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Chemistry published the findings of a University of California-San Francisco study that showed THC could be detected in breath for up to three hours after smoking and that there's a correlation between THC concentrations and blood concentrations for that initial period. The study was sponsored by Oakland, California-based Hound Labs, a venture capital-backed company that has raised $65 million to develop a dual alcohol and THC breathalyzer.
Hound Labs' THC breathalyzer
After a person blows into the handheld Hound device for two minutes, the cartridge is read in a separate bay that acts like a mini mass spectrometer, which can measure the mass and concentration of specific molecules. If THC is detected, the word "warning" will display on the screen. The Hound device is intended to capture and measure tiny particles of THC in human breath to help determine if someone consumed cannabis in the two-to-three hours prior to testing.
"We aren't measuring impairment, we're measuring THC in breath where it lasts a very short period of time, providing objective data about THC in breath to law enforcement and employers to use in conjunction with other information they have gathered," said Hound Labs founder Mike Lynn, an emergency room doctor, reserve deputy sheriff and venture capitalist.
The problems with testing drivers for cannabis
Cannabis compounds, notably THC, don't behave like alcohol does in the body. Alcohol is classified as a depressant that can slow down the nervous system. It's quickly absorbed in the blood and metabolized quickly, according to the
CRS report.
Cannabis has a complex interplay with the body's
endocannabinoid system, and its effects can be either immediate or delayed depending on the form of consumption. THC potency can vary in strains and in products. Hybrid strains can be bred to enhance certain effects such as pain relief, anxiety reduction and muscle spasticity, Morrow said, adding that people can have different reactions to cannabis' effects.
Minimal research exists on how cannabis affects driving. Although some of the most notable cannabis research has occurred
in Israel, there are longstanding complaints that
federal research in the US has been hindered by low-potency and poor-quality cannabis samples.
It's yet to be determined exactly how the hundreds of other compounds in the cannabis plant could potentially affect the testing processes.
Further complicating matters
are attitudes that it's safer to drive while high than it is drunk.
It's been difficult to detect and capture THC in breath, leading to some skepticism about the accuracy of the early stage breathalyzers. A battery of peer-review studies showing the devices in action would go a long way, said Brian Clowers, an associate professor of chemistry at Washington State University.
The elephant in the room remains that the devices do not determine impairment. Someone could conceivably use or consume a small dose without being high, yet still could have THC detected in their breath.
Because pass-fail tests do not prove impairment, that can create problems for patients in the more than 30 US states where cannabis is a legal medicine, said Benton Bodamer, an M&A, private equity and cannabis attorney at Dickinson Wright's office in Columbus, Ohio.
"That's a recipe for a public health disaster," he said. "There's not a pass/fail opioid breathalyzer, so why would some different rules apply in the context of medical cannabis?"
Additionally, even the seemingly tried-and-true drug and alcohol tests
haven't been completely foolproof and some states have tossed driving-under-the-influence convictions for technology failures such as poor calibration.
"Scientific precision requires the absence of bias, for example," he said. "One look at the mass prosecution, conviction, and incarceration of communities of color for simple non-violent drug possession shows how that particular story ends."
And the issue of impairment is not limited to cannabis.
"Anybody who believes you're going to look at alcohol or other drugs in a vacuum is mistaken," said Sheriff Justin Smith, of Larimer County in northern Colorado. Smith said that his office continues to see more incidences in which suspects were under the influence of multiple drugs.
Some polydrug tests have been increasingly adopted following cannabis legalization. That's been the case for healthcare company Abbott's SoToxa rapid mobile drug screening test. The handheld device, which analyzes a saliva sample in five minutes, is being used in Canada, Spain and US states such as Michigan, Alabama and Oklahoma, said Fred Delfino, Abbott's senior law enforcement liaison.
"Because marijuana isn't the only drug that can cause impairment, Abbott has engineered SoToxa to detect if someone has also recently used cocaine, opiates, benzodiazepines, amphetamines, and methamphetamine, in addition to marijuana," he said via email.
Seems like to me if you have enough money for a lawyer you could get out of a cannabis breathalyzer test. I’ve read cannabis levels can be all over the place. Not really all that accurate, I’ve heard with blood testing.
