Researchers have been screening samples of kitchen sponges, which are proving to be both incubators and dissemination vectors ideal for these microorganisms.
A German team examined sponges used in the kitchen to do the dishes and clean the worktops. It turns out that these small foam paving stones do not only absorb the soapy water; They also contain billions of bacteria, some of which can cause respiratory tract infections or meningitis.
73 families of bacteria identified
The researchers screened about thirty samples of sponges to identify their bacterial composition. The scientists extracted the bacterial DNA from the samples and analyzed them. Result: 73 families of bacteria were identified. Microscopic analyzes also showed that the bacteria were on the surface of the samples tested. In some cases, the bacterial presence was even very important, with densities ranging from 25 to 54 billion bacteria per cm3.
Our sponges are genuine nests with bacteria and the kitchen would even be an environment conducive to bacterial colonization, more than our toilets, according to a study published in 2012 in Journal of Environmental Health . Because of their porous structure and absorption capacity, sponges are ideal incubators as well as effective dissemination vectors when cleaning a table, refrigerator or stove . It is enough that we put our hands or our food on this surface “cleaned” so that the bacteria then end up in our organism. While most of the bacteria identified by German researchers are harmless, some – found in small quantities – may be responsible for intestinal infections (Escherichia, Citrobacter, Leclercia). Other studies have also revealed the presence of other pathogenic bacteria such as Escherichia coli (which can, for example, cause diarrhea or food poisoning), Salmonella ( causing salmonellosis ) and Staphylococcus.
The researchers also point out that commercially available cleaners do not eliminate more than 60% of the bacteria found in sponges.
How to guard against these nests with bacteria then? According to the researchers, the simplest is to regularly change its sponges (at least once a week) in order to limit the risks of spread. They also recommend to rinse them with water and the dishwasher after each use, and always to squeeze well ..