Some words just don't belong together. Oxymorons collapse under scrutiny: "Good problem." "Happy accident." "Public restroom."
The last combo concerns us here. It might concern, you, too, in the sense that public restrooms cause some of us a low-level but constant sense of worry. The whole point of a restroom is that it's private—the unspeakable stage on which the ancient dramas of expulsion, shame, and concealment play out—Greek tragedy by way of Freud.
What's rightfully public? Public libraries. Public decency. Public health. All good things. We support these things. Public restrooms, no thanks.
And yet shared toilets remain a reality of daily life for many, if not most, Americans, despite the dissonance between communal availability and the thoroughly private activities we perform upon and within them (and sometimes, to judge by our office bathroom, near them).
This must be why we're so ready to believe that these facilities pose grave threats to our health and safety. Admit it: Some part of you, large or small, suspects that the gas station bathroom would rather see you sick or injured than accept more than one flush from a stranger.
Chris Makley, owner of a green cleaning company based in Rochester, New York, puts the issue more bluntly.
"Just assume [public restrooms] are actively trying to kill you," Makley says.
Wait, though, because these fears are probably a bit overblown. Or a lot. Are there germs in public restrooms? Boy howdy, are there ever. Are they all pathogens that will eat our flesh and destroy our fertility and cover us with leprotic lesions, writing our secret shame all over our oozing faces? Not exactly.
"For the most part ... our immune systems can handle it," Makley admits. Microbial ecologist Jack Gilbert essentially shrugs his shoulders at the notion of the disease-riddled bathroom. Potentially dangerous germs are already all over us, Gilbert told NPR. We just need to keep the ratios healthy.
"All human environments contain pathogens—your bedroom, the phone you're talking on, even the bugs inside of you could turn pathogenic at any time," Gilbert said. "But we desperately need them in our lives."
So with that caveat in mind, let's take a tour of the standard public restroom, pausing to consider the threat—and the purpose—of every stop along the way.
1. The Door Handle
The journey to Germville starts at the door. Luckily, door handles aren't so bad, relatively speaking. The pioneering work on a microbial map of the public restroom is a 2011 study titled, poetically, Microbial Biogeography of Public Restroom Surfaces. A group of researchers stalked the restrooms of the University of Colorado at Boulder with cotton swabs and a mission. They tested various surfaces, including door handles, for microbial life.
Perhaps unsurprisingly, surfaces that users touch with their hands a lot—door handles chief among them—were littered with bacteria that naturally live on human skin. Common, mostly harmless bacteria from the family Propionibacteriaceae dominate door handles, the researchers found. So far so good.
Of course, bathroom door handles in the study also harbored a smattering of bacteria associated with the human mouth and with urine. So "good" is a relative quality here. The point is, touching a bathroom door handle does not create a huge risk of illness, at least not generally. The question to ask yourself at this point is: "How badly do I need to get into that room?"
2. The Toilet
Here we are: Bacterial ground zero. We're skipping over urinals for now, since they exclude half the population. Besides, the real gnarly stuff rests with the sit-down toilet...because the real gnarly stuff is fecal in origin. Let's let the scientists talk the science:
"Toilet flush handles and seats … were relatively enriched in Firmicutes … and Bacteroidetes," the authors of Microbial Biogeography of Public Restroom Surfaces wrote.
"These taxa are generally associated with the human gut suggesting fecal contamination of these surfaces."
Oh. Yuck. But it makes sense. Anyone who's heard about the "toilet plume" can tell you how this contamination spreads.
"Most people don't close the commode lid and that mist can reach every area of the bathroom," explains Makley. "You basically have a coating of urine [and] feces juice on everything."
Awful but true. A recent literature review on toilet aerosols—in which microscopic particles of whatever's in the bowl spray everywhere, like a whale spouting, but way grosser, when you press the lever—found that, sure enough, "potentially infectious aerosols may be produced in substantial quantities during flushing."
However, that literature review also notes that no research has uncovered a verified case of a disease caused by The Plume of Doom. That doesn't mean we should just shrug and accept the "fine patina of feces" that covers the world, as microbiologist Stanley Falkow quotably described it to writer Michael Pollan.
Poo germs are nothing to sneeze at, it turns out. According to the New York Times, other bathroom-swabbers have picked up E. coli, streptococcus, and norovirus, nicknamed the "cruise ship bug" with stomach-turning accuracy. Don't worry too much, though; your skin will keep out these pathogens, so unless you rub an open wound or your tongue on the toilet seat, you should remain uninfected.
We're just saying that it's sick to think about.
3. The Sink
Finally! An oasis of cleanliness. Except that it isn't. Remember The Plume.
Consider a 2014 study called Ecological succession and viability of human-associated microbiota on restroom surfaces, which we'd translate as Germs From Inside Humans Are All Over Bathrooms All The Time.
Even the soap dispensers were covered in bacteria, these researchers found. Forty-five percent of that bacteria had its origin in the human gut, and specifically in the human gut's final product.
Antimicrobial product manufacturer BioCote conducted their own study. It found the sink to harbor the most bacteria in the restroom, far more than even the toilet seat. Sure, BioCote has a product to sell. They're hardly neutral third parties. Still, it's hard to doubt BioCote Technical Director Richard Hastings' quote in the press release:
"In many cases, germs are spread via touch, so we can see that objects touched after people have used the toilet, but before they have washed their hands, can be just as contaminated [as the toilet seat,"] Hastings said.
But don't let that stop you from washing your hands. The Centers for Disease Control and Prevention (CDC) still recommend washing your hands with soap and clean running water directly upon completing your toilet obligations. They also say you should scrub for at least 20 seconds. Don't forget between your fingers, under your nails, and the backs of your hands. The CDC is serious about hand-washing.
4. The Hand Dryer
Once you get your hands clean, though, consider reaching for the paper towels. We're sorry to the trees, but the only research we know that compares bacterial growth on hands after air- or paper-drying shows a clear favorite.
"From a hygiene viewpoint, paper towels are superior to electric air dryers," claims a 2012 literature review published in the journal Mayo Clinic Proceedings.
In the review, researchers found that hot air dryers actually increase the number of bacteria on the subject's hands following a wash in the sink. Jet air dryers also boosted the bacteria count, though not as much as the hot air variety. Just one technique actually reduced bacteria on the washed hands, and that was...you guessed it...paper towels.
Makley points out a possibility that makes the notion of electric hand dryers even worse.
"You may as well assume that any fan or heating vent is shooting mold and mildew spores," he says. "Hot, wet conditions make it ripe and NO ONE, not even professional house cleaners, [hits] those two things regularly."
That's his emphasis, to be clear. His emphasis all the way.
5. The Way Out
We're almost clear. Our guts are clear, hands washed, crumpled, wet paper towels stacked precariously on the over-full trash can. There's just one obstacle left: The inner door.
This one is much worse than the outer door. That's not just your imagination. According to Microbial Biogeography…(you know the rest), the door that exits the bathroom has a slightly higher proportion of bacteria associated with urine than the door in. Inexplicably, it also has more bacteria associated with the mouth.
If this all proves too much for you, don't despair.
Technology will save us some day. First off, two teenagers in Hong Kong invented a bathroom door handle that shines UV light through a titanium dioxide shaft, essentially rendering it antibacterial.
And if that doesn't work, someone built a real-life version of the Fremen stillsuit from Frank Herbert's Dune—or, if you prefer, David Lynch's maligned film adaptation of Dune, which is actually better than any of the original Star Wars films, but we digress.
Anyway, stillsuits collect sweat and excreta and convert them into drinkable water. They're wearable and fashionable. And there are no public restrooms on the desert planet.
The real-life version of the stillsuit technology is only working with sweat so far. We'll have to wait for the rest of the equation. But someday, not too long from now, we could all sit in our office chairs, working diligently, and relieving ourselves in perfect privacy...if not comfort.
Until that day arrives, remember Makley's final words of advice:
When you use your home bathroom, put down the seat before flushing. And in public restrooms?
"Pray to the ancient gods," Makley says. "And don't open doors with your hands. Ever."