Usually, hearing the words “drunk” and “tattoo” in the same sentence is enough to make you wince.

But researchers in California have designed a temporary tattoo that can tell you how drunk you are – and it could help stop people from drink driving.

Scientists at the University of California San Diego (UCSD) have developed a temporary tattoo-style patch made from ordinary tattoo paper fitted with silver electrodes, which creates a five-minute long current. In turn, this triggers a gel strip in the paper laced with a sweat-inducing drug. As the drug seeps into the body through the skin, the wearer will start sweating.

Once the sweat comes into contact with the electrodes, it is able to determine the level of alcohol in the wearer’s system – and then sends the results directly to their smartphone or smartwatch.

According to Business Insider, researchers fitted nine volunteers with the patch before and after they drank alcohol, and found that the tattoos provided an accurate reflection of the alcohol levels in their system. Currently, breathalysers are the most common way of testing whether someone is over the limit, but they have been shown to sometimes be unreliable: both mouthwash and certain prescription medications can sometimes cause people to test as over the limit.

The researchers are now working on a tattoo that could monitor alcohol levels around the clock. In theory, these patches could one day help reduce the number of drink driving-related deaths and injuries, as people would be able to easily see whether they were over the limit before getting behind the wheel – and that can only be a good thing.

Image: iStock

These tattoos tell your smartphone how drunk you are