I learned that the detectors that check for explosives look for a compound called ammonium nitrate, which can sometimes be found in creams and lotions. This is not meant to scare people to never wear lotion again. But, in this story the woman probably put some on while she was in line before going through the detectors. I always put lotion on in the morning before I leave my house, so by the time I get to the airport I should be fine, but you could always just wash your hands before going through security.
