One in six UK mobile phones are contaminated with faecal bacteria due to poor personal hygiene, scientists have found.
Researchers said that 16% of the devices were contaminated with E coli, which can cause food poisoning, most probably because people fail to properly wash their hands after going to the toilet.
The study by the London School of Hygiene and Tropical Medicine and Queen Mary, University of London, also found that Britons tend to lie about their personal hygiene.
While 95% of the 390 people surveyed said they washed their hands with soap where possible, 92% of mobile phones and 82% of hands were contaminated with bacteria.
The study, which took samples from 390 phones in 12 cities, raises serious public health concerns as it found that 16% of hands and the same proportion of phones were contaminated with E coli. A virulent strain of the bacterium has recently been implicated in the fatal outbreak of food poisoning in Germany in June.
Dr Val Curtis, from the London School of Hygiene and Tropical Medicine, said: "This study provides more evidence that some people still don't wash their hands properly, especially after going to the toilet.
"I hope the thought of having E coli on their hands and phones encourages them to take more care in the bathroom - washing your hands with soap is such a simple thing to do but there is no doubt it saves lives."
The scientists also found those who had bacteria on their hands were three times as likely to have bacteria on their phone.Dr Ron Cutler, of Queen Mary, University of London, said: "While some cities did much better than others, the fact that E coli was present on phones and hands in every location shows this is a nationwide problem. "People may claim they wash their hands regularly but the science shows otherwise."