Radiological
Radium-226 in your water
Is Radium-226 in drinking water dangerous?
It depends on the level and how long you're exposed. The EPA legal limit (MCL) for Radium-226 is 5 pCi/L. Meeting the legal limit isn't the same as zero risk — test your water to know your level.
How do you remove Radium-226 from water?
Radium-226 is treated by Water Softener and Reverse Osmosis. Choose a system independently certified to NSF/ANSI standards to reduce Radium-226, and test your water first to confirm the level.
Source: EPA MCL / MCLG; WHO guidelines; NSF/ANSI · 2026
Health effects
Radium-226 is a naturally radioactive isotope that seeps from rock into groundwater. Over years of exposure it concentrates in bone and raises the risk of bone and other cancers. It is regulated together with radium-228 under the combined radium standard.
The health-based goal vs. the legal limit
The federal legal limit (MCL) is the maximum allowed by law. The EPA health goal (MCLG) is the level below which no health risk is expected — it is non-enforceable and often stricter than the legal limit.
EPA health goal (MCLG)
No federal health goal set
Federal legal limit (MCL)
5 pCi/L
Source: EPA National Primary Drinking Water Regulations (MCL / MCLG) · 2026
What removes Radium-226
Ion exchange
Water Softener
Swaps the calcium and magnesium that cause hard water for sodium — so scale stops forming.
Look for: NSF/ANSI 44 certification
How it works→Semipermeable membrane filtration
Reverse Osmosis
Pushes water through a fine membrane that removes the dissolved solids most filters miss.
Look for: NSF/ANSI 58 certification
How it works→Where Radium-226 has been found
Radium-226 shows up in the public water record for these cities. Each page has the measured level, the legal limit, and what removes it.
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Is Radium-226 in your water?
Check your city's public record, then book a free 30-minute test to confirm what's in your home.