At high levels mercury IS harmful to human health.   In fact at low levels mercury is harmful to human health. At low, CONTINUOUS exposure, mercury accumulates in the body.  The brain and nervous system are major areas of concern for the accumulation of mercury.  Mercury is Neurotoxic! In fact,  ALL levels of mercury are harmfull to ALL living organisms!

The ATSDR list mercury as the third most toxic substance known to man, after Arsenic and Lead.

Unlike Lead though, mercury is liquid at room temperature and vaporises atroom temperature and is thus more commonly bio- available than lead or arsenic.

Can mercury from fillings enter the body?

1.Very small amounts of mercury are released from the surface of dental amalgam fillings, mainly as mercury vapour.

1) There is no known level of mercury vapour which is regarded as SAFE (a no-observable-effects-level [NOEL] has never been demonstrated). To date there is not one agency in the world including the USEPA, FDA, and ATSDR nor the NHMRC who have shown a safe minimum level of mercury vapour. 

The use of the words "very small amounts" implies a harmless nonexistant level.  Health Canada attacked the Canadian Dental Association for making similar comments:

Canadian Dental Association:
Q. Is the mercury which is released from fillings absorbed into the body?

A. Yes, but in extremely small amounts, i.e. in MILLIONTHS of a gram (this is very small amount, 0.000001 grams.)

Dr Tobin's Response:
"This answer is rather condescending and insulting to the intelligence of readers. By emphasizing only how small a microgram is it implies that a microgram of toxic material could not be harmful. What is significant is not now many zeroes there are in a microgram, but how many micrograms of mercury are released by and compared to the number of micrograms required to cause illness. The fact is that a level of only one hundred millionths of a gram (only 0.0001 gram) of mercury per gram of Creatinine in urine is considered to indicate clinical mercury poisoning."

Mercury is released continuously from amalgam, mainly in the form of mercury vapour, which is considered one of the most toxic and most bioavailable forms.  80% of inhaled vapour is absorbed through the lungs. [ii]

Early symptoms of low-level mercury poisoning are characterised by sub-clinical (no clinical symptoms are visible) neurological (effecting the nervous system) symptoms.  It is nonsense to think the dental profession does not know this. Even the New York State Dental Journal (1979) state:

The symptoms of mercury poisoning from chronic inhalation develop gradually and thus, may be difficult to notice. With the exception of tremor, the symptoms may be ignored by the victim or attributed to other causes. This lack of awareness is particularly likely in the case of erethism, a condition characterized by; irritability, outbursts of temper, excitability, shyness, resentment of criticism, headache, fatigue, and indecision.

2 .....In this way, some mercury can reach the rest of the body and accumulate in certain organs, particularly the kidneys.

2) Mercury is a cumulative toxin.  It accumulates and stays in the body.  Although highest levels are found in the kidneys, the other main organ for the accumulation of mercury is the brain.  Mercury readily crosses the blood brain barrier and remains in the brain.  Mercury is neurotoxic.  Its most widely known damage is thus in the central and peripheral nervous systems.  Alzheimer's Disease and many other serious neurological diseases are strongly related to mercury^lxii .

The mention of mad hatters in the NHMRC article (point 3 of what are the health effects?)  must surely indicate that this information is known to the NHMRC.

3. However, the mercury levels involved are very low, so the amount of mercury absorbed into the body is very small.

3) This statement ignores the toxicity of mercury. For example a speck of plutonium is small but it will kill within a few days. To say that mercury vapour levels are low without taking into account its toxicity is, at best, misleading and at worst, deceiving.

Research has shown that over 80% of the inhaled mercury vapour is absorbed into the body via the lungs. Where is the NHMRC's evidence that small levels of mercury vapour are safe when ATSDR lists mercury vapour as one of the most toxic substances known to man? Interestingly, Canada Health (the Canadian equivalent of the NHMRC) have fully endorsed the 1995 Richardson report [iii] which clearly indicates that

1  Filling  in  Toddlers; 
1  Filling  in  Children; 
3  Fillings  in  Teens;
4  Fillings  in  Adults  and Seniors

provides the equivalent amount of mercury which the USEPA has set as its Tolerable Daily Intake-TDI .  More fillings will of course result in exceeding these TDI levels.

Intra-oral mercury vapour levels  are reported in the order of 200 times greater than that accepted by the ATSDR .

The ATSDR MRL for inhalation exposure to metallic mercury vapour is 2x10⁵ mg Hg/m³ ( 0.02 mcg Hg/m³) and the MRL for chronic inhalation exposure to metallic mercury vapour is 1.4x10⁵ mg Hg/m³ (0.014 mcg Hg/m³). These standards are both well below (by more than 5000 times) exposure levels to mercury vapour that have been well documented to emanate from amalgam dental fillings, even in the absence of stimulation. [iv]

Mercury vapour concentrations in the mouth of someone with amalgam fillings have been shown to be between 30 and 150mcg/m3. [v] ^{, [vi] , [vii] , [viii] , [ix] , [x] , [xi] , [xii] , [xiii]}

4. The amount of mercury released from fillings is greatest when fillings are being inserted or removed.

4)   The amount released during insertion or removal is significant and although the increase in mercury exposure is only transient, it can be more than enough to top the balance of people who are already sensitized and poisoned by mercury.  This is really an added insult to the already overloaded patient because mercury is released continuously from amalgam for the ENTIRE LIFE of the amalgam.

For this reason it is critical that correct removal procedures be followed and in fact that no amalgam should ever be placed in teeth. Apart from insertion and removal, eating, chewing, grinding, and drinking hot drinks will cause an increased release of mercury from amalgam.  After such stimulation the levels remain elevated for up to 90 minutes. [xiv] ^{, [xv]}

What is dental amalgam?

1. ....generally made up of mercury, silver and tin with small amounts of copper and zinc.

1) Even here the NHMRC cannot openly acknowledge that the bulk of a dental amalgam, is mercury, (about 50% of it in fact), with the rest being made up of all the other materials. Half of every amalgam filling is mercury, which continually leaks out and vaporizes over the ENTIRE LIFE of a filling. The ONLY way not to be exposed from this source is to not have amalgam fillings. Research has clearly shown that the mercury levels in people without amalgams, or who have had their amalgams removed, are significantly lower than those people WITH amalgams in their mouths.

WHO in 1991 stated clearly that dental amalgam is the greatest single source of dietary mercury to the general population.

2. The use of amalgam for dental work is declining.....

2) ANY use of amalgams represents a deliberate use of a material which is known to be the major source of mercury vapour exposure in human beings. Current dental materials technology is such that there is not one use for amalgams which cannot be satisfied by the clinically competent use of other and better alternatives.

In 2003, the Swedish Government stated that;

"With reference to the fact that mercury is a multipotent toxin with effects on several levels of the biochemical dynamics of the cell, amalgam must be considered to be an unsuitable material for dental restoration. This is especially true since fully adequate and less toxic alternatives are available."

What are the health effects?

1. High levels of mercury are harmful to human health. ......, producing signs such as mood swings, memory loss and development of tremors.

1) This statement is factually wrong because it is, in fact, low levels of mercury vapour which will produce signs such as mood swings, memory loss and development of tremors.  These are the early symptoms of low-level long term mercury poisoning - NOT the late ones, and they are not the symptoms seen in high level mercury poisoning.  High level poisoning is accompanied with rapid kidney failure.

2. In rare cases, a person may be allergic to mercury.

2) Peer reviewed published research has reported allergy levels of 5%‑8% (Rudner,) 27% (Djerrasi & Berova),  2%‑10.8 % (White & Brandt),  31%, 27%, 32%, 39% (Miller et al), 11.3% (Brun),  9.6 % (Nebenfuher et al), 13% (Sato et al)  [xvi] , [xvii] , [xviii] , [xix] , [xx] , [xxi]  

These are NOT small figures.  Assuming that only half of the Australian population have amalgam fillings we could conservatively expect that between  475,000 and  3,705,000 people are sick as a direct result of allergy to amalgam.

In the past the ADA have made allegations that less than one percent of the population is allergic to mercury.  They have never been able to substantiate this claim with any references.

The AMerican Dental Association have now reviewed this figure and claim that 3% of the population is 'allergic' to amalgam.

Even Caulk Co, the manufacturers of the Dispersalloy brand of amalgam, warn: "Allergic reactions that may occur in previously exposed persons include dermatitis, encephalitis, and death.

Unfortunately true allergy is only one of the immune effects of mercury Ð there are many others. [xxii] ^{, [xxiii]}

3. The phrase 'mad as a hatter' came about because the hat makers of the 19th century were exposed to high levels of mercury,.......

3) Dental personnel are exposed to exceptionally high levels of mercury vapour.  Evidence exists which shows significant health problems in dentists and dental nurses.  Dentists have one of the highest suicide rates of any profession. [xxiv] Dentists also have twice the rate of Glioblastoma (a type of brain cancer) than the rest of the population. [xxv] The authors of this study also state In the group of dental personnel, the effect of their own amalgam fillings on mercury concentrations....was as important as their occupational exposure to mercury.

Dentists also show evidence of subtle pre-clinical changes in behaviour associated with mercury exposure:

functions related to complex attention, psychomotor task, mood. [xxvi] ^{, [xxvii]}

Shapiro, et al. and Ship II, et al.   reported the relation between cumulative exposure to mercury and chronic health impairment. Of 298 dentists, 30% of the high mercury dentists had polyneuropathies. No polyneuropathies were detected in the control group. The high mercury group had mild visuographic dysfunction;  they also had more symptom- distress than did the control group. [xxviii]

There are many studies demonstrating that female dental personnel suffer dramatically from exposure to mercury in the dental environment. One such states:

Female dentists had a higher rate of spontaneous abortions then a control of female medical personnel or the rest of the population. 

The Peri-Natal Mortality Rate for the female dentists was significantly higher than for the rest of the population  - 19.5 / 1000 as compared to 7.5 / 1000 [xxix]

Unfortunately the problem does not stop with the dental nurse but is passed on to the offspring:

"rates of spontaneous abortion or non-congenital abnormalities in children during this period, were higher in respondents exposed to high levels of mercury in the dental environment than those exposed to low levels". This is published in the Journal of the American Dental Association Vol 122 August 1991.  It was written by Irwin Mandel DDS., Assoc. Dean for Research School of Dental and Oral Surgery Colombia University New York.

Another study reported a high frequency of adverse events of pregnancy among dental staff and learning deficit disorders in children of mothers having been exposed to mercury. [xxx]

The United States Environmental Protection Agency stated:

Women chronically exposed to mercury vapour experienced increased frequencies of menstrual disturbances and spontaneous abortions.

A high mortality rate was observed among infants born to women who displayed symptoms of mercury poisoning. [xxxi]

Is dental amalgam likely to affect me?

1. Different people have different tolerances to chemicals in the environment; however, in the opinion of the World Health Organization the levels of mercury exposure from amalgam fillings do not affect general health.

1) There has never been a level of mercury exposure set which is regarded as safe. A NOEL for mercury does not exist!  What is their reference for this comment?  Authoritative bodies such as the American NIH and even the NHMRC inquiry acknowledged that there were no studies which even looked at the issue.

2. ..... There is no reliable evidence that people with such fillings have a greater risk of ill health than people without amalgam.

2) The Absence of Evidence is NOT Evidence of Absence.  This is particularly pertinent when, as mentioned above, it has been acknowledged that virtually no studies have been done which even look at this issue.

3. A very small number of people may experience local side effects due to an allergic reaction to dental amalgam, causing irritation in the tissues surrounding the tooth.  However these local effects appear quickly, and can be recognised and treated.

3) The chances of any dentist recognising mercury allergy if it presented are extremely low. No training is given in this area, nor is it written about or discussed. Again, no reference is given to support this assertion. The fact is that any problems experienced are likely to be presented to a medical practitioner who is also very unlikely to recognise it as a low level mercury toxicity problem.

Local reactions DO NOT necessarily appear quickly and the only 'treatment' is to remove the caue. ie. remove the amalgam.

Local reactions are NOT the only affect on the immune system.  See www.melisa.org to gain an understanding of how mercury and other heavy metals can instigate a variety of auto immune diseases.

The medical profession, as well as the dental profession, are also almost certainly unaware that mercury from amalgam has been shown to cause an increase in mercury-resistant and antibiotic-resistant bacteria in the human body [xxxii] .  Antibiotic resistance has become a major medical public health concern and limits the effectiveness of antimicrobials.  The authors of the research which showed this noted that since dental amalgam is a greater source of mercury exposure for humans than any other non-occupational source (including food), it is likely that dental amalgam mercury is a selective agent which increases the prevalence of plasmid-associated mercury and antibiotic resistances in the oral and intestinal bacteria of humans.

Caulk Co., the manufacturers of Dispersalloy, state in the MSDS for this product: 

Exposure to mercury may cause irritation to skin, eyes, respiratory tract and mucous membrane. In individual cases, hypersensitivity reactions, allergies, or electrochemically caused local reactions have been observed. Due to electrochemical processes, the lichen planus of the mucosa may develop.

Mercury may also be a skin sensitizer, pulmonary sensitizer, nephrotoxin and neurotoxin......Allergic reactions that may occur in previously exposed persons include dermatitis, encephalitis, and death.

Putting the issue in perspective

1. Of the mercury found in the body, less is likely to have come from dental amalgam than from other sources.

1)  This statement is blatantly false! It has neither a reference nor any credibility.

WHO Criteria 118 - Environmental Mercury 1991

Between 3-17 times more mercury is absorbed from dental amalgam as compared to all other sources combined including seafood.

ATSDR  Elemental Mercury and Inorganic Mercury Compounds: Human Health Aspects (No 50) - Exposure to elemental mercury by the general population and in occupational settings is primarily through inhaling mercury vapours/fumes.

Dental amalgam constitutes a potentially significant source of exposure to elemental mercury, with estimates of daily intake from amalgam restorations ranging from 1 to 27 µg/day....

This ATSDR quote is from the very document used by the NHMRC in this pamphlet - Reference No 3.

Professor Drasch, Professor of Forensic Medicine at Munich, says:  Hg found in tissues of individuals with amalgam fillings derive mainly from these fillings and not from other theoretically possible sources.^xliii   (Hg is the Scientific notation for mercury.)

2. Mercury is present at low levels in our environment as a naturally occurring element in air, water and food.

2) Again the use of the words low levels, without any quantification and without any particular reference.  This would imply that the same low levels exist in the environment as in a mouth full of amalgam filled teeth. Mercury vapour levels in the mouth can be quantified and usually far exceed environmental levels.

Just because mercury is a 'natural' element and it IS found in nature, does NOT make it safe.  Arsenic, lead, plutonium, uranium and many other NATURAL substances are deadly.

3. Mercury in food, particularly in fish, is often in a form that can be easily absorbed by the body (in contrast to the mercury in dental amalgam).

3) There is no doubt that organic forms of mercury are readily absorbed.  This has been known for years.  It is amazing that the NHMRC suggest that elemental mercury (that which comes from amalgam) is not readily absorbed, particularly when they are referencing their position with the ATSDR paper which clearly states the opposite of what they are saying: 

For elemental mercury, the main route of exposure is by inhalation, and 80% of inhaled mercury is retained......Elemental mercury is lipid soluble and easily pene­trates biological membranes, including the bloodÐbrain barrier. Metabolism of mercury compounds to other forms of mercury can occur within the tissues of the body.

It has been known for some time that mercury can be converted to organic mercury in the intestinal tract of human beings. [xxxiii] ^{, [xxxiv]}   More recently a study has been published which demonstrates that elemental mercury from dental amalgam can be converted in the mouth to organic mercury.  The authors conclude:

Our results are compatible with the hypothesis that amalgam fillings may be a continuous source of organic mercury, which is more toxic than inorganic mercury, and almost completely absorbed by the human intestine. [xxxv]

4. The use of dental amalgam has been recommended to be phased out in Scandinavia and other parts of Europe, once satisfactory alternative materials become available. The reason for this was mainly concern over the release of toxic substances into the environment rather than concern about potential health effects for the individual.

4) This statement borders on the incredible suggesting that human beings are in some way separate from the environment.  Especially in terms of mercury derived from dental amalgam, it is the human being who is the first in line of the environment.  See reference xxxix in the next section.

Why is it that the environment should be protected if not for the sake of preserving life and health of all sentient beings who live on this planet?

The truth is that mercury from dental amalgam is a MAJOR source of mercury to the environment.

Mercury and the environment

1 Human activities since the start of the industrial age (eg mining, burning of fossil fuels and solid waste incineration) have resulted in additional release of mercury into the environment³.....  As mercury moves up the food chain it becomes more concentrated.

1) This is the only place in the pamphlet that cites the ATSDR document.  The rest of the ATSDR document seems to have been ignored.

It has been known for many years that crematoria release huge amounts of mercury into the environment.  Estimates indicate that each chimney releases about 11Kg mercury per year. [xxxvi] ^{, [xxxvii] , [xxxviii]}  

If the NHMRC are so concerned about the environment why have they still not imposed a requirement that all crematoria use mercury collection devices.  Surely this must be regarded as industrial exposure with environmental and health risks. 

Mercury released from amalgam in living people is also a major concern:

These results demonstrate that humans, especially in populated areas, can be a significant source of mercury pollutants. As a consequence of mercury release, bacteria may acquire mercury resistance, as well as resistance to other microbial agents. [xxxix]

2. Dental amalgam adds to the level of mercury in the environment when wastes from dental offices are not disposed of properly, and through cremation, which vapourises the mercury in amalgam fillings (although mercury vapour collectors are now often used at crematoriums to prevent this)

2)  Dental offices are significant contributors of mercury into the environment.  Why has the NHMRC not set guidelines for the compulsory use of mercury separators in dental surgeries?  It is a shame that they forgot to mention that once the human is no longer alive the amalgam in the mouth of that dead human is a serious TOXIC WASTE.

Pregnancy

1  During pregnancy, placement of new amalgam fillings or removal of old ones is not recommended, because the level of mercury in the blood tends to rise briefly in these situations. The mercury can cross the placenta and enter the bloodstream of the fetus^4,5.

1) There is no doubt that placement and removal of amalgam produce high levels of mercury but low levels of mercury are released from amalgam continuously.

The levels of mercury in the foetus and new born are directly proportional to the number of amalgams in the mother s mouth. 

These results came from autopsy studies on foetus and new born children many of whom died from Sudden Infant Death Syndrome. [xl] ^{, [xli]}

Women of child bearing age and younger should not have amalgam in their mouths!

Studies on sheep have shown that the mercury is stored in all parts of the body of the foetus including the developing central nervous system and pituitary gland. [xlii] The authors state: "We conclude that Hg released from dental amalgam tooth fillings will begin to selectively accumulate in maternal and fetal tissues soon after amalgam placement. .... Amalgam restorations are a source of continuous Hg exposure to both mother and fetus. In view of the experimental evidence presented herein, continued employment of dental amalgam as a tooth restorative material in pregnant women and children should be reconsidered."

Another study states:

... inorganic mercury found in tissues of people with amalgam fillings, derive mainly from these fillings and not from other theoretically possible sources. [xliii]

2  There is no scientific evidence of any link between amalgam use and birth defects or stillbirths. However, current thinking is that it is better to avoid dental work involving amalgam when possible during pregnancy, unless the effects of avoiding treatment could cause greater problems, eg the loss of a natural tooth.

2)  This statement is sadly incorrect and misleading. [xliv] ^{, [xlv] , [xlvi] , [xlvii] , [xlviii] , [xlix] , [l] , [li]}   It is clear that mercury is embryotoxic, teratogenic and mutagenic.  The dates of these references make it abundantly clear that this information has been around for a very long time. 

Lets also look again at what Caulk Co say about their amalgam product side effects:

The use of amalgam is contraindicated:

• In proximal or occlusal contact to dissimilar metal restorations.
• In patients with severe renal deficiency.
• In patients with known allergies to amalgam.
• For retrograde or endodontic filling.
• As a filling material for cast crown.
• In children 6 and under.
• In expectant mothers.

Caulk Co go on to say:

Intrauterine exposure may result in tremors and involuntary movements in the infants. Mercury is excreted in breast milk. Paternal reproductive effects and effects on fertility have been reported in male rats following repeated inhalation exposures.

Ivoclar (another amalgam manufacturer) go further and contraindicate the use of amalgam in pregnant and lactating women.

More recent studies indicate that:

Mercury vapor released from the amalgam fillings in pregnant rats was distributed to maternal and fetal organs in dose‑dependent amounts of the amalgam fillings. [lii]

In studies on animal offspring in utero exposed to mercury vapor, behavioral changes, such as radial arm maze, morris maze and lever‑press durations, are observed when the levels of mercury vapor exceed the threshold limit value. [liii]

Breastfeeding

Women who are breastfeeding should also avoid having amalgam fillings inserted or removed, because mercury can be passed to the baby through breast milk.        Of course, there are some situations during pregnancy or breastfeeding where dental work using amalgam might be necessary, and there is no scientific evidence that this will cause harm.

Again it is well known that mercury in all forms will be carried through the breast milk to the developing infant.

The higher Hg burden of infants' tissues from mothers with dental amalgam, as reported previously, must be explained (1) by a prenatal transfer of Hg from the mother's fillings through the placenta to the fetus, followed by a  redistribution of this Hg in the body of the newborn, and ( 2) an  additional burden via breast milk. [liv]

Of course there is a high level of exposure to mercury during placement or removal of amalgam BUT there is also a high level of mercury in the breast milk directly from the amalgam which is already present in the mother's mouth. It would thus be advisable for all women of child bearing age and younger not to have amalgam in their mouths to start with.

Intrauterine exposure may result in tremors and involuntary movements in the infants. Mercury is excreted in breast milk. [lv]

Children

Amalgam is now generally avoided for filling children's teeth. Growing children tend to be more sensitive to the effects of exposure to any chemical substance in their environment. Several of the new tooth‑coloured materials are suitable for use where cavities are small, as they often are in children.

Amalgam is still being used in many, if not most, school dental services throughout Australia. 

Amalgam is still used by the majority of paediatric dentists. Amalgam restoration of deciduous (milk) teeth is still being taught at most university dental schools.

Amalgam is routinely placed in children's teeth in dental surgeries throughout Australia partly because the dental authorities still promote the false notion that there is no suitable alternative for large cavities.  Suitable alternatives have been available for many years! Why continue exposing  the most sensitive members of the population to one of the most toxic substances known to man?

Kidney disease

Because high levels of mercury exposure may affect the kidneys, people with kidney disease may be more concerned than others to minimise exposure to mercury.

As mentioned earlier, High Level Mercury Poisoning is accompanied with Kidney Failure.

Low levels of mercury will have a dramatic effect on kidney filtration function.  Severe Renal Dysfunction is cited by Caulk Co. as a contraindication (ie not recommended).

Ivoclar go much further in their contraindications! They say their amalgam is not only contraindicated for patients with severe renal deficiency but for all patients suffering from a reduced kidney function.

Sheep studies have found a 50% reduction in kidney filtration rates after the placement of dental amalgam fillings. [lvi]

No reference is made in the NHMRC pamphlet about the effects of mercury in relation to:

Health effects on dental personnel [lvii] ^{, [lviii] , [lix] , [lx] , [lxi]}

Central nervous system - so numerous it would fill pages just to give all references

Mercury causing identical changes in the brain as is found in the brain of Alzheimer's Disease [lxii]  

Intelligence in children [lxiii]

Periodontal disease [lxiv]

Immune function [lxv] ^{, [lxvi]}

Auto Immune Diseases [lxvii] ^{, [lxviii] , [lxix]}

Endocrine function [lxx]

Should amalgam fillings be replaced?

1   There is no support in the scientific literature for the idea that the mercury released from amalgam fillings is harmful to an individual's health.

1) Mercury from dental amalgam is a cumulative poison.  The longer you are exposed to it, the more will accumulate in your body!  Mercury may not cause a specific disease, but it does cause mercury poisoning, which IS characterised in the largest array of diseases and syndromes known.

Mercury released from dental amalgam fillings is mainly in the form of vapour and as mentioned previously, 80% of inhaled mercury enters the blood and the body. 

Again from the ATSDR document (reference 3 of the NHMRC pamphlet) available at http://www.who.int/pcs/cicad/summaries/cicad_50.html:  

"Neurological and behavioural disorders in humans have been observed following inhalation of elemental mercury vapour, ingestion or dermal application of inorganic mercury-containing medicinal products, such as teething powders, ointments, and laxatives, and ingestion of contaminated food. A broad range of symptoms has been reported, and these symptoms are qualitatively similar, irrespective of the mercury compound to which one is exposed. Specific neurotoxic symptoms include tremors, emotional lability, insomnia, memory loss, neuromuscular changes, headaches, polyneuropathy, and performance deficits in tests of cognitive and motor function.

Although improvement in most neurological dysfunctions has been observed upon removal of persons from the source of exposure, some changes may be irreversible.

Acrodynia and photophobia have been reported in children exposed to excessive levels of metallic mercury vapours and/or inorganic mercury compounds. As with many effects, there is great variability in the susceptibility of humans to the neuro­toxic effects of mercury.  

The primary effect of long-term oral exposure to low amounts of inorganic mercury compounds is renal damage. Inorganic forms of mercury have also been associated with immunological effects in both humans and susceptible strains of laboratory rodents, and an antibody-mediated nephrotic syndrome has been demonstrated through a variety of exposure scenarios." [lxxi]

2  There is no scientific evidence showing that general symptoms are relieved by the removal of amalgam restorations ²

2) The NHMRC statement is clearly incorrect.  There is ample evidence which suggests that removing dental amalgam will reduce the body burden of mercury to pre-amalgam levels. 

In fact as part of creating their 2002 document the NHMRC called for their own new risk assessment ot be done.  It is clearly stated in section 8 of the executive summary of the Risk Assessment conducted on behalf of the NHMRC.

“Amalgam removal has been shown to be effective in reducing mercury levels to the levels of those in people without amalgam fillings.”

The first step to detoxify anyone is to first remove them from the source of the poison!

3. In fact, there are disadvantages to having amalgam fillings replaced ‑ replacement can be expensive; it almost always causes more of the natural tooth to be lost; and, mercury levels in the body rise immediately after amalgam fillings are replaced due to the manipulation of the amalgam. Alternative materials such as gold, ceramics or composite resins (plastics) require more of the tooth to be removed. Composite resins are also more prone to wear so they usually do not last as long as amalgam fillings.

3) It seems that the NHMRC need to take further advice on the material aspects of dental amalgam.

Dr. Harold Loe, the Director of the National Institute of Dental Research (NIDR),  stated in the September, 1993 edition of "Dental Products Report":

"That first filling is a critical step in the life of a tooth. Using amalgam for the first filling requires removing a lot of the tooth substance, not only diseased tooth substance but healthy tooth substance as well. So, in making the undercut you sacrifice a lot, and this results in a weakened tooth. The next thing you know the tooth breaks off, and you need a crown. Then you need to repair the crown...and so it continues to the stage where there is no more to repair and you pull the tooth. With the first filling you should do something that can either restore the tooth or retain more healthy tooth substance. Use new materials-composites or materials you can bond to the surface without undercuts. You can do this with little removal of the tooth substance so that the core of the tooth is still there." 

4  If you decide to have amalgam fillings replaced, your exposure to mercury can be reduced by using a rubber shielding device called a 'dental dam' and having extra suction during the removal. Dentists can also cut away, rather than drill out the amalgam filling, to help reduce exposure to mercury. Check that your dentist uses these measures before undertaking dental amalgam procedures.

4) If a rubber dam should be used during removal, why does the NHMRC not recommend it be used during placement when it says that mercury exposure is highest during removal AND placement? How does the NHMRC recommend that patients protect themselves from the continuing mercury vapour exposure which occurs 24 hours per day, 7 days per week, Or from the spikes in mercury vapour release, which can last up to 90 minutes, whenever someone eats or has a hot drink?

Amalgam removal protocols have been in place for many years but are routinely ignored by the dental profession.  I would like to know what the NHMRC considers to be sufficient protection.  Why does the NHMRC NOT advise dentists to use similar protective measures when they work daily with amalgam?

5   The decision to replace amalgam fillings is an individual one, and you should make it in consultation with your dentist. If you feel that you need further information after reading this leaflet and talking to your dentist, it may be a good idea to seek a second opinion.

5)  All patients have the right to be fully informed about any material or device which is to be implanted into their bodies.  Without full information it is not possible to make informed decisions.  In this regard the advice given in this statement by the NHMRC is misleading rather than informative as the NHMRC does not cite any alternate sources of information.

Most dentists are unaware of the dangers that they place themselves, their staff and their patients in when using amalgam.  Most dentists are themselves seriously affected by the mercury from amalgam. These effects include an impairment of cognitive understanding.  It is like setting the fox to gaurd the chickens.

Further information

Further information on the effects of amalgam fillings and their benefits and disadvantages can be found on the World Health Organization website http://www.who.int/ncd/orh

Also see the submission presented to the NHMRC by ASOMAT 1998 (www.asomat.org)

Instead of the URL presented here, I would suggest that you just go to the home page of the WHO and start your own search on amalgam and mercury.

Further information is available at many web sites and from many organisations.   Many are listed on the 'links' page.

Source References

1.         ADA Council on Scientific Affairs. Dental amalgam: update on safety concerns. journal of the American Dental Association. 1998 129:494-503.

2.         World Health Organization. Consensus statement on dental amalgam, 7 March 1997. Geneva: WHO, 1999.

3.         ATSDR. Toxicological Profile for Mercury. U.S. Department of Health & Human Services, 1999.

4.         Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment. Statement on the Toxicity of Dental Amalgam. Department of Health, United Kingdom, December 1997.

5.         Ad Hoc Working Group. Dental Amalgam. A report with reference to the Medical Devices Directive 93/42/EEC. European Commission, 1998.

No 3 ATSDR  is the only reference used here which has any scientific credibility.  As demonstrated above, this one reference alone disagrees with many of the statements made by the NHMRC.

The Australian and the American Dental Associations are NOT scientific organisations but trade organisations.    The objectivity of the publications of the dental associations on this issue is, unfortunately, quite suspect.

The World Health Organization Consensus statement on dental amalgam,   7 March 1997, is without an author and has never been endorsed by the WHO.  In fact it is a document written in conjunction with the FDI - another dental trade organisation. In the words of Dr Boyd Haley:

"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?

Interestingly, no mention is made of the position statement of Canada Health 1996:

Dentists should provide their patients with sufficient information to make an informed choice regarding the material used to fill their teeth, including information on the risks and benefits of the material and suitable alternatives.

The advantages and disadvantages of dental amalgam

In many respects, amalgam is an excellent filling material, because:

     It is reasonably priced.

      It is highly durable - apart from gold and some of the new ceramics, amalgam is the best material for teeth that are subject to considerable force during chewing and therefore a lot of wear (such as molars). Any replacement weakens the natural tooth that is being filled, so the longer a filling lasts, the better.

       It is pliable when first mixed and can be moulded into a tooth cavity - reducing the amount of natural tooth that needs to be removed in order to fit the filling.

The reality is that many dentists, particularly those who no longer use amalgams, would disagree completely with that statement. The newest composite resins have properties which make them a more than adequate alternative, and in a number of respects a much better alternative, especially in the area of minimal tooth preparation and bonding to undermined tooth structure. Evidence exists that teeth can be cracked by amalgams, presumably due to expansion of the amalgam over time. Many dentists would assert that there are no situations at all, ever, which cannot be dealt with using non-mercury based alternatives. One of the main difficulties here is that amalgams are relatively easy to use but the alternatives are more technique sensitive and require a higher skill level to manage correctly.  This is surely a compelling argument to increase skills through better teaching at the undergraduate level and at the post graduate level,  rather than dumbing down to the lowest common denominator.

Dr. Harold Loe, the Director of the National Institute of Dental Research (NIDR), wrote in the September, 1993 edition of "Dental Products Report":

"That first filling is a critical step in the life of a tooth. Using amalgam for the first filling requires removing a lot of the tooth substance, not only diseased tooth substance but healthy tooth substance as well. So, in making the undercut you sacrifice a lot, and this results in a weakened tooth. The next thing you know the tooth breaks off, and you need a crown. Then you need to repair the crown...and so it continues to the stage where there is no more to repair and you pull the tooth. With the first filling you should do something that can either restore the tooth or retain more healthy tooth substance. Use new materials-composites or materials you can bond to the surface without undercuts. You can do this with little removal of the tooth substance so that the core of the tooth is still there." 

In 1995 the editor-in-chief of Quintessence  (Volume 26, Number 3,1995), Dr Richard Simonsen wrote:

Amalgam should never be used as a restorative material in paediatric dentistry.

Amalgam should never be used as a first time restorative material.   

Why?  

Because better alternatives are available.  Move Over Amalgam - At Last

Another fact is that research has clearly shown that when amalgams are placed in teeth as fillings, then within a relatively short time, weeks not months, mercury which was present in the amalgam can be detected in virtually every other part of the body Ð brain, kidney, lungs, heart, etc. [lxxii] ^{, [lxxiii]}

It has been conceded in dental articles that if amalgam was introduced today, as a new material, it would have no hope at all of passing safety requirements and as such would have no hope of being introduced onto the market due to the high levels of mercury released. The only reason amalgam is still available is that it was grandfathered in and not subject to the same health standards as newer materials. With today's knowledge how can this situation still be acceptable?

Alternatives to amalgam have been around for a long time. 

Why is the NHMRC still endorsing its use today?

Glossary

ADA