A California company said it has created the first marijuana breathalyzer test, which has the potential to be used by police to detect whether drivers have used the drug.

As more states legalize marijuana for recreational and medical use, law enforcement officials have grown increasingly concerned about individuals driving while high. Until now, police officers in the U.S. did not have any roadside means to determine whether a driver had consumed cannabis.

They have depended mostly on field sobriety tests developed to catch alcohol use, or on personal observation, which is subject to deception. But Oakland-based Hound Labs wants to make testing for marijuana as easy as testing for alcohol.

“We are trying to make the establishment of impairment around marijuana rational and to balance fairness and safety,” CEO Mike Lynn told NPR, explaining that his company has created a breath test to detect THC, the principal psychoactive ingredient in cannabis

“This is a disposable cartridge. And there’s a whole bunch of science in this cartridge,” Lynn explained to NPR, showing the reporter the product. The company says the cartridge can detect marijuana use within the past two hours, which many experts consider the peak time for the full effects of THC to kick in. [Read more at Newsweek]