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Microwave by M.E. WilliamsDo you use a sponge to wash your dishes? Right now, I can promise you one thing: that sponge is, unfortunately, one of the dirtiest things in your house... unless you already perform the following regimen.

For one thing, it lives near the kitchen sink, which is the germiest area of most homes. For another, all those little chambers that make a sponge so good at soaking up water also make it good at holding onto germs that can make you and your family ill. Some people run their sponges through the dishwasher, but that does little to kill bacteria.

There's a fast and easy way to disinfect your dish sponge, which you should do as often as every other day. Keep reading to find out what to do!

Simply wash the sponge with hot water and soap, rinse it, and put it in your microwave. Microwave at 100% power (High setting) for 1 to 2 minutes. This will kill most of the germs living in the sponge: most die in the first 30 seconds, but E. coli can hang on a little longer. You can put the sponge in a small, microwave-safe dish of water, if you prefer, before putting it in the microwave.

Be careful: keep an eye on the sponge while it's "cooking," to make sure it doesn't burn. It will be HOT when it's finished. Let it cool in the microwave for a while, or wear a heat-resistant glove, like a silicone oven mitt, to take it out.

Don't make the mistake that many people made when this tip was featured on a morning talk show a while ago. There was big drama because the guest neglected to mention that the sponge needed to be wet. Plenty of people cooked their dry sponges in the microwave and wound up with a stinky, burned mess.

Another potential pitfall: this is for sponges only. You can't put anything metallic, including dish scrubbers or steel wool, in a microwave. But any sponge or scrubber can be soaked in a diluted bleach solution for similar (albeit messier) microbe-busting results. Whatever you do, it should be done any time your dishes came in contact with raw meat or poultry, or at least a few times a week.

Even disinfecting your sponge won't make it last forever, so be sure to squeeze the water out of your sponge after each use, and start over with a new sponge every few weeks. Also, always keep two sponges or cloths in your kitchen: don't use the same one on your dishes that you use to clean the counter. (In my house, the retired, disinfected dish sponge becomes the counter-cleaning sponge.)

For more on this topic, see this WebMD article and this New York Times article.


  • Laura

    I really appreciate all of the ideas for disinfecting sponges. I intend to alternate using these ideas according to what is convenient at the time. Also, I think that retiring the counter sponge to the sink makes more sense since the sink has more germs.

  • lee

    i just throw it out. same goes for my toothbrush, razor, etc.

  • cindy

    In my kitchen I always have 2 sponges in use at once. I use a regular sponge for the counters and use a SOS sponge for the pots and dishes. THis way there is no confusion which sponge is which and the SOS has a flat surface for when you don't need the scrubby part. You can microwave both at the same time, just for a little longer.

  • Gldnldy

    First of all I use the sponges with the scrubber on one side, but only for cleaning dishes before placing in dishwasher. I have a Septic tank so liquid bleach is out. I always use a cleasner that has bleach in it and use the sponge to scrub the sink twice a day. Lysol or Mr. Clean concentrate one part to 10 parts water works for me on counters, stove etc. with paper towels. The sponge never meets up with my counters or other food prep areas. Watch what you use to clean microwave out with as chemicals change properties when nuked. Orange Glow is best.

  • Nancy Fisher

    I pour boiling water over my sponge and when it is cool< I wring it out and pour peroxide over it and let soak and finally rince well with hot water from the tap. I've always assumed that should kill anything.

  • Joan Ahern

    use the bleach and water - always keep it on the side and you can wash your dishes and clean your counters all with the same sponge.
    You can't get crazy - if you listened to everything about germs in your house you could go through a gallon of bleach in a day.

  • Joan Ahern

    use the bleach and water - always keep it on the side and you can wash your dishes and clean your counters all with the same sponge.
    You can't get crazy - if you listened to everything about germs in your house you could go through a gallon of bleach in a day.

  • Vivi

    I am disabled and live alone and I do not worry about germs. Going to die anyway.

  • Bev

    Sponges are great for washing cars - period. For cleaning dishes, kitchens or bathrooms, sponges are essentially "petri dishes" that efficiently mix and grow bacteria and cross-contaminate surfaces. Use paper towels, or CLEAN laundered cloths instead (laundering after use, of course).

  • M.E. Williams

    I'm the author of this article. Here are a few general replies and a few specific ones....

    Bev - the fact that sponges are petri dishes *unless you disinfect them* is the topic of this article. But if you follow the links, you will see that medical studies have shown that it's possible to keep a sponge clean with very little effort. If someone uses dishcloths, they definitely need to be sure to use a clean one every day or after they wash a plate that had raw meat (beef, poultry, pork) on it. If that happens at lunchtime - tough! Time for a new cloth. But being a dishcloth user, you know how it is! :) (Days Of The Week dishcloths are a good idea.)

    Ann & Brandi - no "Duh": the "retired" sponge is kept clean too. It's just that we usually retire a sponge to counter-cleaning when it starts to shred a little. And we wouldn't eat food that spilled on our *clean* counters.

    Laura - retiring the counter sponge to become the dish sponge doesn't make sense in this house for several reasons, some personal. But the main one is that dish sponges see a lot more water and agitation, so we "retire" a sponge when it becomes annoying to wash with because little pieces are coming off of it. Or once a month, whichever is first.

    In a general reply to all the bleach comments, I would think it would be obvious why I skip the use of chlorine bleach as much as possible: too much danger of ruining clothes with stray splashes. Also, toxic fumes. (No, I would NOT heat bleach in the microwave with the sponge.) Furthermore, chlorine bleach is best used to sanitize hard surfaces, not soft ones, even though it works for soft ones. It weakens fibers too much.

    Studies show that running your sponge in the dishwasher, even on the "sanitize" setting, is simply not as effective as the microwave trick or chlorine bleach.

    Clorox wipes are useful, but most of the disinfectants used in those sorts of products, including Lysol, are neurotoxins, and on top of that, disposable wipes aren't really eco-friendly by virtue of being, well, disposable! :) Why use a harsh chemical when you can just use the power of boiling water, anyway? (& what's the point of using a disinfectant wipe to mop up spilled coffee or flour?)

    (This isn't to say that I never use Clorox wipes on the counter - I do. But I do think it's good to use them sparingly. The same goes for cleaners like Mr. Clean and 409, which go into our water supply... try something like Simple Green or Method's all-purpose cleaners, which are at least non-toxic.)

    Lee - you should do this every couple of days. Your business is your own, but I think that's really too often to be throwing away perfectly good anythings that just need disinfecting. :)

    As far as cleaning out your microwave itself - follow manufacturer's instructions. Or put a bowl or Pyrex measuring cup with water and lemon juice in the microwave, heat it for about two minutes or so, and then use a damp cloth to wipe the vapors out of the microwave. Unless you want your food to taste like cleaners for weeks, don't use cleaners to clean your microwave! That's an issue well past the "cleaners can change when heated," which is also true. But if you clean your microwave frequently - which you should do anyway - and keep up with spills, you shouldn't have any need for any kind of heavy-duty cleaner. Most of what you use to clean your microwave should be water. Really bad spills can sometimes handle a drop or two (at most) of dish soap, but be sure to wipe the area with a cloth and plain water a few times afterwards.

    Joan and Vivi - I agree that people are probably a little too paranoid about germs, but the kitchen is one place in the house where you *should* be paranoid about them. :) (To some degree, anyway!)

  • Diane

    I have tried this many times. i soak them thoroughly and they still end up stinking up the entire house as they're microwaving and continue to smell afterwards.

    i don't know what it is though but it seems like even when the sponges are kept in a place where they can dry out they still get incredibly stinky after only a few days of use and that stink NEVER goes away!

    maybe i use them too frequently because it feels like i end up washing the dishes up to 4 times a day so maybe they just never have a real chance to dry out?

    anyways, has anybody who has tried the microwaving trick had the same problem with stinkiness as me? was this was the lemon juice was used for?

  • M.E. Williams

    Diane - This may sound weird, but try changing sponge brands.

    We generally use the same brand, and are happy with it, but once we tried some Casabella sponges. They were advertised as having an antimicrobial treatment, and a good shape for cleaning (though the ones we already used also have a good shape). After we'd used it for a few hours, it started to stink with a distinct "moldy" smell, and no matter what we did, it never stopped. Never bought them again.

    I'd tell you the brand we use, which never has any problems, but it's time to buy a new pack... I guess the packaging from the old pack got thrown away a few weeks ago. They're sold at Target and WalMart, among other places, and have concave sides and a slightly convex end. (That is, the long sides curve in, the short sides curve out.) They have a scrubby side with some kind of "fun print" and a sponge side in a bright, light color, usually green, blue, purple, or peach.

    Usually I rinse my sponge thoroughly, squeeze it out, put a bit of dish soap on it, and squeeze it out again, before setting it aside to dry.

    You might also just live in a really humid climate?

  • M.E. Williams

    ... We use the O-Cel-O Light Duty Scrub Sponge made by 3M. It's advertised as having a treatment that "resists bacterial odors" - but I don't know if it's the same one that was in the Casabella sponges.

    At any rate, these sponges never smell (in my experience, anyway) and respond well to the microwaving thing. They also don't rip up nonstick coatings on cookware. However, if you soak them in bleach they -will- fall apart, which is the main reason that the microwave trick is preferable. Plastic and metal scrubbers tend to respond better to bleach.

  • sarah

    I run mine through the great!

  • Maryalice

    I disinfect my kitchen sponge by putting it in the dishwasher everytime I run it. It comes out fresh, just like new everytime.

  • Barb

    Oh for gosh much can a new sponge cost? Why bake the thing when you can have a brand new, sweet smelling one for pennies? Makes no sense to me!!

  • Estelle

    Dirty Sponges on the sink, Yuk! Leave the sponge in the dishwasher and wash it with your dishes. Make sure its snug in place on the top rack. You can even use a clip of some sort to be sure it doesn't fall. The sponge is cleaned regularly and out of sight.

  • doris

    White vinegar and Arm & Hammer b. soda are my indispensable kitchen clean-ups. I wash all fruit with baking soda before it is aaten and I certainly wouldn't like a bleach/smelly sponge! Microwave is not the answer -- new one is. I save a retired one for a floor spill -- ONCE then throw it away!

  • M.E. Williams

    This article isn't about "smelly" sponges, it's about sponges that build up bacteria: what one reader referred to as a "petri dish." This -can- make them stink, but it doesn't always.

    Washing sponges in the dishwasher - even on "sanitize" - may make them smell OK, but that's mostly a mold issue. Because sponges are porous, running them through the dishwasher -does not kill E. coli.-

    So if you want to discount the microwave process by saying, "Oh, I just run them through the dishwasher! They smell fine!" - a better tack would be looking into how long E. coli can actually live on a dry dish. The fact that the dishes are being run in the dishwasher is probably why there's not much effect from the sponge.

    (Cheer up, though: E. coli also lives on just about every human's abdominal area, which is the primary reason why you wash your hands after using the bathroom.)

    Likewise - since it's best, according to medical studies, to disinfect your sponges every couple of days - it's pretty wasteful to throw them out that often.

  • 39 Comments / 2 Pages

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