The latest scientific evidence shows that the mercury in dental fillings could be behind many unsuspected diseases from hair loss and infertility to Lou Gehrig's disease (ALS).
The American Dental Association continues to maintain, as it did in 1984, that "when mercury is combined with the metals used in dental amalgam, its toxic properties are made harmless." This is the same position adopted by the British Dental Association. However, up until now this position has been based upon reverse logic, that amalgam fillings are safe because the evidence that is emerging does not prove irrefutably otherwise.
In 1993, the US Public Health Service issued a report evaluating the safety of dental amalgam. Although the report allowed that small amounts of mercury vapour are released from your fillings and can be absorbed into the body, and that these could cause small responses in that rare group of allergic individuals, it concluded that "there is scant evidence that the health of the vast majority of people with amalgam is compromised, nor that removing amalgam filings has a beneficial effect on health" (Journal of American Medical Association, 1993, 269: 2491).
The American Food and Drug Administration's position continues to be that there is no valid data to demonstrate clinical harm to patients or that having them removed will prevent adverse health effects or reverse the course of existing diseases (Journal of American Medical Association, 12 June 1991).
However, since the publication of our two earlier reports on the dangers of amalgam fillings (WDDTY vol 1 no 7 and vol 3 no 3) and also our Dental Handbook, many reputable scientists have discovered further devastating proof that amalgam fillings can make you, your dentist and even your unborn babies ill.
Although past studies have shown that dentists have high concentration of body mercury and and double the number of brain tumours (British Journal of Industrial Medicine, 1991; 48: 729-34), new evidence demonstrates that amalgam causes subtle brain damage as well. Several years ago, an assessment of the neurological functions of dentists in Singapore found they performed less well than a similar group that hadn't had regular amalgam exposure, although they did just as well on intelligence tests. The higher the exposure to mercury, the worse the performance on the neurological tests (British Journal of Industrial Medicine, 1992; 49: 782-90, British Medical Journal, November 28, 1992).
Dr Diana Echeverria, a neuro-toxicologist at the University of Washington in America also tested American dentists to see whether they show signs of mercury poisoning. Her study found subtle losses of manual dexterity and concentration both evidence of central nervous system disorders.
The party line of the American Dental Association and the British Dental Association is that the mercury in amalgam fillings becomes inert, or "locked in", when mixed with the other metals and placed in the mouth. But numerous researchers have proved not only that mercury vapours are continuously released from the fillings, but that it also corrodes in the mouth that is, rusts, as the metallic ions and vapour form on the amalgam surface once it comes into contact with heat, saliva and such elements as fluoride or large gold fillings. Although most of these products get excreted, about 10 per cent accumulate in the various organs and tissues of the body, according to researchers at the University of Calgary in Canada.
Professor J V Masi of Western New England College in Springfield, Massachusetts, who has studied this issue in detail, discovered that all metals used as restorative dental materials are capable of corroding. The five metals contained in amalgam can combine to produce some 16 different corrosion products, all floating around in the body to unknown effect.
Although much of the evidence about mercury has a element of speculation, there is growing proof that this released mercury settles in tissues in the body. Dr Murray J Vimy, clinical associate professor of the Department of Medicine, plus numerous other medical researchers from the Departments of Radiology, Medicine and Medical Physiology at the University of Calgary in Canada have spent more than a decade examining the effects of amalgam fillings on sheep, monkeys and, more recently, humans. Their published evidence conclusively proves that mercury from amalgam fillings migrates to tissue in the body the oral cavity, the lungs and the gastrointestinal (GI) tract, causing a type of "timed released poisoning", as Vimy has called it.
Vimy's animal studies, which were met by ridicule within the dental community, have been vindicated by the work of Professor H Vasken Aposhian, head of the Molecular and Cellular Biology Department of the University of Arizona in Tucson. Aposhian and his team graded the amalgam filling content of human volunteers, from which they were given an amalgam score. The study participants were then given a salt of 2, 3-dimercaptopropane 1-sulfonic acid (DMPS), a chelating agent which binds to mercury and removes it from the body through urine. An analysis of the results showed a positive correlation between the amount of amalgam in the teeth and the amount of amalgam in the body. Aposhian's team was also able to show that two thirds of the mercury excreted in the urine of those study participants with dental amalgam came from their fillings (FASEB Journal, 1992; 6: 2472-6; Clinical Toxicology, 1992; 30 (4): 505-28).
A number of new studies and clinical observations imply a relationship between amalgam and the onset of some diseases.
Earlier studies have showed a relationship between mercury poisoning from amalgam fillings and multiple sclerosis (see the WDDTY Dental Handbook). But connections are now being made with other sclerosing diseases, like amyotrophic lateral sclerosis, the wasting disease which afflicts Dr Stephen Hawking, the cosmologist.
Recently, a Swedish journal documented a case of a patient which numerous neurological problems diagnosed in 1984 with ALS, thought to be invariably fatal. The dentist, who recognized many symptoms as similar to those of mercury poisoning, suggested that the patient have her copious amalgam fillings replaced, particularly as she could date her neurological problems from the placement of the fillings. Six weeks after the fillings were replaced, the patient was able to walk up stairs without experiencing back pain. Four months later, she returned to the same University Hospital at Umea, Sweden, which had diagnosed her illness, for a week long follow up investigation.
The following notation was placed in her record: "The neurological status is completely without comment. Hence the patient does not show any motor neuron disease of type ALS. She has been informed that she is in neurological respect fully healthy." The hospital concluded that the problem had been due to mercury in the spinal cord. Nine years hence, the patient is still in good health (Int J of Risk Safety Medicine, 1994; 4: 229-236).
New evidence on humans shows that mercury fillings in pregnant women may also affect the growing fetus. In 1989 the University of Calgary Medical School published evidence that within three days of placing amalgam fillings in pregnant sheep, mercury showed up in the blood, pituitary glands, liver, kidney and placenta of their babies. By 33 days (around the time of birth), most fetal tissue had higher levels of mercury than that of the mothers. During nursing, the mother sheep were found to have eight times as much mercury in their milk as in their blood (American J Physiology, 1990; 258: R939-945).
More recently, Professor Gustav Drasch, a forensic toxicologist and his colleagues at the Institut fur Rechtsmedicine in Munich, examined the brains, liver and kidneys of dead human babies and fetuses aborted for medical reasons. They found these levels correlated significantly with the number of amalgam fillings in their mothers. Furthermore, children accumulated mercury in their kidneys apparently from the mother's amalgams to a similar extent as adults do from their own fillings. As most of the children weren't breastfed or fed for only a short period, the researchers concluded that the mercury must have crossed the placenta (European Journal of Pediatrics, 1994; 153: 607-10).
There's also evidence that silver fillings may affect fertility. A group of German researchers gave women with hormonal irregularities the chelating agent DMPS to remove mercury from the body, while also examining their blood for evidence of excessive levels of various pesticides. By far the most common problem was mercury contamination, which again correlated significantly with the number of the woman's fillings and the release of mercury while chewing. Women with hormonal disorders excreted the most mercury after being given DMPS ( Zentralbatt fur GynSkologie, 1992; 14: 593-602).
In another study conducted by some of the same German researchers in Heidelberg, Germany, of 132 women suffering from unexplained hair loss where other therapies had been unsuccessful, 49 per cent showed evidence (with DMPS test) of elevated mercury, and in 68 per cent the condition disappeared once they'd had their fillings removed (Klinisches Labor, 1992; 38: 469-76).
Many dentists like Hal Huggins and Jack Levenson claim a wealth of cases where their patients suffering from food or environmental ailments improved in some way once their fillings were removed.
In a consolidated report of six separate studies of patients who had their amalgam fillings replaced, nearly all the 1600 participants reported cure or improvement of 31 types of conditions.
The studies from four countries showed that an aggregate of 89 per cent of those who said they suffered from allergies reported an improvement. Of gastrointestinal symptoms, patients reported improvement or cure in bloating (88 per cent), general gastrointestinal problems (83 per cent) and urinary tract problems (76 per cent). Of those with headaches, 87 per cent cured or improved their migraines. Significantly, three quarters of those with multiple sclerosis said they were better or cured.
If this data were extrapolated to all people in the US with silver fillings, 17.4 million would have their allergies improve or disappear simply by having their mercury dental fillings exchanged for non-mercury ones (Bio-Probe, March 1993).
One Swedish patient had suffered with allergic problems, including eczema, from birth. At five she developed severe asthma, and had to take daily medication. During the whole of her adolescence she was often hospitalized. She also suffered from severe headaches and double vision. At three, the girl had had her first amalgam filling; she was ultimately to have seven fillings over 11 surfaces. On examining her history, researchers discovered that her asthma had come on following the placement of two deep fillings. They also realized that her mother had received a large amalgam filling during her pregnancy.
The girl and her mother consented to have all the amalgam fillings removed. Six weeks after the procedure was completed, her eczema began to disappear and she no longer required asthma medication. Seven months later, both conditions completely cleared up, and stayed clear for the eight years she was followed up (Int J of Risk Safety Medicine, 1994; 4: 229-236).
Even though there are many success stories, Jack Levenson and Hal Huggins caution that unlike their MS patients, 85 per cent of whom improve, only 60 per cent of their "environmentally ill" patients get better, suggesting that mercury is only one of many contributory factors.
Increasing evidence shows that mercury, rather than aluminium, is the highest trace element found in the brains of Alzheimer's disease victims (see WDDTY vol 5 no 2). Researchers at the University of Kentucky have showed that the highest trace element in the brains of autopsied AD patients consistently was mercury (Brain Research, 1990, 553: 125-31), and that minute doses of mercury in the brain produce identical changes to those seen in AD (FASEB 75th Annual Meeting, Atlanta Georgia, 21-25 April 1991. Abstract 493).
The latest research published by Vimy and his team at the University of Calgary Medical School used rats to show that inorganic mercury compound markedly inhibited tubulin levels, a protein which is needed for the healthy formation of neurofibrils, or connective nerve tissue. Most significantly, the rat brain concentrations of mercury were similar to those recorded in monkeys 28 days after placement of dental amalgam fillings (Journal of Neurochemistry, 1994; 62: 2049-52).
Even if the dental associations in Britain and America have chosen to ignore the mounting data suggesting serious potential problems from amalgam, companies which manufacture amalgam (and could be most open to liability claims) recently had to take the warning signs seriously. Under California law, Proposition 65 aims to protect people from being unwittingly exposed to chemicals known to cause cancer or birth defects. Any work environment containing materials with such potential must carry a warning.
The Environmental Law Foundation decided to test this by taking one of the biggest manufacturers of dental amalgam to court on this issue. The court ruled in favour of the Foundation, and Jeneric became the first company to issue health warnings on its product, in the form of an alert to dentists, dental staff and patients in California about the potential dangers of birth defects from exposure to mercury.
Jeneric also agreed to stop selling silver mercury fillings to dentists who fail to put up the warning.
However, afterward, 10 other dental amalgam manufacturers banded together and challenged the ruling. A federal court judge decision overturned the earlier one, on the grounds that the regulatory authority for amalgam was not Proposition 65, but the US Food and Drug Administration, which of course has ruled that mercury fillings are safe.
"For every one step forward," says Dr Vimy, "we take 10 steps back."