Deadly Mercury - How It Became Your Dentist's Darling
by Val Valerian

Exposure to mercury from "silver" dental fillings is slowly poisoning mil-lions of Americans each year. In fact, chronic mercury toxicity from such fillings ranks among our most serious public health problems.

The modern dental amalgam, widely misnamed "silver" and used in fillings for more than 180 years, now accounts for 79-80 percent of all dental restorations.1 In truth, however, it contains only about 35 percent silver by weight, compared to 50 percent mercury (with 13 percent tin, and small amounts of copper and zinc).2

Citing the silver-mercury ratio, Murray Vimy, professor in the Department of Medicine at the University of Calgary (Canada), notes that average amalgam fillings have a mercury mass of 750-1,000 milligrams (mg) and should more properly be called mercury fillings. They have a functional life of about 7-9 years, after which they are usually replaced with another one made of the same material.3,4

Mercury is more toxic than lead or even arsenic. Considering the mountains of scientific information that have accumulated over the last 70 years, which clearly show the poisonous effects of mercury, using it today in dentistry is simply criminal. Yet each year worldwide, hundreds of tons of this toxic material are placed into patients' teeth, while some finds its way from dental offices into sewage and refuse systems, to poison the environment instead of the patients.

The American Dental Association (ADA) and government scientists know mercury's potential and actual harm, yet continue to promote its use. They thus make a direct, if covert assault on America's health while producing large profits for themselves and their special interest group. Appropriately, such crimes are punishable by death under the Crime Bill of 1994 and United Nations rules concerning genocide.5

Within the dental profession, the issue of mercury-filling safety has recurred periodically. Introduced in 1812 by British chemist Joseph Bell, the "silver paste"—a combination of old silver coins and mercury—became fashionable for tooth restoration. Since the coins were not pure silver, the material often expanded, fracturing teeth and/or giving patients a "high bite."

When it was first introduced in the United States (in 1833 in New York), dentists rebelled. They refused to use the "silver" because it caused immediate symptoms of mercury poisoning. Within the first 10 years most dentists denounced its poor filling qualities and toxic nature, forming the American Society of Dental Surgeons in 1840 to declare mercury usage malpractice. The society mandated that its members sign an oath not to use materials containing mercury.

Nevertheless, amalgam increased in popularity, particularly among poorly-educated practitioners; it was cheaper than gold—the standard until then—giving the renegades an economic edge over their colleagues who demanded higher quality. (In those days many nonprofessionals, including itinerant peddlers, were filling teeth for the pioneer population also.) Besides, amalgam fillings were user-friendly—for the dentist, not the patient—and durable in the mouth.

By 1856, the anti-amalgam society had lost so many members that it had to disband, while wealthy businessmen (not dentists) founded a new group to push the toxic material: the ADA. For a time the debate was dead.


The poison had won; the patients had lost.6,7


In the 1920s another controversy erupted after Dr. Alfred Stock, a German chemistry professor, published articles and letters attacking mercury fillings for their possible toxic effects. By 1935, Stock's research proved that some of the mercury vapor coming from dental amalgams enters the nose, is absorbed by the mucosa and passes rapidly into the brain: It was found in the olfactory lobe and in the pineal gland. After a while, however, the furor surrounding Stock's findings also died down.

Now, nearly 150 years after its founding—and in the midst of its third "amalgam war"—the ADA is trying to kill the debate for all time: It has amended its code of ethics to condemn the removal of serviceable mercury fillings as unethical, if the reason is to eliminate a toxic material from the body and if the recommendation is made solely by the dentist.8

According to Professor Vimy, the ADA considers a dentist ethical if he places the poisonous substance and recommends its safety. However, if he suggests that mercury fillings are potentially harmful or that exposure to unnecessary mercury can be, he is acting unethically. Serviceable mercury fillings can be "ethically" removed if clone for aesthetic reasons, at the request of the patient (without prompting) or a medical doctor.

In 1967, the inaugural issue of Environmental Research magazine featured "Mercury-Blood Interaction and Mercury Uptake by the Brain After Exposure," the research of L. Magos. His experiments with mice indicated that inhaled mercury reaches the brain.

Mercury amalgam continuously gives off vapor, and, inhaled, it has an incredibly high absorption rate—between 70 and 100 percent! Once in the brain, mercury oxidizes into its elemental form. Then the blood-brain barrier, designed to protect the brain from foreign substances in the blood, works against its own purpose, preventing the removal of the toxic metal from the brain.

Nonetheless, in 1976, the FDA pronounced its "acceptance" of mercury amalgam, since "it had been in use since 1840." It was added to the Generally Recognized As Safe (GRAS) list of pre-1930 drugs.

In 1979, perhaps as a reaction to the FDA ruling, research began appearing which documented that mercury vapor is constantly released from fillings, especially when they are stimulated by chewing, brushing or temperature shifts (such as drinking a hot liquid). Every time someone with amalgam fillings eats or brushes his teeth, the leaching of mercury into the body peaks. Afterwards, it takes almost 90 minutes for the vaporization rate to decline to its previous level.9

Also, the greater the number of fillings and the larger the chewing-surface area they occupy, the greater the toxic exposure.10, 11 Since hot liquids also increase vaporizing, individuals with amalgam fillings who frequently drink tea or coffee run a higher risk of mercury-related pathologies.

The average person, with eight biting-surface mercury fillings, is exposed to a daily-dose uptake of about 10 mcg (micrograms) of mercury from his fillings.12 Some individuals may have daily doses 10 times higher (100 mcg) because of factors that exacerbate mercury vaporization, such as more frequent eating, chronic gum chewing, chronic tooth grinding (usually during sleep), chewing patterns, consumption of hot or acidic foods and drinks, and mouth acidity.13

Furthermore, Professor Vimy asserts the concentration of mercury in the brain correlates with the number of fillings present. In 1980, the World Health Organization (WHO) admitted,

"The most hazardous forms of mercury to human health are elemental mercury vapor and the short-chain alkyl-mercurials."14

By 1984, autopsy studies were published that demonstrated that the amount of mercury found in brain and kidney tissue directly relates to the number of mercury amalgam filings in the teeth. Research at the University of Calgary School of Medicine demonstrated that mercury from dental fillings could be found in the blood and tissues of pregnant mothers and their babies within a few days of insertion.

The Biological Effects of Mercury Amalgam: Scientific Facts and References

  1. Mercury penetrates the blood-brain barrier which protects the brain, and as little as one part per million [ppm] can impair this barrier, permitting entry of substances in the blood that would otherwise be excluded.
    —Changand Hartman, 1972; Chang and Burkholder, 1974

  2. Mercury exposure from amalgams leads to interference with brain catecholamine reactivity levels, has a pronounced effect on the human endocrine system and accumulates in both the thyroid and pituitary glands reducing production of important hormones.
    —Carmignani, Finelli and Boscolo, 1983; Kosta et al., 1975; Trakhtenberg, 1974.

  3. Mercury inhibits the synaptic uptake of neurotransmitters in the brain and can produce subsequent development of Parkinson's disease.
    —Ohlson and Hogstedt, "Parkinson's Disease and Occupational Exposure to Organic Solvents, Agricultural Chemicals and Mercury," Scandinavian Journal of Work Environment Health, 7, no. 4:252-256, 1981.

  4. Mercury is nephrotoxic (toxic to the kidneys) and causes pathological damage.
    —Nicholson et al., "Cadmium and Mercury Nephrotoxicity," Nature, 304:633, 1983.

  5. Mercury has an effect on the fetal nervous system, even at levels far below that considered to be toxic in adults. Background levels of mercury in mothers correlate with incidence of fetal birth defects and still births.
    —Reuhl and Chang, 1979;Clarkson et al., 1981; Marsh et al, 1980; Tejning 1968; W.D. Kuntz, R.M. Pitkin, A.W. Bostrum, and M.S. Hughes, The American Journal of Obstetrics and Gynecology, 143, no. 4:440-443, 1982.

  6. Chronic exposure to mercury may cause an excess of serum proteins in the urine which may progress to nephrotic syndrome and peculiar susceptibility to infections that break into and modify the course of any pre-existing disease.
    —Friberg et al. (1953), "Kidney Injury After Chronic Exposure to Inorganic Mercury," Archives of Environmental Health, 15:64, 1967; Kazantis et al., "Albuminuria and the Nephrotic Syndrome Following Exposure to Mercury," Quarterly Journal of Medicine, 31:403-418, 1962; Joselow and Goldwater, "Absorption and Excretion of Mercury in Man and Mercury Content of 'Normal' Human Tissues," Archives of Environmental Health, 15:64, 1967.

  7. Mercury fillings can contribute to a higher level of mercury in the blood and can affect the functioning of the heart, change the vascular response to norepinephrine and potassium chloride and block the entry of calcium ions into the cytoplasm.
    —Abraham et al., "The Effect of Dental Amalgam Restorations on Blood Mercury Levels," Journal of Dental Research, 63, no. 1:71-73, 1984; Kuntz et al., "Maternal and Cord Blood Background Mercury Levels: A Longitudinal Surveillance," American Journal of Obstetrics and Gynecology, 143, no.4:440-443, 1982; Joselow et al., 1972; Mantyla and Wright, 1976: Trakhtenberg, 1968; Oka et al., 1979.

  8. The effect of mercury on the nervous system selectively inhibits protein and amino-acid absorption into brain tissue.
    —Yoshino et al., 1966; Steinwall, 1969; Steinwall and Snyder, 1969; Cavanagh and Chen, 1971.

  9. Mercury induces the thyroid gland to absorb an increasing amount of nuclear radiation from the environment.
    —Trakhtenberg, 1974.

  10. Mercury has a distinct effect on the human immune sys-tem, especially the white blood cells. Mercury ions have been observed to cause chromosomal aberrations and alter the cellular genetic code. Mercury has the ability to induce chromosomal breakage, alter cellular mitosis, cause a drop in T-cell production and kill white blood cells.
    —Vershaeve et al., 1976;Popescu et al., 1979; Skerfving et al.,1970, 1974; Fiskesjo, 1970.

  11. Mercury can impair the adrenal and testicular steroid hormone secretions, causing intolerance for stress and decreased sexual ability. In rats, it causes subnormal fertility and sperm production.
    —Burton and Meikle, 1980; Khera,1973;Stoewsandetal.,1971;LeeandDixon,1975; ThaxtonandParkhurst,1973.

  12. Mercury in the body can produce contact dermatitis and reduced function of the adrenal glands (Addison's disease), producing progressive anemia, low blood pressure, diarrhea and digestive disturbances.

  13. Mercury in the human body can contribute to intelligence disturbances, speech difficulties, limb deformity and hyperkinesia (hyperactivity resulting from brain damage). Abnormally small heads and retardation were present in 60 percent of cases.
    —Amin-Zaki and Clarkson, et al.,1979.


As the existence of the ADA has gradually become integrated into the public's awareness, the perception has grown up that its statements represent scientific truth. The association and its members know that a conditioned and ignorant public will rarely question any statement it makes. Thus, when it issues false statements that jeopardize public health, such as recommending that deadly toxins be placed in the body, it is party to a criminal act.


Having third-party dentists do the dirty deeds does not excuse the association, especially since its members have spent years and much money studying in ADA-approved schools, and anyone who bucks the system risks his license, his income and his career.


This constitutes extortion and racketeering by the ADA, punishable under the RICO Act.15


  • 1990—On December 16, CBS's 60 Minutes did a major story on the amalgam issue that generated the second-highest response for additional information in the history of the program. Most viewers thought it would produce a change in the system. Instead, the ADA launched a vast campaign to counter the knowledge 60 Minutes hadriven the public.

    First, the ADA and "responsible" government agencies invested huge sums of money: They sent special letters and news releases to every dentist in the United States discrediting the scientific information presented on the program and assuring the dentists that amalgam had been used for 150 years so it must be safe. They also sent press releases to all the major media and even created a special program for dentists entitled "What To Tell Your Patients When They Ask About Amalgam."

    Also appearing in 1990 was the first controlled research on the effects of amalgam implants. It cited significant effects of mercury amalgam on various tissues and organs in experiments with monkeys and sheep.

  • 1991—Sweden banned the use of mercury amalgam implants. In March, the FDA recommended "further studies," and consumer groups and legislators began introducing informed consent legislation whereby dentists would be required to inform patients of the content of amalgam fillings (implants) and the potentially harmful effects of mercury.

    In May, a medical research team at the University of Kentucky established "a probable relationship of mercury exposure from mercury-amalgam fillings to both Alzheimer's disease and cardiovascular disease." University of Georgia microbiologists determined that mercury from fillings inhibits the effectiveness of antibiotics.

    The WHO reported that exposure to mercury from amalgams is higher than that of other environmental sources and that each amalgam filling releases from three to seventeen micrograms of mercury daily during eating alone. The WHO audited all available scientific data on the subject and concluded that mercury from dental fillings is the greatest source of human exposure, exceeding intake from fish by about 200 percent.

  • 1993—The International Academy of Oral Medicine and Toxicology (IAOMT) developed a certification program for biocompatible dentistry [using materials compatible with each patient's body chemistry]. Dentists certified by the IAOMT will have "demonstrated proficiency in replacing amalgams safely and properly."

    Swedish researchers discovered that gastrointestinal function improves after amalgam is removed. A citizens' petition requesting a ban on the use of amalgams was filed with the FDA.

    The State of California passed a law requiring the Board of Dental Examiners to develop, distribute and update a fact sheet describing and comparing the risks and efficacy of the various types of dental restorative materials. Prior to this, a dentist risked losing his/her license for giving such detailed information to a patient. Presenting both sides of the dental mercury issue to a patient was considered unethical!

  • 1994—In January, the government of Ontario demanded a probe of mercury dental fillings. In February, Sweden announced a total ban on the use of mercury amalgam fillings.


On July 11, 1994, the British BBC-1 documentary program Panorama focused on the amalgam controversy. Dr. Lars Friberg, chief advisor to the WHO on metals poisoning, told Panorama,

"The use of mercury in dental fillings is not safe and should be avoided."

The program also reported on new scientific research which demonstrated clear links between the mercury released from dental fillings and serious illness, including Alzheimer's disease.

Dr. Friberg told Panorama that he "did not know why" the British Dental Association considers mercury levels in amalgam "safe" and that he thought, "They are wrong." He was concerned particularly about deposition of mercury from fillings into the brains of children.

According to Dr. Friberg,

[W]e know that children are especially vulnerable to the amalgam. We know that it takes a few years after birth until the brain is developed, and we know the brains in children are much more sensitive than those of adults. I think that you should try to avoid the implantation of toxic metals in the mouth. There is no safe level of mercury, and no one has actually shown that there is a safe level. I say mercury is a very toxic sub-stance. I would like to avoid it as far as possible.

Panorama investigated a number of new, independent studies, some unpublished, which point inexorably towards the health risks of amalgam fillings. The first is a new study by Dr. Boyd Haley, professor of bio-chemistry at the University of Kentucky. He discovered that small quantities of mercury from amalgams can produce changes in the brain identical to those caused by Alzheimer's disease. Mercury inhibits the efficiency of tubulin, a protein vital to brain cells.


According to Dr. Haley:

To the best that we can determine with these experiments, mercury is a time bomb in the brain. We need to have an effect—if it's not bothering someone when they are young, especially when they age, it could turn into something quite disastrous. I still have one amalgam filling. When I had the others replaced, I had them replaced with non-amalgam fillings. I would not make the statement that mercury causes Alzheimer's disease, hut there is no doubt in my mind that low levels of mercury, pre-sent in the brain, could cause normal cell death that could lead to a dementia which would be similar to Alzheimer's disease.

Panorama also reported on the unique, ongoing study of a group of nuns by Dr. William Markesbery, professor of pathology and neurology and director of the Sanders Brown Center for Aging at the University of Kentucky.


He is investigating the link between mercury and Alzheimer's disease and told Panorama:

Mercury is a toxic substance. It is a neurotoxin—that is to say it causes nerve cells to degenerate if there is enough mercury present in the brain. The major problem in Alzheimer's disease is the degeneration of nerve cells. It is possible that mercury could add to the degeneration of nerve cells—to the death of nerve cells.

The reaction of the British Dental Association (BDA) to the 1994 Panorama program was predictable: It told Panorama it was unaware of the work of Haley and also unaware of the work of Professor Aposhian at the University of Arizona who discovered that 66 percent of the mercury deposits in the body come from fillings. In fact, John Hunt, chief executive of the BDA, told Panorama, "Amalgam is safe."


The BDA fact sheet available to dentists states,

"The scientific evidence available to the BDA does not justify banning the use of amalgam in young children."

Said Hunt,

"I've treated my children with amalgam and have no doubt that when they have their own children, they will do the same."

Asked about any link between Alzheimer's and mercury, he added:

As far as I know, there is no association with mercury and Alzheimer's. We rely on expert advice. There is no evidence to suggest that merely because mercury is found in the kidneys of the fetus and young children, that it is a hazard to health. I don't see why we should necessarily worry the population at large if there are no proven arguments one way or another.


The fact that it is there and it is detectable doesn't mean to say that it's potentially doing any damage. You can probably find a whole lot of substances in the brain that perhaps should not be there.

Special thanks to Professor Murray Vimy for several of the above references and to the Dental Amalgam Mercury Syndrome (DAMS) consumer advocacy group. For more information contact DAMS at (800) 311-6265.


  1. J.G. Baurer and H.A. First, California Dental Association Journal, 10:47-61, 1982.

  2. E.W. Skinner and R.W Phillips, The Science of Dental Materials, 6th ed. (Philadelphia: W.B. Saundets Co., 1969), pp. 303, 332.

  3. N. Paterson, British Dental Journal, 157:23-25, 1984.

  4. R.W. Phillips, et al., Journal of Prosthetic Dentistry, 55:736-772, 1986.

  5. The United States is exempt from the U.N. Genocide Treaty of March 1988, as it signed on the condition that "no nation shall sit in judgment of the United States." Technically, any form of genocidal activity is legal in the United States under U.N. mandates.

  6. American Academy of Dental Science, A History of Dental and Oral Science in America (Philadelphia: Samuel White, 1876).

  7. D.K. Bremmer, The Story of Dentistry, rev. 3rd ed. (Brooklyn: Dental Items of Interest Publishing, 1954).

  8. "Representation of Care and Fees," Principles of Ethics and Code of Professional Conduct (American Dental Association, 211 E. Chicago Ave., Chicago, IL 60611).

  9. J.J. Vimy and F.L. Lorscheider, Journal of Dental Restorations, 64:1072-1075, 1985.

  10. Ibid. pp. 1069-1071.

  11. Ibid. pp. 1072-1075.

  12. J.J. Vimy and F.L. Lorscheider, Journal of Trace Element Experimental Medicine, 3:111-123, 1990.

  13. Vimy and Lorscheider, Dental Restorations, pp. 1072-1075.

  14. World Health Organization, "Recommended Health-based Limits in Occupational Exposure to Heavy Metals," 1980.

  15. Racketeer Influenced and Corrupt Organizations Act (18 USC 1961 et seq.; 84 Stat 922).

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