New Ruling Would Put Admitted Amalgam Hazard into“Case Law”


By Leo Cashman


After a six-year journey through the court system, the case of Dr. David Barnes, DDS v. Kerr Corporation, the nation’s largest amalgam manufacturer, appears to be a sad defeat: the trial court granted Kerr’s motion for summary judgment, and this ruling was recently affirmed by the Sixth Circuit Court of Appeals. While our sympathies go out to Dr. David E. Barnes, the Tennessee dentist who had been injured by his daily occupational exposure to amalgam/mercury, there appears to be a silver lining: the federal appellate court recognized the dangers of mercury amalgams and declared that the manufacturer provided a clear and unqualified warning that its product – amalgam - is very dangerous! The appellate court’s opinion is recommended for publication, which would make the decision binding legal precedent.  The potential consequences of this ruling are fascinating.


Barnes, who used mercury amalgam fillings for the first ten years of his practice, alleged that he had been poisoned by the mercury in the amalgam fillings that he placed and removed on a daily basis.  In 1999, Dr Barnes brought a products liability case against Kerr Corporation, the manufacturer of the only amalgam products Barnes ever purchased.  Barnes retained Jim Love and Robert Reeves, attorneys most knowledgeable about mercury amalgams, to represent him. Dr. Mark Richardson, PhD, F.L. Lorscheider, Ph.D., Gary Ordog, M.D., Robert Granacher, M.D., George Colpitts, D.D.S., and other expert witnesses testified on Dr. Barnes’s behalf concerning the various scientific, medical, and dental issues that arose in the case. Kerr challenged the admissibility of Dr. Barnes’s scientific and medical testimony on the basis that it was not supported by valid and reliable published science.  However, the trial court ruled that the supporting science was valid and reliable and overruled Kerr’s motion. 


Kerr filed an ensuing motion for summary judgment claiming that its warnings were adequate as a matter of law.  Kerr also argued that the vast majority of Barnes’s exposure was not attributable to Kerr’s products, but to amalgam fillings that Barnes removed.  Because the appearance of an amalgam filling will not reveal the filling’s manufacturer, Kerr argued that Barnes could not prove that Kerr’s products actually injured Barnes.  The District Court granted Kerr’s motion.  The judgment was appealed to the 6th Circuit U.S. Court of Appeals, but on August 11th, 2005, the Court of Appeals upheld the District Court’s ruling. 


If the Sixth Circuit Court’s opinion is published, Barnes v. Kerr may profoundly change the legal landscape regarding amalgam.  Barnes argued that Kerr’s warnings addressed only mercury—not mixed dental amalgam.  Barnes admitted that he was aware of mercury’s toxicity, but testified that in dental school, he was taught that mixed dental amalgam was safe and the mercury rendered inert.  However, the Sixth Circuit’s opinion held that the warning sufficiently notified Barnes that mixed dental amalgam was dangerous.  The Court noted, “the label on each jar of dental amalgam capsules featured not only a skull and crossbones next to the word “Poison,” but also a list of illnesses, including “bronchiiolitis, pneumonitis, pulmonary edema [and] redness and irritation to [the] eyes and skin.” Likewise, the Court noted, the MSDS (material safety data sheet,  provided to all dentist buyers) warned that chronic mercury exposure could lead to “nervous irritability, weakness, tremors, gingivitis, erethism and graying of the lens of the eye.” Further, the Court ruled that the other ingredients mixed in amalgam with the mercury – silver, copper and tin – are not claimed by the manufacturer to “neutralize the danger while the dentist is working with the product.”


Attorney Jim Love filed a petition for rehearing en banc, which requests a rehearing before all of the judges sitting on the Sixth Circuit Court.  Such a remedy is normally disfavored.  If the ruling stands as written, it will become legal precedent.  The consequences of this ruling may include the following:


1)      Under the “learned intermediary” doctrine, dentists are obligated to pass along manufacturer’s warnings to their patients.  In light of the ruling in Barnes v. Kerr, dentists will be required to explain to their patients the dangers acknowledged in Kerr’s warnings. 


2)      Arguably, state dental boards will no longer be able to prohibit dentists from communicating the dangers of mercury amalgam to their patients. 


3)      In order for a dentist to obtain a patient’s informed consent, the information given to a patient concerning amalgam will change very dramatically.


4)      The Court’s opinion will provide a direct challenge to the ADA’s proclamations of amalgam safety. 


5)      In formulating a successful legal strategy, Kerr may have impaired the market for its dental amalgam product.