This study shows that individuals with dental amalgam fillings who exhibit symptoms typical of chronic mercury poisoning, all have mercury vapour concentrations in their oral cavity far higher than acceptable levels and on average, higher than the maximum permitted levels for the industrial environment.

Results indicate that those patients with only amalgam filling, high concentrations of mercury vapour in the oral cavity, and who have also many amalgam surfaces, exhibit on average more symptoms than those with lower concentrations of mercury vapour and few amalgam surfaces.

The results indicate that the presence of symptoms is not solely dependent on the size of mercury dose.


Ever since the 1920s, it has been known that "silver"amalgam fillings liberate mercury vapour in concentrations regarded as harzardous. Professor Alfred Stock demonstrated this with an impressive accuracy, aspecially for that era.1.

Mercury is an unusual metal which is liquid at room temperature and which evaporates very easily. In the form of vapour, mercury is easily absorbed through the air passages and the mucosa into the blood which spreads it thoughout the body at high speed.2.3.

Mercury emerges in all tissues and organs. Examinations have shown that it passes the brain barrier easily, and comparable concentrations have been found in brain and muscular tissues.4.

Many scientific studies show that mercury vapour accumulates easily and dramatically in the muscular tissue of the heart, and that mercury is the most probable cause of many heart and vascular diseases.5.

In the case of pregnant women, mercury passes completely unhindered through the placenta to the embryo, and it has been shown that the concentration of mercury in the blood of an embryo can be up to 30 times higher than in the blood of the mother.6.

Gustav Drasch, the medical jurist and professor of toxicology at the University of Munich, has carried out new and impressive studies which show that the quantity of mercury in aborted embryos and dead infants corresponds to the number of amalgam fillings which the mother has.7.

Many crafts and industries have in the past, made use of the metal mercury or of easily vapourizing mercury combinations.

Within medicine, mercury and mercury combinations were used as treatment, disinfectant and preservatives, for instance against syphilis, in mercurochrome and in vaccinations.

Gradually, the use of mercury has been prohibited by law, as it is now realized that mercury is extremely injurious to living creatures even in extremely small quantities, and especially in its vapourized form.

In order to protect people against poisonous mercury vapours in the work place, maximum permitted levels have been set to control the amount of mercury which the air may contain before the authorities demand changes in working practices and special provisions using filters and exhaust mechanisms.

Here in Denmark, the maximum permitted level of mercury vapour has been set at 50 microgram mercury vapour per cubic metre air in a work area where people work 8 hours a day 5 days a week.

In Russia and Switzerland, the maximum permitted level has been set at 10 microgram mercury vapour per cubic metre. In Germany and U.S.A. it is 100 microgram per cubic metre air in a given work area.

A Health Canada report entitled "Assessment of Mercury Exposure and Risk from Dental Amalgam" was published on 27 Nov. 1995 in conjunction with the first " amalgam Stateholder Meeting" in Toronto.

This Risk Assessment report recommends the establishment of a "Tolerable Daily Intake (TDI)" for mercury vapor and suggest the number of dental amalgam fillings for various age groups that will not comprimise the TDI.

The tolerable daily intake (TDI) of 0.014 mcg Hg/kg body weight/day was proposed for mercury vapour, the principal form of mercury to which bearers of amalgam fillings are exposed.

The number of amalgam-filled teeth, for each age group, estimated to cause exposure equivalent to the TDI were: 1 filling in toddles; 1 filling in children; 3 fillings in teenagers; and 4 fillings in adult and seniors".8.

In its report on inorganic mercury, published in 1991, WHO states that, on the basis of many scientific studies, it is impossible to set a minimum risk level where no damages and symptoms of chronic mercury poisoning may occur.9.

In other words, we are officially advised to inhale as little mercury as possible, as some people exhibit symptoms from even very low concentrations of mercury in the inhaled air. According to WHO, the greatest source of mercury in the body is our amalgam fillings.9.

Officially, the attitude still prevails that mercury is so strongly bound in amalgam fillings that leakage is very minimal, and that it is almost impossible to measure. However, studies have shown, especially within the last 10 years, that free mercury may be seen perling on the surface of the amalgam fillings, and that high concentrations of mercury vapour can be measured in the oral cavity, especially after chewing food, and consuming hot or sour drinks.10.11

Methods and Result

All new patients suspected of chronic mercury poisoning caused by their amalgam fillings and who came to the clinic over a period of time, received (as usual) a thorough odontologic examination and anamnesis. In addition, they were all measured for mercury vapour concentrations in the oral cavity in microgram per cubic metre air.

The measuring instrument is a Jerome 413X from Texas Instruments which measures mercury vapour with the accuracy of 1 microgram per cubic metre air.

All patients filled out a questionnaire containing questions on 38 chosen typical chronic poisoning symptoms and complains. (see fig.1.)

103 individuals took part in the study of whom 72 were women and 31 men, aged from 26 to 79 years, with an average age of 47 years.

The 103 individuals of the study had on average 14 symptoms each.

The highest mercury vapour concentration in the oral cavity was measured at 329 microgram mercury vapour per cubic metre air, and lowest measurement was 3 microgram mercury vapour per cubic metre air.

The average concentration of mercury vapour in the group was 54.6 microgram mercury per cubic metre air

58 of the participants had between 25 and 75 microgram mercury per cubic metre air.

Those individuals who had only amalgam fillings and those who had high mercury vapour and many amalgam surfaces had, on average, more symptoms than those who had also gold/porcelain/metal and those with lower mercury vapour and few amalgam surfaces.


Those individuals with more than 50 microgram mercury per cubic metre air had on average 26.8 amalgam surfaces and 1.2 gold surfaces per person, and those with less than 50 microgram mercury per cubic metre had only 19.8 amalgam surfaces, but 1.8 gold surfaces per person.

amalgam surfaces per person was 22.5.

Apart from their amalgam fillings 24 individuals also had gold fillings, 2 had steel crowns and 24 had metal/porcelain crowns.


The 103 participants in this study had on average following symptoms expressed as a percentage.

Fig. 2.

                                                     Symptoms for all participants in the group.

                                                              Symptoms for those with more than 50 microgram mercury / m3.

                                                                      Symptoms for those with less than 50 microgram mercury / m3.

                                                                               Symptoms for those who had more than 21 amalgamsurfaces

                                                                                        Symptoms for those who had less than 21 amalgamsurfaces.

                                                                                                Symptoms for those who also had porcelain and guld.

                                                                                                        Symptoms for those who only had amalgam fillings

Symptoms / complains.

Allergy                                            36    34    37    38    34    35    35

Skin reaction                                   33    34    32    36    30    24    38

Bleeding gums                                 24    24    24    34    16    24    23

Tender teeth                                    37   34    40    36    39    30    43

Bad breath                                      29    37    32    28    30    19    35

Metallic taste                                   43    39    47    45    43    30    51

Blisters & sores                               30    27    32    32    29    24    32

Watery eyes                                    29    27    31    28    30    24    31

Sore throat                                      35    29    39    36    34    32    37

Facial tension                                   50   49    50    53    46    27    62

Nasal congestion                             33    37    31    30    36    21    40

Nasal discharge                               30    32    29    34    37    30    31

Bloating                                           60    51    66    55    64    58    43

Hunger pain                                     46    49    44    43    48    46    43

Poor appetite                                   12    15    11    11    14    14     8

Diarrhea                                           25    27    32    23    27    22   30

Constipation                                     33    39    31    34    34    31   41

Intestinal cramps                              38    49    32    38    39    46   24

Headache                                        53    54    53    53    54    43   58

Migraine                                          12    12    13    21    5      8     14

Fatigue                                            76    78    76    81    73    70    80

Poor concentration                          69    71    68    70    68    54    77

Poor memory                                  65    61    68    66    64    51    72

Irrational fear                                  36    37    35    21    39    30    40

Irritability                                        52    63    45    55    50    41    58

Depression                                     33    24    39    36    30    24   38

Insomnia                                        46   41    50    43    50    46    48

Dizziness                                        49    61    42    51    48    41    54

Muscle fatigue                                58    54    61    62    55    51    62

Muscle tremor                                33    37    32    34    34    30    35

Sciatic pain                                    38    39    37    34    41    43    35

Chest pain                                     22    20    32    21    23    21    23

Legs cramps                                  27    37    21    30    25    21    29

Joint pain                                       60    59    61    62    59    62    58

Cold hands-feet                             53    54    53    57    50    51    54

Heart problems                             14    10    18    11    18    19    12

Urinary syst.disorders                    19    20    19    23    16    27    14

Frequent infections                        19    17    21    21    18    16    22

The diagram (fig.2) shows that the most frequent symptoms experienced by more than 50 percent of the participants were : Fatique - poor concentration - poor memory - bloating - joint pain - muscle fatigue - cold hands and feet - irritability - and headache.

Those individuals with higher mercury vapour concentration than average, suffered more frequently from: instestinal cramps - irritability - dizziness - and leg cramps.

It seems that individuals with lower concentration of mercury vapour than average, more often get symptoms such as: Sore throat - depression - and chest pain.

For further information see the diagrams fig.2, for the effect of high or low concentration of mercury vapour on the average of various symptoms.

There is a small difference in the average number of symptoms (14.9 and 14.4) depending on the number of amalgam surfaces.

Those with many amalgam surfaces have on average, higher mercury vapour concentrations in the oral cavity than those with few amalgam surfaces.(See fig.3.)




It would seem that the number of individual symptoms, varies depending on the number of amalgam surfaces present.(See fig.2)

The frequency in occurrence of different symptoms varies widely, depending on whether the patients have amalgam fillings and gold/porcelain and other metal in the same mouth, or whether they have only amalgam fillings.

Individuals with only amalgam fillings have on average a much higher frequency of the following symptoms: Tender teeth - bad breath - metallic taste - facial tention - nasal congestion - bloating - instestinal cramps - headache - migraine - fatigue - poor concentration - poor memory - irrational fear - irritability - depression - dizziness - muscle fatigue - leg cramps and frequent infections.

Individuals with amalgam fillings and gold/porcelain and other metal in their mouth have, on average, a higher frequency of the following symptoms: Bleeding gums - diarrhea - constipation - sciatic pain - heart problems and urinary disorders.

The Mercury Vapour Measurement

All those who took part in this study had four measurements taken of the mercury vapour concentration at various places in the oral cavity. Each person had further measurements taken after ten minutes of chewing gum. The measurement showed that if they chewed on the fillings, the release of mercury vapour increased in most cases. This was expected, as this effect has been demonstrated in many studies..

This study was designed to find the approximate average mercury vapour concentration for each individual.

I therefore chose to use the highest of the four first measurements that was made before chewing as an acceptable measure for the average concentration of mercury vapour in the oral cavity.

Description of Symptoms

All of the 103 individuals who participated in the study filled in a questionare with 38 typical mercury poisoning symptoms. They were asked whether "they often suffer from the following symptoms and complains". The participants of the study had 1445 symptoms in all, or an average of 14 symptoms per individual.

Individuals with more than the average of 21 amalgam surfaces and more than 55 microgram mercury vapour per cubic metre air, which is the average measured on the 103 participants have, on average 15,2 symptoms.

Those with only amalgam fillings, had almost the same average number of symptoms, namely 15.7 per person. For those who had gold/ porcelain too, the average number of symptoms was 12,7.

Individuals with less than 21 amalgam surfaces, and less than 55 microgram mercury per cubic metre air, had an average of only 12,3 symptoms.

Apparantly, the number of amalgam surfaces and the amount of mercury vapour concentration seem to have a destinct influence on the number of symptoms. (See fig.1.)

There is a clear connection between the mercury vapour concentration and the number of amalgam surfaces, as can be seen from the reference line.

the correlation coefficient r = 0.24.

If you substract the 10 percent of the measured result that varies most from the reference line, the correlation is stronger (r = 0.47).



When the correlation between the mercury vapour concentration and the number of amalgam surfaces is not very clear, it may be due to the following circumstances :

1) that for more than 20 years an amalgam with 10 percent more copper has been used (High

Copper Amalgam). It is known from scientific studies that this type of amalgam releases

up to 50 times as much mercury and copper as types of amalgam used in the past.12.

Many individuals have had this type of amalgam, and it is impossible to see the difference

betwen the to type of fillings.


2) that one third, 37 of the participants of the study, besides having amalgam also have gold/

fillings/crowns or metal/porcelain crowns.

This mixing of various metals in the mouth is known to give added corrosion of the

amalgam fillings, which means that more mercury is released from the fillings, but mainly as

a product of corrosion and not as mercury vapour.13.


3) that some of the patients had activated their amalgam fillings just before we performed the

measurement, for instance by having brushed their teeth, or had a warm drink or by chewing

gum, which may have influenced the result of the measurement.14.

Using only individual symptoms gives a big difference in the number of symptoms depending on the size of the concentration of mercury vapour in the participants of the study, and of how many and what kind of metals they have in the teeth.

This study shows that individuals with high mercury vapour concentrations in the oral cavity also have the most symptoms including:: intestinal cramp - irritability - dizziness and leg cramps.

It also appears that those with amalgam fillings only, have far more tender teeth - bad breath - skin reaction - blister - and sores - metallic taste - facial tension and nasal congestion - bloating - intestinal cramps, compared with those who have also gold/porcelain/metal and also headache - migraine - fatigue - poor concentration - poor memory - irrational fear - irritability - depression and dizziness - mucle fatigue - leg cramps and frequent infections are more frequent with the participants who have only amalgam fillings.

Those who, besides their amalgam fillings also have gold/porcelain/metal in their teeth, seem to have as average a higher frequency of bleeding gums - diarrhea - constipation - sciatic pain - heart problems and urinary disorders.

Many studies have shown that metals in the oral cavity corrods one another, and that these corrosion products are harmful to some individuals.15.

Scientific studies show that, if an individual is exposed to mercury vapour from amalgam fillings through each breath times daily, this may result in many different symptoms, complains and illness. The mercury is quickly received through the lungs and is led by the blood to all organs of the body.

For example, the heart musculature is specially exposed as mercury quickly and dramatically accumulates in this important muscle. This may lead to destruction of areas of the heart muscle which may again lead to symptoms such as pain in the heart region, fatigue and other heart symptoms.

Some participants of this study have experienced these symptoms.

In many earlier published studies it has been shown that removal of all amalgam fillings results in a remarkable decrease in the number of symptoms, as 8-9 out of 10 symptoms get better or disappear.

Or to put it another way, individual symptoms are reduced from 60 - 100 % after one year ore more from the time of change. 20.21.

It is important to point out that though an individual may inhale relatively large quantities of mercury, this does not necessarily translate directly into injury..

There is an enormous difference in the resistance levels of different individuals, but inhaling mercury vapour will always be a hazard to ones health. 22.23.24.

Attempts have been made to set a safe minimum risk level for mercury vapour.

The Agency tor Toxic Substances and Disease Registry (ATSDR) of the U.S. Public Health Service has recently published a list of 275 of the most dangerous substances that represent of potential threat to the health. Mercury is one of these substances.

ATSDR has resently reduced the maximum recommended level daily chronic inhalation of metallic mercury vapour from 0.028 to 0.014 microgram mercury per cubic metre air per kilogram body weight. 25.


This study shows that the mercury vapour concentration in individuals with symptoms of chronic mercury poisoning is on average, 54.6 microgram mercury per cubic metre air and consequently above the maximum permitted limit for the working environment of 50 microgram per cubic metre air 5 days a week 8 hours a day - and far, far above the set maximum permitted level of 0.014 microgram mercury vapour per cubic metre air per kilogram body weight, comparable to one microgram for a person of 7o kilogram.

Furthermore, the study shows that on average there is a difference in the number of single symptoms in individuals with many amalgam fillings and high mercury vapour concentrations - compared with individuals with few amalgam fillings and lower vapour concentration.

Certain symptoms, for example bleeding gums - blister and sores - skin reaction - facial tension - metallic taste and some others seem to be more frequent than those who have many fillings, or only amalgam fillings.

Those who, besides the amalgam fillings, have also gold/porcelain or other metal in their teeth, more often experience.diarrhea or constipation

The results of the study indicate that the dosage of mercury acquired is not the only decisive factor concerning whether symptoms are experienced.

Other important factors include the presence of metals apart from amalgam, which type of amalgam is precent, length of time exposed to mercury, as well individual tolerance levels.

Additionally, symptoms which are promoted by these factors seem to differ widely.

The study demonstrates that metals - and particularly the amalgam used in dentistry to-day - are an important cause of increased mercury levels in the human body.

Results indicate that mercury poisoning from the amalgam fillings is widespread throughout the population.


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21. Lichtenberg, H: Elimination of symptoms by removal of dental amalgam from mercury poisoned patients, as compared with a control group of average patients. J.Orthomol. Med.(1993) Vol.8 No.3.

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25. USPHS, ATSDR. Toxicological Profile for Mercury: Update. TP-93/10, p 125.

Henrik Lichtenberg D.D.S.

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