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Mercury and MS – Summary and References

Multiple Sclerosis and Mercury Exposure
Summary and references

Multiple Sclerosis (“MS”) was first commonly identified in the 19th century during the time in which mercury/silver fillings came into common use. In the early part of the twentieth century, MS was known as the “faker disease.” 1 Unpublished anecdotal evidence indicates that a significant number of, but certainly not all, MS victims who have their mercury/silver fillings removed resolve (spontaneous remission) or improve gradually.  By 1993, forty-two MS victims had filed adverse reaction reports with the FDA.  Four of these were cured and twenty-nine improved.  There is toxicological evidence that mercury poisoning victims (from sources other than fillings) and multiple sclerosis victims share similar symptoms.  The Encyclopedia of Occupational Health and Safety discusses the symptoms of chronic mercury poisoning, in part, as follows:
Nervous system involvement may occur with or without gastrointestinal symptoms, and may evolve in line with two main clinical pictures: (a) fine-intention tremor reminiscent of that encountered in persons suffering from multiple sclerosis.

The most frequently encountered symptoms resemble those presented by persons with multiple sclerosis except there are no nystagmus and the two conditions have a different serology and different clinical courses. 2


In 1966 Baasch 3 concluded, based on sometimes severe neuroallergic reactions in acrodynia (pink disease)  and his own observations of neurologic patients, that multiple sclerosis was an adult form of acrodynia (pink disease) and a neuroallergic reaction, in most cases, caused by mercury from amalgam fillings.   Baasch demonstrated in great detail that facts concerning the geographical and age distribution, pathological development, and symptomatology of MS were all consistent with amalgams being the primary cause of the disease.  He reported several specific cases and cited ongoing studies that showed cessation of progression and improvement of resolution of MS after removal of amalgam fillings.


In a very detailed study, Craelius in 1978 4 showed a strong correlation (P<0.001) between MS death rates and dental caries.   The data demonstrated the improbability that this correlation was due to chance.  Numerous dietary factors were ruled out as contributing causes.


A hypothesis presented in 1983 by T. H. Ingalls, M.D. 5 proposed that slow, retrograde seepage of mercury from root canals or amalgam fillings may lead to multiple sclerosis in middle age.  He proposed a correlation of unilateral multiple sclerosis symptomatology with ipsilateral amalgam-filled teeth.  He also re-examined the extensive epidemiological data that show a linear correlation between death rates from MS and numbers of decayed, missing, and filled teeth.  Ingalls  suggested that investigators studying the causes of MS should carefully examine the patients’ dental histories.6  Furthermore, Dr. Ingalls’ hypothesis included other environmental exposures to mercury.  In 1986, he published data supporting his hypothesis that clearly demonstrate endemic clustering of MS in time and space over a 50-year time span that could be directly correlated to exposure to mercury.7  Another study (Ahlrot-Westerlund 1987) found that multiple sclerosis patients had eight (8) times the normal level of mercury in their cerebral spinal fluid as compared to neurologically healthy controls.8


In a 1990 study, the University of Aarhus, Denmark, Department of Neurobiology, conducted an experiment in which three vervet monkeys received occlusal amalgam fillings, three others maxillary bone implants of amalgam, and three untreated monkeys served as controls, in order to trace possible accumulations of mercury.  One year later, tissue sections from different organs were subjected to silver amplification by autometallography and analyzed at light and electron microscopial levels. It was found that amalgam fillings (total 0.7-1.2g) cause deposition of mercury in the following tissues: spinal ganglia, anterior pituitary, adrenal, medulla, liver, kidneys, lungs, and intestinal lymph glands.  In the monkeys with maxillary silver amalgam implants (total .1-.3g), mercury was found in the same organs with the exception of the liver, lungs, and intestinal lymph glands.  Organs from the three control animals were devoid of precipitate.  These results strongly support what has been suggested previously– that dental fillings in primates cause absorption of mercury released from amalgam fillings through the lungs and the intestinal tract, and that mercury is distributed to most organs and will eventually be found in the central nervous system.  (The presented data also show that silver released from the corroding filling is not absorbed.) 9

In a 1998 study, Dr. Svare and associates analyzed for its mercury content, the expired air of a group of 48 persons, 40 with and eight without dental amalgam restorations, before and after chewing .  Expired air samples were collected in polyethylene bags, and a known quantity of each was pumped into the mercury detector for measurement.  The results showed that subjects with dental amalgams had higher pre-chewing mercury levels in their expired air than those without amalgams.  After chewing, these levels were increased an average of 15.6-fold in the former and remained unchanged in the latter group.  It was therefore concluded that in situ dental amalgams can indeed increase the level of mercury in expired air.  10

A paper written in 1994 by Dr. Siblerud of the Rocky Mountain Research Institute, Inc., investigated the hypothesis that mercury from silver dental fillings (amalgam) may be related to multiple sclerosis (MS).   It compared blood findings between MS subjects who had their amalgams removed to MS subjects with amalgams.  MS subjects with amalgams were found to have significantly lower levels of red blood cells, hemoglobin and hematocrit compared to MS subjects with amalgam removal. Thyroxine levels were also significantly lower in the MS amalgam group and they had significantly lower levels of total T Lymphocytes and T-8 (CD8) suppressor cells.  The MS amalgam group had significantly higher blood urea nitrogen and lower serum IgG.  Hair mercury was significantly higher in the MS subjects compared to the non-MS control group.  A health questionnaire found that MS subjects with amalgams had significantly more (33.7%) exacerbations during the past twelve months compared to the MS volunteers with amalgam removal.  11

An article developed by the MELISA Foundation in March of 2005, noted that MS is caused by the erosion of myelin, a substance which helps the brain send messages to the body.  Metal particles entering the body can bind to this myelin.  For those who are hypersensitive, this myelin-metal bond comes under attack from the immune system.  In such cases, the progression of MS can be halted by removing the source of the metal.  The role of myelin is one of the few facts on which those who study MS are able to agree.  The MELISA Foundation has developed what they believe is a breakthrough in understanding in MS: the link between metal allergy and the erosion of myelin .  They believe that they have also been able to prove that the myelin erosion can be halted if the source of the allergy is removed.  Hypersensitive reactions are triggered by metal particles entering the body of a person allergic to the metal in question.  These particles then bind to the myelin, slightly changing its protein structure.  In hypersensitive people, the new structure (myelin plus metal particle) is falsely identified as a foreign invader and is attacked; an autoimmune response.  Arrows point to the “myelin plaques” in the brain, common in patients with MS.  Such plaques can be the result of metal allergy.  Already, the MELISA Foundation has seen patients with MS make a partial, and, in some cases, a full recovery by removing the source of metal – often dental fillings. 12

Mercury has been documented to accumulate in the very areas of the nervous system from which most dramatic clinical symptoms of MS originate.  Specifically, motor neurons accumulate more Hg than sensory neurons, and motor symptoms are seen to predominate over sensory symptoms in MS.  Although more research needs to be done in this area, these results suggest dental mercury exposure from amalgams, as well as from any other chronic low-grade mercury exposure, must be given very serious consideration as possibly playing a role in the etiology of MS in such patients and more likely is the major cause of most MS.  Genetic variability and individual ability to excrete mercury probably plays a role. 13

In conclusion, the causation of MS is probably multi-factorial.  Mercury is certainly one cause and probably the major cause of this disease.


1. Scientific American, September 1996, page 252

2. Encyclopedia of Occupational Health and Safety, (3rd revised edition, 1983).Parmeggiani, L., technical editor, pp. 1334-53

3. Baasch, E. Theoretische Ueberlegungen zur Aetiologie der Sclerosis multiplex. Die Multiple Sklerose eine Quecksilberallergie? Schw. Arch. Neurol. Neurochir. Psychiat. 98: 1-18 (1966).

4. Craelius, W. Comparative epidemiology of multiple sclerosis and dental caries. J. Epidemiol. Comm. Health 32: 155-165 (1978)5

5. Ingalls, TH. Epidemiology, etiology and prevention of multiple sclerosis, hypothesis and fact. Am J. Forensic Med. Pathol. 4: 55-61 (1983).6

6. Ingalls, TH. Triggers for multiple sclerosis. Lancet xx: 160 (1986).7

7. Ingalls, TH. Endemic clustering of multiple sclerosis in time and place, 1934-1984. Am J. Forensic Med. Pathol. 7: 3-8 (1986).8

8. Ahlrot-Westerlund, B. Multiple sclerosis and mercury in cerebrospinal fluid. Second Nordic Meeting on Trace Elements in Human Health and Disease, Odense, Denmark, 17-21 August, 1987.

9. Danscher, G., et al. Traces of mercury in organs from primates with amalgam fillings. Exp. Mol. Pathol. 52(3):291-9 (1990).10

10. Svare, C, et al. The effect of dental amalgams on mercury levels in expired air. J Dent Res. 60: 1668-1671 (1981).

11. Siblerud, RL, et al. Evidence that mercury from silver dental fillings may be an etiological factor in multiple sclerosis. Sci Total Environ. 142:191-205 (1994).

12. Stejskal, J, Stejskal, VD. Role of metals in autoimmunity and the link to neuroendocrinology. Neuroendocrinology Letters, 20:351-364(1999).13 Ely, JT, et al. Urine mercury in micromercurialism: bimodal distribution and diagnostic implications. Bull Environ Contam Toxicol. 63:553-9 (1999).



Mercury and MS

from Mutter, J.  Is dental amalgam safe for humans? The opinion of the scientific committee of the European Commission. Journal of Occupational Medicine and Toxicology 2011, 6:2

A 7,5-fold increased level of mercury was found in the cerebrospinal fluid (CSF) of MS patients [208]. It would be difficult to speculate that the presence of this increase in the CSF would not at least exacerbate the problems associated with MS or any other neurological disease. The prevalence of MS has been shown to be correlated with the prevalence of caries [209,210] and the prevalence of amalgam [211,212]. Several MS epidemics occurred after acute exposure to mercury vapor or lead [213]. In animal models inorganic mercury caused a loss of Schwann cells which build the myelin sheaths and stabilize the axons of neurons [214]. Autoimmune pathogenesis, including antibodies against myelin basic protein (MBP), can be provoked by mercury and by other heavy metals [148].

MS patients who had their amalgam fillings removed showed fewer depressions, less aggression and less psychotic and compulsory behaviors when compared to a group of MS patients with amalgam fillings [215]. They also had significantly lower levels of mercury in blood [216]. After amalgam removal, pathological oligoclonal bands in the CSF disappeared in MS patients [217]. Removal of dental amalgam also led to a recovery in a significant proportion of MS patients [147].

A retrospective study on 20,000 military individuals revealed a significantly higher risk for MS in individuals with more amalgam fillings [218]. This risk was underestimated, because the study cohort which was selected by means of medical examination consisted exclusively of individuals with good health at the time of joining the military [218]. Another problem occurring in some studies is the absence of documentation of the dental status before or at the time of the onset of multiple sclerosis. In spite of these limitations [219] a reanalysis found a 3.9- fold increased risk for multiple sclerosis in individuals with amalgam compared to individuals with no amalgam.

A recent systematic review also found an increased risk for MS caused by dental amalgam in spite of the fact that most studies did not use proper amalgam-free controls [220].


208. Ahlrot-Westerlund B: Mercury in cerebrospinal fluid in multiple sclerosis.
Swed J Biol Med 1989, 1:6-7.

209. Craelius W: Comperative epidemiology of multiple sclerosis and dental caries.
J Epidemiol Comm Health 1978, 32:155-165. Publisher Full Text

210. McGrother C, Dugmore C, Phillips M, Raymond N, Garrick P, Baird W: Multiple sclerosis, dental caries and fillings: a case-control study.
Br Dent J 1999, 187:261-264. PubMed Abstract | Publisher Full Text

211. Baasch E: Theoretical considerations on the etiology of multiple sclerosis. Is multiple sclerosis a mercury allergy?
Schweiz Arch Neurol Neurochir Psychiatr 1966, 98:1-19. PubMed Abstract

212. Ingalls T: Epidemiology, etiology and prevention of multiple sclerosis. Hypothesis and fact.
Am J Forensic Med Pathol 1983, 4:55-61. PubMed Abstract | Publisher Full Text

213. Ingalls T: Endemic clustering of multiple sclerosis in time and place, 1934-1984. Confirmation of a hypothesis.
Am J Forensic Med Pathol 1986, 7:3-8. PubMed Abstract | Publisher Full Text

214. Issa Y, Watts D, Duxbury A, Brunton P, Watson M, Waters C: Mercuric chloride: toxicity and apoptosis in a human oligodendroglial cell line.
Biomaterials 2003, 24:981-987. PubMed Abstract | Publisher Full Text

215. Siblerud RL: A comparison of mental health of multiple sclerosis patients with silver/mercury dental fillings and those with fillings removed.
Psychol Rep 1992, 70:1139-1151. PubMed Abstract | Publisher Full Text

216. Siblerud RL, Kienholz E, Motl J: Evidence that mercury from silver dental fillings may be an etiological factor in smoking.
Toxicol Lett 1993, 68:307-310. PubMed Abstract | Publisher Full Text

217. Huggins HA, Levy TE: Cerebrospinal fluid protein changes in multiple sclerosis after dental amalgam removal.
Altern Med Rev 1998, 4:295-300.

147. Prochazkova J, et al: The beneficial effect of amalgam replacement on health in patients with autoimmunity.

Neuro Endocrinol Lett 2004, 25:211-218. PubMed Abstract OpenURL

218. Bates M, Fawcett J, Garrett N, Cutress T, Kjellstrom T: Related articles, health effects of dental amalgam exposure: a retrospective cohort study.
Int J Epidemiol 2004, 33:894-902. PubMed Abstract | Publisher Full Text

219. Bates MN: Mercury amalgam dental fillings: an epidemiologic assessment.
Int J Hyg Environ Health 2006, 209(Suppl 4):309-316. PubMed Abstract | Publisher Full Text

220. Aminzadeh KK, Etminan M: Dental amalgam and multiple sclerosis: a systematic review and meta-analysis.
J Public Health Dent 2007, 67:64-66. PubMed Abstract | Publisher Full Text