In an ongoing effort to make a reliable roadside test to check if a driver has recently used cannabis, the federal government will spend more than $1.4 million to study how the concentration of cannabis components in people’s breath changes over time after use.
In a short “sources sought” notice posted last week, the nonregulatory U.S. government agency National Institute of Science and Technology (NIST) said it is looking for a vendor who can help with a study that would collect breath and blood samples and then test them for signs of recent cannabis use, such as delta-9 THC, other cannabinoids, and their metabolites.
“NIST intends to seek a contractor that will recruit participants to the study, collect breath samples from them after they consume their own legal-market marijuana, and send those samples to NIST for laboratory analysis,” Richard Press, the agency’s acting director of media relations, said in an email to Marijuana Moment. “The purpose of the sources sought notice is to tell potential vendors what the requirements are.”
Even though many people have tried to make a device that works like a breathalyser for alcohol over the past ten years, there is still no widely accepted way to tell if someone has recently used cannabis.
“Cannabis/marijuana use is legal all over the country, and it is known that it can impair the thinking skills needed to drive. We need roadside equipment that can tell if a driver is impaired by marijuana right away.”
The next study, titled Breath Measurements of Acute Cannabis Elimination (BACE), would examine “how the concentration of cannabis chemicals on a person’s breath changes in the hours following marijuana use,” according to the press. The study will only measure concentrations of chemicals in breath, not impairment.
The notification states that baseline and experimental samples will be taken from participants before and frequently after they consume cannabis. The measurements are meant to take into account the fact that some people who use cannabis can still have THC on their breath even after quitting.
The project’s funding description states, “To overcome the difficulties of establishing recent cannabis usage from a single breath sample, we suggest a paradigm shift: two breath samples separated by a brief interval.” “A slope compatible with acute cannabis elimination would differentiate recent cannabis use from abstinence.”
The data will be utilised by NIST to investigate the viability of a two-point roadside measurement. This research could lead to a roadside method for detecting recent cannabis use and enhancing public safety.
Is Blood THC levels and Impairment Related to each other?
According to the description, there is no link between blood levels of delta-9-terahydrocannabinol (9THC) and being unable to drive.
“We propose to collect breath samples from occasional and frequent cannabis users at 10-minute intervals during acute cannabis elimination, similar to the previous work, and during periods of abstinence, which has not been examined. The proposed paradigm shift depends on consistency in the collection of breath samples. Therefore, numerical modelling will characterise the influence of humans (e.g., flowrate and volume) and device factors to improve the reproducibility of aerosol particle collection. We will analyse breath samples for 9THC, its metabolites, and other cannabinoids with high-sensitivity analytical methods. We will employ urine analysis to classify users into occasional and frequent use populations and blood analysis to verify compliance with study protocols. Comprehensive statistical analyses will compare elimination profiles and abstinence profiles with different intervals (e.g., 10 minutes vs. 20 minutes) and will examine the multivariate response.“
The cost of the research is $1.45 million. The $14.4 million budget for forensic science was authorised late last year. In June, members of the House Appropriations Committee expressed concern about drunk driving. They asked officials to continue their efforts to identify and punish drugged drivers.
Due to the difficulty of establishing recent usage, U.S. Representative Earl Blumenauer (D-OR) asked the Department of Transportation in May to modify its cannabis testing laws. Tens of thousands of truckers and other commercial drivers get in trouble for using marijuana, but it’s impossible to know if they smoked days or weeks before being tested.
The lawmaker asked Transportation Secretary Pete Buttigieg to “immediately change the rules about how drivers are tested and how soon they can go back to work.”Due to the difficulty of measuring the amount of cannabis in a person’s system and its effect on driving, data on highway safety and the legalisation of cannabis are being debated.
A study conducted in 2019 revealed that drivers with legal THC levels (two to five nanograms per millilitre of blood) were not statistically more likely to be involved in an accident than non-users. Other research indicates that legalisation may increase road fatalities.
According to self-reported polls, impaired driving declines following laws. In April, RTI International reported that individuals were less likely to operate a motor vehicle within three hours of ingesting cannabis in legal jurisdictions. Another study indicated that auto insurance costs were reduced in places where medical marijuana was approved.
Late last year, President Joe Biden signed a large infrastructure bill that pushed states with legalization laws to educate individuals about impaired driving. Advocates for reducing driving under the influence of cannabis criticized the law, arguing that public education initiatives should not be limited to legal jurisdictions.
Officials have had difficulty conveying their concerns about drunk driving. The NHTSA issued a public service announcement portraying a cheetah smoking marijuana while driving a year ago. Critics deemed it an ineffective effort to discourage such conduct.
In 2020, NHTSA, the Campaign Council, and Vox Creative collaborated on another advertisement that urged motorists not to drive drunk, even if an ax murderer was following them. According to experts and advocates, blood THC levels and impairment are not definitively related.
Separately, the Congressional Research Service found in 2019 that even though marijuana can change a person’s reaction time and motor skills, studies of how it affects a driver’s risk of getting into an accident have shown mixed results, with some studies showing no or only a small increase in risk.