About This Project

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What is the context of this research?

The use, sale, and possession of marijuana (cannabis) in the United States is illegal but the federal government's policy allows states to decriminalize cannabis for recreational use if a regulation system is in place. To date, six states have decriminalized the substance to varying degrees. Sixteen additional states have exemptions specifically for medical cannabis, and nine have both decriminalization and medical laws. In 2012, both Colorado and Washington legalized the recreational use of marijuana. As part of the regulations, the states need to monitor and enforce impaired driving laws in a similar fashion as drunk driving.

What is the significance of this project?

As the number of marijuana users increase with state law changes, it is inevitable that there will be a significant increase in drivers who are “high” either as a result of recreational use or medicinal use. Although all states already have laws against driving under the influence of drugs, there remains a need for a chemical road-side test that validates and supports the current field sobriety test.

The National Highway Transportation Safety Administration (NHTSA) acknowledges the error rate of the officers in the study is close to 50%. In other words, the officers’ ability to detect which subjects were impaired is almost no better than flipping a coin. Therefore, a secondary confirmation of impairment, in a similar fashion as the breathalyzer for alcohol, is clearly needed. This project will result in a reliable and inexpensive device to detect levels of the primary active component in marijuana (tetrahydrocannabinol or THC) in a drivers’ saliva with some precision.

It is well documented that THC rapidly breaks down in the saliva (1-3 hours after smoking) and thus chemical levels accurately correlate to the “high” experienced by users (0.5 – 2 hours). Unlike the standard blood and urine test that are currently used for drug testing, saliva serves as immediate answer biological fluid, is simple to collect and rapidly analyze road-side, and presents little biological hazard to the officers.

As proposed, this device will yield a read-out similar to the pregnancy test, a line illustrating recent use. The display of a line would allow for the officers to arrest the driver and could lead to the standard urine or blood test accepted throughout the judicial system. In addition, such a product, if readily available, may be of valuable use to the general public in states where marijuana is or becomes legal. Having an inexpensive and reliable test could potentially help individuals from letting those under the influence of marijuana engage in unsafe driving.

What are the goals of the project?

Standardize test against current law enforcement methods.

• Design a paper-based test to detect the use of marijuana in saliva samples above a pre-defined threshold as a solid line, analogous to a pregnancy test strip.

• Currently, state standards require the testing of blood, which cannot be obtained by law enforcement without a subpoena, to determine sobriety thresholds. We aim to carry out a a study to compare blood levels of THC with levels in saliva in a pool of at least 25 individuals. This comparison will be an invaluable contribution to the field of forensic science in addition to being a critical element of this project.

• By partnering the THC test with current photo technology in Google Glass, an instant photo of the result can be taken and stored in a possible offenders records.