Public health organizations – and our moms - have drilled into us for years the importance of washing our hands to prevent the spread of disease, especially after using the restroom. But it turns out, how you dry your hands after washing might mean the difference between clean hands, or hands you might as well have washed in the toilet.
Public restrooms are inherently nasty places. Most people avoid them if they can. But, when nature calls, you got to go! To mitigate your exposure to whatever is lurking in there, you, I'm sure, wash your hands afterward. That's a good thing! Did I mention restrooms are a festering frat-party of microscopic ner-do-wells – bacteria, viruses, and germs - whose names start with scary-sounding prefixes like strep, hep and staph. Not to mention E.coli, cold and flu bugs.
Now, imagine all of those being blown right back onto your freshly washed hands!
A recent study by researchers at the University of Connecticut and published in the journal Applied and Environmental Microbiology, reveals those powerful warm-air hand drying machines suck up whatever is in the air and then blow it back out in a concentrated current that lands on – your clean hands! The study concludes, "Many kinds of bacteria, including potential pathogens and spores, can be deposited on hands exposed to bathroom hand dryers..."
We showed the study to microbiologist Carter Wright. She studies disease-causing germs at Gene Capture at the HudsonAlpha Institute for Biotechnology. "We wash our hands to get rid of this bacteria, and yet we're just blowing it right back on them," she said. "I don't think the study is meant to make us paranoid but is meant to educate people to be aware."
Still, it's hard not to cringe at the results. The study found up to 60 colonies of bacteria were blown out of hand dryers in a 30 second cycle. The study mentioned staphylococcus aureus. That's the "SA" part of the acronym MRSA, a staph bacterium that is resistant to antibiotics. "Staph aureus is one that was found in the study. And staph aureus can be a very serious infection," warns Wright.
According to Wright, no matter how careful you are in the bathroom these germs are impossible to avoid. "Every time a toilet is flushed, that bacteria are being dispersed into the air," she said.
The argument is, when you flush the toilet, some of that toilet water is aerosolized, meaning whatever you do in the stall spreads to the rest of the bathroom. That's right, microscopic fecal matter is floating all around you. To be clear, hand dryers do not add bacteria to the restroom. They simply re-circulate what's already there. And studies show they make things worse by blowing the bugs around the room. The University of Leeds in England found "bacteria levels in the air around hand dryers were 27 times higher than around paper towel dispensers."
And there-in lies the answer.
"I always say, if you're able to use paper towels, that's the way to go," said Wright. In fact, the microbiologist goes to great lengths to avoid a hand dryer. "If I didn't have paper towels, honestly, I'd probably just use my pants."
Wright said hand sanitizer, which some restrooms thoughtfully supply, is also a good way to avoid using a hand dryer. "If you don't have paper towels, it's a good backup. That way you're not having to put your hands under those dryers that are putting those bacteria back onto them," she said.
The hand dryer industry sites studies of its own that show bacteria are everywhere, even on paper towels. They also say hand dryers are more cost effective, especially for high-volume restrooms. They last five to seven years, with very little maintenance. There's no waste management. No replacing costly paper towels. No angry customers when the facility runs out of paper towels. Not to mention a cleaner environment.
It makes sound business sense. But if it's your business to stay healthy, according to the experts, paper towels have the edge. A 2012 Mayo Clinic review of a dozen studies on the subject concluded "From a hygiene viewpoint, paper towels are superior to electric air dryers."
The U-Conn study found that dryers with HEPA filters significantly reduced the number of bacteria coming out, but not all dryers have them. And keep in mind, public restrooms are probably not the dirtiest thing you encountered today. Scientists say your cell phone and the restaurant menu you picked up are loaded with a lot more germs.
Unless you have a compromised immune system or an open wound, your body can likely deal with a few bathroom bacteria. Wright says the most important thing is to wash your hands, no matter how you dry them. But consider how they dry their hands in a facility like hers.
"You will not find anything but paper towels."