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Chelation & Lead Toxicity

An overview of lead exposure, blood testing, prevention and the limited circumstances in which chelation may be considered by qualified clinicians.

Dr. Colin MacLeod, ND
Dr. Colin MacLeod, ND
Updated January 10, 2026 6 min read
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Lead (Pb) is a very stubborn metal. When a lead particle enters our body it readily replaces a calcium or zinc particle and becomes stuck very firmly within our tissue. In nature, lead is an uncommon heavy metal which is found at a concentration of only 10 parts per million in the earth’s crust1. However, over the past few decades lead has become much more prevalent in day-to-day life and toxicity has become a common problem as a result.

Symptoms of Lead Toxicity

Lead-poisoned adults may develop anemia, digestive issues, kidney compromise, sexual sterility, convulsions2, depression, anxiety and memory loss3, while children may suffer from abdominal pain, constipation, nausea, reduced IQ, limited growth and delayed sexual maturation4. However, symptoms typically don’t present until very high levels of lead have accumulated in the body5.

Sources of Exposure

Because of its moldability, resistance to corrosion and low cost, lead is a widely used metal in industry and manufacturing processes. Lead toxicity most often occurs from exposure to contaminated soil, water, plumbing, lead paint and car batteries6. Lead enters the body most through inhalation or ingestion of contaminated dust. Lead affects both adults and children but children are especially vulnerable due to their significantly increased absorption of the metal7.

Lead in Nova Scotia

Peeling lead paint from an older home

Significant sources of lead exposure to Nova Scotians include contaminated drinking water, the manufacture of batteries and paint from some older homes.8 There has been media attention over the past few years on lead contamination of drinking water at Acadia University9 and Kings County Academy.10 The death of eagles from lead poisoning here in Nova Scotia has also been reported by the CBC11 and The Chronicle Herald.12

Chelation Therapy

Chelating agents are used in selected cases of confirmed, clinically significant lead poisoning. The choice of agent and treatment setting depends on the measured blood lead concentration, symptoms, age, exposure history, kidney function and public-health or medical-toxicology guidance. Removing the source of exposure is essential. Chelation is not appropriate solely because of nonspecific symptoms or suspected historical exposure.

Safety of Chelation

Chelation has meaningful risks, including reactions to the agent, changes in blood pressure, mineral or electrolyte disturbances, kidney injury and complications related to intravenous administration. Appropriate laboratory confirmation, clinical oversight and monitoring are required. Suspected lead poisoning should be assessed through established medical and public-health pathways.

Assessing For Lead Toxicity

Blood tests

Venous blood lead concentration is the primary laboratory test used to assess lead exposure and guide follow-up. Results must be interpreted with the exposure history, symptoms and applicable public-health thresholds. Post-chelator or “provoked” urine testing is not recommended for diagnosing metal toxicity because chelating agents increase urinary metal excretion and there are no validated reference ranges for interpreting the resulting values.

Recent Research Updates

Research continues to confirm the dangers of even low-level lead exposure. A 2018 study in The Lancet Public Health estimated that lead exposure contributes to over 400,000 deaths annually in the United States alone, primarily through cardiovascular disease24. The study found significant associations between blood lead levels and mortality even at levels previously considered “safe.”

The CDC lowered its blood lead reference value for children in 2021 from 5 to 3.5 µg/dL, reflecting growing evidence that lower levels of exposure cause harm25. However, public health experts continue to emphasize that no level of lead exposure is known to be safe, particularly for children’s neurological development.

For people with elevated blood lead levels, management depends on the degree of elevation, symptoms, age and exposure source. Chelation is reserved for selected cases and should not be inferred from cardiovascular risk or nonspecific symptoms.

Lead Toxicity Prevention

There are a few important ways to reduce your exposure to lead, including avoiding contaminated products, being aware of your occupational exposure22 and limiting exposure through drinking water. Reducing lead exposure from drinking water here in Nova Scotia can be achieved through a few simple steps. Use cold water for cooking and drinking, and run the faucet for 5 minutes prior to drinking or cooking if the faucet hasn’t been used for 6 or more hours. Clean all faucet aerators periodically. If pregnant or if you have children, consider using an NSF-53 certified water filter to significantly reduce lead levels in your drinking water.

If you are in the Halifax area you can contact Halifax Water23 to have your drinking water tested for the presence of heavy metals.

Chelation Therapy in Halifax

If you are concerned about lead exposure, an initial visit can review the exposure history, previous results and whether established blood testing or referral is appropriate. Website information cannot determine whether chelation is indicated.

EDTA chelation has also been studied for cardiovascular disease, but the confirmatory TACT2 trial did not demonstrate a reduction in cardiovascular events. It is not a substitute for established cardiovascular care. Learn more in our article on chelation and the TACT trials.

References

  1. Jefferson Lab. “The Element Lead.” It’s Elemental. Web. 27 Jan. 2015.
  2. Staudinger, K, Roth V. Occupational Lead Poisoning. Am Fam Physician. 1998 Feb 15;57(4):719-726.
  3. Mason LH, Harp JP, Han DY. Pb neurotoxicity: neuropsychological effects of lead toxicity. Biomed Res Int. 2014;2014:840547.
  4. Warniment C, Tsang K, Galazka SS. Lead poisoning in children. Am Fam Physician. 2010 Mar 15;81(6):751-7.
  5. Mayo Clinic Staff. “Lead Poisoning.” Symptoms. The Mayo Clinic, 10 June 2014. Web. 28 Jan. 2015.
  6. World Health Organization. “Lead Poisoning and Health.” WHO. Oct. 2015. Web. 26 Jan. 2015.
  7. National Research Council (U.S.). Committee on Toxicology. Recommendations for the Prevention of Lead Poisoning in Children. Washington: National Academy of Sciences, 1976.
  8. Nova Scotia Occupational Health And Safety. “Occupational Health and Safety.” Novascotia.ca. Aug. 2001. Web. 28 Jan. 2015. .
  9. Rhodes, Blair. “Acadia Water Fountains Test Positive for Lead – Nova Scotia – CBC News.” CBCnews. CBC/Radio Canada, 11 Sept. 2013. Web. 28 Jan. 2015.
  10. Delaney, Gordon. “Getting Lead out of School’s Water Still Proves Challenge for N.S. Staff.” The Chronicle Herald. 7 Jan. 2012. Web. 28 Jan. 2015.
  11. CBC News. “Lead in Bullets Poisoning Eagles, Says Vet – Nova Scotia – CBC News.” CBC News. CBC/Radio Canada, 13 June 2012. Web. 28 Jan. 2015.
  12. Gorman, Michael. “Lead Poisoning Threatens Eagles.” The Chronicle Herald. 3 Jan. 2012. Web. 28 Jan. 2015.
  13. Lamas GA, Goertz C, Boineau R, Mark DB, Rozema T, Nahin RL, Lindblad L, Lewis EF, Drisko J, Lee KL; TACT Investigators. Effect of disodium EDTA chelation regimen on cardiovascular events in patients with previous myocardial infarction: the TACT randomized trial. JAMA. 2013 Mar 27;309(12):1241-50.
  14. Shannon, M. Severe Lead Poisoning in Pregnancy. Ambulatory Pediatrics 2003;3:37 39.
  15. National Center for Environmental Health. “What Do Parents Need to Know to Protect Their Children?” Centers for Disease Control and Prevention. 19 June 2014. Web. 28 Jan. 2015.
  16. Ha M, Kwon HJ, Lim MH, Jee YK, Hong YC, Leem JH, Sakong J, Bae JM, Hong SJ, Roh YM, Jo SJ. Low blood levels of lead and mercury and symptoms of attention deficit hyperactivity in children: a report of the children’s health and environment research (CHEER). Neurotoxicology. 2009 Jan;30(1):31-6.
  17. Eum KD, Korrick SA, Weuve J, Okereke O, Kubzansky LD, Hu H, Weisskopf MG. Relation of cumulative low-level lead exposure to depressive and phobic anxiety symptom scores in middle-age and elderly women. Environ Health Perspect. 2012 Jun;120(6):817-23.
  18. Work Group of the Advisory Committee on Childhood Lead Poisoning Prevention. “A Review of Health Effects of Blood Lead Levels. 23 Feb. 2004. Web. 28 Jan. 2015.
  19. Lee WR, Moore, MR. Low level exposure to lead. BMJ. Sep 15, 1990; 301(6751): 504–506.
  20. Olympio KP, Gonçalves C, Günther WM, Bechara EJ. Neurotoxicity and aggressiveness triggered by low-level lead in children: a review. Rev Panam Salud Publica. 2009 Sep;26(3):266-75.
  21. Agency for Toxic Substances & Disease Registry. “Environmental Health and Medicine Education.” Lead (Pb) Toxicity: What Tests Can Assist with Diagnosis of Lead Toxicity? N.p., 20 Aug. 2007. Web. 28 Jan. 2015.
  22. “Code of Practice: Working with Inorganic Lead.” Nova Scotia Labour And Workforce Development. N.p., 12 June 2010. Web. 28 Jan. 2015.
  23. “Water Quality and Lead.” Official Website of Halifax’s Municipal Government. Web. 28 Jan. 2015.
  24. Lanphear BP, Rauch S, Auinger P, Allen RW, Hornung RW. Low-level lead exposure and mortality in US adults: a population-based cohort study. Lancet Public Health. 2018;3(4):e177-e184.
  25. Centers for Disease Control and Prevention. Blood Lead Reference Value. CDC. Updated October 2021.