RADON (Rn)
The most common source of indoor radon is uranium in the soil or rock on which homes are built. As uranium naturally breaks down, it releases radon gas which is a colorless, odorless, radioactive gas. Radon gas enters homes through dirt floors, cracks in concrete walls and floors, floor drains, and sumps. When radon becomes trapped in buildings and concentrations build up indoors, exposure to radon becomes a concern.

Any home may have a radon problem. This means new and old homes, well-sealed and drafty homes, and homes with or without basements.

Sometimes radon enters the home through well water. In a small number of homes, the building materials can give off radon, too. However, building materials rarely cause radon problems by themselves.

Health Effects of Radon
The predominant health effect associated with exposure to elevated levels of radon is lung cancer. Research suggests that swallowing water with high radon levels may pose risks, too, although these are believed to be much lower than those from breathing air containing radon. Major health organizations (like the Centers for Disease Control and Prevention, the American Lung Association (ALA), and the American Medical Association) agree with estimates that radon causes thousands of preventable lung cancer deaths each year. EPA estimates that radon causes about 14,000 deaths per year in the United States--however, this number could range from 7,000 to 30,000 deaths per year. If you smoke and your home has high radon levels, your risk of lung cancer is especially high.

Reducing Exposure to Radon in Homes

• Measure levels of radon in your home. You can't see radon, but it's not hard to find out if you have a radon problem in your home. Testing is easy and should only take a little of your time. There are many kinds of inexpensive, do-it-yourself radon test kits you can get through the mail and in hardware stores and other retail outlets. EPA recommends that consumers use test kits that are state-certified or have met the requirements of some national radon proficiency program.
  
  
• Learn about radon reduction methods. Ways to reduce radon in your home are discussed in EPA's Consumer's Guide to Radon Reduction. You can get a copy from your state radon office. There are simple solutions to radon problems in homes. Thousands of homeowners have already fixed radon problems. Lowering high radon levels requires technical knowledge and special skills. You should use a contractor who is trained to fix radon problems.
  
  A trained radon reduction contractor can study the problem in your home and help you pick the correct treatment method. Check with your state radon office for names of qualified or state-certified radon-reduction contractors in your area.
  
  
• Stop smoking and discourage smoking in your home. Scientific evidence indicates that smoking combined with radon is an especially serious health risk. Stop smoking and lower your radon level to reduce lung cancer risk.
  
  
• Treat radon-contaminated well water. While radon in water is not a problem in homes served by most public water supplies, it has been found in well water. If you've tested the air in your home and found a radon problem, and you have a well, contact a lab certified to measure radiation in water to have your water tested. Radon problems in water can be readily fixed.