Modification of AOAC Official Method 2018.11 for Quantification of Cannabinoids in Plant Materials
Overview
Under the current U.S. federal regulations, hemp plant material has to contain no more than 0.3% of Δ9-THC on dry weight basis in order to be considered legal. In addition to the psychoactive Δ9-THC, hemp plant may also contain Δ9-tetrahydrocannabinolic acid (Δ9-THCA), which has no psychotropic activity, but may decarboxylate (e.g., upon heating) to form Δ9-THC. Recent testing guidelines for determination of Δ9-THC concentration in hemp published by the U.S. Department of Agriculture (USDA) require that the used testing methodology must consider the potential conversion of Δ9-THCA into Δ9-THC and the test result reflect the total available THC derived from the sum of the THC and THCA content.
The AOAC International issued a call for methods for quantitation of cannabinoids in plant materials of hemp based on Standard Method Performance Requirements (SMPR) 2019.003. The candidate method had to be able to report concentrations for individual cannabinoids and total THC (sum of Δ9-THC and Δ9-THCA expressed as Δ9-THC) on a dry-weight basis and include a detailed procedure for determination of plant material dry weight.
This poster, presented at AOAC Annual Meeting and Exposition in 2020, summarizes the modifications made to the AOAC Official Method 2018.11 method to address the above requirements. Results of limited precision experiments obtained by the analysis of hemp plant material and calculated on “as is” and dry-weight basis are also presented.
Authors
Lukas Vaclavik, Danielle Houston and Katerina Mastovska of Eurofins Food Integrity & Innovation in Madison, WI USA
