Let this soak in: your kitchen sponges are a hotbed of bacteria.
A DNA analysis of the so-called cleaning tools at a university in Germany found 362 different types of bacteria.
Researchers at Furtwangen University analyzed 14 different kitchen sponges and discovered they’re filled with more bacteria than a toilet. Sponges, which are moist most of the time and designed for absorption, tend to pick up bacteria like E. coli, salmonella and Staphylococcus as you clean your dishes and counters or just from you touching it.
“Despite common misconception,” the study read, “it was demonstrated that kitchen environments host more microbes than toilets.”
Most of the bacteria found isn’t harmful, but there were pathogens that could lead to infections in humans. Sponges can also spread bacteria to places where it previously wasn’t.
“Kitchen sponges are likely to collect, incubate and spread bacteria from and back onto kitchen surfaces, from where they might eventually find their way into the human body, e.g. via the human hands or contaminated food,” the study said.
The recommended methods for cleaning sponges includes microwaving for over a minute, soaking in a bleach solution for five minutes or using products with hydrogen peroxide, isopropyl alcohol, ammonia or vinegar — all of which have been said to kill 99.9% of bacteria.
But there’s always that .1%. Plus, the Furtwangen researchers found that microwaving the sponges — which can actually stink up your kitchen — doesn’t kill all of the dangerous bacteria. They discovered that any sterilizing method alone only reduces bacteria by about 60%. Also, some bacteria actually increased after the sponges were cleaned, thanks to resistant bacteria surviving the sanitation process and rapidly recolonizing.
The researchers recommend changing sponges weekly.
Similarly, if you use loofahs, those are also prime real estate for bacteria.