Add Yahoo as a preferred source to see more of our stories on Google. The promotion was real — for 15 cents and a Kix cereal box top, one could receive a ring containing polonium-210, the same deadly ...

Cereal prizes used to be a big deal. In the 1940s and 1950s, kids didn’t just eat breakfast; they studied the box, filled out mail-in forms, and waited weeks for something exciting to arrive.