A bill mandating fluoride in Louisiana water systems passed fairly easily in 2008. But that doesn’t mean no one was against the idea.

“This one snuck up on us,” says Marylee Orr, executive director of the Louisiana Environmental Action Network, even though LEAN has three people who watch the Legislature. “It may be time to do some educational outreach. We’re hoping it’s not too late.”

Paul Connett, Emeritus Professor of Chemistry at St. Lawrence University and possibly the nation’s foremost fluoridation critic, argued at LEAN’s annual conference in October that “fluoridation must be stopped worldwide.”

The new law allows residents to opt out through a petition signed by at least 15% of registered voters and a municipal election, so a grassroots campaign could potentially stop fluoridation in many communities. Given the current budget crunch, the state might not want to spend the money to pay for fluoridation, though supporters say the investment would be more than worth it.

Fluoride is a mineral compound containing the element fluorine. While the substance occurs naturally, fluoride is added to toothpaste and public water systems to prevent tooth decay. About 40% of Louisiana residents have fluoridated tap water, compared to more than 64% nationwide, according to the Louisiana Dental Association. Too much fluoride can lead to tooth discoloration and brittle bones, and some studies have shown a connection to lower IQ scores in children. But proponents call fluoridation, within safe levels, one of the most important public health advances of the past century.

“[Fluoridation] is almost the ideal public health measure,” says William Bailey of the Centers for Disease Control and Prevention’s Division of Oral Health. “You don’t have to go see a doctor. You don’t have to remember to take a pill. All you have to do is drink the water. That’s it.” He says $1 spent on fluoridation saves $38 in dental treatment costs.

While the main benefit comes from direct application to the teeth, children who ingest fluoride develop stronger teeth, he says. Bailey concedes fluoridated water in infant formula might lead to mild fluorosis, which causes tooth discoloration. He also recommends parents teach their kids not to swallow a lot of toothpaste when brushing. But he says fluoride levels resulting from community fluoridation do not lead to serious health problems in children or adults. Most fluoride added to community water systems is a byproduct of fertilizer production, but Bailey says that’s no reason to be afraid of it.

C.J. Richard, a Walker dentist and local representative of the Louisiana Fluoridation Advisory Board, says when the LSU School of Dentistry was temporarily relocated to Baton Rouge after Hurricane Katrina, the faculty found the middle-class population of Baton Rouge seemed to have more cavities than poor people from New Orleans. New Orleans, unlike Baton Rouge, has fluoridated water.

“Generally speaking, when fluoride is at the optimum level in community water supplies, you can see anywhere from a 40% to 60% reduction in the occurrence of cavities,” Richard says.

The optimum level is about one part per million; slightly lower in warmer climates where people are expected to drink more water, slightly higher in cooler climates. The Environmental Protection Agency allows up to four parts per million. Richard says children whose teeth are first developing up to age 14 see the greatest benefit.

“There have been over 750 studies. Not one has shown detrimental effects to fluoride,” he says. He finds it ironic that right-wing groups like the John Birch Society were the earliest opponents of the 60-year-old practice, claiming fluoridation was a communist plot, while these days opposition comes from Greenpeace or the Sierra Club, he says.

The city of Crowley, which draws water from a single well, spent close to $50,000 on engineering, equipment and implementation, says Susan Jeansonne, program manager of the state’s oral health program. But if the water comes from multiple wells, like in Baton Rouge, it becomes far more expensive.

The law requires systems serving 5,000 customers or more submit cost estimates to the state by March, and Jeansonne says it’s impossible for her to say at this point how much fluoridation might cost here. Baton Rouge Water Company did not return calls seeking comment. The Louisiana Office of Public Health estimated fluoridation in every unfluoridated community in the state with more than 10,000 homes would cost about $6.5 million, the LDA says.

Jeansonne says the state receives enough grant money to fluoridate maybe one or two systems a year, so Louisiana is going to have to find other funding sources. In Mississippi, a private endowment pays for fluoridation. Privately owned systems might end up passing the costs along to their customers, which could be as little as $1 per month.

“There’s an overwhelming amount of evidence to support the benefits, both scientifically and clinically,” says Dionne Richardson, the oral health program’s director. One study from the mid-1990s suggested Medicaid-eligible children in nonfluoridated communities were three times more likely to need dental treatment in a hospital, and the cost of dental treatment for those children was about twice as high.

“We’re very excited about the legislation being passed,” Richardson says.

“It is an absolutely absurd practice,” says Connett, who is a founding member of the Fluoride Action Network.

He says organizations such as the American Dental Association have staked their credibility on fluoridation, and are likely worried about legal liability for their longtime support of the practice. He says the U.S. government has never done some of the most basic work needed to prove fluoridation is safe; for example, he says there’s never been a large study looking for correlations between dental fluorosis, the telltale sign of too much fluoride, and lower IQ, lower thyroid function or bone fractures.

“We’re just flying blind, and we’ve been flying blind for 50 years,” Connett says. “Somewhere along the line, protecting this policy has become more important than protecting the public’s health.”

Connett says there isn’t an adequate margin of safety between what’s considered a safe dose and the unsafe level. One study found that fluoride could lower IQ by a few points at levels as low as 1.8 parts per million, he says, while fluoride levels in some communities are as high as 1.2 parts per million.

In essence, Connett and other opponents want to apply the so-called precautionary principle: When in doubt, leave it out. Do more studies if you want, but take the fluoride out first.

“I can tell you a few years ago I thought fluoridation was a great idea. But then I started taking a look at the research, and that changed my mind entirely,” says Howard Mielke, a research professor of chemistry at Tulane. “I’m afraid the people who are pushing it the hardest are the people who have the most to gain by selling it,” namely, fertilizer producers who have the fluoride waste product to get rid of.

The benefits of applying fluoride directly to the teeth are universally recognized, but even then, if you swallow more than just a pea-sized amount of toothpaste, you should probably call the poison control center, he says.

“We should be protecting people from exposure,” Mielke says, “not putting it into sources that are so common such as water.”