Replacement Toilet Lids and Seats - Study: Your Kitchen Sponge Has More Germs Than Your Toilet - This Old Toilet 800-658-4521
Colorful cleaners or nightclubs for bacteria? (Photo: Shutterstock)
Do you wash your dishes in the toilet? In a study published in Scientific Reports, researchers from Germany showed just how germy 14 different used kitchen sponges actually were with more bacteria than typically found in the toilet. I say typical because you know the common saying, "different people, different toilets."
The team from Justus–Liebig–University Giessen (Massimiliano Cardinale and Sylvia Schnell), German Research Center for Environmental Health (Tillmann Lueders), and Furtwangen University (Dominik Kaiser and Markus Egert) used 454–pyrosequencing of 16S rRNA genes and fluorescence in situ hybridization coupled with confocal laser scanning microscopy (FISH–CLSM) to analyze the bacteria content of used kitchen sponges including those that are regularly "cleaned". (I know what you are thinking, it's been a while since you've used pyrosequencing, fluorescence in situ hybridization, and confocal laser scanning microscopy together.) They found not one, not two, but 362 different types of bacteria. And many of these are not just benign, friendly bacteria. Five of the 10 most frequently detected bacteria species had "pathogenic potential." In other words, they could cause problems and disease in humans, i.e., you. Yes, your kitchen sponge is a huge and shady nightclub for bacteria.
Like a nightclub, regular cleaning may help but many sponge owners don't seem to be cleaning their sponges adequately. Microwaving or boiling the sponge in the laboratory helped significantly reduce the sheer amount of bacteria. However, the researchers found that sponges that the sponge owners claimed were regularly cleaned did not contain less bacteria than uncleaned ones. This is another example of the adage, just because something (or someone) doesn't look dirty doesn't mean that it isn't.
If you have a stinky sponge, then you may want to blame Moraxella osloensis. This stinky bacteria is often responsible for making laundry smell and appeared abundantly in the sponges. Interestingly, the researchers found that boiling or microwaving the sponges could even increase the load of Moraxella osloensis, probably by killing off other better smelling bacteria and allowing the Moraxellamore room to reproduce at the bar of the nightclub...so to speak. While Moraxella osloensis is not a common cause of infections in humans, there have been cases.
Washing your pots and pans doesn't clean your kitchen sponge. (Photo: Shutterstock)
Why would your kitchen sponge have more bacteria than your toilet? After all, don't you poop in your toilet and not your kitchen sink? (Please don't provide any other answer than yes.) Well, unless you prepare food and eat often while on the toilet, you handle a wider variety of substances like food and rubbish more frequently in your kitchen, while also touching yourself. Moreover, as studies have shown and hand hygiene warnings have emphasized, you may not be washing your hands as regularly or as correctly as you should before, during, and after food preparation. Additionally, there is generally more traffic in your kitchen than your bathroom...traffic meaning different people rather than cars and trucks. Your bacteria-laden and dirty family and friends (because that's what they are) bring more contamination to the kitchen than nearly any other location in your apartment or house.
What should you do then about the stinky nightclub of bacteria that is resting besides your kitchen sink? First, don't freak out. No matter how lonely you may feel at certain times, you are never alone. Bacteria is everywhere, although they may not be very talkative or like Netflix. Secondly, wash your hands regularly and properly. Third, clean your sponge regularly and properly, such as boiling your sponge, microwaving it on high, or soaking it in bleach (a quarter to half of a teaspoon of concentrated bleach per quart of warm, not hot water) for at least a minute. A Michigan State University web site includes some tips on how to do this such wetting your sponge and removing any metal before you microwave it so it doesn't catch fire or explode (both of which are bad). The Academy of Nutrition and Dietetics recommendscleaning your sponge daily. Fourth, replace your sponge frequently, even if it looks OK. You can't see bacteria but they can see you. While cleaning your sponge regularly properly can help the bacteria count down, you should still replace your sponge regularly. The researchers recommended once a week while others (such as a microbiologist in an article in Self) have said about once a month, which is probably more frequent than you currently replace your sponge. Somewhere in this range is probably reasonable, depending on how often you use the sponge, whether you regularly clean the sponge, and what you do with it. Finally, if your sponge smells, just throw it away. Moraxella osloensis stinks.