Cannabis testing to detect microbial contamination is complicated. It may not be rocket science, but it is life science, which means it’s a moving target, or at least, it should be, as we acquire more and more information about how the world we live in works. We are lucky to be able to carry out that examination in ever increasing detail. For instance, the science of genomics1 was born over 80 years ago, and just twenty years ago, genetics was still a black box. We’ve made tremendous progress since those early days, but we still have a long way to go, to be sure.
Much of that progress is due to our ability to build more accurate tools, a technological ladder, if you will, that raises our awareness, expertise, and knowledge to new levels. When a new process or technology appears, we compare it against accepted practice to create a new paradigm and make the necessary adjustments. But people have to be willing to change. In the cannabis industry, rapid change is a constant, first because that is the nature of a nascent industry, and second because in the absence of some universal and unimpeachable standard, it’s difficult to know who’s right. Especially when the old, reliable reference method (i.e. plating, which is basically growing microorganisms on the surface of a nutritional medium) is deeply flawed in its application to cannabis testing vs. molecular methods (i.e., quantitative polymerase chain reaction, or qPCR for short).
Dr. Sherman Hom, Director of Regulatory Affairs at Medicinal Genomics
Plating systems have been used faithfully for close to 130 years in the food industry, and has performed reasonably well.2 But cannabis isn’t food and can’t be tested as if it were. In fact, plating methods have a host of major disadvantages that only show up when they’re used to detect cannabis pathogens. They are, in no particular order:
A single plating system can’t enumerate a group of microorganisms and/or detect specific bacterial and fungal pathogens. This is further complicated by the fact that better than 98% of the microbes in the world do not form colonies.3 And there is no ONE UNIVERSAL bacterial or fungal SELECTIVE agar plate that will allow the growth of all bacteria or all fungal strains. For example, the 5 genus species of fungal strains implicated in powderly mildew DO NOT plate at all.
Cannabinoids, which can represent 10-30% of a cannabis flower’s weight, have been shown to have antibacterial activity.4 Antibiotics inhibit the growth of bacteria and in some cases kill it altogether. Salmonella species & shiga toxin producing coli (STEC) bacteria, in particular, are very sensitive to antibiotics, which leads to either a false negative result or lower total counts on plates vs. qPCR methods.
Plating methods cannot detect bacterial and fungal endophytes that live a part or all of their life cycle inside a cannabis plant.5,6 Examples of endophytes are the Aspergillus pathogens (A. flavus, A. fumigatus, A. niger, and A. terreus). Methods to break open the plant cells to access these endophytes to prepare them for plating methods also lyse these microbial cells, thereby killing endophytic cells in the process. That’s why these endophytes will never form colonies, which leads to either false negative results or lower total counts on plates vs. qPCR methods.
Selective plating media for molds, such as Dichloran Rose-Bengal Chloramphenicol (DRBC) actually reduces mold growth—especially Aspergillus—by as much as 5-fold.This delivers false negative results for this dangerous human pathogen. In other words, although the DRBC medium is typically used to reduce bacteria; it comes at the cost of missing 5-fold more yeast and molds than Potato Dextrose Agar (PDA) + Chloramphenicol or molecular methods. These observations were derived from study results of the AOAC emergency response validation.7
Finally, we’ve recently identified four bacterial species, which are human pathogens associated with cannabis that do not grow at the plating system incubation temperature typically used.8 They are Aeromonas hydrophila, Pantoea agglomerans, Yersinia enterocolitica, and Rahnella aquatilis. This lowers total counts on plates qPCR methods.
So why is plating still so popular? Better yet, why is it still the recommended method for many state regulators? Beats me. But I can hazard a couple of guesses.
A yeast and mold plate test
First, research on cannabis has been restricted for the better part of the last 70 years, and it’s impossible to construct a body of scientific knowledge by keeping everyone in the dark. Ten years ago, as one of the first government-employed scientists to study cannabis, I was tapped to start the first cannabis testing lab at the New Jersey Dept. of Health and we had to build it from ground zero. Nobody knew anything about cannabis then.
Second, because of a shortage of cannabis-trained experts, members of many regulatory bodies come from the food industry—where they’ve used plating almost exclusively. So, when it comes time to draft cannabis microbial testing regulations, plating is the default method. After all, it worked for them before and they’re comfortable with recommending it for their state’s cannabis regulations.
Finally, there’s a certain amount of discomfort in not being right. Going into this completely new area—remember, the legal cannabis industry didn’t even exist 10 years ago—we human beings like to have a little certainty to fall back on. The trouble is, falling back on what we did before stifles badly needed progress. This is a case where, if you’re comfortable with your old methods and you’re sure of your results, you’re probably wrong.
So let’s accept the fact that we’re all in this uncharted territory together. We don’t yet know everything about cannabis we need to know, but we do know some things, and we already have some pretty good tools, based on real science, that happen to work really well. Let’s use them to help light our way.
References
J. Weissenbach. The rise of genomics. Comptes Rendu Biologies, 339 (7-8), 231-239 (2016).
R. Koch. 1882. Die Aetiologie der Tuberculose. Berliner Klinische Wochenschrift, 19, 221-230 (1882).
W. Wade. Unculturable bacteria—the uncharacterized organisms that cause oral infections. Journal of the Royal Society of Medicine, 95(2), 91-93 (2002).
J.A. Karas, L.J.M. Wong, O.K.A. Paulin, A. C. Mazeh, M.H. Hussein, J. Li, and T. Vekov. Antibiotics, 9(7), 406 (2020).
M. Taghinasab and S. Jabaji, Cannabis microbiome and the role of endophytes in modulating the production of secondary metabolites: an overview. Microorganisms 2020, 8, 355, 1-16 (2020).
P. Kusari, S. Kusari, M. Spiteller and O. Kayser, Endophytic fungi harbored in Cannabis sativa L.: diversity and potential as biocontrol agents against host plant-specific phytopathogens. Fungal Diversity 60, 137–151 (2013).
K. McKernan, Y. Helbert, L. Kane, N. Houde, L. Zhang, S. McLaughlin, Whole genome sequencing of colonies derived from cannabis flowers & the impact of media selection on benchmarking total yeast & mold detection tools, https://f1000research.com/articles/10-624 (2021).
K. McKernan, Y. Helbert, L. Kane, L. Zhang, N. Houde, A. Bennett, J. Silva, H. Ebling, and S. McLaughlin, Pathogenic Enterobacteriaceae require multiple culture temperatures for detection in Cannabis sativa L. OSF Preprints, https://osf.io/j3msk/, (2022)
In a press release published this week, AOAC International announced it has partnered with Signature Science, LLC as the test material provider for the new AOAC Cannabis/Hemp Proficiency Testing program. What makes this proficiency testing (PT) program so unique is that AOAC will be the only PT provider to offer actual cannabis flower as the matrix.
This month, the pilot round with twenty cannabis testing labs begins with hemp-only samples being shipped in early May. The first live round of the PT program is scheduled for November of this year and will offer participating labs the choice of cannabis flower samples or hemp samples.
The program will include one sample for cannabinoid and terpene profiles, moisture and heavy metals, as well as a second sample for pesticide residue testing. According to the press release, mycotoxins will be added to the mix soon.
The new PT program was developed by stakeholders involved with the AOAC Cannabis Analytical Science Program (CASP), including state regulatory labs, industry labs, state and federal agencies and accreditation bodies. Shane Flynn, senior director of AOAC’s PT program, says the program is a result of scientists coming to them with concerns about testing in the cannabis space. “AOAC has a long history of bringing scientists together to address emerging topics, so when stakeholders came to AOAC with their concerns and need for quality proficiency testing in the cannabis industry, AOAC acted,” says Flynn. “Stakeholders noted the analytical differences in testing cannabis versus hemp and had specific concerns around it and asked for a program that would provide actual cannabis samples in addition to hemp. This is truly a program that was created by the stakeholders, for the stakeholders.”
AOAC says they plan on introducing microbiology to the PT program, with microbial contamination tests in both cannabis and hemp samples. They are also considering adding additional matrices, like chocolate and gummies.
Signature Science is an ISO 17043 accredited proficiency test provider that also has a DEA-licensed controlled substances lab, making them an ideal candidate to partner with AOAC for the PT Program. They entered into a 3-year MoU with AOAC for the program. Their team developed and validated methods used to create the samples for the PT program at their DEA-licensed lab in Austin, Texas.
By Jill Ellsworth MS, RDN, Tess Eidem, Ph.D. No Comments
As an emerging field in cannabis, contaminant testing remains a gray area for many businesses. The vast differences in state-by-state regulations, along with the frequent changes of previously established rules make testing a difficult, time-consuming process. But at its core, the science and reasoning behind why we test cannabis is very clear – consumer safety and quality assurance are key factors in any legal, consumer market. The implications of federal legalization make cannabis testing even more important to the future of the cannabis supply chain. Understanding the types of contaminants, their sources and how to prevent them is essential to avoiding failures, recalls and risking consumer safety.
When talking about cannabis contaminant testing there are four groups of contaminants: pesticides, heavy metals, foreign materials and microbes. The microbes found on cannabis include plant pathogens, post-harvest spoiling microbes, allergens, toxin release and human pathogens. While all of these can be lurking on the surface of cannabis, the specific types that are tested for in each state vary widely. Understanding the full scope of contaminants and looking beyond state-specific compliance requirements, cultivators will be able to prevent these detrimental risks and prepare their business for the future.
Environmental controls are essential to monitor and regulate temperature and humidity
Beyond just the health of the plant, both medical patients and adult use consumers can be adversely affected by microbial contaminants. To immunocompromised patients, Aspergillus can be life-threatening and both adult use and medical consumers are susceptible to allergic reactions to moldy flower. But Aspergillus is just one of the many contaminants that are invisible to the human eye and can live on the plant’s surface. Several states have intensive testing regulations when it comes to the full breadth of possible harmful contaminants. Nevada, for example, has strict microbial testing requirements and, in addition to Aspergillus, the state tests for Salmonella, STEC, Enterobacteriaceae, coliforms and total yeast and mold. Over 15 states test for total yeast and mold and the thresholds vary from allowing less than 100,000 colony forming units to allowing less than 1,000 colony forming units. These microbes are not uncommon appearances on cannabis – in fact, they are ever-present – so understanding them as a whole, beyond regulatory standards is a certain way to future-proof a business. With such vast differences in accepted levels of contamination per state, the best preparation for the future and regulations coming down the pipeline is understanding contamination, addressing it at its source and harvesting disease-free cannabis.
The risk of contamination is present at every stage of the cultivation process and encompasses agricultural practices, manufacturing processes and their intersection. From cultivation to manufacturing, there are factors that can introduce contamination throughout the supply chain. A quality control infrastructure should be employed in a facility and checkpoints within the process to ensure aseptic operations.
Microbial monitoring methods can include frequent/consistent testing
Cultivators should test their raw materials, including growing substrates and nutrient water to ensure it is free of microbial contamination. Air quality plays an important role in the cultivation and post-harvest processes, especially with mold contamination. Environmental controls are essential to monitor and regulate temperature and humidity and ensure unwanted microbes cannot thrive and decrease the value of the product or make it unsafe for worker handling or consumers. Developing SOPs to validate contact surfaces are clean, using proper PPE and optimizing worker flow can all help to prevent cross-contamination and are part of larger quality assurance measures to prevent microbes from spreading across cultivars and harvests.
Methods of microbial examination include air quality surveillance, ATP surface and water monitoring, raw materials testing, and species identification. Keeping control of the environment that product is coming into contact with and employing best practices throughout will minimize the amount of contamination that is present before testing. The solution to avoiding worst case scenarios following an aseptic, quality controlled process is utilizing a safe, post-harvest kill-step, much like the methods used in the food and beverage industries with the oversight of the FDA.
The goal of the grower should be to grow clean and stay clean throughout the shelf life of the product. In order to do this, it is essential to understand the critical control points within the cultivation and post-harvest processes and implement proper kill-steps. However, if a product is heavily bio-burdened, there are methods to recover contaminated product including decontamination, remediation and destroying the product. These measures come with their own strengths and weaknesses and cannot replace the quality assurance programs developed by the manufacturer.
Risk management is the process of identifying potential hazards, assessing the associated risk, then implementing controls to mitigate those risks. With Salmonella and Aspergillus being two of the leading causes of cannabis contamination that can occur throughout the supply chain, applying upstream risk management strategies can keep supplier contamination issues from impacting your products.
Salmonella enteritidis
In recent months cannabis products have been recalled for Salmonella and/or Aspergillus contamination in several states, including California, Arizona, Michigan, Florida, as well as Canada. While the recalls impacted retail products, in most cases, the contamination occurred farther back in the supply chain, as evidenced by recalls that impacted several dispensaries or other sales locations.
For example, the November 2021 Arizona recall caused multiple establishments and dispensaries to recall product due to possible contamination with Salmonella or Aspergillus; the Michigan recall of an estimated $229 million in cannabis products due to “inaccurate and/or unreliable results of products tested.” While a lab lawsuit against the recall released some of the product to market, the companies faced significant impact – in both removing and returning the product.
While microbial contamination can occur throughout the supply chain, Aspergillus is ubiquitous in soil and the flower, leaves, roots of the cannabis plant are all susceptible to such contamination. The mold also can colonize the bud both during growing and harvesting. Salmonella can be introduced during growing through, untreated manures, direct contact with animal feces, or contamination of surface water used for irrigation. However, the plant matter also can be compromised during drying, storage and processing from environmental contamination.
Aspergillus flavus
Supply chain risk management. To prevent a supplier’s contamination issues from becoming your problem to deal with, each facility at each step of the chain should develop a supply chain risk management program to assess and approve each of its upstream providers. Following are 5 key steps to assessing and managing risk in your supply chain:
Conduct a hazard analysis. A complete supply chain assessment should begin with a hazard assessment of all the ingredients, products or primary packaging you receive. There are two essential steps involved in conducting a hazard analysis: that is the identification of potential hazards – considering those related to the item itself, as well as the supplier environment and process as well as item – and an evaluation to determine if each hazard requires control based on its severity and likely occurrence.
Evaluate the risks. Based on the hazard analysis, the next step is to determine the associated risk. As defined by the European Food Information Council (EUFIC), “a hazard is something that has the potential to cause harm while risk is the likelihood of harm taking place, based on exposure to that hazard.” For example, the higher the exposure, the higher the risk.
Ensure risk control. Once risk is determined, it is critical to ensure that it is being controlled, who is controlling it and how it is being done. Depending on the risk, that control may need to be conducted by the supplier, by you or even by a downstream customer.
Require documentation. No matter which step in the chain is controlling the risk, it is essential that all be documented with records easily accessible – including the controls, any out-of-compliance events and corrective actions. The adage, “If it’s not documented, it didn’t happen,” is very applicable here, particularly should a problem arise and an inspector appear at your door.
Use only approved suppliers. Implementation of the above steps enable the development of a supplier approval program focused on quality, safety and regulatory compliance. Use of only suppliers who have been assessed and found to meet all your standards will help to protect your product and your brand.
Salmonella and Aspergillus contamination can occur throughout the supply chain, but implementing a supply chain risk assessment and management program will enable you to determine where the greatest risks lie among your ingredients and suppliers, allowing you to allocate resources based on that risk.
Medicinal Genomics announced today that they have received AOAC International certification for their PathoSEEK® Salmonella and STEC E. coli multiplex assay. In combination with their SenSATIVAx® extraction kits, labs can simultaneously detect Salmonella spp. and STEC E. coli with a single qPCR reaction for flower, concentrates and infused chocolates using the Agilent AriaMx and the BioRad CFx-96 instruments.
The certification came after the multiplex assay was validated according to the AOAC Performance Tested Method Program. According to the press release, the PathoSEEK platform now has more cannabis matrices accredited for Aspergillus, Salmonella, and STEC E. coli than any other product out on the market, according to their press release.
The PathoSEEK microbiological testing platform uses a qPCR assay and internal plant DNA controls for reactions. The two-step protocol verifies performance while detecting microbes, which allegedly helps minimize false negative results from human error or failing conditions.
“AOAC’s validation of our Salmonella/STEC E. coli assay across the various cannabis matrices is further proof of our platform’s robustness and versatility,” says Dr. Sherman Hom, director of regulatory affairs at Medicinal Genomics. “We are excited that our PathoSEEK® platform is moving in concert with the FDA’s new blueprint to improve food safety by modernizing the regulatory framework, while leveraging the use of proven molecular tools to accelerate predictive capabilities, enhance prevention, and enhance our ability to swiftly adapt to pathogen outbreaks that could impact consumer safety.”
As of now, there are only two cannabis testing labs in Connecticut. Last year, regulators in the state approved a request from AltaSci Labs to raise the testing limits for yeast and mold at their lab from 10,000 colony forming units per gram (cfu/g) up to 1 million. The other lab, Northeast Laboratories, has kept their limits at 10,000 cfu/g.
Connecticut state flag
According to CTInsider.com, that request was approved privately and unannounced and patients were notified via email of the change. Ginny Monk at CTInsider says patients enrolled in Connecticut’s medical cannabis program have been outspoken over safety concerns, a lack of transparency and little voice in the decision-making process.
Connecticut has a small medical cannabis market with roughly 54,000 patients in the program and they are in the midst of readying the launch of their adult-use market.
A yeast and mold test showing colony forming units
Following public outcry regarding the change at the recent Social Equity Council meeting, state regulators have proposed a change to microbial testing regulations. The new rule will set the limit at 100,000 cfu/g for yeast and mold and requires testing for specific forms of Aspergillus, a more harmful type of mold.
Kaitlyn Kraddelt, spokeswoman for Connecticut’s Department of Consumer Protection, the agency in charge of testing regulations for the state’s cannabis program, told CTInsider.com that they involved several microbiologists to develop the new rule. “These new standards, which were drafted in consultation with several microbiologists, will prohibit specific types of yeast and mold in cannabis flower that may cause injury when inhaled and allow 10^5 cfu/g of colony forming units that have no demonstrated injurious impact on human health,” says Krasselt.
The rule change is now undergoing a public comment period, after which the Attorney General’s office will get a review period. If approved, it’ll head to the legislature, where a committee has 45 days to act on it.
Increasing cannabis use across the US has come with increased scrutiny of its health effects. Regulators and healthcare providers are not just concerned about the direct effects of inhaling or consuming cannabinoids, however, but also about another health risk: microbial contamination in cannabis products. Like any other crop, cannabis is susceptible to contamination by harmful pathogens at several points throughout the supply chain, from cultivation and harvesting to distribution. Many state regulators have set limits for microbial populations in cannabis products. Consequently, testing labs must adopt efficient screening protocols to help companies remain compliant and keep their customers safe.
Some of the pathogens common to cannabis flower include Aspergillus fungus species such as A. flavus, A. fumigatus, A. niger and A. terreus. Cannabis might also harbor harmful E. coli and Salmonella species, including Shiga toxin-producing E. coli (STEC). Regulations vary by state, but most have set specific thresholds for how many colony forming units (CFUs) of particular species can be present in a sellable product.
The gold standard method for detecting microbes is running cultures.
Growers and testing labs need to develop a streamlined approach to remain viable. Current methods, including running cultures on every sample, can be expensive and time-consuming, but by introducing a PCR-based screening step first, which identifies the presence of microbial DNA – and therefore the potential for contamination – laboratories can reduce the number of cultures they need to run, saving money and time.
The Risk of Aspergillus Contamination
Contamination from Aspergillus species can bring harm to cannabis growers and their customers. The state of Michigan is currently undergoing the largest cannabis recall in its history from Aspergillus contamination.
If contamination grows out of control, the pathogen can damage the cannabis plant itself and lead to financial losses. Aspergillus can also cause serious illness in consumers, especially those that are immunocompromised. If an immunocompromised person inhales Aspergillus, they can develop aspergillosis, a lung condition with a poor prognosis.
A Two-Step Screening Process
The gold standard method for detecting microbes is running cultures. This technique takes weeks to deliver results and can yield inaccurate CFU counts, making it difficult for growers to satisfy regulators and create a safe product in a timely manner. The use of polymerase chain reaction (PCR) can greatly shorten the time to results and increase sensitivity by determining whether the sample has target DNA.
Using PCR can be expensive, particularly to screen for multiple species at the same time, but a qPCR-based Aspergillus detection assay could lead to significant cost savings. Since the average presumptive positive rate for Aspergillus contamination is low (between 5-10%), this assay can be used to negatively screen large volumes of cannabis samples. It serves as an optional tool to further speciate only those samples that screened positive to comply with state regulations.
Conclusion
Overall, screening protocols have become a necessary part of cannabis production, and to reduce costs, testing labs must optimize methods to become as efficient as possible. With tools such as PCR technology and a method that allows for initial mass screening followed by speciation only when necessary, laboratories can release more samples faster with fewer unnecessary analyses and more success for cannabis producers in the marketplace.
bioMérieux, a leader in the in vitro diagnostics space and a supporter of the cannabis testing market, announced last month that they have achieved the first ever AOAC International approval for PCR Multiplex Detection of STEC and Salmonella in cannabis flower for their GENE-UP® PRO STEC/Salmonella Assay. The performance tested method approval for their new assay accomodates simultaneous enrichment and detection of STEC (Shiga Toxigenic Escherichia coli) and Salmonella spp. in cannabis samples.
The method is aimed at increasing efficiency in cannabis testing labs by reducing sample preparation time for microbiological testing. With the single enrichment and real-time multiplex PCR detection, bioMérieux says their new assay can provide reliable detection of STEC and Salmonella in 24 hours using just a single test.
PCR technology is one of the most widely utilized testing methods for detecting pathogens in a variety of matrices. bioMérieux claims it is easy to use, scientifically robust and reduces costs, time spent testing and errors.
Maria McIntyre, cannabis strategic operations business manager at bioMérieux, says that AOAC performance tested method approval is setting the bar for cannabis testing laboratories and furthering cannabis science. “AOAC International impacts cannabis science by setting analytical method standards that act as the benchmark for method validation,” says McIntyre. “This simplifies the validations needed by cannabis laboratories and assures the utmost confidence in product safety and human health.”
Facility layout and design are important components of overall operations, both in terms of maximizing the effectiveness and efficiency of the process(es) executed in a facility, and in meeting the needs of personnel. Prior to the purchase of an existing building or investing in new construction, the activities and processes that will be conducted in a facility must be mapped out and evaluated to determine the appropriate infrastructure and flow of processes and materials. In cannabis markets where vertical integration is the required business model, multiple product and process flows must be incorporated into the design and construction. Materials of construction and critical utilities are essential considerations if there is the desire to meet Good Manufacturing Practice (GMP) compliance or to process in an ISO certified cleanroom. Regardless of what type of facility is needed or desired, applicable local, federal and international regulations and standards must be reviewed to ensure proper design, construction and operation, as well as to guarantee safety of employees.
Materials of Construction
The materials of construction for interior work surfaces, walls, floors and ceilings should be fabricated of non-porous, smooth and corrosive resistant surfaces that are easily cleanable to prevent harboring of microorganisms and damage from chemical residues. Flooring should also provide wear resistance, stain and chemical resistance for high traffic applications. ISO 22196:2011, Measurement Of Antibacterial Activity On Plastics And Other Non-Porous Surfaces22 provides a method for evaluating the antibacterial activity of antibacterial-treated plastics, and other non-porous, surfaces of products (including intermediate products). Interior and exterior (including the roof) materials of construction should meet the requirements of ASTM E108 -11, Standard Test Methods for Fire Tests of Roof Covering7, UL 790, Standard for Standard Test Methods for Fire Tests of Roof Coverings 8, the International Building Code (IBC) 9, the National Fire Protection Association (NFPA) 11, Occupational Safety and Health Administration (OSHA) and other applicable building and safety standards, particularly when the use, storage, filling, and handling of hazardous materials occurs in the facility.
Utilities
Critical and non-critical utilities need to be considered in the initial planning phase of a facility build out. Critical utilities are the utilities that when used have the potential to impact product quality. These utilities include water systems, heating, ventilation and air conditioning (HVAC), compressed air and pure steam. Non-critical utilities may not present a direct risk to product quality, but are necessary to support the successful, compliant and safe operations of a facility. These utilities include electrical infrastructure, lighting, fire detection and suppression systems, gas detection and sewage.
Water
Microbial monitoring methods can include frequent/consistent testing
Water quality, both chemical and microbial, is a fundamental and often overlooked critical parameter in the design phase of cannabis operations. Water is used to irrigate plants, for personnel handwashing, potentially as a component in compounding/formulation of finished goods and for cleaning activities. The United States Pharmacopeia (USP) Chapter 1231, Water for Pharmaceutical Purposes 2, provides extensive guidance on the design, operation, and monitoring of water systems. Water quality should be tested and monitored to ensure compliance to microbiological and chemical specifications based on the chosen water type, the intended use of the water, and the environment in which the water is used. Microbial monitoring methods are described in USP Chapter 61, Testing: Microbial Enumeration Tests3and Chapter 62, Testing: Tests for Specified Microorganisms 4, and chemical monitoring methods are described in USP Chapter 643, Total Organic Carbon 5, and Chapter 645, Water Conductivity6.Overall water usage must be considered during the facility design phase. In addition to utilizing water for irrigation, cleaning, product processing, and personal hygiene, water is used for heating and cooling of the HVAC system, fogging in pest control procedures and in wastewater treatment procedures A facility’s water system must be capable of managing the amount of water required for the entire operation. Water usage and drainage must meet environmental protection standards. State and local municipalities may have water usage limits, capture and reuse requirements and regulations regarding runoff and erosion control that must also be considered as part of the water system design.
Lighting
Lighting considerations for a cultivation facility are a balance between energy efficiency and what is optimal for plant growth. The preferred lighting choice has typically been High Intensity Discharge (HID) lighting, which includes metal halide (MH) and high-pressure sodium (HPS) bulbs. However, as of late, light-emitting diodes (LED) systems are gaining popularity due to increased energy saving possibilities and innovative technologies. Adequate lighting is critical for ensuring employees can effectively and safely perform their job functions. Many tasks performed on the production floor or in the laboratory require great attention to detail. Therefore, proper lighting is a significant consideration when designing a facility.
HVAC
Proper lighting is a significant consideration when designing a facility.
Environmental factors, such as temperature, relative humidity (RH), airflow and air quality play a significant role in maintaining and controlling cannabis operations. A facility’s HVAC system has a direct impact on cultivation and manufacturing environments, and HVAC performance may make or break the success of an operation. Sensible heat ratios (SHRs) may be impacted by lighting usage and RH levels may be impacted by the water usage/irrigation schedule in a cultivation facility. Dehumidification considerations as described in the National Cannabis Industry Association (NCIA) Committee Blog: An Introduction to HVACD for Indoor Plant Environments – Why We Should Include a “D” for Dehumidification 26 are critical to support plant growth and vitality, minimize microbial proliferation in the work environment and to sustain product shelf-life/stability. All of these factors must be evaluated when commissioning an HVAC system. HVAC systems with monitoring sensors (temperature, RH and pressure) should be considered. Proper placement of sensors allows for real-time monitoring and a proactive approach to addressing excursions that could negatively impact the work environment.
Compressed Air
Compressed air is another, often overlooked, critical component in cannabis operations. Compressed air may be used for a number of applications, including blowing off and drying work surfaces and bottles/containers prior to filling operations, and providing air for pneumatically controlled valves and cylinders. Common contaminants in compressed air are nonviable particles, water, oil, and viable microorganisms. Contaminants should be controlled with the use appropriate in-line filtration. Compressed air application that could impact final product quality and safety requires routine monitoring and testing. ISO 8573:2010, Compressed Air Specifications 21, separates air quality levels into classes to help differentiate air requirements based on facility type.
Electrical Infrastructure
Facilities should be designed to meet the electrical demands of equipment operation, lighting, and accurate functionality of HVAC systems. Processes and procedures should be designed according to the requirements outlined in the National Electrical Code (NEC) 12, Institute of Electrical and Electronics Engineers (IEEE) 13, National Electrical Safety Code (NESC) 14, International Building Code (IBC) 9, International Energy Conservation Code (IECC) 15 and any other relevant standards dictated by the Authority Having Jurisdiction (AHJ).
Fire Detection and Suppression
“Facilities should be designed so that they can be easily expanded or adjusted to meet changing production and market needs.”Proper fire detection and suppression systems should be installed and maintained per the guidelines of the National Fire Protection Association (NFPA) 11, International Building Code (IBC) 9, International Fire Code (IFC) 10, and any other relevant standards dictated by the Authority Having Jurisdiction (AHJ). Facilities should provide standard symbols to communicate fire safety, emergency and associated hazards information as defined in NFPA 170, Standard for Fire Safety and Emergency Symbols27.
Gas detection
Processes that utilize flammable gasses and solvents should have a continuous gas detection system as required per the IBC, Chapter 39, Section 3905 9. The gas detection should not be greater than 25 percent of the lower explosive limit/lower flammability limit (LEL/LFL) of the materials. Gas detection systems should be listed and labeled in accordance with UL 864, Standard for Control Units and Accessories for Fire Alarm Systems16 and/or UL 2017, Standard for General-Purpose Signaling Devices and Systems 17 and UL 2075, Standard for Gas and Vapor Detectors and Sensors18.
Product and Process Flow
Product and process flow considerations include flow of materials as well as personnel. The classic product and process flow of a facility is unidirectional where raw materials enter on one end and finished goods exit at the other. This design minimizes the risk of commingling unapproved and approved raw materials, components and finished goods. Facility space utilization is optimized by providing a more streamlined, efficient and effective process from batch production to final product release with minimal risk of errors. Additionally, efficient flow reduces safety risks to employees and an overall financial risk to the organization as a result of costly injuries. A continuous flow of raw materials and components ensures that supplies are available when needed and they are assessable with no obstructions that could present a potential safety hazard to employees. Proper training and education of personnel on general safety principles, defined work practices, equipment and controls can help reduce workplace accidents involving the moving, handling, and storing of materials.
Facilities Management
Facilities management includes the processes and procedures required for the overall maintenance and security of a cannabis operation. Facilities management considerations during the design phase include pest control, preventative maintenance of critical utilities, and security.
Damage from whiteflies, thrips and powdery mildew could be prevented with an appropriate PCP
A Pest Control Program (PCP) ensures that pest and vermin control is carried out to eliminate health risks from pests and vermin, and to maintain the standards of hygiene necessary for the operation. Shipping and receiving areas are common entryways for pests. The type of dock and dock lever used could be a welcome mat or a blockade for rodents, birds, insects, and other vermin. Standard Operating Procedures (SOPs) should define the procedure and responsibility for PCP planning, implementation and monitoring.
Routine preventative maintenance (PM) on critical utilities should be conducted to maintain optimal performance and prevent microbial and/or particulate ingress into the work environment. Scheduled PMs may include filter replacement, leak and velocity testing, cleaning and sanitization, adjustment of airflow, the inspection of the air intake, fans, bearings and belts and the calibration of monitoring sensors.
In most medical cannabis markets, an established Security Program is a requirement as part of the licensing process. ASTM International standards: D8205 Guide for Video Surveillance System 23, D8217 Guide for Access Control System[24], and D8218 Guide for Intrusion Detection System (IDS) 25 provide guidance on how to set up a suitable facility security system and program. Facilities should be equipped with security cameras. The number and location of the security cameras should be based on the size, design and layout of the facility. Additional cameras may be required for larger facilities to ensure all “blind spots” are addressed. The facility security system should be monitored by an alarm system with 24/7 tracking. Retention of surveillance data should be defined in an SOP per the AHJ. Motion detectors, if utilized, should be linked to the alarm system, automatic lighting, and automatic notification reporting. The roof area should be monitored by motion sensors to prevent cut-and-drop intrusion. Daily and annual checks should be conducted on the alarm system to ensure proper operation. Physical barriers such as fencing, locked gates, secure doors, window protection, automatic access systems should be used to prevent unauthorized access to the facility. Security barriers must comply with local security, fire safety and zoning regulations. High security locks should be installed on all doors and gates. Facility access should be controlled via Radio Frequency Identification (RFID) access cards, biometric entry systems, keys, locks or codes. All areas where cannabis raw material or cannabis-derived products are processed or stored should be controlled, locked and access restricted to authorized personnel. These areas should be properly designated “Restricted Area – Authorized Personnel Only”.
Future Expansion
The thought of expansion in the beginning stages of facility design is probably the last thing on the mind of the business owner(s) as they are trying to get the operation up and running, but it is likely the first thing on the mind of investors, if they happen to be involved in the business venture. Facilities should be designed so that they can be easily expanded or adjusted to meet changing production and market needs. Thought must be given to how critical systems and product and process flows may be impacted if future expansion is anticipated. The goal should be to minimize down time while maximizing space and production output. Therefore, proper up-front planning regarding future growth is imperative for the operation to be successful and maintain productivity while navigating through those changes.
References:
United States Environmental Protection Agency (EPA) Safe Drinking Water Act (SDWA).
United States Pharmacopeia (USP) Chapter <1231>, Water for Pharmaceutical Purposes.
United States Pharmacopeia (USP) Chapter <61>, Testing: Microbial Enumeration Tests.
United States Pharmacopeia (USP) Chapter <62>, Testing: Tests for Specified Microorganisms.
United States Pharmacopeia (USP) Chapter <643>, Total Organic Carbon.
United States Pharmacopeia (USP) Chapter <645>, Water Conductivity.
ASTM E108 -11, Standard Test Methods for Fire Tests of Roof Coverings.
UL 790, Standard for Standard Test Methods for Fire Tests of Roof Coverings.
International Building Code (IBC).
International Fire Code (IFC).
National Fire Protection Association (NFPA).
National Electrical Code (NEC).
Institute of Electrical and Electronics Engineers (IEEE).
National Electrical Safety Code (NESC).
International Energy Conservation Code (IECC).
UL 864, Standard for Control Units and Accessories for Fire Alarm Systems.
UL 2017, Standard for General-Purpose Signaling Devices and Systems.
UL 2075, Standard for Gas and Vapor Detectors and Sensors.
International Society for Pharmaceutical Engineers (ISPE) Good Practice Guide.
International Society for Pharmaceutical Engineers (ISPE) Guide Water and Steam Systems.
ISO 8573:2010, Compressed Air Specifications.
ISO 22196:2011, Measurement Of Antibacterial Activity On Plastics And Other Non-Porous Surfaces.
D8205 Guide for Video Surveillance System.
D8217 Guide for Access Control Syst
D8218 Guide for Intrusion Detection System (IDS).
National Cannabis Industry Association (NCIA): Committee Blog: An Introduction to HVACD for Indoor Plant Environments – Why We Should Include a “D” for Dehumidification.
NFPA 170, Standard for Fire Safety and Emergency Symbols.
On August 11, PathogenDx announced that they received an AOAC Performance Tested Methods Certificate for their QuantX total yeast and mold test. Six days later, on August 17, Medicinal Genomics announced that AOAC approved their PathoSEEK 5-Color Aspergillus Multiplex Assays under the same AOAC Performance Tested Methods program.
Both assays are specifically designed with cannabis and hemp testing in mind and designed to expedite and simplify microbiological testing. PathogenDx’s QuantX quantifies the total amount of yeast and mold in a sample while also measuring against safety standards.
In addition to the total yeast and mold count test, PathogenDx has also introduced a 96-well plate, improved sample preparation and new data reporting with a custom reporting portal for compliance testing.
The Medicinal Genomics platform can detect four species, including A. flavus, A. fumigatus, A. niger, and A. terreus in both flower and infused edibles. The PathoSEEK microbial testing platform uses a PCR-based assay and provides an internal plant DNA control for every reaction.
This technique verifies the performance of the assay when detecting pathogens, allegedly minimizing false negative results commonly due to set up errors and experimental conditions.
AOAC International is a standards organization that works in the cannabis testing space through their CASP program to evaluate and approve standard testing methods for the industry.
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