It seems bizarre that the dirtiest item in your kitchen is the one you’re using to clean other surfaces, but a recent survey of U.S. homes conducted by the National Sanitation Foundation confirmed just that.
After testing sponges and dishcloths in 22 homes, the NSF found that 77 percent contained coliform bacteria (a sign of fecal contamination), 86 percent were infected with yeast and mold, and 18 percent had traces of Staphylococcus (bacteria that can cause diarrhea and vomiting). Replace your dishrag daily or pop a damp sponge in the microwave on high for one minute to properly disinfect.