A marijuana breathalyzer is one step closer on its road to commercialization.

Hound Labs Inc., an Oakland startup founded in part by an ER doc/reserve deputy sheriff and a patent attorney, on Tuesday announced that its handheld device that measures the presence of THC in breath successfully completed roadside field testing by law enforcement officers. The device — which was developed in partnership with scientists at the University of California-Berkeley was designed to detect impairment from recent THC consumption via smoking pot or ingesting edibles, Reuters and others have reported.

On Tuesday, Hound Labs’ CEO Dr. Mike Lynn chatted with The Cannabist to give an update on Hound Labs and the next steps for the marijuana breathalyzer.

What the roadside tests entailed

Hound Labs’ devices — similar in size to alcohol breathalyzers — were used in situations in which an officer suspected marijuana use or if the driver admitted to recent marijuana use. If the drivers performed poorly in the field sobriety tests, they were asked if they would voluntarily blow into the handheld device, which relayed the information to the docking station to conduct the chemical analysis.

“We were not trying to arrest people,” Lynn said. “To be very specific, we were trying to educate people about (how) it’s illegal to drive stoned.”

The readings of THC levels in the breath did correlate to how recently the driver consumed marijuana, Lynn said. Drivers that failed the roadside tests were not arrested but were found a safe means home.

The only major modification required after testing will come in the product design, he said, adding that the company is now working to make the handheld device more rugged and durable.

Lynn declined to disclose which departments conducted the roadside tests, citing confidentiality concerns, but said the company soon will start tests with the Lompoc, Calif., police department.

“We’re going to be doing a lot more of that testing in the near future,” Lynn said.

The testing of breath, as opposed to saliva

Some of the other companies and entities developing instruments to measure THC impairment in drivers use saliva. In Colorado, the state patrol is testing five devices as part of its marijuana oral fluid pilot program.

At Stanford University, researchers are developing a “potalyzer” to detect the presence of THC in saliva. Stanford researchers have demonstrated proof of concept, and the next step is to conduct tests in humans, said Tyler O’Brien Shultz, a member of the research team.

Lynn believes the advantage to testing in breath is because THC has been shown to remain present in breath for a couple of hours. The test would correlate to recent consumption and impairment as opposed to the detection of THC’s longer-lasting presence in the bloodstream.

“It prevents the unfair arrests of people who have every right to smoke as long as they don’t get behind the wheel,” Lynn said.

But the breath approach isn’t without its critics. Carl Hart, a Columbia University professor of psychology and psychiatry conveyed skepticism to the Atlantic, claiming that “what’s in the breath probably doesn’t represent what’s in the brain.”

What’s next

Lynn said the results from the field tests were reassuring — the readings correlated to the time frames when the drivers said they last consumed — but Hound Labs will continue on its path to conduct more field trials, conduct the clinical trials and amass even more data.

“It does allow us to be part of the regulatory changes that will occur down the line as the measured level starts to be correlated to actual driving impairment,” he said.

It’s a balance between safety and fairness, he said.

“It’s really that combination of making sure we get the right people off the road and, at the same time, not arresting people that aren’t impaired,” he said.

As its lab work progresses, Hound Labs plans to raise additional funding to ready the company for commercialization and a targeted product launch in the second half of 2017. Hound Labs has raised $4 million since its founding in 2014, company officials said.

The breathalyzer will be priced under $1,000, and similarly to alcohol breathalyzers, Lynn said.

“It’s really a balance between safety and fairness,” he said.