Fluoride Spotlight

Scientific American, January 2008 issue featured an article Second Thoughts about Fluoride (pp. 74-81) discussing community water fluoridation focusing on the environmental perspective. Author Dan Fagin is Director of the Science, Health, and Environmental Reporting Program at NYU's Department of Journalism. He is also former President of the Society of Environmental Journalists.

The article described some research that indicates that a cavity-fi ghting treatment could be risky if overused. Recent studies "can raise the risks of disorders affecting teeth, bones, the brain and the thyroid gland." "A 2006 report by a committee of the National Research Council recommended that the federal government lower its current limit for fluoride in drinking water because of health risks to both children and adults."

While fluoridating community water supplies is presently in 46 of U.S.'s fifty largest cities, affecting 60% of the population, and has spread to Canada, the United Kingdom, Australia, New Zealand, and a few other countries, the practice is controversial elsewhere. The NRC (National Research Council) has recommended that the EPA lower their current fl uoride limit from 4 mg per liter because it may cause teeth to discolor and disfi gure, a situation called fl uorosis in children.

In adults (the article claims) the same levels increase the risk of bone fracture and possibly moderate skeletal fl uorosis--a painful stiffening of the joints. The concern is not just the EPA recommended dosage, but what additional fl uoride sources are ingested from other foods, beverages, and dental products.

The NRC panel also noted fl uoride might set off more serious problems such as bone cancer and brain and thyroid gland damage. The article states that these effects are still unproven and need more study.

Dr. Steven Levy at the University of Iowa College of Dentistry, Director of the Iowa Fluoride Study, has been closely monitoring fl uoride use in some 700 Iowa children for signs of subtle effects over some 16 years. He feels that children are probably getting more fl uoride than they need, but still supports the use of fl uoride particularly in poor oral hygiene areas.

The Indiana University School of Dentistry faculty pioneered the stannous fl uoride in Crest in 1955, and Colgate followed in 1967 with their mono-phosphated fl uoride. Many community water supplies use a cheaper silicofl uoride. The article casts dispersions on the use of hexafl uorosilicic acid. And intones that the reason for the steep decline in dental decay with fl uoride use may or may not be due to fl uoride use. The author claims that "the consensus among dental researchers is that the decline was steep and that fl uoride deserved much of the credit." NO fl uoride research studies for over 100 years are mentioned as to explaining the steep decline of decay beyond merely a "consensus."

The Center for Disease Control and Prevention lists fl uoridation as one of the ten greatest public health achievements. The ADA endorses the use of fl uoride in drinking water, and this is supported by the U.S. Health Department.

The article is poorly crafted in that it offers no defi nitive scientifi c research on the "possible" negative effects. Yes, it is true that the excess fl uoride is stored in calcium-bearing tissues such as bone and teeth, "raising fears that the chemical may produce malignant tumors." "Fluoride appears to alter the crystalline structure of bone, possibly increasing the risk of fractures." This is a signifi cant scientifi c statement based on documented research studies?

One quoted study is a 1990 U.S. government National Toxicology Program found "a positive dose-response relation for osteosarcoma incidence in male rats." "But other animal studies as well as most epidemiological studies in human populations have been ambiguous at best."

Dr. Levy does note that most of the children are ingesting greater amounts of fl uoride than recommended, but the most serious effect has been a mild fl uorosis. This is not due to the fl uoridation of the water supplies, but the excess intake of fl uoride from other sources. However the NRC panel report (not unanimously endorsed by the entire panel) has given the anti-fl uoride side reason to fi ght reducing dental decay in children.

This article is misleading. In the face of hundreds of reports and studies lauding the use of fl uoride in drinking water to reduce dental disease, the NRC report, which merely says we should further study the side effects of all fl uoride use, opens the door for the foes of fl uoride. This article purports the same conclusion while giving too much credence to the anti- fl uoride position. On one hand there is solid research supporting fl uoride and the author gives a similar but unreasonable balance to the studies where a possible conclusion against fl uoridation may be possible. Scientific American embarrasses itself in publishing this article. It offered nothing scientifi cally concrete in doing so.