Law enforcement officials have had difficulty determining if a driver is impaired from marijuana. This issue sparked interest for several companies to begin developing a marijuana breathalyzer to detect THC levels. Arguments have surrounded the projects because it is difficult to determine the level of impairment based upon THC level, as each person reacts to marijuana differently.
For law enforcement officials in Washington State, detecting THC impairment is quite a process, according to Bloomberg.com. Experts must be called in to run specific field sobriety tests and a warrant must be obtained to request a blood sample from the suspected impaired driver. This is an inefficient system as THC metabolizes in the blood and performing the test can take hours to complete, reducing the THC level in the bloodstream.
Herb Hill, who has been commissioned to build a marijuana breathalyzer says, “It’s an interesting project to end on, and an important one. I haven’t seen anybody who has determined how that relates to being impaired.”
Hill’s first thoughts regarding the breathalyzer machines for detecting drug-induced impairment were in 2009. For this venture, Hill has reportedly raised $300,000 in funding from an overseas British defense group, Chemring Group. The group has a contract with U.S. entities for building such devices.
The process being tested is called differential mobility spectrometry (DMS). It creates two electric fields that maintain flow to THC ions, sending them to sensors near the end of a testing tube. The process is supposed to allow THC to flow through the tube but keep the additional ions out for accurate THC level readings.
Study leaders tested theories of attempts to cover up THC on the breath with food and beverages. The test still allowed THC to come through. To gain participants, marijuana users were compensated for their time, which had to be made clear to make the process legal.
Each volunteer was paid a sum of $10 to have their breath tested both before and after using marijuana. Some volunteers were compensated an additional fee for making a special trip to a dispensary for the study. All participants used the same strain, Blue Dream.
Initial study results returned analysis that 81-percent of the samples collected contained varying levels of THC. Additional studies regarding the effect of THC on one’s ability to drive are still pending.