How Radon Causes Lung Cancer

Radon is the second leading cause of lung cancer; it is the number one cause of lung cancer among non-smokers. Each year, radon kills thousands of Americans, and is responsible for 15% of lung cancers worldwide. Since lung cancer has the lowest survival rate of all cancers, it's important to know what radon is, how it causes lung cancer, and what we need to do to prevent exposure to radon.

What is Radon?

Radon is an invisible, odorless, tasteless gas. It is considered to be "complete carcinogen" and is classified as a "Class A" carcinogen because it can act solely to initiate, promote and propagate cancer.

Why Is Radon Lethal?

Radon becomes destructive when it undergoes radioactive decay. When radon decays, radiation and radon progeny (daughters) are produced. These radon progeny are composed of heavy metal particles of lead, polonium, and bismuth that are electrically charged. They are so minute that they become airborne, traveling through the air where they are inhaled.

How Radon Enters the Lungs

Some radon particles enter the lungs alone, while others "ride" on dust or smoke particles. Although all radon particles enter the lungs, it is the radon particles that travel alone that get lodged the deepest in the lungs. This is because radon particles are much smaller than dust or smoke particles; therefore, they can travel further within the lungs before becoming lodged. (See: How Particles Get Into the Lungs & Air Passages)

How Radon Invades the Lungs

Some radon particles penetrate only millimeters into the epithelial cells that line the interior of the lungs. Because some radon particles can not travel any further, they become concentrated and cause severe damage to the lungs. Concentrated radon particles are responsible for over 85% of the damage caused to the lungs.

Other more active radon particles travel deeper into the body's tissues; therefore, they are less concentrated and less harmful. Whilst other radon particles are so energetic that they pass completely through the body. These radon particles are the least damaging since they do not become lodged within the body.

How Radon Damages the Lungs

Large concentrations of radon are not necessary to cause lung cancer. A single radon atom alone can cause lung cancer. Radon particles damage cells by altering their genetic material. The damage typically kills or disables cellular reproduction. However, in some cases, the damaged cell may survive and continue to reproduce in a mutated state, forming cancerous tumors.

Sources: epa.gov and radonseal.com
Published: 12/12/05