Δ⁹-Tetrahydrocannabinol Content of Commercially Available Hemp Products

Abstract

Δ⁹-Tetrahydrocannabinol (THC) is the main psychoactive compound present in marijuana. THC can also be found, as a contaminant, in some commercially available hemp products marketed in health food stores and on the internet as a good source of essential fatty acids. The products range from oil to alcoholic beverages to nutritional bars to candies, with oil being the most popular and commonly available. The analytical results are separated into two groups, products tested prior to and after publication of 21 CFR Part 1308, “clarification of listing of tetrahydrocannabinols.” The data presented are a summary of 79 different hemp products tested for THC. THC was separated by a liquid-liquid or solid-liquid extraction, depending upon the product matrix. THC concentrations range from none detected to 117.5 µg THC/g material. Typical limits of detection for the assay (depending on matrix) are 1.0–2.5 µg THC/g material. Products that were of aqueous base (beer, tea) had much lower limits of detection (2.5 ng/mL). No THC was detected in 58% of the products from group 1 and 86% of the products from group 2. The amounts indicate that THC levels in currently marketed hemp products are significantly lower than in those products available before 2003 and reported in previous studies. The results reported here may be used as a general guideline for the THC content of hemp products recently found in the marketplace today.