It is colorless, odorless, and tasteless. When a person breathes radon, they increase their chances of getting lung cancer. In fact, the U.S. Surgeon General has warned that radon is the second leading cause of lung cancer in the U.S. today.
Radon comes from rocks, soil, and well water that contains uranium and radium.
Radon is found throughout the United States, and is particularly prevalent in Colorado. The U.S. EPA has ranked Colorado as a Zone 1 area, which means that the average house will probably exceed the EPA's action level for indoor radon. Testing for radon is easy and inexpensive. Radon is produced as a decay product from uranium and radium. This naturally occurring radioactive gas is found in most soil and rock, and in most ground water.