Bacteria Flourish in Public Restrooms

Study Shows Many Strains of Bacteria Are Common on Surfaces in Public Restrooms

Medically Reviewed by Laura J. Martin, MD on November 23, 2011
From the WebMD Archives

Nov. 23, 2011 -- You don't have to be a germophobe to get anxious about using public restrooms. And now new research shows what many people have long suspected -- bacteria are plentiful in men's and women's public restrooms.

Using a high-tech genetic sequencing tool, researchers identified 19 groups of bacteria on the doors, floors, faucet handles, soap dispensers, and toilets of 12 public restrooms in Colorado -- six men's restrooms and six women's restrooms.

The new findings appear online in PLoS ONE.

Many of the bacteria strains identified could be transmitted by touching contaminated surfaces. For example, toilet surfaces were found to have bacteria that are commonly associated with feces.

Skin-associated bacteria such as Staphylococcus aureus were found on faucets and other fixtures we touch with our hands. And floor surfaces -- which had the most diverse strains of bacteria -- were contaminated with a lot of bacteria found in soil.

Skin was the main source of bacteria on all surfaces, though.

There were some differences seen in men's and women's restrooms, the study showed. For example, Lactobacillus, a vagina-associated bacterium, was obviously more commonly seen in women's bathrooms.

Hand Washing Is Key

The results of the study didn't surprise researcher Gilberto Flores, PhD of the University of Colorado in Boulder. "I anticipated that most of the surfaces would have evidence of human bacteria."  

Most of these bacteria are not harmful, he says.  "As long as you wash your hands with soap and water, you will be fine."

Some people may take it a step further, Flores says. "We found dirt-associated bacteria on the toilet handle in one stall, which indicates that people use their foot to flush the toilet."

His advice? Use discretion if you can, but most public restrooms are OK. Now Flores and his colleagues will be looking at bacteria in residential kitchens, using the same technology.

Show Sources


Gilberto Flores, PhD, University of Colorado, Boulder.

Flores, G.E. PLoS ONE, 2011.

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