Lead is one of the few drinking-water contaminants with no known safe level of exposure, and it's especially harmful to infants and young children, where it can affect brain development. The tricky part: lead usually isn't in the water when it leaves the treatment plant — it gets picked up on the way to your faucet.

How lead gets into tap water

Lead leaches from lead service lines (the pipe connecting the water main to your home) and from older brass fixtures, faucets, and lead solder. Homes built before 1986 are most likely to have lead somewhere in the plumbing. Corrosive water and hot water make leaching worse.

The health risks

Per the CDC, there is no safe blood lead level in children; exposure is linked to lower IQ, attention problems, and developmental delays. In adults, lead is associated with high blood pressure and kidney issues. Because effects accumulate and often show no symptoms, the goal is to minimize exposure rather than wait for warning signs.

What the rules require

The EPA's Lead and Copper Rule, strengthened by the 2024 Lead and Copper Rule Improvements, lowered the action level and requires water systems to inventory and replace lead service lines — most within a decade. That's national progress, but replacement takes years, so your home may still have a lead line in the meantime.

How to check and protect your household

  • Ask your utility whether your service line is lead — many now publish service-line inventories.
  • Test your water through a certified lab; lead is invisible and tasteless, so testing is the only way to be sure.
  • If lead is a concern, use a filter certified to NSF/ANSI 53 for lead — see how to choose a water filter.
  • Run the tap to flush standing water, and use only cold water for drinking, cooking, and making formula (hot water leaches more lead).

The bottom line

Lead is a serious but manageable risk. Find out whether your home or system has lead exposure via your utility's inventory and your water report, confirm with a certified test if you're unsure, and use a lead-certified filter and cold-water habits while service-line replacement catches up. If you have young children or are pregnant, prioritize testing.