If You Think Microwaving Your Sponge Keeps It Clean, You're Dead Wrong

cleaning microwave
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Is part of your cleaning routine nuking your smelly sponge in the microwave in attempts to give it a new life?

Sorry for this, but your efforts are fruitless. 


According to a recent study by German researchers, microwaves -- and even special products and antibacterial soap -- only kill the weakest bacteria on your sponge; the strongest ones still survive. In fact, they'll take advantage of the vacant space and reproduce.

In the study, researchers examined the DNA and RNA samples from 14 used sponges and identified 362 different species of bacteria inhabiting them. That's not even the shocking part. Scientists found 82 billion bacteria in a single cubic inch of the sponge. 

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If you need help processing that: Margus Egert, a microbiologist for the study, said that it's the same density of bacteria found in human stool samples.

Don't totally freak out just yet. As study coauthor Massimiliano Cardinale explained to WBUR's "Here & Now," the bacteria they found wasn't salmonella, but rather "opportunistic pathogens," which don't pose a threat to healthy people -- although they could for those with weak immune systems.

The reasons sponges are breeding grounds for bacteria are because not only does the sponge constantly come into contact with food and skin, but it's typically warm and wet. 

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Egert suggests throwing out your sponge every week or so. But if that feels wasteful (and costly) to you, he said to put it through the washing machine with bleach, detergent, and the hottest setting. Then you can use the sponge again -- just not in the kitchen anymore.

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