How Radioactive (In Bananas) is the Room You're Sitting in Right Now?

According to recent research (and some of my own calculations) sitting in your living room for an hour yields roughly the same dose of radiation as eating half a banana. A team in China working on improving the way scientists measure a room's radioactivity calculated how much radiation an average room gives off. Everything emits a trace amount of radiation. Bananas, dirt, seagulls, Abe Vigoda and coffee tables are all to some degree a very tiny bit radioactive. It's because radioactive element...