[twkp114]

First of all, "hi!"
I'm new here and relatively a noob in chemistry.
Please forgive me if this is a misplaced thread.

Please don't flame me for this, but it is a
question that relates to Mercury (Hg) and
amalgam fillings. Yikes!

I have tried to research this subject.
Yet, I seem to find a definite divide;
with insufficient answers.

So,

-A dentist's response was that the Hg, when
mixed with the additional materials, was
"locked-in".

-I don't believe it is a safe substance. If a dentist
is willing to say such a thing, then I would like to have
an understanding of how that actually works.

-Needless to say, it didn't put my mind at ease to
hear "locked-in" with zero attempt to define it.

-I swear I'm not trying to be an alarmist here.
I'm just trying to find and understand the facts.

So is that accurate? From what I've read I tend to
doubt it. I am not a chemist though.

Please forgive my ignorance of the subject, but wouldn't
the Hg be somewhat exposed, at least at the surface of
the amalgam?

What about substances that react with the amalgam (like
acidic foods, hot beverages, bio-substances)?

What about environmental factors, such as body temp.,
abrasion from chewing (as well as pressure), direct contact
with bio-tissues, etc.?

Yes, I will admit I have a fear of the substance. Also,
I already disbelieve the safety of it. So feel free to
be honest in the facts. I sincerely would like to learn
and understand the interactions of this spooky
substance.

Please explain in detail the interactions of Mercury.
(I apologize in advance if this subject upsets anyone,
or if it is in the wrong forum.)

*Thank you

[OC pro]

Of course tiny amounts of Hg get into your body over the time but this is nothing you should worry about.

[Borek]

"Locked" is not the best word to use in this context. However, mercury is very difficult to leach from the amalgam and its vapor pressure over the amalgam is also extremely low, which made the amalgam quite safe selection.

This is one of these cases were adverse effects - if they exist - are so low, they are very difficult to distill from the background noise. Whenever it is obvious that the adverse effects exist, we get unambiguous results and quite fast it is obvious that the problem exists. The longer the controversy, the longer the research without a conclusive result, the more obvious it becomes that we are hunting ghosts, not real problems.

[twkp114]

Hey,

Thank you for your replies!
I really do appreciate hearing
from people with a chemistry-
background.

May I ask, what about substances
that interact with the amalgam/mercury?

Like, what if someone used a
chelating agent?

[fledarmus]

You might be interested in reading this post. It tries to correct some of the alarmist discussion about the putative effects of incredibly low exposures to mercury from fillings.

http://www.sciencebasedmedicine.org/index.php/mercury-must-be-bad-if-not-in-vaccines-in-teeth/#more-138

[vmelkon]

That sciencebasedmedicine site links to a YouTube video that I had seen before but I didn't think much of it. Now that I think about it, that is a lot of vapor coming off it. I have a hard time imagining that a tooth would emit that much hg on a continuous basis. I have seen another video of an amateur doing that kind of imagery, except he used pure hg.

Hmm, somebody is lying to me.

[Jasim]

Another thing to consider, and something few people seem to be aware of, is that only some types of mercury are dangerous. You mentioned that you don't have much background in chemistry so I'll try to briefly explain what I mean by different types as I'm sure that may be a question.

Metals have different oxidation states, meaning they take on different charges. It's still the same metal, but the chemistry acts different. they have more or less electrons. A perfect example of how this can affect toxicity is by looking at chromium. The Erin Brockovich case involving hexavalent (Cr in oxidation state of 6+) highlighted in the public eye how toxic the substance is. But chromium is also considered an essential mineral and is put in muiltivitamins. The difference bewteen the two is that chromium can take a variety of oxidation states, Cr +3 for instance is not toxic.

In the case of mercury, the most toxic form is mercury 2+, though mercury 1+ is still toxic. Elemental mercury (oxidation state of zero) is the type of mercury used in dental amalgam. Elemental mercury is very poorly absorbed into the body, even when ingested. The absorption of mercury plays a critical role in it's toxicity. Methyl mercury for instance is very rapidly absorbed and hence is extremely toxic, one of mercury's most toxic forms in fact.

Dental amalgam has been controversial since it was first created in the late 1800s. All empirical and medical evidence that I have seen suggests that it is safe for use. Keep in mind that mercury was once common in grade-schools, children played with it with bare hands. In general mercury is not as toxic as many believe, it is only specific types of mercury that are toxic.

[twkp114]

Thank you all for your friendly replies!
Interesting stuff.

Nice article-find. I've read a few things related to
the sheep studies. The "60 Minutes" segment
seems rather notorious from what I've read.
I suspect there are a lot of subjects that
find their way into the news via such
mediums.

Actually, an aunt of mine was telling me about
a time when she herself played with mercury
in school. I didn't really know what to make
of that, though.

Thank you for anticipating that question; it's
precisely the kind of information I'd like to
know about.

I am not familiar with the different types of
mercury. I vaguely remember something
about the +electrons (it's been a long time).
I never knew the significance of the +'s
as they relate to toxicity. That's interesting.

Again, thank you all so much for the useful
feedback. I do appreciate it...
I'll sleep better with that information.

*(Does anyone know the process of chelation,
in relation to toxicity? Like, does a chelating-
agent interact differently depending upon the
different +type of an element?)

[Jasim]

chelating agents kind of 'grab' onto the specific compound(s) they are made to chelate. This grabbing allows the chemicals to be removed, it also sequesters them - meaning they are now less likely to react or be absorbed.

You are on the right track with regards to chelation of different types of ions. As I understand it you can actually use specific chelating agents to remove elemental mercury from mercury 1+.

[twkp114]

Much thanks, Jasim!

I'm trying to learn more about that.
I'm curious about reabsorbtion, and
redistribution of the chelated particles.

That kinda gives me a starting point
to hunt for. Thank you.