Optimal Fluoride Levels
Water fluoridation involves the addition of a fluoride containing compound, to a water supply,
to obtain an optimal level of fluoride ion, which would best prevent the occurrence of dental caries.
Community water supply systems add fluoride to water supplies in one of three forms:
sodium silico fluoride, hydrofluosilic acid or sodium fluoride (1). Optimally the level of fluoride
would be 0.7 to 1.2mg of fluoride per liter of water. Tables of optimal levels are dependent on
the daily air temperature, see table 1.
Table # 1 (1)
Due to the fact that people tend to drink more in warm weather, warmer weather dosage levels
are much lower than those of colder weather. The maximum contaminant level, (MCL), for
fluoride, is set at 4mg/liter. Dosages above this level have been know to cause cases of
skeletal fluorosis. Skeletal fluorosis is the weakening of bones due to high levels of fluoride
being deposited in them. An MCL limit of 2mg/l was set to prevent against the occurrence of
dental fluorosis (1). Dental fluorosis is characterized by a graying of teeth. In severe cases,
the tooth enamel begins to pit. In natural ground water supplies, levels of fluoride present
have been reported as high as 25mg per liter of water (2)