Lead in drinking water is largely invisible: colorless, odorless, and tasteless. Yet it's one of the most dangerous contaminants because it causes irreversible neurological damage in children, even at very low levels. After Flint, Michigan, national attention turned to aging water infrastructure, but the problem is far more widespread than any single city.
How Lead Gets Into Drinking Water
Unlike most contaminants, lead doesn't come from a water source or treatment plant. It leaches from household plumbing. The three main sources are:
- Lead service lines: pipes connecting the water main to your home, common in homes built before 1986
- Lead-based solder: used in copper pipe joints until banned in 1986
- Lead-containing fixtures: faucets, fittings, and valves (the Safe Drinking Water Act only required "lead-free" fixtures in 2014, meaning less than 0.25% lead)
Corrosive water accelerates leaching. Water that is low in pH, low in hardness, or high in chloramines is more likely to corrode pipes and pull lead into the water.
EPA's Lead and Copper Rule
The EPA regulates lead under the Lead and Copper Rule (LCR), most recently revised in 2021. Key numbers:
- Action Level (AL): 15 ppb. If 10% of "first-draw" samples from high-risk homes exceed this, utilities must take corrective action. Note: the 2024 Lead and Copper Rule Revisions (LCRR) are phasing the action level down to 10 ppb by 2027.
- Maximum Contaminant Level Goal (MCLG): 0 ppb, because no level of lead exposure is safe.
- The 2021 revision requires utilities to replace all lead service lines within 10 years, identify all lead service lines by 2024, and notify customers within 24 hours of a lead exceedance
See which states have utilities with lead violations on SafeWater's state rankings →
Health Effects of Lead Exposure
Lead exposure has no safe threshold for children. Effects include:
- Reduced IQ and cognitive development (even at 1–2 ppb)
- Behavioral problems, ADHD-like symptoms
- Impaired hearing and growth
In adults, lead causes high blood pressure, kidney disease, and reproductive problems. Pregnant women are especially vulnerable because lead transfers to the fetus through the placenta.
How to Test for Lead
Your utility tests water at the treatment plant, not at your tap. To know what's coming out of your faucet, you must test your own water. Steps:
- Contact your water utility (many offer free lead test kits)
- Use a state-certified lab (find one at epa.gov/dwlabcert)
- Collect a "first-draw" sample: water that has sat in pipes for at least 6 hours
- Also collect a "flush" sample to distinguish between service line and household plumbing lead
Reducing Lead Exposure
- Run cold water for 30–60 seconds (or until noticeably colder) before drinking or cooking
- Always use cold water for cooking and infant formula (hot water leaches more lead)
- Install an NSF/ANSI 53-certified filter (for lead reduction); reverse osmosis also works
- Replace lead service lines and old fixtures if possible
See our full filtration guide: Best Water Filters for Removing Contaminants →
View lead contaminant data: Lead contaminant page →