Human Health Risks from Dental Amalgam Mercury Fillings
All silver-colored fillings are dental amalgams, and each and every one of these fillings is comprised of 45%- 55% mercury. (2) Although a number of other countries have banned or limited their use, dental mercury amalgams are currently used on about 45% of direct dental restorations worldwide,(3) including in the USA. (4)
Mercury is continuously emitted from amalgam fillings, and it is absorbed and retained in the body, particularly in the brain, kidney, liver, lung, and gastrointestinal tract. (5) The output of mercury can be intensified by the number of fillings and other activities, such as chewing, teeth-grinding, and the consumption of hot liquids. (6) Mercury is also known to be released during the placement, replacement, and removal of dental mercury amalgam fillings. (7)
Scientific studies have documented the potential risks these fillings pose to human health:
1) The General Population:
Mercury in amalgam fillings has been scientifically linked to a number of health conditions. Individual response to mercury varies, and some of the factors known to potentially impact those exposed to mercury include their allergies, diet, gender, genetic predispositions to adverse reactions from mercury, the number of amalgam fillings in the mouth, and concurrent or previous exposures to other toxic chemicals such as lead (Pb). Scientific studies have identified dental mercury as a potentially causational or exacerbating factor in the following conditions:
Allergies, especially to mercury
Amyotrophic lateral sclerosis (Lou Gehrig's disease)
Autism spectrum disorders
Autoimmune disorders/ immunodeficiency
Chronic fatigue syndrome
Complaints of unclear causation
Oral lichenoid reaction and oral lichen planus
Psychological issues such as depression & anxiety
Symptoms of chronic mercury poisoning
2) Pregnant Women and Children:
Scientific studies have documented the devastating impact mercury can have on pregnant women and children, and mercury from dental amalgam fillings in mothers has been recognized for its potential risk to fetuses and children who are being nursed. For example, higher numbers of maternal fillings have been correlated with higher levels of mercury in breast milk. Additionally, authors of a study from 2011 cautioned: “Changes in dental practices involving amalgam, especially for children, are highly recommended in order to avoid unnecessary exposure to Hg [mercury].”(8)
For more information: Pregnancy, Children, & Dental Amalgam Mercury Fillings.
3) Dentists and Dental Personnel:
Researchers have also demonstrated dangers to dental personnel who routinely work with amalgam, and the Norwegian Labour and Welfare Service has officially recognized mercury injury as an occupational disease. 4) Safe Removal of Existing Amalgam Fillings: Whereas “mercury-free” dentists no longer place amalgam fillings and use available alternatives, “mercury-safe” dentists apply special techniques to remove existing amalgam fillings. In fact, the IAOMT has developed rigorous recommendations for removing existing dental mercury amalgam fillings to assist in mitigating the potential negative outcomes of mercury exposure to patients, dental professionals, dental students, office staff, and others.(9)
How Do We Remove Mercury Fillings Once They are in Place?
Safe Mercury Amalgam Removal Technique (SMART)
The SMART technique was developed by the International Academy of Oral Medicine and Toxicology (IAOMT). The IAOMT is a trusted academy of allied professionals providing scientific resources to support new levels of integrity and safety in healthcare. SMART is a set of recommendations created by the IAOMT based on scientific research that includes pre-operative procedures to prepare body for removal of amalgam fillings, maximum protection protocols for patient, dental team, and environment, ventilation, biocompatible replacement materials, among other measures.
1 World Health Organization. Mercury in Health Care [policy paper]. August 2005: 1.
3 Heintze SD, Rousson V. Clinical effectiveness of direct Class II restorations—a meta-analysis. J Adhes Dent. 2012; 14(5):407-431.
4 Makhija SK, Gordan VV, Gilbert GH, Litaker MS, Rindal DB, Pihlstrom DJ, Gvist V. Dental practice-based research network restorative material: Findings from the characteristics associated with type of practitioner, patient and carious lesion. J Am Dent Assoc. 2011; 142: 622-632.
5 Many scientific studies support this, but an example from a reputable government agency is Health Canada. The Safety of Dental Amalgam. 1996: 4. 6 Scientific studies support this fact, but one example of this being reported from a reputable U.S. environmental group is State of Connecticut Department of Environmental Protection. Fillings: the choices you have: mercury amalgam and other filling materials [brochure]. 2006: 3.
7 Health Canada. The Safety of Dental Amalgam. 1996: 4.
8 Al-Saleh I, Al-Sedairi A. Mercury (Hg) burden in children: The impact of dental amalgam. Sci Total Environ. 2011; 409(16):3003-3015.
9 IAOMT. Safe Removal of Amalgam Fillings. Available from: