It has it's own biome - a biome that survives microwave radiation.
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Although previous studies found distinct communities of microbes in kitchen appliances such as dishwashers1 and coffee machines2, this is the first time that the microwave oven has been investigated for having its own microbiome. The research, published today in Frontiers in Microbiology3, adds to existing work challenging a common misconception: that microwave radiation heats up and completely kills bacteria that cause food-borne illness, such as Escherichia coli and Salmonella.
“We’ve all been taught, from like the 1980s, that if you use a microwave oven, 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 shines a spotlight on potential pathogens in these appliances, especially shared ones.
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a tip of the hat to Sukie