You know what happens when your nuclear reactor explodes, sending radioactive materials into the dirt? The irradiated gunk gets into the plants. Animals eat the plants. Humans eat the animals. You can see where this is going. Japanese health officials have found radioactive cesium in packaged beef, CNN reports—beef that in all likelihood's been eaten by now. The source of the contamination lies in hay from the agrarian Fukushima Prefecture, and the Japanese government doesn't yet have a handle on how widespread the tainted meat has become. They are, of course, downplaying the danger of the radioactive meat, despite the fact that cesium isotopes are among some of the worst to ingest. Luckily, a bolstered screening process will be implemented on Japanese farms, replacing the previous (and highly superficial) self regulation. [CNN, Photo: Chris McGrath/Getty]