April 9, 2012: What is Radon and why does it matter to human health?

Radon (222Rn) is an element, formed as the sixth element in the radiation decay sequence of uranium (238U).  It is odorless, colorless and radioactive.  Radon itself is not toxic because of its chemical or radiological characteristics!  So why worry?  Radon continues to decay into several progeny, frequently called “daughter products”; its half-life is about 3.8 days.  The progeny, polonium (218Po and 210Po) and lead (214Pb) however emit alpha radiation (helium nuclei) which is toxic to the lung causing increases in small cell and squamous cell carcinomas.  The CDC estimates that it is the second leading cause of lung cancer in the US.  The EPA and Surgeon General’s office estimate more than 20,000 lung cancer deaths each year are attributable to radon.

Testing homes for radon helps identify homes where radon collects.  Since radon comes from the ground it will seep and accumulate into enclosed areas such as basements, buildings, and mines.  Radon enters the home through cracks in solid floors and walls, construction joints, gaps in service pipes, cavities in walls, and the water supply.  Test kits can be bought that will measure the amount of radon in a home.  There are also qualified testers that can come to your home and measure for you.  If radon levels are elevated in the home (>4pCi/L), then sealing cracks and joints and possibly installing a radon vent pipe system are indicated.  Consult with a qualified or state certified radon contractor.  Many states are now requiring radon tests prior to sale of homes.


This question prepared by:  John Benitez, MD, MPH  Medical Toxicologist


I am interested in any questions you would like answered in the Question of the Week.  Please email me with any suggestion at donna.seger@vanderbilt.edu


Donna Seger, MD

Medical Director

Tennessee Poison Center

Website: www.tnpoisoncenter.org

Poison Help Hotline: 1-800-222-1222