Radon
Health Effects
Lung cancer is essentially the only health effect associated with exposure to radon and radon progeny. Many scientists believe that long-term exposure to elevated levels of radon and radon progeny in air increases your chance of getting lung cancer. Smoking cigarettes greatly increases your chance of developing lung cancer if you are exposed to radon and radon progeny at the same levels as people who do not smoke. Radon in water is primarily a concern because it escapes into indoor air when water is used for showering, laundry and dishwashing.
Source: ATSDR — ToxFAQs / Toxicological Profile (retrieved 2026-07-27)
On a private well?
This page covers Radon in public water systems. Private wells are unregulated and not tested by anyone unless you arrange it.
Radon in private well water →Common Sources
- Radon is produced by the radioactive decay of radium in rock, soil and groundwater
- Groundwater from wells drilled into radium-bearing bedrock carries dissolved radon, which is released into indoor air when the water is used
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Where is Radon Found?
Radon has been detected above EPA health guidelines in 113 cities serving 26.2M people across the US.
and 108 more cities
Contaminant Type
Radon is classified as a Radionuclides contaminant.
Related Radionuclides Contaminants
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