Ask Our Experts: Seeking a Breathalyzer for Cannabis

 By J.J. McCoy, Managing Editor for New Frontier Data

Q: Is it true that someone has invented a breathalyzer for cannabis? How would that work?

A: There have been some recent reports touting breakthrough breathalyzer technology, though testing thus far has been limited to competition trying to develop (and market) the technology for law enforcement, employer, and insurance applications. But the proverbial jury remains out, and perhaps irretrievably so.

Hound Labs has been working on such technology since 2014. According to the Oakland, Calif.-based company, its prototype (priced around $5,000) takes data from the deep lungs to detect a pass/fail presence, as opposed to how a standard alcohol breathalyzer measures one’s blood alcohol content (BAC) reading.

In 2019, six months before raising $30 million in Series-D financing led by Intrinsic Capital Partners, the company announced trial showing that its machine could detect THC in a consumer’s breath (to the minuscule amount of a trillionth of a gram per liter) for up to two or three hours after inhaling.

Recently, Oklahoma’s legislature authorized a $300,000 pilot program for its Department of Public Safety (DPS) to test the device. Legislators say that under the pilot program, participation will be voluntary, and inadmissible in a court of law while the DPS distributes units among both rural and urban law enforcement officers. Oklahoma’s current law requires only testing for alcohol by use of a breathalyzer. The DPS expects it may take a year to establish the parameters of the program before field tests begin. House Bill 4161 awaits Gov. Kevin Stitt’s signature.

Also in May, UCLA chemists reported discovering a key chemical necessary to devise a small, electronic breathalyzer for cannabis detection. Through their published research in a peer-reviewed journal of the American Chemical Society, the chemists claim to have established a “fundamental proof of concept” for technology, though not any actual device ready to compare or compete against the Hound Labs model.

Yet to be answered through either announcement, however, is whether any breathalyzer will be able to distinguish between intoxication versus mere consumption by an individual.

A report by the Congressional Research Service released last year concluded that, “based on current knowledge and enforcement capabilities, it is not possible to articulate a similarly simple level or rate of marijuana consumption and a corresponding effect on driving ability.”

As New Frontier Data’s Chief Science Adviser Reggie Gaudino (Ph.D. in molecular genetics), points out, the breathalyzer developers “do not mention anywhere the correlation between detection, the oxidation amount, and impairment. And that’s where the rubber hits the road.”

Gaudino explained that detecting a response to alcohol is straightforward in terms of body weight and how alcohol works in the system to predict impairment. “One’s response to alcohol is a fairly simple linear model based on a combination of body mass and ability to process alcohol, which is in part controlled by a much simpler set of genetics that the endocannabinoid system.”

He added that “what is not the same in cannabis are what are known as their entourage chemicals, and their mediating effects on impairment. Each person has an endocannabinoid system that is multigenic. There are at least five known cannabinoid receptors, and maybe more because the potential number of independent genetic backgrounds is large, and other chemicals mediate the experience and ‘functional impairment’ levels, and you cannot assume a linear relationship like alcohol, so there is no way to know that someone will be as impaired as another or even past ‘function’ without extensive additional studies on many different genetic backgrounds.”

Ultimately, then, practical outcomes may hinge on matters of political expediency over scientific evidence.

If a rush to sell products and decide policy wind up leading marketers and lawmakers to “wave their hands, shrug their shoulders, and claim that it’s all the same and none of that matters,” Gaudino warns.

“They will shove out something that gives a large number of false positives, but with no data on one’s personal experience and whether every variety will result in the same level of functional impairment,” he said. “Alcohol has a predictable level of functional impairment that is directly correlated to one’s body mass, and further affected by one’s ethnicity. This is about measuring functional impairment, not whether or not someone recently consumed cannabis.”

In an industry long afflicted by false biases and systemic injustice, the prospects for introducing new false biases offer no breakthrough at all.