Radioactive material has been stolen off a truck in the southern Mexican state of Tabasco, and Mexico has put four neighboring states and federal agencies on alert as it seeks to recover the iridium-192, which CBS News reports is capable of causing serious lesions and death within a day if it escapes its protective casing. The IAEA classifies iridium-192 as a Category 2 substance; it has medical applications and was in a secure container. Officials urge anyone who finds it to establish a perimeter at least 90 feet away and not attempt to handle it.
The incident is at least the second such theft in recent years, though cobalt-60 that went missing in late 2013 turned out to be accidentally grabbed by thieves who didn't know what they'd taken; several people were later treated for radiation exposure. (Read more Mexico stories.)