Re: Requested public statement by FDA on dental amalgam in response to the December 14-15 hearing
Dear Dr. Shuren:
Given the growing scientific evidence against the safety of dental amalgam as confirmed by the advisory panel at the December 14-15 hearing, the FDA should without delay place amalgam into Class Ill, requiring proof of safety.
Meanwhile, at a minimum, the FDA should immediately inform the public that the safety of dental amalgam has not been established and is now under active investigation by the FDA. At the same time, the FDA should make the public aware that scientific research indicates that a large percentage of the population is exposed to dental mercury vapor in excess of various published reference concentrations, including EPA's current minimum reference concentration (RfC).
Further, the FDA should advise the dental profession and the public to consider other approved non-mercury dental restoration materials until such time as the safety of amalgam is verified as required by law. The FDA should note that existing amalgams should not be removed unless adequate precautions for patient and staff protection are followed in compliance with existing OSHA guidelines, to avoid dangerous levels of additional mercury exposure.
Finally, the public is advised of numerous health concerns described at the December 14-15 hearing, particularly to vulnerable subpopulations including the developing fetus, children through age 12, persons with genetic susceptibilities that may be unidentified, and persons with concurrent exposures to lead, which also may be unidentified. 1 2
Pursuant to its duty to protect public health, the FDA must take immediate steps to protect these groups by prohibiting the use of amalgam for these subpopulations. Moreover, the public should receive a general warning that there is risk for all who receive these fillings.
The FDA's reevaluation of amalgam safety will undoubtedly be a lengthy process. Thus, during this interim period, it is imperative that the public know of the health risks, particularly to vulnerable subpopulations. Warnings on this and all other relevant topics should be placed on the FDA web site immediately.
This urgent public notice is needed not only to prevent further harm, but to correct the wide misunderstanding by the media, the public, most physicians, and many dentists, that amalgam cannot cause disease -- a misunderstanding that hinders proper investigation and regulation of this ubiquitous, insidious toxin.
To recap the IAOMT's position, concerns about amalgam rest on the following concepts:
• all mercury exposure should be avoided if possible; 3 4
• set dental amalgam does release measurable mercury in ionic, vapor, and particulate form; 56
• human and animal studies show that in situ amalgam yields considerable exposure to mercury, including heightened exposure during placement and removal; 7 8
• dental mercury is widely disseminated throughout the body, accumulating in critical organs; 9 10 11 12
• plausible biological mechanisms of action are consistent with population pharmacokinetics (PPK); 13
• epidemiological studies link amalgam to human and animal pathophysiology; 14 15 16 11 18 19 20 21 22 23 24 and
• a 2010 meta-analysis demonstrates a causal link between mercury and Alzheimer's Disease. 25
On the other hand, the pro-amalgam position rests largely on anecdotal evidence arising from 150 years of amalgam usage. In addition, certain flawed population studies are cited as evidence of safety. 26 27 But a careful reanalysis of the Casa Pia study reveals a dose-dependent increase in coproporphyrin, 28 which demonstrates cogent evidence of harm from a typical amalgam exposure in a healthy young adult population.
David and Mark Geier
The FDA was charged with evaluating and classifying medical devices in 1976. Amalgam has been used for over a century and was generally regarded as safe. Over the years, the debate over amalgam's safety has waxed and waned. As a result, amalgam manufacturers have been able to successfully shirk the burden of proving safety, which should rightfully be assigned to them.
If it assigns the burden to prove harm to U.S. consumer groups, FDA condemns itself to perpetual study and inaction. This will result in an ineffective agency and an unprotected public, devastated by preventable degenerative disease.
Matthew Young, DDS, AIAOMT President, IAOMT
P.S. The Dental Products Panel of the FDA convened in 1991 to consider the issue of safety versus toxicity from mercury/silver fillings and heard the testimony of one of the world's foremost and eminent authorities on mercury, Lars Friberg, M.D., Ph.D. of the Karolinska Institute, Stockholm, Sweden:
"In conclusion, we consider that dental amalgam, from the strictly toxicological point of view, is an unsuitable dental filling material. It is our opinion that, in the future, steps should be taken to use, as far as possible other material than amalgam. In the interim we find it highly appropriate to classify the mercury used in dentistry as a class Ill device." FDA Transcript 3/15/91, p. 81.