By Eulalee Thompson, Staff Reporter 
MERCURY-LADEN FISH dinners are not the only mercury source to worry about; the source of your problems could be right there in your mouth.
A whole battery of studies published within the last 10 years or so, really have nothing good to say about mercury-containing amalgams used in tooth fillings. Mercury in fillings have been linked all sort of ailments including poisoning, heart disease, depression, interruption in the normal function of human cells, kidney damage, hearing loss, irritability and chronic fatigue syndrome. To be fair, there are also many reports speaking to the benefits of dental amalgam over other material such as gold, ceramic inlays, resin-based composite materials and glass ionomers.
Mercury fillings (dental amalgam) is composed of about equal parts of liquid mercury and alloy powder containing silver, tin, copper, and sometimes lesser amounts of zinc, palladium or indium. These mercury fillings are the popular choice among dentists because they are said to be strong, durable and relatively inexpensive though substitute materials are now available. Health concerns have been raised because scientists say that elemental mercury is emitted in minute amounts as vapour. The vapour can be absorbed by the dental patient through inhalation, ingestion and by other means raising concerns about possible toxicity.
HEART FAILURE
Two Italian studies, published in the Journal of the American College of Cardiology (May 1999 and March 2000), link congestive heart failure to vastly elevated concentrations of mercury and antimony (a metallic element) in heart tissue. The researchers, from the Catholic University in Rome, compared trace element concentrations in biopsy samples from the left ventricles of patients with heart failures with those of patients with valvular disorders or no heart disease at all.
The patients with congestive heart failure (also known as idiopathic dilated cardiomyopathy) were found to have concentrations of mercury which were 22,000 times higher than those in the control groups. Concentrations of antimony were 12,000 times higher in these patients and the researchers also found elevated levels of silver, gold, chromium and arsenic. These patients had no occupational exposure to the trace elements and the scientists believe that dental amalgams were the most likely source of the mercury.
A small clinical trial of 20 patients with bipolar disorder (manic-depressive illness) was published in Journal of Orthomolecular Medicine (1998), saw improvements in symptoms when the mercury fillings were removed from the patients' mouths. The patients were measured at the start of the experiments with mercury fillings in tact and then eight months after removal of the mercury fillings. Based on mental status evaluation questionnaires the patients showed significant improvement in anxiety, depression, paranoia, hostility and obsessive compulsive behaviour when compared with a control group.
Other studies in the New Zealand Medical Journal warn that mercury vapours from dental filling can induce psychiatric symptoms (even in low concentrations) as well as depression, mental deterioration and irritability.
So much bad news on dental amalgam, then why is it still being used? Dollar-for-dollar, research is indicating that it is still the best and more durable product. The U.S. Public Health Service (1993) report stated that except in rare cases of allergic reaction, there is no health reason not to use mercury fillings.
How do you feel about chewing on mercury? Send your comments to eulalee.
thompson@gleanerjm.com.
