Stability of nano-emulsified cannabidiol in acidic foods and beverages

Abstract

Introduction: Food and beverage products containing cannabidiol (CBD) is a growing industry, but some CBD products contain Delta(9)-tetrahydrocannabinol (Delta(9)-THC), despite being labeled as "THC-free". As CBD can convert to Delta(9)-THC under acidic conditions, a potential cause is the formation of Delta(9)-THC during storage of acidic CBD products. In this study, we investigated if acidic products (pH <= 4) fortified with CBD would facilitate conversion to THC over a 2-15-month time period. Materials and Methods: Six products, three beverages (lemonade, cola, and sports drink) and three condiments (ketchup, mustard, and hot sauce), were purchased from a local grocery store and fortified with a nano-emulsified CBD isolate (verified as THC-free by testing). The concentrations of CBD and Delta(9)-THC were measured by Gas Chromatography Flame Ionization Detector (GC-FID) and Liquid Chromatography with tandem mass spectrometry (LC-MS/MS), respectively, for up to 15 months at room temperature. Results: Coefficients of variation (CVs) of initial CBD concentrations by GC-FID were <10% for all products except ketchup (18%), showing homogeneity in the fortification. Formation of THC was variable, with the largest amount observed after 15 months in fortified lemonade #2 (3.09 mg Delta(9)-THC/serving) and sports drink #2 (1.18 mg Delta(9)-THC/serving). Both beverages contain citric acid, while cola containing phosphoric acid produced 0.10 mg Delta(9)-THC/serving after 4 months. The importance of the acid type was verified using acid solutions in water. No more than 0.01 mg Delta(9)-THC/serving was observed with the condiments after 4 months. Discussion: Conversion of CBD to THC can occur in some acidic food products when those products are stored at room temperature. Therefore, despite purchasing beverages manufactured with a THC-free nano-emulsified form of CBD, consumers might be at some risk of unknowingly ingesting small amounts of THC. The results indicate that up to 3 mg Delta(9)-THC from conversion can be present in a serving of CBD-lemonade. Based on the previous studies, 3 mg Delta(9)-THC might produce a positive urine sample (>= 15 ng/mL THC carboxylic acid) in some individuals. Conclusion: Consumers must exert caution when consuming products with an acidic pH (<= 4) that suggests that they are "THC-Free," because consumption might lead to positive drug tests or, in the case of multiple doses, intoxication.