Your kitchen sponge may be dirtier than your toilet.
German researchers conducted a DNA analysis of 14 kitchen sponges. They found more than 350 types of bacteria on them. About one-third of the bacteria were considered not harmful. But some did carry pathogens that could cause infections among humans.
The team notes kitchen sponges are capable of spreading bacteria in places where it was not previously present.
Even if you clean them using the recommended ways, some bacteria will remain. So they recommend replacing your sponges every week.