The 2018 Agricultural Improvement Act redefined “marijuana” to exclude hemp, which was defined as the plant Cannabis sativa L. and its derivatives that contain less than 0.3% Δ⁹-THC ((-)-trans-Δ⁹-tetrahydrocannabinol) by dry weight. Consequently, Americans are purchasing an unprecedented quantity of hemp-derived cannabinoid formulations, many of questionable quality. The majority of hemp-derived CBD (cannabidiol) products, even those marketed as “THC-free”, contain some amount of Δ⁹-THC. The presence of THC in CBD products is an emerging public health concern. The unintended consumption of Δ⁹-THC carries a range of risks including adverse health effects, legal consequences, and possible loss of employment.

The source of Δ⁹-THC in consumer products could result from the isolation of CBD and product formulation or the THC impurities could potentially result from product handling and storage conditions. The intramolecular cyclization of CBD to create the THC skeleton is well-known. This cyclization is catalyzed by Lewis acids or strong protic acids in aprotic organic solvents, often under harsh conditions. However, THC impurities can be formed in both extracted and synthetic CBD when the purified compound is stored in the presence of CO₂ under humid conditions. Presumably, this allows for the formation of carbonic acid (H₂CO₃), which then acts as catalyst for the cyclization into THC.

In this presentation we will present our evaluation of commercial formulations containing CBD exposed to CO₂ in aqueous solution.Quantitation data of CBD and THC by HPLC-UV and UV-Vis in the commercial products before and after sparging with CO₂ will be presented.

Liberty Pelter

Appearances