So it's somewhat surprising to learn that bathroom door handles are not the dirtiest thing your hands usually touch. While this inexhaustive study didn't include a five-dollar crack whore's soiled underwear and the DVDs in the scheisse porn section of a German video store, the dirtiest thing most normal members of the population (in South Korea, at least, where this study took place) are shopping cart handles [1] -- with 1,100 colony-forming units of bacteria per 1.55 square inches.
According to Kwon Young-il, an official at The Korea Consumer Protection Board, this is because "the area is larger than the others and people have more space to place their hands."
Hmmm. Next on the list were computer mice in Internet cafes, which had an average of 690 colony-forming units of bacteria in the same area. Bus hand straps came in third, with 380 units, followed by bathroom doorknobs with 340.
I'm not sure I buy that line about the shopping cart handles having more bacteria because they are larger, because the bacteria per square centimeter was measured -- not the entire surface area of each object. My reasoning is that even the cleanest people don't wash their hands before shopping, using the computer, or riding the bus. While it is true that more people will attest to washing their hands after using the john than actually do, as evidenced in this rather old CNN study, [2] a majority of us do.
For people concerned about germs, this gives you new insight into when you should bust out the Purell. Stay away from shopping, public transportation, and internet cafes. After all, you don't know who's been clicking that mouse. It might have been that lower life form who didn't wash his hands after pooping.
