radon(redirected from thoron)
Also found in: Dictionary, Thesaurus, Medical, Acronyms, Encyclopedia, Wikipedia.
Related to thoron: radon, thorium
Colorless, odorless gas that occurs naturally due to the breakdown of minerals in the earth. It tends to become trapped in our modern, nearly air-tight homes. Since there has been some correlation between radon and lung cancer, the EPA recommends levels no higher than 4 picocuries per liter (pCi/L), although generally acceptable levels are in the range of 4 to 8 pCi/L. The EPA Web site at www.epa.gov has information on testing for radon and reducing it.