1. The kitchen sponge
Believe it or not, many people overlook the kitchen sponge, primarily because it is a cleaner itself. But did you know that this all-purpose kitchen item is one of those spots where bacteria love to hide? In order to have a clean sponge, make sure you rinse it after every use. Let it dry outside your sink in a place where it can air out.
I keep mine near the drainboard, and I replace it every two weeks to avoid any salmonella, staphylococcus, or E. coli infestation because it might be too dirty to even wash with it.