The amount of mercury in the human body that comes from your dental amalgam fillings has been greatly exaggerated for years, according to a new study from the University of Michigan.
Laura Sherman, the lead author of the paper published online today in the journal Environmental Science & Technology, studied the mercury isotopes in the hair and urine from 12 Michigan dentists. Past public health studies had assumed that any mercury appearing in the urine must be a result of inorganic mercury leaking from dental amalgams, but Sherman and her colleagues could prove that plenty of the mercury was actually a different isotope that comes from eating fish.
Mercury is nasty stuff, no doubt about it. According to the National Institutes of Health, a massive overdose of inorganic mercury like that found in the dental fillings could attack the brain and kidneys, causing kidney failure. Over-consumption of the organic mercury found in fish can cause severe neurological symptoms including blindness, seizures, and death.
However, unscrupulous dentists for years have taken advantage of frightened patients by telling them that their older fillings need to be removed and replaced by lower mercury versions of the exact same fillings. Dr. Stephen Barrett for Quackwatch looked at some earlier 1990s studies and concluded that any mercury vapor that leaked from the inert dental amalgams was “far below” the amount needed to cause harm.
“One study found that people with symptoms they related to amalgam fillings did not have significant mercury levels,” he wrote. “Some studies have shown that the problems patients attribute to amalgam restorations are psychosomatic in nature and have been exacerbated greatly by information from the media or from a dentist.”
In other words, the patient is suffering from hysteria, not mercury poisoning — but it’s a profitable hysteria indeed for the unethical dentist who offers to remove and replace the fillings.
Now, I realize that every dentist has a right to drive a Mercedes, but I’m only a little bitter after an experience last year when a new dentist told me that my fillings needed to come out and be replaced with “modern” low mercury fillings.
The problem? I’d already had the fillings replaced by the previous dentist. How many times do you guys think you can run the same hustle?
I hope the University of Michigan findings will help more people understand that some people in the past have greatly exaggerated the amount of mercury that comes out of a good dental filling.
It’s my cynical opinion that at least some of these dentists never detected any mercury at all. What they detected were gold or platinum credit cards.
[US Air Force photo by Tech. Sgt. Tony Tolley via the US Navy]