Causes and Risk Factors of Lead Poisoning

Despite laws eliminating lead from products such as paint and gasoline, there remains a continued risk of lead exposure and poisoning in the United States.

There has been no better example of this than a 2016 crisis in Flint, Michigan in which over 100,000 residents were exposed to lead due to outdated plumbing in the public water system and insufficient water treatment facilities. In the year following the crisis, many children screened had high levels of lead in their body.

Lead exposure can occur from contact with lead in the air, household dust, soil, water, and commercial products. Continued exposure over the course of months or years can eventually lead to lead poisoning.

lead poisoning causes and risk factors
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Risk Factors

According to a report from the Agency for Toxic Substances and Disease Registry (ATSDR), children are at the greatest risk of lead poisoning for several reasons:

  • They are more likely to ingest lead particles due to hand-to-mouth behaviors.
  • They absorb ingested lead more readily than adults do.
  • They have a faster respiration rate and inhale more airborne particle by body mass.
  • They are closer to the ground and are more likely to inhale particles in the soil or on the ground.

Other factors can place both adults and children at risk. Chief among them is living in an unrenovated building built before 1978 (the year when lead was officially banned from paint products).

This factor alone translates to a higher risk of lead poisoning among poor, ethnic communities where substandard housing is commonplace.

According to the CDC, African-American children are four times more likely to get lead poisoning than white children. 

Here are the eight most common sources of lead exposure in the United States.


Paint may be the most recognized source of lead exposure in the United States. According to a report issued by the U.S. Environmental Protection Agency (EPA), the risk is significant in any home built before 1978 and tends to increase the older the house is. 

EPA Findings on Lead Paint in Homes

According to the EPA, leaded paint is likely to be found in:

  • 24% of houses built between 1960 and 1977
  • 69% of houses built between 1940 and 1959
  • 87% of houses built before 1940

The hazard of exposure is greatest wherever old paint is peeling, chipping, chalking, cracking, or damp. This is especially true around window frames, doors, railings, porches, and banisters where hands can more readily pick up paint chips and particles.

While lead paint buried beneath new paint is not a problem, any home renovation that involves the scraping of plaster or paint can provide an opportunity for exposure. While wet mopping, vacuuming, and face masks can greatly reduce the risk, the EPA recommends that you remove any children or pregnant women from the home until the renovations are complete.


Lead is a naturally occurring metal identified by its bluish-gray coloration.

The natural lead concentration in soil is generally low and not considered a hazard. The exception is urban soil contaminated with peeling paint from older houses or buildings.

Soils adjacent to heavy traffic areas are also a concern, with some studies suggesting that between four and five million tons of lead used in gasoline still remain in soil and dust.

If your house is older, the EPA recommends that you check the exterior for flaking or deteriorating paint.

If you find evidence of lead in the soil around your home, you can avoid tracking it inside by using doormats inside and outside of the house and removing your shoes before entering.

If you can't afford to repaint your home, you should consider planting bushes close to the house, so that kids are discouraged from playing in the soil.


While lead is not usually found in lakes and other natural water supplies, it can enter the water supply and household plumbing if older pipes are not replaced and begin to corrode. This is even true if the pipes themselves are not made of lead.

Up until 1986, metal pipes were commonly joined using leaded solder. So, even if the pipes themselves contain less than 8 percent lead (the acceptable threshold under the current law), the solder used to connect them could have inordinately high levels of lead. Unless the water is tested, there is really no way to know.

Even with increased efforts to surveil the public water supply, the EPA says that drinking water makes up around 20% of a person's exposure to lead.

There are other sources of lead in our water that also get missed. One such example is drinking fountains in older schools which are not subject to inspection in many states. In 2017, a San Diego grade school discovered this only after a therapy dog refused to drink water from a fountain.

Ceramics and Crystal

Some paints and glazes used to decorate pottery and ceramics contain significant levels of lead and, as such, are not intended for use on dinnerware or serving dishes. When food or drinks are placed in them, lead can readily leach out and be ingested.

This is especially true of older pottery and ceramicware that are more likely to have areas of chipping and deterioration. Of particular concern is imported traditional pottery which may be labeled "lead-free" but still contain excessive levels of the extractable metal. A 2010 warning issued by the U.S. Food and Drug Administration advised consumers of the risk after high levels of lead were found in imported ceramicware from Mexico.

If you have leaded glassware, the EPA advises against using it either on a daily basis or for the storage of foods or liquids.

Leaded crystal is also a concern. Decanters are especially problematic since wine, liquor, and acidic juices can promote the transfer of lead to the decanted fluid.

Traditional Medications and Comestibles

Traditional medicines should warrant concern as they are largely unregulated in the United States.

Ayurvedic medications and folk remedies imported from India, Southeast Asia, the Middle East, the Dominican Republic, and Mexico are of special concern as there are no means to assess how the ingredients were sourced, how they may have been refined or treated, and under what conditions they were manufactured.

In fact, lead, sulfur, arsenic, copper, and gold are intentionally added to many Ayurvedic remedies under the belief that they offer health benefits, say researchers from the Yale University School of Medicine.

Folk Medicines With High Risk of Lead

Among the folk medicines the CDC has identified as having a high risk of lead exposure:

  • Azarcon and greta: Hispanic traditional medicines taken for an upset stomach
  • Ba-baw-san: Chinese herbal remedy used to treat colic
  • Daw tway: digestive aid used in Thailand and Myanmar
  • Ghasard: Indian folk medicine used as a tonic

Moreover, it's not just medications that are suspect; imported candies and cosmetics are also a concern.

Imported candies from Mexico, Malaysia, China, and India (especially those flavored with tamarind, chili powder, or certain salts) should be avoided as these frequently have elevated levels of lead. The same applies to traditional cosmetics, such as Kohl used in parts of the Middle East, North Africa, and Southeast Asia to outline the eyes.

Even imported everyday cosmetics like lipsticks and eyeliners should be avoided as they are not subject to the strict pre-market testing prescribed under the U.S. Federal Food, Drug, and Cosmetic Act.

Occupations and Hobbies

According to the EPA, the majority of lead poisoning cases in adults are a result of workplace exposure. Anyone who engages in these professions or activities can potentially bring lead into their homes.

Industries in which the risk of lead exposure is high include:

  • Auto body repair and repainting
  • Ammunition and bullet manufacturing
  • Battery manufacturing and recycling
  • Construction (particular restoration or retrofitting)
  • Firing range instruction
  • Glass or crystal manufacturing
  • Lead smelting
  • Lead weight manufacturing
  • Meal recycling
  • Mining
  • Pewter manufacturing
  • Plumbing and radiator repair
  • Shipbuilding
  • Steel welding

If you are frequently exposed to lead, you can reduce exposing others by showering or changing your clothes and shoes before entering your home or touching family members. 

Hobbyists who engage the following activities are also at risk:

  • Artistic painting
  • Auto repair
  • Electronics soldering
  • Glazed pottery making
  • Metal soldering
  • Molding of bullets, slugs, or fishing sinkers
  • Stained-glass making
  • Shooting firearms


Toys manufactured in countries where the use of lead is not restricted may also pose a risk. The worrying part is that there is often little way of knowing whether an imported toy is safe since there are no systems in place to routinely screen them.

Since new import regulations were enacted by the U.S. Product Safety Commission in 2008, the number of lead-related toy recalls has dropped from 19 in 2008 to zero in 2017.

It's not just imported toys that are of concern: antique toys, lunchboxes, and even old crayons may contain excessive amounts of lead.

As such, it may be better to keep these objects in a display case or to throw them out if they are not considered a keepsake.


When lead gets into your body, it can accumulate in many tissues, including those of the brain, intestines, kidneys, liver, and bones.

During pregnancy, lead deposits in the bones can be especially problematic as metabolic changes can trigger the transient bone loss of the hip. If this happens, lead can leach out into the system and raise the toxicity to hazardous levels.

If a fetus is exposed to lead there is an increased risk of low birth weight, preterm birth, and even miscarriage.

The daily use of a calcium supplement during pregnancy may greatly counteract the effect.

Frequently Asked Questions

  • What causes lead poisoning?

    Lead poisoning occurs when you absorb too much lead by breathing or swallowing a substance with lead in it. Lead has no biological role and even a small amount can cause harm to almost every organ system, including the kidneys and reproductive organs. Because lead is structurally similar to calcium, it can cross the blood-brain barrier and cause damage to the brain.

  • What are common sources of lead poisoning?

    Common sources of lead poisoning in the United States include:

    • Occupational lead exposure
    • Lead paint, especially in houses built before 1978
    • Soil, particularly near roadways and deteriorating older buildings
    • Water, typically from water systems with lead piping
    • Imported glazed ceramicware
    • Imported Ayurvedic and traditional Chinese medicines
    • Contact with bullets, lead tackle, solder, and ceramic glazes
  • Who is at greatest risk of lead poisoning?

    Children are at the greatest risk of lead poisoning because of their smaller size. They are also more likely to put objects in their mouth that contain lead, such as paint chips, metal jewelry, or toys made for pets.

  • What occupations place you at risk of lead poisoning?

    Occupational lead exposure is the most common route of exposure in adults. Occupations in which lead exposure is possible include:

    • Auto repair
    • Battery manufacturing
    • Construction demolition or renovation
    • Glass manufacturing
    • Gunsmithing and firing range instruction
    • Lead mining and smelting
    • Plastic manufacturing
    • Plumbing
    • Recycling
    • Rubber manufacturing
    • Solid waste incinerating
    • Welding
12 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1.  U.S. Department of Health and Human Services. Agency for Toxic Substances and Disease Registry. Lead Toxicity: Who Is at Risk of Lead Exposure?

  2. Environmental Protection Agency. Protect your family from exposures to lead.

  3. Schwarz K, Pouyat RV, Yesilonis I. Legacies of Lead in Charm City's Soil: Lessons from the Baltimore Ecosystem Study. Int J Environ Res Public Health. 2016;13(2):209. doi:10.3390/ijerph13020209

  4. KQED Science. Lead in the Drinking Fountain? California Schools Must Now Test For It

  5. U.S. Food & Drug Administration. Guidance for Industry: Safety of Imported Traditional Pottery Intended for Use with Food and the Use of the Term "Lead Free" in the Labeling of Pottery/Proper Identification of Ornamental and Decorative Ceramicware

  6. Gunturu KS, Nagarajan P, Mcphedran P, Goodman TR, Hodsdon ME, Strout MP. Ayurvedic herbal medicine and lead poisoning. J Hematol Oncol. 2011;4:51. doi:10.1186/1756-8722-4-51

  7. National Institute for Occupational Safety and Health. Jobs that may have lead exposure.

  8. Centers for Disease Control and Prevention. Lead Hazards in Some Holiday Toys and Toy Jewelry

  9. American College of Obstetricians and Gynecologists. Lead Screening During Pregnancy and Lactation

  10. Rădulescu A, Lundgren S. A pharmacokinetic model of lead absorption and calcium competitive dynamics. Sci Rep. 2019;9(1):14225. doi:10.1038/s41598-019-50654-7

  11. Dignam T, Kaufmann RB, LeStourgeon L, Brown MJ. Control of lead sources in the united states, 1970-2017: public health progress and current challenges to eliminating lead exposure. J Pub Health Manag Pract. 2019;25(1):S13-22. doi:10.1097/PHH.0000000000000889

  12. Mayans L, Lead poisoning in children. Am Fam Physician. 100(1):24-30.

By Amber Yates, MD
Amber Yates, MD, is a board-certified pediatric hematologist and a practicing physician at Baylor College of Medicine.