The future of breath test machines – drug testing: A few years ago, a new, and relatively crude device, which consisted of a modified breath alcohol testing machine, was tested to see if it could detect certain substances on the breath. A control group of 47 individuals, who had taken marijuana, cocaine, heroin, and methamphetamines less than 24 hours prior to the test, were tested to check the accuracy of the device. The test detected drugs successfully in 87% of the people tested.
The device required the suspect to breathe into a mouthpiece attached to a micro-particle filter. The microparticles in the breath were separated from the saliva and deposited onto a filter, which was then sealed and stored. The particles were then taken to a lab and tested using liquid chromatography and mass spectroscopy devices. Plans are underway to see if a portable test could be used roadside.
Police, and state and federal highway agencies, are concerned that drugged driving is on the rise, but is not being detected. As marijuana becomes legal in more and more states, the laws are changing to make sure that it is clear that driving under the influence of marijuana is still illegal.
A recent series of studies by the AAA Foundation for Traffic Safety found that DUI fatalities involving drivers who had used marijuana shortly before driving doubled in Washington State after it legalized usage of the drug. Other states have had variance in their statistics, but seem to have an increase after legalization. It seems clear that states need good methods to find drivers under the influence of marijuana that cause accidents which endanger others. The problem is that there’s no reliable and accepted method of measuring levels of marijuana in a driver’s system, other than a blood or urine test. There are also no agreed upon levels of impairment for marijuana, unlike alcohol.
Companies have been developing the equivalent of an alcohol breathalyzer for testing for motorists who are DUI for cannabis. Law enforcement officials have been relying on breathalyzer technology to estimate blood alcohol levels for decades, and the future of breath test machines – drug testing and not just alcohol testing. In addition, there’s a legal agreement to follow the federal government’s definition of what constitutes DUI; all 50 states accept the federal BAC of 0.08 percent or greater as the dividing line.
It isn’t easy when it comes to determining driving under the influence of drugs (DUID) involving marijuana. Police would need a roadside method of measuring levels of cannabis’s main active ingredient, tetrahydrocannabinol (THC), in a driver’s system. There are a few university researchers, and testing companies, all over the world, that are attempting to solve this challenge right now, and market devices for this purpose
But the problem of insufficient scientific research of what levels equal “under the influence” remains. There is no good way of determining what levels of THC in the bloodstream are dangerous, or even whether THC levels are an accurate metric to determine when someone is under the influence of marijuana.
THC Measurement in Drivers
States that have legalized marijuana are having difficulty with the fact that measuring a person’s THC is actually a poor indicator of intoxication. According to Thomas Marcotte, co-director of The Center for Medicinal Cannabis Research at the University of California, San Diego, THC gets stored in your fat cells, and isn’t water-soluble like alcohol. As a result, there isn’t a linear relationship between the amount of THC in the body and impairment.
We are often asked what the legal limit for marijuana is for DUI cases. California has no limit, but Colorado is one state that has a limit. They set the DUI level for cannabis intoxication as five nano-grams of THC per milliliter of blood. But a positive test for the presence of THC only shows that at some point —perhaps a week ago or longer— the person ingested marijuana. The test doesn’t measure the level of intoxication or impairment at all.
Researcher Margaret Haney, a neurobiologist at Columbia University, states that the amount of THC in the body also varies by whether or not the person used cannabis only occasionally (in which case the THC would leave the body quickly) or fairly regularly (in which case it would be stored longer term). The occasional smoker stopped for DUI, could actually be much more intoxicated than a regular user but would have much lower THC levels in their bloodstream.
There is also a difference between consuming cannabis or marijuana edibles, or smoking marijuana. Smokers almost always have higher levels in testing.
The AAA, a staunch opponent of DUI, has even admitted that THC levels aren’t effective in determining drivers’ intoxication. It evaluated the arrest records of more than 5,000 drivers arrested for DUI because of their THC levels. It found that
“There is no evidence from the data collected…that any objective threshold exists that established impairment, based on THC concentrations measured in specimens collected from cannabis-positive subjects placed under arrest for impaired driving…. When examining differences in performance in these parameters between subjects with high (>5 2 ng/mL) and low (<5 2 ng/mL) THC concentrations, minimal differences were found. There was no correlation between blood THC concentration and scores on the individual indicators [of intoxication], and performance on the indicators could not reliably assign a subject to the high or low blood THC categories.”
Law enforcement officers would welcome the development of a breathalyzer for marijuana. There are articles online featuring police officers who complaint about the fact that they don’t have this essential tool. But those officials also echo doubts about how accurate such tests could be because of the uncertainty over the effect of THC levels.
The future of breath test machines – drug testing problems. To get around that problem, the developers of breathalyzers for cannabis appear to be focusing on ways to detect the active presence of THC in the bloodstream, which they claim is a better indicator of intoxication.
Cannabix Technologies Inc., a company based in Vancouver, British Columbia, Canada, has been working to bring portable hand-held tools to market that could improve law enforcement’s ability to measure marijuana-impaired driving offenses.
The company has developed drug-testing devices that will detect THC using breath samples. But the company says that it is focused on “developing breath testing devices for detection of recent use of THC, in contrast to urine testing for THC metabolite that requires an invasive collection and reflects use days or even weeks earlier.” They define recent use as within two hours.
Cannabix has been partnering with the University of Florida to develop a THC breath detection device based upon high-field ion mobility and mass spectrometry. Their work is focusing on instant readings of THC through breath. Even they admit that the device only works when people have smoked marijuana, not when they have ingested it in other ways.
Oakland, California-based Hound Labs says that its proprietary technology can measure both smoked marijuana and edibles and can measure the presence of both alcohol and marijuana together. Hound Lab’s breathalyzer can also store breath samples for independent verification at a later date.
Both companies state that their technology will pinpoint those who have used marijuana recently. At the same time, its technology will ensure that unimpaired individuals who may have THC in their saliva or blood because of previous use aren’t wrongfully accused of impairment.
Hound states on their website that the correlation from THC to being “under the influence” shouldn’t stop their device from being used:
“[The] marijuana breathalyzer not only provides information that is immediately useful at the roadside, but also allows ongoing data collection to inform states on how much THC is too much to drive.”
Clinical trials started at the University of California, San Francisco, in May 2017, and the first data from those trials and testing are expected to be published late this year or early next year.
The future of breath test machines – drug testing in the future for DUI. The controversy over whether breath devices are accurate and effective for drug testing will certainly continue for much longer, as DUI defense attorneys for clients accused of marijuana DUI are likely to challenge the results of those breathalyzers and the use of THC as a measure of intoxication.