02 August, 2017
The researchers even goes as far as saying your kitchen has more germs than your toilet, thanks to your sponge.
German researchers studied the germs on sponges and found out they get so dirty they should be thrown out every week.
In order to conduct the study, researchers used a method called DNA pyrosequencing to sequence the DNA of 28 samples of bacteria collected from 14 different kitchen sponges taken from private households in Baden-Württemberg, Germany. This can turn into a serious health hazard seeing how sponges are supposed to clean the dishes and cutlery that we use to eat.
And if you thought cleaning the sponge by the various method is enough, you must rethink.
Most of the bacteria found isn't harmful, but there were pathogens that could lead to infections in humans.
"The aim of this study was to investigate the bacterial microbiome composition of used kitchen sponges, to visualize the spatial distribution of the bacteria within the sponge tissue and to identify factors that influence the microbiome composition", wrote the authors. Meaning that efforts to control the bacteria multiplying in your sponge might actually be making the situation worse.
What makes sponges - which the team call "the biggest reservoirs of active bacteria in the whole house" - so problematic isn't just their damp, porous structure, which provides an optimal breeding ground for microbes.
The researchers also said that "kitchen sponges not only act as a reservoir of microorganisms, but also as disseminators over domestic surfaces, which can lead to cross-contamination of hands and food, which is considered a main cause if food-borne disease outbreaks".
"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 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. The microwave will kill the bacteria by heating the water in the sponge.
Moreover, the bacterial species from the "sanitized" sponges contained more bacteria related to diseases.
Luckily, sponges are not an expensive item so it is not too much of a haste changing them on a weekly basis, but you do need to keep in mind to do that.
The study also showed that even sanitized sponges had high bacteria counts, so the researchers say the best thing to do is to invest in a new sponge every week.
However, while many would argue this is all the more reason to sanitise them, sponges that were regularly washed showed significantly higher levels of bacteria.
There are few old wives tales surrounding how to clean off your sponge. "We therefore rather suggest a regular (and easily affordable) replacement of kitchen sponges, for example, on a weekly basis", wrote the researchers.
