February 2, 2022
Abstract appeared in PubMed
Purpose: Cannabidiol products remains largely unregulated in the US. Unlike the Rx formulation of CBD [EpidiolexR], little information is available regarding labeling accuracy (does the product contain what the label says it does), lot to lot variability, nor long-term product stability.
Understanding these properties are fundamental if these products are to be used in patients with epilepsy, where product variability of traditional AEDs has been suspected to result in inadequate seizure control.
Therefore, we analyzed commercial CBD products, including oils, aqueous products (i.e., beverages), and various Other products for cannabinoid content vs label claims and stability under United States Pharmacopeia (USP) standards.
Method: Samples were diluted and analyzed by HPLC for CBD, THC, and CBN concentrations in order to assess product label accuracy. Products with <90% of label claim CBD were denoted over-labeled, products with >110% of label claim CBD were denoted under-labeled, and products between 90% and 110% of label claim CBD were denoted appropriately labeled, per USP standards.
Results: Among commercial CBD Oils (n?=?11), mean CBD concentration vs label claim was 91.56% [95% CI, 66.02–117.10%], although 18.18% of oils (n?=?2) made nonspecific label claims of “hemp extract” in lieu of CBD. Among all oils, 36.36% (n?=?4) were appropriately labeled, another 36.4% (n?=?4) of all oils were under-labeled, maximum 128.3% label claim, and finally, 9.09% (n?=?1) of oils were over-labeled. The remaining 18.18% (n?=?2) of oils lacked specific CBD label claims, minimum of 0.3?mg CBD per 1-ml “dose”. THC was detected in 54.55% (n?=?6) of oils with a maximum concentration of 0.2% w/v and a minimum concentration of 0.036% w/v. Cannabinol was detectable in only 9.1% (n?=?1) of products at a concentration of 0.00465% w/v.
Among aqueous products (n?=?21) tested, only 66.67% (n?=?14) gave specific CBD label claims, with mean CBD concentration vs label claim of 59.93% [95% CI, 38.24–81.63%]. Only 7.14% (n?=?1) of aqueous products with a label claim were appropriately labeled, 14.29% (n?=?2) were found to be under-labeled, and 78.57% (n?=?11) over-labeled. THC was detected in 23.81% (n?=?5) of aqueous products tested with a maximum THC concentration of 0.0005% w/v, and a minimum concentration of 0.0002% w/v. Cannabinol was detected in 9.52% (n?=?2) of aqueous products, both at a concentration of 0.0015% w/v.
“Other” products (n?=?7) tested ranged from chocolate bars to transdermal patches. Some 42.86% (n?=?3) gave specific CBD label claims, with mean CBD concentration vs label claim of 67.01% [95% CI, 0.87–133.14%]. Among these three “Other” products with specific label claims, 33% (n?=?1) was appropriately labeled, and 66.67% (n?=?2) were over-labeled, with CBD concentrations vs label claim ranging from a minimum of 39.30% to a maximum of 101.99%.
The remaining 57.14% (n?=?5) of “Other” products tested made nonspecific CBD label claims, denoting CBD content in terms of “full spectrum hemp extract” or “activated cannabinoids”. One such product was labeled with a “40–50-mg CBD” range instead of a single, specific value. Tetrahydrocannabinol was detected in 71.43% (n?=?5) of Other products tested with a maximum concentration of 0.0046% w/w, and a minimum concentration of 0.0008% w/w. Cannabinol was detected in 14.3% (n?=?1) of Other products at a concentration of 0.0001% w/w.
Conclusion: We demonstrate that commercial CBD products, especially aqueous beverages, can show inconsistent labeling, vary largely from their label claims should they make them, and show lot-to-lot variability making dosing unpredictable.