I: The Danger in Our Mouths

The use of mercury in dental amalgam fillings has been an accepted practice in the United States for more than a hundred years. So it should come as no surprise that most people assume the silvery-looking fill-ings in their mouths are safe and nontoxic, posing no risk to their health. But is this assumption well founded? An analysis of the scientific evidence on mercury can only lead to a resounding “no.”

Mercury is a toxic heavy metal that can have disastrous health effects. Research shows that mercury is associated with dis-orders such as multiple sclerosis, Alzheim-er’s disease, depression and reduced im-mune functioning. Mercury exposure also presents a risk to fetuses in mothers who have amalgam fillings. California recog-nized this risk in November 2000 when it became the first state to require dentists to inform their patients that amalgam fill-ings may cause birth defects.

It is of interest that the studies prov-ing mercury’s toxicity often come from the journals of conventional dentistry and medicine. Even so, orthodox dentistry con-tinues to assure us that the mercury in our mouths is safe. This disconnect between our long-standing assumption that mer-cury amalgams are nontoxic and the evi-dence showing otherwise reminds us of an important principle: What has been ac-cepted as true is not always so scientifically.

The Amalgam Controversy

Dental amalgam is not the first sup-posedly “safe” product to generate contro-versy. Over the past few decades Americans have been besieged by a series of man-made health epidemics, and in each case the gov-

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ernment and its watchdog agencies rou-tinely assured us that a danger did not ex-ist. Because they would not allow harmful foods, chemicals or drugs on the market, the reasoning went, the very fact that the prod-ucts were in use assured us of their safety.

When overwhelming evidence proved the contrary, government and industry only begrudgingly removed these products from shelves. The epidemics in question? Diethylstilbesterol, a medication that harmed millions of Americans; Oraflex, an anti-arthritic drug; DDT, a pesticide; and the Dalkon shield, to name just a few of more than 200 such items that received an official stamp of approval over the years.

Now the battle line has been drawn over the mercury amalgam used in dental fillings. On one side of the battle are the scientists, holistic dentists and health ac-tivists who believe mercury amalgams are a biological time bomb ticking away in our mouths. They point to scientific evidence showing that chronic mercury exposure from dental fillings puts most people at risk of serious health disorders.

On the other side is the dental estab-lishment, led by the American Dental Asso-ciation, which claims that mercury amalgam has adverse effects only on those people who are hypersensitive to it. The ADA pegs this group at 1% of the population (a figure dis-puted by research). For the rest of us, it says, amalgams pose absolutely no harm.

The ADA has yet to offer scientific proof of mercury’s safety, however, leading health advocates to call for a ban on its use. The Toxic Element Research Foundation (TERF) claims that the cumulative effects of mercury amalgam poisoning make it one of the most insidious health hazards fac-ing Americans today.

“The true impact of amalgam poison-ing is similar to that of the Chernobyl trag-edy,” states the organization. “The magni-tude of the crisis is not the few who have died from massive exposure, but rather it is the millions whose health will be eroded by the ongoing, small-dose poisoning.”¹

A somewhat bizarre variant of this explanation is cited by Dr. Hal Huggins, D.D.S., in his recent expose of the amalgam controversy, “Integrity vs. Intimidation.”16 In the ADA’s Guide to Dental Materials and Devices, the reader is informed that amal-gam does release small amounts of mer-cury, but that “this evaporation stops as soon as the filling is coated by saliva.”¹⁷

“Most scientists from physics chemis-try and toxicology would tell you,” Huggins comments, “that when multiple metals are warmed up to mouth temperature and coated with an electrolyte like saliva, you have a perfect condition to form a battery. In this case, the efflux from this filling-battery would be mercury, either as vapor, inorganic mercury…or methylmercury.”¹⁸

The assurances provided by the ADA have no basis in scientific fact. To the con-trary, they frequently fly in the face of sci-entific reality. Speaking of the ADA’s claim that mercury combines with other metals in dental amalgam to form a biologically inactive substance, Dr. Douglas Swartzendruber, chairman and former dean of the biology department at the Univer-sity of Colorado in Colorado Springs, said, “They must have discovered alchemy.”¹⁹ Existing scientific evidence strongly sup-ports the conclusion that mercury amal-gam fillings are a danger to your health.

“How could mercury be completely harmless when put into a patient’s mouth?” asks Dr. Boyd Haley, professor and chair of the department of chemistry at the Univer-sity of Kentucky. “I think the situation would make a great Gilbert and Sullivan musical,” Haley notes. “It is absolute silli-ness for the Environmental Protection Agency (EPA) and OSHA to say that mer-cury before going in and after coming out of mouth is totally toxic, but inside the mouth is absolutely safe.”²⁰

Indeed, there is no proof that the vola-tile substance transforms into an inert in-gredient. Research shows that amalgams expose people to mercury vapors continu-ously, especially after fillings are stimulated by chewing, brushing or heat.

“The ADA claims that when mixed with other metals the amalgam fillings form a biologically inactive substance,” says Dr. Tano Lucero, a former research chem-ist and industrial hygienist for OSHA who later became president of Bio-Ethics Medi-cal Center in Scottsdale, Arizona. “This is simply not true. Is elemental mercury es-caping from filling material? The answer is an absolute YES!... Having worked for OSHA for 17 years, never have I witnessed any-thing of the magnitude of resistance in acknowledging the danger of toxicity in silver amalgams as by the ADA.”²¹

The Dangers of Mercury

Increasingly, the ADA’s pro-mercury position runs counter to scientific evidence proving amalgam’s dangers. As far back as 1980 the World Health Organization (WHO) identified elemental mercury vapor (the form leached by amalgam) as one of the two most hazardous types of mercury to human health. Research has shown that chronic exposure to small amounts of mer-cury can affect everything from the nerv-ous and immune systems to brain and kid-ney functioning.

The peer-reviewed scientific literature reveals a number of disturbing facts about dental amalgam, according to a review con-ducted by the Australasian Society of Oral Medicine and Toxicology (ASOMAT), a nonprofit professional organization of den-tists and doctors that promotes concepts of biocompatible dentistry. ASOMAT’s analysis found that the mercury contained in dental amalgams is continuously re-leased from fillings and almost totally ab-sorbed, that it accumulates in tissues throughout the body, and that the very toxic metal interferes with a variety of physiological systems. Further, the physi-ological effects and health changes that occur can be demonstrated through the placement and removal of amalgam, and the dental profession itself has shown evi-dence of health problems related to mer-cury exposure.²²

“The disease symptoms are insidious and overlap with the symptoms of many other diseases,” points out Dr. Alfred V. Zamm, environmental medicine pioneer and author of Why Your House May En-danger Your Health. “Mercury poisoning is the greatest masquerader of our time. Den-tists are not in a position to see the cause and effect relationship of the insertion of mercury and the development of illness three to 10 years later. Even the patient himself does not connect the illness to the original dental process.”³²

II: How Mercury Escapes into Body

Although a diagnosis itself may be elu-sive, the scientific research proving mercu-ry’s toxicity has been piling up for years. The realities of mercury poisoning are hard to ignore when numerous studies show that mercury can leach from amalgams, be ab-sorbed into tissues, travel to the brain and wreak havoc in the body. Consider the fol-lowing research:

Exposure from Amalgam Fillings

The ADA has claimed that people are exposed to more mercury from fish than from dental amalgams, a statement chal-lenged by the International Academy of Oral Medicine and Toxicology because the scientific evidence proves otherwise. As the Academy states, “Autopsies of people with fillings confirm that the amount of expo-sure to dietary mercury is apparently much less than that from dental amalgam mer-cury. Authorities in the field of metal toxi-cology have concluded that this chronic exposure from dental fillings makes the predominant contribution of human expo-sure to mercury.”³³

Numerous studies support the finding that amalgam fillings are the main source of mercury exposure in the general popu-lation. Perhaps the earliest of these is a 1991 report produced by the World Health Or-ganization in conjunction with the United Nations Environment Programme and the International Labor Organization. This re-port states very explicitly that mercury dental fillings are the principal source of mercury and mercuric compound intake and retention among the general popula-tion not occupationally exposed to mer-cury.³⁴

A 1995 review by Drs. Lorscheider and Vimy and Anne O. Summers, a biochemist, concludes that “Medical research has dem-onstrated that mercury from dental amal-gams is continuously released as vapor into mouth air. Animal and human experiments demonstrate that the uptake, tissue distri-bution, and excretion of amalgam mercury is significant, and that dental amalgam is the major contributing source to mercury body burden in humans.”³⁵

A 1994 study of patients undergoing total amalgam removal found that expo-sure from amalgam fillings exceeds expo-sure from food, air and beverages.³⁶ A 1992 experiment involving volunteers with and without amalgam fillings concluded that two-thirds of the mercury excreted in the urine of those with dental amalgams is derived originally from the mercury vapor released from their amalgams.³⁷

Leaching from Fillings

According to organized dentistry, amalgams do not pose a long-term threat because the mercury becomes inert after a filling has set for several days. But a number of studies prove that mercury continues to leach from fillings due to the ongoing de-terioration of the amalgam.

Factors leading to corrosion include the physical stress of chewing, the acidity and temperature of foods and beverages and the electromagnetic potential of other metals in the mouth. Dental amalgam con-tains not only mercury (52% by weight), but also silver, tin, copper and zinc. Crowns and bridges may contain these elements as well as aluminum, beryllium, gold, iridium and nickel.³⁸ Even the simple act of brushing your teeth can release mercury from amal-gam, according to a 1985 report by J.E. Patterson.³⁹

Mercury’s Route in the Body and Brain

Once an amalgam releases mercury vapor, the inhaled fumes can travel throughout the body and into the brain. The vapor is absorbed into body tissues, oxidized to ionic mercury and finally covalently bound to cell proteins.⁵¹ The mercury fumes also settle on the mucous membrane of the nasal cavity, an especially dangerous location since the mercury is then transported directly to the pituitary gland and the brain.⁵²

In fact, mercury can easily enter brain tissue after crossing the blood-brain bar-rier or latch on to a developing fetus after passing through the placenta. This is espe-cially true of mercury vapor, where 74% to 100% is assimilated.⁵³

Mercury vapor has a particular affin-ity for the pituitary gland, according to Charles Williamson, M.D., co-director of the Toxic Studies Institute in Boca Raton, Florida. This gland is only 2 centimeters away from the oral cavity, just the other side of the cribiform plate—a light, spongy bone in the roof of the nose, between the eyes. Mercury penetrates the cribiform plate via “axonal transport.” “It goes right up the neurons,” Williamson explains.⁵⁴

Dr. Haley of the University of Kentucky adds, “I don’t want to panic people, but I think we have to be realistic. Mercury comes out of amalgams. It gets into our saliva, and we swallow it. The vapors go through the membranes of our mouth to the nasal mucosa and collect in the brain. There’s almost no way that it can’t do that. It’s not safe.”⁵⁵

The link between dental amalgams and the presence of mercury in brain tissue was established in a 1987 study conducted by Dr. David Eggleston of California in conjunction with Dr. Magnus Nylander of Swe-den. The study found a direct correlation between the number of amalgam surfaces and the amount of mercury accumulated in the brains of 83 cadavers. The subjects with five or more amalgams had an aver-age of three times more mercury in the brain than those with no amalgams.⁵⁶

Likewise, autopsies performed at the Karolinska Institute in Sweden, whose board of governors selects the recipient of the Nobel Prize for Medicine, found that people with amalgams had three times more mercury in the brain and nine times more in the kidneys than those with no amalgams. The parts of the brain most vulnerable to mercury amalgam accumu-lation are the occipital lobe cortex, the cer-ebellar cortex and the semilunar ganglion, according to the study.⁵⁷ In a 1996 study conducted at the University of Tubingen in Germany, autopsy of 55 subjects revealed a statistically significant correlation between the number of dental amalgam fillings and the mercury concentration in the occipital lobe cortex.⁵⁸

One of the United States’ leading toxi-cologists, Dr. Louis Chang, also has found a direct connection between dental amal-gams and mercury concentrations in the brain. “Mercury levels tend to be higher in those people that have the amalgams, and mercury levels increase as the number of amalgams increases,” reports Chang, direc-tor of interdisciplinary toxicology and ex-perimental pathology and a professor of pathology, pharmacology and toxicology at the University of Arkansas.⁵⁹

Chang’s observation is borne out by recent research. In 1999 Croatian research-ers studied two experimental groups of rats, one with amalgam fillings placed in their teeth and another fed an amalgam-supple-mented diet. After a two-month exposure to mercury, brain mercury concentration in rats with amalgam fillings was eight times higher than in the controls and two times higher than in rats who ate amalgam-sup-plemented food.⁶⁰ This study clearly eluci-dates the importance of the nose-brain route in mercury assimilation. The inhala-tion of mercury vapor from amalgam fill-ings delivers mercury to the brain even more effectively than eating it.

One look at the effect on fetuses comes from a 1989 study that followed the route of mercury vapor in the bodies of five pregnant sheep. Dr. Vimy, a consultant to the World Health Organization, placed amalgams in the sheep’s molars during the middle of their pregnancy. The researchers then used a ra-dioactive isotope to isolate the amalgam mercury from other sources and trace its course in both fetal and maternal systems.

They noted the following effects after amalgam placement:

• Day 3: Mercury buildup was evident in the maternal and fetal blood, the amni-otic fluid and the maternal urine and feces.

• Day 16: Maternal mercury levels were highest in the kidneys, liver, gastro-intesti-nal tract and thyroid. Fetal levels peaked in the pituitary gland, liver, kidneys and placental cotyledon.

• Day 33: Most fetal tissues of the new-born sheep had higher mercury levels than did the maternal tissues, specifically in the liver, epiphysial bone, bone marrow, bile, blood and brain.

• Day 73: Mercury levels in the mothers’ tissues continued to rise in the kidneys, liver, parotid glands, lungs, pancreas, gastro-intes-tinal tract, adrenal glands, pituitary gland, urine, bile, brain and thyroid gland.

Based on these results, the research-ers concluded not only that the mercury released from fillings accumulates in ma-ternal and fetal tissues, but also that “den-tal amalgam is most probably the major source of chronic mercury exposure in humans.”⁷³

In 1997 parallel studies conducted on sheep and humans found that the place-ment and removal of “silver” tooth fillings in pregnant and lactating humans will sub-ject the fetus and neonate to unnecessary risk of mercury exposure. The authors con-cluded that mercury originating from ma-ternal amalgam tooth fillings transfers across the placenta to the fetus, across the mammary gland into milk ingested by the newborn, and ultimately into neonatal body tissues. In lactating women with aged amalgam fillings, increased mercury excre-tion in breast milk and urine correlated with the number of fillings or mercury vapor concentration levels in mouth air.⁷⁴

Dr. Williamson emphasizes mercury’s effect on the fetal pituitary gland, which affects the development of the endocrine, immune and reproductive systems. “The fetal pituitary gland concentrates mercury,” he says. He notes that mercury decreases the transport of oxygen and essential nu-trients to the fetus and depresses the en-zyme isocitric dehydrogenase. This causes reduced iron uptake and hypothyroidism, learning disabilities and a reduction in IQ. Mercury exposure affects levels of nerve growth factor in the brain, impairs astro-cyte function and causes brain develop-mental imbalances.⁷⁵

“The level of mercury in the tissue of the fetus, newborn and young children is directly proportional to the number of amalgam surfaces in the mother’s mouth,” Williamson says. “Inorganic mercury meth-ylated in the mouth by microorganisms to organic mercury is the most acutely neu-rotoxic form.”⁷⁶

Dr. Williamson believes there will be a public outcry against the use of mercury amalgam when women realize their dental fillings can damage the brains of their un-born babies and result in low IQ, learning and behavioral problems, and autism. He envisions something like the backlash against tobacco or drunken driven.⁷⁷

Children, for their part, are especially vulnerable to the effects of mercury accu-mulation because their bodies are still de-veloping. In 1994 German researchers dis-covered that children with amalgam fillings have fourfold higher urinary concentration of mercury than do children without amal-gams. The researchers also confirmed the correlation between the number and extent of amalgam fillings and the urinary mer-cury concentration.⁷⁸

Alzheimer’s Disease

About a decade ago scientists began to document a connection between mercury and Alzheimer’s disease (AD), a common neurodegenerative disorder that leads to dementia and death. A group led by Dr. William Markesbery, director of the Sand-ers Brown Center on Aging at the Univer-sity of Kentucky, and Dr. William Ehmann autopsied the brains of Alzheimer’s patients and found that their brain tissue had about double the concentration of mercury as that of patients who died of all other causes.⁸⁶ The Alzheimer’s patients’ nucleus basalis of Meynert, a brain area that trans-mits memories and sensations to higher areas of the brain, contained almost four times as much mercury as did the con-trols.⁸⁷

A 1995 animal study by Lorscheider, Vimy and Summers adds further credibil-ity to the Alzheimer’s-mercury connection. It revealed that mercury vapor interacts with brain tubulin and disassembles microtubules that maintain neurite struc-ture. Thus, ionic mercury can alter a neu-rochemical reaction involved with main-taining neuron membrane structure. This results in the formation of “neurofibrillary tangles,” which are a characteristic feature of brain tissue from Alzheimer’s patients.⁸⁸

A later experiment by Lorscheider and Vimy in collaboration with Dr. Haley of the University of Kentucky’s Lucille Markey Cancer Center builds on this discovery. Rats were exposed to carefully controlled dos-ages of mercury vapor mimicking the lev-els found in the mouths of people with a high number of amalgam fillings. The rats deteriorated very quickly, developing brain lesions identical to those found in human Alzheimer’s disease patients.⁸⁹

On the other hand, a study conducted at the College of Dentistry at the Univer-sity of Kentucky found no significant asso-ciation between Alzheimer’s disease and number, surface area or history of having dental amalgams. The researchers, led by Dr. Stanley R. Saxe, a retired professor of periodontics and geriatric dentistry, stud-ied 68 subjects with AD and 33 control subjects without AD to determine mercury levels in multiple brain regions at autopsy and ascertain the subjects’ dental amalgam status and history. The majority were as-sessed while they were alive; some were assessed at autopsy only. The researchers also determined three dental amalgam in-dex scores—Event (placement, repair or removal of amalgam), Location and Time In Mouth—in addition to the numbers of and surface area of occlusal amalgam res-torations. They determined mercury levels in multiple brain regions and performed full neuropathologic evaluations to confirm the normal status of the brain or the pres-ence of AD. In addition to finding no asso-ciation between Alzheimer’s and amalgams, the team found no differences in brain lev-els of mercury between subjects with Alzheimer’s disease and controls.⁹⁰

There is nothing particularly surpris-ing about the results of this study. Studies that fail to show any positive result are common in science. It is important to un-derstand, however, that the failure to find a positive result does not prove that there is no relationship between dental mercury and Alzheimer’s disease. It merely shows that the phenomenon in question was not observable under the conditions of the ex-periment in question.

However, Dr. Saxe offered the follow-ing explanation of his team’s results in a story distributed nationally by PR Newswire on February 5, 1999: “This study demonstrates that dental amalgam is not a major public health risk factor for Alzhe-imer’s disease…. This is the first thorough clinical pathological correlative study of humans to show that mercury in dental amalgam restorations does not appear to be a neurotoxic factor in the development of Alzheimer’s disease.”⁹¹ Saxe’s statements appeared in media all over the country. However, we must ask ourselves how this study failed to find differences in brain lev-els of mercury between subjects with Alzheimer’s disease and controls, a rela-tionship that had been demonstrated in numerous earlier studies?^92-97

Depression and other Emotional Distur-bances

As noted earlier, mercury can go through the roof of the mouth to within less than an inch of the posterior pituitary gland, which has much to do with our out-look on life. When these glands do not function properly, depression may result.

In a study conducted by Dr. Robert Siblerud of Colorado State University in 1988, problems related to mental health were greater in patients with amalgams. Some of the common symptoms were irri-tability, anxiety and depression. One year after 86 of the test subjects had their amal-gams removed, 70% of the recorded symp-toms had either decreased or disap-peared.¹⁰⁵ Mercury intoxication also has been linked to mental symptoms such as moodiness, rage and anxiety.¹⁰⁶

A more recent study by Siblerud and colleagues provides further evidence that mercury amalgam fillings may be a causa-tive factor in depression, excessive anger and anxiety. The researchers compared scores on the Beck Depression inventory for 25 women who had mercury amalgam fillings and 23 who didn’t. Those with amalgams had sig-nificantly higher scores and reported more symptoms of fatigue and insomnia.¹⁰⁷

Reduced Immune Functioning

Not everyone who has dental amal-gams will develop highly visible reactions that demand medical attention. But even in cases where no easily identifiable disease occurs, mercury will diminish the effective-ness of the immune system.¹⁰⁸

Mercury is considered to be a strong immune depressant because it alters the number of T-cells. The cells decrease in number when amalgams are placed in the mouth and increase when the fillings are removed.109 The other metals contained in amalgam can affect the immune system as well. One recent study of 1,000 subjects found that 90% had immune reactions to mercury, 87% to copper, 83% to zinc, 56% to tin, and 45% to silver.¹¹⁰

In his study of mercury amalgam’s ef-fect on immunomodulatory reactions, Dr. Swartzendruber of the University of Colo-rado found that intra-oral heavy metals altered the quantity and quality of lymphocyte subset distributions. While functional analyses were not performed on the altered lymphocytes, he states, “The consistent finding of recurrent and inter-current infections strongly suggests that the symptomatic patients are immuno-compromised.” The reactive patients also experienced a serious loss of mononuclear cell viability.¹¹¹

More recently, these findings were con-firmed by animal experiments conducted in Sweden. In a 1994 study, 8-100 mg of silver amalgam or silver alloy was implanted in the peritoneal cavity of mice for 10 weeks or six months. The researchers found an unsettling litany of immune effects.¹¹²

Dental amalgam in genetically sensi-tive mice causes a chronic stimulation of the immune system with the induction of systemic autoimmunity. The authors con-clude that under appropriate conditions of genetic susceptibility and adequate body burden, heavy metal exposure from dental amalgam may contribute to human immu-nological aberrations, which could lead to overt autoimmunity. This research is strongly suggestive of a link between mer-cury amalgam and autoimmune disor-ders.¹¹³

Given these results, reports Dr. Swartzendruber, amalgam’s impact on im-munity should be carefully studied. “It is possible that such individuals may also be susceptible to other systemic effects of heavy metal, particularly since in the rat it is clear that heavy metals can induce autoimmune disorders. Heavy metals should be carefully considered as possible etiological agents in human diseases thought to have an autoimmune component.”¹¹⁴

A study of cytotoxicological effects on animal tissues concluded that the level of mercury and copper in amalgam filling materials makes them significantly more cytotoxic than either of two amalgam al-ternatives.¹²²

Effects on Dentists and Dental Personnel

The American Dental Association’s position on amalgam-related illness is ironic, given the effect amalgam has on those who work with it every day: dentists and their staff. As early as 1987 a Swedish study conducted for the Occupational Health Program of the Harvard School of Public Health assessed whether suicide rates were higher among dentists than other college-educated professionals over the 10-year course of the study. The study found that male dentists had an elevated standardized mortality ratio compared with other male academics. The authors concluded that the mental health conse-quences of mercury exposure among den-tists should be investigated further.¹²³

Related studies indicate that dentists may be more vulnerable to stress and conse-quent depression than members of other pro-fessions.¹²⁴ For example, a study of dentists in private practice in South Africa found that 10 percent had suicidal ideation.¹²⁵

A 1995 study documented the behavioral effects of low-level mercury exposure on dentists working with amalgam. Behavioral tests revealed significant defects, including poor mental concentration, emo-tional lability and mood problems in the mercury-exposed dentists compared with a control group of non-amalgam dentists.¹²⁶

A follow-up cross-study found that long-term exposure to amalgam can make dentists’ hands unsteady, which affects their manual dexterity. Researchers found re-markable differences in psychomotor per-formance between the amalgam and non-amalgam dentists. The most significant as-sociations were found for the Intentional Hand Steadiness Test. The authors warn that the IHST results should be carefully consid-ered by dental professionals who rely on manual dexterity in restorative dentistry.¹²⁷ That would include any dentist who does fillings, root canals or bridgework.

In a later study, the authors compared the degree of mercury in dentists’ tissues with measures of mercury toxicity, includ-ing fine manual speed, accuracy and coor-dination, that are of particular relevance for dental professionals who work with handheld tools. The study found subtle preclinical effects at very low levels of mer-cury exposure (less than 4 micrograms per liter of urine), with far more severe clinical deficits at higher mercury levels. Behavioral responses typically increased with exposure in a fairly uniform manner, indicating a more general response. These studies present new evidence that adverse behavioral effects may occur even with what is classified as low exposure.¹²⁸

Environmental Impact

Looking at the use of dental amalgam from an environmental point of view pro-vides another chilling perspective on this issue. Wastewater from dental offices is a significant source of environmental mer-cury pollution. A study of Danish dental clinics found that clinics with mercury separators released a mean value of 35 mg mercury per day. Clinics without separators released a mean value of 270 mg per day. Thus, several hundred grams of mercury per clinic may be discharged annually with the wastewater. The authors concluded that the use of efficient amalgam separators may reduce the mercury outlet markedly.¹²⁹

The ADA cites the widespread use of amalgam over the past 150 years as evi-dence of its safety. The organization sug-gests that “the most convincing support we have for the safety of dental amalgam is the fact that each year more than 100 million amalgam fillings are placed in the U.S.” This rationale offers little comfort to those who question amalgam’s use. “This is a chilling thought,” states the International Academy of Oral Medicine and Toxicology. “It should be a cause for concern that approximately 72 million tons of mercury are used annu-ally in dentistry, much of it being placed into the teeth of Americans.”¹⁴¹

The ADA also states that “studies have failed to find any link between amalgam restorations and any medical disorder. Amalgam continues to be a safe restora-tive material for dental patients.”¹⁴² In 1984 the ADA did alter its position slightly to admit that mercury escapes from amalgam. But it still maintained that the amounts in question were too small to cause any dam-age to the body.¹⁴³

The ADA no longer maintains that amalgam’s safety has been scientifically proven, according to the Academy. Nor does it offer certification of the safe and effective use of mixed amalgam. It says amalgam cannot be certified because it is mixed by individual dentists who must take responsibility for the material’s safety.^{144, 145}

The ADA filed legal briefs in which it abdicated any responsibility for the damage done by mercury amalgams in Tolhurst v. Johnson & Johnson, a California lawsuit in which a dental patient sued his dentist, two amalgam manufacturers, a distributor and the ADA itself. The brief stated: “The ADA owes no legal duty of care to protect the public from allegedly dangerous products used by dentists. The ADA did not manu-facture, design, supply, or install the mer-cury-containing amalgams. The ADA does not control those who do. The ADA’s only alleged involvement was to provide informa-tion regarding its use. Dissemination of in-formation relating to the practice of den-tistry does not create a duty of care to pro-tect the public from potential injury.”¹⁴⁶

The court agreed that the ADA bore no responsibility for the use of amalgam and dismissed it from the case.¹⁴⁷ Apparently we are expected to ignore the fact that the ADA holds the patents on the high-copper amal-gam currently in use by most dentists, is responsible for certifying all dental schools in the United States, and certainly does not encourage cutting-edge dentists who use any product or procedure other than what they were taught in dental school.

Meanwhile, how has the U.S. govern-ment responded to the debate over dental amalgam? While the EPA has defined mer-cury amalgam as a hazardous substance, the FDA has skirted the issue of amalgam safety over the years. When 1976 legisla-tion required the FDA to classify all medi-cal and dental devices, the agency “grandfathered” its approval of the long-used amalgam fillings under the GRAS (generally recognized as safe) category, ac-cording to Joyal W. Taylor, D.D.S., who founded the Environmental Dental Asso-ciation to spearhead a movement for in-formed consent legislation concerning amalgam’s use.¹⁴⁸

One decade later, in 1987, the FDA’s Classification of Dental Devices was pub-lished in the Federal Registry. Dental amal-gam, it turned out, was not even listed as a dental device, based on the rationale that amalgam is a reaction product. Instead, the FDA classified the components of amalgam, which means that amalgam itself has never been approved as a dental device, according to the Environmental Dental Association. Therefore, it has not undergone the “rigor-ous biocompatibility testing required of all other medical implant devices.”¹⁴⁹

Then Oakland’s Environmental Law Foundation and a Washington, D.C., organi-zation called Consumers for Dental Choice brought suit against the state’s dental amal-gam manufacturers and distributors, de-manding they meet their obligations under Proposition 65 by placing warning labels on their products and in the offices of dentists who use them. Such labels are already in use in many countries, including all those of the European Union.¹⁵⁵

After three years of legal process, on November 15, 2000 a judge of the Superior Court of California in San Francisco issued a consent decree requiring California amal-gam manufacturers to disclose to their customers the potential for birth defects and reactions to other toxic dental materi-als.¹⁵⁶ This was a small but significant step in the effort to inform consumers about the dangers of mercury amalgam.

Another step toward disclosure was taken in June 2001, when Charles Brown and Shawn Khorrami, a public interest at-torney, filed a lawsuit against the ADA and its California affiliate charging them with deceiving people into thinking dental amal-gams are made of silver when a major component of the fillings is in fact mercury. The lawsuit was filed on behalf of organiza-tions and individuals that want to eliminate mercury’s use in amalgam fillings. The groups include Kids Against Pollution, the American Academy of Biological Dentistry, and Dental Amalgam Mercury Syndrome Inc.¹⁵⁷

The attorneys also served the legally required notice that they would sue the ADA under the provisions of California’s Proposition 65. Khorrami stated: “…Our complaint is not with individual dentists, many of whom share our concern about the use of mercury, but with the ADA, which has a vested economic interest in the con-tinued use of mercury and which has exer-cised undue and unfair pressure on den-tists not to warn their patients of the dan-gers of mercury.”¹⁵⁸

The state of Colorado also has in-creased consumer choice in this area. In 1997 Governor Roy Romer signed into law a bill to enhance access to mercury-free dentistry for the people of that state. House Bill 97-1187 was introduced by Rep. Mark Paschall with the support of Sen. Muntzebaugh to support consumers’ rights to choose safe, effective alternatives to con-ventional dental procedures.¹⁵⁹

This dental freedom law is the first of its kind to be passed in the United States. It enables patients to choose mercury-free dentistry through dentists licensed in Colo-rado. It further assures that trained and licensed dentists can continue to practice mercury-free dentistry without fear of ret-ribution from the Colorado Board of Den-tal Examiners.¹⁶⁰

The Trickle-down Effect

The ADA’s position on mercury carries considerable weight. Since state dental boards tend to operate in general agree-ment with the ADA, its philosophy trickles down to the local level. Dentists who place alternative fillings tend to be looked at more carefully, although this varies from state to state. Dentists who malign mercury as hazardous are threatened with expulsion from the ADA in four states.¹⁶¹ And the dental leadership in several states threat-ens to censure dentists who inform patients that amalgam contains mercury.¹⁶²

According to the ADA’s Code of Eth-ics, any dentist who removes a serviceable amalgam filling from a nonallergic patient for the purpose of removing toxic sub-stances (such as mercury) from the body is acting unethically. The ADA’s edict speci-fies that the treatment is improper when it is “performed solely at the recommenda-tion or suggestion of the dentist.”¹⁶³

Another country that has considered the amalgam issue is Australia. The government’s primary medical watchdog, the National Health and Medical Research Council (NHMRC), has found mercury amalgam to be safe and effective even though it was pre-sented with data on the dangers of amalgam from the Australasian Society of Oral Medi-cine and Toxicology. ASOMAT submitted a report to the NHMRC in 1998 that docu-mented research on mercury and recom-mended that the use of amalgam be phased out over three to five years.

The report, authored by Dr. Roman Lohyn and Dr. Robert Gammal, also recom-mended that amalgams not be used in the following people or circumstances: pregnant women, breastfeeding women, children un-der the age of 6, people with kidney problems, people with neurological problems, in retro-grade root-canal fillings, as cores underneath metal-based crowns, in conjunction with other metals in the mouth, in people with diagnosed lichen planus, and in people with a compromised immune system.¹⁷⁴

A Working Party formed by the NHMRC to study the issue found mercury amalgam to be safe and effective. However, the group also advised that it would be prudent to use alternatives to amalgam for children, preg-nant women and people with kidney disease. A risk assessment was then completed in 2001, and this assessment also found that amalgam was safe and effective.^{175, 176}

A Challenge To The ADA

The International Academy of Oral Medicine and Toxicology issued this re-sponse in mid-1990 to the ADA’s then-recent statement of confidence in amalgam: “Given the inconsistencies between the scientific facts and the American Dental Association Special Report, the (Academy) has serious concerns regarding the ADA’s lack of scien-tific rigor and the tendency to misinform the dental profession and, thereby, the public at large regarding the established scientific facts about amalgam safety.”

“We hereby call to task the ADA for failure to adequately support their position on dental amalgam with hard scientific data. This failure has resulted in inadequate protection to the public and inadequately protects the membership of the ADA from personal harm due to amalgam usage.”¹⁷⁷

Likewise, researchers at the University of Calgary reached this conclusion follow-ing their 1989 study of amalgam: “Our find-ings are at variance with the anecdotal opin-ion of the dental profession, which claims that amalgam fillings are safe. Experimen-tal evidence in support of amalgam safety is at best tenuous. From our results, we con-clude that dental amalgam can be a major source of chronic mercury exposure.”¹⁷⁸

Today the burden of proof regarding the safety of amalgam lies with those who defend its use, according to Victor Penzer,

M.D. Its advocates must offer convincing support of their position, given the many studies that show a substantial danger in using mercury amalgams. “Only valid sci-entific evidence of safety could possibly justify the continuation of amalgam use in dental practice,” he states.¹⁷⁹ In fact, toxic-ity experts such as Thomas Clarkson of the University of Rochester Medical School and Lars Friberg of the Karolinska Institute argue against the notion of a “safe” level of mercury exposure.¹⁸⁰

In the future, frontier societies such as the United States must rise above their history of exploiting natural resources with-out regard for the long-term consequences. Much like the strip mine, the use of harmful pesticides and deforestation, mercury amal-gam is a legacy to a pay-later society. But the days of indiscriminate use of resources are long gone, and we must now establish a new ethic in tune with our new reality.

Society of Oral Medicine and Toxicology sub-mission to amalgam review working party of Australia’s National Health and Medical Re-search Council, Part B. May 1988; 50.

1. Kidd RF: Results of dental amalgam removal and mercury detoxification using DMPS and neural therapy. Altern Ther Health Med, 2000 Jul; 6(4): 49-55.

1. Lohyn R, Gammal R: Highlights of ASOMAT’s 2 part submission. Amalgam Review Working Party of Australia’s National Health and Medi-cal Research Council, Part A. June 15-16, 1998;

2. 6.
2. Lohyn, Part A, 6-8.

3. Weiner JA, Nylander M: An estimation of the uptake of mercury from amalgam fillings based on urinary excretion of mercury in Swedish subjects. Sci Total Environ, 1995 Jun 30; 168(3): 255-65.

1. Hahn LJ, Kloiber R, Vimy MJ, et al: Dental “sil-ver” tooth fillings: a source of mercury expo-sure revealed by whole-body image scan and tissue analysis. FASEB J, 1989 Dec; 3(14): 2641-

2. 6.
4. Ziff S, Ziff MF, DDS: Dentistry Without Mer-cury. Orlando, FL. Bio-Probe Inc.; 11.

5. Weiner and Nylander.

6. Ibid.

7. From an interview conducted by Gary Null as part of an investigative journalism series on mercury amalgam for his "Natural Living" ra-dio program. Quoted material comes from the transcription of the program.

8. Ziff and Ziff.

9. Friberg L, Kullman L, Lind B, et al: Mercury in the central nervous system in relation to den-tal amalgam. Lakartidningen, 1986 Feb 12; 83(7): 519-22.

10. World Health Organization: Environmental Health Criteria Series, 1991.

11. Lorscheider FL, Vimy MJ, Summers AO. Mer-cury exposure from “silver” tooth fillings: emerging evidence questions a traditional den-tal paradigm. FASEB J, 1995 Apr; 9(7): 504-8.

12. Begerow J, Zander D, Freier I, er al: Long-term mercury excretion in urine after removal of amalgam fillings. Int Arch Occup Environ Health, 1994; 66(3): 209-12.

13. Aposhian HV, Bruce DC, Alter W, et al: Urinary mercury after administration of 2,3-dimercaptopropane-1-sulfonic acid:correlation with dental amalgam score. FASEB J, 1992 Apr; 6(7): 2472-6.

14. Huggins, Medical and Legal, 1-2, 19.

15. Patterson JE, et al: Mercury in human breath from dental amalgam. Bull Environ Contam Toxicol, 1985 Apr; 34(4): 459-68.

1. Stortebecker.

2. Huggins, Medical and Legal Implications, 3.

3. Stortebecker.

4. Siblerud RL, Motl J, Kienholz E: Psychometric evidence that mercury from silver dental fill-ings may be an etiological factor in depression, anger, and anxiety. Psychol Rep, 1994 Feb; 74(1): 67-80.

5. Stortebecker.

6. Silver, Natural Living Newsletter, No. 32.

7. Vimy MJ, Lorscheider FL: Serial measurements of intra-oral air mercury: estimation of daily dose from dental amalgam. J Dent Res, 1985 Aug; 64(8): 1072-5.

8. Svare CW, Peterson LC, Reinhardt JW, et al: The effect of dental amalgams on mercury lev-els in expired air. J Dent Res, 1981; 60: 1668-71.

9. Gebel T, Dunkelberg H: Influence of chewing gum consumption and dental contact of amal-gam fillings to different metal restorations on urine mercury content. Zentralbl Hyg Umweltmed, 1996 Nov; 199(1): 69-75.

10. Motorkina AV, Barer GM, Volozhin AI: Patterns of mercury release from amalgam fillings into the oral cavity. Stomatologiia (Mosk), 1997; 76(4): 9-11.

11. Ziff and Ziff, Dentistry Without Mercury, p. 17, citing Stortebecker P: Mercury poisoning from dental amalgam — a hazard to human brain. 1985; 32-43.

12. Lorscheider FL, Vimy MJ, Summers AO: Mer-cury exposure from “silver” tooth fillings: emerging evidence questions a traditional den-tal paradigm.

13. Stortebecker.

14. Svare.

15. From an interview conducted by Gary Null as part of an investigative journalism series on mercury amalgam for his "Natural Living" ra-dio program. Quoted material comes from the transcription of the program.

16. Ibid56 Eggleston and Nylander.

1. Nylander M, Friberg L, Lind B: Mercury con-centrations in the human brain and kidneys in relation to exposure from dental amalgam fill-ings. Swed Dent J, 1987; 11(5): 179-87.

2. Maas C, Bruck W, Haffner HT, et al: Study on the significance of mercury accumulation in the brain from dental amalgam fillings through direct mouth-nose-brain transport (article in German). Zentralbl Hyg Umweltmed, 1996 Feb; 198(3): 275-91.

3. Report of ICBM conference, 3.

4. Galic N, Prpic-Mehicic G, Prester L, et al: Den-tal amalgam mercury exposure in rats. Biometals, 1999 Sept; 12(3): 227-31.

New York. Quicksilver Press. 1998; 69-70.

from silver dental fillings may be an etiological factor in multiple sclerosis. Sci Total Environ, 1994 March 15; 142(3): 191-205.

als and trace elements in plasma and cerebro-spinal fluid in normal aging and Alzheimer’s disease. J Neural Transm Park Dis Dement Sect, 1991; 3(4): 231-58.

1. Ziff and Ziff, 33.

2. Saxe SR, Snowdon DA, Wekstein MW, et al: Dental amalgam and cognitive function in older women: findings from the Nun Study. J Am Dent Assoc, 1995 Nov; 126(11): 1495-501.

3. Ziff and Ziff, 34.

4. Ibid.

1. Olivieri G, Brack C, Muller-Spahn F, et al: Mer-cury induces cell cytotoxicity and oxidative stress and increases beta-amyloid secretion and tau phosphorylation in SHSY5Y neurob-lastoma cells. J Neurochem, 2000 Jan; 74(1): 231-

2. 6.
5. Leong CC, Syed NI, Lorscheider FL: Retro-grade degeneration of neurite membrane struc-tural integrity of nerve growth cones following in vitro exposure to mercury. Neuroreport, 2001 Mar 26; 12(4): 733-7.

6. Ibid.

7. Siblerud R:. Report of International Confer-ence on the Biocompatibility of Materials. Colo-rado State University, 1988, 21.

8. Stortebecker, 19-21.

9. Siblerud RL, et al: Psychometric evidence that mercury from silver dental fillings may be an etiological factor in depression, anger, and anxi-ety.

10. Huggins Diagnostic Center, The Proper Amal-gam Removal Booklet, 17.

11. Silver, Natural Living Newsletter, No. 32.

12. Huggins, Mercury, 12.

13. Swartzendruber DE, PhD: Adverse immunomodulatory effects of heavy metals in dental materials. Int J of Biosocial Med Re-search, 1990; 12(2): 134.

14. Hultman P, Johansson U, Turley SJ, et al: Ad-verse immunological effects and immunity in-duced by dental amalgam and alloy in mice. FASEB J, 1994; 8: 1183-90.

15. Pendergrass.

16. Swartzendruber.

17. Vimy MJ, Hooper DE, King WW, et al: Mer-cury from maternal “silver” tooth fillings in sheep and human breast milk. A source of neonatal exposure. Department of Medicine, Faculty of Medicine, University of Calgary, Al-berta, Canada. Biol Trace Elem Res, 1997 Feb; 56(2): 143-52.

18. Quicksilver Associates, 69-70.

19. Summers AO, Wireman J, Vimy MJ, et al: Mer-cury released from dental “silver” fillings pro-vokes an increase in mercury- and antibiotic-resistant bacteria in oral and intestinal floras

of primates. Antimicrob Agents Chemother, 1993 Apr; 37(4): 825-34.

1. Quicksilver Associates, 71.

2. Hahn, 2644-2645.

3. Huggins Diagnostic Center, The Proper Amal-gam Removal Booklet, 7.

4. Shaini FJ, Shelton RM, Marquis PM, et al: In vitro evaluation of the effect of freshly mixed amalgam and gallium-based alloy on the viabil-ity of primary periosteal and osteoblast cell cultures. Biomaterials, 2000 Jan; 21(2): 113-9.

5. Ibid.

6. Osborne JW, Albino JE: Psychological and medical effects of mercury intake from dental amalgam. A status report for the American J ournal of Dentistry. Am J Dent, 1999 Jun; 12(3): 151-6.

7. Shurtz JD, Mayhew RB, Cayton TG: Depres-sion. Recognition and control. Dent Clin North Am, 1986 Oct; 30(4 Suppl): S55-65.

8. Moller AT, Spangenberg JJ: Stress and coping amongst South African dentists in private prac-tice. J Dent Assoc S Afr, 1996 Jun; 51(6): 347-57.

9. Echeverria D, Heyer NJ, Martin MD, et al: Behavioral effects of low-level exposure to Hg0 among dentists. Neurotoxicol Teratol, 1995 Mar-Apr; 17(2): 161-8.

10. Bittner AC, Echeverria D, Woods JS, et al: Behavioral effects of low-level exposure to Hg0 among dental professionals: a cross-study evaluation of psychomotor effects. Neurotoxicol Teratol, 1998 Jul-Aug; 20(4): 429-39.

128.Echeverria D, Aposhian HV, Woods JS, et al: Neurobehavioral effects from exposure to den-tal amalgam Hg(o): new distinctions between recent exposure and Hg body burden. FASEB J, 1998 Aug; 12(11): 971-80.

129. Arenholt-Bindslev D, Larsen AH: Mercury lev-els and discharge in waste water from dental clinics. Water Air and Soil Pollution, 1996 Jan; 86(1-4): 93-9.

130. Mercury Free and Healthy, The Dental Amal-gam Issue. DAMS Inc. along with Consumers for Dental Choice, A Project of the National Institute for Science, Law and Public Policy, Washington, DC. Mercury Free and Healthy, The Dental Amalgam Issue. DAMS Inc. along with Consumers for Dental Choice.

131. Skare I, Engqvist A: National Institute of Oc-cupational Health, Human exposure to mer-cury and silver released from dental amalgam restorations. Arch Environ Health, 1994 Sep-Oct; 49(5): 384-9.

13.2 Association of Metropolitan Sewerage Agen-cies’ Evaluation of Domestic Sources of Mer-cury. http://www.amsa-cleanwater.org/pubs/ mercury/mercury.htm.

www.lauralee.com/warren.htm.