Chelation: Getting the lead out

Lead-based paint (was banned in the U.S. in 1978) and old water pipes are the most common causes of lead poisoning. It still shows up in contaminated water, air, or soil.

The good news is that lead poisoning is largely treatable, and the earlier it is detected the better. Let’s look closer at treatment methods…

Diagnosis, first

If you are suspecting lead toxicity as the cause of symptoms, have your doctor order a blood test to measure it. For example, the lab I use most is Labcorp. They have a whole blood lead level test or even better, the Heavy Metals Profile I. There is also a finger stick test.

Remember that there is no safe blood level of lead. It’s been tied to illnesses ranging from mystery military ailments to heart disease.

The most important first step to treating lead poisoning is to identify and remove the source of the contamination the best you can. For the majority of us, know that lead-based paints were routinely used in homes build before 1978 and that even household dust is a major source of lead.

Treatment for lead poisoning

Chelation is a method of binding up metal molecules so it can be eliminated via the urine. There are also antioxidants (e.g. N-acetylcysteine) that help to remove lead from the body which I’ll address below.

The first and safest chelation method is by taking a pill called DMSA (meso-2,3-dimercaptosuccinic acid) or DMPS (2,3-dimercapto-propanesulphonate). These are pills and have low side effects or toxicity. DMSA is less toxic than DMPS. It takes several months of taking these weekly or twice weekly to slowly release lead from tissues.

Ethylenediaminetetraacetic acid (EDTA) was first patented in 1938 as a chelating agent capable of binding metallic and non-metallic ions and releasing them from physiological tissue.¹ Therefore, calcium disodium EDTA chelation is approved by the FDA for use in treating not only lead poisoning but also other heavy metals. It removes heavy metals and minerals from your blood such as lead, iron, copper, and calcium.

Calcium disodium ethylenediaminetetraacetic acid (EDTA) is given by IV injection, but oral pills are available, though they would work much more slowly.

The EDTA-metal chelate Edetate disodium (the sodium salt of EDTA) binds to calcium and first used to treat hypercalcemia and digitalis intoxication before it became popular in reducing atherosclerosis and cardiovascular disease.

Once in your bloodstream, calcium disodium EDTA sheds its calcium bond and aggressively chelates toxic heavy metals such as lead and mercury, whichever metal molecule it comes in contact with first.

Calcium disodium is not very well absorbed from the gastrointestinal (GI) tract; only about 5-18% actually makes it into your bloodstream where it can chelate and remove toxins. Additionally, unabsorbed calcium disodium EDTA (the portion that does not get back into the bloodstream) continues to chelate toxic metals as it passes through your intestinal tract.

The GI chelating effect of oral chelation of other metals was demonstrated at the University of Michigan in a small study. They measured the excretion of unwanted heavy metals 14 patients after taking one dose of oral calcium disodium EDTA. It showed dramatic excretion of unwanted heavy metals by the following amounts: aluminum: 229%; Arsenic: 661%; Cadmium: 276%; Lead: 350%; Mercury: 773%; and Nickel: 9439%.

You should know that with oral chelation you may lose some beneficial trace elements such as zinc and calcium along with the toxic ones listed above.  However, with a diet of adequate fresh vegetables — or even supplementing with zinc and calcium, you can easily overcome this. Yet, some good news here is that EDTA appears not to deplete the trace minerals cobalt, chromium, and copper and even helps retain the beneficial trace mineral magnesium.  Furthermore, EDTA is an amino acid that enhances the absorption of zinc with protein and the amino acids cysteine and methionine.

Although the topic of another article, EDTA has been proven in many prior studies to reduce cardiovascular disease especially.  The more recently completed TACT trial by the NIH proved the tremendous benefit of EDTA for diabetics.  What’s more, EDTA and supplemental chromium have both been shown to improve blood glucose, lipids, and insulin activity in diabetic patients. This was demonstrated and reported in the December 1999 issue of Biological Trace Element Research.

The other chelators for lead

These two chelating agents (DMSA and EDTA) have been studied and compared. Here is what research has shown us about them:

• Sodium calcium edetate causes dose-related nephrotoxicity.
• Both agents (DMSA and EDTA) deplete zinc and copper. The effect on zinc is significantly greater with EDTA.
• A transient increase in liver function (transaminases) is more common with DMSA, but neither causes any clinically significant liver toxicity.
• Skin lesions during treatment with EDTA are unusual and have been attributed to zinc deficiency.
• DMSA has occasionally been associated with a severe mucocutaneous reaction necessitating discontinuation of therapy.
• DMSA pills and EDTA infusions are both effective chelators of lead and considered equally effective. Both antidotes resolve symptoms of moderate to severe lead toxicity fairly rapidly.

Chelator antioxidants

Chelator antioxidants have the ability to decrease blood lead levels and the oxidative stress that results from lead poisoning. Glutathione and N-acetylcysteine are two of these that have shown effectiveness. N-Acetylcysteine is a natural antioxidant. It is a precursor to cysteine and glutathione in metabolic pathways. Both are detoxifying agents for heavy metal ions.

However, as far as I understand them, they are proving their effectiveness in animal studies but used in mainstream medical practice due to the lack of human studies.

To long-term health and feeling well,

Michael Cutler, M.D.

Sources:

1. Lead, Whole Blood (Adult) — LabCorp
2. Heavy Metals Profile I, Whole Blood — LabCorp
3. Lead, Blood, Filter Paper — LabCorp
4. What can I do to protect my family from lead contamination that was found in my neighborhood? — Pollution Prevention and Toxics | U.S. EPA
5. Chen W, Ercal N, Huynh T, Volkov A, Chusuei CC. Characterizing N-acetylcysteine (NAC) and N-acetylcysteine amide (NACA) binding for lead poisoning treatment — J Colloid Interface Sci. 2012 Apr 1;371(1):144-9. PubMed PMID: 22284448
6. Bjørklund G, Mutter J, Aaseth J. Metal chelators and neurotoxicity: lead, mercury, and arsenic — Arch Toxicol. 2017 Dec;91(12):3787-3797. Review. PubMed PMID: 29063135
7. Waters RS, Bryden NA, Patterson KY, Veillon C, Anderson RA.  EDTA chelation effects on urinary losses of cadmium, calcium, chromium, cobalt, copper, lead, magnesium, and zinc — Biol Trace Elem Res. 2001 Dec;83(3):207-21
8. Mohamedshah F. Mineral absorption: zinc, selenium, chromium, calcium — Slide presentation at National Institute of Health Bioavailability Conference; January 5, 2000.
9. Chelation for Coronary Heart Disease — National Center for Complementary and Integrative Health (NCCIH)
10. Anderson RA, Bryden NA, Waters RS. EDTA chelation therapy does not selectively increase chromium losses — Biol Trace Elem Res. 1999 Dec;70(3):265-72.
11. Bradberry S, Vale A. A comparison of sodium calcium edetate (edetate calcium disodium) and succimer (DMSA) in the treatment of inorganic lead poisoning — Clin Toxicol (Phila). 2009 Nov;47(9):841-58. Review. PubMed PMID: 19852620
12. Gurer H, Ercal N. Can antioxidants be beneficial in the treatment of lead poisoning? — Free Radic Biol Med. 2000 Nov 15;29(10):927-45. Review. PubMed PMID: 11084283
13. Sisombath NS, Jalilehvand F. Similarities between N-Acetylcysteine and Glutathione in Binding to Lead(II) Ions — Chem Res Toxicol. 2015 Dec 21;28(12):2313-24. PubMed PMID: 26624959
14. Chen W, Ercal N, Huynh T, Volkov A, Chusuei CC. Characterizing N-acetylcysteine (NAC) and N-acetylcysteine amide (NACA) binding for lead poisoning treatment — J Colloid Interface Sci. 2012 Apr 1;371(1):144-9. PubMed PMID: 22284448