This National Research Council's report of the sixth Committee on Biological Effects of Ionizing Radiations (BEIR VI) addresses the risk of associated with exposure to radon and its radioactive progeny. Radon, a naturally occurring gas formed from the decay of uranium in the earth, has been conclusively shown in epidemiologic studies of underground miners to cause lung-cancer. There is supporting evidence from experimental studies of animals that confirm radon as a cause of lung-cancer and from molecular and cellular studies that provide an understanding of the mechanisms by which radon causes lung-cancer.
In addition to being present at high concentrations in many types of underground mines, radon is found in homes and is also present outdoors. Extensive measurements of radon concentrations in homes show that although concentrations vary widely, radon is universally present, raising concerns that radon in homes increases lung-cancer risk for the general population, especially those who spend a majority of their time indoors at home. For the purpose of developing public policy to manage the risk associated with indoor radon, there is a need to characterize the possible risks across the range of exposures received by the population. The higher end of that range of exposures is comparable to those exposures that caused lung-cancer in underground miners. The lower end of that range includes exposures received from an average indoor lifetime exposure which is at least one order of magnitude lower.
Risk models, which mathematically represent the relationship between exposure and risk, have been developed and used to assess the lung-cancer risks