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| The Dangers in Your Water by: Timothy Gower One fall day in 2004, Lea Anne Burke got a call from a neighbor. Had she heard that the city council was talking about adding fluoride to their water supply in Snohomish, WA? For years, the northern end of town had received fluoridated water from the nearby city of Everett. But nonfluoridated water from the Pilchuck River ran through pipes on the south side of Snohomish, where Burke, her husband, and their two little girls live. Burke, 33, is a soccer mom and vice president of the local PTA. She studied environmental science in college and learned enough about fluoride to be convinced that she didn't want it flowing from the taps in her home. She won't even let her family brush with fluoride toothpaste. So Burke joined a small group of citizens who, last year, persuaded the city council to abandon its plan to fluoridate the water. "Until it's proven safe, why do it?" asks Burke. If you have only ever known fluoride as a champion cavity fighter that keeps your pearly whites strong, Burke's concerns may sound off the wall. After all, two-thirds of US cities and towns fluoridate water, and most US dentists agree that it prevents tooth decay. In fact, in 1999, the CDC named the fluoridation of community water one of the top 10 public health achievements of the 20th century. Yet, controversy and doubts about its safety have dogged fluoride ever since the first US city, Grand Rapids, MI, began adding it to its water supply in 1945. And now, several reports published earlier this year have tarnished fluoride's brilliant veneer. In March, a panel of dentists, toxicologists, and epidemiologists assembled by the National Research Council (NRC) determined that the level of fluoride allowed in community drinking water in this country is too high. In a cruel irony, the panel found that children who consume water containing the highest level of fluoride permitted by the EPA might actually be damaging their teeth; there was even a hint that it might depress IQ. What's more, the panel stated that consuming water with that amount of fluoride over a lifetime could weaken bones and increase the risk of fractures. And just 2 weeks after the NRC report made headlines, a Harvard study suggested that fluoridated water could cause a rare form of bone cancer in young boys. The two reports have helped fuel the passions of fluoridation opponents, a group made up of scientists and concerned citizens. They claim that adding fluoride to drinking water may have made sense once but is unnecessary now because it is available in other forms, such as toothpaste. Drinking the stuff, they say, exposes millions of Americans to needless health risks. "Fluoridation should be abandoned," says dentist Hardy Limeback, PhD, DDS, head of preventive dentistry at the University of Toronto and a member of the panel that wrote the NRC's fluoride report. "It could turn out to be one of the top 10 mistakes of the 21st century." If Limeback and other top-notch researchers at respected universities are now concerned that we're getting too much fluoride, should you be worried, too? For starters, read the label on a tube of toothpaste: Keep out of reach of children under 6 years of age. If more than is used for brushing is accidentally swallowed, get medical help or contact a Poison Control Center right away. Poison? Indeed, some forms of fluoride are used in high concentrations to kill rats and crop-eating insects. Municipal employees who add fluoridation chemicals to public water systems must wear protective clothing and respirators. Industrial workers regularly exposed to fluorine, the gas form of fluoride, have suffered skin, lung, and gastrointestinal problems; it has even been fatal for some. But at the doses most people get, fluoride behaves differently: About half of it exits quickly through the urine, while the remainder settles into the bones or teeth. The 1 mg of fluoride per liter of water (1 mg/L) recommended by the government for water systems is equal to just 1 part per million (or 1 ppm). That scant dose of fluoride has been added to water since the 1940s to fight tooth decay, and early research suggests it did the job well. A 1962 study of Newburgh, NY, one of the first communities to fluoridate its water, found that cavity rates dropped by 70% over a span of 15 years. That sort of success sounds impressive—but it's no longer relevant, opponents say. When fluoridation began, scientists believed that fluoride needed to be ingested to fight cavities, so that it could be incorporated into the enamel of developing teeth before they erupted through a baby's gums. However, most dental researchers today agree that throughout our lives, fluoride works best when it's applied directly to the teeth, where it not only shores up dental enamel but also shields it from damaging acid produced by bacteria in the mouth. That means today's fluoride toothpastes, rinses, tablets, and other dental products can do the job. At the very least, since most Americans today brush at least once a day, fluoride dental products have diluted some of the benefits of drinking fluoridated water. In 1990, researchers at the National Institutes of Health compared the dental records of 16,000 children between ages 5 and 17. Half lived in fluoridated communities; the rest did not. They found that the kids who grew up drinking fluoridated water had just 18% less tooth decay than the other children. Fluoride skeptics add that even this relatively unimpressive statistic loses much of its luster when you examine the numbers more closely. The study showed that children in fluoridated communities had 0.6 fewer decayed tooth surfaces—or about half of one cavity—than those who didn't drink fluoridated water. "That's not much of a benefit," says toxicologist Tim Kropp, PhD, of the Environmental Working Group, a Washington, DC-based nonprofit organization that opposes water fluoridation. Especially when you consider that too much fluoride can harm teeth. | |||
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