Mercury Toxicity

Mercury is... and always will be toxic to humans.

It seems silly to even question whether it is safe to place a material that contains, and releases mercury into the mouth and therefore the body.

Mercury amalgam fillings contain 50% mercury and, not surprisingly, are the biggest contributor of this most toxic material to humans.

Our position is simple. Mercury amalgam should not be used. Even when dentist uses the material on their patients, the left over material must be disposed of as toxic waste, by law. Therefore it seems a contradiction to suggest that putting it in patient's mouths is OK?

Its not, and there are much more biocompatible, non-toxic materials available.

Care should be taken when deciding to remove amalgam. Whenever amalgam is removed it is recommended by the NHMRC that rubber dam be used, additional suction and a special cutting procedure be employed.

Biocompatibility and Toxicity of Dental Materials

Biocompatible materials do not interfere with normal bodily functions.

The most commonly used dental material in the last 160 years is amalgam, which contains one of the most toxic substances, mercury. Dental amalgam contains 50% mercury, 20-35% silver, 6-15% copper, 8-15% tin and occasionally small amounts of zinc. In 1991 the World Health Organisation (WHO) included dental amalgam for the first time in its assessment of the human populations exposure to environmental mercury23 (Table 1). WHO also noted that for mercury vapour "a specific no-observed-effects level (NOEL) cannot be established" and that no level of mercury vapour has been found that could be considered harmless!

Exposure to mercury

Dental Amalgam 3.0 -17 mcg/day (Hg vapour)

Fish and Seafood 2.3 mcg/day (Hg Methyl)

OTHER FOOD 0.3 mcg/day (Hg Inorganic)

AIR and water negligible amounts.

Temperature, galvanic reaction and friction from chewing or clenching increase the rate of mercury release from amalgams. After chewing or increase in temperature, the levels of mercury vapour in the mouth remain elevated for up to 90 minutes. Mercury is released from dental amalgam as vapour, elemental mercury and particles. Mercury vapour is invisible, odourless and tasteless and 80% is absorbed through the lungs into the bloodstream where it undergoes rapid biotransformation to Hg+2. Methylation of mercury occurs in the body by the action of intestinal bacteria, and is readily absorbed through the intestinal lining.

Until the WHO 1991 report, Universities and Dental Associations around the world had contended that the mercury in dental amalgam was locked in to the material. If any were released it was in such small quantities as to be insignificant to health.

Significant studies have shown that:

• Major target organs for mercury released from dental amalgam is the kidney, liver and brain.24, 25.
• kidney function is impaired26
• heavy metal exposure from dental amalgam may contribute to immunological aberrations, which could lead to overt or increase auto-immunity27;
• mercurials, as well as other metals such as gold or palladium, induce strong lymphocyte proliferative responses in patients with oral or systemic symptoms28,
• Micro-mercurialism induced by a continuous supply of minute doses of mercury being released from dental amalgam fillings, is predominantly characterised by mental symptoms 29,30,31, 32,
• Mercury released from dental "silver" fillings provokes an increase in mercury-resistant and antibiotic-resistant bacteria in oral and intestinal floras of primates 33
• Mercury from amalgam is stored in the foetus and breast-feeding infant. 34 where it concentrates 35

Thousands of research articles have raised serious doubts about the use of mercury amalgam. Mercury is toxic and is slowly and continuously released from mercury amalgam. The number of amalgam fillings a patient has is proportionate to the amount of mercury stored in the tissues36. Mercury interferes with cellular metabolism by inactivating sulphydryl groups present in biologically active agents such as proteins, enzymes and enzyme inhibitors.

Mercury increases cell membrane permeability, poor cellular nutrition and interferes with enzyme function in the cell by combining with carboxyl, phosphoryl, amine and amide group. In the lungs mercury vapour tends to oxidise into free radicals i.e. Mercury ions reacting with haemoglobin (chronic fatigue), insulin (pancreas), thyroxin and coenzyme A (hypoglycaemia, haemoglobin formation)

The NHMRC recently published a patient information brochure37, which states that pregnant and breast feeding women, children and people with kidney disease should avoid amalgam filling. It also warns that the greatest exposure to mercury is when a filling is placed or removed and advises that these procedures be done using dental dam, additional suction and a particular cutting technique. Unfortunately the use of rubber dam is still not routine in all dental practices38, 39.

The most comprehensive and informative study to be done in recent years was undertaken by the Canadian Government, conducted and refereed by toxicologists40,41.. The reports showed that even on the most conservative assessment of mercury levels and health risks that for toddlers and children one amalgam filling would exceed a safe dose while teens could tolerate three filling and adults four before exceeding safe dose.

Holistic Approach - Removal of Amalgam Fillings

Extreme care in the removal of amalgam, by routine use of rubber dam and filtered air and the use of a biocompatible restorative material. Nutritional support during removal and detoxification.

The most commonly used alternative, composite fillings is inorganic filler 70-80% in a resin base. An assessment of the health risks of various components showed that the health risks are well below US EPA reference doses for mean and maximum exposure.

Find out more about removal of Amalgam Fillings by contacting us today.