Lead

Summary

Lead is a potent neurotoxin that impairs children’s intellectual development and alters their behavior and ability to concentrate. There is a strong scientific consensus that any amount of lead exposure during childhood is harmful. The effects of lead exposure during childhood are permanent.

Lead-based paint has historically been the main source of exposure for American children. In recent years, eliminating the use of this paint and removing existing lead-based paint from buildings has significantly reduced children’s exposure. 

But lead contamination of drinking water from old infrastructure like city pipes and household service lines remains a problem for many communities across the U.S., posing a serious risk to children’s health. Since lead levels vary from one building to another, it is difficult to estimate how many people have contaminated water in their homes and schools.

 In 2024, the Environmental Protection Agency lowered the action level for lead in drinking water from 15 to 10 parts per billion, or ppb. The agency set this action level to monitor a water system’s efforts to manage water corrosivity – it is not based on a safe exposure level for children. 

Further, under the federal rules, up to 10 percent of households tested in a single community water system are allowed to exceed the action level, meaning that some households may be disproportionately affected by lead. 

In 2009, the California Office of Health Hazard Assessment set a public health goal for lead in drinking water at 0.2 ppb to protect against harm to children’s brains and nervous systems. This health guideline was based on studies of children showing that an increase of 1 microgram per deciliter of lead in blood correlated with a decrease of one IQ point.

To set the health goal value based on the loss of one IQ point, the agency added a safety factor of three and assumed that water accounted for 20 percent of total lead exposures for a child.

In 2016, the American Academy of Pediatrics advocated for a national commitment to eliminating all sources of lead exposure for children. The organization called for legal requirements mandating that lead be removed from contaminated housing and child care facilities, and for state and local governments to ensure that the water dispensed by water fountains in schools does not exceed lead concentrations of 1 ppb.

EWG urges the federal government to set a more-protective legal limit for lead in drinking water. State and federal drinking water authorities should also require comprehensive, immediate action to monitor houses and apartment buildings for lead contamination and replace old lead water service lines.

How are people exposed to lead, and how does it get into tap water?

Pipes made of lead were once used in hundreds of cities, most commonly in water lines installed before the 1930s. These pipes can be found as part of a city’s main water lines and also in the lines leading from the system to individual homes. In 2016, the American Water Works Association estimated that 15-22 million Americans drink water from a system with lead-based service lines. 

Lead pipes are found inside most homes built before 1930 without updated plumbing.And lead-based plumbing solder was used to join metal water pipes until 1986. 

Leaching of lead from water pipes can be minimized by the addition of water treatment chemicals that reduce corrosivity – but that approach is only partly successful. 

And some water utilities have repeatedly failed to take adequate steps to mitigate the problems caused by old pipes, leading to tragic consequences for residents of cities like Flint, Mich., Newark, N.J. and Washington, D.C. 

In the long term, the only solution is the removal of lead pipes and plumbing fixtures that contain lead, and their replacement with safer alternatives.

What are the toxic effects of lead in drinking water?

There is widespread scientific consensus that exposure to even small amounts of lead during childhood is harmful. 

Lead exposure can alter a child’s behavior, ability to concentrate, memory and learning. Moreover, its harmful effects are irreversible and can continue well into adulthood.

Lead exposure is a particular risk during children’s first six years, when their brains are developing and blood-brain barriers are not yet fully formed. Babies fed formula mixed with unfiltered tap water are at the highest risk of harm from ingesting lead in drinking water.

Children can be exposed to lead in dust or soil contaminated with lead paint, but drinking water is often a significant source of exposure.

Lead exposure can also affect adults’ health. A study published in the Lancet showed that as many as 412,000 American adults face a greater risk of dying from cardiovascular diseases because they were exposed to elevated levels of lead during their lifetimes.

What is the EPA doing about lead in drinking water? 

Revisions to the agency’s Lead and Copper Rule in 2021 required water systems to inventory and report all lead service lines by the fall of 2024. 

In 2023, the EPA estimated that 9.2 million service lines contained lead, but the actual number of lines remains unknown until all water systems complete inventories.

In 2024, the EPA finalized additional improvements to the Lead and Copper Rule, including:

• Requiring a majority of water systems to remove all lead pipes within 10 years. 
• Requiring regular updates to lead service line inventories.
• Lowering the lead action level from 15 to 10 ppb.
• Require water systems to provide certified filters to consumers when lead in their water exceeds that threshold.

The Bipartisan Infrastructure Law, enacted in 2024, expanded the annual EPA funding to states through the Drinking Water State Revolving Fund to include $15 billion in lead service line replacement funds, which could also be used for identification of lead lines.

What can be done to reduce lead exposure from drinking water?

Only a test can show whether the water in your house contains lead. Kits to test water for lead are readily available and may even be provided by your local water utility, government agencies or local public interest organizations. 

Lead tests are particularly important if:

• You have lead-based water lines leading to your house.
• Your local water company has detected lead in water in your neighborhood.
• You drink water from a private well and your local public health department detects lead in well water in your area.

If you have lead in your water, you can reduce it by using a home water filter, flushing cold water pipes each morning and using only cold water for cooking. You can find more guidelines for parents here. 

But these are temporary solutions only. The sole permanent fix to lead contamination in U.S. drinking water is to replace lead-based water pipes in all water systems and homes.

References

American Academy of Pediatrics, Council on Environmental Health. Prevention of Childhood Lead Toxicity. Pediatrics. 20161, 38(1): e20161493. Available at https://pediatrics.aappublications.org/content/138/1/e20161493.

California Office of Environmental Health Hazard Assessment, Public Health Goal for Lead in Drinking Water. 2009. Available at http://oehha.ca.gov/media/downloads/water/chemicals/phg/leadfinalphg042409_0.pdf.

Centers for Disease Control and Prevention, About Lead in Drinking Water. 2024. Available at https://www.cdc.gov/lead-prevention/prevention/drinking-water.html.

D.A. Cornwell et al., National Survey of Lead Service Line Occurrence. Journal of the American Water Works Association, 2016, 108(4): E182-E191. Available at https://awwa.onlinelibrary.wiley.com/doi/10.5942/jawwa.2016.108.0086 

O. Milman and J. Glenza, At Least 33 US Cities Used Water Testing 'Cheats' Over Lead Concerns. The Guardian, 2016. Available at www.theguardian.com/environment/2016/jun/02/lead-water-testing-cheats-chicago-boston-philadelphia.