Men vs. Women: Whose Offices Are Germier?

Study Finds Bacterial Contamination Common in the Workplace

Medically Reviewed by Michael W. Smith, MD on May 30, 2012

May 30, 2012 -- If you're reading this at work, brace yourself. A new study shows that typical offices have hundreds of types of bacteria in them, and men's offices have the most.

Researchers report finding more than 500 different types of bacteria on common surfaces in offices in three major U.S. cities. And, perhaps less surprisingly to some people, they found that men's offices are more contaminated than women's.

"Humans are spending an increasing amount of time indoors, yet we know little about the diversity of bacteria and viruses where we live, work, and play," says lead researcher Scott Kelley, PhD.

The San Diego State University biologist and his team swabbed five common office surfaces -- chairs, phones, desks, computer mice, and keyboards -- in 90 different offices, 30 each in San Francisco, New York, and Tucson.

The research team, which was partially funded by the Clorox Corporation, found bacteria on nearly every surface they tested. Most of it came from the office workers themselves. Coughing and sneezing accounted for a good deal of the bacteria, as did shedding from the skin. However, a substantial amount came from deeper inside the body.

"We also found a surprising number of bacterial genera associated with the human digestive tract," the researchers write in the study, which appears today in the online journal PLoS ONE.

If all this sounds rather alarming -- or simply gross -- the researchers point out that there is likely little cause for concern for the vast majority of people who spend eight hours a day in an office: "[M]ost of the human-associated bacteria we found ... would only be a potential problem with severely immune compromised individuals."

On top of that, the researchers say that the dry, cool atmospheres of most offices do not lend themselves to bacterial growth.

Men Are Greater Source of Bacteria Than Women

As for the main suppliers of the bacteria, Kelley and colleagues say that men are responsible for a higher germ count than their female co-workers. Part of that may be explained by the fact that men are, in general, larger than women, which means they have more surface skin to provide a breeding ground for bacteria. However, the researchers cite previous scientific literature to offer another possible explanation.

"Men are known to wash their hands and brush their teeth less frequently than women, and are commonly perceived to have a more slovenly nature," the researchers write.

And the Germiest Spots Are ...

Office co-workers are not the only source of bacteria. Dirt is another main supplier of contamination. And the most common surfaces on which bacteria were found? Telephones and chairs.

The researchers also found that the San Francisco offices they tested were less contaminated than those in New York and Tucson. They were not sure why this should be the case.

The researchers hope that these types of bacterial profiles of office spaces will help public health officials get to the bottom of disease outbreaks that can occur in office settings.