Chances are you’ve heard about the infamous toilet plume. One piece of advice to minimize the plume that gets thrown around is to close the toilet lid before you flush. But does it really make a difference? And what else should we be doing to have some peace of mind germ-wise when we use the bathroom? We talked to a couple of microbiology experts to get the (kind of gross, tbh) truth.
Flushing the toilet does, in fact, spray poop particles into the air.
First things first: Poop particles are all around us, according to Paul Pottinger, M.D., professor of medicine and codirector of the Antimicrobial Stewardship Program at the University of Washington Medical Center.
When you flush a toilet, the power of the flush aerosolizes whatever particles are in the bowl, says Kelly Reynolds, Ph.D., M.S.P.H., professor and director of the Environment, Exposure Science and Risk Assessment Center at the University of Arizona. “Aerosols can disperse anywhere from one to six feet; three feet is the average,” she tells SELF. That means that microscopic organisms from your poop, pee, and whatever else is in your toilet have a chance to spread out across your bathroom.
“The world is covered in stool, the only question is how [much],” Dr. Pottinger says. So, sorry to break it to you, but if you live with other people and share a bathroom with them, then...yep, you guessed it. “Believe it or not, there is a great chance that housemates are already covered with a fine fecal patina from one another. Sounds gross, but the truth is we are all covered in germs. They are usually quite harmless and often beneficial.”
Toilet plume usually isn’t a big deal—unless someone using the toilet is sick.
Okay, so, toilet plume sounds gross, but how worried should you be about it in terms of your health? Experts say it really depends on a few different specifics. “We all have different susceptibilities to getting an infection when exposed to microbes,” Dr. Reynolds says. “Some people never get sick, some get sick all the time, and some of that is hard to explain.”
Relatively speaking, though, the overall risk of getting sick because of microbes that spread during a toilet flush is low, Dr. Reynolds says. “We find that bathrooms have a much lower risk of exposure to pathogens than our own kitchen,” she says. (That’s a story for another day.)
The biggest toilet plume risk happens when someone using the toilet is actually ill with a contagious illness. “Diarrhea is usually caused by a bacteria or virus that infects the digestive system. When it’s expelled in a bowel movement, it can end up on a surface that a second person touches and then touches their mouth,” Dr. Pottinger explains. So, the bugs that are in your average run-of-the-mill feces aren’t likely to make you sick, especially since you’re already sharing those microbes with whomever you live with. It’s the illness-causing bugs that are more concerning. (Yes, possibly including the SARS-CoV-2 virus that causes COVID-19.) And the reality is that we don’t always know when someone is sick, Dr. Reynolds says, explaining, “You don’t have to be symptomatic to be shedding organisms that can make people sick.”
