Fluoride compounds are salts that form when the element fluorine (number 9 on the periodic table) combines with minerals in soil or rocks. Some fluoride compounds, such as sodium fluoride and fluorosilicates, dissolve easily into ground water as it moves through gaps and pores in rocks. Most water supplies contain some naturally occurring fluoride. Fluoride also enters drinking water in runoff from fertilizer or discharge from aluminum factories. And of course, many communities add fluoride to their drinking water to promote dental health.
The background story of the discovery of dental health benefits of fluoride is fascinating. It may also be reassuring to some who may be skeptical about fluoride’s usefulness, since it reveals that the early researchers were unbiased. They were simply looking for answers to certain dental problems, not seeking to justify wide-scale fluoridation of the drinking water supply.
Dr. Frederick S. McKay, a practicing dentist in Colorado invested three decades in the early 1900s tracking down the cause of a certain type of tooth stain which has always been prevalent in Colorado and several neighboring southwestern states. He first determined that this staining occurred in people whose teeth were unusually resistant to decay. He later discovered, in 1931, that the staining and resistance to decay were both due to the high concentration of fluoride which occurred naturally in that region’s water supply.
From there, Dr. H. Trendley Dean and a U.S. Public Health Service team spent ten years evaluating the dental health of 7,000 children in four southwestern states with moderate to high concentrations of naturally occurring fluoride to find what concentration gave the best protection without staining. They found it to be one part fluoride in a million parts of water.
An important test began at Newburgh, New York in 1945, to see whether deliberate addition of fluoride to a water supply which had very little natural fluoride would generate the same benefit. Over another ten-year period, the children of Newburgh developed nearly 60% fewer cavities than the children of the comparable city of Kingston, where the water was not fluoridated. Since then, thousands more studies of the effectiveness and safety of fluoridation have been made with consistent results.
Fluoride health concerns
Opponents of municipal water fluoridation are fond of stating that that the bags containing the sodium fluoride used to fluoridate the water are labelled “TOXIC.” The bags contain pure sodium fluoride, which–if ingested in large quantities–is indeed toxic. In other words: don’t rip open a bag, grab a spoon and start digging in! Simply because something is toxic in high dosages does not make it toxic under all circumstances. Some substances may actually be vital essentials for life. Iodine (which is in the same periodic table group as fluorine) is also toxic when consumed in large quantities. If, however, iodine were not added to table salt, many more people would be sick with thyroid disease (goiter), because iodine is necessary for healthy thyroid gland functioning. Oxygen administered at 100% under pressure is also toxic, which is why deep sea divers do not use pure oxygen. Even pure water can be toxic if you ingest too much of it.
That is not to say that excessive fluoride is without health risks. Children of the age eight years and younger exposed to large amounts of fluoride have an increased chance of developing stains and pits in the tooth enamel, along with a range of cosmetic effects to teeth. According to the Environmental Protection Agency, exposure to excessive consumption of fluoride over a lifetime may lead to greater likelihood of bone fractures in adults. It may damage the bones, with increased pain and tenderness. Called skeletal fluorosis, it is a serious health problem, but does not generally occur from drinking water. It is more often an occupational and environmental health risk in the proximity of industries that utilize large amounts of fluoride. Crippling skeletal fluorosis is not a public health problem in the United States, as evidenced by the reports of only five cases in 30 years. It is more prevalent in some regions outside the United States.
According to the National Cancer Institute at the National Institutes for Health, “A possible relationship between fluoridated water and cancer risk has been debated for years.” The debate resurfaced in 1990 when a study by the National Toxicology Program, part of the National Institute of Environmental Health Sciences, reported an increased number of bone tumors (osteosarcomas) in male rats given water high in fluoride over the course of two years. Other studies in humans and in animals, however, have not come to the same conclusion.
According to the Centers for Disease Control, “The safety of fluoride in drinking water at levels recommended for preventing tooth decay has been affirmed by numerous scientific and professional groups. Scientists have found a lack of evidence to show an association between water fluoridation and a negative impact on people, plants or animals.”
If you remain concerned about the levels of fluoride in your drinking water, you may choose for personal health reasons to use a water filter or filtration system specifically designed to reduce fluoride. Reverse osmosis is an effective method for reducing fluoride levels. Research into the relative benefits of fluoride will undoubtedly continue, and in the meantime, water filtration is an appropriate alternative for limiting extra quantities of fluoride in your drinking water.