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Lab Results Over 100% Purity

Over the last several years, ultra-purified CBD products have increased in popularity and become an integral part of the CBD manufacturing supply chain. Prior to going to market, these products are tested and can sometimes have CBD results over 100% purity.

This has led to the question:

“How can the purity of my product be over 100%?”.

Seeing lab results over 100% purity can be very confusing for not only CBD manufacturers, but also for the end user. Before we answer how this can be possible, we would like to present some background information that will help explain this normal scientific occurrence.

Brief History

Historically, chemical compounds with 100% purity were only accessed by professionals in scientific communities. Products manufactured to 100% purity and offered as consumer goods and products has been very limited prior to the inception of crystalline forms of cannabinoids. Not even 190 proof grain alcohol on the shelves of your local liquor store is 100% ethanol. Rather, products are manufactured to a target value with a percentage of uncertainty around that target.

While still in its infancy, high-purity cannabinoid products might eventually catch the attention of the FDA. On Friday April 13, 2018, the FDA announced steps to regulate “highly concentrated and pure” caffeine products.

“Today, the U.S. Food and Drug Administration took an important step to better protect consumers from the dangers of highly concentrated and pure caffeine products. These products present a significant public health threat because of the high risk that they will be erroneously used at excessive, potentially dangerous doses. Highly concentrated and pure caffeine, often sold in bulk packages, have been linked to at least two deaths in otherwise healthy individuals.” [link]

Pharmaceutical Landscape

The Pharmaceutical industry, one of the most tightly controlled industries in the world, manufactures products to a target value of plus or minus (±) a certain percent based on criteria for that product type. The nomenclature of a pure drug substance is also known as Active Pharmaceutical Ingredient (API); the Potency is referred to as an Assay value. Assay values that exceed 100% are not uncommon in the Pharmaceutical industry where formulators use pure API drug substances to which they add inactive ingredients, referred to as an excipient, to arrive at a target concentration of a formulated drug product. If a formulator uses an API with an Assay value of, say 101.2% for example, that formulator uses 101.2% in their calculation to formulate the product to a given target. This is such a normal and ubiquitous occurrence that the FDA expects to see Assay values for API’s and other chemical standards that exceed 100%.

United States Pharmocopeia (USP)

In the Pharmaceutical industry, many aspects of testing are outlined by the United States Pharmacopeia (USP), a non-profit entity that publishes standards for ingredient, products, and processes. They publish current versions of these standards annually.

The USP–NF is a combination of two compendia, the United States Pharmacopeia (USP) and the National Formulary (NF). It contains standards for medicines, dosage forms, drug substances, excipients, biologics, compounded preparations, medical devices, dietary supplements, and other therapeutics. The current version of USP–NF standards deemed official by USP are enforceable by the U.S. Food and Drug Administration for medicines manufactured and marketed in the United States. (http://www.uspnf.com/purchase-usp-nf)

The USP lists standards specific to purified substances (e.g. ascorbic acid, ibuprofen, pseudoephedrine, etc.) as well as the drug product formulated from these substances are in what are called monographs. While the USP is a non-governmental organization, the FDA considered these monographs (and other items contained in the current USP) as enforceable rule. The USP monographs describe the minimum tests substances or product must meet to be compliant in the United States. An example of a USP monograph for Ibuprofen is presented below.


One thing that should be immediately apparent is that the Assay specification for this substance, Ibuprofen, is between 97.0% and 103.0%.

Additional examples of other USP monographs with specifications above 100%:

  • Pseudoephedrine Hydrochloride contains not less than 98.0 percent and not more than 100.5 percent of C10H15NO·HCl, calculated on the dried basis.
  • Anhydrous Citric Acid contains not less than 99.5 percent and not more than 100.5 percent of C6H8O7, calculated on the anhydrous basis.
  • Clarithromycin contains not less than 96.0 percent and not more than 102.0 percent of C38H69NO13, calculated on the anhydrous basis.

Questions Answered

Question: How can my product contain more than 100% CBD and how can the Pharmaceutical products described above contain more than 100%?

Answer: The accumulation of uncertainty.

Theoretically, you can’t have more than 100% of anything. Scientifically, when you combine the uncertainty of the 1) Chemical Standards, 2) Laboratory Processes, 3) Laboratory Equipment, and 4) Laboratory Personnel, the additive effect of uncertainty translates into the final Assay value which can derive values in excess of 100% for ultra-pure compounds.

The goal of any laboratory is to minimize the uncertainty to the best of their scientific ability. At Botanacor Laboratories, we have built our laboratory on the same foundation and protocols required in any FDA-compliant Pharmaceutical quality control laboratory. We follow current Good Manufacturing Practices (cGMP) and Good Laboratory Practices (GLP), which allows us to provide the highest level of accuracy with the lowest level of uncertainty.

Question: Why don’t you just change the lab report to say 100%?

Answer: Let’s say we test a CBD isolate and the value for CBD is 102.1%. While a CBD value of 102.1% may seem like an anomaly to the end user, it’s legally defendable and scientifically accurate. Every data point and calculation to derive at 102.1% stands on sound scientific principles. To merely change a number at the request of a manufacturer or end user because they aren’t experienced in these scientific practices would completely negate the defensibility of the data. Furthermore, manufacturers formulating products on a -2.1% “fudge-factor” would be formulating inaccurately.

This may feel like a new concept for the burgeoning CBD industry; however, we can attest this is a very common occurrence in scientific analysis. Values exceeding 100% have been measured for decades and will be measured for decades to come. This isn’t exclusive to CBD, THC, or any other cannabis product. This is consistent with scientific measurement practices.

Alleviation of Confusion

Values greater than 100% in the scientific community are simply accepted. Chemists, formulators, management, FDA auditors and the like, all understand this concept and have all accepted it for decades. A new sector of talent is entering this scientific community, the Cannabinoid Purification Manufacturer, who in most cases have not been introduced to this concept.

Never before has a consumer product been manufactured, purified, and sold on the open market directly to consumers, so seeing a lab report with CBD results over 100% purity can be confusing to the layperson. If these products were being sold to scientific professionals, who intend to manufacture products from this as a starting material, they would simply use that Assay value in their formulations.

Updated on May 23, 2019

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