By the time it reaches the tap, most drinking water in Kansas has been treated with all kinds of chemicals.
Chlorine, ammonia, alum, phosphates and polymers are among the most commonly used.
But of the hundreds of chemicals certified for use at water treatment plants, only one seems to excite public attention and controversy: fluoride.
And the clamor this year over the additive probably is as loud in Wichita as it is anywhere else in the U.S.
Kansas’ largest city for many years has been among the minority of American cities that do not fluoridate the drinking water. As is, Wichita’s water, drawn from Cheney Lake and aquifers, has a naturally occurring or “background” fluoride level of about 0.3 parts per million. One ppm is equivalent to 1 milligram per liter of water.
A group of residents — Wichitans for Healthy Teeth — has been circulating a petition asking city officials to boost the level of fluoride in the city’s water to 0.7 ppm as a way to combat tooth decay, especially among low-income persons who might not have regular access to dentists. About 8,300 signatures have been collected so far.
"Fluoridated water can reduce decay by about 25 percent," said Dr. Sara Meng, chair of Wichitans for Health Teeth. "A very conservative estimate of how much can be saved is $4.5 million annually, in preventing fillings and basic services. That does not count all the crowns, root canals and other major services."
If the group were successful, the city’s residents would experience no tactile differences in their water. It takes about 600 milligrams to equal a quarter teaspoon of salt, so 0.7 ppm of fluoride in the water would be nothing a normal person could taste or feel.
But that’s not what bothers the opponents of fluoridation in Wichita who have organized under the banners of Wichitans for Pure Water, a new group, and Fluoride Free Kansas, which launched its website in the late 1990s to fight an earlier effort to fluoridate the water.
Spokespersons for the opponents say the potential health hazards of fluoride, added at treatment plants in industrial quantities, aren’t fully understood. Some argue that government has no right to put what they consider medication in the drinking water.
"Fluoride is not the end-all, be-all to preventing cavities that we once thought it was, and there are potential side effects. We need to be investigating these," said Michael Hicks, volunteer executive director of Wichitans for Pure Water.
Health experts, however, say long-experience and research have shown the benefits of fluoridation far outweigh potential risks, which are inconsequential if the fluoride is used appropriately.
"The fact is, scientists involved in this have a very detailed and deliberate knowledge of (fluoridation),” said Kip Duchon, a fluoridation engineer at the federal Centers for Disease Control and Prevention. “We struggle because it's difficult for us to explain very complex things in lay terms."
That makes it relatively easy, he said, for people to stir up doubts and stoke fears about fluoridation based on misinformation.
Peer-reviewed research on the subject has convinced public health experts that fluoridation is safe and effective. But there are a few scientists who say their research suggests otherwise, and that their findings have been marginalized.
One of those is Albert Burgstahler, University of Kansas emeritus professor of chemistry and editor of the journal "Fluoride."
The journal focuses on the potential problems of fluoride, providing a venue for the “marginalized” researchers. For example, a report by a New Zealand scientist published in the journal in July 2011 concluded that the additive could cause cognitive impairment and that "the only assuredly safe level is zero" fluoride in drinking water.
Burgstahler declined requests to be interviewed, citing unfair treatment by the media in the past, but offered some information to KHI News Service via email.
"The public needs to have access to the best available evidence to make wise decisions. Asking the public to have faith in endorsements and opinions is not the same as seeing actual evidence," Burgstahler wrote via email, attaching several articles included here.
He said his journal has been published since 1968, “but has been deliberately excluded from coverage by Medline," for reasons he said were outlined here.
Medline is the index of medical journals maintained by the National Institutes of Health.
'Poison is the concentration, not the substance'
Among the concerns fluoride opponents commonly cite is the way most large water treatment plants add it in the treatment process, by pumping in hydrofluosilicic acid.
The acid is a byproduct of phosphate production. The opponents generally describe it as a "toxic waste," added to drinking water despite the fact that no studies have been done on its possible health effects.
→ Related story: Kansas’ largest city and fluoride debate have long history
→ Find out whether your water is fluoridated on the CDC's website.