60,000 people a day undergo some type of treatment or test that leaves small amounts of radioactive material in their bodies. If any of those folks happen to be part of the packed house at Dolphin Stadium this Sunday, they may have to explain to security officials why they're radioactive enough to set off "dirty bomb" alarms.

In the wake of the September 11th attacks, the U.S. Department of Homeland Security issued over 12,000 hand-held radiation detectors for use at airports, border crossings, government buildings and large public events like the Superbowl. The people police pull aside may not be terrorists, however, but merely patients who've recently had medical treatments with radioisotopes in their bodies. That's what happened to six members of the crowd at New York City's tree-lighting party last November -- a mistake that, according to Richard Falkenrath, the city's deputy commissioner of counter-terrorism, "happens all the time."

There have been some embarrassing mistakes, but generally such cases are resolved after police use a more sophisticated device to detect the type of radiation present. That being said, if you're someone who's undergone this type of treatment, especially if you'll be at the game on Sunday, you might want to carry a note from your doctor.