Chelating Safety

Mercury poisoning from dental amalgam is a controversial issue. The economic interests of the dental industry are pitted against the good health of many millions of people worldwide. Both the long enjoyed wealth generation and now potential liability of those who supply and install mercury dental fillings make this a difficult issue for dentists to address with intellectual honesty. The economics pit those who suffer from amalgam-mercury poisoning against those who profit from mercury use as an inexpensive, easy to install dental restoration material.

Sadly, once you finally conclude that mercury from dental amalgams is indeed causing your illness you enter into new topics of controversy and uncertainty. Chelation treatment is such a topic. If mercury accumulation in the body is the ultimate cause of illness then it is only logical that removing at least the disruptive portion of the body's burden of mercury seems essential. If on the other hand the treatment is known in some cases to cause more damage, or lead to a long term worsening of problems -- one has to beware, fully informed, and take steps to mitigate risk before fully embarking on such a treatment.

The term "chelation" is used in the context of this article to generally mean chemical binding and excretion of mercury by any mercury complexing compound. Chelation can be accomplished with nutrients and/or drugs. In normal health the body uses its enormous glutathione stores to detoxify and remove mercury from the body. NAC (N-acetyl L-cystiene) is a widely available glutathione precursor that has the ability to directly bind and excrete mercury via its single thiol (sulfur atom) as well as support and increase the body's store of glutathione as a precursor. The nutrient ALA (alpha lipoic acid) is a dithiol (with 2 sulfur atoms) compound that is normally used by the body in small amounts as part of the enzymes for producing cellular energy. Because of its two sulfurs, ALA can bind and transport mercury for excretion from the body. The two drugs most commonly used as mercury chelating agents are DMPS (2,3-dimercapto-1-propane-sulphonic acid) and DMSA (DL-2,3-dimercapto-succinic acid, both are man made dithiol chemicals. Another compound used as an industrially chelator is EDTA (Ethylenediaminetetraacetic acid). Yet another compound commonly used as an alkalyzing agent is potassium citrate, which also appears able to directly chelate mercury atoms.

Safety of Chelators

There are several factors that influence the safety of a chelating substance. Is a person able to metabolize and excrete the drug with and without mercury attached ? What additional , potentially adverse effects does the chelating agent have on other minerals and nutrients ? Will the chelating agent cause the redistribution of mercury in an unhealthy way ? Finally, does the chelator have the potential to cause damage as it extracts mercury from your tissues ? or is it possible for a chelator to be too good at attracting mercury ?

For many reasons the kidney is a key point of heavy metal accumulation within the body and an important site of mercury toxicity. The kidney is a mechanical and chemical filtration system that completely filters all extracellular water of the body 16 times a day. Each beat of the heart sends blood first to the kidneys with the highest pressure to be found anywhere in the circulatory system.

Water and water soluble contents from plasma are seperated from blood cells and are forced into a kidney tubule by glomerular filtration. The kidneys have many thousands of these thousands of these tubules. Each kidney tubule is a very small capillary sized tube shaped like a hair pin with a proximal end first half of the tubule) and a distal end (second half) which drains into ever larger branching tubes within the kidney that finally consolidate into the ureter that drains into the bladder which stores urine for controlled excretion.

The kidney proximal tubule is the main point of interest regarding mercury accumulation, toxicity and excretion. Each tubule also has an inside (lumen) and an outside (basolateral). The lumenal side of the kidney tubule cell is a villiated membrane called the "brush border". The villiated lumenal cells of the

Glutathione should always be the first chelating agent to consider as it is the body's natural chelating agent. Indeed, it is beleived that a breakdown in the body's glutathione stores, synthesis and reclamation are a prerequisite to developing mercury toxicity. Glutathione (GSH) in the blood directly binds inorganic mercury (Hg2+) in a 2:1 ratio of GSH-Hg-GSH. This complex is seperated from the blood cells along with the rest of the water soluble contents of plasma at the kidney via glomerular filtration.

Dose Rate

Fat soluble chelators excrete mercury through the liver. There is a bile loop. Liver excretions dump into the beginning of the small intestine as bile. Mercury bearing proteins will be broken up by digestive and microorganism actions in the small and large intestines.

Freed methyl mercury rapidly reabsorbs back into the human. If you take a large dose of chelator, you will excrete a large dose of mercury into the bile. You will then receive a large dose back in through the GI.

Such a large scale activity will redistribute mercury, which can be quite bad. Small daily accumulations over a long time gives your body opportunity to direct storage of the poison it can't excrete. As much as possible is placed in less disruptive places. A large dose has high potential to be much more disruptive, with little body influence over storage location.

Taking NAC (N-acetyl L-cysteine) and the other GSH (glutathione) precursors allows your body recourse on the bile loop.

It is believed that the bile loop is not 100% efficient, meaning some of the mercury bearing protein always flows out with feces. The reabsorbed methyl mercury will go out the liver again and again until carried in feces all the way out.

You need to have enough GSH and NAC to constantly confront the reabsorbed mercury. The perils of this bile loop also speak to the benefits of occasional whole bowel cleansing.

Water soluble chelators such as DMPS and DMSA excrete mercury through the kidneys. A dose overload from either of these man made chelators can damage your kidneys.

Get into the amino acids right away, regardless what you may eventually decide about the synthetic chelators.


A controversial chelator. There are two sides to this molecule. My success is the good one. My friend Hg is truly the other extreme.

My story is well documented elsewhere in this web site, so I will not repeat it all here. I will reiterate that I saw noticeable improvement from before the DMPS treatment by three weeks after each time. I may have just been lucky.

I know that I didn't ever develop porphyria, and I don't have sulfa intolerance. I have also been controlling yeast from time immemorial, have had a nutritious diet, and have used saunas for years. My doctor started me out on half doses of DMPS for the first 4 chelations.

Hg on the other hand, has only been dosed twice with DMPS. His first time it was the currently accepted full 250 mg dose. It almost killed him. He has the pictures to prove it. He tells me his kidneys, pancreas, liver and immune system were damaged by his intolerance and resulting mercury redistribution.

After he recovered, Hg tried again with a one fifth dose. This second time his face became severely swollen. Since his encounter with DMPS, Hg's mercury toxic effects have been far worse, and more widespread than before the mistreatment.

Only by pluck, and hard learning has he been able to return from the dead. Hg was so anorexic that people thought he was in late stage AIDS. Happily, I can report that he has made significant recovery since then.

My personal interpretation of Hg's experiences is that he had both a possible overdose of DMPS relative to his very high mercury levels, and another reaction too. Hg's experience caused a harmful redistribution of mercury, and subsequent organ damage.

Hg now personally knows 6 people who have had similar very bad experiences with DMPS. He is adamant that people shouldn't be using this drug without careful pretesting for intolerance.

For intolerance testing Hg recommends that small oral doses, of not more than 100 mg be taken with a 14 day waiting period for side effects.

Side effects to be watching for are lower back - kidney pain; indigestion, and skin rashes. Hg also feels that IV administered DMPS is unnecessary and additionally risky. Overall, he feels oral DMSA is a safer chelation route.

My conclusion is that you and your physician need to be very careful with this substance. If you have sulfa intolerance, porphyria symptoms, or a history of allergic reactions to different materials, you should steer clear. If you don't see a cause to refrain from DMPS, you should get tested with the small dose first, to be sure you are not going to react in a bad way.

The contrast between my story and Hg's is proof enough for me that the outcome of using this substance is volatile. If you take it and don't see signs of improvement, but only signs of worsening, then something is not right, and you shouldn't take it again.

I know DMPS to be disruptive, making you feel much worse first. Better comes later on it's own after you recover from the treatment.

In my case improvement always came within a few weeks. The nutritional protocol spelled out elsewhere in this web site is going to help you no matter what else you choose to do. There is prudence in pursuing nutrition first.

Follow the DMSA approach below if you see enough concern to be risk averse but still want the mercury out ASAP.

You have to decide for yourself, DMPS is a gamble. Hg, who's pages are linked in this web site, plans to explain why he believes DMPS is bad for people in greater detail.


This chelator is not a sulfa based drug. The molecule is based instead on succinic acid, not the propane used in DMPS. DMSA is FDA approved, unlike DMPS, and is only taken orally.

I've read reports that demonstrate equal effectiveness with DMPS at protecting against mercury toxicity in lab experiments. DMSA has been shown more effective at removing organic mercury than DMPS. As reported elsewhere on this web site, released dental mercury is believed to be converted to methyl mercury within the human ecosystem.

Hg takes this one, and contends it is safer than DMPS. Hg allows that no chelator is 100% safe. Hg feels that all man made chelators are risky including DMSA. He has at least one contact that has had bad side effects from DMSA, though not as bad as the side effects from the DMPS backfire cases.

Once again, the nutritional approach would seem to be the safest remedy.


Dr. Haley, a Ph. D., has shown that EDTA can cause a 100X toxicity increase with mercury in the brain. Severe damage to the brain tubulins can occur, resulting in Alzheimers like dementia. Need we discuss this further ?

BAL and D-penicillamine

Both are shown in the clinical experiences to be less effective at removing mercury than DMPS, DMSA, and NAC. BAL has a high rate of mercury redistribution and side effects. D-penicillamine causes auto immunities in long term use by arthritis patients.


Both of these are aimed at natural chelator defenses. NAC (N-acetyl L-cysteine), which is described in better detail on the nutrition page of this web site, is an amino acid that is an effective precursor of GSH. NAC is also a liver friendly mercury binder and excretion vehicle.

GSH (glutathione) is what your body creates from NAC and two other amino acids, but is difficult to absorb intact from the GI as a food supplement. Injected GSH has difficulty passing inside individual cell walls.

NAC can have non-damaging chelation side effects if taken in large doses. Self made GSH is without known side effects.


Be careful not to make matters worse! Monitor your own condition patiently, don't continue doing anything that shows only negative or life threatening side effects. Effective safe chelation should make you feel better within weeks. You can expect to recover only after well spaced treatments and many months.

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Copyright ©1996 / 1997 Jeff Clark