Dishcloths are often damp and provide a breeding ground for bacteria and viruses. Since the kitchen towel  is used to clean food, dishcloths are routinely infected with E. coli and salmonella. In 2007 a study from the Journal of Environmental Health found that putting a damp dustcloth (or sponge) in the microwave for 2 minutes killed 99% of living pathogens.[1] However, fire departments have subsequently warned people not to do this as it can be a fire hazard, especially if the dishcloth or sponge is not sufficiently wet. Several small fires have been started as a result of people following the advice from the study.