Some poor beleaguered souls working at a 7-Eleven in Oregon were just trying to serve up some Big Gulps and hot dogs when their microwave suddenly exploded. They called the cops, and when the proper authorities checked out the situation, they didn't find a bomb. Instead, they say it contained a urine sample.
According to local Beaverton, Oregon news station KATU, the cops evacuated the convenience store and brought in the explosives unit. After careful inspection, they determined that a urine sample had been wrapped in a handwarmer and was being heated in the microwave by someone who'd fled the scene.
While Oregon is one of the few places where recreational cannabis use is legal, it's still legal for employers and the government to drug test people. (Yes, drug tests cover other substances too, but it's a notable fact. Potheads love 7-Eleven.) Police believe the person they are looking for was on their way to a drug test and popped into the store to heat up a sample of clean urine. "It appears that whoever was on his/her way to do a drug test did not feel that it was warm enough, so they decided to microwave it at 7-Eleven," Mike Rowe, a police spokesperson, said in an official release. "The chemical makeup of the hand warmer did not agree with the microwave and exploded."
Indeed, microwaves and handwarmers aren't a good mix. Most people know that some aluminium foil can kill your microwave, but that principle applies to most metals. The fabric pouch of a handwarmer contains iron powder, activated charcoal, sodium chloride and vermiculite. Basically, a handwarmer heats up through a chemical reaction that causes oxidation of the iron.
Microwave ovens use microwave radiation to vibrate the molecules in food, eventually cooking it. But microwave radiation doesn't penetrate metal, it simply gets reflected. This can cause fires (like say, a flaming fabric pouch), sparks can punch holes in the lining of the microwave, and it can blow the magnetron that makes the microwave oven do its thing. We don't know exactly what happened to this particular, urine-soaked microwave, but it wouldn't be surprising if everything went wrong that could go wrong.
Police plan to check the security cameras to find their suspect. That person better hope they weren't scheduled for a drug test by the US government, because that would really narrow down the list of potential perpetrators.