The EPA has identified radon gas in individual homes as an important source of indoor air pollution. Because radon is a naturally-occurring element, it's normal to have a small but measureable amount of radon in a building. Indoor radon levels are typically about 1.25 picoCuries per liter of air (1.25 pCi/L), but when levels are as high as 4 pCi/L it increases a person’s risk of lung cancer. The Surgeon General has identified radon as the second leading cause of lung cancer in the US today.
Radon is a radioactive gas released naturally, a decay product of uranium. A radon atom decays in less than 4 hours to polonium-218, which itself decays to thorium, and so on to the end product of very nonradioactive lead. If you breathe in a radon atom, it moves through its decay cycle fairly rapidly, leaving you with a lead atom in your lungs – not a pretty prospect. But it’s the sequence of alpha, beta, and gamma radiation that occurs in the brief time that causes the damage. (Tobacco smokers ingest polonium, and you know what happens to them!). The National Safety Council estimates that perhaps 14,000 deaths per year are caused by ingestion of radon.
Under normal circumstances, radon dissipates quickly in the atmosphere. But when radon enters buildings, through cracks in the foundation, loose pipes, or other openings, radon levels can build to potentially dangerous levels.
Not all homes have high radon levels. There are parts of the country that have higher or lower average levels, but the only way to be sure your home, school, or workplace has radon levels lower than the EPA action level of 4 pCi/L is to have the site tested. You can do it yourself, using test kits purchased from hardware stores, or order one online (check my list of links for a $10 kit offer).
Go To Page: 1
