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Drinking Water Quality - Lead

Lead is a naturally-occurring bluish-gray metal found in small amounts in the earth's crust. Lead can be found in all parts of our environment. Much of it comes from human activities including burning fossil fuels, mining, and manufacturing.

Lead has many different uses. It has been used in paint, batteries, ammunition, metal products (solder and pipes), and devices to shield X-rays. There are also minor amounts in brass plumbing fixtures. Because of health concerns, lead from paints and ceramic products, caulking, and pipe solder has been dramatically reduced in recent years. The United States began to phase out lead as an additive in gasoline in 1975.

Did You Know?
In Massachusetts, all children must be tested for lead in the blood at least one time every year until they are three years old.

Although the main sources of exposure to lead are ingesting paint chips and inhaling lead dust, the U.S. Environmental Protection Agency (U.S. EPA) estimates that 10 to 20 percent of human exposure to lead may come from lead in drinking water. For infants and children, exposure to high levels of lead in drinking water can result in delays in physical or mental development. For adults, it can result in kidney problems or high blood pressure. Infants who consume mostly mixed formula can receive 40 to 60 percent of their exposure to lead from drinking water. The health effects of lead are most severe for infants and children.

Typically, lead enters into drinking water after leaving the local treatment plant or your well. That is, the source of lead in your home's water is most likely from pipes or solder in your home's own plumbing. The most common cause is corrosion, a reaction between the water and the lead in the pipes or solder. Dissolved oxygen, low pH (acidity), and low mineral content in water are common causes of corrosion.

Data Considerations

When reviewing and interpreting drinking water lead data, it is important to take into consideration the following:

  • The data presented are for public water systems only. Residents may have exposure to lead from private well water.
  • Exposure to lead in drinking water depends upon the concentration of lead in the drinking water and the amount of water consumed by the individual. Water consumption varies by such factors as climate and level of physical activity.
  • Many factors can affect whether exposure can lead to a health problem, including level of contamination, amount of water consumed, and the length of time water was contaminated. Some populations may be more susceptible to health problems following exposure, such as pregnant woman, children, and immune suppressed individuals.
  • This website provides a summary of drinking water exceedances by community. Consumer Confidence Reports on public drinking water quality are required to be provided annually to consumers. Your Community Water System should be contacted for this report, which will provide more detailed information on any specific water system exceedances for lead.
  • Community Water Systems (CWSs) can serve areas substantially beyond the boundaries of the principal city/town served.
  • Multiple CWSs can serve the same city/town and multiple cities/towns can be served by a single.
  • For a list of all Massachusetts Community Water Systems and communities served, click here (pdf).

For additional information, please read the FAQ.

Available Data on Water Quality Measures for Lead Exceedance

Click the Explore Maps & Tables link button on this page to access the following measure for lead in drinking water in your community. The most current available data will be shown. Be sure to check the site periodically as new data are added each year.

To protect privacy, no information is shown that could identify an individual home or family.

  • Drinking water exceedances by Community Water System or community and year of exceedance
More About the Data
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