Your Kitchen Sponge Is Gross, and Cleaning It Isn’t Helping

Stop doing this. Photo: Aleksandar Blanusa/Getty Images/iStockphoto

Maybe you saw the MythBusters on the secret grossness of everyday items like the kitchen sponge, and resolved to clean up your act by tossing the bacteria-ridden thing in the dishwasher or microwave every so often. Alas, according to a new study from the journal Scientific Reports, the ways you’ve been cleaning your sponges may be entirely ineffective.

A team of researchers in Germany discovered that cleaning sponges by putting them in the microwave or boiling them in water were ineffective in reducing their bacterial load. In fact, regularly cleaned sponges weren’t any cleaner than those that were never cleaned.

Kitchen sponges are known to host “risk group 2” bacteria, which cause diseases that, although preventable, would be something anyone would want to avoid. One such bacteria, Moraxella osloensis, has also been known to make your laundry stink, and according to the researchers, may be what makes your kitchen sponges stink, too. Sponges that were washed didn’t show any decrease in disease-related bacteria like Moraxella osloensis, and may even have increased their presence due to resistant bacteria that survive the cleaning and reproduce quickly.

The researchers don’t suggest that you should stop using kitchen sponges altogether, but they do recommend a preferred method of dealing with them:

“From a long term perspective, sponge sanitation methods appear not sufficient to effectively reduce the bacterial load in kitchen sponges and might even increase the shares of [disease]-related bacteria. We therefore rather suggest a regular (and easily affordable) replacement of kitchen sponges, for example, on a weekly basis.”

As for me, I’m going to go ahead and blow up my remaining kitchen sponges and never, ever use another one. Don’t worry — I’ll make sure those explosions are ones of which the MythBusters would be proud.

Your Kitchen Sponge Is Gross, and Cleaning It Isn’t Helping