Radon is a naturally occurring radioactive gas that is colorless and odorless. Radon comes from the natural decay of uranium or thorium, elements found in rocks, soils, and water. Radon breaks down quickly, giving off radioactive particles. When inhaled, these radioactive particles can damage cells that line the lung.
Radon gas is in nearly all outdoor air but usually at low levels. Radon is also found in water. A higher radon level in the water supply is more likely when the source is ground water, such as from a private well. Most public water supplies are sourced from surface water, such as lakes, rivers, and reservoirs.
Does radon affect health?
Scientists agree that radon causes lung cancer in humans. Being exposed to radon for a long period of time can lead to lung cancer. In the U.S., radon exposure is the second leading cause of lung cancer after cigarette smoking.
Exposure to the combination of radon gas and cigarette smoke creates an even greater chance of developing lung cancer. The majority of radon-related cancer deaths occur among smokers. However, it is estimated that about 10% of radon-related cancer deaths occur among nonsmokers.
How does radon get into a building or home?
Radon gas can get trapped inside homes and buildings and accumulate in the air. Radon moves up through the ground and can enter a building through cracks in foundations, floors, or walls. It can also be released from building materials and from some ground water. Radon levels are usually highest in basements or crawl spaces. But radon can build up in the air of any home or building whether or not it is sealed or drafty or is new or older.
What can I do about radon?
It is not possible to avoid radon completely. But you can protect your health by testing for radon and taking any recommended steps to lower radon exposure in buildings or homes that have elevated levels. This process, known as radon mitigation, can lower your exposure.
The U.S. Department of Housing and Urban Development (https://www.hud.gov/program_offices/healthy_homes/healthyhomes/radon) recommends these actions to help reduce radon levels in your home: (https://www.nih.gov/health/assets/images/cdc_radonhouse.jpg)
- Increase air flow in your house by opening windows and using fans and vents to circulate air. However, natural ventilation in any type of house is only a temporary strategy to reduce radon.
- Seal cracks in floors and walls with plaster, caulk, or other mate¬rials designed for this purpose.
- Cover an earth floor in crawl spaces with a high-density plastic sheet. A special vent pipe and fan can be used to blow the radon from under the sheet and vent it to the outdoors.
- Monitor radon levels after any fixes to ensure that radon levels are lower.