Mercury in medicine

Banned mercury medicines are also found in Historic Uses of Mercury.

Mercury has antiseptic properties, so it has been used medicinally.  It is also used in dental amalgam because it bonds with silver to make a pliable and durable filling material. 

Dental amalgam

Dental amalgam fillings are about 40% mercury by weight. According to national and Washington data, much of the mercury that was being released from sewage-treatment plants was coming from the dental industry, specifically  wastewater contaminated with spent amalgam fillings and scrap amalgam.

Mercury Amalgam and Other Dental Office Wastes contains information on the Best Management Practices and history of the Memorandum of Understanding.

Mercury in Sewage Sludge/ Biosolids offers information on the success or reduction efforts.


Thimerosal, an organic mercurial compound, has been and is used in a variety of medicines, because of its antiseptic properties.  These products include vaccines, cosmetics, eye drops and saline solution.  The Material Safety Data Sheet for Thimerosal states:

"The substance may be toxic to kidneys, liver, spleen, bone marrow, central nervous system. Repeated or prolonged exposure to the substance can produce target organs damage. Repeated exposure to a highly toxic material may produce general deterioration of health by an accumulation in one or many human organs."

Look for Thimerosal-free products.

Related information

About Dental Amalgam Fillings at the Food and Drug Administration

Mercury in the Environment is at the Washington State Department of Health