Mercury in Dental Amalgams: Possible Risks and Regulation

We recently received an ‘Ask the Expert’ question dealing with mercury filling particles in water. Our reader asked, “A dentist drills out a tooth that was previously restored using mercury dental amalgam filling – It’s estimated that 135 mg of mercury by weight enters into an 3.4L of H20 batch solution during this process: How do I calculate the amount of mercury particles in that 3.4L of Water?”

To answer this question, we’ll discuss the following underlying questions:

  • What’s a mercury dental amalgam?
  • What are the risks associated with mercury when it is used as a dental amalgam?
  • What are the legislated limits on mercury in the water supply in the United States?
  • How do we measure the concentration of a solution? (We will consider the units ppm, mg/l and number of particles in the solution.)

Mercury is a metal liquid at room temperature. Photo by Ignacio Conejo

Mercury Fillings: Dental Amalgam

Mercury fillings, or dental amalgams are materials used by dentists to fill possible cavities present in teeth. Their composition can vary, but generally, mercury (Hg) is the main component – about 50 % weight. The other elements present are silver (Ag), tin (Sn) and copper (Cu).

The amalgam is formed due to the reaction of mercury with the other metals. Hg, being liquid, dissolves into the other solid elements, and chemical bonds form between Hg and the metals.

Mercury Toxicity

Mercury is a metal widely used for technological applications, due to its peculiar properties. It is the only metal which is liquid at room temperature; this makes it suitable, for instance, for use in thermometers.

Mercury, however, is also a very toxic element; for this reason, in some applications Hg has been replaced by less toxic elements/compounds. When Hg is employed, stringent legislation is in place to regulate its use, the disposal of Hg-containing wastes and its maximum concentration in the environment.

Considering US legislation, the Environmental Protection Agency (EPA) established a series of limits for Hg concentration values. These apply to water and air concentrations, but also to the maximum amounts which may be emitted from different sources (i.e. industrial processes, combustion of wastes, etc.).

The EPA water concentration limit of mercury is 0.2 ppm.

Click to Read Page Two: Risks of Mercury Fillings

© Copyright 2012 Clara Piccirillo, PhD, All rights Reserved. Written For: Decoded Science
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  1. Michael Dungelman says

    I am truly curious as to when the people in charge of protecting the people they represent will stop accepting pro-amalgam contributions to campaigns and stand up for what is right. I am 31, and only five weeks ago it was brought to my attention that the ten mercury amalgams in my mouth have been gradually poisoning my body since the moment they were set. I may need to take out a loan to properly remove the amalgams, but my life is most certainly worth it! Someday my mouth won’t taste like metal, and I hope it is very soon. Since my current dentist believes that mercury amalgams are ‘safe until proven harmful’ I will need to find a dentist in New Hampshire or within a two hour drive that I can trust to remove this poison.

  2. Paul says

    They are not interested Freya what you say is exactly right the people who are behind amalgam fillings want a slow retraction of these fillings so they can continue to financially benefit from their placement. This is an example of capitalism at its worst maybe the communists were right capitalism can have very evil undertones. But the corporations need to understand it is the people who hold the true power and if everyone boycotts these fillings as they should after all who wants something that toxic that has never been prooven scientifically to be safe, but has been shown to leak mercury vapours in their mouth !!!! The indifference these pricks show to an individuals right to live a healthy life makes me hostile, not angry not annoyed not irritated hostile!!!!!! an in the words of Rage Against The Machine an a song that is totally appropriate to this situation I say We Gotta Take The Power Back!!!!!

  3. says

    Dear Clara,

    re: Mercury in Dental Amalgams, Possible Risks and Regulations

    As a scientist, you note that you are aware that mercury is an extremely toxic element. In fact, you mention that in some applications Hg has been replaced by less toxic elements. You are correct, however, you don’t mention that one of those applications is silver amalgam dental fillings containing 50% mercury, a known neurotoxin. Half of U.S. dentists no longer use silver mercury amalgam fillings because of its extreme toxic nature to health and the environment. A large percentage of UK dentists also have chosen not to use fillings containing mercury….they are using white non-mercury composite fillings.

    I refer you to the website of the International Academy of Oral Medicine and Toxicology, a scientif dental organization that has been researching the dangers of mercury fillings for more than 30 years. Search for the scientific references contained in their “Petition for Reconsideration” filed by the IAOMT with the U.S. Food and Drug Administration. There are references to the levels of mercury exposure from these fillings and the various diseaases associated wiht mercury fillings, such as MS, Lupus Parkinson’s, ALS and Alzheimer’s Disease.

    There are also references related to the dangers of prenatal exposure from maternal dental fillings.

    Not only is the patient at risk, but dental personnel as well. Note: mercury exposure in female dental personnnel has shown a very high rate of infertility, miscarraige and cancer. Also, the Hg in the maternal amalgam fillings of pregnantn women is transferred to the developing fetus, and thus can damage the developing nervous system. This type of exposure has been linked as a contributing factor to autism .

    I am an injured consumer. r one was struck with double vision 14 years ago and diagnosed with Multiple Sclerosis, Lupus and Myasthenia Gravis Mercury is known to effect the immune system, and therefore can cause autoimmune diseases.

    As a scientist, I highly encourage diligent reliable research on your part rather than referencing articles from the Journal of the American Dental Assoc. a trade organization with financial stakes in keeping amalgam fillings alive. In fact, the ADA would prefer that dental amalgam take a slow quiet death. The ADA does not want to be held accountable for the millions of people who have suffered and died of amalgam mercury poisoning. They preach “preventive dentistry” rather than the mandatory removal of mercury filling from use.

    Unfortunately for the public, the ADA has suppressed the risks of mercury fillings for more than 100 years. From a logical and scientific point of view, mercury fillings should be banned fro use immediately as was done in Sweden, Denmark and Norway.

    There is no sane reason for promoting or endorsing its use for any segment of the population.

    I hope that you will reconsider your comment and write a follow up article with appropriate recommendatons to the public.

    Thank you,
    Freya Koss
    Director, Pennsylvania Coalition for Mercury-Free Dentistry

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