Radon is a radioactive, colorless, odorless, tasteless noble gas occurring naturally as a decay product of radium.
Core Principles & Analysis
Friedrich Ernst Dorn identified radon in 1900 as the radioactive 'emanation' released by radium salts.
It is the densest noble gas, colorless and odorless, produced continuously by the decay of uranium and thorium in rocks and soil.
Radon seeping into basements is the second leading cause of lung cancer after smoking, driving widespread home testing, and its sealed seeds were once used in radiotherapy.