The National Highway Traffic Safety Administration, in a paper this year, said cannabis impairs psychomotor skills, attention, lane tracking and cognitive function, but not enough is known about how much is needed to affect driving performance.
A roadside breathalyzer would replace a complicated assortment of costly blood and urine tests that can take days to get a result. But even these tests are a long way from showing impairment, as the science on how cannabis affects driving is far from settled.
As cannabis bans are relaxed in more U.S. states, the race is on to develop an instant roadside breathalyzer for police to test drivers who may be taking the “high” road. Vancouver-based Cannabix Technologies Inc, founded by a retired Royal Canadian Mounted Police officer, expects to be first out of the gate with a “pot breathalyzer” – a handheld device similar to those used to detect alcohol. Cannabix won’t give an estimate of when its product might go on sale, but has a prototype undergoing in-house testing. Other hopefuls, such as Colorado-based Lifeloc Technologies Inc and a chemistry professor-PhD student duo at Washington State University, are still busy in the lab. The devices aim to accurately detect the presence of THC, the psychoactive component in cannabis, but can’t provide enough evidence of impairment by themselves. “I think the first breathalyzer on the market will be a simple ‘yes’ or ‘no’ for the presence of THC at the time of the test, and in that sense it won’t provide a quantitative evidential measure,” said Barry Knott, the chief executive of Lifeloc, which already makes alcohol breathalyzers. The size of the potential market is unclear, owing to widely varying estimates of cannabis use, and unreliable data on those driving under its influence. But developers say they will be able to sell pot devices for a lot more than the ubiquitous alcohol breathalyzers. Lifeloc sells alcohol breathalyzers for $300-$400 but expects to charge $2,500-$3,500 for its cannabis version. Marijuana is illegal under U.S. federal law but is allowed for medical use in about half the country’s states. Others, including Oregon and Colorado, have gone further, allowing recreational use. Lifeloc shares, traded over the counter, have risen about 21 percent to $14.50 this year, while Cannabix’s have risen about 21 percent to 17 […]