Five-minute marijuana test

Cannabis (or marijuana) is a commonly utilized psychoactive drug worldwide. Although recognized for its therapeutic benefits, cannabis raises public health concerns regarding users operating machinery or driving under its influence. Conventional test kits to detect the primary psychoactive ingredient of cannabis, Δ9-tetrahydrocannabinol (THC), have suboptimal analytical capacities, while laboratory-based tests require sophisticated instrumentation, hindering routine, on-site detection.

In a current study published in Science Translational Medicine, investigators from CSB reported the development of a quantitative, dynamic oral fluid test, EPOCH (express probe for on-site cannabis inhalation) that can measure THC concentrations within 5 minutes. EPOCH quantifies oral THC concentrations down to 0.17 ng/mL, which is below the recommended regulatory cutoff of 1 ng/mL. The test is also robust to the consumption of coffee, alcohol, or tobacco and other confounding factors. When applied to oral fluid samples from cannabis users and controls, EPOCH showed excellent detection accuracy by distinguishing the users from the controls. The investigators also demonstrated that THC concentrations fall below the guideline within 12 hours of cannabis smoking, supporting the use of oral THC tests as sensitive means to identify recent cannabis intake.

The investigators envision that the technology can readily be expanded to detect a broader panel of drugs, including opiates, amphetamines, cocaine, and benzodiazepines. It is conceivable to run on-site, multi-panel EPOCH tests from a single saliva specimen to rapidly identify drug types and initiate optimal treatment for overdoses. It would have a range of safety applications: precautionary self-monitoring by drug users, roadside testing by law enforcement, and drug screening in the public sector.