, Volume 27, Issue 1, pp 19-24

First online:

Open Access This content is freely available online to anyone, anywhere at any time.

New science challenges old notion that mercury dental amalgam is safe

  • Kristin G. HommeAffiliated withInternational Academy of Oral Medicine and Toxicology
  • , Janet K. KernAffiliated withDepartment of Psychiatry, University of Texas Southwestern Medical CenterInstitute of Chronic Illnesses, Inc. Email author 
  • , Boyd E. HaleyAffiliated withDepartment of Chemistry, University of Kentucky
  • , David A. GeierAffiliated withInstitute of Chronic Illnesses, Inc.
  • , Paul G. KingAffiliated withCoalition for Mercury-Free Drugs (CoMeD)
  • , Lisa K. SykesAffiliated withCoalition for Mercury-Free Drugs (CoMeD)
  • , Mark R. GeierAffiliated withInstitute of Chronic Illnesses, Inc.


Mercury dental amalgam has a long history of ostensibly safe use despite its continuous release of mercury vapor. Two key studies known as the Children’s Amalgam Trials are widely cited as evidence of safety. However, four recent reanalyses of one of these trials now suggest harm, particularly to boys with common genetic variants. These and other studies suggest that susceptibility to mercury toxicity differs among individuals based on multiple genes, not all of which have been identified. These studies further suggest that the levels of exposure to mercury vapor from dental amalgams may be unsafe for certain subpopulations. Moreover, a simple comparison of typical exposures versus regulatory safety standards suggests that many people receive unsafe exposures. Chronic mercury toxicity is especially insidious because symptoms are variable and nonspecific, diagnostic tests are often misunderstood, and treatments are speculative at best. Throughout the world, efforts are underway to phase down or eliminate the use of mercury dental amalgam.


Mercury Dental amalgam Porphyrins Chronic mercury toxicity