The song, along with its accompanying music video, premiered on September 8 on the Kings' website. The following day, it received its official radio premiere on Australian radio, and debuted on US Alternative Radio on September 13. The song was released on US iTunes on September 14, and released at a later date in remaining countries.

The song was nominated for the 53rd Grammy Awards in two categories: Best Rock Performance by a Duo or Group with Vocals and Best Rock Song. The song is used in the films I Am Number Four and Boyhood.

The music video was released on September 8, 2010 on the Kings of Leon's website. The video that was made in a sepia-tone refers to the band's southern origins. It shows the band at a barbecue with a Gospel children's choir. Drummer Nathan Followill said, "Gospel music was a big part of us growing up, so to be able to come back and revisit that part of our lives at this stage in our lives is a pretty special thing."

NME named Radioactive's music video the second worst music video ever, commenting, "The music industry gasped in disbelief as the Oklahoma boys leapt into a muddled mise-en-scene of questionable racial subtext."

Kings of Leon performed the song on Saturday Night Live on October 23, 2010 and on Late Show with David Letterman on October 25, 2010. On November 25, 2010, the band gave a mini-concert in New York for The Today Show during which they performed a three-song set including "Radioactive". They also sang it on May 13, 2011 on VH1 Storytellers.

"Radioactive" debuted and peaked at #37 on the Billboard Hot 100. It has since re-entered the chart at number 65 upon the release of the album.

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Wikipedia