23 May 2001
The Honorable Dan Burton
Committee on Government Reform
U.S. House of Representatives
RE: May 11th letter by Robert M. Anderton,
D.D.S., J.D., LL.M. and President of the ADA, challenging my
statement to the Committee on Government Reform looking at the
topic, Autism-Why the Increased Rates? A One Year Update.
Dear Mr. Chairman:
At the April 25th meeting of your committee
I gave testimony that the President of the American Dental Association
(ADA) takes exception to in a letter sent to you dated 11 May
2001. Quoting from that letter the testimony the ADA dislikes
is "that elementary mercury from dental amalgam could
work synergistically with other ethyl-mercury sources and
have a cumulative toxic effect on the body. Dr. Haley postulated
that this could be a potential cause of autism and Alzheimer's
disease." I stand by my statement as a sensible concern
based on published scientific research regarding synergist toxicities
caused by two very toxic agents, mercury and the organic mercury
compound thimerosal. This concern is elevated since mercury exposure
from amalgams to a pregnant mother concentrates in the fetus
and a single vaccine given to a six-pound newborn is the equivalent
of giving a 180-pound adult 30 vaccinations on the same day.
Include in this the toxic effects of high levels of aluminum
and formaldehyde contained in some vaccines, and the synergist
toxicity could be increased to unknown levels. Further, it is
very well known that infants do not produce significant levels
of bile or have adult renal capacity for several months after
birth. Bilary transport is the major biochemical route by which
mercury is removed from the body, and infants cannot do this
very well. They also do not possess the renal (kidney) capacity
to remove aluminum. Additionally, mercury is a well-known inhibitor
of kidney function. Common sense indicates that the concern I
expressed should be taken seriously since we do not know how
combined toxicities effect humans, especially in utero.
Consider the current epidemic death on birth of over 500 foals
from apparently healthy mares around Lexington, KY. These deaths
were identified as being due to a low level toxicity delivered
by caterpillars eating poison plants and later, on migration,
depositing their waste products on grass being eaten by the mares.
The point being it is the infant in utero that suffered
most on exposure to low level, toxins, not the mother. Combined
mercury toxicities can be devastating as I reference below and
in the many references available on the www.altcorp.com
website. What is needed is research by non-biased scientists
to clarify this, something our FDA and NIDCR have refused to
do. As the American public find out what has happened regarding
this issue, they will be quite angry. This is a biomedical science
issue that should have been resolved a long time ago by the responsible
Below I present detailed and referenced information
supporting my case and respond to various statements made by
the ADA President that I believe to be misleading and sometimes
flagrantly wrong. The ADA seems to think it has the right to
select which research it believes and to trash that research
that says it is wrong, even though the latter represents the
bulk of published research. To address the issues raised by the
ADA President in his letter I will go in sequential order of
the comments made in the letter placing the ADA comments in italics
and providing scientific references for my conclusions.
"There is no scientifically valid
evidence linking either autism or Alzheimer's disease with dental amalgam". First, mercury
is a well-known, potent neurotoxicant, and common sense would
lead to the conclusion that severe neurotoxins would exacerbate
all neurological disorders, including Parkinson's, ALS, MS, autism
and AD. Several research papers in refereed, high quality journals
and scientific publications have shown that mercury inhibits
the same enzymes in normal brain tissues as are inhibited in
AD brain samples (1a-c, 2, 3). AD is pathologically confirmed
post-mortem by the appearance of neuro-fibillary tangles (NFTs)
and amyloid plaques in brain tissue. Published research, within
the past year, has shown that exposure of neurons in culture
to sub-lethal doses of mercury (much less than is observed in
human brain tissue) causes the formation of NFTs (4), the increased
secretion of amyloid protein and the hyper-phosphorylation of
a protein called Tau (5). All three of these mercury-induced
aberrances are regularly identified as the major diagnostic markers
for AD. In the manuscript published in the J. of Neurochemistry
(5) the authors state "These results indicate that mercury
may play a role in the patho-physiological mechanisms of AD."
In most of these experiments, mercury and only mercury among
the several toxic heavy metals tested, caused the AD related
responses reported. Many medically trained individuals would
agree that if something causes the appearance of the pathological
hallmarks confirming the disease then it likely causes the disease.
I at least have limited my claims to exacerbation of these diseases
to err on the side of caution.
Further, consider this about AD. A study of
500 sets of identical twins from World War II era lead to the
conclusion that sporadic AD which represents 90% of the cases
was not a directly inherited disease. In many cases one twin
would get AD and the other would not. Genetic susceptibility
is involved, but a toxic exposure is required (e.g., if you are
genetically susceptible to being an alcoholic you still need
to be exposed to alcohol to become one). The work by Rose's group
at Johns Hopkins University implicates APO-E genotype as a "risk"
factor with APO-E2 being protective and APO-E4 being a major
risk factor. APO-E2 has the ability to protect the brain from
mercury by having two additional thiol-groups to bind mercury
appearing in the cerebrospinal fluid whereas APO-E4 does not
have this additional capability (1). This may explain the proven
genetic susceptibility to AD of the APO-E4 carriers.
NIH has spent hundreds of millions of dollars
to find a causal factor for AD. Yet, no virus, yeast or bacteria
has been identified so the cause remains unknown to general science.
The rate of AD per 1,000 population is nearly the same in California,
Michigan, Maine, North Carolina, Florida, Texas, etc. It is not
significantly different for rural versus urban individuals, or
factory workers versus those with outside jobs. So the primary
toxicant that may be involved is most likely not environmental.
Therefore, it must be a very personal toxicant, like what you
put in your mouth. Since we place grams of a neurotoxic metal,
mercury, in our mouths in the form of dental amalgam this makes
it a good suspect for the exacerbation of AD---not that all would
be affected, just those that are genetically susceptible, or
those who become ill enough to fall prey to the toxicity, or
those that are also exposed to another synergistic toxin (see
The one fact that ties mercury into a major
suspect for AD is the fact that most of the proteins/enzymes
that are inhibited in AD brain are thiol-sensitive enzymes. Mercury
is one of the most potent chemical inhibitors of thiol-sensitive
enzymes and mercury vapor easily penetrates into the central
nervous system (2). Mercury is not the only toxicant to inhibit
thiol-sensitive enzymes. Thimerosal and lead will do this also
as well as reactive oxygen compounds created in oxidative stress
and many other industrial compounds. However, mercury has been
reported to be significantly elevated in AD brain (14a,b, 15).
Mercury is in many mouths being emitted from dental amalgam and
absolutely would exacerbate the clinical condition identified
as AD. Therefore, mercury should be considered as a causal contributor
since mercury can produce the two pathological hallmarks of the
disease and inhibits the same thiol-sensitive enzymes that are
dramatically inhibited in AD brain.
It is documented by a 1991 World Health Organization
report that dental amalgams constitute the major human exposure
to mercury. Grams of mercury are in the mouths of individuals
with several amalgam fillings. Further, the level of blood and
urine mercury positively correlates with the number of amalgam
fillings. This was confirmed by a recently published NIH funded
study (6). Therefore, I fail to see the ADA's viewpoint that
there is no scientifically valid evidence linking mercury from
amalgams to exacerbating AD, especially since mercury produces
the diagnostic hallmarks of AD (4,5). The ADA hides behind the
fact that there has not been an epidemiological study to attempt
to correlate mercury exposure and AD. However, absence of proof
is not proof of absence. This also begs the question why the
ADA, the FDA and the National Institutes of Dental Craniofacial
Research (NIDCR) have not pushed for such a study? These agencies
know this would be immensely expensive and only the U.S. government
could afford to support any reliable long-term study. Yet, these
same responsible agencies have failed to confirm as safe the
placing into the mouth of Americans grams of the most toxic heavy
metal Americans are exposed to. The dental branch of the FDA
has steadfastly refused to investigate the toxic potential of
Look at the references in the ADA letter!
Even they must quote Scandinavian literature to support their
contentions of safety, and even then they have to reference papers
on fertility instead of neurotoxicity! Where is the ADA, FDA
and NIDCR supported U.S. research in this area? Go to the NIH
web-sites and look for research on the safety of mercury from
amalgams, or try to find an NIH study concerning possible mercury
involvement in any common neurological diseases. NIH does support
research on methyl-mercury, as we seem to like beating up on
the fishing industry whilst leaving the dental industry alone.
However, according to the NIH study about 90% of the mercury
in our bodies is elemental mercury, not methyl-mercury, showing
the exposure is more likely from dental amalgams rather than
fish (6). Support at NIH has been very sparse for investigating
the relationship of elemental mercury exposure to neurological
"And there is no scientifically valid
evidence demonstrating in vivo
transformation of inorganic mercury into organo mercury species
in individuals occupationally exposed to amalgam mercury vapor".
There was a paper published entitled "Methylation of Mercury
from Dental Amalgam and Mercuric Chloride by Oral Streptococci
in vitro" (19). This strongly indicates that "organo
mercury species" are indeed capable of being made in the
human body and may explain the appearance of methyl-mercury in
the blood and urine of individuals who don't eat seafood.
Further, periodontal disease is considered
one of the major risk factors for stroke, heart and cardiovascular
disease and late onset, insulin independent diabetes. Many studies
of the toxicants produced in periodontal disease have identified
hydrogen sulfide (H2S) and methane-thiol (CH3SH) as major toxic
products of infective anerobic bacteria in the mouth metabolizing
the amino acids cysteine and methionine, respectively. These
volatile thiol-compounds are what cause bad-breath! Methane-thiol
(CH3SH) would react immediately and spontaneously in the mouth
with amalgam generated mercury cation to produce the following
two compounds, CH3S-HgCl and CH3S-Hg-SCH3, which are organo-mercurial
compounds (check this out with any competent chemist). They are
also very similar in structure to methyl-mercury (CH3-HgCl) and
dimethyl-mercury (CH3-Hg-CH3), the latter which caused the highly
publicized death of a University of Dartmouth chemistry professor
10 months after she spilled two drops on her gloved hand. We
have synthesized CH3S-HgCl and CH3-Hg-CH3 in my laboratory and
tested their toxicity in comparison to Hg2+. As expected, they
were both more toxic than Hg2+ and this data is available on
the www.altcorp.com web-site.
Therefore, the ADA President is badly misinformed on this issue.
Additionally, I am amazed that the researchers at the ADA and
NIDCR did not previously report on this obvious chemistry as
I would imagine this is the kind of topic they should be addressing.
"Based on currently available scientific
evidence, the ADA believes that dental amalgam
is a safe, affordable and durable material for all but a handful
of individuals who are allergic to one of its components.
It contains a mixture of metals such as silver, copper and
tin, in addition to mercury, which chemically binds these components
into a hard, stable and safe substance." This is
a totally wrong statement unless you underline the "ADA
believes" and define how big is a "handful of
individuals". Sensible people want "believes"
replaced with "knows" and a "handful" replaced
with a "hard number". Amalgams emit dangerous levels
of mercury and the ADA absolutely refuses to accept this fact
or even to study the possibility. Otherwise, the ADA administrators
seem to be unable to separate fact from fiction. Consider, if
they wanted to destroy my argument on amalgam toxicity they would
reference several solid, refereed publication showing that mercury
is not emitted from dental amalgams---but they cannot do this
with even one article. They always state the "estimate"
is that a very, very, very small amount. Competent, well-informed
researchers don't use the evasive language used in the ADA President's
letter. They would state the amount is so many micrograms mercury
released per centimeter squared amalgam surface area and a "handful
of individuals" would be a percentage of our population!
Lets look at the published literature.
First, careful evaluation of the amount of
mercury emitted from a commonly used dental amalgam in a test
tube with 10 ml of water was presented in an article entitled
"Long-term Dissolution of Mercury from a Non-Mercury-Releasing
Amalgam". This study showed that "the over-all mean
release of mercury was 43.5 ± 3.2 micrograms per cm2/day,
and the amount remained fairly constant during the duration of
the experiments (2 years)" (7). This was without pressure,
heat or galvanism as would have occurred if the amalgams were
in a human mouth. Further, research where amalgams containing
radioactive mercury were placed in sheep and monkeys, showed
the radioactivity collecting in all body tissues and especially
high in the jaw and facial bones. (8,9). Another publication,
from a major U.S. School of Dentistry, stated that solutions
in which amalgams had been soaked were "severely cytotoxic
initially when Zn release was highest" (13). Zn is a needed
element for body health and is found in very low percentages
in dental amalgams when compared to mercury and why mercury was
not mentioned in the abstract of this publication baffles me.
Why would the statement be true? Because Zn2+ is a synergist
that enhances mercury toxicity! However, does this sound like
amalgams are a safe, stable material? We have repeated similar
amalgam soaking experiments in my laboratory and the results
can be seen at www.altcorp.com. Cadmium (from smoking), lead,
zinc and other heavy metals enhanced mercury toxicity as expected
(this research is currently being prepared for publication).
The ADA claim that a zinc oxide layer is formed
on the amalgams that decreases mercury release is true, if you
don't use the teeth. The zinc oxide layer would be easily removed
by slight abrasion such as chewing food or brushing the teeth.
Further, my laboratory has confirmed that solutions in which
amalgams have been soaked can cause the inhibition of brain proteins
that are inhibited by adding mercury chloride, and these are
the same enzymes inhibited in AD brain samples.
Further, mercury emitting from a dental amalgam
can be easily detected using the same mercury vapor analysis
instrument used by OSHA and the EPA to monitor mercury levels.
Anyone who does not believe mercury is emitted from amalgams
should consider doing the following. Have your local dentist
make 10 amalgams using the same material he/she places in your
mouth. Take these 10 amalgams to your nearest research university's
department of chemistry or toxicology department and have them
determine how much mercury is being emitted. For example, have
them calculate how long it would take a single spill of hardened
amalgam to make a gallon of water too toxic to pass EPA standards
as drinking water. You will then have an answer from an unbiased,
solid group of scientists who are trained to do such determinations.
Also, remember the level of mercury they measure would not include
the increase that would occur with amalgams in the mouth where
chewing, grinding your teeth, drinking hot liquids and galvanism
greatly increase the release of mercury. Since this approach
can be easily done by anyone don't you think the ADA, FDA and
other amalgam supporters would have this published by now if
the level of mercury released was below the danger level?
Here is their attempt. According to an ADA
spokesman he has "estimated" that only 0.08 micrograms
of mercury per amalgam per day is taken into the human body.
Applying simple math to this "estimate" of 0.08 micrograms/
day one would divide this amount by 8,640 (24 hours/day X 60
minutes/hour X 6 ten second intervals/minute) to determine the
amount of mercury in micrograms available for a ten second mercury
vapor analysis. Consider that somewhere between one-half to five-sixths
of the mercury released would be into the tooth (that area of
the amalgam that exists below the visibly exposed amalgam surface)
and not into the oral air. In addition, some mercury in the oral
air would be rapidly absorbed into the saliva and oral mucosa
(mercury loves hydrophobic cell membranes) and also not be measured
by the mercury analyzer. Further, as the mercury analyzer pulls
mercury containing oral air into the analysis chamber, mercury
free ambient air rushes into the oral cavity decreasing the mercury
concentration. Taking all of this into account you can calculate
that most mercury analyzers could not detect this "estimated"
0.08 micrograms/day level of mercury even if you had several
amalgams. However, the fact is that it is quite easy to detect
mercury emitting from one amalgam using these analyzers. Therefore,
the "estimate" by this ADA spokesman is way to low.
Also, if you gently rub the amalgam with a tooth-brush the amount
of mercury emitted goes up dramatically. This is a test anyone
can do and demonstrate to any group. The ADA spokesmen state
that the mercury vapor analyzer is not accurate at determining
oral mercury levels and they are quite correct. However, using
this instrument would greatly underestimate the amount of mercury
exiting the amalgam. The very fact that the mercury analyzer
detects high levels of oral mercury strongly indicates the emitted
amount of mercury is too high to be acceptable.
Mercury release from dental amalgams is also
the reason OSHA has used this analyzer to make the dentists place
unused amalgam in a sealed container under liquid glycerin. This
is done so that the mercury vapors from the amalgams will not
contaminate the dental office making it an unsafe place to work.
This is also the reason the EPA insists that removed amalgam
filling and extracted teeth containing amalgam material be picked
up and disposed of as toxic waste. Apparently, the only safe
place for amalgams is in the human mouth if you believe what
the ADA believes.
"Amalgams have been used for 150 years
and, during that time, has established an
extensively reviewed record of safety and effectiveness."
First, what other aspect of industry or medicine is still using
the same basic manufactured material that they used 150 years
ago? One has to ask the question as to what has hindered the
progress of development of better and safer dental materials?
Also, consider that in the early 1900s the average life expectancy
of most Americans was about 50 years of age and most of them
could not afford dental fillings. Fifty to sixty years is much
less than the average age of onset of AD. Further, amalgams became
more available to most working class Americans after World War
II, or in the early 1950s. The greatest increase in the use of
amalgam occurred at about this time and these 'baby boomers are
the great ongoing amalgam experiment'. They are now reaching
the age where AD appears and have lived most of their lives carrying
amalgam fillings. They also wonder what is causing their chronic
fatigue as the physicians can find nothing systemically wrong
with them. I would encourage all concerned to contact the health
experts on the rate of increase of AD in the U.S.A. at this time.
Consider the cost it will place on the taxpayer and how much
we would save if we could even remove the exacerbation factors
that might speed up the onset of AD. I must point out that the
"extensively reviewed record of safety" mentioned
in the ADA letter was mostly done by dentists and committees
dominated by ADA dentists. Also, much of the "safety opinion"
was developed long before words like Alzheimer's disease and
chronic fatigue were commonplace. Further, these were "reviews"
and not carefully documented studies based on scientific experimentation
and done by unqualified dentists, not medical scientists. Dentists
are not trained to do basic research, nor are they trained in
toxicology. Furthermore, the ADA does have a vested interest
in keeping amalgam use legitimate. The ADA was founded on using
amalgam technology and participated in patenting and licensing
amalgam technology. One has to question why there has not been
a general outcry by the bulk of well-meaning dentists and their
patients and this question should be addressed. The International
Association of Oral Medicine and Toxicology, started by American
& Canadian dentists, does adamantly disagree with the ADA
on the issue of safety of dental amalgams and this organization
has the mantra of "Show me your science" with regards
to all dental issues.
The ADA, through state dental boards stacked
with ADA members, has instigated a "gag order" preventing
dentists from even mentioning to their patients that amalgams
are 50% mercury. Dentists cannot state that mercury is neurotoxic
and emits from amalgams and that the dental patient should consider
this as they select the tooth filling material they want used.
If a dentist informs a patient of these very truthful facts he
will be consider not to be practicing good dentistry and his
license will be in jeopardy. Attacking a person's freedom of
speech because he is telling the truth and causing serious questions
to be asked about the protocols pushed by a bureaucracy (the
ADA) makes me seriously question the commitment the ADA has for
the health of the American people. The negative stand taken by
many state dental boards against even informing the patients
about the mercury content of amalgams and the other filling choices
they have does not speak well for the organized dental profession.
What medical group would give a treatment to a patient without
telling them of the risks involved?
"Issued late in 1997, the FDI World
Dental Federation and the World Health Organization
consensus statement on dental amalgam stated "No controlled
studies have been published demonstrating systemic adverse
effects from amalgam restorations."" My first comment
would be to question "who staffed these committees and what
percentage were connected to the ADA though the NIDCR or the
FDA dental materials branch or other relationships?" We
appear to have the foxes guarding the henhouse! Then I would
again point out that "absence of proof is not proof of absence".
I would then ask 'have any controlled studies been done and if
not, why not?' If the ADA dentists insist on placing amalgams
in the mouth, are they not required to show it is safe, not the
other way around? Should not the ADA and others concerned push
to require the FDA to prove amalgams are safe instead of totally
ducking this issue. Go to the FDA dental materials web-site and
try to find any evaluation of amalgam safety---you will not succeed.
The dental branch of the FDA refuses to do a safety study on
amalgams and this is shame on our government.
"the small amount of mercury released
from amalgam restorations, especially during
placement and removal, has not been shown to cause anyadverse
effects." This increase in mercury exposure has also not
been shown to be safe by proving it does not cause any adverse
effects! Are we to believe this elevated exposure to a toxic
metal is good for us? If one were in a building that caused the
rise in blood/urine mercury that appears after dental amalgam
removal, then OSHA would shut the building down. In fact, no
study by the ADA or NIDCR has been completed that specifically
and accurately addresses this issue. Yet, the ADA leads us to
believe that additional exposure to toxic mercury from these
procedures is not dangerous to our health. Mercury toxicity is
a retention toxicity that builds up during years of exposure.
The toxicity of a singular level of mercury is greatly increased
by current or subsequent, low exposures to lead or other toxic
heavy metals (12). Therefore, the damage caused by amalgams could
occur years after initial placement and at mercury levels now
deemed safe by the ADA.
Our ability to protect ourselves from the
toxic damage caused by exposure to mercury depends on the level
of protective natural biochemical compounds (e.g. glutathione,
metallothionine) in our cells and the levels of these protecting
agents is dependent upon our health and age. If we become ill,
or as we age, the cellular levels of glutathione drop and our
protection against the toxic effects of mercury decreases and
damage will be done. This is strongly supported by numerous studies
where rodents have been chemically treated to decrease their
cellular levels of protective glutathione and then treated with
mercury, always with dramatic injurious effects when compared
to controls. Therefore, published science indicates that mercury
toxicity is much more pronounced in infants, the very old and
the very ill.
A recent NIH study on 1127 military men showed
the major contributor to human mercury body burden was dental
amalgams. The amount of mercury in the urine increased about
4.5 fold in soldiers with the average number of amalgams versus
the controls with no amalgams. In extreme cases it was over 8
fold higher. Since the total mercury included that from diet
and industrial pollution are we to expect that this 4.5 to 8
fold average increase in mercury is not detrimental to our health?
Does this indicate that amalgams are a "safe and effective
restorative material"? Is the public and Congress expected
to be so naïve as to believe that increased exposure above
environmental exposure levels is not damaging? Then why are pregnant
mothers told to limit seafood intake when mercury exposure from
amalgams is much greater? Then why is the EPA pushing regulations
to force the chloro-alkali plants and fossil fuel plants to clean
up their mercury contributions to our environment? Obviously,
from this study most of the human exposure to mercury is from
dental amalgams, not fossil fuel plants. Yet, the FDA lets the
dental profession continue to expose American citizens to even
greater amounts of mercury. They do this by refusing to test
amalgam fillings as a source of mercury exposure. Also, remember
that the amalgam using ADA dentists are a major contributor to
mercury in our water and air through mercury leaving the dental
offices, and even when we are cremated.
"The ADA's Council on Scientific Affairs
1998 report on its review of the recent scientific
literature on amalgam states: "The Council concludes that,
based on available scientific information, amalgam continues
to be a safe and effective restorative material." and
"There currently appears to be no justification for discontinuing
the use of dental amalgam." What would you expect an
ADA Council to say? The ADA, as evidenced in the current letter
by the President of the ADA, only quotes and considers valid
the published research that supports their desire to continue
placing mercury containing amalgam fillings in American citizens.
When were dentists trained to evaluate neurological and toxicological
data and manuscripts? What is needed is an international conference
where both the pro- and anti-amalgam researchers show up and
present their data in front of a world-class scientific committee.
I would challenge the ADA to line up their scientists and supporters
to participate in such a conference. This could be held in Washington,
D.C. so the FDA officials could easily attend. Perhaps we could
persuade the FDA to sponsor such a conference. However, this
is unlikely since a recent written request to have a conference
to evaluate the safety of amalgams was rejected in a letter from
the FDA and signed by three FDA/ADA dentists who presented the
ADA line on this issue. Doesn't it seem a bit fraudulent to have
FDA/ADA dentists deciding on whether or not a safety study should
be done on mercury emitting amalgams being placed in human mouths
with the blessing of the ADA? This does seem like a conflict
in interest that Congress should address.
"In an article published in the February
1999 issue of the Journal of the American Dental
Association, researchers report finding "no significant
association of Alzheimer's disease with the number, surface
area or history of having dental amalgam restorations."
This research was lead by a dentist, Dr. Sax. It was submitted
to the J. of the American Medical Association and rejected. It
was then submitted to the New England Journal of Medicine and
rejected. It was then published in the ADA trade journal, JADA,
that is not a refereed, scientific journal. JADA is loaded with
commercial advertisements for dental products. They even called
a "press conference" announcing the release of this
article! Calling a press conference for a twice-rejected publication
that is to appear in a trade journal is playing politics with
science at its worst! At this press conference two of the authors
made unbelievable statements that were not supported by any of
the data in the article and conflicted with numerous major scientific
reports, including the 1998 NIH study (6). Some of these were
high-lighted in the side-bars of the ADA publication. I would
suggest that those concerned with this article visit Medline
and look at the publication records of the two individuals who
made these statements. Also, look at the three earlier excellent
publications in refereed journals by some of the other authors
showing significant mercury levels in the brains of AD subjects
compared to controls (14a,b, 15). However, put a dentist in charge
of the project and the data gets reversed!
Apply some common sense. The ancillary comments
by some of the authors and the results of the JADA publication
are in total disagreement with the vast majority of research
published that looks at elevated mercury levels in subjects with
amalgam fillings. For example, the NIH study on military men
discussed above showed a very significant elevation of mercury
in the blood that correlated with number of dental amalgams (6).
Another recent publication demonstrated elevated mercury in the
blood of living AD patients in comparison to age-matched controls
(10). These studies clearly show that there should be increased
mercury in your blood if you have amalgams and especially if
you have AD and amalgams (6,10). Does not the brain have blood
in it? This makes it a total mystery as to how could the authors
of the JADA article not find elevated brain mercury levels in
patient with existing amalgams and/or AD. Even cadavers have
brain mercury levels that correlate with the number of amalgam
fillings they had on death.
Further, if you are addressing the contribution
of amalgams to brain mercury and AD wouldn't it be important
to divide the AD and control subjects into those with and without
existing amalgams on death? In the JADA article this was not
done and represents a major research flaw! That this was not
done also arouses suspicion. I participated in submitting a letter
pointing out this flaw to editors of JADA but they refused to
acknowledge the letter and did not publish our comments. It is
my opinion that the entire situation around this singular supportive
publication of the ADA position on amalgams, brain mercury levels
and AD represents a weak attempt at controlling the mind-set
of well-meaning dentists, scientists, physicians and medical
research administrators. It definitely impedes honest scientific
debate. It also explains the cavalier attitude of the ADA and
NIDCR about elemental mercury exposure and toxicity when compared
to the more serious approaches taken by the EPA and OSHA.
With regards to the JADA article summary
that "no statistically significant differences
in brain mercury levels between subjects with Alzheimer's disease
and control subjects." Here I must quote Mark Twain
on honesty, "There are liars, damned liars and statisticians."
Comparing the level of mercury in the AD versus control alone
using straight-forward statistics previously showed a significant
difference on mercury levels in AD versus control subjects (14a,b,
15). However, there are anomalies, confounders and other factors
that can be considered in this situation, especially if you don't
like the initial results. This allows one to invoke a Bon-Feroni
statistical manipulation. With Bon-Feroni you include the comparison
of one pair of data (that may be statistically significantly
different taken alone, e.g. mercury levels in the brains of AD
versus control subjects) with several other pairs of data rendering
the difference statistically insignificant. One known weakness
of the Bon-Feroni treatment of several coupled pairs of comparisons
is that one very likely will miss a single comparison that is
significantly different, and clever people know this. It is my
opinion that application of the Bon-Feroni manipulation is what
happened in this JADA study that reversed the previous significance
of the mercury levels in AD versus control brain previously reported.
Research previously reported by some of the very same researchers
involved in the JADA study consistently indicated that mercury
levels were higher in AD versus age-matched control brains (14a,b,
15). Only when an ADA dentist became involved did the results
change to being insignificant. I think the data used in this
JADA article and funded by NIH needs to be re-evaluated by a
different statistician if we are to ever really know if the mercury
levels in the AD brains differed significantly from controls.
The letter from the ADA President then lists
four publications as proof of amalgams having no statistically
significant negative effects. Two of these were published in
Scandinavian Journals, another was a review of the literature
in a Dental Journal, and one was the JADA article mentioned above.
Sweden is well known to have lead the world in the restriction
and replacement of dental amalgams with non-mercury containing
materials. Forces are pushing hard to get the use of amalgams
accepted again in Sweden to eliminate this embarrassment to our
ADA. The current situation in Sweden and some other European
countries, Canada and Japan seriously questions the ADA contention
of amalgam safety. What if people in Sweden become healthier
Additionally, the studies quoted by the ADA
President were epidemiological studies. These are very complex
as many confounders are included which make finding a statistically
significant difference very difficult. So the results are negative,
nothing found, and not surprising. However, they are in disagreement
with numerous other similar reports and appear to be hand-selected
to support the ADA position. One has to wonder, since the ADA
President seemed to visit Swedish journals to support the ADA
position, how he missed the research of the Nylander group in
Sweden that showed increased mercury content in brains and kidneys
of humans in relationship to exposure to dental amalgams (17,18).
Also, the referenced studies in the ADA letter did not involve
neurotoxicity, autism or neurological disease---which is the
question at hand. Rather, they addressed fertility, reproduction
and other systemic illnesses. Could not the ADA find references
to focus on neurotoxiological studies? What about the 1989 study
that showed elevated levels of mercury in 54 individuals with
Parkinson's disease when compared to 95 matched controls (16)?
Further, one ought to consider who was doing these touted ADA
studies and any vested interest they may have in the outcome.
I am also aware of studies done in the U.S.A. by major research
universities that would disagree with the conclusions drawn by
the ADA on this subject yet these articles are not considered
in the ADA letter.
At the end of the last publication the quote
"Conclusions: No statistically significant correlation
was observed between dental amalgam and the incidence of diabetes,
myocardial infarction, stroke, or cancer." How does
this relate to an article published in the J. of the American
College of Cardiology where the mercury levels in the heart tissue
of individuals who died from Idiopathic Dilated Cardiomyopathy
(IDCM) contained mercury levels 22,000 times that of individuals
who died of other forms of heart disease? Where did this tremendous
amount of mercury come from? Even a Bon-Feroni manipulation could
not make this difference insignificant! Many who die of IDCM
are well-conditioned, young athletes who drop dead during sporting
events---and they live in locations and in economic environments
where sea-food is not a dietary mainstay. Perhaps the victims
of IDCM are within the ADA Presidents "handful of individuals
who are allergic to one of its components."
"The National Institute of Dental
and Craniofacial Research is currently supporting
two very large clinical trials on the health effects of dental
amalgam. Studies underway for several years each in Portugal
and the Northeastern United States involve not only direct
neurophysiological measures but also cognitive and functional
assessments." Do we really think that the NIDCR and
associated ADA personnel are going to deliver up a conclusion
to American parents saying "we put a mercury containing
toxic material in your child's mouth that lowered his/her I.Q.
and made him more susceptible to neurological problems in comparison
to the children whom we selected to not get exposed to this toxic
material"? It is my opinion that most bureaucracies don't
have a brain or a heart, but they do have a very strong survival
instinct. Therefore, the results presented from this study will
likely follow previously ADA supported research, i.e. no significant
Since the NIDCR started this project only
4 years ago one has to ask why it took so long for them to get
involved since the "amalgam wars" have been going on
for scores of years? Was it the overwhelming amount of modern
science showing mercury from amalgams being a major part of the
daily exposure that forced their hand and they had to develop
a defense? Would I trust the conclusions of this study without
knowing who put it together and who did the statistics? Not any
more than I trust the conclusions of the JADA article mentioned
in the ADA letter that stupendously concludes that mercury from
dental amalgams does not get into the brain.
As was proven by the tobacco situation, trying
to find any significant negative effect of one product (amalgams)
related to any disease through epidemiological studies is very
difficult and complex. To do this with mercury would be difficult
because of the synergistic effect two or more toxic metals or
compounds (e.g. cadmium from smoking) may have on the toxicity
of the mercury emitted from amalgams. For example, one publication
showed that combining mercury and lead both at LD1 levels caused
the killing rate to go to 100% or to an LD100 level (12). An
LD1 level is where, due to the low concentrations, the mercury
or the lead alone was not very toxic alone (i.e., killed less
than 1% of rats exposed when metal were used alone). The 100%
killing, when addition of 1% plus 1% we would expect 2%, represents
synergistic toxicity. Therefore, mixing to non-lethal levels
of mercury plus lead gave an extremely toxic mixture! What this
proves is that one cannot define a "safe level of mercury"
unless you absolutely know what others toxicants the individual
is being exposed to. The combined toxicity of various materials,
such as mercury, thimerosal, lead, aluminum, formaldehyde, etc.,
is unknown. The effects various combinations of these toxicants
would have is also not defined except that we know they would
be much worse than any one of the toxicants alone. So how could
the ADA take any exception, based on intellectual considerations,
to my contention that combinations of thimerosal and mercury
could exacerbate the neurological conditions identified with
autism and AD? Autism and AD have clinical and biological markers
that correspond to those observed in patients with toxic mercury
exposure. Why would the ADA take this position? I personally
feel like I have been in a ten year argument with the town drunk
on this issue. Facts don't count and data is only valid if it
meets the pro-amalgam agenda.
The ADA was founded on the basis that mercury-containing
amalgams are safe and useful for dental fillings. This may have
been an acceptable position in 1850. However, modern science
has proven that amalgams constantly emit unacceptable levels
of mercury. Especially as the average life span has increased
from 50 to 75-78 years of age where AD and Parkinson's become
prevalent diseases. The ADA can try to verify its position using
selected epidemiological studies. But the bottom line is that
amalgams emit significant levels of neurotoxic mercury that are
injurious to human health and would exacerbate the medical condition
of those individuals with neurological diseases such as ALS,
MS, Parkinson's, autism and AD.
I am hoping that the ADA sent this letter
to your committee and also placed it on the ADA web-site to indicate
that they are now willing for a wide-open discussion to take
place on the issue of dental amalgams. I, for one, would welcome
a major scientific conference on this issue. The ADA should feel
free to post my letter in response and address any issue they
feel that I am mistaken about. However, in closing I urge your
committee to push forward on the study of the potential dangers
of mercury in our dentistry and medicines. This includes mercury
exposures from amalgams, vaccines and other medicaments containing
thimerosal. The synergistic effects of mercury with many of the
toxicants commonly found in our environment make the danger unpredictable
and possibly quite severe, especially any mixture containing
elemental mercury, organic mercury and other heavy metal toxicants
such as aluminum.
Boyd E. Haley
Professor and Chair
Department of Chemistry
University of Kentucky
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