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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.

Water Policy in California: Six Key Takeaways from the State Water Board’s New Cannabis Cultivation Policy

By Amy Steinfeld
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Cannabis is the most highly regulated crop in California, and the state just added another layer of regulation. This article breaks down the State Water Resources Control Board’s (SWRCB) recently updated Cannabis Cultivation Policy – Principles and Guidelines for Cannabis Cultivation (“Policy”) into six key takeaways.1 These guidelines impose new rules on cannabis cultivation activities that have the potential to impact a watercourse (stream, creek, river or lake). Most of these rules apply to cultivation of sun-grown cannabis, which is currently allowed in some form in 12 counties. Compliance with these new requirements will be implemented through the CalCannabis Cultivation Licensing Program.

  1. When developing farmland, hillsides should be avoided and erosion must be controlled.

The Policy provides specific rules for growing pot on undisturbed land. To prevent erosion, numerous limitations are placed on earthmoving and activities in sensitive areas, and cultivators are not allowed to grade hillsides that exceed a 50% slope.2

Cultivation prepping activities must minimize grading, dust, soil disturbance, erosion, and impacts on habitat, especially during the winter season.3 No vehicles or heavy equipment may be used within a riparian setback4 or watercourse,5 and cultivators must avoid damaging native riparian vegetation6 and oak woodlands.7 All farm equipment, fuel, and hazardous materials must be carefully stored away from creeks and sensitive habitat.8 The Policy also governs road construction.9

  1. Cultivators should avoid work in or near a surface waterbody.10

If a cultivator’s activities impact a river, stream, or lake, they must consult with the California Department of Fish and Wildlife (CDFW).11 Cultivators must maintain minimum riparian setbacks for all cannabis activities, including grading and ancillary farm facilities. Before grading land, a biologist must identify any sensitive flora or fauna, and if any is located, consult with CDFW and provide a report to the Regional Board.12 No irrigation runoff, tailwater, chemicals or plant waste can be discharged to a waterbody.13 Diversion facilities for the irrigation of cannabis may not block fish passage, upstream or downstream, and must be fitted with a CDFW-approved fish screen; new facilities are subject to all applicable permits and approvals.

  1. During the dry season, cultivators may not use surface water.

The use of surface water supplies in California requires a valid water right and the use of water for cannabis cultivation is no different.14 Anyone seeking to appropriate “water flowing in a known and defined channel” or from a watercourse must apply to the SWRCB and obtain a permit or license.15 Alternatively, a landowner whose property is adjacent to a watercourse may have a riparian right to divert the water for use on her land. Riparian users do not need permission from the SWRCB to divert water, but they must report water use annually.16

The biggest obstacle that growers face under this Policy is that they cannot divert anysurface water during the dry season—the growing season (April 1 through Oct. 31). It should be noted:

  • The seasonal prohibition of surface water diversion applies regardless of the nature of the water right or what has been historically used to irrigate other crops.
  • During the dry period, cultivators may only irrigate using stored water (see no. 5 below) or groundwater.
  • It remains to be seen whether a legal challenge will be brought against the state for their draconian prohibitions on irrigating cannabis during the six-month growing season. Because this prohibition applies to all watersheds in California, singles out one low-water use crop, and ignores established water rights, it is overly broad and may constitute a constitutional “taking” of property rights.
  1. During the wet season, surface water diversions must be monitored closely.

Cannabis-specific restrictions also apply during the wet season. From Nov. 1 to March 31, cultivators must comply with instream flow requirements and check in with the state daily. All surface water diversions for cannabis are subject to “Numeric and Narrative Instream Flow Requirements,” to protect flows needed for fish migration and spawning. To ensure diversions do not adversely impact fish flows, cultivators must also “maintain a minimum bypass of at least 50% of the streamflow.”17,18

While valid appropriative right holders may divert more than 10 gal./min. for cannabis irrigation during the wet season, riparian right holders are not allowed to exceed that diversion rate.19 All cultivators (including small diverters <10 acre-feet (“AF”)/yr) are required to employ water-saving irrigation methods, install measuring devices to track diversions daily, and maintain records on-site for at least five years.20 Cultivators must inspect and repair their water delivery system for leaks monthly,21 and inspect sprinklers and mainlines weekly to prevent runoff.22

  1. Cannabis cultivators may obtain a new water storage right for use during the dry season.

To address dry season irrigation limitations, cultivators are urged to store water offstream during the wet season, including rainwater, for dry season use. Growers may not rely on onstreamstorage reservoirs, except if they have an existing permitted reservoir in place prior to Oct. 31, 2017.23 Alternatively, small growers (storage is capped at 6.6 AF/yr) may benefit from the new Cannabis SIUR Program, an expedited process for cultivators who divert from a surface water source to develop and install storage offstream. Only diverters with a valid water right that allows for diversion to storage between Nov. 1 and March 31 qualify.

  1. Groundwater is less regulated, but cultivators should avoid drilling or using wells near waterbodies.

Groundwater is generally the recommended water supply for cannabis because, unlike surface water, it may be used during the dry season and is not subject to many of the restrictions listed above. It should be noted however:

  • Many groundwater basins are now governed by California’s Sustainable Groundwater Management Act (“SGMA”), which requires water agencies to halt overdraft and restore balanced levels of groundwater pumping from certain basins. Thus, SGMA may result in future pumping cutbacks or pumping assessments.
  • In some counties, moratoriums and restrictions on drilling new wells are on the rise.
  • Under this Policy, the state may step in to restrict groundwater pumping in the dry season in watersheds where there are large numbers of cannabis groundwater, wells located close to streams, and areas of high surface water-groundwater connectivity.24

In short, groundwater pumpers are at risk of cutback if the state deems it necessary to maintain nearby creek flows.Noncompliance can bring lofty fines, revocation of a grower’s cultivation license, or prosecution

Final Takeaways

This cannabis policy presents one of California’s most complex regulatory schemes to date. Before investing in a property, one must understand this Policy and have a robust understanding of the water rights and hydrology associated with the cultivation site. Growers looking to reduce permitting time and costs should invest in relatively flat, historically cultivated land with existing wells and ample groundwater supplies, or alternatively, grow indoors.

This article attempts to synthesize the maze of water supply and water quality regulations that make compliance exceedingly difficult; more detailed information can be found here. Noncompliance can bring lofty fines, revocation of a grower’s cultivation license, or prosecution. Growers are encouraged to contact a hydrologist and water lawyer before making major investments and to designate a water compliance officer to monitor and track all water diversions and water used for irrigation. Growers should also consult with their local jurisdiction regarding water use restrictions and stream setbacks before moving any dirt or planting cannabis.

References

  1. The Policy is available at: https://www.waterboards.ca.gov/water_issues/programs/cannabis/cannabis_policy.html (will go into effect on or before April 16, 2019.)
  2. Policy, Appendix A, Section 2, Term 4. The Policy defines “Qualified Professional” as a: California-Licensed Professional Geologist, including Certified Hydrogeologist and Certified Engineering Geologist, California-Licensed Geotechnical Engineer, and Professional Hydrologist. (Policy, Definition 72, p. 11.)
  3. Policy, Appendix A, Section 2, Terms 4 and 10.
  4. Policy, Appendix A, Section 2, Term 3.
  5. Policy, Appendix A, Section 2, Term 40.
  6. Policy, Appendix A, Section 2, Term 33.
  7. Policy, Appendix A, Section 2, Term 34.
  8. Policy, Appendix A, Section 2, Term 7.
  9. Policy, Appendix A, Section 2, Terms 15 to 29.
  10. Policy, Appendix A, Section 1, Term No. 41.
  11. Policy, Appendix A, Section 1, Term No. 3; see also 1602.
  12. Policy, Appendix A, Section 1, Term No. 10.
  13. Policy, Appendix A, Section 1, Term No. 326.
  14. Policy, Appendix A, Section 2, Term 69.
  15. Wat. Code §1225; See alsoWat. Code §1201 [providing that the state shall have jurisdiction over, “[a]ll water flowing in any natural channel” except water that is appropriated or being used for beneficial purpose upon land riparian to the channel.”]
  16. Wat. Code §§ 5100–02.
  17. Policy, p. 12.
  18. Policy, Attachment A, pp. 60, 63.
  19. Policy, Section 2, Term 78.
  20. Policy, Section 2, Term 82.
  21. Policy, Section 2, Term 95.
  22. Policy, Section 2, Term 99.
  23. Policy, Section 2, Term 79.
  24. Policy, p. 11.

Heavy Metals Testing: Methods, Strategies & Sampling

By Charles Deibel
3 Comments

Editor’s Note: The following is based on research and studies performed in their Santa Cruz Lab, with contributions from Mikhail Gadomski, Lab Manager, Ryan Maus Technical Services Analyst, Laurie Post, Director of Food Safety & Compliance, and Charles Deibel, President Deibel Cannabis Labs.

Heavy metals are common environmental contaminants resulting from human industrial activities such as mining operations, industrial waste, automotive emissions, coal fired power plants and farm/house hold water run-off. They affect the water and soil, and become concentrated in plants, animals, pesticides and the sediments used to make fertilizers. They can also be present in low quality glass or plastic packaging materials that can leach into the final cannabis product upon contact. The inputs used by cultivators that can be contaminated with heavy metals include fertilizers, growing media, air, water and even the clone/plant itself.

The four heavy metals tested in the cannabis industry are lead, arsenic, mercury and cadmium. The California Bureau of Cannabis Control (BCC) mandates heavy metals testing for all three categories of cannabis products (inhalable cannabis, inhalable cannabis products and other cannabis and cannabis products) starting December 31, 2018. On an ongoing basis, we recommend cultivators test for the regulated heavy metals in R&D samples any time there are changes in a growing process including changes to growing media, cannabis strains, a water system or source, packaging materials and fertilizers or pesticides. Cultivators should test the soil, nutrient medium, water and any new clones or plants for heavy metals. Pre-qualifying a new packaging material supplier or a water source prior to use is a proactive approach that could bypass issues with finished product.

Testing Strategies

The best approach to heavy metal detection is the use of an instrument called an Inductively Coupled Plasma Mass Spectrometry (ICP-MS). There are many other instruments that can test for heavy metals, but in order to achieve the very low detection limits imposed by most states including California, the detector must be the ICP-MS. Prior to detection using ICP-MS, cannabis and cannabis related products go through a sample preparation stage consisting of some form of digestion to completely break down the complex matrix and extract the heavy metals for analysis. This two-step process is relatively fast and can be done in a single day, however, the instruments used to perform the digestion are usually the limiting step as the digesters run in a batch of 8-16 samples over a 2-hour period.

Only trace amounts of heavy metals are allowed by California’s BCC in cannabis and cannabis products. A highly sensitive detection system finds these trace amounts and also allows troubleshooting when a product is found to be out of specification.

For example, during the course of testing, we have seen lead levels exceed the BCC’s allowable limit of 0.5 ppm in resin from plastic vape cartridges. An investigation determined that the plastic used to make the vape cartridge was the source of the excessive lead levels. Even if a concentrate passes the limits at the time of sampling, the concern is that over time, the lead leached from the plastic into the resin, increasing the concentration of heavy metals to unsafe levels.

Getting a Representative Sample

The ability to detect trace levels of heavy metals is based on the sample size and how well the sample represents the entire batch. The current California recommended amount of sample is 1 gram of product per batch.  Batch sizes can vary but cannot be larger than 50 pounds of flower. There is no upper limit to the batch sizes for other inhalable cannabis products (Category II).

It is entirely likely that two different 1 gram samples of flower can have two different results for heavy metals because of how small a sample is collected compared to an entire batch. In addition, has the entire plant evenly collected and concentrated the heavy metals into every square inch of it’s leaves? No, probably not. In fact, preliminary research in leafy greens shows that heavy metals are not evenly distributed in a plant. Results from soil testing can also be inconsistent due to clumping or granularity. Heavy metals are not equally distributed within a lot of soil and the one small sample that is taken may not represent the entire batch. That is why it is imperative to take a “random” sample by collecting several smaller samples from different areas of the entire batch, combining them, and taking a 1 g sample from this composite for analysis.

References

California Cannabis CPA. 12/18/2018.  “What to Know About California’s Cannabis Testing Requirements”. https://www.californiacannabiscpa.com/blog/what-to-know-about-californias-cannabis-testing-requirements. Accessed January 10, 2019.

Citterio, S., A. Santagostino, P. Fumagalli, N. Prato, P. Ranalli and S. Sgorbati. 2003.  Heavy metal tolerance and accumulation of Cd, Cr and Ni by Cannabis sativa L.. Plant and Soil 256: 243–252.

Handwerk, B. 2015.  “Modern Marijuana Is Often Laced With Heavy Metals and Fungus.” Smithsonian.com. https://www.smithsonianmag.com/science-nature/modern-marijuana-more-potent-often-laced-heavy-metals-and-fungus-180954696/

Linger, P.  J. Mussig, H. Fischer, J. Kobert. 2002.  Industrial hemp (Cannabis sativa L.) growing on heavy metal contaminated soil: fibre quality and phytoremediation potential. Ind. Crops Prod. 11, 73–84.

McPartland, J. and K. J McKernan. 2017.  “Contaminants of Concern in Cannabis: Microbes, Heavy Metals and Pesticides”.  In: S. Chandra et al. (Eds.) Cannabis sativa L. – Botany and Biotechnology.  Springer International Publishing AG. P. 466-467.  https://www.researchgate.net/publication/318020615_Contaminants_of_Concern_in_Cannabis_Microbes_Heavy_Metals_and_Pesticides.  Accessed January 10, 2019.

Sidhu, G.P.S.  2016.  Heavy metal toxicity in soils: sources, remediation technologies and challenges.   Adv Plants AgricRes. 5(1):445‒446.

Seven Steps To Avoid the Green Rush Blues: Investigate Water Supplies Before Planting Cannabis

By Amy M. Steinfeld
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A clean, reliable water supply lies at the heart of every successful cannabis farm. It’s no surprise that the stakes for finding land with ideal growing conditions, including adequate water, are high. But new buyers (and lessees) caught up in the green rush often gloss over water rights or are unaware of California’s byzantine rules governing the irrigation of cannabis.

Water rights are complex. Water regulations applicable to cannabis cultivation are even more complex. And our new climate reality convolutes things further. Longer droughts, more volatile weather, political uncertainties, increased groundwater regulation and water quality concerns are exacerbating tensions over local and statewide water supplies. In many areas of California, landowners can no longer rely on local water districts to meet their needs.

A robust investigation of the property must consider water supplies. Because a property’s water supply is dependent on water rights, local ordinances, state regulations, politics and hydrology, it’s important to consult a water lawyer (and in some instances a hydrologist) before closing. A bit of foresight can prevent a grower from being left high and dry.

The following checklist provides a roadmap to conduct water rights’ due diligence. While many of these details are California-specific, this type of due diligence applies throughout the West.

Step 1: Identify Available Water Supplies and Consider Potential Limitations On Irrigation, Including Potential Future Changes

Conduct a site visit to identify existing water infrastructure, natural water features and existing or potential water service options. Next, determine if the property is served by a public water supplier. If that’s the case, the California State Water Resources Control Board (“State Water Board”) does not require any specific documentation to irrigate cannabis, but the water supply must be disclosed in the CalCannabis license application.

Groundwater is generally the best supply for cannabis, but the era of unregulated groundwater pumping is over. Many groundwater basins in California are now governed by the Sustainable Groundwater Management Act (“SGMA”), which requires water agencies to halt overdraft and restore balanced levels of groundwater pumping from certain basins. As a result, SGMA may result in future pumping cutbacks or pumping assessments. It’s imperative to identify the local groundwater basin via the Department of Water Resources’ Bulletin 118, and determine whether the groundwater basin is adjudicated or governed by a groundwater sustainability agency. Growers should also test the local water supply’s pH and salt levels because cannabis plants are finicky and water treatment can be cost prohibitive. If a new well is needed, growers should consult with their local county before drilling a new well. In some areas, moratoriums and restrictions on drilling new wells are on the rise.

As a rule of thumb, cannabis cultivators should avoid using surface water to irrigate cannabis. Surface diversions are subject to the California Department of Fish and Wildlife’s permitting authority. And under the interim State Water Board Cannabis Policy, commercial cannabis cultivators cannot divert anysurface water during the dry season (April 1 through Oct. 31), even if they have a riparian right that can be used to irrigate other crops. During the dry season, cultivators may only irrigate using water that has been stored off-stream. And even during the wet season, cannabis cultivators must comply with instream flow requirements and check in with the state daily to ensure adequate water supplies are available. Cannabis cultivators are also required to install measuring devices and track surface water diversions daily. And buyer beware, a groundwater well that extracts water from a subterranean stream may be considered a surface-water diversion. So be especially cautious if the well is located close to a creek or river.Develop a water use plan to optimize water efficiency 

Step 2: Identify Water Supplies Used On the Property, Including the Basis of Right, and Quantify Historical Use

Review information on historic and existing water use. This may include past water bills and assessments. If there is a well on the property, the seller or lessor may have metering data, electrical records and crop data that can establish historic groundwater use. Cultivators must submit a well log to CalCannabis as part of the cannabis cultivation application. If surface water is available, the purchaser should review the State Water Board eWRIMs database for water rights permits, licenses, stock pond registrations and certificates, decisions and orders. The purchaser should also identify surface water diversion structures and review annual filings to determine compliance with all terms and conditions of the water right. Lastly, the purchaser should request all documents and contracts pertaining to water rights.

Realistically estimate water demand for irrigation and other on-site purposes.Step 3: Confirm Ownership of Right and Assess Any Limitations On Water Right

Determine whether the right has been abandoned, lost to prescription or forfeited. Evaluate the seniority of the water right, availability of the right, adequacy of place of use, purpose of use (must include irrigation), season of use, and quantity of any permitted or licensed post-1914 right. Determine whether historical diversions pursuant to an appropriative right support the full amount of the claimed right, and whether any changes to the water right are needed to support the proposed new use. Cultivators in California who plan to utilize surface water also need to file for a “Cannabis Small Irrigation Use Registration” to store water during the wet season for use during the dry season.

Step 4: Reconcile Water Demand With Available Supply

Realistically estimate water demand for irrigation and other on-site purposes. Develop a water use plan to optimize water efficiency (drip irrigation, rainwater harvesting, water monitoring, hoop structures) regardless of supply sufficiency. Many counties, such as Santa Barbara County, require that cannabis growers meet certain irrigation efficiency standards. Determine whether available supplies can meet all proposed demands, including plans for full buildout. If not, consider whether additional supplies are available for use on the property.

Step 5: Determine Water Supply Compliance Obligations

 The rights associated with water supplies are defined by their source, the time frame during which supplies can be taken, the quantity of water to which the right attaches, and any limitations on the purpose of use of the water supply. There may also be reporting requirements associated with taking and using the supply—these can include requirements to report the quantity of water used as well as information regarding the end use of the water. Failure to timely report can have serious consequences. Cannabis cultivators are also subject to additional water quality regulations and restrictions, including waste discharge requirements pursuant to the State Water Board’s Cannabis General Order.

Step 6: Negotiate Deal and Draft Conveyance Documents

After obtaining an understanding of the water supply associated with the property, the property conveyance documents may be drafted to incorporate the transfer of rights associated with the property’s water supplies. These may include the assignment of contracts pursuant to which water supplies are obtained, the transfer of permits or licenses as to the water supplies, or the transfer of water rights arising out of a judgment or decree.

Step 7: Consider Unused Water Supply Assets That Could Be Monetized 

To the extent the water supply rights associated with the property exceed the cannabis plants’ water demand, it may be possible to monetize unused or excess water supply assets through transfer of the rights to a third party.

If you have any questions about water rights related to cannabis cultivation it’s always in your best interest to contact an experienced water attorney early on in the process.

Image 2: Temperature display provides quick view of sensor data

10 Questions To Ask Before Installing a Remote Monitoring System

By Rob Fusco
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Image 2: Temperature display provides quick view of sensor data

No matter the size of your cannabis greenhouse operation, keeping your plants alive and healthy requires the best possible growing environment. This means greenhouse managers and personnel must frequently monitor the status of environmental conditions and equipment. The sooner someone discovers extreme temperature fluctuations, rising humidity or equipment failure, the more inventory you can save.

Image 1: Cloud-based remote monitoring system in protective enclosure
Cloud-based remote monitoring system in protective enclosure

That’s why integrating a remote monitoring system into your greenhouse operation can save you time, money and anxiety. Monitoring systems that use cloud-based technology let you see real-time status of all monitored conditions and receive alerts right on your mobile device.

Installing a monitoring system and sensors can be easier than you might think. Here are answers to ten questions to ask before installing a cloud-based monitoring system:

  1. What is required to use a remote monitoring system?

Most remote monitoring systems require an internet or WiFi connection and access to an electrical outlet. Programming is done through a website, so it’s easiest to use a computer for the initial setup. If you don’t have an internet connection at your location, you’ll want to choose a cellular system. Make sure that there’s sufficient signal strength at your site, and check the signal quality in the area before purchasing a cellular device.

2. How do we determine what kind of monitoring system and sensors we need?

A reputable manufacturer will have a well-trained support team that can assess your needs even without a site visit to determine which products are best for your application. If you feel you need them to check out your greenhouse operation,many companies can set up a video conference or FaceTime chat to substitute for being on site.

You will want to provide details about the scope and purpose of your cannabis growing operation. Important factors to discuss include:

  • Skeletal structure of the greenhouse (metal, plastic, wood, etc.) and the covering material (glass or plastic).
  • Floor space square footage and height of each of your greenhouses.
  • Number of greenhouse structures in your operation.
  • Outdoor climate to determine if you rely more on heating or air conditioning and the level of humidity control needed.
  • Space dedicated to phases of growth (cloning and propagation, vegetative, flowering) and the microclimates needed for each.
  • Types of lighting, ventilation and irrigation systems.
  • Level of technological automation versus manual operation in place.

The monitoring system representative will then determine the type of system that would best serve your operation, the number of base units you will need and the types of sensors required.

Image 2: Temperature display provides quick view of sensor data
Temperature display provides quick view of sensor data

The representative should also be able to provide tips on the placement of the sensors you’re purchasing. For example, to ensure thorough air temperature coverage, place sensors throughout the greenhouse, next to the thermostat controlling the room temperature and in the center of the greenhouse out of direct sunlight.

Note that there shouldn’t be a cost for a demo, consultation or assistance throughout the sales process. Be sure to ask if there are any fees or licenses to keep using the monitoring equipment after you purchase it.

3. Are sensors included with the monitoring system?

In most cases, sensors are sold separately. The sensors you select depend upon the conditions you want to monitor and how many you can connect to your base unit. Certainly, temperature is critical, but there are many other factors to deal with as well, such as humidity, CO2, soil moisture, water pH, power and equipment failure, ventilation and physical security.

For example, humidity has a direct impact on the photosynthesis and transpiration of plants. High humidity can also cause disease and promote the growth of harmful mold, algae and mildew. Sensors can detect changes in humidity levels.

Image 3: Water pH sensor
Water pH sensor

Like any other plant, cannabis needs CO2 to thrive, so it’s a good idea to include a CO2 sensor that will signal to the monitoring device when readings go out of the preset range. There are even sensors that you can place in the soil to measure moisture content to help prevent over- or underwatering, budget water usage costs, promote growth and increase crop yield and quality.

Of course, all the critical systems in your growing facility—from water pumps to irrigation lines to louvers—rely on electrical power. A power outage monitoring sensor detects power failure. It can also monitor equipment for conditions that predict if a problem is looming, such as power fluctuations that occur at specific times.

Ventilation systems not only help control temperature, they also provide fresh air that is critical to plant health. Automated systems include features like vented roofs, side vents and forced fans. Sensors placed on all these systems will send personnel an alert if they stop running or operate outside of preset parameters.

To monitor the physical security of your greenhouses, you can add sensors to entrance doors, windows, supply rooms and equipment sheds. During off hours, when no staff is on duty, you can remain vigilant and be alerted to any unauthorized entry into your facility.

4. Do monitoring systems only work with the manufacturer’s sensors?

Not necessarily. For example, certain monitoring units can connect with most 4-20mA sensors and transmitters regardless of the brand. When selecting sensors, you might have a choice between ones that are designed by the manufacturer to work specifically with the monitoring system or universal components made by a third party. If the components aren’t made by the system manufacturer, you’ll want to find out if they have been tested with the monitor you are choosing and if you need to work with another vendor to purchase the parts.

A humidity sensor mounted in a weatherproof enclosure
A humidity sensor mounted in a weatherproof enclosure

5. Is a monitoring system easy to set up, or do we need to hire an electrician?

Many monitoring systems are quick and easy to install, and users can often set them up without hiring an outside expert. Look for one that requires only a few simple physical installation steps. For example:

  1. Mount the device to the wall or somewhere secure;
  2. Plug it into an electrical outlet and an internet connection;
  3. Connect the sensors.

You connect the sensors to the base unit’s terminal strip using wire, which is included with many sensors. The range of many wired sensors can be extended up to 2,000 feet away from the base unit by adding wire that can be easily purchased at any home store. It’s a good idea to hire an electrician if you need to run wires through walls or ceilings.

Usually, once you plug in the device and connect the sensors, you then create an account on the manufacturer’s designated website and begin using your device. There should be no fee to create an account and use the site.

If the manufacturer doesn’t offer installation services, ask if they can recommend a local representative in your area who can set up your system. If not, make sure they provide free technical support via phone or email to walk you through the installation and answer any questions you might have about programming and daily usage.

6. Is there a monthly fee to access all the functionality of a monitoring device?

Many web- or cloud-based systems provide free functionality with some limitations. You might have to purchase a premium subscription to unlock features such as text messaging, phone call alerts and unlimited data logging access.

 7. Should we get a system that is wired or wireless? Will we need to have a phone line, cable, internet or something else?

Wireless can mean two different things as it relates to monitoring: how the system communicates its data to the outside world and how the sensors communicate with the system.

The most popular systems require an internet or WiFi connection, but if that’s not an option, cellular- and phone-based systems are available.

A hardwired monitoring system connects the sensors to the base device with wires. A wireless system uses built-in radio transmitters to communicate with the base unit. Some monitoring systems can accommodate a combination of hardwired and wireless sensors.

8. Can one system monitor several sensor inputs around the clock?

Once the monitoring system is installed and programmed, it will constantly read the information from the sensors 24/7. Cloud-based systems have data logging capabilities and store limitless amounts of information that you can view from any internet-connected device via a website or app.

If the system detects any sensor readings outside of the preset range, it will send an alarm to all designated personnel. The number of sensors a base unit can monitor varies. Make sure to evaluate your needs and to select one that can accommodate your present situation and future growth.

When a monitoring system identifies a change in status, it immediately sends alerts to people on your contact list. If you don’t want all your personnel to receive notifications at the same time, some devices can be programmed to send alerts in a tiered fashion or on a schedule. Multiple communications methods like phone, email and text provide extra assurance that you’ll get the alert. It’s a good idea to check the number of people the system can reach and if the system automatically cycles through the contact list until someone responds. Some systems allow for flexible scheduling, so that off-duty personnel don’t receive alerts.

9. Do monitoring systems have a back-up power system that will ensure the alarming function still works if the power goes out or if someone disconnects the power?

The safest choice is a cloud-based system that comes with a built-in battery backup that will last for hours in the event of a power failure. Cloud-based units constantly communicate a signal to the cloud to validate its online status. If the communication link is interrupted—for example by a power outage or an employee accidently switching off the unit—the system generates an alarm indicating that the internet connection is lost or that there is a cellular communications problem. Users are alerted about the disruption through phone, text or email. All data collected during this time will be stored in the device and will be uploaded to the cloud when the internet connection is restored.

If you opt for a cloud-based monitoring system, make sure the infrastructure used to create the cloud platform is monitored 24/7 by the manufacturer’s team. Ask if they have multiple backups across the country to ensure the system is never down.

10. What should we expect if we need technical support or repairs to the system?

Purchase your system from a reputable manufacturer that provides a warranty and offers full repair services in the event the product stops working as it should. Also, research to make sure their tech support team is knowledgeable and willing to walk you through any questions you have about your monitoring system. Often, support specialists can diagnose and correct unit setup and programming issues over the phone.

It helps to record your observations regarding the problem, so the tech team can look for trends and circumstances concerning the issue and better diagnose the problem. Ideally, the manufacturer can provide loaner units if your problem requires mailing the device to their facility for repair.

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

By Parastoo Yaghmaee, PhD
3 Comments

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

Applications for Tissue Culture in Cannabis Growing: Part 1

By Aaron G. Biros
5 Comments

Dr. Hope Jones, chief scientific officer of C4 Laboratories, believes there are a number of opportunities for cannabis growers to scale their cultivation up with micropropagation. In her presentation at the CannaGrow conference recently, Dr. Jones discussed the applications and advantages of tissue culture techniques in cannabis growing.

Dr. Hope Jones, chief scientific officer at C4 Labs

Dr. Jones’ work in large-scale plant production led her to the University of Arizona Controlled Environment Agriculture Center (CEAC) where she worked to propagate a particularly difficult plant to grow- a native orchid species- using tissue culture techniques. With that experience in tissue culture, hydroponics and controlled environments, she took a position at the Kennedy Space Center working for NASA where she developed technologies and protocols to grow crops for space missions. “I started with strawberry TC [tissue culture], because of the shelf life & weight compared with potted plants, plus you can’t really ‘water’ plants in space- at least not in the traditional way,” says Dr. Jones. “Strawberries pack a lot of antioxidants. Foods high in antioxidants, I argued, could boost internal protection of astronauts from high levels of cosmic radiation that they are exposed to in space.” That research led to a focus on cancer biology and a Ph.D. in molecular & cellular biology and plant sciences, culminating in her introduction to the cannabis industry and now with C4 Labs in Arizona.

Working with tissue culture since 2003, Dr. Jones is familiar with this technology that is fairly new to cannabis, but has been around for decades now and is widely used in the horticulture industry today. For example, Phytelligence is an agricultural biotechnology company using genetic analysis and tissue culture to help food crop growers increase speed to harvest, screen for diseases, store genetic material and secure intellectual property. “Big horticulture does this very well,” says Dr. Jones. “There are many companies generating millions of clones per year.” The Department of Plant Sciences Pomology Program at the Davis campus of the University of California uses tissue culture with the Foundation Plant Services (FPS) to eliminate viruses and pathogens, while breeding unique cultivars of strawberries.

A large tissue culture facility run in the Sacramento area that produces millions of nut and fruit trees clones a year.

First, let’s define some terms. Tissue culture is a propagation tool where the cultivator would grow tissue or cells outside of the plant itself, commonly referred to as micropropagation. “Micropropagation produces new plants via the cloning of plant tissue samples on a very small scale, and I mean very small,” says Dr. Jones. “While the tissue used in micropropagation is small, the scale of production can be huge.” Micropropagation allows a cultivator to grow a clone from just a leaf, bud, root segment or even just a few cells collected from a mother plant, according to Dr. Jones.

The science behind growing plants from just a few cells relies on a characteristic of plant cells called totipotency. “Totipotency refers to a cell’s ability to divide and differentiate, eventually regenerating a whole new organism,” says Dr. Jones. “Plant cells are unique in that fully differentiated, specialized cells can be induced to dedifferentiate, reverting back to a ‘stem cell’-like state, capable of developing into any cell type.”

Cannabis growers already utilize the properties of totipotency in cloning, according to Dr. Jones. “When cloning from a mother plant, stem cuttings are taken from the mother, dipped into rooting hormone and two to five days later healthy roots show up,” says Dr. Jones. “That stem tissue dedifferentiates and specializes into new root cells. In this case, we humans helped the process of totipotency and dedifferentiation along using a rooting hormone to ‘steer’ the type of growth needed.” Dr. Jones is helping cannabis growers use tissue culture as a new way to generate clones, instead of or in addition to using mother plants.

With cannabis micropropagation, the same principles still apply, just on a much smaller scale and with greater precision. “In this case, very small tissue samples (called explants) are sterilized and placed into specialized media vessels containing food, nutrients, and hormones,” says Dr. Jones. “Just like with cuttings, the hormones in the TC media induce specific types of growth over time, helping to steer explant growth to form all the organs necessary to regenerate a whole new plant.”

Having existed for decades, but still so new to cannabis, tissue culture is an effective propagation tool for advanced breeders or growers looking to scale up. In the next part of this series, we will discuss some of issues with mother plants and advantages of tissue culture to consider. In Part 2 we will delve into topics like sterility, genetic reboot, viral infection and pathogen protection.

Understanding Dissolved Oxygen in Cannabis Cultivation

By Aaron G. Biros
4 Comments

Oxygen plays an integral role in plant photosynthesis, respiration and transpiration. Photosynthesis requires water from the roots making its way up the plant via capillary action, which is where oxygen’s job comes in. For both water and nutrient uptake, oxygen levels at the root tips and hairs is a controlling input. A plant converts sugar from photosynthesis to ATP in the respiration process, where oxygen is delivered from the root system to the leaf and plays a direct role in the process.

Charlie Hayes has a degree in biochemistry and spent the past 17 years researching and designing water treatment processes to improve plant health. Hayes is a biochemist and owner of Advanced Treatment Technologies, a water treatment solutions provider. In a presentation at the CannaGrow conference, Hayes discussed the various benefits of dissolved oxygen throughout the cultivation process. We sat down with Hayes to learn about the science behind improving cannabis plant production via dissolved oxygen.

In transpiration, water evaporates from a plant’s leaves via the stomata and creates a ‘transpirational pull,’ drawing water, oxygen and nutrients from the soil or other growing medium. That process helps cool the plant down, changes osmotic pressure in cells and enables a flow of water and nutrients up from the root system, according to Hayes.

Charlie Hayes, biochemist and owner of Advanced Treatment Technologies

Roots in an oxygen-rich environment can absorb nutrients more effectively. “The metabolic energy required for nutrient uptake come from root respiration using oxygen,” says Hayes. “Using high levels of oxygen can ensure more root mass, more fine root hairs and healthy root tips.” A majority of water in the plant is taken up by the fine root hairs and requires a lot of energy, and thus oxygen, to produce new cells.

So what happens if you don’t have enough oxygen in your root system? Hayes says that can reduce water and nutrient uptake, reduce root and overall plant growth, induce wilting (even outside of heat stress) in heat stress and reduce the overall photosynthesis and glucose transfer capabilities of the plant. Lower levels of dissolved oxygen also significantly reduce transpiration in the plant. Another effect that oxygen-deprived root systems can have is the production of ethylene, which can cause cells to collapse and make them more susceptible to disease. He says if you are having issues with unhealthy root systems, increasing the oxygen levels around the root system can improve root health. “Oxygen starved root tips can lead to a calcium shortage in the shoot,” says Hayes. “That calcium shortage is a common issue with a lack of oxygen, but in an oxygen-deprived environment, anaerobic organisms can attack the root system, which could present bigger problems.”

So how much dissolved oxygen do you need in the root system and how do you achieve that desired level? Hayes says the first step is getting a dissolved oxygen meter and probe to measure your baseline. The typical dissolved oxygen probe can detect from 20 up to 50 ppm and up to 500% saturation. That is a critical first step and tool in understanding dissolved oxygen in the root system. Another important tool to have is an oxidation-reduction potential meter (ORP meter), which indicates the level of residual oxidizer left in the water.

Their treatment system includes check valves that are OSHA and fire code-compliant.

Citing research and experience from his previous work, he says that health and production improvements in cannabis plateau at the 40-45 parts-per-million (ppm) of dissolved oxygen in the root zone. But to achieve those levels, growers need to start with an even higher level of dissolved oxygen in a treatment system to deliver that 40-45 ppm to the roots. “Let’s say for example with 3 ppm of oxygen in the root tissue and 6ppm of oxygen in the surrounding soil or growing medium, higher concentrations outside of the tissue would help drive absorption for the root system membrane,” says Hayes.

Reaching that 40-45 ppm range can be difficult however and there are a couple methods of delivering dissolved oxygen. The most typical method is aeration of water using bubbling or injecting air into the water. This method has some unexpected ramifications though. Oxygen is only one of many gasses in air and those other gasses can be much more soluble in water. Paying attention to Henry’s Law is important here. Henry’s Law essentially means that the solubility of gasses is controlled by temperature, pressure and concentration. For example, Hayes says carbon dioxide is up to twenty times more soluble than oxygen. That means the longer you aerate water, the higher concentration of carbon dioxide and lower concentration of oxygen over time.

Another popular method of oxidizing water is chemically. Some growers might use hydrogen peroxide to add dissolved oxygen to a water-based solution, but that can create a certain level of phytotoxicity that could be bad for root health.

Using ozone, Hayes says, is by far the most effective method of getting dissolved oxygen in water, (because it is 12 ½ times more soluble than oxygen). But just using an ozone generator will not effectively deliver dissolved oxygen at the target levels to the root system. In order to use ozone properly, you need a treatment system that can handle a high enough concentration of ozone, mix it properly and hold it in the solution, says Hayes. “Ozone is an inherently unstable molecule, with a half-life of 15 minutes and even down to 3-5 minutes, which is when it converts to dissolved oxygen,” says Hayes. Using a patented control vessel, Hayes can use a counter-current, counter-rotational liquid vortex to mix the solution under pressure after leaving a vacuum. Their system can produce two necessary tools for growers: highly ozonized water, which can be sent through the irrigation system to effectively destroy microorganisms and resident biofilms, and water with high levels of dissolved oxygen for use in the root system.

Preventing Yeast and Mold with Two-Way Humidity Control

By Aaron G. Biros
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When a grower harvests their cannabis plants, they process it by drying, curing and trimming the plant material. Dried cannabis ready for the consumer can often sit on retail shelves for months before it is purchased. According to the Cannabis Safety Institute, trimming is the processing stage with the highest level of human handling, and thus presents the most significant opportunities for microbiological contamination.

The Cannabis Safety Institute recommends workers handling dry cannabis wash their hands periodically, generally conform to food safety rules and wear gloves at all times. In addition to these tips, looking at relative humidity is a good tool to mitigate contamination concerns like the growth of yeast and mold spores. Mold spores can grow quickly when there is enough moisture, but if the cannabis is dry enough, mold spores cannot develop.

Growers controlling the relative humidity of their finished product in the past often placed an orange peel or a wet cotton ball in a jar with dried cannabis to retain the weight from water and keep it from over-drying. Those tactics have since been improved upon using modern technology.

Water activity is a measure of the relative humidity immediately adjacent to the product, according to Bob Esse, vice president of research at Boveda. “Cannabis’ relative humidity will reach equilibrium with the surrounding environment over time, which is why it is so critical to manage this adjacent atmosphere,” says Esse. “Moisture content is the total water present in the product and is a variable that changes in its relationship to water activity from one strain or type of product to the next.”

Back in 1997, Boveda first patented two-way humidity control. For the last 20 years, that company has made humidity control products for packaging in a variety of industries, like wooden musical instruments, pharmaceuticals, medical devices, electronics, tobacco, photos and documents and perhaps most notably for keeping cigars at the right humidity level in a humidor. According to Charles Rutherford, business development director at Boveda, he saw people buying their products meant for cigars, but using them with cannabis. About six years ago, they started developing a product specifically for the cannabis market.

The science behind it is relatively simple, says Rutherford. “Certain salts saturated in water can naturally regulate humidity- we just developed a cannabis-specific humidity level and patented the packaging around it that purifies the water and can come in direct contact with cannabis,” says Rutherford. “Using water activity meters and a moisture isotherm test, we determined the most appropriate range of humidity levels that cannabis will remain stable.” That range turned out to be between 59% and 63% humidity level for the properties in dried cannabis to stay the same.

According to Rutherford, it is a little more complex than just a range to stay in. “There are different humidity levels that certain strains prefer, but there are personal preferences, regions and other factors to consider when determining the levels of humidity ideal for cannabis,” says Rutherford. “We wanted to understand what people consider to be perfect.” In their research they found that depending on the region of the country, that humidity level varies considerably. “Using a water activity meter we could tell exactly what people prefer,” says Rutherford. Colorado, for example, prefers significantly drier cannabis than the Pacific Northwest, according to their findings.

Right now, Boveda has two-way humidity controllers set at 62%, 58% and soon they will have an under 50% option (appealing to the Colorado market). Using a device to accurately control the humidity level in cannabis can help growers and retailers prevent contamination from the biggest source of concern: water. “There is a ton of talk about pesticide contamination, but the reality is even if the flower is grown organically, you can still encounter safety problems when the moisture level is off,” says Rutherford. From a medical perspective, keeping dried cannabis at an ideal humidity level helps stabilize the properties of it, maintaining the medical efficacy. “If this is something people use for a medicine, it should be at an ideal condition,” says Rutherford. “Quantifying and understanding what humidity level is right is what we are helping accomplish.” For patients with compromised immune systems that need safe, consumable cannabis, a humidity control device can help prevent contamination and ensure a certain degree of safety in their medicine.

On a retail level, the packaging insert can extend the shelf life of products and maintain the quality. “The world has known for decades that 70% humidity level for cigars is ideal,” says Rutherford. “The cannabis world hasn’t had a moisture standard or understanding of what is proper until very recently.” That 62% humidity level determined after commissioned testing is a good standard to reference when determining your own ideal humidity level.

Growers also recognize the value in keeping their cannabis at the right humidity level beyond the obvious safety concerns. “As cannabis dries out and loses its humidity, the overall weight is reduced,” says Rutherford. “Precision humidity control gives a uniform humidity throughout the flower, leaving out the mystery for growers and maintaining weight, meeting the nexus between quality and weight.” According to Rutherford, growers have an incentive to package their cannabis a little on the wet side. “Because it weighs the most when wet, it is sold by weight and it will lose moisture over time, the incentive to deliver product that will dry out over time- that can create a lot of problems by having high moisture content.” For the first time ever, people can dramatically extend the shelf life of dried cannabis, instead of letting products naturally deteriorate and go bad over time. “For the first time ever, it allows you to extend the shelf life of dried cannabis for aging cannabis like wine and cigars,” says Rutherford.

The data from that Cannabis Safety Institute report, collected by AquaLab and CannaSafe Analytics using a vapor sorption analyzer, shows a cutoff of 65% relative humidity. These findings give the industry a lot of guidance in working to reduce the amount of yeast and mold contamination, says Bob Esse. “If your dried cannabis is above 65% relative humidity and you are a retailer, you should send that product back to the grower because it wasn’t dried properly, is vulnerable to mold and yeast spores and thus not safe for the consumer,” says Esse.

Pointing to the report, Esse says foods with high moisture content are able to support robust microbial population growth, which can lead to bacterial and fungal infections. “Water activity is what impacts whether microorganisms can grow or not.” By using two-way humidity control technology, growers and retailers can mitigate risks of contamination, improve quality and extend the shelf life of their products.