About This Report
“My Children Have Been Poisoned”
June 15, 2011

Appendix I: Lead Poisoning Symptoms, Effects on Health, and Treatment

Lead is a heavy metal that naturally forms in the Earth’s crust. It is highly toxic to humans when ingested or inhaled. Although lead was previously considered safe at low levels, lead is now considered unsafe at any level.[256] Elevated lead levels damage the brain, kidneys, and blood cells, which may result in anemia, deficits in IQ, high blood pressure, coma, or death. Because lead poisoning may not necessarily manifest in obvious symptoms, it can often go unrecognized.[257] Today, the US Centers for Disease Control and Prevention defines lead poisoning as any blood lead concentrations over 10 micrograms per deciliter. Although the effects of lead poisoning vary according to blood lead levels, the World Health Organization now considers lead unsafe at any level.[258]

Pregnant women and children are particularly vulnerable to lead poisoning. In pregnant women, it can cause premature birth, low birth weight, or damage the fetus’ developing brain.

Children are especially at risk for lead poisoning because they tend to absorb up to 50 percent of lead that they are exposed to, compared to 10-15 percent for adults.[259] The potential damage of lead poisoning in children is high because lead affects the development of their nervous and digestive systems. Virtually every organ in children is susceptible to damage from lead poisoning.[260] Infants’ and young children’s propensity to explore the world through their mouths or play in what may be lead contaminated areas increases their likelihood of ingesting or inhaling lead in dust and dirt.[261]

In children, elevated blood lead levels can cause: [262]

  • reduced IQ and attention span
  • reading and learning disabilities
  • behavioral problems
  • hearing loss
  • impaired growth and visual and motor functioning
  • anemia
  • brain, liver, kidney, nerve, and stomach damage
  • coma and convulsions
  • death

The adverse effects of lead poisoning intensify with repeated exposure, and the long-term effects of lead poisoning cause irreversible damage.

Chelation therapy is the most common treatment for lead poisoning. It uses EDTA (ethylenediaminetetraacetic acid), a synthetic amino acid, to bind and thus neutralize lead and other heavy metals in the bloodstream, forming a compound that is then dispelled in urine.[263] The process generally takes one to three hours and can be administered through intravenous injection or orally in the form of dimercaptosuccinic acid. Chelation therapy can also be used to eliminate other heavy metals from the body including mercury, arsenic, aluminum, chromium, cobalt, manganese, nickel, and zinc.[264]

Side effects of chelation therapy can include headaches, nausea, diarrhea, fatigue, joint pain, cramps, and skin irritation.[265] More serious side effects include kidney toxicity, bone marrow depression, shock, low blood pressure (hypotension), convulsions, disturbance of regular heart rhythm, allergic heart reaction, and respiratory arrest.[266] As chelation treatment may also deplete useful elements in the body, such as iron, zinc, and copper, dietary supplements and vitamins are recommended to be taken during treatment as well.

According to the US Centers for Disease Control and Prevention, environmental impact assessments should be performed in tandem with lead detoxification treatments in order to identify and eliminate the source of contamination. Unless the exposure to lead is mitigated, chelation therapy may not be fully effective, and instead, chelating agents may in fact facilitate the absorption of lead in the gastrointestinal tract.[267]

[256] U.S. Department of Health and Human Services, Agency for Toxic Substances and Disease Registry, “Lead,” August 2007, http://www.atsdr.cdc.gov/toxfaqs/tf.asp?id=93&tid=22 (accessed November 4, 2010); Helen Gavaghan, “Lead, Unsafe at any Level,” Bulletin of the World Health Organization, vol. 80, no. 1 (2002), http://whqlibdoc.who.int/bulletin/2002/Vol80-No1/bulletin_2002_80%281%29_82-82.pdf (accessed November 4, 2010).                                                                                              

[257] U.S. Department of Health and Human Services, Agency for Toxic Substances and Disease Registry, “Lead: Topic Home,” undated, http://www.cdc.gov/lead/ (November 4, 2010).

[258] Helen Gavaghan, “Lead, Unsafe at any Level,” Bulletin of the World Health Organization, vol. 80, no. 1 (2002), http://whqlibdoc.who.int/bulletin/2002/Vol80-No1/bulletin_2002_80%281%29_82-82.pdf (accessed November 4, 2010).

[259] Ibid.

[260] Ibid.

[261] Ibid.

[262]United Nations Children’s Fund and United Nations Environment Program, “Childhood Lead Poisoning: Information for Advocacy and Action,” 1997, http://www.chem.unep.ch/irptc/Publications/leadpoison/lead_eng.pdf (accessed November 4, 2010).

[263] University of Maryland Medical Centre, “Ethylenediaminetetraacetic Acid,” 2009, http://www.umm.edu/altmed/articles/ethylenediaminetetraacetic-acid-000302.htm (accessed November 4, 2010).

[264] Ibid.

[265]Chelation.org, “Side Effects of Chelation,” 2010, http://www.chelation.org/side-effects-of-chelation(accessed November 4, 2010).

[266] American Heart Association, “Questions and Answers About Chelation Therapy,” 2010, http://www.americanheart.org/presenter.jhtml?identifier=3000843 (accessed November 4, 2010).

[267] U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Environmental Health, Agency for Toxic Substances and Disease Registry, Division of Emergency and Environmental Health Services, “ Development of an Integrated Intervention Plan to Reduce Exposure to Lead and Other Contaminants in the Mining Center of La Oroya, Perú,” May 2005, http://cdc.gov/nceh/ehs/Docs/la_oroya_report.pdf (accessed November 4, 2010).