Kitchen sponges harbor more bacteria than kitchen brushes, study shows

“Salmonella and different micro organism develop and survive higher in sponges than in brushes, the reason being that sponges in day by day use by no means dry up,” mentioned Trond Mretr, a analysis scientist at Nofima, a Norwegian meals analysis institute.

“A single sponge can harbor the next variety of micro organism than there are individuals on Earth,” mentioned Mretr, an writer of a brand new research, which revealed on-line within the Journal of Utilized Microbiology.

Whereas many micro organism should not dangerous, these which are — like salmonella — can unfold from sponges to fingers, kitchen surfaces and gear and probably make individuals sick, he mentioned.

“The sponge is humid and accumulates meals residues that are additionally meals for micro organism, resulting in fast development of micro organism.”

What shocked the researchers most about their findings was that it did not actually matter how individuals cleaned their sponge or how typically.

“That the way in which the shoppers used their sponges didn’t matter a lot concerning development of micro organism. It is vitally troublesome for shoppers to keep away from bacterial development within the sponges so long as the sponges should not changed day by day,” Mretr mentioned.

The analysis on the used sponges and brushes builds on a lab-based research revealed final 12 months by the identical crew of researchers, which discovered that dangerous micro organism survived higher in sponges than in brushes.

In the USA, the USDA mentioned that that microwaving or boiling kitchen sponges could scale back “among the bacterial load,” nevertheless these measures alone should not sufficient to make sure your sponge will scale back cross-contamination. It suggested to purchase new ones ceaselessly.

The analysis was a part of a European Union-backed challenge on meals security.

Sponge vs. brush

The researchers collected kitchen sponges from 20 individuals residing in Portugal and 35 brushes and 14 sponges from individuals residing in Norway.

An earlier survey of 9,966 individuals by the analysis crew discovered that sponges had been generally used for cleansing in kitchens within the majority of 10 European international locations, with brushes the dominant cleansing utensil for laundry up in solely two international locations — Norway and Denmark.

The sponges had been all used for laundry dishes — scrubbing pots and pans, and 19 of the 20 sponges from Portugal had been used 5 to 6 occasions per week or extra typically. Of the brushes collected in Norway, 32 out of 35 had been used 5 to 6 occasions per week or extra. The sponges collected in Norway had been used much less ceaselessly.

No pathogenic micro organism (that causes illness) was discovered within the brushes or the sponges. Nevertheless, total micro organism ranges had been decrease in used brushes than sponges. Comparable varieties of non-pathogenic micro organism had been discovered within the two cleansing utensils.

When the researchers added salmonella micro organism to the brushes and sponges, they discovered a major discount within the salmonella numbers in brushes allowed to dry in a single day. However there was no discount for brushes saved in a plastic bag or for sponges no matter storing circumstances.

The house owners of the sponges and brushes shared how lengthy they usually used their sponge or brush and the way they stored their cleansing utensils clear — rinsing with water, washing with cleaning soap and water, putting them within the dishwasher or bleaching.

Nevertheless, none of this stuff made a tangible distinction — one thing that shocked the researchers. The important thing takeaway from the research was that brushes, which dry between use, have decrease numbers of micro organism.

“For the reason that brush dries very quick, dangerous micro organism will die. Additionally, most brushes have a deal with which prevents you from direct hand contact with potential dangerous micro organism, in distinction to sponges,” he mentioned.

“I encourage shoppers to strive a brush as an alternative the subsequent time they should change their sponge.”

What to do
Whereas research authors really helpful the bristles of a brush over the squish of a sponge, Cath Rees, a professor of microbiology on the College of Nottingham who wasn’t concerned within the analysis, she mentioned would proceed utilizing a sponge to clean dishes. For her, the important thing takeaway was that drying dish sponges and cloths between use was a good suggestion.

“The primary message I get is that they didn’t discover any proof of pathogenic micro organism on the sponges or brushes taken from a variety of home settings and due to this fact there is no such thing as a proof that these things are a major supply of contamination in regular home settings,” Rees mentioned.

“If there have been some low ranges of pathogens left in your material, they’ll develop fairly slowly (they develop optimally at physique temperatures), so you wouldn’t count on to see a lot development of those, and this matched their outcomes — in moist situation there was some restricted development, in drying circumstances the numbers both stayed the identical or declined,” she defined.

Markus Egert, a microbiologist at Furtwangen College in Germany who has performed comparable analysis, mentioned he already used brushes to clean up his dishes, which he cleaned within the dishwasher. If individuals most well-liked a sponge, Egert, who was not concerned on this research, really helpful utilizing a brand new one each two to 3 weeks.

“Brushes are the higher selection to wash dishes, from an hygienic viewpoint. This might need been anticipated earlier than, however the authors show it with some good experiments. Nevertheless, based mostly on my expertise individuals love utilizing sponges.”