The hemp and CBD market grew faster than the regulatory infrastructure designed to govern it. What emerged was a category with significant consumer interest, minimal enforcement, and a product quality range that spans from rigorously prepared, third-party tested preparations to bottles containing effectively nothing. The published analytical data on this is not anecdotal. It is measured, peer-reviewed, and concerning. A consumer who approaches the hemp market without understanding its integrity problem is likely to draw conclusions from products that do not represent the compound they are trying to evaluate.

What the Analytical Studies Have Found

The most comprehensive published analysis of commercial CBD product accuracy comes from a 2017 study by Bonn-Miller and colleagues, published in JAMA. Researchers purchased 84 CBD products from 31 companies selling online and had them independently analysed by a certified laboratory. The findings were stark: only 31% of products were accurately labelled within 10% of their stated concentration. Twenty-six percent were overlabelled — containing more CBD than claimed, raising concerns about dose consistency. Forty-three percent were underlabelled — containing less CBD than stated, many substantially less. Eighteen of the 84 products contained detectable THC despite labelling that did not disclose it.

A 2019 follow-up analysis by Gurley and colleagues examined a broader sample with similar findings. A 2020 study published in Cannabis and Cannabinoid Research by Lachenmeier and colleagues analysed European CBD products and found comparable rates of mislabelling. Multiple state-level regulatory investigations in the United States — including published reports from Florida, Michigan, and California — have found substantial rates of label inaccuracy in retail hemp products, including products available in health food stores and pharmacies.

The pattern across these independent analyses is consistent: the majority of commercial hemp products do not contain what their labels claim, with underlabelling more common than overlabelling. The scale of inaccuracy ranges from minor to products that contain essentially no detectable cannabinoids despite clear labelling to the contrary.

Why This Happens — The Structural Causes

Understanding why label inaccuracy is so prevalent requires understanding how most hemp products are made. The majority of commercial CBD and hemp products are produced through a supply chain that begins with commodity hemp biomass — grown by contract farmers, extracted at large-scale facilities, and sold as bulk distillate or isolate to product manufacturers who formulate, bottle, and label it. The product manufacturer often has no direct relationship with the farm that grew the hemp, no oversight of the extraction process, and may or may not conduct independent testing before labelling and selling.

At each stage of this supply chain, quality can degrade. Hemp biomass varies in cannabinoid concentration based on genetics, growing conditions, and harvest timing. Extraction efficiency varies based on method and equipment calibration. Distillate and isolate degrade with heat, light, and time in ways that affect potency. Formulation errors in dilution or blending alter the final concentration. Without third-party testing of the finished product — not the raw material, not the extract, but the final labelled product — these errors accumulate invisibly.

Third-party testing itself has quality issues. Not all laboratories that offer cannabinoid testing are equally rigorous. Some operate with equipment calibrated to an insufficient standard, test methods that produce unreliable results, or business models that create incentives to produce favourable results for paying clients. A certificate of analysis is only as meaningful as the laboratory that produced it and the standard to which it was conducted.

What Preparation Method Has to Do With It

The commodity supply chain model described above is not the only way to produce a hemp preparation. A farm-direct, small-batch model — where the same person who grows the hemp also prepares and tests the final product — eliminates most of the quality degradation points inherent in the commodity chain. When there is no supply chain, there is no supply chain failure.

Slow alcohol maceration of whole hemp flower, conducted on-farm, produces a preparation whose cannabinoid concentration is determined by the quality and phytochemical profile of the plant material used, the maceration parameters, and the testing and adjustment process applied to the finished product. Each of these is visible and verifiable. The farm can be documented. The preparation method can be described in specific, checkable terms. The finished product can be tested and the result compared to the label. That comparison is what a certificate of analysis represents when it is conducted by a qualified independent laboratory on the finished product — not the intermediate extract, not the raw material, but the preparation that reaches the consumer.

This is not a claim that farm-direct preparations are automatically superior in phytochemical quality to all commercially produced products — some commercial producers do maintain rigorous standards. It is a structural observation: the farm-direct model eliminates supply chain complexity and therefore eliminates many of the points at which quality can degrade without detection. When one person is responsible for every stage from seed to finished preparation, accountability is not distributed across a supply chain of parties with different incentive structures. It is personal.

What to Look For When Evaluating a Hemp Product

Given the documented state of the market, a consumer evaluating a hemp preparation has a specific set of questions that are more useful than label claims alone.

The first question is whether a certificate of analysis exists for the finished product. Not a COA for the raw extract or the bulk isolate — for the specific product in the specific batch being sold. A COA for the intermediate material tells you nothing about what happened between extraction and the labelled bottle. The finished product COA is the only document that speaks to what is actually present.

The second question is whether the COA comes from an independent, accredited laboratory — one that is ISO 17025 accredited, that tests for a broad panel including cannabinoids, terpenes, pesticides, heavy metals, and microbials, and that has no financial relationship with the brand whose product it is testing. A COA from a laboratory with commercial ties to the producer is not independent verification.

The third question is whether the label concentration matches the COA result within a reasonable margin. Some variation between preparation batches is inherent in small-batch botanical production. Variation beyond approximately 10–15% in either direction on the primary active compound suggests either poor quality control or deliberate mislabelling.

The fourth question is whether the preparation method is described in specific, verifiable terms. "Whole-plant extraction" and "full-spectrum" are terms with no legal definition and no enforcement. A producer who describes their preparation method specifically — the plant variety, the extraction method, the carrier if applicable, the testing and adjustment process — is making checkable claims rather than marketing language. Checkable claims can be evaluated. Marketing language cannot.

The fifth question is whether the producer has a direct relationship with the agricultural source of the hemp. Commodity hemp products are inherently less traceable than farm-direct preparations. A producer who can describe the specific growing conditions, variety, and harvest timing of their source hemp is providing information that bears on phytochemical quality in ways that a commodity supply chain cannot match.

On what this archive is

This article is written by J.P. Hemp Company — a producer of farm-direct hemp preparations. We have a direct interest in the argument that preparation method and supply chain transparency matter. We have tried to make that argument here from published analytical evidence rather than from self-interest, and we have tried to make it in a way that is useful regardless of which producer a reader ultimately chooses. The questions in the final section of this article apply to our products as much as to anyone else's. We publish batch-specific COAs from an ISO-accredited independent laboratory for every preparation we sell. We describe our preparation method in specific terms across multiple pages of this site. We invite the scrutiny this article describes.