Earlier this week Capitol Analysis Group, a cannabis-testing laboratory based in Lacey, Washington, announced they are conducting a “data-driven Lab Transparency Project, an effort to improve accuracy of cannabis testing results in the state through transparency and a new third-party auditing process,” according to a press release. They plan to look through the state’s traceability data to find patterns of deviations and possible foul play.
The project launch comes after Straightline Analytics, a Washington cannabis industry data company, released a report indicating they found rampant laboratory shopping to be present in the state. Lab shopping is a less-than-ethical business practice where cannabis producers look for the lab that will give them the most favorable results, particularly with respect to higher potency figures and lower contamination fail rates.“Lab shopping shouldn’t exist, because it is a symptom of lab variability,”
According to the press release, their report “shows that businesses that pay for the highest number of lab tests achieve, on average, reported potency levels 2.71% higher than do those that pay for the lowest number of lab tests.” They also found labs that provide higher potency figures tend to have the largest market share.
The Lab Transparency Project logo
The goal of The Lab Transparency Project is to provide summaries of lab data across the state, shining a light in particular on which labs provide the highest potency results. “Lab shopping shouldn’t exist, because it is a symptom of lab variability,” says Jeff Doughty, president of Capitol Analysis. “We already have standards that should prevent variations in lab results and proficiency testing that shows that the labs are capable of doing the testing.” The other piece to this project is independent third party auditing, where they hope other labs will collaborate in the name of transparency and honesty. “Problems arise when the auditors aren’t looking,” says Doughty. “Therefore, we’re creating the Lab Transparency Project to contribute to honesty and transparency in the testing industry.”
Dr. Jim McRae, founder of Straightline Analytics, and the author of that inflammatory report, has been a vocal critic of the Washington cannabis testing industry for years now. “I applaud Capitol Analysis for committing to this effort,” says McRae. “With the state’s new traceability system up and running following a 4-month breakdown, the time for openness and transparency is now.” Dr. McRae will be contributing to the summaries of lab data as part of the project.
According to Doughty, the project is designed to be a largely collaborative effort with other labs, dedicated to improving lab standards and transparency in the industry.
According to a press release sent out this morning, the American Association for Laboratory Accreditation (A2LA) accredited their first Pennsylvania cannabis-testing laboratory. Located in Harrisburg, PA, Keystone State Testing finalized their accreditation for ISO/IEC 17025 on February 21, 2018.
A2LA also accredited the laboratory to two cannabis-testing-specific programs, ISO/IEC 17025 – General Requirements for the Competence of Testing and Calibration Laboratories and A2LA R243 – Specific Requirements – Cannabis Testing Laboratory Accreditation Program. The R243 program is a collaboration with Americans for Safe Access (ASA) that takes some recommendation for regulators from the American Herbal Products Association (AHPA).
Dr. Kelly Greenland, owner and operator of Keystone State Testing
Keystone State Testing is now able to perform all of the tests for cannabis products under the state of Pennsylvania’s regulations. According to Dr. Kelly Greenland, owner and operator of Keystone State Testing, getting accredited is about safeguarding patient safety. “Keystone State Testing is proud to be the first Pennsylvania laboratory to earn A2LA ISO/IEC 17025 accreditation as well as ASA’s Patient Focused Certification,” says Dr. Greenland. “We regard these accreditations and certifications as the first steps in ensuring patient safety and will continue to do everything within our power to ensure medical marijuana patient safety.”
A2LA General Manager Adam Gouker says he wants to see more accreditations include the ASA requirements in R243. “A2LA is pleased to see the growing adoption of the combined assessment to include the ASA requirements,” says Gouker. “Our staff has worked tirelessly in conjunction with ASA staff to create this combined program and offer something that no other accreditation body in the world offers. We congratulate Keystone State Testing Labs on leading the charge in the state of Pennsylvania and laying the groundwork for future laboratories to follow.”
Government regulations keep millions of Americans safe every year by controlling what companies can put in their products and the standards those products must meet to be sold to consumers.
Enter the strange case of legal cannabis: In order for cannabis to be legally distributed by licensed medical professionals and businesses, it must be tested. But unlike other consumable goods, cannabis is not regulated by the FDA. Without an overarching federal policy requiring cannabis testing laboratory accreditation, the testing and laboratory requirements differ greatly across state lines.For medical cannabis specifically, accredited testing facilities are especially important.
To be federally regulated, cannabis would first have to be federally legalized. It turns out that states and businesses alike are not willing to wait for a federal mandate. Many states have begun to adopt standards for cannabis testing and some, such as Ohio, have even announced mandatory ISO/IEC 17025 accreditation for all cannabis testing laboratories. As the industry evolves, increased compliance expectations are certain to evolve in tandem.
Some cannabis labs have even taken the initiative to seek ISO/IEC 17025 accreditation of their own volition. Seth Wong, President of TEQ Analytics Laboratories, shared in a press release:
“By achieving ISO/IEC 17025 accreditation, TEQ Analytical Labs believes that we can address the concerns throughout the cannabis industry regarding insufficient and unreliable scientific analysis by providing our clients with State required tests that are accredited by an international standard.”
Other laboratories, such as DB Labs in Las Vegas and EVIO Labs in Florida are also leading the accreditation charge in their respective states, ahead of any state mandates.
There are key reasons why accreditation in cannabis testing labs is important. First and foremost, cannabis is a consumable product. Like fruits and vegetables, cannabis is prone to pesticides, fungi and contaminants. The result of putting a potentially hazardous material on the market without proper and documented testing could lead to a public health crisis. An accredited testing lab, however, will ensure that the cannabis products they test are free from harmful contaminants.
By utilizing role-based trainings, labs can trust employees are receiving proper onboarding.
For medical cannabis specifically, accredited testing facilities are especially important. Because many consumers of medical cannabis are immuno-compromised (such as in the case of chemotherapy patients), ensuring that products are free from any and all contaminants is critical. Further, in order to accurately determine both short- and long-term effects of prescribed cannabis consumption, accredited and compliant laboratories are necessary.
Accreditation standards like ISO/IEC 17025 also provide confidence that testing is performed properly and to an internationally accepted standard. Rather than returning a “pass/fail” rating on products, the Cannabis Safety Institute reports that an ISO/IEC 17025 laboratory is required to produce numerical accuracy percentages in testing for “at a minimum, cannabinoids, pesticides, microbiology, residual solvents, and water activity.” Reliable data sets that can be reviewed by both accreditors and the public foster trust between producers and consumers.
Finally, ISO/IEC 17025 accreditation demonstrates that a laboratory is properly staffed and trained. The Cannabis Safety Institute’s “Standards for Cannabis Testing Laboratories” explains that conducting proper analytical chemistry on cannabinoids (the chemical compounds extracted from cannabis that alter the brain’s neurotransmitter release) requires personnel who have met specific academic and training credentials. A system to monitor, manage and demonstrate proficiency is necessary to achieve and maintain accreditation. With electronic systems in place, this management and documentation minimizes risk and also minimizes administrative time tracking and maintaining training records.
Following the proper steps of a standardized process is key to improving and growing the cannabis industry in coming yearsFor cannabis testing labs, utilizing a comprehensive software solution to achieve and maintain compliance to standards such as ISO/IEC 17025 is key. Absent of a software solution, the necessary compliance requirements can become a significant burden to the organization. Paper tracking systems and complex spreadsheets open up organizations to the likelihood of errors and ultimately risk.
Because ISO/IEC 17025 has clearly defined expectations for training, a software solution also streamlines the training process while simultaneously documenting proficiency. By utilizing role-based trainings, organizations can be confident employees are receiving proper onboarding and in-service training. Additionally, the effectiveness of training can be proven with reports, which results in smoother audits and assessments.
Following the proper steps of a standardized process is key to improving and growing the cannabis industry in coming years- which means utilizing technology tools such as electronic workflows to ensure proper process controls. Beyond adding critical visibility, workflows also create efficiencies that can eliminate the need to increase staffing as companies expand and grow.
For an industry that is changing at a rapid pace, ensuring traceability, efficient processes and visibility across organizations is paramount. Using a system that enables automation, process control, document management and documented training procedures is a step in the right direction. With the proper software tools in place, cannabis testing labs can achieve compliance goals, demonstrate reliable and relevant results and most importantly ensure consumer safety.
By Dr. Zacariah Hildenbrand, Dr. Kevin A. Schug No Comments
Much has been made about the plummeting market value of cannabis grown outdoors in Oregon. This certainly isn’t a reflection of the product quality within the marketplace, but more closely attributable to the oversaturation of producers in this space. This phenomenon has similarities to that of ‘Tulip Mania’ within the Dutch Golden Age, whereby tulip bulbs were highly coveted assets one day, and almost worthless the next. During times like these, it is very easy for industry professionals to become disheartened; however, from a scientific perspective, this current era in Oregon represents a tremendous opportunity for discovery and fundamental research.
Dr. Zacariah Hildenbrand, chief technical officer at Inform Environmental.
As we have mentioned in previous presentations and commentaries, our research group is interested in exploring the breadth of chemical constituents expressed in cannabis to discover novel molecules, to ultimately develop targeted therapies for a wide range of illnesses. Intrinsically, this research has significant societal implications, in addition to the potential financial benefits that can result from scientific discovery and the development of intellectual property. While conducting our experiments out of Arlington, Texas, where the study of cannabis is highly restricted, we have resorted to the closet genetic relative of cannabis, hops (Humulus lupulus), as a surrogate model of many of our experiments (Leghissa et al., 2018a). In doing so, we have developed a number of unique methods for the characterization of various cannabinoids and their metabolites (Leghissa et al., 2018b; Leghissa et al., 2018c). These experiments have been interesting and insightful; however, they pale in comparison to the research that could be done if we had unimpeded access to diverse strains of cannabis, as are present in Oregon. For example, gas chromatography-vacuum ultraviolet spectroscopy (GC-VUV) is a relatively new tool that has recently been proven to be an analytical powerhouse for the differentiation of various classes of terpene molecules (Qiu et al., 2017). In Arlington, TX, we have three such GC-VUV instruments at our disposal, more than any other research institution in the world, but we do not have access to appropriate samples for application of this technology. Similarly, on-line supercritical fluid extraction – supercritical fluid chromatography – mass spectrometry (SFE-SFC-MS) is another capability currently almost unique to our research group. Such an instrument exhibits extreme sensitivity, supports in situ extraction and analysis, and has a wide application range for potential determination of terpenes, cannabinoids, pesticides and other chemical compounds of interest on a single analytical platform. Efforts are needed to explore the power and use of this technology, but they are impeded based on current regulations.
Dr. Kevin A. Schug, Professor and the Shimadzu Distinguished Professor of Analytical Chemistry in the Department of Chemistry and Biochemistry at The University of Texas at Arlington (UTA)
Circling back, let’s consider the opportunities that lie within the abundance of available outdoor-grown cannabis in Oregon. Cannabis is extremely responsive to environmental conditions (i.e., lighting, water quality, nutrients, exposure to pest, etc.) with respect to cannabinoid and terpene expression. As such, outdoor-grown cannabis, despite the reduced market value, is incredibly unique from indoor-grown cannabis in terms of the spectrum of light to which it is exposed. Indoor lighting technologies have come a long way; full-spectrum LED systems can closely emulate the spectral distribution of photon usage in plants, also known as the McCree curve. Nonetheless, this is emulation and nothing is ever quite like the real thing (i.e., the Sun). This is to say that indoor lighting can certainly produce highly potent cannabis, which exhibits an incredibly robust cannabinoid/terpene profile; however, one also has to imagine that such lighting technologies are still missing numerous spectral wavelengths that, in a nascent field of study, could be triggering the expression of unknown molecules with unknown physiological functions in the human body. Herein lies the opportunity. If we can tap into the inherently collaborative nature of the cannabis industry, we can start analyzing unique plants, having been grown in unique environments, using unique instruments in a facilitative setting, to ultimately discover the medicine of the future. Who is with us?
References
Leghissa A, Hildenbrand ZL, Foss FW, Schug KA. Determination of cannabinoids from a surrogate hops matrix using multiple reaction monitoring gas chromatography with triple quadrupole mass spectrometry. J Sep Sci 2018a; 41: 459-468.
Leghissa A, Hildenbrand ZL, Schug KA. Determination of the metabolites of Δ9-Tetrahydrocannabinol using multiple reaction monitoring gas chromatography – triple quadrapole – mass spectrometry. Separation Science Plus 2018b; 1: 43-47.
Leghissa A, Smuts J, Changling Q, Hildenbrand ZL, Schug KA. Detection of cannabinoids and cannabinoid metabolites using gas chromatography-vacuum ultraviolet spectroscopy. Separation Science Plus 2018c; 1: 37-42.
Qiu C, Smuts J, Schug KA. Analysis of terpenes and turpentines using gas chromatography with vacuum ultraviolet detection. J Sep Sci 2017; 40: 869-877.
Across the country, there is a patchwork of regulatory requirements that vary from state to state. Regulations focus on limiting microbial impurities (such as mold) present in cannabis in order for consumers to receive a safe product. When cultivators in Colorado and Nevada submit their cannabis product to laboratories for testing, they are striving to meet total yeast and mold count (TYMC) requirements.In a nascent industry, it is prudent for state regulators to reference specific testing methodologies so that an industry standard can be established.
TYMC refers to the number of colony forming units present per gram (CFU/g) of cannabis material tested. CFU is a method of quantifying and reporting the amount of live yeast or mold present in the cannabis material being tested. This number is determined by plating the sample, which involves spreading the sample evenly in a container like a petri dish, followed by an incubation period, which provides the ideal conditions for yeast and mold to grow and multiply. If the yeast and mold cells are efficiently distributed on a plate, it is assumed that each live cell will give rise to a single colony. Each colony produces a visible spot on the plate and this represents a single CFU. Counting the numbers of CFU gives an accurate estimate on the number of viable cells in the sample.
The plate count methodology for TYMC is standardized and widely accepted in a variety of industries including the food, cosmetic and pharmaceutical industries. The FDA has published guidelines that specify limits on total yeast and mold counts ranging from 10 to 100,000 CFU/g. In cannabis testing, a TYMC count of 10,000 is commonly used. TYMC is also approved by the AOAC for testing a variety of products, such as food and cosmetics, for yeast and mold. It is a fairly easy technique to perform requiring minimal training, and the overall cost tends to be relatively low. It can be utilized to differentiate between dead and live cells, since only viable living cells produce colonies.
Petri dish containing the fungus Aspergillus flavus. Photo courtesy of USDA ARS & Peggy Greb.
There is a 24 to 48-hour incubation period associated with TYMC and this impedes speed of testing. Depending on the microbial levels in a sample, additional dilution of a cannabis sample being tested may be required in order to count the cells accurately. TYMC is not species-specific, allowing this method to cover a broad range of yeast and molds, including those that are not considered harmful. Studies conducted on cannabis products have identified several harmful species of yeast and mold, including Cryptococcus, Mucor, Aspergillus, Penicillium and Botrytis Cinerea. Non-pathogenic molds have also been shown to be a source of allergic hypersensitivity reactions.The ability of TYMC to detect only viable living cells from such a broad range of yeast and mold species may be considered an advantage in the newly emerging cannabis industry.
After California voted to legalize recreational marijuana, state regulatory agencies began exploring different cannabis testing methods to implement in order to ensure clean cannabis for the large influx of consumers.
Unlike Colorado, California is considering a different route and the recently released emergency regulations require testing for specific species of Aspergillus mold (A. fumigatus, A. flavus, A. niger and A. terreus). While Aspergillus can also be cultured and plated, it is difficult to differentiate morphological characteristics of each species on a plate and the risk of misidentification is high. Therefore, positive identification would require the use of DNA-based methods such as polymerase chain reaction testing, also known as PCR. PCR is a molecular biology technique that can detect species-specific strains of mold that are considered harmful through the amplification and analysis of DNA sequences present in cannabis. The standard PCR testing method can be divided into four steps:
The double stranded DNA in the cannabis sample is denatured by heat. This refers to splitting the double strand into single strands.
Primers, which are short single-stranded DNA sequences, are added to align with the corresponding section of the DNA. These primers can be directly or indirectly labeled with fluorescence.
DNA polymerase is introduced to extend the sequence, which results in two copies of the original double stranded DNA. DNA polymerases are enzymes that create DNA molecules by assembling nucleotides, the building blocks of DNA.
Once the double stranded DNA is created, the intensity of the resulting fluorescence signal can uncover the presence of specific species of harmful Aspergillus mold, such as fumigatus.
These steps can be repeated several times to amplify a very small amount of DNA in a sample. The primers will only bind to the corresponding sequence of DNA that matches that primer and this allows PCR to be very specific.
PCR testing is used in a wide variety of applications Photo courtesy of USDA ARS & Peggy Greb.
PCR is a very sensitive and selective method with many applications. However, the instrumentation utilized can be very expensive, which would increase the overall cost of a compliance test. The high sensitivity of the method for the target DNA means that there are possibilities for a false positive. This has implications in the cannabis industry where samples that test positive for yeast and mold may need to go through a remediation process to kill the microbial impurities. These remediated samples may still fail a PCR-based microbial test due to the presence of the DNA. Another issue with the high selectivity of this method is that other species of potentially harmful yeast and mold would not even be detected. PCR is a technique that requires skill and training to perform and this, in turn, adds to the high overall cost of the test.
Both TYMC and PCR have associated advantages and disadvantages and it is important to take into account the cost, speed, selectivity, and sensitivity of each method. The differences between the two methodologies would lead to a large disparity in testing standards amongst labs in different states. In a nascent industry, it is prudent for state regulators to reference specific testing methodologies so that an industry standard can be established.
Last week, the 4th annual Emerald Conference brought attendees from around the world to San Diego for two days of education, networking and collaboration. Leading experts from across the industry shared some of the latest research in sessions and posters with over 600 attendees. The foremost companies in cannabis testing, research and extraction brought their teams to exhibit and share cutting edge technology solutions.
Ken Snoke, president of Emerald Scientific, delivers the opening remarks
The diversity in research topics was immense. Speakers touched on all of the latest research trends, including tissue culture as a micropropagation technique, phenotype hunting, pharmaceutical product formulation, chromatography methods and manufacturing standards, to name a few.
On the first day of the event, Ken Snoke, president of Emerald Scientific, gave his opening remarks, highlighting the importance of data-driven decisions in our industry, and how those decisions provide the framework and foundation for sound progress. “But data also fuels discovery,” says Snoke, discussing his remarks from the event. “I told a story of my own experience in San Diego almost 30 years ago while working in biotech, and how data analysis in a relatively mundane and routine screening program led to discovery. And how we (the folks at Emerald) believe that when we get our attendees together, that the networking and science/data that comes from this conference will not only support data-driven decisions for the foundation of the industry, but it will also lead to discovery. And that’s why we do this,” Snoke added.
Arun Apte, CEO of CloudLIMS, discusses his poster with an attendee
Snoke says the quality of the content at the poster session was phenomenal and engaging. “We had over 500 attendees so we continue to grow, but it’s not just about growth for us,” says Snoke. “It’s about the quality of the content, and providing a forum for networking around that content. I met a scientist that said this conference renewed his faith in our industry. So I firmly believe that the event has and will continue to have a profound and immensely positive impact on our industry.”
Introducing speakers as one of the chairs for first session focused on production, Dr. Markus Roggen says he found a number of speakers delivered fascinating talks. “This year’s lineup of presentations and posters really showcase how far the cannabis industry has come along,” says Dr. Roggen. “The presentations by Roger Little, PhD and Monica Vialpando, PhD, both showed how basic research and the transfer of knowledge from other industries can push cannabis science forward. Dr. Brian Rohrback’s presentation on the use of chemometrics in the production of pharmaceutical cannabis formulations was particular inspiring.”
Roger Little, Ph.D., owner of CTA, LLC, presents his research
Shortly after Snoke gave his opening remarks, Dr. Roggen introduced the first speaker, Roger Little, Ph.D., owner of CTA, LLC. He presented his research findings on phenotype hunting and breeding with the help of a cannabis-testing laboratory. He discussed his experience working with local breeders and growers in Northern California to identify high-potency plants early in their growth. “You can effectively screen juvenile plants to predict THC potency at harvest,” says Dr. Little. The other research he discussed included some interesting findings on the role of Methyl jasmonate as an immune-response trigger. “I was looking at terpenes in other plants and there is this chemical called methyl jasmonate,” says Dr. Little. “It is produced in large numbers of other plants and is an immune response stimulator. This is produced from anything trying to harm the plant such as a yeast infection or mites biting the stem.” Dr. Little says that the terpene has been used on strawberries to increase vitamin C content and on tobacco plants to increase nicotine content, among other uses. “It is a very potent and ubiquitous molecule,” says Dr. Little. “Cannabis plants’ immune-response is protecting the seeds with cannabinoid production. We can trick plants to think they are infected and thus produce more cannabinoids, stimulating them to produce their own jasmonate.”
Dr. Hope Jones, chief scientific officer of C4 Laboratories, spoke about tissue culture as an effective micropropagation technique, providing attendees with a basic understanding of the science behind it, and giving some estimates for how it could effectively replace cloning and the use of mother plants. You could overhear attendees discussing her talk throughout the remainder of the show.
Dr. Hope Jones, chief scientific officer at C4 Laboratories, discusses tissue culture during her talk
Dr. Jones has worked with CIJ on a series of articles to help explain cannabis tissue culture, which you can find here. “In this example, we started with one vessel with 4 explants,” says Dr. Jones. “Which when subcultured 4-6 weeks later, we now have 4 vessels with 16 plants.” She says this is instrumental in understanding how tissue culture micropropagation can help growers scale without the need for a ton of space and maintenance. From a single explant, you can potentially generate 70,000 plants after 48 weeks, according to Dr. Jones.
Those topics were just the first two of many presentations at Emerald Conference. You can take a look at some of the other presentation abstracts in the agenda here. The 5th Annual Emerald Conference in 2019 will be held February 28th through March 1st in San Diego next year.
As both recreational and medical cannabis legalization continues to progress across the country, each state is tasked with developing regulatory requirements to ensure that customers and patients receive clean cannabis for consumption. This requires cannabis to undergo laboratory testing that analyzes the presence of microbial impurities including yeast and mold.
Some states, such as Colorado, Nevada, Maine, Illinois and Massachusetts use total yeast and mold count testing (TYMC) and set a maximum yeast and mold count threshold that cultivators must fall below. Other states, such as California, require the detection of species-specific strains of Aspergillus mold (A. fumigatus, A. flavus, A. niger and A. terreus), which requires analyzing the DNA of a cannabis sample through polymerase chain reaction testing, also known as PCR.
Differences in state regulations can lead to different microbiological techniques implemented for testing.Before diving in further, it is important to understand the scientific approach. Laboratory testing requirements for cannabis can be separated into two categories: analytical chemistry methods and microbiological methods.
Analytical chemistry is the science of qualitatively and quantitatively determining the chemical components of a substance, and usually consists of some kind of separation followed by detection. Analytical methods are used to uncover the potency of cannabis, analyze the terpene profile and to detect the presence of pesticides, chemical residues, residuals solvents, heavy metals and mycotoxins. Analytical testing methods are performed first before proceeding to microbiological methods.
Petri dish containing the fungus Aspergillus flavus. It produces carcinogenic aflatoxins, which can contaminate certain foods and cause aspergillosis, an invasive fungal disease. Photo courtesy of USDA ARS & Peggy Greb.
Microbiological methods dive deeper into cannabis at a cellular level to uncover microbial impurities such as yeast, mold and bacteria. The techniques utilized in microbiological methods are very different from traditional analytical chemistry methods in both the way they are performed and target of the analysis. Differences in state regulations can lead to different microbiological techniques implemented for testing. There are a variety of cell and molecular biology techniques that can be used for detecting microbial impurities, but most can be separated into two categories:
Methods to determine total microbial cell numbers, which typically utilizes cell culture, which involves growing cells in favorable conditions and plating, spreading the sample evenly in a container like a petri dish. The total yeast and mold count (TYMC) test follows this method.
Molecular methods intended to detect specific species of mold, such as harmful aspergillus mold strains, which typically involves testing for the presence of unique DNA sequences such as Polymerase Chain Reaction (PCR).
Among states that have legalized some form of cannabis use and put forth regulations, there appears to be a broad consensus that the laboratories should test for potency (cannabinoids concentration), pesticides (or chemical residues) and residual solvents at a minimum. On the other hand, microbial testing requirements, particularly for mold, appear to vary greatly from state to state. Oregon requires random testing for mold and mildew without any details on test type. In Colorado, Nevada, Maine, Illinois and Massachusetts, regulations explicitly state the use of TYMC for the detection of mold. In California, the recently released emergency regulations require testing for specific species of Aspergillus mold (A. fumigatus, A. flavus, A. niger and A. terreus), which are difficult to differentiate on a plate and would require a DNA-based approach. Since there are differences in costs associated and data produced by these methods, this issue will impact product costs for cultivators, which will affect cannabis prices for consumers.
Cannabis strains used (clockwise from top left): Agent Orange, Tahoe OG, Blue Skunk, Grand Daddy and Grape Drink
Cannabis-testing laboratories have the challenge of removing a variety of unwanted matrix components from plant material prior to running extracts on their LC-MS/MS or GC-MS. The complexity of the cannabis plant presents additional analytical challenges that do not need to be accounted for in other agricultural products. Up to a third of the overall mass of cannabis seed, half of usable flower and nearly all extracts can be contributed to essential oils such as terpenes, flavonoids and actual cannabinoid content1. The biodiversity of this plant is exhibited in the over 2,000 unique strains that have been identified, each with their own pigmentation, cannabinoid profile and overall suggested medicinal use2. While novel methods have been developed for the removal of chlorophyll, few, if any, sample preparation methods have been devoted to removal of other colored pigments from cannabis.
Cannabis samples following QuEChERS extraction
Sample Preparation
Cannabis samples from four strains of plant (Purple Drink, Tahoe OG, Grand Daddy and Agent Orange) were hydrated using deionized water. Following the addition of 10 mL acetonitrile, samples were homogenized using a SPEX Geno/Grinder and stainless steel grinding balls. QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) non-buffered extraction salts were then added and samples were shaken. Following centrifugation, an aliquot of the supernatant was transferred to various blends of dispersive SPE (dSPE) salts packed into centrifugation tubes. All dSPE tubes were vortexed prior to being centrifuged. Resulting supernatant was transferred to clear auto sampler vials for visual analysis. Recoveries of 48 pesticides and four mycotoxins were determined for the two dSPE blends that provided the most pigmentation removal.
Seven dSPE blends were evaluated for their ability to remove both chlorophyll and purple pigmentation from cannabis plant material:
Based on the coloration of the resulting extracts, blends A, F and G were determined to be the most effective in removing both chlorophyll (all cannabis strains) and purple pigments (Purple Drink and Grand Daddy). Previous research regarding the ability of large quantities of GCB to retain planar pesticides allowed for the exclusion of blend G from further analyte quantitation3. The recoveries of the 48 selected pesticides and four mycotoxins for blends A and F were determined.
Grand Daddy following various dSPE cleanups
Summary
A blend of MgSO4, C18, PSA and Chlorofiltr® allowed for the most sample clean up, without loss of pesticides and mycotoxins, for all cannabis samples tested. Average recovery of the 47 pesticides and five mycotoxins using the selected dSPE blend was 75.6% were as the average recovery when including GCB instead of Chlorofiltr® was 67.6%. Regardless of the sample’s original pigmentation, this blend successfully removed both chlorophyll and purple hues from all strains tested. The other six dSPE blends evaluated were unable to provide the sample clean up needed or had previously demonstrated to be detrimental to the recovery of pesticides routinely analyzed in cannabis.
References
(1) Recommended methods for the identification and analysis of cannabis and cannabis products, United Nations Office of Drugs and Crime (2009)
(2) W. Ross, Newsweek, (2016)
(3) Koesukwiwat, Urairat, et al. “High Throughput Analysis of 150 Pesticides in Fruits and Vegetables Using QuEChERS and Low-Pressure Gas Chromatography Time-of-Flight Mass Spectrometry.” Journal of Chromatography A, vol. 1217, no. 43, 2010, pp. 6692–6703., doi:10.1016/j.chroma.2010.05.012.
The cannabis industry is probably more informed about patients and consumers of their products than the general food industry. In addition to routine illness and stress in the population, cannabis consumers are fighting cancer, HIV/AIDS and other immune disorders. Consumers who are already ill are immunocompromised. Transplant recipients purposely have their immune system suppressed in the process of a successful transplant. These consumers have pre-existing conditions where the immune system is weakened. If the immunocompromised consumer is exposed to viral or bacterial pathogens through cannabis products, the consumer is more likely to suffer from a viral infection or foodborne illness as a secondary illness to the primary illness. In the case of consumers with weakened immune systems, it could literally kill them.Bacteria, yeast, and mold are present in all environments.
The cannabis industry shoulders great responsibility in both the medical and adult use markets. In addition to avoiding chemical hazards and determining the potency of the product, the cannabis industry must manufacture products safe for consumption. There are three ways to control pathogens and ensure a safe product: prevent them from entering, kill them and control their growth.
Prevent microorganisms from getting in
Think about everything that is outdoors that will physically come in a door to your facility. Control the quality of ingredients, packaging, equipment lubricants, cleaning agents and sanitizers. Monitor employee hygiene. Next, you control everything within your walls: employees, materials, supplies, equipment and the environment. You control receiving, employee entrance, storage, manufacturing, packaging and distribution. At every step in the process, your job is to prevent the transfer of pathogens into the product from these sources.
Kill microorganisms
Colorized low-temperature electron micrograph of a cluster of E. coli bacteria. Image courtesy of USDA ARS & Eric Erbe
The combination of raw materials to manufacture your product is likely to include naturally occurring pathogens. Traditional heat methods like roasting and baking will kill most pathogens. Remember, sterility is not the goal. The concern is that a manufacturer uses heat to achieve organoleptic qualities like color and texture, but the combination of time and temperature may not achieve safety. It is only with a validated process that safety is confirmed. If we model safety after what is required of food manufacturers by the Food and Drug Administration, validation of processes that control pathogens is required. In addition to traditional heat methods, non-thermal methods for control of pathogens includes irradiation and high pressure processing and are appropriate for highly priced goods, e.g. juice. Killing is achieved in the manufacturing environment and on processing equipment surfaces after cleaning and by sanitizing.
If you have done everything reasonable to stop microorganisms from getting in the product and you have a validated step to kill pathogens, you may still have spoilage microorganisms in the product. It is important that all pathogens have been eliminated. Examples of pathogens include Salmonella, pathogenic Escherichia coli, also called Shiga toxin-producing E. coli (STEC) and Listeria monocytogenes. These three common pathogens are easily destroyed by proper heat methods. Despite steps taken to kill pathogens, it is theoretically possible a pathogen is reintroduced after the kill step and before packaging is sealed at very low numbers in the product. Doctors do not know how many cells are required for a consumer to get ill, and the immunocompromised consumer is more susceptible to illness. Lab methods for the three pathogens mentioned are designed to detect very low cell numbers. Packaging and control of growth factors will stop pathogens from growing in the product, if present.
Control the growth of microorganisms
These growth factors will control the growth of pathogens, and you can use the factors to control spoilage microbes as well. To grow, microbes need the same things we do: a comfortable temperature, water, nutrients (food), oxygen, and a comfortable level of acid. In the lab, we want to find the pathogen, so we optimize these factors for growth. When you control growth in your product, one hurdle may be enough to stop growth; sometimes multiple hurdles are needed in combination. Bacteria, yeast, and mold are present in all environments. They are at the bottom of the ocean under pressure. They are in hot springs at the temperature of boiling water. The diversity is immense. Luckily, we can focus on the growth factors for human pathogens, like Salmonella, pathogenic E. coli, and Listeria monocytogenes.
The petri dishes show sterilization effects of negative air ionization on a chamber aerosolized with Salmonella enteritidis. The left sample is untreated; the right, treated. Photo courtesy of USDA ARS & Ken Hammond
Temperature. Human pathogens prefer to grow at the temperature of the human body. In manufacture, keep the time a product is in the range of 40oF to 140oF as short as possible. You control pathogens when your product is at very hot or very cold temperatures. Once the product cools after a kill step in manufacturing, it is critical to not reintroduce a pathogen from the environment or personnel. Clean equipment and packaging play key roles in preventing re-contamination of the product.
Water. At high temperatures as in baking or roasting, there is killing, but there is also the removal of water. In the drying process that is not at high temperature, water is removed to stop the growth of mold. This one hurdle is all that is needed. Even before mold is controlled, bacterial and yeast growth will stop. Many cannabis candies are safe, because water is not available for pathogen growth. Packaging is key to keep moisture out of the product.
Nutrients. In general, nutrients are going to be available for pathogen growth and cannot be controlled. In most products nutrients cannot be removed, however, recipes can be adjusted. Recipes for processed food add preservatives to control growth. In cannabis as in many plants, there may be natural compounds which act as preservatives.
Oxygen. With the great diversity of bacteria, there are bacteria that require the same oxygen we breathe, and mold only grows in oxygen. There are bacteria that only grow in the absence of oxygen, e.g. the bacteria responsible for botulism. And then there are the bacteria and yeast in between, growing with or without oxygen. Unfortunately, most human pathogens will grow with or without oxygen, but slowly without oxygen. The latter describes the growth of Salmonella, E. coli, and Listeria. While a package seals out air, the growth is very slow. Once a package is opened and the product is exposed to air, growth accelerates.
Acid. Fermented or acidified products have a higher level of acid than non-acid products; the acid acts as a natural preservative. The more acid, the more growth is inhibited. Generally, acid is a hurdle to growth, however and because of diversity, some bacteria prefer acid, like probiotics which are non-pathogenic. Some pathogens, like E. coli, have been found to grow in low acid foods, e.g. juice, even though the preference is for non-acidic environments.
Proficiency Testing in the Cannabis Industry: An Inside Look
By Amanda Rigdon, Chief Technical Officer, Emerald Scientific
This presentation covers specifics of different proficiency testing schemes available to the cannabis industry. Additionally, specific challenges facing both laboratories and PT providers in the cannabis industry will be addressed. Data relating to residual solvent and potency proficiency testing will be presented.
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