(TDB) - A San Francisco-based tech company has won a $200,000 prize for its wearable alcohol monitor capable of detecting a person’s blood alcohol levels and alerting a user when they should stop drinking.

BACtrack, a privately held medical device maker, won the cash prize in the National Institutes of Health Wearable Biosensor Challenge on Thursday for its BACtrack Skyn wristband.

The wearable device measures blood alcohol content (BAC) via sweat on the skin. It connects to a smartphone via bluetooth technology, allowing the user to track their alcohol intake, even alerting the user’s phone when they are drinking too much.

The Wearable Alcohol Biosensor Challenge kicked off in March as way of encouraging discreet wearables that improve on the current approaches to measuring blood alcohol content (BAC).

The challenge called for non-invasive wearable technology that could improve upon existing alcohol biosensor technology, such as breathalysers, used in the criminal justice system. An improved alcohol biosensor could be a valuable resource for the alcohol research community, decreasing reliance on participant self-report in scientific studies.

Medical, law enforcement and transportation officials have long sought better technology for detection of blood alcohol levels, with

Traditional portable breath alcohol testers (PBTs) used by medical, law enforcement and transport officials are bulky, expensive and incapable of providing ongoing monitoring of alcohol levels. The purpose of the challenge was to help uncover alternative solutions.

However the BACtrack Skyn device is still not yet a suitable substitute for breathalyzers or blood tests used by law enforcement, as it is not able to provide real-time blood-alcohol levels