Radon Gas

Radon (chemical symbol Rn) has numerous different isotopes; but Radon-222 is the primary and most common isotope of radon, which is of public health interest.

Radon-222 is a colorless, odorless, tasteless and inert gas produced by the natural (radioactive) decay/breakdown of Radium-226 (itself a decay of Uranium-238) in soil, rock and water. Radon gets into the air you breathe. It can get into any type of building - homes, offices, schools, etc. - and build up to high levels. Consequently, radon is the largest source of exposure to naturally occurring radiation.

However, the primary risk of lung cancer from exposure to Radon-222 does not come from direct exposure to the gas itself, but from exposure to the Radon Decay Products (RDP), which are solid, airborne and breathable particles. The most dangerous RDP are the alpha ray emitters Polonium-218 and Polonium-214, which account for the major portion of radiation doses received in most situations and are the primary source of radon-induced lung cancers.

You and your family are most likely to get your highest exposure at home, because Radon-222 tends to collect in homes, sometimes to very high concentrations, and since that is where you spend most of your time.