Cleaning this dirty kitchen item might not be helping

Cleaning this dirty kitchen item might not be helping

If you have a sponge at your kitchen sink, you probably use it a lot.

It gets quite a workout as you wipe counters and scour pans. Every so often, you might think it’s time to pop it in the microwave, dishwasher or pot of soapy boiling water to give it a good clean. Don’t do it.

You’re only making your sponge germier.   

A study published in Scientific Reports suggests that regularly sanitized sponges did not contain less bacteria than uncleaned ones. This study found that microwaving or boiling them could kill some weaker bacteria, but the stronger bacteria remain and quickly fill in the freed-up space, leaving the sponges in the same condition — or worse. Methods people use to try to disinfect sponges simply aren’t sufficient to effectively reduce the bacteria and instead increase the most stubborn, stinky germs.

The study’s authors wrote that this effect is similar to antibiotic resistance in humans. In other words, what doesn’t kill the bacteria makes them stronger.

Kelly Blair, an infection preventionist at Advocate Good Shepherd Hospital in Barrington, Ill., says don’t even think about trying to clean dirty sponges. There’s only one place for them.

“Toss them. It’s that simple,” says Blair. “But knowing when to toss them – that’s trickier.”

The authors of the sponge study suggest tossing and replacing your kitchen sponge weekly, but Blair isn’t convinced. She says rather than giving yourself a time deadline, consider how often you use your sponge. If you use it only once a day, replacing it weekly is probably too often. On the other hand, if you’re a heavy-duty user, tossing and replacing weekly might be necessary.

Although it’s not always easy to know for sure, she says replacing your kitchen sponge just before it starts smelling or feeling slimy is advisable.

“Usually you can tell when it’s time,” she says.

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  1. Sharon McKinney August 28, 2019 at 8:32 am · Reply

    I place the sponge in diluted bleach for about 15 mins. I would think that would do it!

  2. Nancy Jacobson July 27, 2020 at 11:53 am · Reply

    Why not just use a washable dish cloth and get a clean one every day.

  3. Janis Kohlenberg July 27, 2020 at 10:02 pm · Reply

    I use paper toweling because it can be disposed of! It costs more than sponges or dish rags, but I feel that it is the safest way to simply get rid of bacteria! I can always save money in other areas.

  4. I put a splash of bleach in my dish water and then wash my dishes. The sponge goes in the dish water so I figure that it can’t be all that bad. I use a dish rag to wipe down the counters not the sponge.

  5. Tossing sponges every week, or so, creates sooo much garbage. Most of these dish sponges are made with plastic or other material that does not degrade very quickly. Letting these sponges dry well after each use, or over night will keep the germs at bay. Also, bleach is where it’s at. Washable dish clothes are also a great way to keep creating garbage.

  6. Donna Iverson July 2, 2021 at 1:45 pm · Reply

    What about an ultraviolet light?

  7. Whenever I make dishwater, my main ingredient is bleach. I have always used prior to the pandemic because it keeps my dish cloth clean and when I wipe down my appliances it also helps.

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health enews Staff
health enews Staff

health enews staff is a group of experienced writers from our Advocate Health Care and Aurora Health Care sites, which also includes freelance or intern writers.