Radon in Drinking Water: Health Risks, Sources, and How to Remove It
Radon is a radionuclide contaminant that can be found in drinking water. As a radioactive substance, it is subject to regulation with an EPA Maximum Contaminant Level (MCL) of 300 pCi/L. Understanding its presence and potential impacts is an important part of managing water safety.
Health Effects
Exposure to radon in drinking water is associated with an increased risk of cancer. Consuming water containing this radionuclide contaminant can lead to long-term health concerns related to this risk. It is important to monitor and address elevated levels to mitigate these potential health effects.
How Radon Gets Into Tap Water
Radon in water originates from the natural decay of uranium in soil. As uranium breaks down naturally in the ground, it releases radon which can then enter drinking water sources. This natural process is the primary source of this radionuclide contaminant in water.
How to Remove Radon From Your Water
Several treatment options are available to reduce radon levels in drinking water. Effective treatment methods include aeration systems and granular activated carbon filtration. These treatment systems are commonly utilized to address this radionuclide contaminant in household water.
Should You Test Your Water?
To check for radon, you can review your local utility's consumer confidence report or search for testing information on WaterQ. Private well owners may also consider testing their water supply if they suspect radon contamination. You can also look up your local water system on WaterQ or check the Radon data page for reported levels in your area.
Frequently Asked Questions
Is Radon dangerous in drinking water?
Yes, exposure to radon in drinking water is associated with an increased risk of cancer. Because it is a radionuclide, managing its levels is important for long-term health protection. Ensuring your water remains below the EPA MCL of 300 pCi/L helps reduce this health risk.
How does Radon get into tap water?
Radon gets into tap water through the natural decay of uranium in soil. As the uranium decays, radon is released and can migrate into drinking water supplies.
How can I remove Radon from my water?
Radon can be removed from drinking water using treatment methods such as aeration or granular activated carbon. These treatment systems are effective at reducing radon levels in your water.
Source: EPA National Primary Drinking Water Regulations and WaterQ National Database. For more contaminants, visit our contaminant library.
What actually removes radon
Radon breaks the usual rules because it is a dissolved gas, not a dissolved solid — reverse osmosis, the answer to most well-water problems, does not remove it. The two real options are aeration, which strips the gas out and is the more effective choice, and a large granular activated carbon tank, which works at lower concentrations but accumulates radioactivity and eventually needs careful disposal. Both are whole-house installations, because the exposure that matters happens in the shower rather than at the glass.
Works
- Basic activated carbon (NSF 42)Fixes taste and smell. Does not remove any health-regulated contaminant.
Will not fix this
- Reverse osmosis (NSF 58)
- Ion-exchange water softener
- UV disinfection (NSF 55)
- Carbon certified for lead (NSF 53)
Test before you buy.Radon can't be seen, tasted or smelled, and the right hardware depends on the concentration you actually have. A certified lab test costs a fraction of the wrong filtration system. Start with your local water quality report, and get a mail-in lab test if you're on a private well.
Options that carry the right certification
Ordered cheapest-adequate first. Prices are indicative bands and move often.
| Product | Certification | Upfront | Per year | |
|---|---|---|---|---|
| SpringWell CF1 Whole-House CarbonWhole house | Catalytic carbon media, which is the grade required to reduce chloramine.Catch:Whole-house carbon protects showers and appliances but is not a substitute for a point-of-use lead or PFAS filter at the tap. | $900–1,400 | $0–100 | Check price |
Certification listings change. Before buying, confirm the current listing for the exact model in the NSF certified products database — a manufacturer's marketing page is not a certification. WaterQ earns a commission on purchases made through these links at no extra cost to you; see our affiliate disclosure. This is general information, not medical or engineering advice.
For a full breakdown of certifications, running costs and the models worth considering, see our buying guide for radon.