In the Spotlight


By Lawrence H. Flesh, MD

Radon is a gas that comes from the breakdown of naturally occurring uranium that is found in the ground, usually associated with granite. It can also be found in other rocks and in water. It occurs naturally in the earth, and can cause harm when it becomes concentrated indoors.

Radon has a number of different emissions of radioactivity, but the relatively large alpha particles are the ones that cause problems for people. Radon is the second leading cause for lung cancer second only to smoking, and to make matters worse, smokers are at a higher risk for developing Radon caused lung cancer. About 21,000 people die from Radon expose every year in the United States. Lung cancer occurs from 5-25 years after exposure, and the longer the exposure, or the greater the concentration of the gas in your house, the greater is the risk.

In your home, Radon exposure occurs in two ways. The Radon gas can come through the basement floor into the house, and collect in the air in the house. Radon can also be dissolved in well water, and get into the air when the water is run in your sink or tub. It is the gas the causes the problem. One breathes in the gas, and the Radon molecules get trapped in the lung tissue. There, the radioactive alpha particles cause tissue damage, and eventually a lung cancer develops.

The first step in correcting the problem is testing your house for Radon. Some areas of the country are known to have high Radon levels, such as parts of Upstate NY, and Southern Maine. Many states, and some banks, require that a home be tested for Radon before a mortgage is approved by the bank. Radon testing is easy and inexpensive. The EPA and each state where Radon levels can be significant provide information about Radon and testing.

Once Radon has been found to be present in a home, action has to be taken. The upper limits of acceptable levels are 2 pCi (picocuries) in the air, and 4000 pCi/L (picocuries per liter) in water in most states. Some states will allow slightly higher levels, but the lower the better for safety sake. If Radon is found in your home, it can be reduced (mediated) by licensed contractors. The process for Radon in the air is to put a pipe under the basement floor, and a fan in the piping that sucks out the air from under the slab, and vents it above the roof. For well water Radon, the water line is run into a special tank that bubbles air through the water, and then also vents it above the roof. Both techniques are very successful, and Radon levels can be reduced to an acceptable level.

More information is available from each state. Do a Google search under "Radon (Your State)" for example "Radon New York." This will point you to the state sites that give a wealth of information, a list of contractors, and sources for the test kits.

Learn More

Radon (Medline Plus)

Radón (Medline Plus) (en Español)

EPA Map of Radon Zones (PDF)

Updated/Reviewed: December 30, 2008