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Health Risks

Report: EPA's Assessment of Risks from Radon in Homes

In 2003 the Agency updated the estimates of lung cancer risks from indoor radon based on the National Academy of Sciences' (NAS) latest report on radon, the Biological Effects of Ionizing Radiation (BEIR) VI Report (1999). EPA worked closely with the Science Advisory Board (SAB), an independent panel of scientific experts, to determine how best to apply the risk models developed by the BEIR VI committee. The SAB's advice and recommendations were incorporated modifying and extending the methods and approaches used in BEIR VI to construct a single model yielding results midway between the results obtained using the two models preferred by the BEIR VI committee. The Agency's updated calculation of a best estimate of annual lung cancer deaths from radon is about 21,000 (with an uncertainty range of 8,000 to 45,000), which is consistent with the estimates of the BEIR VI Report. A single risk model also permitted the Agency to calculate a numerical estimate of the risk per unit exposure [lung cancer deaths per working level month (WLM)] which will be used to update estimated lung cancer risks from radon in various publications, including A Citizen's Guide to Radon.

The following is an updated chart of the lifetime risk of lung cancer death per person from radon exposure in homes (excerpted from the updated radon risk assessment).

Radon Levela Lifetime Risk of Lung Cancer Death (per person) from Radon Exposure in Homes b
pCi/L Never Smokers Current Smokers c General Population
20 36 out of 1,000 26 out of 100 11 out of 100
10 18 out of 1,000 15 out of 100 56 out of 1,000
8 15 out of 1,000 12 out of 100 45 out of 1,000
4 73 out of 10,000 62 out of 1,000 23 out of 1,000
2 37 out of 10,000 32 out of 1,000 12 out of 1,000
1.25 23 out of 10,000 20 out of 1,000 73 out of 10,000
0.4 73 out of 100,000 64 out of 10,000 23 out of 10,000
a Assumes constant lifetime exposure in homes at these levels.
b Estimates are subject to uncertainties as discussed in Chapter VIII of the risk assessment.
c Note: BEIR VI did not specify excess relative risks for current smokers.

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Biological Effects of Ionizing Radiation (BEIR) VI Report: "The Health Effects of Exposure to Indoor Radon"

BEIR VI Book cover

The National Research Council published the report, entitled: "Health Effects of Exposure to Radon: BEIR VI, Committee on Health Risks of Exposure to Radon (BEIR VI)". This report by the National Academy of Sciences (NAS) is the most definitive accumulation of scientific data on indoor radon. The report confirms that radon is the second leading cause of lung cancer in the U.S. and that it is a serious public health problem. The study fully supports EPA estimates that radon causes about 15,000 lung cancer deaths per year.

The ISBN number for the book is 0-309-056454-4; National Academy Press, 516 pages, 1999. The listed hardcover price for the book is $54.95 U.S. and $66.00 Intl. The Report can be read and purchased from The National Academies Press Read the Executive Summary and the Public Summary at http://books.nap.edu/html/beir6/

Test Your Home for Radon, It's Easy and Inexpensive

The U.S. Surgeon General and EPA recommend that all homes be tested.  Read about radon health risks.

Fix your home if you have a radon level of 4 pCi/L or more.
You can test your home yourself or hire a professional. Find a service professional near you.

If you have further questions about Radon, please call your State Radon Contact.

Download this recently revised customizable fact sheet!
(PDF, 2 pp, 150 K)
EPA 402/F-12/005, February 2013

Federal Radon Action Plan Health Risks Hotlines & Resources Test or Fix Your Home Kids, Students and Teachers Map of Radon Zones Media Campaigns National Radon Action Month Radon-Resistant New Construction Radon and Real Estate Radon in Drinking Water Radon Leaders Saving Lives State Radon Contacts State Indoor Radon Grants Indoor airPLUS Indoor Air Quality

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