Mercury Exposure from Dental Amalgam and Chronic ...

Mercury Exposure from Dental

Amalgam and Chronic Fatigue

Syndrome - A Possible

Connection? Harald J. Hamre, G.P. 0510, Norway Adapted from Amalgam Qg S,ykdom (Dental Amalgam and Disease) by Harald Hamre, MD. Norway: 1993. An Eng/ish translation 0/ this book is planned.

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ental amalgam is a mix­ ture of metals, contain­ ing approximately 50 percent mercury com­ bined with silver, tin, copper and sometimes also zinc, indium, palladium or small amounts of cadmium. 1 Its widespread use in dentistry began in the USA in the 1830s and led to the controversy known as the "Amalgam War I" (ca. 1830-1856). The side effects of mercurial ointments, used against syphilis, were well-known. Oppo­ nents of amalgam claimed that its mercury content would be harmful to the teeth and oral cavity and could cause various general diseases. The defenders of amalgam argued that it was safe and cheap, thus offering the working classes an alternative to merely extracting decayed teeth. The technique of manufacturing and laying amalgam fillings was im­ proved and toward the end of the 19th century almost all opposition to the use of amalgam had ceased. In 1926 the German chemist Alfred Stock brought attention to the release of mercury from dental amalgam. 2 Stock had been mercury poisoned from occupational expo­ sure, but a toxicologist had advised hirn also to have his amalgam fillings removed. From 1926 to 1943 Stock published approximately 50

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scientific papers on dental amalgam and mercury. His work opened the "Amalgam War 11," resulting in a lively debate wh ich lasted through World War 11. Since the late I 970s, health effects from amalgam fillings have been debated, particularly in Swe­ den, but also in Germany, the USA) and other countries. Focus in this "Amalgam War III" has shifted from the well-known galvanic currents in the mouth caused by metals 4­ which particuIarly have been linked to Iocal oral symptoms 5- to the systemic effects of mercury released from amalgam.

Mercury Exposure {rom

Dental Amalgam The release of mercury vapor from dental amalgam is weIl docu­ mented. 6.JO People with amalgam fillings generally have a mercury vapor concentration 10 times higher than people without such fillings. Oxygen in the air probabIy reacts with metals in the fillings, forming an oxide film which limits the mercury disbursement. 11 However, this film is not very effective, as chewing gum, brushing teeth and drinking hot beverages all increase mercury release. In one of the best documented studies,9 chewing increased the intra-oral mercury concentration six-fold over unstimulated levels and 54 times the level in the control subjects without dental amalgam. Under experimental conditions, even electromagnetic fields from computer screens have

been shown to increase mercury vaporization from amalgam. 12 The World Health Organiza­ tion J3 (WHO) has summarized various attempts to calculate the daily retention (uptake minus excretion) ofmercury. They found that the daily retention from dental amalgam was 3-17 micrograms of mercury per day, while that from all other sources studied was only 2~ micrograms. These calculations onIy concern the uptake of inhaled mercury vapor and are based on the observation that 80 percent of inhaled mercury vapor is absorbed in the blood­ stream,14 while the remaining 20 percent is deposited in the respira­ tory airways and expired. However, mercury is also released from amalgam in the form of metallic ions and has been found in human saliva, gingiva, 15 oral mucosa, 16 enamel, dentin17,18 and tooth puIp.19 A direct uptake of mercury from the oronasal cavity into the brain through valve­ less veins has been postulated20 but not further investigated. Some animal experiments indicate a direct transport of mercury through peripheral nerves and into the central nervous system. 21 -24 Inorganic mercury is considered to be poorly absorbed after inges­ tion. However, the absorption of diluted mercury in the intestinal tract of subjects with amalgam has never been thoroughly evaluated. The daily fecal excretion of mercury is 20 times higher than the daily urinary excretion. 25 Methylation of inorganic mercury to methyl mer­ cury would increase the gastrointes­ tinal absorption, as 95 percent of ingested methyl mercury is ab­ sorbed. 26 In vitro, such methylation is catalyzed by the human normal gastrointestinal flora27 ,28 and sup­ pressed by antibiotics. 29 Mercury is retained in various organs, mainly in the kidneys, but also in the brain and endocrine glands. Human autopsy studies have revealed concentrations of 10-30 The CFIDS Chronicle • Fall 1994

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ;Ämal9am FilliV\9 5 nanograms mercury per gram of organ tissue in various parts of the brain and 20-800 nano grams mercury per gram of organ tissue in the renal cortex, with a statistically significant correlation between the measured mercury concentration and the number of amalgam fillings. 30 Significant correlations have also been observed between the number of amalgam fillings and mercury concentration in blood and urine. 13 Placement,lHl polishing14 and grindingl 5-40 of amalgam fillings leads to a manyfold increase in the measurable mercury exposure, which can last for days or months following treatment.

Blologlcal Effects o(Mercury Mercury' s effects on the bio­ chemicallevel have been studied extensively and include DNA damage;41 alteration of the structure of proteins; alteration of the trans­ port of calcium through calcium ';',;~.'

channels leading to disruption of the communication between cells;42 induction of free radicals;43.44 and inhibition of the antioxidant enzyme glutathione peroxidase. 4S Biological effects have usually been studied after short exposures (hours, days) to very high doses of mercury (micrograms, milligrams), rather than with the long-term, low doses from dental amalgam. How­ ever, exposure from amalgam fillings occurs without interruption for many years. Experiments using nanograms of mercury have dem on­ strated inhibition of granulocyte46 and lymphocyte47 function. One study found that 16 small amalgam fillings placed in the mouths of monkeys induced a significant increase in mercury- and antibiotic­ resistant bacteria in the oral and intestinal flora. 48 In another study, 12 amalgam fillings placed in sheep's mouths impaired their kidney function by 50 percent. 49

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,,' ' Mereury is a toxie material. That is a fact. However, the risks of amalgam fillings to humans have been debated ever since the material was introduced, as , Dr. Hamre notes in this article, and no real answers have been determined over the last 150 years. Most doetors will tell you that replacing your fillings will not guarantee any improvementin health unless you have a demonstrable allergy to mercury. And vapors released when removing mercury-containing fillings may injure some peopte ilprecautions (as Dr. Hamre indicates) are not carefully followed. Evenso, there seems to be compelling evidence that dentists should avoid using mercury-containing amalgam and other metals which increase mercury release (see "Pradieall\dvice" on page 47) when performing new deQ.tal work. Mercury is listedas a toxic chemical with reproductive hazards under' California's Proposition 65, which was passed in 1986. Proposition 65 mandates that manufacturers 01 toxie materials notify consumers of risks associated with their products. In December 1993 Jeneric/Pentron, Inc., one of the nation's largest manufacturers oi amalgam fillings, agreed to provide California dental offices with signs which SÜlte: "WARN1NG: This office U$e5 amalgam filling materials which contain and expose you to mercury, a chemicaJ known to the State 01 Ca/ifomia 10 cause birth defects and other reproductive hann. Please consull your dentist lor more information. " And mercury-containing amalgam has been bannedin Sweden and is no Ion ger used to treat tooth decay in

Norwegian children. 'Mercury has traditionally been used in amalgam fillings as a "'bonding agent" whi.c:h hold, allthe other metals together. However, new mercury-free amalgam filiingS have been developed which use new metal-fusing technology. There are alsoan'increasing number of long-Iasting non-metallic composite materials available tOdentists. Asmore alternatives to mercury fillings are made available, the 150-)'~r.:old debate over the safety of amalgam fillings may cease to be a healthcafe'lssu~,•.•

The CFlDS ChronicJe • Fall 1994

Mercury can induce so but also suppressSI autoimmune reactions in animals. The autoimmune reactions studied in mice and rats are not necessarily dose-dependent, but occur only in certain strains. A hypothesis currently being re­ searched in Sweden is that mercury can induce autoimmunity in humans with certain HLA-groups (geneti­ cally determined "fingerprints" on the surface of cells). In a preliminary study, there was a larger number of activated CD4+ cells with inter­ leukin-2 receptors and activated CD8+ cells with HLA-DR receptors within the group of 44 subjects with amalgam compared to the control group without amalgam. 52

Health Ef(ects Reponed After Amalgam Removal Aside from the undisputed, but very rare amalgam allergies in the orthodox sense53 and local reactions in the oral mucosa adjacent to amalgam fillings,S4 the major issue is whether amalgam fillings can cause general symptoms. The main evidence in favor of this hypothesis comes from a group of studies recording the improvement or disappearance of long-standing symptoms in 70-85 percent of the cases after amalgam removal. 55-62 A common phenomenon 51 which has been seen often in the author's clinical experience is the aeute occurrence/aggravation of symptoms hours or days after the removal of single amalgam fillings. Headache, dizziness, depression, museie and joint pains, tachycardia, diarrhea and chilis are reported. Occasionally, the patient is acutely confused and unable to find his way horne from the dental surgery. These reactions can hardly be psychogenic, as they occur after and not prior to or during the dental treatment. Apart from the side effects of anesthesia or the dental materials replacing the amalgam fillings, the only plausible explanation would be areaction to acute inhalation/ingestion of mer­

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Amalgam Fillit'\gs

.. The scientific community researching CFS seems to be relatively uninformed about the amalgam controversy, and, vice versa, amalgam researchers usually do not consider CFS in their published papers. Consequentially, very Iittle research into a possible connection has been done. " cury vapor/amalgam particles released during the grinding. 14-40 Discussion The referred amalgam removal studies have important weaknesses. Only three of them S6--S8 are prospec­ tive, Le., symptoms and signs being recorded before and after amalgam removal. The remainder are retro­ spective, recording the data only after treatment. This increases the risk ofthe data being incomplete or misleading: how weil does the patient remember his condition prior to treatment? None include a comparable control group to account for the placebo effect and spontane­ ous fluctuations ofthe symptoms. However, the reported effects of amalgam removal are consistent and substantial: most symptoms are cured or significantly alleviated in a percentage (70-85 percent) much higher than through placebo treat­ ment (usually 30 percent). Placebo effects are commonly short-Iived, whereas the reported effects have lasted more than two years.S4.SS.S7 As the criteria for inclusion in these studies were simply patients either A) seeking treatment from or being referred to individual dentists or B) reporting to a patient organization, they do not allow for any estimation of the frequency of systemic adverse effects from dental amalgam. Representatives of the dental profession have argued against the existence, or at least common occurrence,67,68 of such systemic effects (except for the rare amalgam allergy) because: • Epidemiological and clinieal studies have failed to demonstrate any correlation between dose (number of amalgam fillings69,70

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and mercury concentration in the blood'1 or urine 72) and symptoms. • Workers occupationally exposed to mercury generally have much higher mercury concentrations in their body tissues and fluids. 7J However: • Mercury-exposed workers represent only a segment of the general population and are exposed 7-8 hours a day, five days per week, whereas mercury exposure from amalgam is constant. • Blood and urine are poor indica­ tors of mercury exposure in critical organs, i.e., brain,14 endocrine glands or immune system cells. • Dose-effect correlations have less relevance if immunological reactions are involved. The WHO presently thinks it "not seientifi­ cally possible to set a level for mercury Ce.g., in blood or urine) below which mercury-related symptoms will not occur"13 [in individual cases]. • The safety of dental amalgam has never been proven in long-term clinical trials with control groups receiving different treatment. Research on CFS, Dental Amalgam. and Mercury

The overlap of symptoms between these amalgam groups and patients with chronic fatigue syn­ drome (CFS) is remarkable: 10 of the 11 symptom criteria ofthe V.S. Centers for Disease Control (CDC) diagnostic criteria for CFS6 J (low­ grade fever, sore throat, painful lymph nodes, generalized museie weakness, fatigue, headache, arthralgia, neuropsychological complaints and sleep disturbances)

are reported with variable frequency among the amalgam patients and the eardinal CFS-symptom ofchronic fatigue is usually the first, second or third most common symptom. Ofthe additional symptoms64 and signs6S associated with CFS anxiety, weight loss, intermittent tachycardia and various oral disturbances there is further overlap with the amalgam patients. Eight ofthe ll CFS symptom criteria are well-known symptoms ofmercury poisoning. 66 The scientific community researehing CFS seems to be relatively uninformed about the amalgam controversy and, vice versa, amalgam researchers usually do not consider CFS in their pub­ lished papers. As a consequence, very Httle research into a possible eonnection has been done. Before the CFS eriteria were established, a Swedish group7S investigated 27 patients with CFS-like symptoms: overwhelming fatigue (100 percent), malaise (96 percent), low-grade fever (85 percent), myalgia or arthralgia (81 percent), ete., inc1ud­ ing a tendency towards an aeute flu­ like onset of the symptoms. They examined 20 red and 20 white blood cells per person with PIXE (particle­ induced X-ray emission), and detected mercury in at least one of the cells in 81 percent of the patients and in none of the control group. whieh was matched for age, sex and socioeconomic status. In a preliminary Swedish study,S2 22 CFS-patients CCDC eriteria) differed from both a healthy control group of 12 subjects with amalgam dentures and a control group of 12 amalgam-free subjects with respect to eertain subgroups of T-Iymphocytes related to natural killer [celI] aetivity (CD11b, CD56, CD71 and CD57). Employing a recently-developed in vitro assay for deteetion of metal-specific memory lymphocytes, the same researehers found high lymphocyte reaetivity toward mercury and other metals in amalgam (and gold) fillings in a The CFlDS Chronicle • Fall 1994

___________________________ AmaI9cU'1'l Fill;"'9 s group ofCFS patients, as eompared to healthy individuals.76 Future studies should include a dental history, dental status, mereury measurements and - in selected groups - amalgam removal under controlled conditions.

Practical Aduice CFS patients interested in removing their amalgam should note the following: • Make sure your dentist is /amiliar with alternative jilling materials. Ifyou are seriously ill, it is advisable to consult a dentist with experience in the treatment of amalgam victim. For assistance in ehoosing a dentist, eontaet DAMS, Inc. (Dental Amalgam Mercury Syndrome), 7025 Osuna Blvd. NE, Albuquerque NM 87109-2325, Fax: 505/856-7878. • You are slrongly advised againsl removing more than 1 or 2 small jillings at a time, with an interval 0/4-6 weeks hetween each amalgam removal session. Removing all amalgam in a very short time is weil tolerated by most healthy people, but has repeatedly led to devastating, long-Iasting or even permanent disease in sensitive individuals. • Ifyou are planning to replaee amalgam with gold jillings, you are advised to wait be/ore inslalling gold unUI all the amalgam has heen removed. The combination of gold and amalgam or other dissimilar metals sub­ stantially increases the oral galvanism, or eleetric eurrent, wh ich again inereases amalgam corrosion17 and mereury release. Not infrequently, the onset of disease is preeeded by the inlay of a gold filling in a mouth with a number of amalgam fillings. • Mereury exposure during the grinding %ld amalgam ji/lings ean be redueed ifyour dentist applies a rubber dam around the looth, sprays cold water on the drill to reduee the temperature The CFlDS Chronicle • Fall 1994

3. ZiffS: The laxic lime bomb. Santa Fe: Aurora Press. and uses air suclion to remove 1986. mereury vapor. 4. Lain ES, Caughron OS: E1~trogalvanic pbenomena of the oral cavity caused by dissimilar metallic Iftroublesome symptoms are restorations. J Am Dem A.!:s 1936;23:1641-52. still present after amalgam grinding, 5. Mumford 1M: Electrolytic aclion in the mouth and its relalionship 10 pain. J Dem Res 1957;36:632-40. the following proeedures have been 6. Gay DD, CO!; RD, Reinhardl JW: Chewing releases reeommended - although none of mercury from fiIlings. Lancel S May 1979:985-6. 7. Sware CW, Pelerson LC. Reinhardl IW, Boyer DB, them has been evaluated through Frank CW, Gay DD, el a1.: The effcci of dental clinical studies: amalgams on mercury levels in expired air. J Denl Res 1981 ;60:1668-71. • Supplement the die! with vitamins 8. Patterson JE. Weissberg BO, Dennison PI: Mercury (E, C and the B vitamins), amino in human breath from dental amalgams. BI/li Environ Con/am Taxico/1985;34:459-68. acids (glutathione and methion­ 9. Vimy MI, Lom:heider FL: InlraoraI air mercury ine) and minerals (selenium, zine, released from dental amalgam. J Denl Res 1985;64:1069-71. magnesium) espeeially during the 10. Aronsson AM, Lind B, Nylander M, Nordberg M: last 4-8 weeks be/ore amalgam Dental amalgam IIIld mercury. Biol Melals 1989;2:25-30. removai. 78 11. Ferracane JL, Hanawa T, Okabe T: Effectiveness of • Aleohol ean reduce the uptake 0/ oxide films in reducing mercury release from amalgams. J Denl Res 1992;71(5):1151-5. mereury vapor up to 30 percenP9 12. Ortendal T, Högsledt P: Effekter pä amalgam probably through inhibition of the orsakade av magnet!li11 &.In bildskärmar. (EffeclS on amalgam caused by magnetic fields from video enzyme eatalase,80 which is screens.) Arbe/smiljöjondens SammOlljalmingar involved in the oxidation of 1524 (Reviews jrom lhe OCCllpalionaJ Medicine FOl/ndalion). Slockholm: Arbetsmiljöfonden, 1992. metallic mercury in red blood 13. lPCS, Environmental Health Cnlena 118./norganie cells and elsewhere. Alcoholics Mel'Cllry. Geneve: World Health Organizalion, 1992. have less mereury in the visual 14. Nielsen Kudsk F: Absorption of mercury vapor cortex of their brain than one from the respiralory ttacl in man. Acla Pharmacol Toxico/1965;23:2S0-62. would expeet from their dental 15. Reichmann P: LAMMS and lCP-MS deleclion of 81 amalgam status. A drink before dental metallic compounds in not-discolored human gingiva.J Dem Res 1992;71:5991 DR Abs1672. amalgam removal has been 16. Willershausen·ZOnnchen B, ZimmennannM, reeommended, but is often Defregger A, Schrame! P, Hamm 0: Queck­ siIberkonzentrationen der mundscbleimhaut bei precluded by alcohol intolerance. patienlen mil amalgamfllllungen.