The ability to detect driver impairment due to marijuana with a simple biologic test similar to the breathalyzers used for alcohol is almost here. The products under investigation are targets for late-night comedians — such as Conan O'Brien spoofing the University of Akron's Cannibuster — but the need is serious.
The state of Washington has had legal recreational marijuana now for two years, and the state recently released its traffic safety data for the years 2010 through 2014. The officials reported the rate of drivers involved in fatal crashes while impaired from cannabis had doubled, while the rate of deadly crashes due to drunk driving have been cut in half since the legalization of marijuana.
Currently, there are no roadside tests that accurately determine impairment to drive related to the consumption of marijuana. When properly administered by trained law enforcement officers, field-sobriety screenings can provide substantial evidence of impairment. However, since these screenings are an observation and a subjective test, they do not always stand up in the judicial system.
The authorization to draw blood samples can take several hours, and this limits their value in documenting a blood level of marijuana. There is a need for an accurate biologic screening tool that would be used roadside at the time a law enforcement officer observes the driver being impaired.
Using saliva or breath to determine the concentration of marijuana in a driver's system and correlating it with blood levels is the strategy of three companies. Cannibuster is described as "a novel, microfluidic device that uses noninvasive saliva testing and lab-on-chip technology to detect THC levels in a matter of minutes." The inventors are two graduate students from the University of Akron — Kathy Stitzlein and Mariam Crow.
Researchers at Washington State University are using the breathalyzer strategy that is more similar to those used to determine impairment related to alcohol. Chemistry professor Herbert Hill, leads the project, which also partners with Chemring Detection Systems. The company will provide the handheld spectrometer technology that is to be attached to the breathalyzer.
The technology measures the impaired driver's breath. The device has undergone a first round of testing, and the hopes are that it will be available for law enforcement to use in the field soon. "For it to be used to help the arresting officer make a decision, I hope is about a year away," Hill said recently.
A third group, Cannabix Technologies, is collaborating with the Yost Research Group at the University of Florida. They are developing a breath analysis device that also utilizes mass spectrometry. The company released images of the device at the Marijuana Investor Summit and Business Expo. The testing with initial prototype is currently underway with the objectives being to maximize sensitivity, detection and reliability.
Those states having the legal use of recreational marijuana are experiencing a public health crisis. The rates of fatalities due to driving under the influence of marijuana are growing, and there are few tools for law enforcement officers to use to remove such drivers from the road. Breathalyzers may prove to be an effective tool.