Purdue University and Hemp Biotechnology Company Develop Quantitative THC Field Test

The test will allow law enforcement to detect how much THC is present in a cannabis sample within minutes.

August 21, 2020

While hemp is now federally legal, the inability to distinguish it from its illegal cousin marijuana—cannabis that has more than 0.3% tetrahydrocannabinol (THC)—has posed issues for both law enforcement and hemp industry participants. But a new field test kit may soon change that.

Hemp Synergistics LLC, a Pennsylvania-based hemp biotechnology company, has partnered with Purdue University Northwest to develop a new THC rapid field test kit for law enforcement to distinguish hemp from marijuana in less than five minutes. 

The test, called TRU (THC Recognition Unit), has the ability to measure the amount of THC in a cannabis sample up to 1%. Ron Fazio, a former forensic scientist and the current chief operations officer at Hemp Synergistics, says the test also indicates if the sample contains more than 1% THC, although it cannot detect the specific amount beyond that.

Field test kits exist that can aid in distinguishing hemp from marijuana, but they often need additional lab testing for confirmation. TRU builds off the existing chemistry used for the Duquenois-Levine reagent test, which is a PH test commonly used in the field that simply indicates whether THC is present in the sample. Another test that has been used by law enforcement in Virginia, called the 4-AP test, measures the ratio of cannabidiol (CBD) versus THC to indicate whether the sample is likely hemp or marijuana.

The new test is different because it provides both identification and quantification of delta-9 THC and delta-9 THCA. While it may still require law enforcement to send samples to the lab for additional testing, TRU’s developers estimate it will cut back on that need drastically.

“This product is not designed to replace full forensic laboratory testing—rather, it is designed to give a rapid, accurate field test that can identify what doesn’t need to go to the lab. We estimate it can lower forensic laboratory submittals of suspected marijuana cases by 50 percent,” said Purdue University Northwest’s Christian Westring, Ph.D., who served on the board of directors for the American Society for Crime Laboratory Directors, in a press release.

Leading forensic scientists from Purdue’s newly formed Center for Crime, Forensics, and Security Analysis worked with Hemp Synergistics for more than a year on researching, developing and testing the technology. 

The inability to distinguish between hemp and THC-rich marijuana has led to undue arrests and charges across the U.S., as well as some states banning smokable hemp to avoid the issue altogether.  

Additionally, Westring said the nation’s forensic laboratories, most of which are publicly funded, are often backlogged as a result of the nation's opioid crisis. Routine drug testing can take as long as three months or more, and complex tests, like THC quantitation, can take even longer.

Westring and Fazio say the new technology can quell those issues. Fazio added that this test gives flexibility to states that are not yet under compliance with the Agriculture Improvement Act of 2018 (the 2018 Farm Bill) and have slightly varying allowances of THC content in hemp. Law enforcement agencies will also have the freedom to decide whether they will need to send the samples in for additional lab testing after utilizing the TRU test.

“This test allows them to refine or fine tune their internal policies to meet the expectations of their constituents,” Fazio said. “Having a one-size-fits-all test is pretty neat for us.”

The tests, which cost $14 each, will be ready for distribution in about a month. Fazio said several police departments have expressed interest so far.