Your worst fear about your toothbrush is… true. Sorry, germophobes, but a new study presented at the annual meeting of the American Society for Microbiology confirmed that fecal matter is easily transmitted onto toothbrushes. The study collected toothbrushes used in communal bathrooms at Quinnipiac University in Hamden, Conn. At least 60 percent of the toothbrushes were contaminated with fecal coliforms. That’s a broad class of bacteria; while they don’t usually cause illness themselves, scientists use their presence as an indicator that other organisms—like viruses, protozoa, parasites or more dangerous bacteria—may also be present.
Microorganisms get onto toothbrushes when the toilet is flushed and miniscule droplets of water enter the air, or, when people aren’t properly washing their hands. But is an infinitesimal amount of poop on a toothbrush actually a problem? “The main concern is not with the presence of your own fecal matter on your toothbrush, but rather when a toothbrush is contaminated with fecal matter from someone else, which contains bacteria, viruses or parasites that are not part of your normal flora,” wrote Lauren Aber, a graduate student in health science at Quinnipiac University, in the study. According to the report, there is an 80 percent chance that the fecal coliforms seen on the toothbrushes came from another person using the same bathroom.
If you’re feeling a little grossed out, here’s how to keep your toothbrush cleaner:
- Counterintuitive as it may be, don’t cover the toothbrush with a cover or closed container. According to the American Dental Association, the moist environment inside a case is can help microorganisms grow faster.
- If you’re using a shared bathroom—on campus, in an office or if you’re sharing a house with a big group of people—don’t store your toothbrush in there. Take it back to your room.
- If you choose to use a toothbrush sanitizer, make sure any claims it makes has been FDA approved. Not all devices have research supporting their use.
- Rinse your mouth with an antimicrobial mouthwash prior to brushing.
- Don’t put toothbrushes into the microwave or dishwasher to sanitize them; manufacturers have not designed them to withstand that.
- Don’t share toothbrushes with anyone. Sounds like a no-brainer, but a lot of people will use their spouse’s brush.
- Store toothbrushes in an upright position, separated, and let them completely air dry between uses.
- Replace toothbrushes every three months.
Kathryn Drury Wagner is a writer and editor based in Los Angeles. Her latest book is Hawaii’s Strangest, Ickiest, Wildest Book Ever!