Understanding the Radon Danger

Radon is a gaseous radioactive element having the symbol Rn with the atomic number 86. It is an extremely toxic colorless gas and is derived from the radioactive decay of radium and uranium which occurs naturally in soil and rock. Radon levels, therefore, can vary from home to home.

How does radon get into homes? Radon is a radioactive gas. It comes from the natural decay of uranium that is found in nearly all soils. It typically moves up through the ground to the air above and into homes through cracks and other holes in the foundation. The home traps radon inside, where it can build up. Any home may have a radon problem.

Exposure to Radon has no immediate symptoms. There is no debate about Radon being a lung carcinogen in humans. All major national and international organizations that have examined the health risks of radon agree that it is a lung carcinogen. The National Academy of Sciences BEIR VI Report has estimated that radon causes about 15,000 to 22,000 lung cancer deaths annually.

The World Health Organization, the National Academy of Sciences, the US Department of Health and Human Services, as well as, the EPA have classified radon as a known human carcinogen because of the wealth of biological and epidemiological evidence and data showing the connection between exposure to radon and lung cancer in humans. All of these organizations believe that approximately 12% of lung cancers annually in the United States are attributable to radon.

“We already have a wealth of scientific data on the relationship between radon exposure and the development of lung cancer. The scientific experts agree that the occupational miner data is a very solid base from which to estimate risk of lung cancer deaths annually. While residential radon epidemiology studies will improve what we know about radon, they will not supersede the occupational data. Health authorities like the Centers for Disease Control, the Surgeon General, the American Lung Association, the American Medical Association, and others agree that we know enough now to recommend radon testing and to encourage public action when levels are above 4 pCi/L. The most comprehensive of these efforts has been the National Academy of Science’s Biological Effects of Ionizing Radiation (BEIR VI) Report. This report reinforces that radon is the second-leading cause of lung cancer and is a serious public health problem.

Radon can be a problem in all types of homes, including old homes, new homes, drafty homes, insulated homes, homes with basements and homes without basements. Testing homes for radon is the only way to know if radon levels are dangerously high. The only way to know whether radon exists in elevated levels is to TEST. The EPA has rated every county in the United States on the level of radon in each county. See map on the next page.
 

EPA Map of Radon Zones

The purpose of this map is to assist National, State, and local organizations to target their resources and to implement radon-resistant building codes. This map is not intended to be used to determine if a home in a given zone should be tested for radon. Homes with elevated levels of radon have been found in all three zones. All homes should be tested regardless of geographic location.  Important points to note:

·         All homes should test for radon, regardless of geographic location or zone designation

·         There are many thousands of individual homes with elevated radon levels in Zone 2 and 3.  Elevated levels can be found in Zone 2 and Zone 3 counties.

·         All users of the map should carefully review the map documentation for information on within-county variations in radon potential and supplement the map with locally available information before making any decisions.

·         The map is not to be used in lieu of testing during real estate transactions.
 

•     Zone 1 counties have a predicted average indoor radon screening level greater than 4 pCi/L (pico curies per liter) (red zones)

• Zone 2 counties have a predicted average indoor radon screening level between 2 and 4 pCi/L (orange zones)

•     Zone 3 counties have a predicted average indoor radon screening level less than 2 pCi/L (yellow zones)