"The best place to store your toothbrush is on the bathroom counter."
Your toothbrush could be carrying more than 1 million bacteria, including pathogens like streptococcus, staphylococcus and E. coli, especially if you haven't replaced it in four months. Dark, moist medicine cabinets and drawers with wrinkle cream residue provide the perfect conditions for these germs to thrive. But here's the problem with airing out your brush on the bathroom counter: Every time you flush with the cover up, you risk lightly contaminating everything nearby, explains O'Connor in his other fact-filled book, Never Shower in a Thunderstorm. A study in the journal Applied Microbiology showed that microscopic bacteria bombs that shoot into the air when you flush can land on surfaces throughout the bathroom.