UC Davis

Following the specified legalization of cannabis products in California, the cannabis industry has quickly grown as new products enter the market and offer various ways for consumers to experience the psychoactive effects of cannabinoids. Edible cannabis products, in particular, have become increasingly popular as they are easily accessible, discreet, and produce a longer-lasting psychoactive effect than smoking cannabis. The Sacramento County District Attorney’s Office Laboratory of Forensic Services does not currently have a validated method for analyzing cannabis edible evidence. The laboratory hopes to add a method for extracting Δ9-THC from edibles to its Controlled Substances Unit’s (CSU) technical manual. For this study, pre-existing Δ9-THC extraction methods from external sources were compiled and evaluated for their effectiveness, extraction cleanliness, and compatibility with the materials available in the CSU. Five procedures were gathered, including a QuEChERS-based extraction, hexane extraction, ethanol extraction, sonication-assisted extraction, and basic/acidic extraction. After initial testing, the basic/acidic extraction produced the greatest extraction cleanliness while being mostly compatible with the available materials. The original method was modified through experimentation with steps involving the base used, number of washes performed, and amount of starting material used. The optimized method was then used to analyze five unknown edibles, and Δ9-THC was successfully detected and identified in all five samples. Overall, this project aimed to develop a robust Δ9-THC extraction method for GC-MS analysis that would utilize the instrumentation, chemical reagents, and solvents readily available in the CSU, increase laboratory testing capabilities, and be reliably applied to casework samples.