary approximations.)... 

Fluoridation of drinking water is employed in many places... 

The substances most commonly used for the fluoridation of drinking water... 

Fluoride -57 OH Control of fluoridation of drinking water. Dental care products and tooth enamel. Minerals, soil Etchants containing H2F2... 

Dental Public Health. The field of dental public health is involved in the epidemiology of dental diseases and applies the principles of dentistry to populations rather than individuals. Dental public health specialists have been involved in promoting fluoridation of drinking water and examining the links between commercial mouthwash and cancer. Dental health specialists assess the oral health needs of communities, develop programs to teach and promote oral health, and implement policies and regulations to address oral health issues. 

Fluoride administration has a stabilizing effect on osteoporotic human bone, and there is some evidence of reduced bone loss in areas where the drinking water is high in fluoride. Fluoridation of drinking water (to about 1 ppm) appears to have no effect on bone loss. Administration of fluoride at a high level (10 ppm) in the drinking water of mice has been found to have no effect on cortical thinning. 

Overly high conventrations of nitrate (limiting value in Table 23.1) can be reduced by bacterial denitrification, ion exchange, or reverse osmosis. The fluoridation of drinking water is discussed in 7.3.2.10. 

---