Quantification of Cannabis in Infused Consumer Products and Their Residues on Skin

Cannabis consumer products are a $4.6 billion industry in the U.S. that is projected to exceed $14 billion by 2025. Despite an absence of U.S. Food and Drug Administration (FDA) regulation or clinical data, thousands of nutraceuticals, topical consumer products, and beauty products claim benefits of hemp or cannabidiol. However, a lack of required quality control measures prevents consumers from knowing the true concentration or purities of cannabis-labeled products. Thirteen over-the-counter consumer products were examined for the presence of cannabidiol (CBD), cannabinol (CBN), Δ⁹-tetrahydrocannabinol (THC), cannabidiolic acid (CBDA), and Δ⁹-tetrahydrocannabinolic acid A (THCA). Additionally, the efficacy of topical applications was investigated using a porcine skin model, in which particle size and zeta potential relate to skin permeability. Skin permeation was correlated to particle size and relative stability in skin-like conditions but not directly related to the CBD content, suggesting that topical products can be designed to enhance overall skin permeation. Of the products analyzed, all products have some traceable amount of cannabinoids, while seven products had multiple cannabinoids with quantifiable amounts. Overall, the need for further regulation is clear, as most products have apparent distinctions between their true and labeled contents.