Grim but harmless: that's how you might describe the bacteria that lives on your mobile phone.

Long after we’ve sent those texts, checked where we're meeting our friends and called our mothers, these devices retain a biological history of our actions.

Students studying bacteriology at the University of Surrey imprinted their mobile phones onto Petri dishes to see what they might carry.

The results after just three days looked pretty unpleasant, but thankfully most of the bacteria were harmless.

bacteria phone

Bacteria on mobile phone

"Our results show that the mobile phone doesn’t just remember telephone numbers, but also harbours a history of our personal and physical contacts such as other people, soil and other matter,” said Dr Simon Park, senior lecturer in molecular biology, in a statement.

Bacteria can utilise many different things as vectors in order to promote their transmission, with insects, water, food, coughs and sneezes, sexual contact, and rain being just a few examples.

Dr Park added: "Some disease carrying bacteria were occasionally found like Staphylococcus aureus.

“The ecological niche on the body for Staphylococcus aureus is the nostrils, so a furtive pick of the nose, and quick text after, and you end up with this pathogen on your smartphone."

"Each phone tells a story."

bacteria mobile phone