The stuff people leave on their phones when they touch them can reveal their secrets, scientists in California say. By taking swabs of chemical residues on smartphones and analyzing the molecules, it’s possible to paint a sketch of the phone’s owner’s lifestyle – from diet to medications to locations.
Researchers from the University of California San Diego tested 40 phones, and found traces of everything from caffeine to skin cream to anti-depressants. Because people leave traces of molecules, chemicals and bacteria on the things they touch, it makes profiling more likely. Even washing hands can’t prevent this from happening, the researchers say.
Using a mass spectrometer, the scientists tested 500 samples swabbed from 40 mobile phones and the hands of their owners, the BBC reports. The samples were analyzed then the researchers compared the results to molecules stored in a database to come up with a “lifestyle profile” of every phone owner.
Dr. Amina Bouslimani, an assistant project scientist, says what they found was revealing. She says,
By analyzing the molecules they left behind on their phones, we could tell if a person is likely to be female, uses high-end cosmetics, dyes her hair, drinks coffee, prefers beer over wine, likes spicy food, is being treated for depression, wears sunscreen and bug spray – and therefore likely to spend a lot of time outdoors – all kinds of things.
The majority of these molecules were spread via contact, and even through sweat. Insect repellants and sunscreens apparently lingered for a long time, present months after the person last used such products.
The scientists say this method could identify the owner of an item when there are no fingerprints, can be used to check on medications, and provide information about how much pollution a person is exposed to. It can, of course, be also a highly valuable tool in criminal forensics.
The team is now looking into the varieties of bacteria on human skin, and what they can reveal. Professor Pieter Dorrestein, senior author on the study, says there are at least a thousand different microbes present on a normal person’s skin.
The study was published in the Proceedings of the National Academy of Sciences.