'Extremophiles' are Organisms that can survive, and even thrive, in the harshest environments, including within glowing hydrothermal vents, subantarctic ice, and the crushing pressures of the Earth's crust. Now they've been discovered in a more mundane setting: microwaves.

Although previous studies have found distinct communities of microbes in kitchen appliances such as dishwashers 1and coffee machines 2Found this is the first time using the microwave on its own Microbiome was investigated. The ones in todayFrontiers in Microbiologypublished research 3contributes to existing work that challenges a common misconception: that microwave radiation causes bacteria that cause food poisoning, such asEscherichia coliandSalmonella, heats up and kills completely.

"We've all been taught since the 1980s that when you use a microwave, it heats everything up - it kills everything," says Jason Tetro, a freelance microbiologist known as 'The Germ Guy' in Edmonton, Canada. This study is "important," he says, because it sheds light on potential pathogens in these devices, particularly shared devices.

Not everything that is heated is killed

Alba Iglesias, a microbiologist at the University of Valencia in Spain, and her colleagues tested 30 microwave ovens - including some in homes; some shared in large spaces such as offices; and some used in laboratories to heat samples and chemical solutions . The team then cultured their samples in Petri dishes and determined the genus of microbes grown. They also sequenced the DNA of the material wiped from the microwave ovens to get a sense of the bacterial diversity within the devices.

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