Mercury Toxicity
and Mercury Poisoning

Mercury toxicity and mercury poisoning are closely related, because they are both caused by mercury. BUT they are NOT the same thing.

MERCURY TOXICITY refers to the toxic effects that the various forms of mercury MAY have in humans. BUT toxicity IS NOT THE SAME as poisoning! They are two separate things, although they are related.

MERCURY POISONING refers specifically to the symptoms of poisoning, not toxicity. Just because you eat a lot of fish with mercury in it doesn't mean you will necessarily get mercury poisoning - But you may get some symptoms of toxicity.

Let me explain a little further.

Mercury Toxicity

ALL mercury compounds are toxic to some degree or another. But you only get mercury poisoning if you ABSORB ENOUGH MERCURY. This will vary from person to person, depending on the form of the mercury compound, your mercury exposure, and your genetic make-up. The different forms of mercury are absorbed in different ways and so to different degrees.

Some forms of mercury are MUCH MORE quickly absorbed than others.

Mercury poisoning can result from:

  • Breathing in mercury vapor.
  • Swallowing mercury.
  • Or absorbing it through the skin.
Liquid Mercury dropsLiquid Mercury

From a dental point of view, most people think that you might absorb mercury by swallowing the small amounts that come off your fillings. In fact, any mercury coming off amalgam fillings is nearly all in the form of mercury vapor.

Breathing mercury vapor will result in about 80% of the vapor being absorbed by your lungs, and then going into your bloodstream.

It gets into your bloodstream quickly because the mercury vapor is "fat-soluble", and dissolves easily in body tissues. In the bloodstream it is mostly converted into an insoluble form by the red blood cells.

HOWEVER, small amounts of soluble mercury remain, and this soluble mercury is responsible for mercury toxicity to your central nervous system. Because it is SOLUBLE it can get into most tissues in the body, but seems to be absorbed most strongly by the central nervous system.

Mercury Toxicity

In trying to reduce the exposure to mercury, one option a lot of people think about is amalgam filling replacement. Done correctly, this can eliminate any mercury vapor that may be coming off amalgam fillings.

Before and after photos of three amalgam fillings being replaced with tooth-colored composite fillingsAmalgam filling replacement

Where there are clear symptoms of mercury poisoning, and this has been medically diagnosed, a further possibility is mercury chelation therapy. But you should only think about this AFTER eliminating the SOURCES of mercury. You HAVE TO ELIMINATE the sources of mercury getting into your body BEFORE you start trying to deal with any accumulation of mercury or other heavy metals.

WHAT ARE THE OTHER sources of mercury in your life?

The MAIN sources of mercury are likely to be:

  • From your environment; either exposure at your place of work due to industrial use of mercury, OR exposure by accident, through contact with mercury-containing devices or substances.
  • From your food, in particular certain types of fish.
  • From domestic items such as cosmetics, paints and fungicides.
  • Dental amalgam fillings.

So, if you are having health problems that your doctor has identified as being consistent with mercury poisoning, the first thing to do is look at where the mercury came from!

Do you work in an industry that has anything to do with mercury in it's processes?


have you been in an office where a number of mercury-containing "compact fluorescent light" bulbs have broken?

Do you eat a lot of fish? Could any other types of food you eat have been contaminated, for example sprayed with mercury-containing fungicides?

You need to go through this process slowly and carefully. Don't assume anything. You need to eliminate all potential sources of mercury in your life.

There are many industrial sources of mercury. For example, mercury can be released during the extraction of gold during some gold mining processes.

Mercury vapor may be released during the industrial manufacture of chlorine.

Quite a few items of electrical equipment can contain small amounts of mercury, such as low-energy light bulbs and some batteries. Surprisingly, mercury compounds can also be found in a number of medicines and skin products!

Mercury can be found in fungicides and paints. In the vicinity of hazardous waste dumps, it can be detected in the air and soil.

That's a lot of places you can get mercury from!

The Food and Drug Administration (FDA) in the United States has estimated that, on average, most people are exposed to about 3.5 micrograms of mercury per day. A large proportion of this mercury is likely to come from fish. The safe exposure limit is over 10 times that figure, at 50 micrograms per day.

However, some people will be more sensitive to mercury than others, and it is possible that symptoms of mercury toxicity can appear at levels well below 50 micrograms per day.

While there are many ways of testing for mercury poisoning, the only reliable and consistent method is urine testing. ALL OTHER methods are unreliable for one reason or another.

While mercury toxicity is a very real danger, true mercury poisoning is quite rare, and any mercury vapor coming off dental amalgam fillings is likely to be only a part of the problem.

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  1. Dental Advice
  2. What Is An Amalgam Filling?
  3. Mercury Toxicity