Tag Archives: air

Fungal Monitoring: An Upstream Approach to Testing Requirements

By Bernie Lorenz, PhD
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Mold is ubiquitous in nature and can be found everywhere.1 Cannabis growers know this all too well – the cannabis plant, by nature, is an extremely mold-susceptible crop, and growers battle it constantly.

Of course, managing mold doesn’t mean eradicating mold entirely – that’s impossible. Instead, cultivation professionals must work to minimize the amount of mold to the point where plants can thrive, and finished products are safe for consumption.

Let’s begin with that end in mind – a healthy plant, grown, cured and packaged for sale. In a growing number of states, there’s a hurdle to clear before the product can be sold to consumers – state-mandated testing.

So how do you ensure that the product clears the testing process within guidelines for mold? And what tools can be employed in biological warfare?

Mold: At Home in Cannabis Plants

It helps to first understand how the cannabis plant becomes an optimal environment.

The cannabis flower was designed to capture pollen floating in the air or brought by a pollinating insect.

Photo credit: Steep Hill- a petri dish of mold growth from tested cannabis

Once a mold spore has landed in a flower, the spore will begin to grow. The flower will continue to grow as well, and eventually, encapsulate the mold. Once the mold is growing in the middle of the flower, there is no way to get rid of it without damaging the flower.

A Name with Many Varieties

The types of spores found in or around a plant can make or break whether mold will end with bad product.

Aspergillus for example, is a mold that can produce mycotoxins, which are toxic to humans2. For this reason, California has mandatory testing3for certain aspergillus molds.

Another example, Basidiospores, are found outside, in the air. These are spores released from mushrooms and have no adverse effects on cannabis or a cannabis cultivation facility.

Fungi like powdery mildew and botrytis (PM and Bud Rot) typically release spores in the air before they are physically noticed on plants. Mold spores like these can survive from one harvest to the next – they can be suspended in the air for hours and be viable for years.

How Mold Travels

Different types of spores – the reproductive parts of mold – get released from different types of mold. Similar to plants and animals, mold reproduces when resources are deemed sufficient.

The opposite is also true that if the mold is under enough stress, such as a depleting nutrient source, it can be forced into reproduction to save itself.4

In the end, mold spores are released naturally into the air for many reasons, including physical manipulation of a plant, which, of course, is an unavoidable task in a cultivation facility.5

Trimming Areas: A Grow’s Highest Risk for Mold

Because of the almost-constant physical manipulation of plants that happen inside its walls, a grow’s trimming areas typically have the highest spore counts. Even the cleanest of plants will release spores during trimming.

Best practices include quality control protocols while trimming

These rooms also have the highest risk for cross contamination, since frequently, growers dry flower in the same room as they trim. Plus, because trimming can be labor intensive, with a large number of people entering and leaving the space regularly, spores are brought in and pushed out and into another space.

The Battle Against Mold

The prevalence and ubiquitous nature of mold in a cannabis facility means that the fight against it must be smart, and it must be thorough.

By incorporating an upstream approach to facility biosecurity, cultivators can protect themselves against testing failures and profit losses.

Biosecurity must be all encompassing, including everything from standard operating procedures and proper environmental controls, to fresh air exchange and surface sanitation/disinfection.

One of the most effective tactics in an upstream biosecurity effort is fungal monitoring.

Ways to Monitor Mold

Determining the load or amount of mold that is in a facility is and always will be common practice. This occurs in a few ways.

Post-harvest testing is in place to ensure the safety of consumers, but during the growing process, is typically done using “scouting reports.” A scouting report is a human report: when personnel physically inspect all or a portion of the crop. A human report, unfortunately, can lead to human error, and this often doesn’t give a robust view of the facility mold picture.

Another tool is agar plates. These petri dishes can be opened and set in areas suspected to have mold. Air moves past the plate and the mold spores that are viable land on the dishes. However, this process is time intensive, and still doesn’t give a complete picture.

Alternatively, growers can use spore traps to monitor for mold.

Spore traps draw a known volume of air through a cassette.The inside of the cassette is designed to force the air toward a sticky surface, which is capable of capturing spores and other materials. The cassette is sent to a laboratory for analysis, where they will physically count and identify what was captured using a microscope.

Spore trap results can show the entire picture of a facility’s mold concerns. This tool is also fast, able to be read on your own or sent to a third party for quick and unbiased review. The information yielded is a useful indicator for mold load and which types are prevalent in the facility.

Spore Trap Results: A Story Told

What’s going on inside of a facility has a direct correlation to what’s happening outside, since facility air comes infromthe outside. Thus, spore traps are most effective when you compare a trap inside with one set outside.

When comparing the two, you can see what the plants are doing, view propagating mold, and understand which of the spore types are only found inside.

Similar to its use in homes and businesses for human health purposes, monitoring can indicate the location of mold growth in a particular area within a facility.

These counts can be used to determine the efficacy of cleaning and disinfecting a space, or to find water leaks or areas that are consistently wet (mold will grow quickly and produce spores in these areas).

Using Spore Traps to See Seasonality Changes, Learn CCPs

Utilizing spore traps for regular, facility-wide mold monitoring is advantageous for many reasons.

One example: Traps can help determine critical control points (CCP) for mold.

What does this look like? If the spore count is two times higher than usual, mitigating action needs to take place. Integrated Pest Management (IPM) strategies like cleaning and disinfecting the space, or spraying a fungicide, are needed to bring the spore count down to its baseline.

For example, most facilities will see a spike in spore counts during the times of initial flower production/formation (weeks two to three of the flower cycle).

Seasonal trends can be determined, as well, since summer heat and rain will increase the mold load while winter cold may minimize it.

Using Fungal Monitoring in an IPM Strategy

Fungal monitoring – especially using a spore trap – is a critical upstream step in a successful IPM strategy. But it’s not the only step. In fact, there are five:

  • Identify/Monitor… Using a spore trap.
  • Evaluate…Spore trap results will indicate if an action is needed. Elevated spore counts will be the action threshold, but it can also depend on the type of spores found.
  • Prevention…Avoiding mold on plants using quality disinfection protocols as often as possible.
  • Action…What will be done to remedy the presence of mold? Examples include adding disinfection protocols, applying a fungicide, increasing air exchanges, and adding a HEPA filter.
  • Monitor…Constant monitoring is key. More eyes monitoring is better, and will help find Critical Control Points.

Each step must be followed to succeed in the battle against mold.

Of course, in the battle, there may be losses. If you experience a failed mandatory product testing result, use the data from the failure to fix your facility and improve for the future.

The data can be used to determine efficacy of standard operating procedures, action thresholds, and other appropriate actions. Plus, you can add a spore trap analysis for pre- and post- disinfection protocols, showing whether the space was really cleaned and disinfected after application. This will also tell you whether your products are working.

Leveraging all of the tools available will ensure a safe, clean cannabis product for consumers.


References

  1. ASTM D8219-2019: Standard Guide for Cleaning and Disinfection at a Cannabis Cultivation Center (B. Lorenz): http://www.astm.org/cgi-bin/resolver.cgi?D8219-19
  2. Mycotoxin, Aspergillus: https://www.who.int/news-room/fact-sheets/detail/mycotoxins
  3. State of California Cannabis Regulations: https://cannabis.ca.gov/cannabis-regulations/
  4. Asexual Sporulation in Aspergillus nidulans (Thomas H. Adams,* Jenny K. Wieser, and Jae-Hyuk Yu):  https://pdfs.semanticscholar.org/7eb1/05e73d77ef251f44a2ae91d0595e85c3445e.pdf?_ga=2.38699363.1960083875.1568395121-721294556.1562683339
  5. ASTM standard “Assessment of fungal growth in buildings” Miller, J. D., et al., “Air Sampling Results in Relation to Extent of Fungal Colonization of Building Materials in Some Water Damaged Buildings,” Indoor Air, Vol 10, 2000, pp. 146–151.
  6. Zefon Air O Cell Cassettes: https://www.zefon.com/iaq-sampling-cassettes
Soapbox

California Banned Ozone Generator “Air Purifiers”

By Jeff Scheir
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California was the first state to step up to defend consumers from false marketing claims that ozone generators are safe, effective air purifiers. In reality, ozone is a lung irritant, especially harmful to allergy and asthma sufferers. In 2009, California became the first state in the nation to ban ozone generators. The Air Resources Board of the California Environmental Protection Agency states:

Not all air-cleaning devices are appropriate for use — some can be harmful to human health. The ARB recommends that ozone generators, air cleaners that intentionally produce ozone, not be used in the home or anywhere else humans are present. Ozone is a gas that can cause health problems, including respiratory tract irritation and breathing difficulty.

The regulation took effect in 2009 along with a ban on the sale of air purifiers that emit more than 0.05 parts per million of ozone. The ARB says that anything beyond this is enough to harm human health; however, some experts say that there is no safe level of ozone.

The National Institute for Occupational Safety and Health recommends an exposure limit to ozone of 0.1 ppm and considers levels of 5 ppm or higher “immediately dangerous to life or health.”

If you’re shopping for an air purifier, it’s best to avoid ozone generators, especially if you have a respiratory condition. Ozone generators, and ionic air cleaners that emit ozone, can cause asthma attacks in humans while doing little to nothing to clean the air.

O3 is a free radical, an oxidizer; when it meets any organic molecule floating around it bonds to it and destroys it. In a grow room, organic molecules include the essential oils in cannabis which produce the fragrance. When using ozone within your grow room, too much will not only all but eliminate the smell of your flowers but with prolonged exposure, it begins to actually degrade the cell walls of trichomes and destroy the structure of the glands.

Despite the claims of some manufacturers, ozone does not have an anti-microbial effect in air unless levels far exceed the maximums of the regulation and is therefore harmful humans.

Keeping the grow room clean of mold and bacteria is important, but ozone is not the technology you want to employ to satisfy this goal. Looking into a combination of UVC and Filtration will better meet the goal while keeping both your plants and staff healthy.

Keeping Your Environment Clean: Preventative Measures Against Contamination

By Jeff Scheir
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For years we have heard about and sometimes experienced, white powdery mildew when growing cannabis. It is a problem we can see, and we have numerous ways to combat it. But now more and more states are introducing regulatory testing on our harvests and they are looking for harmful substances like Escherichia coli., Aspergillis Fumigatus, Aspergillis terreus, …  just to name a few. Mycotoxins, mold and bacteria can render a harvest unusable and even unsellable- and you can’t see these problems with the naked eye. How much would it cost you to have to throw away an entire crop?

You bring in equipment to control the humidity. You treat the soil and create just the right amount of light to grow a superior product. You secure and protect the growing, harvesting, drying and production areas of your facility. You do everything you can to secure a superior yield… but do you?

Many of the organisms that can hurt our harvest are being multiplied, concentrated and introduced to the plants by the very equipment we use to control the growing environment. This happens inherently in HVAC equipment.

Your air conditioning equipment cools the air circulating around your harvest in a process that pulls moisture from the air and creates a perfect breeding ground in the wet cooling coil for growth of many of the organisms that can destroy your yield. As these organisms multiply and concentrate in the HVAC system, they then spew out into the very environment you are trying to protect at concentrated levels far greater than outside air. In effect, you are inoculating the very plants you need to keep safe from these toxins if you want to sell your product.

The cannabis industry is starting to take a page from the healthcare and food safety industries who have discovered the best way to mitigate these dangers is the installation of a proper UVC solution inside their air conditioning equipment.

Why? How does UVC help? What is UVC?

What is Ultraviolet?

Ultraviolet (UV) light is one form of electromagnetic energy produced naturally by the sun. UV is a spectrum of light just below the visible light and it is split into four distinct spectral areas – Vacuum UV or UVV (100 to 200 nm), UVC (200 to 280 nm), UVB (280 to 315 nm) and UVA (315 to 400 nm). UVA & UVB have been used in the industry to help promote growth of cannabis.

What is UVC (Ultraviolet C)?

The entire UV spectrum can kill or inactivate many microorganism species, preventing them from replicating. UVC energy at 253.7 nanometers provides the most germicidal effect. The application of UVC energy to inactivate microorganisms is also known as Germicidal Irradiation or UVGI.

UVC exposure inactivates microbial organisms such as mold, bacteria and viruses by altering the structure and the molecular bonds of their DNA (deoxyribonucleic acid). DNA is a “blue print” these organisms use to develop, function and reproduce. By destroying the organism’s ability to reproduce, it becomes harmless since it cannot colonize. After UVC exposure, the organism dies off leaving no offspring, and the population of the microorganism diminishes rapidly.

Ultraviolet germicidal lamps provide a much more powerful and concentrated effect of ultraviolet energy than can be found naturally. Germicidal UV provides a highly effective method of destroying microorganisms.

To better understand how Steril-Aire UVC works, it is important to understand the recommended design. Directed at a cooling coil and drain pan, UVC energy destroys surface biofilm, a gluey matrix of microorganisms that grows in the presence of moisture. Biofilm is prevalent in HVAC systems and leads to a host of indoor air quality (IAQ) and HVAC operational problems. UVC also destroys airborne viruses and bacteria that circulate through an HVAC system and feed out onto the crop. HVAC cooling coils are the largest reservoir and amplification device for microorganisms in any facility.

For the most effective microbial control, UV germicidal Emitters are installed on the supply side of the system, downstream from the cooling coil and above the drain pan. This location provides more effective biofilm and microbial control than in-duct UVC installations. By irradiating the contaminants at the source – the cooling coils and drain pans – UVC delivers simultaneous cleaning of surface microorganisms as well as destruction of airborne microorganisms and mycotoxins. Steril-Aire patented this installation configuration in 1998.

The recirculating air in HVAC systems create redundancy in exposing microorganisms and mycotoxins to UVC, ensuring multiple passes so the light energy is effective against large quantities of airborne mycotoxins and cleaning the air your plants live by.

Where are these mycotoxins coming from?

Aspergillus favors environments with ample oxygen and moisture. Most pre-harvest strategies to prevent these mycotoxins involve chemical treatment and are therefore not ideal for the cannabis industry.

Despite the lack of cannabis protocols and guidelines for reducing mycotoxin contamination, there are some basic practices that can be utilized from other agricultural groups that will help avoid the production of aflatoxins and ochratoxins.

When guidelines are applied correctly to the cannabis industry, the threat of aflatoxin and ochratoxin contamination can be significantly reduced. The place to start is a clean air environment.

Design to win

The design of indoor grow rooms for cannabis is critical to the control of airborne fungal spores and although most existing greenhouses allow for the ingress of fungal spores, experience has shown that they can be retrofitted with air filters, fans, and UVC systems to make them relatively free of these spores. Proper designs have shown clearly that:

  1. Prevention via air and surface disinfection using germicidal UVC is much better than chemical spot treatment on the surface of plants
  2. High levels of air changes per hour enhance UVC system performance in reducing airborne spores
  3. Cooling coil inner surfaces are a hidden reservoir of spores, a fertile breeding ground and constitute an ecosystem for a wide variety of molds. Continuous UVC surface decontamination of all coils should be the first system to be installed in greenhouses to reduce mildew outbreaks.

UVC can virtually eliminate airborne contaminants

Steril-Aire graphic 4

Steril-Aire was the first and is the market leader in using UVC light to eliminate mold and spores to ensure your product will not be ruined or test positive.

  1. Mold and spores grow in your air handler and are present in air entering your HVAC system.
  2. Steril-Aire UVC system installs quickly and easily in your existing system.
  3. The Steril-Aire UVC system destroys up to 99.999% of mold/spores.
  4. Plants are less likely to be affected by mold…with a low cost and no down time solution.

It’s time to protect your harvest before it gets sick. It’s time to be confident your yield will not test positive for the contaminants that will render it unusable. It’s time to win the testing battle. It’s time for a proper UVC solution to be incorporated throughout your facilities.

Why the Central Chiller Isn’t So Central to Grow Room HVAC

By Geoff Brown
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There’s a better way to design HVAC for cannabis grow rooms, and it may seem a little odd at first.

Central chillers are a tried-and-true solution for projects requiring large refrigeration capacity. They’re found in college campuses, hospitals, office buildings and other big facilities.

While central chillers are a good default for most large-scale applications, they fall short in this industry. Grow rooms, with their need for tight, variable conditions and scalable, redundant infrastructure, have HVAC requirements that the central chiller model simply can’t deliver on.

Let’s unpack the shortcomings with the central chiller in this niche and explore some possible solutions.

What’s Wrong With Chillers?

Building a scalable HVAC system is essential for the cannabis industry as it continues to ramp up production in the U.S. and Canada.

Many growers are building their large facilities in phases. In Canada, this is common because growers must have two harvests before they can receive a production permit, so they build just one phase to satisfy this requirement and then build out the facility after the government’s approval.

This strategy of building out is less feasible with a central chiller.

solsticegrowop_feb
Indoor cultivator facilities use high powered lights that give off heat, requiring an efficient air cooling system.

A chiller and its supporting infrastructure are impractical to expand, which means it and the rest of the facility needs to be built to full size for day one, even though the facility will be in partial occupancy for a long time. This results in high upfront capital costs.

If the facility needs to expand later down the road, to meet market demand for example, that will be difficult because, as mentioned, it’s expensive to add capacity to a central chiller.

Additionally, the chiller creates a central point of failure for the facility. When it goes down, crops in every room are at risk of potentially devastating loss. Grow rooms are unusual because of their requirement for strict conditions and even a slight change could have big impact on the crop. Losing control due to mechanical failure could spell disaster.

One Southern Ontario cannabis grower met with some of these issues after constructing their facility, which uses a central chiller for cooling and dehumidification. The chiller was built for full size, but the results were disappointing as early as phase one of cultivation. While sensible demands in the space are being easily met, humidity levels are out of control – flowering rooms are up to 75% RH.

Humidity is one of the most important control aspects to growers. Without a handle on it, growers risk losing their entire crop either because there’s not enough and the plants dry out, or there’s too much and the plants get mold disease. This facility has fortunately not yet reported serious crop issues but is mindful of the potential impact on harvest quality.

By going unitary, capital costs scale on a linear basis.If tight control over humidity is what you need, then a chilled water system needs very careful consideration. That’s because typical chiller system designs get the coils cold enough to lower the air temperature, but not cold enough to condense water out of the air as effectively as a properly designed dehumidifier coil.

A chilled water system capable of achieving the coil temperatures needed for adequate dehumidification in a typical flower room will also require full-time reheat to ensure that air delivered to the plants isn’t shockingly cold — either stunting their growth or killing them altogether. This reheat source adds complexity, cost and inefficiency which does not serve growers well, many of whom are under pressure from both utilities and their management to minimize their energy usage.

How Do Unitary Systems Solve These Problems?

Compared to central chillers, a unitary setup is more agile.

A facility can commence with the minimum capacity it needs for start-up and then add more units in the future as required. They’re usually cheaper to install than a central system and offer several reliability and efficiency benefits as well.

The real business advantage to this approach is to open up the grower’s cash flow by spreading out their costs over time, rather than a large, immediate cost to construct the entire facility and chiller for day one. By going unitary, capital costs scale on a linear basis.

Talltrees
One of the flowering rooms in an indoor set up (Image: Tall Trees LED Company)

Growers can have more control over their crop by installing multiple units to provide varying conditions, room-by-room, instead of a single system that can only provide one condition.

For example, flowering rooms that each have different strains of crop may require different conditions – so they can be served by their own unit to provide variability. Or, rooms that need uniform conditions could just be served by one common unit. The flexibility that growers can enjoy with this approach is nearly unlimited.

Some growers have opted for multiple units installed for the same room, which maximizes redundancy in case one unit fails.

A cannabis facility in the Montreal area went this direction when building their HVAC system. Rather than build everything in one shot, this facility selected a unitary design that had flowering rooms served independently by a series of units, while vegetation rooms shared one. The units were sized to provide more capacity than currently required in each room, which allows the grower to add more plants and lighting in the future if they choose.

This facility expects to build more grow rooms in a future phase, so it was important to have an intelligent system that could accommodate that by being easy to add capacity to. This is accomplished by simply adding more units.Multiple, small systems also have a better return-on-investment.

The grower, after making a significant investment in this facility, was also averse to the risk of losing crop due to mechanical failure, which is why they were happy to go with a system of independent grow room control.

Multiple, small systems also have a better return-on-investment. Not only are they easier to maintain (parts are easier to switch out and downtime for maintenance is minimal) but they can actually be more efficient than a large, central system.

Some units include heat recovery, which recycles the heat created by the dehumidification process to efficiently reheat the unit’s cold discharge air and keep the space temperature consistent, without needing expensive supplementary heaters. There’s also economizer cooling, which can be used to reduce or even eliminate compressor usage during winter by running the unit on dry outside air only.

Demand for cannabis continues to increase and many growers are looking to expand their businesses by adding new facilities or augmenting existing ones. Faced with the limitations of the traditional chiller system, like the lack of flexibility, scalability and redundancy, they’re looking for an intelligent alternative and the unitary approach is earning their trust. It’s expected this option will soon become the leading one across North America.

HACCP

Implementing a HACCP Plan to Address Audit Concerns in the Infused Market

By Daniel Erickson
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HACCP

The increasing appeal and public acceptance of medical and recreational cannabis has increased the focus on the possible food safety hazards of cannabis-infused products. Foodborne illnesses from edible consumption have become more commonplace, causing auditors to focus on the various stages of the supply chain to ensure that companies are identifying and mitigating risks throughout their operations. Hazard Analysis and Critical Control Points (HACCP) plans developed and monitored within a cannabis ERP software solution play an essential role in reducing common hazards in a market currently lacking federal regulation.

What are cannabis-infused products?

Cannabis infusions come in a variety of forms including edibles (food and beverages), tinctures (drops applied in the mouth), sprays (applied under the tongue), powders (dissolved into liquids) and inhalers. Manufacturing of these products resembles farm-to-fork manufacturing processes common in the food and beverage industry, in which best practices for compliance with food safety regulations have been established. Anticipated regulations in the seed-to-sale marketplace and consumer expectations are driving cannabis infused product manufacturers to adopt safety initiatives to address audit concerns.

What are auditors targeting in the cannabis space?

The cannabis auditing landscape encompasses several areas of focus to ensure companies have standard operating procedures (SOP’s) in place. These areas include:

  • Regulatory compliance – meeting state and local jurisdictional requirements
  • Storage and product release – identifying, storing and securing products properly
  • Seed-to-sale traceability –  lot numbers and plant identifiers
  • Product development – including risk analysis and release
  • Accurate labeling –  allergen statements and potency
  • Product sampling – pathogenic indicator and heavy metal testing
  • Water and air quality –  accounting for residual solvents, yeasts and mold
  • Pest control – pesticides and contamination

In addition, auditors commonly access the reliability of suppliers, quality of ingredients, sanitary handling of materials, cleanliness of facilities, product testing and cross-contamination concerns in the food and beverage industry, making these also important in cannabis manufacturers’ safety plans.

How a HACCP plan can help

HACCPWhether you are cultivating, harvesting, extracting or infusing cannabis into edible products, it is important to engage in proactive measures in hazard management, which include a HACCP plan developed by a company’s safety team. A HACCP plan provides effective procedures that protect consumers from hazards inherent in the production and distribution of cannabis-infused products – including biological, chemical and physical dangers. With the lack of federal regulation in the marketplace, it is recommended that companies adopt these best practices to reduce the severity and likelihood of compromised food safety.

Automating processes and documenting critical control points within an ERP solution prevents hazards before food safety is compromised. Parameters determined within the ERP system are utilized for identification of potential hazards before further contamination can occur. Applying best practices historically used by food and beverage manufacturers provides an enhanced level of food safety protocols to ensure quality, consistency and safety of consumables.

Hazards of cannabis products by life-cycle and production stage

Since the identification of hazards is the first step in HACCP plan development, it is important to identify potential issues at each stage. For cannabis-infused products, these include cultivation, harvesting, extraction and edibles production. Auditors expect detailed documentation of HACCP steps taken to mitigate hazards through the entire seed-to-sale process, taking into account transactions of cannabis co-products and finished goods at any stage.

Cultivation– In this stage, pesticides, pest contamination and heavy metals are of concern and should be adequately addressed. Listeria, E. coli, Salmonella and other bacteria can also be introduced during the grow cycle requiring that pathogenic indicator testing be conducted to ensure a bacteria-free environment.

Harvesting– Yeast and mold (aflatoxins) are possible during the drying and curing processes. Due to the fact that a minimal amount of moisture is optimal for prevention, testing for water activity is essential during harvesting.

Extraction – Residual solvents such as butane and ethanol are hazards to be addressed during extraction, as they are byproducts of the process and can be harmful. Each state has different allowable limits and effective testing is a necessity to prevent consumer exposure to dangerous chemical residues.

Edibles– Hazards in cannabis-infused manufacturing are similar to other food and beverage products and should be treated as such. A risk assessment should be completed for every ingredient (i.e. flour, eggs, etc.), with inherent hazards or allergens identified and a plan for addressing approved supplier lists, obtaining quality ingredients, sanitary handling of materials and cross-contamination.

GMPFollowing and documenting the HACCP plan through all of the stages is essential, including a sampling testing plan that represents the beginning, middle and end of each cannabis infused product. As the last and most important step before products are introduced to the market, finished goods testing is conducted to ensure goods are safe for consumption. All information is recorded efficiently within a streamlined ERP solution that provides real-time data to stakeholders across the organization.

Besides hazards that are specific to each stage in the manufacturing of cannabis-infused products, there are recurring common procedures throughout the seed-to-sale process that can be addressed using current Good Manufacturing Practices (cGMP’s).  cGMPs provide preventative measures for clean work environments, training, establishing SOPs, detecting product deviations and maintaining reliable testing. Ensuring that employees are knowledgeable of potential hazards throughout the stages is essential.Lacking, inadequate or undocumented training in these areas are red flags for auditors who subscribe to the philosophy of “if it isn’t documented, it didn’t happen.” Training, re-training (if necessary) and documented information contained within cannabis ERP ensures that companies are audit-ready. 

Labeling

The importance of proper labeling in the cannabis space cannot be understated as it is a key issue related to product inconsistency in the marketplace. Similar to the food and beverage industry, accurate package labeling, including ingredient and allergen statements, should reflect the product’s contents. Adequate labeling to identify cannabis products and detailed dosing information is essential as unintentional ingestion is a reportable foodborne illness. Integrating an ERP solution with quality control checks and following best practices ensures product labeling remains compliant and transparent in the marketplace.

Due to the inherent hazards of cannabis-infused products, it’s necessary for savvy cannabis companies to employ the proper tools to keep their products and consumers safe. Utilizing an ERP solution that effectively manages HACCP plans meets auditing requirements and helps to keep cannabis operations one step ahead of the competition.

Total Yeast & Mold Count: What Cultivators & Business Owners Need to Know

By Parastoo Yaghmaee, PhD
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Editor’s note: This article should serve as a foundation of knowledge for yeast and mold in cannabis. Beginning in January 2018, we will publish a series of articles focused entirely on yeast and mold, discussing topics such as TYMC testing, preventing yeast and mold in cultivation and treatment methods to reduce yeast and mold.


Cannabis stakeholders, including cultivators, extractors, brokers, distributors and consumers, have been active in the shadows for decades. With the legalization of recreational adult use in several states, and more on the way, safety of the distributed product is one of the main concerns for regulators and the public. Currently, Colorado1, Nevada and Canada2 require total yeast and mold count (TYMC) compliance testing to evaluate whether or not cannabis is safe for human consumption. As the cannabis industry matures, it is likely that TYMC or other stringent testing for yeast and mold will be adopted in the increasingly regulated medical and recreational markets.

The goal of this article is to provide general information on yeast and mold, and to explain why TYMC is an important indicator in determining cannabis safety.

Yeast & Mold

Photo credit: Steep Hill- a petri dish of mold growth from tested cannabis

Yeast and mold are members of the fungi family. Fungus, widespread in nature, can be found in the air, water, soil, vegetation and in decaying matter. The types of fungus found in different geographic regions vary based upon humidity, soil and other environmental conditions. In general, fungi can grow in a wide range of pH environments and temperatures, and can survive in harsh conditions that bacteria cannot. They are not able to produce their own food like plants, and survive by breaking down material from their surroundings into nutrients. Mold cannot thrive in an environment with limited oxygen, while yeast is able to grow with or without oxygen. Most molds, if grown for a long enough period, can be detected visually, while yeast growth is usually detected by off-flavor and fermentation.

Due to their versatility, it is rare to find a place or surface that is naturally free of fungi or their spores. Damp conditions, poor air quality and darker areas are inviting environments for yeast and mold growth.

Cannabis plants are grown in both indoor and outdoor conditions. Plants grown outdoors are exposed to wider ranges and larger populations of fungal species compared to indoor plants. However, factors such as improper watering, the type of soil and fertilizer and poor air circulation can all increase the chance of mold growth in indoor environments. Moreover, secondary contamination is a prevalent risk from human handling during harvest and trimming for both indoor and outdoor-grown cannabis. If humidity and temperature levels of drying and curing rooms are not carefully controlled, the final product could also easily develop fungi or their growth by-product.

 What is TYMC?

TYMC, or total yeast and mold count, is the number of colony forming units present per gram of product (CFU/g). A colony forming unit is the scientific means of counting and reporting the population of live bacteria or yeast and mold in a product. To determine the count, the cannabis sample is plated on a petri dish which is then incubated at a specific temperature for three to five days. During this time, the yeast and mold present will grow and reproduce. Each colony, which represents an individual or a group of yeast and mold, produces one spot on the petri dish. Each spot is considered one colony forming unit.

Why is TYMC Measured?

TYMC is an indicator of the overall cleanliness of the product’s life cycle: growing environment, processing conditions, material handling and storage facilities. Mold by itself is not considered “bad,” but having a high mold count, as measured by TYMC, is alarming and could be detrimental to both consumers and cultivators. 

Aspergillus species niger
Photo: Carlos de Paz, Flickr

The vast majority of mold and yeast present in the environment are indeed harmless, and even useful to humans. Some fungi are used commercially in production of fermented food, industrial alcohol, biodegradation of waste material and the production of antibiotics and enzymes, such as penicillin and proteases. However, certain fungi cause food spoilage and the production of mycotoxin, a fungal growth by-product that is toxic to humans and animals. Humans absorb mycotoxins through inhalation, skin contact and ingestion. Unfortunately, mycotoxins are very stable and withstand both freezing and cooking temperatures. One way to reduce mycotoxin levels in a product is to have a low TYMC.

Aspergillus flavus on culture.
Photo: Iqbal Osman, Flickr

Yeast and mold have been found to be prevalent in cannabis in both current and previous case studies. In a 2017 UC Davis study, 20 marijuana samples obtained from Northern California dispensaries were found to contain several yeast and mold species, including Cryptococcus, Mucor, Aspergillus fumigatus, Aspergillus niger, and Aspergillus flavus.3 The same results were reported in 1983, when marijuana samples collected from 14 cannabis smokers were analyzed. All of the above mold species in the 2017 study were present in 13 out of 14 marijuana samples.4

Aspergillus species niger, flavus, and fumigatus are known for aflatoxin production, a type of dangerous mycotoxin that can be lethal.5 Once a patient smokes and/or ingests cannabis with mold, the toxins and/or spores can thrive inside the lungs and body.6, 7 There are documented fatalities and complications in immunocompromised patients smoking cannabis with mold, including patients with HIV and other autoimmune diseases, as well as the elderly.8, 9, 10, 11

For this reason, regulations exist to limit the allowable TYMC counts for purposes of protecting consumer safety. At the time of writing this article, the acceptable limit for TYMC in cannabis plant material in Colorado, Nevada and Canada is ≤10,000 CFU/g. Washington state requires a mycotoxin test.12 California is looking into testing for specific Aspergillus species as a part of their requirement. As the cannabis industry continues to grow and advance, it is likely that additional states will adopt some form of TYMC testing into their regulatory testing requirements.

References:

  1. https://www.colorado.gov/pacific/sites/default/files/Complete%20Retail%20Marijuana%20Rules%20as%20of%20April%2014%202017.pdf
  2. http://laws-lois.justice.gc.ca/eng/acts/f-27/
  3. https://www.ucdmc.ucdavis.edu/publish/news/newsroom/11791
  4. Kagen SL, Kurup VP, Sohnle PG, Fink JN. 1983. Marijuana smoking and fungal sensitization. Journal of Allergy & Clinical Immunology. 71(4): 389-393.
  5. Centre for Disease control and prevention. 2004 Outbreak of Aflatoxin Poisoning – Eastern and central provinces, Kenya, Jan – July 2004. Morbidity and mortality weekly report.. Sep 3, 2004: 53(34): 790-793
  6. Cescon DW, Page AV, Richardson S, Moore MJ, Boerner S, Gold WL. 2008. Invasive pulmonary Aspergillosis associated with marijuana use in a man with colorectal cancer. Diagnosis in Oncology. 26(13): 2214-2215.
  7. Szyper-Kravits M, Lang R, Manor Y, Lahav M. 2001 Early invasive pulmonary aspergillosis in a leukemia patient linked to aspergillus contaminated marijuana smoking. Leukemia Lymphoma 42(6): 1433 – 1437.
  8. Verweii PE, Kerremans JJ, Voss A, F.G. Meis M. 2000. Fungal contamination of Tobacco and Marijuana. JAMA 2000 284(22): 2875.
  9. Ruchlemer R, Amit-Kohn M, Raveh D, Hanus L. 2015. Inhaled medicinal cannabis and the immunocompromised patient. Support Care Cancer. 23(3):819-822.
  10. McPartland JM, Pruitt PL. 1997. Medical Marijuana and its use by the immunocompromised. Alternative Therapies in Health and Medicine. 3 (3): 39-45.
  11. Hamadeh R, Ardehali A, Locksley RM, York MK. 1983. Fatal aspergillosis associated with smoking contaminated marijuana, in a marrow transplant recipient. Chest. 94(2): 432-433.
  12. http://apps.leg.wa.gov/wac/default.aspx?cite=314-55-102