Tales from the Lab #3: A Tale of Three Keyboards

This month’s installment of Tales from the Lab features a couple of my coworkers from many years ago (names changed for privacy). To preface the story, it’s been a recurring theme throughout my career that chemists innately believe their work areas, lab spaces, computers, etc. must be “cleaner” than the microbiologists they sometimes work with. I believe it’s mostly due to the nature of a microbiologist’s work—we grow cultures in the lab all the time.

What many don’t realize is that there are industry regulations that require the microbiology lab (and any equipment that comes into contact with cultures) must be cleaned on a periodic basis. The chemistry labs don’t have such requirements, and it’s a bit surprising to see the amount of dust that builds up behind/on top of the equipment in a chemistry lab. Dust can harbor more microbes than many people realize.

This story began on a typical work day. The office space that I was assigned was in the same cubicle area as four chemists, and two other microbiologists. For the most part, we all got along well, and would joke around about various things. On this particular day, one of the chemists, whom I will call Jason, was eating a bag of tortilla chips at his desk. The lead microbiologist, Jan, began to laugh as she watched him.

“I thought chemists were supposed to be ‘cleaner’ than we microbiologists are,” she told him, teasing. “You just dropped three big pieces of chip into your keyboard.”

Jason shrugged. “I’ll bet if I turned my keyboard upside down, the only things that fall out of it are those chips.”

I sat across from Jason, and knew his habits probably better than anyone else in the office. “I bet there’s a lot more in there than your chips,” I told him.

Jason proceeded to lift the keyboard and tip it upside-down over the trash can behind his desk. A cascade of debris fell out, and continued to fall out as he shook the thing. Undeterred, he said, “Well, I bet my keyboard is still cleaner than yours. I don’t touch bacteria all day.”

“We do have some contact plates that are about to expire,” Jan interjected with a laugh. “Let’s plate your keyboards and see what grows.”

In the biotech industry, our testing is focused on not contaminating our samples, and aseptic technique is stressed time and again. Microbiologists that have been in industry for any amount of time become accustomed to constantly checking themselves to ensure no sources of bacteria or fungi will be introduced into samples tested in the lab. We wear gloves, use various antimicrobials to disinfect our gloves and the workspaces, and have a never-ending cycle of cleaning the lab and its equipment. After a while, some of these habits inevitably make their way into everyday life as well. (I wash my hands a lot, and am constantly thinking about cross-contamination when I am cooking in the kitchen at home).

After plating Jason’s keyboard, Jan’s, and my own, we placed the plates into an incubator and let them sit for a few days. When we pulled them out to take a look, each one had about the same amount of contamination present, though there was a greater variety of colony types from Jason’s keyboard.

All plates had the typical colonies representative of normal skin flora: Micrococcus and Staphylococcus species. But Jason’s also had a number of what looked to be Bacillus colonies, and even one that was unmistakably a mold (both are typical environmental contaminants). That there were a similar number of colonies on all three wasn’t surprising, but Jason’s keyboard had a greater diversity of organisms (my guess is that it was most likely due to his habit of eating at his desk; neither Jan nor I ate lunch at our desks on a regular basis).

Jason was surprised to see that his keyboard had just as many colonies as ours did, and seemed a bit unnerved by the mold growth. In his defense, mold colonies can grow on agar media from a single spore, and the fact that it grew does not mean he had mold in his keyboard. What I enjoyed the most about this particular story is that it proved microbiologists aren’t that different than chemists when it comes to personal workspaces—although I still maintain that our laboratories are cleaner, in spite of the bugs we work with.