However, water rarely contributes significantly to high indoor-radon levels . High levels of radon have never been found in Utah's public-water supplies, but may be present in well water. If indoor-radon levels are not high, don't be concerned with radon in water. Radon decays into radioactive particles that can be trapped in the lungs when inhaled. These particles release small bursts of energy that damage lung tissue and may lead to lung cancer.
Radon is the second leading cause of lung cancer in the United States.
Only smoking causes more lung-cancer deaths, and smoking combined with radon is a particularly serious health risk. Chances of getting lung cancer are higher from the combination of smoking and radon that from either source alone. Not everyone who is exposed to radon develops the disease, but the chances increase with increasing levels of radon and length of exposure. The amount of time between exposure and onset of the disease is usually many years. Make sure the test kit has passed EPA's testing program or the contractor is EPA qualified.