December 14th, 2010
01:05 PM ET
An FDA advisory committee is holding a two-day hearing to re-review the scientific basis for the FDA’s conclusion that mercury in amalgam dental fillings is not harmful to patients.
The committee initiated the hearings less than 18 months after the federal agency made the decision. Committee members are examining challenges from four consumer and dental groups that say the FDA used flawed science when it set the guidelines for mercury safety levels. Although the FDA noted there will be no vote on this, they may recommend to reverse the decision and send it to the main FDA board for review.
Amalgam tooth fillings are an alloy of 50 percent mercury, 35 percent silver, 13 percent tin, 2 percent copper, and a bit of zinc. Mercury toxicity was known in the 19th century, but amalgam's cheapness, ease of placement, and durability kept it popular. Dentists argue that mercury fillings last longer than resin composites, and are easier on the tooth. But scientists say mercury is a poison that penetrates into the body and many argue, damages human cells, especially in the brain, bones and kidneys. How much damage is still unknown, which is why the advisory committee is re-visiting the issue.
In their final rule in 2009, the FDA concluded clinical studies have not established a causal link between dental amalgam and adverse health effects in adults and children age six and older. But it did add that developing fetuses and young children may be more sensitive to the neurotoxic effects of mercury vapor.
Today, numerous professional and scientific groups testified in front of the committee, sighting the dangers of amalgam fillings. Studies and testimony presented showed a vast array of connections between mercury in fillings to such conditions as autism to bowel problems.
Dr. Anne Summers, a microbiologist at the University of Georgia who works with mercury, testified that in animal studies, those subjects with more amalgam fillings had higher levels of mercury in their bowels and feces and were found to have more mercury throughout their bodies, than if they had eaten mercury-rich fish every day.
“And they weren’t eating fish,” Summers exclaimed. “They were eating (animal} chow.”
Her studies also looked at the effects of mercury in the body on the gastrointestinal system. Summers noted, “90% of the mercury in the body goes through the lower G-I tract. The gut is very volatile.”
Dr. Mark Geier, President of Genetics Center of America, and founder of ASD centers, published a 2009 study in the journal of the Acta Neurobiologiae Experimentalis ,that looked at the effects of mercury in amalgam fillings on children with autism.
In his testimony to the committee, Geier, an epidemiologist and autism researcher said, “When we examined children with mothers who had zero to six fillings, we saw no significant effect. But when mothers had over six fillings, we found their children had a higher severity of autism, than children whose mothers had fewer fillings.”
Geier continued, “Although we don’t know why the number of fillings made a difference, you have to think of the mercury issue.”
In afternoon public testimony, many people told stories of possible toxic effects on their bodies from amalgam fillings.
Although stories and symptoms differed, all of those who testified asked one thing: Let the public know of the possible dangers in these mercury fillings. In written testimony, Dorice Maderonero, a consultant from the Hudson Valley area of New York, claimed that as a young, expectant mother, she miscarried twice following dental work.
“I know that in my visits to any physician or dentist I was never asked whether I was allergic to mercury.” said Madronero, “And I did not drink coffee, never smoked in my life and didn’t even have a sip of New Years Eve champagne"
Madronero also wrote. “There is very limited to no clinical information available regarding long-term health outcomes in pregnant women and their developing fetuses, including infants who are breastfeeding.” Madronero asked, “Can you really say you (FDA) don’t know and then conclude safety?”
James Turner an attorney representing a group known as “Citizens for Health” addressed the committee, and asked the FDA to update its website on amalgam fillings, particularly on the possible dangers to patients. “There is plenty of new data showing the effects of mercury in these fillings. We need to ask for safety," said Turner.
But Dr. William Spruill, a dentist from Carlisle, Pennsylvania and President of the Pennsylvania Dental Association, with 5,000 members, believes there's nothing to worry about when it comes to amalgam fillings.
"I've been practicing dentistry for 34 years. I have these fillings, my wife has these fillings." said Spruill. "Based on the research, I am comfortable with my dental work and I would give my kids these fillings, but they don't have cavities."
According to the American Dental Association, "Dental amalgam is considered a safe, affordable and durable material that has been used to restore the teeth of more than 100 million Americans. It contains a mixture of metals such as silver, copper and tin, in addition to mercury, which binds these components into a hard, stable and safe substance. Dental amalgam has been studied and reviewed extensively, and has established a record of safety and effectiveness."
The advisory committee will continue tomorrow. Should the committee decide to make recommendations it will send them to the FDA for consideration. Although the FDA does not have to act on the recommendations, it traditionally follows the guidance of the advisory committees
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