Intimate details of a person’s lifestyle, shopping habits and health can now be gleaned from the molecules they leave behind on everyday objects such as smartphones, pens or keys, scientists have proven.

US researchers took swabs from the mobile phones of 39 volunteers and used a technique called mass spectrometry to identify individual molecules and compounds on the case and screen.

They then compared them to the Global Natural Product Social Molecular Networking database which records the chemical make-up of thousands of products and drugs to reveal a unique profile of each owner.

The team was able to tell the sex of the owner as well as a host of private information such as whether they were suffering from depression, skin inflammation or allergies, based on medications which were present.

They could also tell whether a person preferred wine or beer, what cosmetics they used, if they dyed their hair or were bald, and if they spent a lot of time outdoors.