Here’s what we know: On August 7, academics published a report outlining the findings of an investigation into the bacterial communities residing in kitchen microwaves, microwaves used in shared large spaces (think: universities or nursing homes), and laboratory microwaves. The Kitchn spoke with Manuel Porcar, a microbiologist at the University of Valencia and Darwin Bioprospecting Excellence, and one of the lead researchers on this study, to understand if there’s really any cause for concern.
So, how do potentially harmful bacteria even get into your microwave in the first place? It mainly comes from cooking certain foods there. “Raw fish and raw meat, particularly chicken, can have a high bacterial load and some pathogens,” Porcar says. If you’re leaning on your microwave or microwave oven to quickly meal prep your turkey breast or steak for the week, you could introduce germs to your appliance.
Raw meat can contain pretty serious bacteria, according to The Centers for Disease Control and Prevention (CDC). Germs, like Campylobacter, salmonella, or Clostridium perfringens, can lead to foodborne illnesses. Catching one of these ailments can cause you to experience a wide variety of symptoms which may lead to symptoms like diarrhea, stomach pain or cramps, nausea, vomiting, or fever, reports the CDC.
Porcar explains that despite these findings appearing alarming, they mainly found few heat-resistant bacteria that were pathogenic — or capable of causing human diseases. “We also found some radiation-resistant ones, particularly in lab microwaves,” Porcar explains. “Of those, we can highlight Deinococcus or Hymenobacter. Those super-resistant bacteria are environmental ones and not pathogenic.”
While most of the findings don’t appear to exhibit major harm to humans, there is one meat that Porcar suggests keeping a watchful eye out for. “Kielbasa can be pathogenic,” he says. So if you find yourself heating up the sausage often to toss in pasta or brioche buns, you may want to stick to cooking those on the stove or the grill to avoid potential run-ins with germs.
If the idea of bacteria throwing a rager in your microwave skeeves you out, you can take a few simple steps to prevent them from spreading in your appliance. “Food should not be placed in direct contact with the oven’s glass tray, and food particles and debris should be cleaned, as you would on the kitchen table, for example,” Porcar says. You can mix up a batch of dishwashing soap and diluted bleach to get rid of most of the germs; that way, you can go back to heating up your favorite quick-prep meals without all the stress.
