Few noticed in November when the American Dental Association alerted its members via e-mail of a possible problem with giving babies fluoridated water:
The ADA, long among fluoride‘s biggest advocates, wrote that parents of infants younger than a year old “should consider using water that has no or low levels of fluoride” when mixing baby formula.
Public health agencies in some states, like Vermont and New Hampshire, responded by issuing warnings through the media based on the ADA e-mail.
But it would be four months before Florida’s Department of Health would relay the ADA’s message on its Web site along with its own seemingly contradictory footnote: “Mixing formula with fluoridated water poses no known health risks.”
Neither Hillsborough nor Pinellas counties’ water utilities – both of which use fluoride additive – passed along the warning.
So is fluoridated water safe for infants? It depends on whom you ask.
The issue for the ADA and for babies is fluorosis, a condition caused by too much fluoride that damages the enamel of teeth. In its milder forms, fluorosis causes white specks or streaks to appear. More severe cases involve dark staining and pitting of tooth enamel, which can increase the likelihood of decay and infection.
Both sides in the fluoride debate agree severe cases are rarely seen in those whose water is fluoridated at recommended levels. Mild fluorosis is more common and fluoride backers have argued for years that such cases are cosmetic and not harmful.
Yet some scientists warn even mild to moderate cases may lead to more significant problems.
Two things led the ADA to issue its e-mail, said Daniel Meyer, the group’s senior vice president of science and professional affairs. One was an October announcement by the Food and Drug Administration allowing health claims on bottled fluoridated water – except when marketed to infants.
The other was a report released in March 2006 by the National Research Council, which had been asked by the Environmental Protection Agency to evaluate the federal safety limits for fluoride that naturally occurs in drinking water. The safety limit: 4 parts per million.
The report found that the EPA limit is too high and associated with harmful dental effects and an increased risk of bone fractures. Not addressed in the report was the safety of treated water supplies – which have much lower concentrations. Pinellas and Hillsborough counties average around 0.8 parts per million.
The report also concluded that additional research was warranted because of previous work that had suggested links between fluoride and lowered IQs in children and bone cancer. And it raised questions about the connection between baby formula reconstituted with fluoridated water and fluorosis.
In light of the report and the FDA’s new rule, the ADA’s Meyer said a decision was made to send the e-mail, but he made clear that his group’s overall position supporting fluoridating water supplies was unchanged.
“The overwhelming evidence, ” Meyer said, “is that at the proper levels, fluoride is very effective and very safe.”
That some should treat the ADA e-mail with more gravity than others is not surprising. Adding fluoride to drinking water to prevent tooth decay has been a public health staple for 60 years. Yet skeptics have claimed the practice does more harm than good.
The rhetoric can be extreme. Supporters have been slammed as lapdogs for the chemical fertilizer industry that benefits by selling its waste to water suppliers as a fluoridation agent. And critics are often derided as deluded fearmongers blind to the support fluoridation has from the scientific community.
With a 6-1 vote of the Pinellas County Commission in 2004, about 600, 000 residents joined the estimated 170-million people nationwide whose water is fluoridated.
St. Petersburg, Dunedin, Gulfport and Belleair were already adding fluoride to their water. Pinellas supplies water to all other county residents. Hillsborough County, Tampa and Temple Terrace also fluoridate.
After learning of the ADA e-mail last year, Pinellas Utilities Department director Pick Talley said he contacted the state Health Department and the Centers for Disease Control and Prevention to gauge the seriousness of the threat. No public outreach was warranted, Talley said he was told, so his department was silent.
“We kind of follow the mainstream medical advice on fluoridation, ” Talley said. “There are a lot more serious issues that mothers need to know about when it comes to their infants.”
Similarly, Hillsborough County utility officials stayed mum, doubting the significance of the ADA e-mail.
That attitude infuriates Tom Nocera, a Clearwater resident who has blasted Pinellas County for its decision to fluoridate.
“They are trying to protect policies that have been in place for a number of years, ” said Nocera, 58, a federal government employee who works in disaster relief. “They don’t want to be proven wrong.”
Kathleen Thiessen, one of the NRC report’s 12 authors, is sympathetic to Nocera’s view. A scientist who specializes in assessing toxic risks, Thiessen said studies done overseas have associated mild to moderate fluorosis with lower IQs, endocrine system problems and skeletal damage.
Thiessen, who along with two other authors of the report have gained reputations as fluoride skeptics, said the ADA’s e-mail should be of particular concern to poor parents enrolled in the federal government’s Women, Infant and Children Nutrition Program.
For the most part, parents can use WIC checks to buy only powdered or condensed formula, which must be mixed with water.
Neither the ADA e-mail nor the NRC report has led to a groundswell of skepticism about fluoridation. But they have been affirmation for former Pinellas County Commissioner Barbara Sheen Todd, who cast the lone vote against adding fluoride to the water supply.
“The very things that I feared are now the things that are showing up, ” Todd said.
What goes in your water?
Like much about the fluoride debate, fluorosilic acid can be made to appear better or worse simply by how it’s described. The acid is what’s added to water supplies to fight tooth decay.
Critics of the process call the acid an industrial waste product. Supporters prefer industry byproduct.
Whatever it’s called, the major portion of the fluorosilic acid added to the nation’s water supply comes from Florida’s phosphate fertilizer industry. Here’s how:
Florida’s phosphate rock is about 3.5 percent fluorine. To make phosphoric acid for fertilizer, the rock is mixed with sulfuric acid. The mixture produces a gas called silicon tetrafluoride. The gas is sent through ductwork and a water scrubber to create fluorosilic acid, a clear liquid that in high concentrations is toxic. The acid is what fertilizer companies sell as a fluoride additive. It’s diluted to what’s considered a safe level when pumped into water supplies.
Source: Florida Institute of Phosphate Research