Cooking up food in the office microwave? New study reveals shocking amount of bacteria

Fox News

24-03-2025

A study about office microwaves may have some people rethinking their leftovers for lunch.
Researchers examined the differences in bacteria present in domestic spaces such as a home; in shared-domestic spaces such as an office; and in laboratories.
The study, conducted by researchers in Valencia, Spain, and published in Frontiers in Microbiology, discovered over 100 species of bacteria exist within these spaces – with most of the bacteria being the types found on human skin.
Some of these bacteria can cause foodborne illnesses.
Fox News Digital spoke with Christine Schindler, the New York City-based CEO and co-founder of PathSpot, a health and safety operating system for restaurants and businesses that prepare and serve food, about the difference between at-home and in-office appliances.
"The setting of a microwave fundamentally changes its contamination profile," she told Fox News Digital.
"People rush through lunch breaks, sometimes skipping proper hand hygiene, touching communal surfaces like refrigerator handles before accessing the microwave," she added.
In shared environments like this, microwaves can become bacterial transfer points, she said.
These different bacteria can come from human skin, food splatter and moisture build-up.
Microwaves can become bacterial transfer points.
The presence of bacteria can cause stomach problems such as nausea and vomiting – and the risk increases through the "food-handling sequence," according to Schindler.
"Bacterial risk isn't just about what grows in the microwave – it's about how bacteria move between hands, surfaces and food in a continuous cycle," Schindler said.
Something else the researchers sought to understand is whether microwave radiation has a sterilizing effect on food or if exposure to a wide variety of food and humans had more impact on cleanliness.
"Microwaves kill bacteria in food through heat, not the actual microwaves themselves," Schindler clarified.
"However, this heating doesn't clean the microwave itself or address the bacteria on handles and buttons from unwashed hands," she said.
"This creates a shared responsibility in food safety – you need both properly cooked food and clean microwave surfaces to break the contamination cycle."
The researchers said that what they found "suggests the importance of regular cleaning practices to mitigate potential health risks, as frequent and adequate cleaning with appropriate disinfectants helps to prevent the presence of pathogens associated with these domestic environments."
At home, you're typically dealing with a known group of users and established cleaning routines, something Schindler said makes the difference in maintaining a hygienic environment.
"Office break rooms create more opportunities for bacterial spread," she said. "More users means more hand-to-surface contamination, often less personal accountability for cleaning and greater diversity of foods being heated."
There are some simple ways to keep microwaves clean, even in the office.
Schindler said to wipe down these high-touch areas regularly with food-safe disinfectants, especially in shared kitchens where many people use the same appliance.
For those with more time to spare, she said, heating a bowl of water with lemon juice can loosen up any gunk inside the microwave, making removal easier.