Legalizing marijuana isn’t just about dropping rules—it’s also about creating new ones. In the US, where over half of US states have now legalized some degree of pot use, one of those new rules requires setting a limit on marijuana intake while driving. That has drawn private tech companies, such as Vancouver’s Cannabix Technologies, to develop a breathalyzer that detects Tetrahydrocannabinol (THC) levels of drivers for police officers to use at the roadside.
Cannabix’s device is in prototype, according to its website. Its founder, retired Canadian police officer Kal Malhi, says the device will be able to detect THC up to two hours after consumption, Reuters reports. Veteran breathalyzer maker Lifeloc—a Colorado-based company that already makes popular alcohol breathalyzers—is also working to develop a THC version of its product.
The first breathalyzer to hit the market will likely ”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,” chief executive of Lifeloc Barry Knott told Reuters. Lifeloc sells its alcohol breathalyzers for $300-$400 a pop, but expects to sell the marijuana version for over $2,500.
A professor-PhD student duo at Washington State University are also in the research and laboratory phase of developing a similar technology, using ion mobile spectrometry, which is also used for explosive and chemical warfare detection.
Developing the technology beyond ‘yes’ or ‘no’ to read specific THC levels might be tricky, given that states already have different legal definitions of ”too stoned to drive.” In Washington and Montana, for instance, it’s five nanograms per milliliter, reports Engadget, while in Pennsylvania, it’s one nanogram per milliliter. Nicholas Lovrich, a political scientist at Washington State University, told Reuters that these limits are more political than based on actual bodily effects.