Temporary Tattoo Tells You When You're Drunk

These days there are plenty of options for those who want to test their (or a friend's) blood alcohol content before getting behind the wheel, but a finger prick is the best bet if what you're after is accuracy. Now researchers at the University of California San Diego are reporting in the journal ACS Sensors that they've developed a temporary electronic tattoo that can induce just enough sweat to get a highly accurate read—which would be sent to a smartphone with an easy-to-interpret app—in minutes. "Such a device hasn't been available until now," engineering professor Patrick Mercier says.

Quartz reports that transdermal bracelets have already been developed to do the same, with SF-based BACtrack winning a $200,000 first prize for developing the prototype, according to IEEE Spectrum. But the wearable device is clunkier and results can take hours, whereas the UCSD device would be not only less bulky but also less pricey. Their system includes a temporary, flexible tattoo that clings to skin and a flexible circuit board smaller than a stick of gum attached to the tattoo via magnets. Readouts on nine test subjects were accurate even after the devices were bent and shaken, so the team is now working on full-day continuous monitoring. For, you know, those big benders. (People might even consider wearing these ... while jogging.)