“The difference between marijuana and hemp is a matter of measurement,” says the National Institute of Standards and Technology (NIST), a physical science laboratory that is part of the U.S. Department of Commerce, on its website.
And yet, taking those measurements to distinguish hemp—defined as having up to 0.3% tetrahydrocannabinol (THC)—and its higher-THC cousin, marijuana, is difficult in the burgeoning industries.
It’s why NIST has launched a program to help laboratories accurately measure key chemical compounds in marijuana, hemp and other cannabis products.
The goal of NIST’s Cannabis Quality Assurance (CannaQAP) program is to help labs produce consistent measurement results, which would both increase accuracy in product labeling and help forensic labs distinguish between hemp and marijuana.
According to a NIST news release, laboratories have limited experience taking cannabinoid measurements, which can lead to unreliable results. This has been a problem especially for cannabidiol (CBD) products, which have been found to contain wildly different cannabinoid contents than what is printed on their labels.
“When you walk into a store or dispensary and see a label that says 10% CBD, you want to know that you can trust that number,” says NIST research chemist Brent Wilson in the news release.
Prior to hemp’s legalization, labs determined if something was marijuana by testing for the presence of THC instead of the concentration, the news release says. Now, this method presents an issue with distinguishing between hemp and marijuana, as hemp may also contain some THC.
One reason measurements vary so much from lab to lab is because there are no reference materials for cannabis, according to the news release. Reference materials come with known measurement values to help labs achieve accurate results.
That’s where the CannQAP program comes in.
How It Works
As part of the program, NIST will send hemp oil samples to participating labs, which will measure the concentration of 17 different cannabinoids and report back to NIST.
After collecting responses, NIST says it plans to publish the measurements the labs obtained. This data will be anonymized so labs cannot be identified, but the aim is to show the variability between results.
NIST will also publish the correct measurements so each lab can see how it performed. In addition, NIST researchers will assess whether some laboratory methods consistently produce better results than others, and if so, they will recommend that labs adopt the better-performing methods.
“Anonymity means that labs don’t have to worry about how their performance will be viewed,” says NIST research chemist Melissa Phillips in the news release. “Our goal is to help labs improve, not to call them out.”
Once the first round is complete, which could take six months to a year, NIST will run a second round of exercises with hopes of seeing a “tightening of numbers.”
The lab says it plans on expanding to include plant material in the future and measure a larger number of compounds, including terpenes and contaminants. NIST is also working on developing a hemp reference material to serve as a baseline of measurement for labs.
“Labs can accurately measure how much sugar is in your orange juice because they have standardized methods and reference materials for that type of product,” says Susan Audino, a chemistry consultant and science adviser to the Cannabis Analytical Science Program of the AOAC International, a group that establishes standard methods for laboratory analysis. “But cannabis has been a Schedule I drug since the ‘70s,” she said, referring to the Drug Enforcement Administration’s designation for drugs that have the highest potential for abuse.Laboratories that are interested in participating in CannaQAP can register online. Registration in the first exercise involving hemp oil will be open through Aug. 31