An analysis published in 2024 in Frontiers in Pharmacology evaluated 202 CBD products, revealing that 74% deviated from their stated potency by at least 10%, with discrepancies occurring both above and below the declared levels. Additionally, 26% of the products did not conform to the basic product type definition on their packaging, highlighting a market where labels are unreliable indicators of actual dosage.
The product sample included 100 tinctures, 48 gummies, 34 vape products, and 20 topical applications. Potency errors and contamination profiles varied across these formats.
Contaminant And Potency Findings
The analysis also checked for contaminants, finding heavy metals in 44 of the 202 products. Residual solvents were present in 181 samples, and pesticide screening detected 26 different compounds in 30 products, suggesting cultivation practices as the source.
Hemp effectively absorbs metals and other soil residues, making cultivation inputs critical for the purity of the final product. Extraction introduces additional exposure risks; solvent-based methods can leave traces if the purge process is rushed or equipment is poorly maintained, leading to concentrated residues in distillates used for tinctures or gummies.
Finished-goods testing can identify issues missed during raw-material testing, as contamination can occur at any stage from harvest to packaging. Brands that only test incoming biomass may verify the cheapest supply chain input but leave the final product unchecked.
This is not a new issue. Previous testing of 84 over-the-counter CBD products showed only 31% were accurately labeled within 10% of their advertised content. A National Institutes of Health study found similar discrepancies, with 26% of products containing less CBD than stated and 43% containing more. This measurement problem has persisted for nearly a decade, prompting regulators to require current certificates as essential proof rather than optional.
The error size varies by format. Tinctures rely on even suspension in carrier oil, so separation during storage may result in different dosages from top to bottom. Gummies depend on even distribution before setting, meaning individual units can deviate significantly from the batch average even if the batch tests correctly. Testing a composite of 10 gummies obscures the variation customers may experience.
Potency errors are significant because CBD is an active compound. An FDA-funded trial administered twice-daily CBD to healthy adults for 28 days, noting elevated hepatic aminotransferase levels in some participants. Reported adverse effects included increased hepatic enzymes in 11% of participants, eosinophilia in 9%, somnolence in 8%, and diarrhea in 8%. These elevations reversed after discontinuing dosage, with no severe adverse events, though the findings were substantial enough to warrant publication.
CBD inhibits several cytochrome P450 enzymes, affecting how the liver processes many common medications. A product containing 40% more CBD than labeled could unintentionally alter a dose, undetectable to the prescribing physician, for someone taking a blood thinner or anticonvulsant.
Accurate labeling is crucial for consumer safety. Customers relying on printed serving sizes depend on laboratory validation to ensure accuracy.
Federal Enforcement And Label Language
Since 2019, the FDA has issued over 200 warning letters to cannabinoid companies. In April 2025, the agency’s Center for Veterinary Medicine wrote to Bailey’s Wellness, Holista, and House of Alchemy regarding unapproved cannabis-derived products marketed for uses the FDA had not evaluated. These letters often address both marketing language and manufacturing practices.
This approach is intentional. A therapeutic claim transforms a supplement into an unapproved drug under the Food, Drug, and Cosmetic Act, altering the manufacturing standards the agency enforces. Companies avoiding disease claims remain within regulatory categories their quality systems can meet.
The Second Audience For Test Results
Certificates of analysis are reviewed beyond factories. Underwriters require them alongside licenses and product catalogs for new accounts, and firms managing CBD payment volumes consider them as indicators of operational discipline. Well-organized lab records help reviewers find necessary information without additional requests.
Retailers and insurers conduct similar evaluations before assuming liability. They require evidence that product contents match labels, relying on documentation from established lab programs.
How To Build A Testing Program For Regulatory Review
Each production lot requires its own certificate of analysis, linked to a lot number on the package and issued by a laboratory accredited to ISO 17025. Composite testing across multiple lots conceals variations that testing aims to reveal.
The testing panel should include cannabinoid potency, residual solvents, heavy metals, pesticides, microbials, and mycotoxins. Retention samples from each lot enable re-testing if complaints arise months after sale. Publishing certificates with a lot-number index allows customers to verify unit contents.
Qualified suppliers are essential. Purchasing distillate on the open market means assuming the cultivation practices used. Independent tests commissioned by brands provide stronger evidence than seller-provided certificates. Qualified suppliers agree to periodic audits and contractual specifications with rejection rights.
Logged complaints tracked to lot numbers enable brands to retrieve retention samples and trace issues to their sources quickly. This speed determines how much inventory must be destroyed and how many customers are affected before the issue is resolved.
The Cost Of A Failed Batch
A contaminated or mislabeled batch is rarely contained. Product recalls start with inventory destruction and laboratory work to determine the problem’s extent. The larger cost follows when the acquiring bank reviews the account, the retailer suspends the item pending re-qualification, and the insurer adjusts the product liability policy. Each party reaches the same conclusion from the same document set, and the decisions are not easily reversed.
The FDA clearly states it has never reviewed the manufacturing of unapproved CBD drug products, and the effects of consuming products with unsafe pesticide or heavy metal levels remain unknown. This message appears in agency materials for consumers and risk memoranda used by institutions deciding the duration of a CBD merchant’s account.
Full-panel testing for every lot costs operations several hundred dollars per batch. The subsequent costs are what potentially drive companies out of business.

