Safety of Mercury in Fillings Debated
WASHINGTON (AP) _ Government health advisers questioned a federal report concluding the mercury-laden amalgam that dentists use to fill cavities is safe.
Meanwhile, consumer activists pressed for at least a partial ban on the silver dental fillings, since they expose patients to toxic mercury.
The Food and Drug Administration asked a joint panel of outside advisers to decide whether the study _ a review of 34 recent research studies _ reflects current knowledge about the risks associated with the fillings.
Meeting Thursday, panel members and consultants didn’t discuss a potential ban, but did say the report fell short of expectations.
``Just by looking at this paper, we are in a sense really limiting ourselves. I am not convinced we are doing justice to the topic at hand,″ said Michael Aschner, a professor of pediatrics and pharmacology at Vanderbilt University and panel consultant.
The study found ``no significant new information″ that would change the FDA’s earlier determination that mercury-based fillings don’t harm patients, except in rare cases where they have allergic reactions.
Consumer groups opposed to the use of mercury in dentistry dispute that conclusion. The groups petitioned the FDA earlier in the week for an immediate ban on use of the cavity-filler in pregnant women.
``Do the right, decent, honorable and God-loving thing: There needs to be an immediate embargo on mercury fillings for everyone, or at least pregnant women and children, because they are our future,″ said Michael Burke, who blamed mercury fillings for the early onset Alzheimer’s disease diagnosed in his wife, Phyllis, in 2004.
The FDA review falls short because it doesn’t lay out what questions about the safety of mercury fillings remain to be answered, said panel member Dr. Larry Goldstein, a Duke University professor of medicine.
``The ultimate question to us is, ‘Is this adequate or not?’ Without answers to those questions, I don’t know how we can judge the adequacy of this,″ Goldstein said.
Amalgam fillings, also called silver fillings, by weight are about 50 percent mercury, joined with silver, copper and tin. Dentists have used amalgam to fill cavities _ and argued about their safety _ since the 1800s. Today, tens of millions of Americans receive mercury fillings each year. Amalgam use has begun to taper off, though, with many doctors switching to resin composite fillings that blend better with the natural coloring of teeth.
However, such ``cosmetic″ fillings can’t always be substituted for amalgam, including in cases where dentists have to place large fillings in the back teeth, Dr. Ronald Zentz, of the American Dental Association, said in a recent interview.
Dentist Howard Bailit said he and his colleagues at the University of Connecticut studied the impact of a ban on mercury fillings and found it would increase costs, reduce the number of cavities filled and have an overall negative effect on oral health.
``Our recommendation is, do not ban the use of dental amalgams,″ Bailit said.
With amalgam fillings, mercury vapor is released when patients chew and brush their teeth. Significant levels of mercury exposure can cause permanent damage to the brain and kidneys. Fetuses and children are especially sensitive to its harmful effects.
Scientists have found that mercury levels in the blood, urine and body tissues rise the more mercury fillings a person has. However, even among people with numerous fillings, exposure levels are well below those known to be harmful, the FDA report said.
Dr. Roger Porter, an industry representative on one of the two panels, called the study ``very deficient″ because it didn’t address how the human body absorbs, distributes, processes and eliminates mercury.
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