If have read conflicting reports on the half-life of mercury in the brain. I would like to hear some estimates from this community. I am also wondering how long chelation therapy would take to remove mercury from the brain.

  • $\begingroup$ I don't think chelation therapy will remove mercury from the brain. Chelators are good at grabbing inorganic mercury, but the brain usually takes up organic mercury. Chelation therapy for mercury poisoning tends to be reserved for acute mercury exposure, not chronic exposure, as the chelators often have side effects. Why are you concerned with mercury in your brain? $\endgroup$
    – user137
    Aug 16, 2014 at 23:58
  • $\begingroup$ I have amalgam fillings and I am concerned that the mercury vapour they release - 80% of which is taken up by the lungs - has crossed into my brain and is causing mild symptoms such as concentration problems. $\endgroup$
    – user123082
    Aug 19, 2014 at 14:25

3 Answers 3


Since you're concerned about mercury from fillings, you may have already taken a look at the wikipedia article about dental amalgam toxicity. It would be worth reading through some of the sources listed, too.

I assume you're an adult, I don't know if you're male or female. Children are more sensitive to mercury than adults because their brains are actively developing. If you're female, you may become pregnant at some point and there would be some concern about fetal mercury exposure.

However, according to a 2003 WHO report, the amount of mercury ingested from dental amalgam is low, with exposures estimated from 1ug per day to 12.5ug per day, but the vast majority of people are exposed to less than 5ug per day. The mercury from fillings is elemental mercury, which is poorly absorbed, less than 0.01% is taken up, with smaller amounts reaching the brain.

Removing your existing fillings probably isn't worth it, as the removal process would expose you to more mercury than just letting the filling sit there.

I don't know if this will make you feel better or worse, but coal fired power plants are probably a larger source of mercury exposure than your fillings. The mercury from the coal plants is methylmercury, which is much more efficiently absorbed than elemental mercury. This bioaccumulates in the environment, so that fish have relatively high levels of mercury in them.

As far as your perceived concentration problems, we really can't say if it's caused by the mercury or not. If it concerns you, you should see a doctor. And it may be more efficient to treat the symptoms through ADD medication than trying to remove mercury.


I have read reports of amalgam fillings producing as much as 50 µg per day of vapor with a 80% uptake through the lungs. This is what worries me. There is evidence that the half-life of mercury in the brain is many years.

  • $\begingroup$ It would be better if you put this as comment $\endgroup$
    – Freddy
    Aug 20, 2014 at 4:58
  • 1
    $\begingroup$ This is fine as an answer as long as you summarize the evidence that's in the paper. This question overall is a bit borderline for our scope, though, since it's more of a health issue than something that we can answer from a chemical safety perspective. $\endgroup$
    – jonsca
    Aug 20, 2014 at 7:24
  • $\begingroup$ If there is no information on the chelation aspect in the publication, this is probably best left as a comment as several users have indicated. $\endgroup$
    – jonsca
    Aug 20, 2014 at 7:25

The study below (2014) suggest the half life in the brain (where it counts for mercury poisoning), may be much longer than thought: on the order of years or decades.

The retention time of inorganic mercury in the brain--a systematic review of the evidence. (https://www.ncbi.nlm.nih.gov/pubmed/24368178)

Also: article about this study (http://www.speciation.net/News/A-new--study-finds-Inorganic-mercury-stays-in-the-brain-for-years-if-not-decades-;~/2013/12/29/7042.html).

  • $\begingroup$ Welcome to Chemistry! Take the tour to get familiar with this site. Links and other bits of text can be formatted using Markdown. $\endgroup$ Jun 24, 2017 at 17:49

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.