Why Is THC Potency Testing So Important?
How much Tetrahydrocannabinol (THC) a cannabis product contains is chief among the questions a consumer has when buying their flower, concentrate, or edible. In many states, including New Jersey, this percentage is prominently affixed on every cannabis product label, and for good reason: This phytocannabinoid is the primary cause of intoxicating effects from cannabis. Many states with legal cannabis programs require cultivators and manufacturers to conduct testing for THC (among other phytocannabinoids like CBD) before their products are made available to the public.
Whether consumers want a high-THC product that offers a “heady” experience or “high,” or a low-THC product that will provide relief without the psychoactive effects, it is important for them to know the THC content of their cannabis. That is where THC potency testing comes in.
In this blog, you will learn:
How THC potency testing is conducted by a third-party laboratory
Why THC potency testing is important
What affects THC potency
What is THC potency testing?
THC potency testing determines the levels of THC present in cannabis flower, concentrates, and other products. This number is typically expressed either as a percentage, in milligrams, or both, depending on the product. For example, cannabis flower is often expressed as a percentage, while edibles are expressed as a total amount of THC per package, as well as an individual amount per serving.
How accurate is THC potency testing?
Cannabis plants possess a range of THC potency in various parts of the plant, and even within the same part of the plant. The cannabis flower itself may be a few percentage points higher or lower in THC in one part than another. This means flower from the same plant could be tested by two different labs and THC potency results may differ. To combat this, labs should use representative samples of flower from the plants throughout their testing process.
Since medical and adult-use high-THC cannabis is still federally illegal, there has been no oversight into the industry from the U.S. Food and Drug Administration (FDA), the U.S. Environmental Protection Agency (EPA), the United States Department of Agriculture (USDA), or other federal agencies. Due to the lack of federal oversight into marijuana and its testing, as well as the state-specific nuances and regulations, cannabis testing labs have been operating in an industry with a lack of standardized testing methodologies. Many different labs across the U.S. have their own variations of testing processes, which can make it difficult to compare results from lab to lab on an apples-to-apples basis. It is possible that similar cannabis products tested by two different labs may show different THC potency levels on their respective COAs.
While it is possible for these two factors to pose a challenge, there are several national and international standards organizations that have published literature proposing testing requirements of cannabis. These organizations include the Association of Official Analytical Chemists (AOAC International), the American Society for Testing Materials (ASTM), the United States Pharmacopoeia (USP), and the American Herbal Pharmacopoeia (AHP). Labs following best practices and incorporating standards from these organizations will help to ensure the accuracy of any cannabis testing results, including THC potency testing.
How THC potency testing is conducted
High-performance liquid chromatography (HPLC) is the predominant way THC potency testing is conducted. HPLC involves the use of a UV light detector called a Diode Array Detector (DAD) or Photodiode Array Detector (PAD) to gauge the levels of phytocannabinoids present. This method is most commonly used for testing edibles and concentrates and can identify THC, as well as variations of that phytocannabinoid, like THCA.
Gas chromatography used to be a prominent method for testing cannabis for THC potency, but it is now considered an outdated method. It is not utilized to the extent HPLC is utilized.
Why is THC potency testing important?
Cannabis brands contend with a competitive marketplace and need to establish trust with their customers. Understanding the THC content of a cannabis product is important for consumers to select a product suitable for them, to determine dosages, and to help them best plan for the experience they want to have.
THC potency testing, along with phytocannabinoid profiling, gives consumers deep insight into what’s present in their products and helps them make the best, most informed decisions for their needs. By knowing precisely how much THC they’re consuming -- and how much of that phytocannabinoid is present in relation to others found in the cannabis product of their choice -- they can best select the right item to support and repeat a mellow, energizing, pain-relieving, or relaxing experience.
After testing, a Certificate of Analysis (COA) will show the THC potency, along with the rest of the cannabinoid and terpene profiles and contaminants tested for as well. These tests can go a long way in establishing a rapport with customers, who will know that the company has nothing to hide about the quality of their products.
THC potency testing also helps to distinguish between low-THC industrial hemp and high-THC “marijuana,” a legal distinction based on the amount of the phytocannabinoid present in the product. Cannabis containing less than 0.3% THC content is considered industrial hemp and is legal for interstate commerce, while cannabis containing more THC remains federally illegal and can only be cultivated, processed, sold, and distributed within a state-level licensed system. THC potency testing is crucial to the nationwide hemp industry, as well as state-legal cannabis businesses.
The main takeaway: In addition to being a state requirement, THC potency testing gives consumers the information they need to make educated decisions at the dispensary. When used to test industrial hemp, THC potency testing ensures that the hemp meets the legal threshold of 0.3% or less total THC content.
What affects THC potency?
THC can degrade over time naturally, but it degrades faster when it comes into contact with certain environmental factors. These include light, oxygen, and moisture. Here’s how each affects the overall THC potency of a cannabis product.
Time: THC begins to degrade the moment cannabis is harvested. A byproduct of the THC degradation process is the production of another cannabinoid known as Cannabinol (CBN) and the reduction of overall THC potency.
Light: Ultraviolet (UV) light causes organic matter to slowly break down, and THC is no exception. To preserve potency, cannabis should be kept in a dark place, both during transport and in final consumer packaging.
Moisture: In addition to the risk of molds and mildews destroying an entire harvest, reintroducing moisture back into cannabis flower can cause THC degradation.
Oxygen: Cannabinol (CBN) is a byproduct of THC degradation due to oxidation. This is because the natural rate of THC degradation is markedly increased in highly oxygenated environments.
Is THC potency testing required in New Jersey?
Most states require THC potency testing for both medical and adult-use cannabis products. New Jersey requires potency testing for all medical marijuana and industrial hemp, and will soon require the same for adult-use cannabis. The state’s interim testing rules, which are the defined testing standards implemented by Maryland’s Medical Cannabis Commission, require independent testing of cannabis products to include a profile of major cannabinoids, including THC potency. New Jersey authorities also require testing for pesticides, microbes, heavy metals, and residual solvents, among others.
THC potency testing can set cannabis brands apart
In New Jersey, the legal cannabis industry is young and growing. As it expands on the medical side and adult-use sales begin, cannabis brands are going to face fierce competition in differentiating themselves from other license holders.
True Labs for Cannabis offers precise, meticulous cannabis testing at the highest possible standards, not only for THC potency but the full spectrum of phytocannabinoids and terpenes. Additionally, True Labs for Cannabis offers testing for pesticides, microbes, heavy metals, mycotoxins, and residual solvents. Consumers expect full transparency, especially from legal cannabis brands that are paving the way in the post-prohibition era. Rigorous cannabis testing and establishing consumer trust while ensuring all regulatory guidelines are met, is a winning combination for cannabis businesses in the Garden State.