Facing lawsuit, FDA reviews amalgam

Should pregnant women and parents of small children be warned against amalgam restorations? Should dental assistants, or dentists themselves? After tussling with such questions periodically since 1980, the FDA is once again asking for public comments.

The 90-day comment period, which began April 28, 2008, and will end July 28, 2008, will focus on new labeling requirements that the agency first proposed in 2002.

Why solicit comments now after years of silence? No one at the FDA responded to requests for an interview on that question. In an e-mail to DrBicuspid.com, FDA spokesperson Peper Long wrote, "Based on this high number of comments as well as the discussion of the available medical literature at a 2006 Advisory Committee meeting, we decided to reopen the comment period for additional input from the public."

Many of the comments in 2006 -- which numbered more than 2,000 -- came from Consumers for Dental Choice, Moms Against Mercury, and other plaintiffs who filed suit in federal district court last December to halt the use of amalgam fillings. In mid-March, the groups offered to suspend legal action if the FDA took steps to further regulate dental amalgam.

The plaintiffs argue that the agency has been legally required to re-examine the classification of amalgam and has never done so, despite repeated promises that it was working on it to members of Congress and even to an Appeals Court judge last year. The plaintiffs also want the FDA to prepare an environmental assessment.

On May 7, Charles G. Brown, attorney for Consumers for Dental Choice, said he had filed for an injunction against the use of amalgam until the FDA regulates the substance. He said a hearing is scheduled May 16 in the U.S. District Court for the District of Columbia at 2 p.m.

Freya Koss, an amalgam critic who has testified before FDA advisory groups and Congress, called the new 90-day comment period "just another stalling tactic" that she predicted "will come back to bite them."

ADA spokespersons also declined to be interviewed on the topic. "The ADA welcomes additional review of scientific studies on the safety of dental amalgam fillings," spokesperson Lydia Hall wrote in an e-mail.

So what would the new regulations mean? At the moment, amalgam is in an FDA device category (Category I) that essentially means it is unregulated. The 2002 proposed rule would put amalgam in Category II, where it would get more scrutiny.

More specifically, the agency proposed that dental amalgam products list their exact ingredients on their labels. "By doing so," the FDA proposal states, "the clinician would be made aware of all materials he/she is placing in a patient's mouth, and would be able to avoid use of the product if the patient had known hypersensitivities to ingredients in amalgam products."

Now the FDA is asking whether labels should also warn against amalgam restorations in "in sensitive subpopulations composed of individuals who respond biologically at lower levels of exposure to mercury than the general population."

Who might be included in such subpopulations? The agency wants advice on that, as well: "If so, which subpopulations should be included (e.g., children under age 6, pregnant and lactating women, hypersensitive or immunocompromised individuals)?"

The agency has struggled for years to reach a definitive conclusion on such measures. In 2004, an FDA panel determined that there was no evidence of risk from dental amalgam -- even to pregnant women -- but a 2006 committee disagreed. An FDA Web site meant for consumers notes "the possibility that dental amalgam could pose health risks that are not yet scientifically known."

In answer to a question about whether pregnant women should get them, the FDA Web site says, "The recent advisory panel believed that there was not enough information to answer this question."

Some U.S. jurisdictions already require warnings that pregnant women and the parents of children be warned that amalgam contains mercury, which can cause birth defects.

In the meantime, pressure is mounting to restrict amalgam for environmental reasons. Late last year, before a hearing of the House Committee on Oversight and Government Reform, ADA representative Rod Mackert, D.M.D., Ph.D., told the committee that no law is needed to force dentists to put mercury-trapping devices in their wastewater systems because ADA is urging members to do it voluntarily. Dr. Mackert, a professor at the Medical College of Georgia in Augusta, said the ADA has added amalgam recycling to its "Best Practices" recommendations.

The ADA and state dental associations often find themselves attempting to fight off state and local regulations that would require dentists to recycle. According the Environmental Protection Agency (EPA), 12 states now spell out disposal guidelines for dental practices, and nine do for hospitals, which also use devices containing mercury. Norway, Sweden, Denmark, and Canada all have restricted amalgam use. What happens in the U.S. will depend -- at least in some measure -- on the next three months of comments.

Want to chime in? Find out how to submit comments to the FDA here.