Radioactive decay From Wikipedia, the free encyclopedia ??(Redirected from Radioactivity) Jump to: navigation, search ? For particle decay in a more general context, see Particle decay. For more information on hazards of various kinds of radiation from decay, see Ionizing radiation. "Radioactive" redirects here. For other uses, see Radioactive (disambiguation). This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (April 2010)