NIST to Help Labs Achieve Accurate THC, CBD Measurements
The difference between marijuana and hemp is a matter of measurement.
The National Institute of Standards and Technology (NIST) has launched a program to help laboratories accurately measure key chemical compounds in marijuana, hemp and other cannabis products including oils, edibles, tinctures and balms. The program aims to increase accuracy in product labeling and help forensic laboratories distinguish between hemp, which is legal in all states, and marijuana, which is not.
As part of the Cannabis Quality Assurance (CannaQAP) program, NIST will send hemp oil samples to participating labs, which will then measure the concentration of various compounds and report back to NIST. Future exercises will involve plant material.
The labels on most cannabis products list the concentration of at least two chemical compounds: tetrahydrocannabinol, or THC, the psychoactive ingredient that produces a high, and cannabidiol, or CBD, which is not intoxicating but is sought after for its many purported health benefits. However, most laboratories have limited experience making these measurements, which can sometimes be unreliable as a result.
The goal of the program, said NIST research chemist Brent Wilson, is to help labs produce consistent measurement results. “When you walk into a store or dispensary and see a label that says 10% CBD, you want to know that you can trust that number.”
Those numbers are also important as a matter of criminal law. The Agriculture Improvement Act of 2018, also called the 2018 Farm Bill, legalized any cannabis material with a THC concentration below 0.3%. Below that number, it’s hemp. At or above that number, it’s marijuana, and illegal in many states and by federal law. A farmer’s crop can be destroyed based on that number, and interstate shipments can be seized.
Before the 2018 law, most crime labs determined if something was marijuana by testing only for the presence of THC, not by measuring the concentration. The law now requires concentration measurements, and producing accurate numbers at levels as low as 0.3% can be a particular challenge.
“When you walk into a store or dispensary and see a label that says 10% CBD, you want to know that you can trust that number.” —NIST research chemist Brent Wilson
Here’s how CannaQAP will work. In the first round of exercises, NIST will send hemp oil samples — all with the same, very carefully measured concentrations of THC, CBD and 15 other cannabinoid compounds — to participating labs. Those labs won’t be told the concentrations of those compounds but will measure them and send their results back to NIST, along with information about the methods they used to do the analysis.
After collecting responses, NIST will publish the measurements the labs obtained. That data will be anonymized so that the names of the individual labs are not revealed. However, the results will show how much variability there is between labs. Also, NIST will publish the correct measurements, so each lab will be able to see how accurate its measurements were and how it performed relative to its peers.
“Anonymity means that labs don’t have to worry about how their performance will be viewed,” said NIST research chemist Melissa Phillips. “Our goal is to help labs improve, not to call them out.”
The NIST researchers will also assess whether some laboratory methods consistently produce better results than others. If so, they can recommend that labs adopt the better-performing methods.
Once that first round of exercises is complete and the data is published, which could take from six months to a year, NIST will run a second round of exercises. “We hope to see a tightening of the numbers the second time around,” Wilson said.
NIST is also planning to conduct future exercises with ground hemp and possibly marijuana. Those exercises will involve measuring a larger number of compounds, including terpenes — the chemicals that give different strains of marijuana their distinct aromas — and compounds that people don’t want in their cannabis such as fungal toxins, pesticides and heavy metals. Future exercises may also include extracts, concentrates, distillates and edibles.
NIST is also working on a hemp reference material — that is, a material that comes with known, accurate measurement values. Labs will be able to use that material to validate their measurement methods. One reason these measurements vary so much from lab to lab is that, currently, there are no reference materials for cannabis.
“Labs can accurately measure how much sugar is in your orange juice because they have standardized methods and reference materials for that type of product,” said Susan Audino, a chemistry consultant and science adviser to the Cannabis Analytical Science Program of the AOAC International, a group that establishes standard methods for laboratory analysis. “But cannabis has been a Schedule I drug since the ‘70s,” she said, referring to the Drug Enforcement Administration’s designation for drugs that have the highest potential for abuse.
NIST produces thousands of standard reference materials and has a long history of conducting quality assurance programs for improving measurements. Past programs have helped labs accurately measure compounds in dietary supplements, vitamins in human serum and environmental contaminants in groundwater.
“Our goal is to support U.S. industries by helping labs achieve high-quality measurements,” Phillips said.
Laboratories that are interested in participating in CannaQAP can find more information and can register online. Registration in the first exercise involving hemp oil will be open through Aug. 31, 2020.
What You Need to Know (And What We’re Working to Find Out) About Products Containing Cannabis or Cannabis-derived Compounds, Including CBD
The FDA is working to answer questions about the science, safety, and quality of products containing cannabis and cannabis-derived compounds, particularly CBD.
- Cannabis is a plant of the Cannabaceae family and contains more than eighty biologically active chemical compounds. The most commonly known compounds are delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). THC is the component that produces the “high” associated with marijuana use. Much interest has been seen around CBD and its potential related to health benefits.
- Marijuana is different from CBD. CBD is a single compound in the cannabis plant, and marijuana is a type of cannabis plant or plant material that contains many naturally occurring compounds, including CBD and THC.
- The FDA has approved only one CBD product, a prescription drug product to treat seizures associated with Lennox Gastaut syndrome (LGS), Dravet syndrome (DS), or tuberous sclerosis complex (TSC) in people one year of age and older.
- It is currently illegal to market CBD by adding it to a food or labeling it as a dietary supplement.
- The FDA has seen only limited data about CBD safety and these data point to real risks that need to be considered before taking CBD for any reason.
- Some CBD products are being marketed with unproven medical claims and are of unknown quality.
- The FDA will continue to update the public as it learns more about CBD.
Potential harm, side effects and unknowns
- CBD has the potential to harm you, and harm can happen even before you become aware of it.
- CBD can cause liver injury.
- CBD can affect how other drugs you are taking work, potentially causing serious side effects.
- Use of CBD with alcohol or other drugs that slow brain activity, such as those used to treat anxiety, panic, stress, or sleep disorders, increases the risk of sedation and drowsiness, which can lead to injuries.
- Male reproductive toxicity, or damage to fertility in males or male offspring of women who have been exposed, has been reported in studies of animals exposed to CBD.
- CBD can cause side effects that you might notice. These side effects should improve when CBD is stopped or when the amount used is reduced.
- Changes in alertness, most commonly experienced as somnolence (drowsiness or sleepiness).
- Gastrointestinal distress, most commonly experienced as diarrhea and/or decreased appetite.
- Changes in mood, most commonly experienced as irritability and agitation.
- There are many important aspects about CBD that we just don’t know, such as:
- What happens if you take CBD daily for sustained periods of time?
- What level of intake triggers the known risks associated with CBD?
- How do different methods of consumption affect intake (e.g., oral consumption, topical , smoking or vaping)?
- What is the effect of CBD on the developing brain (such as on children who take CBD)?
- What are the effects of CBD on the developing fetus or breastfed newborn?
- How does CBD interact with herbs and other plant materials?
- Does CBD cause male reproductive toxicity in humans, as has been reported in studies of animals?
Unanswered questions about the science, safety, and quality
You may have noticed that cannabidiol (CBD) seems to be available almost everywhere, and marketed as a variety of products including drugs, food, dietary supplements, cosmetics, and animal health products. Other than one prescription drug product to treat seizures associated with Lennox Gastaut syndrome (LGS), Dravet syndrome (DS), or tuberous sclerosis complex (TSC) in people one year of age and older, the U.S. Food and Drug Administration (FDA) has not approved any other CBD products, and there is very limited available information about CBD, including about its effects on the body.
The FDA recognizes the significant public interest in cannabis and cannabis-derived compounds, particularly CBD. However, there are many unanswered questions about the science, safety, and quality of products containing CBD. The agency is working on answering these questions through ongoing efforts including feedback from a recent FDA hearing and information and data gathering through a public docket.
Despite the 2018 Farm Bill removing hemp — defined as cannabis and cannabis derivatives with very low concentrations (no more than 0.3% on a dry weight basis) of THC — from the definition of marijuana in the Controlled Substances Act, CBD products are still subject to the same laws and requirements as FDA-regulated products that contain any other substance.
The FDA is concerned that people may mistakenly believe that using CBD “can’t hurt.” The agency wants to be clear that we have seen only limited data about CBD’s safety and these data point to real risks that need to be considered. As part of the drug review and approval process for the prescription drug containing CBD, it was determined that the risks are outweighed by the benefits of the approved drug for the particular population for which it was intended. Consumer use of any CBD products should always be discussed with a healthcare provider. Consumers should be aware of the potential risks associated with using CBD products. Some of these can occur without your awareness, such as:
- Liver Injury: During its review of the marketing application for Epidiolex — a purified form of CBD that the FDA approved in 2018 for use in the treatment of two rare and severe seizure disorders — the FDA identified certain safety risks, including the potential for liver injury. This serious risk can be managed when an FDA-approved CBD drug product is taken under medical supervision, but it is less clear how it might be managed when CBD is used far more widely, without medical supervision, and not in accordance with FDA-approved labeling. Although this risk was increased when taken with other drugs that impact the liver, signs of liver injury were seen also in patients not on those drugs. The occurrence of this liver injury was identified through blood tests, as is often the case with early problems with the liver. Liver injury was also seen in other studies of CBD in published literature. We are concerned about potential liver injury associated with CBD use that could go undetected if not monitored by a healthcare provider.
- Drug Interactions: Information from studies of the FDA-approved CBD drug Epidiolex show that there is a risk of CBD impacting other medicines you take – or that other medicines you take could impact the dose of CBD that can safely be used. Taking CBD with other medications may increase or decrease the effects of the other medications. This may lead to an increased chance of adverse effects from, or decreased effectiveness of, the other medications. Drug interactions were also seen in other studies of CBD in published literature. We are concerned about the potential safety of taking other medicines with CBD when not being monitored by a healthcare provider. In addition, there is limited research on the interactions between CBD products and herbs or other plant-based products in dietary supplements. Consumers should use caution when combining CBD products with herbs or dietary supplements.
- Male Reproductive Toxicity: Studies in laboratory animals showed male reproductive toxicity, including in the male offspring of CBD-treated pregnant females. The changes seen include decrease in testicular size, inhibition of sperm growth and development, and decreased circulating testosterone, among others. Because these findings were only seen in animals, it is not yet clear what these findings mean for human patients and the impact it could have on men (or the male children of pregnant women) who take CBD. For instance, these findings raise the concern that CBD could negatively affect a man’s fertility. Further testing and evaluation are needed to better understand this potential risk.
In addition, CBD can be the cause of side effects that you might notice. These side effects should improve when CBD is stopped or when the amount used is reduced. This could include changes in alertness, most commonly experienced as somnolence (sleepiness), but this could also include insomnia; gastrointestinal distress, most commonly experienced as diarrhea and/or decreased appetite but could also include abdominal pain or upset stomach; and changes in mood, most commonly experienced as irritability and agitation.
The FDA is actively working to learn more about the safety of CBD and CBD products, including the risks identified above and other topics, such as:
- Cumulative Exposure: The cumulative exposure to CBD if people access it across a broad range of consumer products. For example, what happens if you eat food with CBD in it, use CBD-infused skin cream and take other CBD-based products on the same day? How much CBD is absorbed from your skin cream? What if you use these products daily for a week or a month?
- Special Populations: The effects of CBD on other special populations (e.g., the elderly, children, adolescents, pregnant and lactating women).
- CBD and Animals: The safety of CBD use in pets and other animals, including considerations of species, breed, or class and the safety of the resulting human food products (e.g., meat milk, or eggs) from food-producing species.
Unproven medical claims, unsafe manufacturing practices
Some CBD Products are Being Marketed with Unproven Medical Claims and Could be Produced with Unsafe Manufacturing Practices
Unlike the FDA-approved CBD drug product, unapproved CBD products, which could include cosmetics, foods, products marketed as dietary supplements, and any other product (other than Epidiolex) making therapeutic claims, have not been subject to FDA evaluation regarding whether they are effective to treat a particular disease or have other effects that may be claimed. In addition, they have not been evaluated by the FDA to determine what the proper dosage is, how they could interact with other drugs or foods, or whether they have dangerous side effects or other safety concerns.
Misleading, unproven, or false claims associated with CBD products may lead consumers to put off getting important medical care, such as proper diagnosis, treatment, and supportive care. For that reason, it’s important to talk to your doctor about the best way to treat diseases or conditions with available FDA-approved treatment options.
In addition to safety risks and unproven claims, the quality of many CBD products may also be in question. The FDA is also concerned that a lack of appropriate processing controls and practices can put consumers at additional risks. For example, the agency has tested the chemical content of cannabinoid compounds in some of the products, and many were found to not contain the levels of CBD they claimed. We are also investigating reports of CBD potentially containing unsafe levels of contaminants (e.g., pesticides, heavy metals, THC).
CBD products are also being marketed for pets and other animals. The FDA has not approved CBD for any use in animals and the concerns regarding CBD products with unproven medical claims and of unknown quality equally apply to CBD products marketed for animals. The FDA recommends pet owners talk with their veterinarians about appropriate treatment options for their pets.
The FDA’s top priority is to protect the public health. This priority includes making sure consumers know about products that put their health and safety at greatest risk, such as those claiming to prevent, diagnose, treat, mitigate, or cure serious diseases. For example, the agency has warned companies to stop selling CBD products they claim are intended to prevent, diagnose, treat, mitigate, or cure serious diseases such as cancer, Alzheimer’s disease, psychiatric disorders and diabetes. While we have focused on these types of products, we will continue to monitor the marketplace for any product that poses a risk to public health, including those with dangerous contaminants, those marketed to vulnerable populations, and products that otherwise put the public health at risk.
Evaluation of the regulatory frameworks
The FDA is Continuing to Evaluate the Regulatory Frameworks for Products Containing Cannabis and Cannabis-Derived Compounds
The FDA continues to believe the drug approval process represents the best way to ensure that safe and effective new medicines, including any drugs derived from cannabis, are available to patients in need of appropriate medical therapy. The agency is committed to supporting the development of new drugs, including cannabis and cannabis-derived drugs, through the investigational new drug and drug approval process.
We are aware that there may be some products on the market that add CBD to a food or label CBD as a dietary supplement. Under federal law, it is illegal to market CBD this way.
The FDA is evaluating the regulatory frameworks that apply to certain cannabis-derived products that are intended for non-drug uses, including whether and/or how the FDA might consider updating its regulations, as well as whether potential legislation might be appropriate. The information we have underscores the need for further study and high quality, scientific information about the safety and potential uses of CBD.
The FDA is committed to setting sound, science-based policy. The FDA is raising these safety, marketing, and labeling concerns because we want you to know what we know. We encourage consumers to think carefully before exposing themselves, their family, or their pets, to any product, especially products like CBD, which may have potential risks, be of unknown quality, and have unproven benefits.
Our Consumer Update includes a practical summary of what we know to date. As we learn more, our goal is to update you with the information you need to make informed choices about CBD products. Also, as the regulatory pathways are clarified we will take care to inform all stakeholders as quickly as possible.
CBD products are everywhere. But do they work?
By now, you’ve probably run into a product containing cannabidiol, also known as CBD. It’s in everything from drinks and pet products to lotions and chewable gummies. Even major drugstore chains have announced they will start carrying CBD products in certain states.
But many people still don’t really know what CBD is. Is it marijuana? Is it legal? Does it actually work? Is it safe?
The answers to those questions aren’t necessarily straightforward. The only thing that is clear at this point: The marketing has gone way ahead of the science and the law when it comes to CBD products.
That said, CBD is thought to be a safe and effective option for certain conditions. Below, we sort through the confusion by answering some of the most common questions about CBD.
Is CBD marijuana?
Yes and no. Cannabidiol is one of the two best-known active compounds derived from the marijuana plant. The other is tetrahydrocannabinol, or THC, which is the substance that that produces the “high” from marijuana.
CBD does not get you high, but the idea that it’s not psychoactive is something of a misconception in his opinion. It does change your consciousness. You may feel mellow, experience less pain, and be more comfortable. In addition, some CBD products do contain small amounts of THC.
While CBD can come from marijuana, it can also be derived from hemp. Hemp is a related plant with 0.3% or less of THC. This plant is often used to make fabrics and ropes. As of 2018, Congress made hemp legal in all 50 states, and consequently CBD derived from hemp is also legal. The rules around marijuana-derived CBD, however, are far less clear.
Is marijuana-derived CBD legal?
Again, yes and no, depending on where you live. In some states marijuana is legal for both recreational use and medical use. In other states, it’s legal only for medical use. And in some areas, it’s not legal at all.
When it comes to CBD products, the FDA is still trying to get its arms around the issue. The agency is just starting the process of hashing out some rules regarding CBD sales. Officials recently formed a working group to create guidelines that could allow companies to legally market CBD products. Currently, CBD products are considered supplements, which aren’t FDA-regulated, and it is illegal for companies to make health or therapeutic claims about the products in their marketing. In announcing its effort to set CBD marketing rules, the FDA also signaled that it is cracking down on CBD companies that are using “egregious and unfounded claims” to market their products to “vulnerable populations.”
Currently, there is only one CBD product that has FDA approval: a prescription medication called Epidiolex, used to treat some rare severe seizure disorders in children. The bottom line is that in order to understand whether CBD is legal where you live, you’ll need to consult your state health department website or professionals in your community.
Does CBD work?
Yes, there is evidence that CBD works for some conditions, but certainly not all the conditions it is being promoted for these days. There’s no evidence, for example, that CBD cures cancer. There is moderate evidence that CBD can improve sleep disorders, fibromyalgia pain, muscle spasticity related to multiple sclerosis, and anxiety.
People report that oral CBD helps relieve anxiety and pain and also leads to better sleep. However, the same may not be true for a host of other CBD products on the market today, in particular those that are rubbed on the skin. It’s hard to know whether these have any clinical benefit, because they haven’t been tested sufficiently.
Testing also shows that many products don’t contain what’s claimed on the label. For example, they may have less CBD than advertised. So, buyer beware.
Where should you purchase CBD products?
If you are interested in trying a CBD product, it’s best to seek one through a dispensary, which is an establishment legally licensed to sell marijuana, if they are available in your state. Dispensary products must be labeled so you can see exactly how much CBD is in the product and whether it also contains THC. A small amount of THC in a CBD product isn’t typically problematic. But larger amounts could cause a “high” and may present a risk if you are going to drive.
Also, keep in mind that CBD products aren’t standardized and will vary. It helps to keep a journal recording what type of CBD product you took, how much, and your response to it. This will help you track what works and what doesn’t for your condition.
Is CBD safe?
The safest way to take CBD is orally, as a tablet, chewable, or tincture (a concentrated liquid typically administered with a dropper). Steer clear of any illegally sold synthetic CBD products, sometimes called “spice” or “bath salts.” These products have induced psychotic reactions in some people and pose a major health risk.
For adults, CBD appears to be a very safe product. CBD does produce side effects for some people, including nausea, fatigue, and irritability. It may also interact with certain medications, so always check with your doctor before use.
But for children under age 21 it’s a different story. It’s also not clear if any amount of CBD is appropriate for children.
Evidence regarding CBD is still building. Now that some states have legalized recreational and medical use of marijuana products, including CBD, scientists are finding it easier to conduct research. More will be known in the next 5 to 10 years, including whether there are yet undiscovered problems associated with long-term use.
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