Findings from an analysis of smokable hemp products published in Forensic Chemistry indicated that a majority of regulated hemp flower products contain more than the federal legal limit of THC. The study found that 93% of smokable hemp samples contained a mass fraction over 0.3 % tetrahydrocannabinol (THC). The 2018 Farm Bill mandates that cannabis products must contain less than 0.3 percent THC to qualify as legal hemp. The study highlights the need for closer regulation of legal hemp products.
Researchers from the Commerce Department’s National Institute of Standards and Technology (NIST) and the State University of New York (SUNY) Albany analyzed 53 smokable hemp products. The research team used liquid chromatography with photodiode array detection (LC-PDA) method to assess samples from five commercial manufacturers for a range of cannabinoids, such as THCA, delta-8 THC, and delta-9 THC. The researchers took 10-20 grams of each plant sample and ground the flower using a portable Magic Bullet grinder. They then used an extraction method using MeOH (methanol) and recorded cannabinoid levels.
The study compared NIST results to manufacturers’ online documentation and discovered that 22 samples showed levels differed by approximately 18 % for Δ9-THC, 55 % for total Δ9-THC, and 68 % for THCA. About half of the manufacturers’ reports online differed from the corresponding product labels. The researchers attribute the differences between NIST results and manufacturer’s levels to the diverse samples, batch-to-batch variability, and practices impacting harvesting, processing, and storage conditions.
The study also pointed out that storage conditions and degradation could potentially affect THC levels. NIST values were generally higher for Δ9-THC and lower for THCA, which indicates THCA decarboxylation and conversion to Delta 9-THC due to aging.
Sources: Forensic Chemistry, Marijuana Moment