Scientists Develop Quick Test for Marijuana Use

In an early study, scientists found that their rapid test was able to reliably detect THC in people’s saliva in under 5 minutes. THC, short for tetrahydrocannabinol, is the active ingredient in marijuana.

Right now, the “gold standard” for detecting marijuana use is to measure THC in the blood or urine. But those tests can take days to process. The other drawback is that unlike alcohol, THC can linger in the bloodstream for days or even weeks — so a “positive” blood test does not necessarily reflect recent use.

Those facts have made it hard to develop a roadside test for marijuana use, akin to the Breathalyzer used to measure drivers’ alcohol levels.

THC in saliva, however, reflects marijuana use within the past 12 hours, said Hakho Lee, the senior researcher on the new study.

There are some existing saliva tests for THC, but they are hampered by issues like slow processing time or giving “binary” results — similar to a yes/no on a pregnancy test.

Lee said his team was able to develop a test that not only quickly detects THC in saliva, but quantifies the amount.

In initial testing with 43 marijuana users and 43 non-users, it accurately picked up THC in saliva samples from all users of the drug. [Read More @ USNews.com]