http://www.ncbi.nlm.nih.gov/entrez/utils/lofref.fcgi?PrId=3400&uid=15789284&db=pubmed&url=http://www.thieme-connect.com/DOI/DOI?10.1055/s-2005-857962
Abstract
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, particulary 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 susceptilities 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.
*NOTE* Most European countries have banned the use of dental amalgam at some point in the early-mid 90’s. The ADA meanwhile continues to insist there is no danger from the continued use of amalgams here in the US, including putting them in very young children and pregnant women. Some researchers specializing in toxic metals suggest that dental amalgams are the single biggest exposure risk for Americans, to a much greater degree than the mercury emissions from coal-fired plants which ends up in the fish we may eat.