Soon, you may be able to check your blood alcohol level just by looking at your phone. Engineers at the University of California San Diego have designed a temporary tattoo–style sensor that sticks on the skin and measures blood alcohol levels in sweat, as Broadly reports.

The study, published in ACS Sensors, was just a proof-of-concept, and tested only nine drinkers in the lab. They drank 12 ounces of beer or 5 ounces of wine while wearing the sensor tattoo on their arm, waiting 10 minutes for the alcohol to pass into their bloodstream. The sensor was successful at detecting whether or not the volunteers had alcohol in their system. It is also equipped with a Bluetooth sensor, designed to beam the wearer’s blood alcohol content to an app, helping people track their drinking in real-time. 

By measuring blood alcohol content (BAC) and making the data accessible by an app, the tattoos could help people verify that, yes, they really are too drunk to drive home. Drunk people don’t have the best judgment, and everyone’s body is a little different, so it can be hard to tell exactly how intoxicated someone is. As the researchers found with their volunteers, drinking the same amount of alcohol doesn’t result in the same BAC in different people: 

Even though three subjects consumed the same amount of alcohol, their BAC values measured by breathalyzer vary due to their different alcohol metabolism rates and body weights. For example, three subjects in [showed] 0.022 percent, 0.017 percent, and 0.026 percent BAC, respectively, after consuming the same amount of alcohol.

This would give you the cold, refreshing data. 

The device sounds like a pretty good way for college students to monitor whether they (or their friends) are having an epic night, or need to get to a hospital ASAP. Furthermore, it could be a more accurate way to test for drunk drivers, since breathalyzer results used by police during traffic stops are notoriously flawed. However, since this was such a small study, these tattoos are a long way from hitting a party near you. 

[h/t Broadly]

All images courtesy UC San Diego Jacobs School of Engineering via Flickr

Know of something you think we should cover? Email us at tips@mentalfloss.com.