Your Microwave Oven Hosts Its Own Microbiome
Extreme organisms, or “extremophiles,” are known for their ability to thrive in extreme environments such as hot hydrothermal vents, freezing Antarctic ice, and deep within Earth’s crust. Recently, researchers have discovered these resilient microbes in an unexpected location: microwave ovens.
While previous research has uncovered unique microbial communities in appliances like dishwashers and coffee machines, this study is the first to explore the microbiome of microwave ovens. The findings, published in Frontiers in Microbiology, challenge the common belief that microwave radiation kills all bacteria, such as E. coli and Salmonella, that can cause foodborne illnesses.
We’ve been led to believe since the 1980s that microwaves eliminate all bacteria by heating, says Jason Tetro, a microbiologist from Edmonton, Canada. He emphasizes that this study is significant for highlighting potential pathogens in microwave ovens, particularly in shared spaces.
Microwaves Don’t Sterilize Everything
Alba Iglesias, a microbiologist at the University of Valencia, and her team examined 30 microwave ovens from various settings, including homes, shared offices, and laboratories. They collected samples and cultured them to identify the microbial species present, also sequencing the DNA to assess bacterial diversity.
The study identified 101 bacterial strains, with dominant ones from the Bacillus, Micrococcus, and Staphylococcus genera—bacteria typically found on human skin and frequently touched surfaces. These bacteria were present in all microwave types but were more common in household and shared appliances. Some bacteria linked to foodborne illnesses, like Klebsiella and Brevundimonas, were found in household microwaves.
Microwaves used in laboratories showed the highest bacterial genetic diversity, harboring both common kitchen bacteria and extremophiles capable of withstanding microwave conditions, such as radiation and high temperatures.
You don’t have to visit exotic locations to find diverse microorganisms,” remarks Manuel Porcar, a co-author from the University of Valencia.
The researchers speculate that the extremophiles in microwaves may have evolved to survive repeated radiation exposure and could be useful in biotechnology applications, like cleaning up toxic waste. Future research will explore how microwave use affects these bacteria over time.
For the public, the study’s takeaway is straightforward: “A microwave is not a sterile environment,” Porcar notes. It’s not a breeding ground for dangerous pathogens, but regular cleaning of your microwave is advisable to reduce potential bacterial buildup, similar to maintaining kitchen hygiene.
Read the original article on: Nature
read more: The Human Microbiome is Going Extinct, Scientists State
