Forensic scientists at the Midwest Regional Forensic Laboratory, housed at the Anoka County Sheriff’s Office (M.N.), have validated a method to determine the THC quantity of a plant or liquid sample, allowing them to differentiate between hemp and marijuana.
Medical marijuana is legal in the state of Minnesota, but recreational marijuana is not. The state’s Hemp Pilot program allows licensed growers to grow hemp with the caveat that the THC concentration stays below 0.3%. If the level of THC goes above 0.3%, the hemp is considered marijuana, making the growing and selling of it a crime.
However, the forensic laboratory at the Anoka County Sheriff’s Office had no way to decipher if a sample was hemp or marijuana.
“Since a hemp plant and a marijuana plant are the same species of plant, they would yield the same results,” the forensic lab said in a statement. “This made our job difficult as we were unable to determine if an item was from a hemp plant or a marijuana plant with our current methods of testing.”
The new testing method, which went live on March 25, includes a color test in addition to GCMS and HPLC techniques. It gives law enforcement and prosecutors the correct, scientifically valid information they need to either arrest a suspect for illegally possessing marijuana or—just as important—not arrest a suspect if he/she has a hemp product instead.
The method also provides law enforcement important control over the growing industry of hemp-infused products, which includes anything from lotion to sandals. Beside food, there are no national or state regulations regarding the sale of hemp products. Thus, being able to determine purity level in a product, including THC and the popular CBD cannabinoid, gives law enforcement a leg up in the industry.
The Midwest Regional Forensic Laboratory is the first of eight accredited and publicly funded labs in the state of Minnesota to begin quantitative cannabis testing.
Photo: A forensic scientist working at the Midwest Regional Forensic Laboratory. Credit: Midwest Regional Forensic Laboratory