A research team at Washington State University has been developing a breathalyzer that could accurately detect whether a driver is under the influence of marijuana.
Police officers use blood tests to determine if a driver has THC in their system, usually administered at the police station. Blood tests can take up to 24 hours for results.
In Washington state where recreational marijuana is legal, Initiative 502 set the legal limit for 5 nanograms of active THC per mililiter of blood.
Currently, police officers are limited in their choices of reliable portable THC measurement technology in the field. Washington state cops have indicated they would be open to a new portable breathalyzer, but only if it was accurate and reliable.
WSU Chemistry professor Herbert Hill is leading the research team through a second round of testing with the goal of making their marijuana breathalyzer available in 2016.
Hill says the test is designed for immediate accurate results for THC, not the metabolite that is more likely to stay in a person’s system for weeks, and can give false positives.