ClearWaterContaminants › Combined Radium

Radionuclide

Combined Radium in Drinking Water

EPA limits, health effects, and what to do if your water is affected.

EPA Limit (MCL)
5 pCi/L
pCi/L
Category
Radionuclide
Data Source
EPA SDWIS
Updated quarterly

🩨 Health Effects

Long-term exposure to radium above the MCL increases the risk of bone cancer. Radium is a naturally occurring radioactive element that accumulates in bone tissue because it mimics calcium. It decays and produces radon gas.

📍 Sources in Water

Radium occurs naturally in certain rock formations (granite, sandstone) and dissolves into groundwater. Most commonly found in deep groundwater in the Midwest, South, and New England. Rare in surface water systems.

✅ What To Do

Reverse osmosis and ion exchange (water softeners) effectively reduce radium. Point-of-use RO filters at the kitchen tap are practical for drinking water. Radium violations are most common in small community systems and private wells in affected regions.

Check your tap water for Combined Radium

Search your ZIP code to see if your water system has had Combined Radium violations, plus lead testing results and an overall safety grade.

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Data from the EPA's Safe Drinking Water Information System (SDWIS). MCLs reflect minimum federal standards; some contaminants may pose health risks below these thresholds.