Amalgam, which has been in use in dentistry for 150 years, consists of
50 % elemental mercury and a mixture of silver, tin, copper and zinc.
Minute amounts of mercury vapour are released continuously from
amalgam. Amalgam contributes substantially to human mercury load.
Mercury accumulates in some organs, particularly in the brain, where
it can bind to protein more tightly than other heavy metals (e. g.
lead, cadmium). Therefore, the elimination half time is assumed to be
up to 1 - 18 years in the brain and bones. Mercury is assumed to be
one of the most toxic non-radioactive elements. There are pointers to
show that mercury vapour is more neurotoxic than methyl-mercury in
fish. Review of recent literature suggests that mercury from dental
amalgam may lead to nephrotoxicity, neurobehavioural changes,
autoimmunity, oxidative stress, autism, skin and mucosa alterations or
non-specific symptoms and complaints. The development of Alzheimer's
disease or multiple sclerosis has also been linked to low-dose mercury
exposure. There may be individual genetical or acquired
susceptibilities for negative effects from dental amalgam. Mercury
levels in the blood, urine or other biomarkers do not reflect the
mercury load in critical organs. Some studies regarding dental amalgam
reveal substantial methodical flaws. Removal of dental amalgam leads
to permanent improvement of various chronic complaints in a relevant
number of patients in various trials. Summing up, available data
suggests that dental amalgam is an unsuitable material for medical,
occupational and ecological reasons.

PMID: 15789284 [PubMed - indexed for MEDLINE]

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