ORLANDO, Fla. (Ivanhoe Newswire) — When you think of fluoride you probably think of toothpaste, or even those trays filled with sticky “goo” the dentist stuck in your mouth when you were a kid. But when was the last time you thought about fluoride in your drinking water? Chances are, you don’t think about it because it seems like it’s always been there, so it must be there for a reason … right? Before you take your next sip of water, perhaps you should know what it’s doing to your teeth.
In 1945, Grand Rapids, Mich., became the first city in the United States to alter the level of fluoride in its public drinking water supply. Today, approximately two-thirds of the U.S. population has access to fluoridated drinking water. Studies have shown there are distinct benefits to fluoridating water at the correct levels, but new research is causing some experts to question whether cities are fluoridating their water because it’s medically beneficial or because everyone else is doing it.
According to the Americans Dental Association (ADA), the main benefit to fluoridating water is simple; it’s a safe, cost effective way to prevent tooth decay. Fluoride was initially praised as a way to prevent tooth decay in children, but the benefits aren’t limited to kids. Recently published studies show the effects of fluoride on adult teeth. “The benefits for adults were published in the Journal of Dental Research this year, and they found that, looking at all the studies on the use of fluoride, it was a benefit, and the use of water fluoridation was also a benefit,” Howard Pollick, B.D.S, M.P.H, ADA spokesperson and professor at the University of California, San Francisco Dental School, told Ivanhoe.
Despite the benefit of preventing tooth decay, some experts say there are negative effects associate with fluoride. The most common adverse effect caused by ingesting high levels of fluoride is dental fluorosis, which is a medical condition marked by spotting on the teeth. The severity of dental fluorosis can vary from light speckling to dark staining, and, in some cases, teeth can develop deep pits. It’s debatable whether dental fluorosis is a medical threat or just an aesthetic inconvenience. “It really doesn’t effect the function of the tooth,” William Maas, D.D.S, M.P.H, director of the division of oral health at the Center for Disease Control (CDC), told Ivanhoe.
There have been cases in which other negative effects were linked to fluoride. “A high enough exposure to fluoride for a long enough time will lead to severe bone and joint problems,” Kathleen Theisen, Ph.D., senior scientist at SENES Oak Ridge, Inc., Center for Risk Analysis, in Oak Ridge, Tenn., told Ivanhoe. “I don’t see much that would justify the use of fluoride in water, given the substantial risks of doing harm,” Dr. Theisen added. There are also growing concerns that fluoride may pose a potential risk to the thyroid. Dr. Theisen recently co-authored a review of fluoride/thyroid information for the National Research Council. The review notes that fluoride’s possible effects on thyroid are most likely to occur in a person who is iodine deficient. Harmful effects caused by fluoride are associated with exposure to high levels over a long time. In fact, laws now exist to protect people from the damages ingesting high levels of fluoride can cause.
The Environmental Protection Agency has mandated that the level of fluoride in any public water source may not exceed 4 milligrams per-liter, or four parts-per million. “That level was set to protect against the only adverse effect that is known to occur in the United States — skeletal fluorosis. There have only been four or five cases in the U.S. ever; it requires a very high level for a very long time,” Dr. Maas said. Although the current maximum level is still set at four parts-per million, experts at the ADA and at the CDC agree a level somewhere around one part per-million is ideal. “Anywhere from .7 parts-per million to 1.2 parts-per million is the optimal level,” Dr. Maas said. This range of levels was determined by looking directly at the effects of different levels of fluoridated water in different areas. “When they [researchers] looked at different cities and plotted their tooth decay against their dental fluorosis, it looked like at the level of about one part per million there was a nice balance between protection against cavities, and some very little white blemishes. That was considered a reasonable tradeoff,” Dr. Maas said.
Today, the exact optimal level of water fluoridation is determined on a city-by-city basis, and can be administered very precisely. “When cities add it to the water, they have high standards. If you live somewhere that .8 parts-per million is the exact optimal level, they can put it in consistently at .8 within about a hundredth of a part per million,” Dr. Maas said. The CDC offers an application on their website that allows anyone to search for their area’s water fluoride concentration, by visiting http://apps.nccd.cdc.gov/MWF/Index.asp.
Opponents of fluoridation argue that even the recommended levels are too high. “Fluoride is listed as a drug, and it requires a prescription to be obtained. A .25 milligram tablet requires a prescription; one cup of tap water fluoridated to one milligram per-litter does not, but the intakes are the same,” Dr. Theisen said. “If a doctor or dentist thinks an individual can benefit from fluoride, he or she can prescribe it and monitor the patient for any side effects. There is no mechanism for monitoring side effects from fluoridated water, nor is there a way for an individual to avoid it except by obtaining water from another source at his own expense,” Dr. Theisen added.
Because it is legal by EPA standards to have fluoride levels in public drinking water as high as four parts-per million, there are areas of the country where people are receiving drinking water fluoridated at a level higher than the recommended maximum level of 1.2 parts-per million but lower than the legal maximum of four parts-per million. “The National Research Council report says about .5 percent of the U.S. population has fluoride levels in their water at about two parts-per million. If you live in one of these areas, you would receive an annual notice that this water isn’t recommended for use by children whose teeth are developing,” Dr. Pollick said.
Although the CDC recommends fluoridated water, at an optimal level, for just about everyone, there is one group that should avoid fluoride all together. “If an infant is exclusively formula fed, and it’s reconstituted with tap water, the child will get a very large dose of fluoride for it’s body size, and the child will be at risk for mild dental fluorosis,” Dr. Pollick said. Bottled water with the word “purified” on the label is presumably fluoride free. There are also ways to avoid letting fluoridated water into a home’s drinking water. “A water softener would take the fluoride out of the water, or reverse osmosis,” Dr. Maas said. Even if you control the water source you drink from, it may be nearly impossible to escape fluoridated water completely. Certain foods and drinks available at the grocery store contain fluoride by default. “The modern diet has so many processed foods and beverages, much of the stuff you’re eating may have been processed in a larger city where there is fluoride in the water,” Dr. Maas said.
Another reason fluoridated water is under scrutiny is because of the type of fluoride being artificially added. Calcium fluoride naturally occurs in most water supplies, but it would be impossible to add calcium fluoride to water in its natural state to increase fluoride levels. “If you put calcium fluoride in water, it won’t dissolve. It’s like a rock. The kinds of fluoride that we have in our body are very complex molecules that will break down through natural body process. So, the compounds that are used for fluoridated water have to be bioavailable,” Dr. Pollick said. These bioavailable forms of fluoride, often called silicofluoride, are easy to add and transport in a concentrated form.” Most of the fluoride comes in the form of an acid, it’s a byproduct of phosphate fertilizer,” Dr. Maas said. “You’re diluting it to about one drop of fluoride acid for every 250,000 drops of water. It doesn’t even change the Ph of the water you put it in,” Dr. Maas said. On the other side of the argument, silicofluoride is seen as potentially dangerous. “The silicofluoride product sold to municipal water supplies contains other things — it’s all a byproduct, or waste product, depending on one’s point of view,” Dr. Theisen said. “This has not been well studied, and no measurements have been reported for ordinary conditions.”
For those who believe fluoride should be supplemented in public drinking water, shortages are a growing concern. And in places, like Calgary, Alberta, Canada, a fluoride shortage is raising questions as to whether their water should continue to be fluoridated. Dr. Maas believes shortages, like the one in Calgary, reflect a shortage of the water additive supplier, rather than an absolute shortage. “In the long term we expect the disruptions to be fewer as manufacturers make new investments in production equipment, but for the near future there may be some disruptions in supply,” said Dr. Maas.
In the United States today, there are approximately 100 million people who don’t have dental insurance and pay for their dental work out of pocket. The cost of having a cavity filled or a root canal performed can be pricey. Many experts say fluoridating water to prevent tooth decay is the cheapest way to keep people from developing dental problems. The CDC estimates the annual cost for a city with more than 20,000 people to fluoridate its water to be about 50 cents per person. “If you want to save 38 dollars in unnecessary dental care for every one dollar you invest in fluoride, it’s a good idea,” Dr. Maas said.
“Just because everybody is doing it does not automatically mean that it is a good thing to do,” Dr. Theisen warned. She said she believes the individual decisions to fluoride public drinking water aren’t made with sound judgment. “I think we need more medical, dental, and scientific professionals in this country and elsewhere to look at the data themselves, rather than taking the word of the authorities and experts,” Dr. Theisen said.
The answer to whether or not water should be fluoridated isn’t as clear-cut as it seems it should be. Some see fluoride as a threat; others see it as one of public health’s greatest achievements. “Everything is a poison, it’s all about dose. What distinguishes a poison from a remedy is the dose. ” Dr. Pollick said. But should that dose be lowered? That question is under review and being investigated. “Ultimately, if a new drinking water standard for fluoride is responsibly set, I expect, based on all of the data that I have reviewed, the new standard to be too low to permit continued fluoridation of public water supplies,” Dr. Theisen said. The EPA will ultimately be responsible for deciding if allowing four parts-per million to go on as the legal limit is in the public’s best interest.
This article was reported by Ivanhoe.com, which offers Medical Alerts by e-mail every day of the week.
Print 
PDF