For many people, the cardinal rule of behavior regarding the use of public restrooms is: avoid them at all costs. Recent surveys suggest 65-70 percent of Americans will not use public facilities unless it is an absolute necessity.
“Basically, everybody is fearful of public restrooms,” Lisa Bernstein, MD, of Emory University said. Her colleague, Charles Gerba, PhD, of the University of Arizona, agreed: “Using a public restroom can be like playing Russian Roulette.”
Microbiologists recognize restrooms are shared public spaces that clearly have “disease transmitting potential.”
Every surface in the washroom is liable to contain a celebration of microbial diversity. Writing in The New York Times, Alice Callahan noted that restrooms in workplaces, classrooms, cruise ships, and airplanes have all evidenced pathogens like salmonella, Hepatitis A, and norovirus. These disease-causing organisms were not only present on toilets, but virtually all surfaces in the immediate vicinity.
Because most lavatories are small, unventilated, and feature running water, they are magnets for germs. Researchers have actually identified in them thousands of microorganisms, including streptococcus, staphylococcus, and E. Coli. As molecular biologist Ali Nouri, PhD, dryly put it, “You don’t want to sit down and read the comics in a public bathroom.”
The leading culprit for the dissemination of pathogens is the toilet. Scientists have known about toilet plumes for decades — the plume is a dispersal of microscopic particles which are launched into the air when a toilet is flushed. These droplets have the potential to contaminate everything on which they land.
Dr. Gerba — lovingly referred to as “Dr. Germ” — captured the attention of the microbiological community in 1975 when he published a paper that stated it is possible to catch an infection from toilet aerosols. Dr. Gerba’s assertion has been much debated since then, but many believe he is correct.
Subsequently, it has also been hypothesized that urinals produce harmful plumes.
Dr. Gerba first became interested in toilet plumes when he was in graduate school studying water bearing viruses. His advisor suggested paying attention to the spray generated by a toilet flush: it was a revelatory discovery. Dr. Gerba developed instruments which tracked the patterns of the aerosol, including a strobe light device that allowed him to photograph the plume.
According to Dr. Gerba, restroom floors are the most contaminated surfaces, even more than toilet seats or stall door handles. Floors can have more than two million bacteria per square inch — not the best place to put a purse, suitcase, or briefcase.
Sinks, because they are moist, also rank near the top in terms of contaminates. Hand dryers blow organisms everywhere, so Dr. Gerba suggests avoiding them entirely.
Dispensers for feminine products is another prominent area for caution.
Given the science, what is the best way to navigate a visit to the public washroom?
The COVID-19 pandemic has created a newfound appreciation for proper hygiene which translates well into prudent bathroom behavior.
First, keep in mind what Dr. Nouri said: lingering is not a good idea, particularly in a crowded restroom. Some experts have suggested a flush and rush approach. And when you flush, put the lid down (if there is a lid) because it is effective in reducing toilet plume.
Close contact with others is not recommended. Social distancing is still an important practice. Whenever possible, wait until a crowded bathroom thins out. Single occupant, single stall lavatories that don’t require shared space, is the best option.
Never place a handbag or cellphone on the floor or sink surface.
Use the first stall — research consistently points to the middle stall as the most frequently used and most contaminated toilet.
It is of critical importance to wash your hands properly. This means 20 to 30 seconds of soaping under hot water. Use a paper towel to cover your clean hand as you turn off the faucet and open the door to exit.
Finally, once out of the restroom, employ the hand sanitizer of your preference.
The good news is that the pandemic has enlightened restroom design. In the future, more touchless features are coming our way.
Here is Martin Oaks’ related blog on handwashing techniques. https://blog.