1. What is Radon?
Radon is a radioactive gas released from the normal decay of uranium in rocks and soil. It is an invisible, odorless, tasteless gas that seeps up through the ground and diffuses into the air. In a few areas, depending on local geology, radon dissolves into ground water and can be released into the air when the water is used. Radon gas usually exists at very low levels outdoors. However, in areas without adequate ventilation, such as underground mines, radon can accumulate to levels that substantially increase the risk of lung cancer.
2. How is the general population exposed to radon?
Radon is present in nearly all air. Everyone breathes radon in every day, usually at very low levels. However, people who inhale high levels of radon are at an increased risk for developing lung cancer. Radon can enter homes through cracks in floors, walls, or foundations, and collect indoors. It can also be released from building materials, or from water obtained from wells that contain radon. Radon levels can be higher in homes that are well insulated, tightly sealed, and/or built on uranium rich soil. Because of their closeness to the ground, basement and first floors typically have the
highest radon levels.
3. How does Radon cause cancer?
Radon decays quickly, giving off tiny radioactive particles. When inhaled, these radioactive particles can damage the cells that line the lung. Long-term exposure to radon can lead to lung cancer, the only cancer proven to be associated with inhaling radon.
4. How can people know if they have an elevated level of radon in their homes?
Testing is the only way to know if a person's home has elevated radon levels. Indoor radon levels are affected by the soil composition under and around the house, and the ease with which radon enters the house. Homes that are next door to each other can have different indoor radon levels, making a neighbor's test result a poor predictor of radon risk. In addition, precipitation, barometric pressure, and other influences can cause radon levels to vary from month to month or day to day, which is why both short- and long-term tests are available.
Short-term detectors measure radon levels for 2 days to 90 days, depending on the device. Long-term tests determine the average concentration for more than 90 days. Because radon levels can vary from day to day and month to month, a long-term test is a better indicator of average radon level. Both tests are relatively easy to use and inexpensive.