High levels of bacteria have been found in nine out of 10 dishcloths in a survey of Berkshire restaurants.
Nineteen unnamed restaurants in Wokingham were visited by food experts, who took swabs and sent them for analysis as part of a regional survey.
Some dishcloths carried enough food poisoning bacteria to be considered a serious health hazard.
Eight out of 10 taps were also unsatisfactory, while toilet door handles were completely clean.
Now staff are being warned to clean surfaces properly.
Wokingham District Council's senior food safety officer Joanne George said: "Cloths are often responsible for spreading bacteria around a kitchen.
"To stop this happening, they should be cleaned in hot soapy water and dried thoroughly every day."
Samples from Wokingham were part of a bigger survey of restaurants in the South East.
Overall, 44% of surfaces and 75% of dishcloths carried a high number of bacteria including Escherichia Coli, which indicates contact with raw meat or direct faecal contamination.