The Health Impacts of Elevated Levels of Lead

By Todd Maderis


The recent devastating effects of lead-tainted water in Flint, Michigan created a public awareness that lead has adverse health consequences. But illness caused by lead is not just an issue in Flint, nor is lead the only toxic metal that impacts the health of both children and adults. It is estimated that at least 50% of the population has blood lead levels high enough to be associated with disease. 

Lead is considered the great success story in American environmental medicine because it was banned from paint in 1978 and from gasoline in 1995, and lead levels in humans has declined ever since. However, lead remains widespread in the environment and continues to affect millions of American each year.

Sources of Lead

In addition to gasoline and paint, lead can currently be found in the following sources. [1]

  • Water – Almost 2000 water systems across the U.S. have elevated lead levels, especially systems in old municipalities, like Flint, that switched from chlorine to chloramine as disinfectant; chloramine is less corrosive to pipes, but releases lead)
  • Dust (inside and outside)
  • Some Ayuverdic and patented Chinese herbal remedies
  • Maternal-fetal exchange (blood-lead levels increase during pregnancy, and more is released to the fetus)
  • Lead-containing dishware and cookware
  • PVC (polyvinyl chloride, a synthetic plastic) products
  • Hobbies (arts/painting, lead glass, fishing weights, bullets)
  • Certain toys
  • Cosmetics

What Effect Does Lead Have on Humans?

Lead binds to red blood cells, then is distributed to soft tissue, and then is moved to bones, where most of it is stored. It stays in bones for years, meaning that health problems associated with this toxic metals are not always acute; they are often the result of cumulative exposure. Therefore proper testing of lead (and other metals) requires a metal mobilization test.  Blood are hair levels only reflect recent exposure. 

Symptoms Caused by Cumulative Exposure Lead

  • Decreased cognition and IQ – processing speed, executive function and verbal memory can all be affected by elevated lead levels.[2, 3, 4, 5, 6] Cognitive decline is not associated with blood levels (acute exposure), but with bone lead levels which is determined by metal mobilization test.
  • ADHD (Attention Deficit Hyperactivity Disorder), impulsivity, oppositional conduct [7]
  • Parkinsonism  - Risk of Parkinson’s is more than double with higher lead exposure [8, 9]

Symptoms Caused by Recent Exposure to Lead

  • Loss of balance [10]
  • Hearing loss [11]
  • Depression and anxiety [12]
  • Cardiovascular disease, high blood pressure and elevated homocysteine [13, 14, 15]
  • Pregnancy induced high blood pressure [16]
  • Gout [17]
  • Kidney disease [18]
  • ALS (Lou Gehrig’s disease) [19]
  • Altered intestinal microbiome [20, 21]
  • Immune system dysfunction [22, 23]
  • Fatigue
  • Headaches [24]

Lead Toxicity and Lyme disease

Since lead contributes to immune dysfunction, and can present with fatigue, brain fog and headaches, lead toxicity needs to be ruled out as a concomitant variable in patients diagnosed with Lyme disease.  In addition, lead can cause numbness, tingling and weakness in hands and feet [25]; another common symptom in tick-borne illness.

What Can You Do to Protect Yourself from Lead?

Check out the Environmental Working Group’s (EWG) Tap Water Database and consider installing a quality water filtration system in your house.  Since lead is stored in trabecular bone, perimenopausal and menopausal women have an increased risk for high lead levels due to bone break down caused by low estrogen.  Women on hormone replacement therapy are more protected from a lead burden since their bones do not lose bone density at the same rate as women not on hormone replacement therapy.

Lead can cause acute illness, but cumulative lead poses the greatest risk to a larger population.  Many of our patients with chronic illness present with one or more of the above symptoms, so proper testing is most important to determine if elevated levels of lead is affecting your health.