Senior U.S. health officials have squelched a Food and Drug Administration proposal that for the first time would have curbed dentists' use of mercury — one of the planet's nastiest toxins because it attacks the central nervous system — in treating Americans' decayed teeth.
The proposal, approved by top FDA officials in late 2011 and kept secret since, would have told dentists they should not use mercury fillings in cavities in pregnant women, nursing moms, children under 6 and people with mercury allergies, kidney diseases or neurological problems.
It also urged dentists to avoid using fillings that contain mercury compounds in any patient, where possible.
The proposal and its secret rejection, after a cost-benefit analysis by officials at the Department of Health and Human Services, have put the Obama administration in the awkward position of concealing for more than three years a safety communication potentially affecting millions of Americans.
The FDA has defended the safety of mercury fillings since the agency's inception in 1930 and especially during an ongoing, 23-year legal battle with consumer groups. Consumer lawyers are pressing the government to ban the compounds, as Denmark, Norway and Sweden have done.
The "safety communication" was drafted in response to citizens petitions and an FDA advisory panel of outside experts, several of whose members expressed concerns in 2010 that the agency had not gone far enough to protect vulnerable groups.
The first public hint that the agency might shift its position came during a town hall meeting in September 2011 in San Francisco, where Jeffrey Shuren, director of the FDA's Center for Devices and Radiological Health, heard from several dental patients. They described recovering from severe health problems after having their mercury fillings removed and taking chelation agents — supplements that can help the body excrete toxins.
Shuren told them he expected the agency to issue a new policy by year's end.
Instead, sometime later, the Department of Health and Human Services quietly killed the FDA's communication.
Jeff Ventura, a spokesman for both the Health and Human Services Department and the FDA, declined to comment because the government's regulation of mercury in dentistry is a subject of litigation. The citizen groups sued in federal court last year to compel the agency to respond to their petitions.
"FDA will continue to evaluate the safety of dental amalgams and will take any further actions that are warranted," Ventura said.
Left unexplained are a myriad of questions, including who made the decision, why was it made and whether any special interest group directly influenced the government to curb its warning.
Department officials concluded that the out-of-pocket costs of patients with dental insurance coverage would triple if they had to pay for alternative fillings, imposing an unfair burden on low-income Americans who might then neglect decaying teeth, according to the McClatchy news service, citing an administration official who requested anonymity because disclosure of the information was not authorized.
The price difference for patients to fill a cavity with the most popular and economical alternative, tooth-colored composite resins, can be about $100.
An American Dental Association survey in 2009 indicated 54 percent of U.S. dentists were still using mercury fillings, a durable, easy-to-use remedy for more than 160 years. However, the number of dentists abandoning those products has risen steadily over the last 20 years as concerns about the toxin's effects have mounted and alternatives have improved.
The fillings are still used in taxpayer-funded Medicaid and Medicare programs for the poor and the elderly, in the military, in prisons, on Indian reservations and by doctors serving price-sensitive patients.
The last time the U.S. Public Health Service surveyed Americans about their dental work, from 2001 to 2004, it estimated that dentists had repaired 1.46 billion teeth in 181.1 million Americans, the majority with mercury fillings.
Mercury is often described as insidious. Once in people's lungs, it moves to the bloodstream and can accumulate in the kidneys, liver and brain, where it damages the central nervous system. It has been linked to an array of health problems, including memory loss, nerve damage, autoimmune diseases, vision problems, kidney failure, depression, autism and foggy thinking. Recent research suggests it may contribute to Alzheimer's disease. It also can be lethal.
Since the FDA's proposed communication was rejected, the agency has continued to defend the safety of mercury fillings, except in people with mercury allergies.
An expert in medical ethics said he finds the secrecy about the proposed warnings troubling.
While it's reasonable to conduct cost-benefit analyses, "the government should share what it knows. It should not be hiding, it should not be yielding to lobbying of any sort," said Art Caplan, director of the Division of Medical Ethics at New York University's medical school.
If FDA officials "don't get accurate information out there, then this all shifts to the Internet and the land of the crazy and the thoughts of the goofy," he said. "People will start to be frightened and get misinformation and distorted information."
James Love, an Oklahoma lawyer who in 2009 filed one of three citizen petitions contending the agency should have acted more forcefully in a rule issued that year covering mercury fillings, took a harsher view.
"If you inject cost-benefit analysis into the equation," he said, "then we're going to justify legally poisoning people."
During the 2011 town hall meeting in San Francisco, San Diego dentist David Kennedy told FDA officials he has "seen hundreds of people's lives dramatically improve once these mercury implants were safely removed."
"I've seen infertile women make a whole family, chronic high blood pressure return to normal and multiple sclerosis victims totally recover," said Kennedy, a past president of the International Academy of Oral Medicine and Toxicology, formed by mercury-free dentists concerned the fillings are harming people.
Known in the trade as amalgam, the dental compounds consist of about half mercury blended with metal alloys that include silver and often have been presented to patients as "silver fillings." While the mercury is described as encapsulated, the fillings still release very low levels of mercury vapor that patients inhale on a continual basis — the more fillings, the more vapor. Chewing or vigorous brushing can increase the vapor release.
For decades, the FDA has agreed with dental products manufacturers and the American Dental Association that those exposure levels are not a cause for concern, citing the lack of clinical studies showing harm. Hence, the agency has never advised dentists that they should inform patients of potential health risks before placing mercury fillings in their teeth. James Turner, who is among consumer lawyers battling the agency, said the "core argument is that the public should be told about the risks."