Microbial Contaminant Remediation, Molds and Fungi

Discussion in 'Growing Marijuana Indoors' started by steephilllab, Jan 27, 2014.

  1. #1 steephilllab, Jan 27, 2014
    Last edited by a moderator: Jan 27, 2014
    See original article: Steep Hill Halent Laboratories
    \nINTRODUCTION – As the cannabis industry emerges, many questions surrounding the safety and efficacy of cannabis remain unanswered. In contrast with almost all other industries in the United States, where products are grown for human consumption and/or medical use, the cannabis industry has virtually no guidelines, limitations, or quality assurance mechanisms in place to protect its employees and consumers, aside from those provided by third parties such as Steep Hill Halent Laboratories. As a result, the quality of cannabis can vary widely from season to season, farm to farm, between growers, collective dispensaries, and even day to day within the same collective. An industry wide lack of standardized practices and remediation strategies virtually ensures that this will continue. This writeup aims to help providers begin a path towards effective quality assurance over the medicinal products they provide to patients, and become leaders in the industry in the process.
    \nWHAT ARE MOLDS – Molds are biological organisms in the Fungi kingdom. There are many thousands of species of mold in the world. Molds are everywhere. They are in the air we breathe, the food we eat, and the water we drink. Many molds are innocuous, yet many others are potential human pathogens. All molds require moisture to live and reproduce, but mold spores can survive exceptionally extreme conditions devoid of water or warmth.
    \nMOLDS AND CANNABIS – Certain molds seem to continually reappear in the medical cannabis supply. Many of them are fairly ubiquitous and most likely would appear on many similar large leafy green plants. Plants themselves make exceptionally good ecosystems, and generally support a large biological array of species. They are excellent sources of water and sugar, which many animals, bacteria, and molds require for survival. Cannabis is no different, and just about any plant, whether it is grown indoors or outdoors is usually teeming with life.
    \nUnder average conditions, you are more likely to find mold spores on a plant that is outdoors. Most molds live outside where there is ample access to water and food. But molds that are outdoors are also more likely to be kept under control by natural checks and balances. Indoors, if molds are able to gain a foothold natural checks are generally lacking, and a small problem can quickly grow to be an epidemic. In grow rooms, the problem is usually exacerbated by high levels of heat and moisture. Once mold is able to gain a foothold inside, it can be extremely difficult to regain control of the situation.
    \nThe following is a list of typical molds found on mold in California in order of increasing rarity:
    • Powdery Mildew
    • Penicillium
    • Yeast
    • Aspergillus
    • Cladosporium
    • Fusarium
    • Botrytis
    • Aureobasidium
    • Acremonium
    and more…..
    \nThe relative frequency of these molds will change based on specific geographical locations and environmental conditions.
    \nMOLD PREVENTION – The main key to preventing mold is controlling moisture. For outdoor growers, this can be very difficult. In the late fall, the likelihood of rain increases with each passing day. Once it rains, the soil often becomes saturated and water remains condensed on the underside of leaves and in the tight space between flowering tips. One of the worst things that can happen to an outdoor grower is for a period of rain to be followed by a warm windless sunny day. If this happens, the area underneath the canopy and nearest to the soil can become like a sauna, and a mold explosion can ensue.
    \nThere are techniques that can be used to limit the risks associated with a rain event. Completely removing all vegetative material on the underside of the plant within the first 2-3 feet nearest the soil significantly increases airflow under the plants. Air flow will evaporate moisture faster reducing the period of time most amenable to mold growth.
    \n Indoor growers will find that they are better able to control the moisture of their grows. They should expect to invest a decent amount of money into a quality dehumidification system. Relative humidity should be kept at or below 55%. While less important indoors, reducing vegetative material in the few inches nearest to the growing medium can be helpful.
    \n Most molds prefer environments that are on the slightly acidic side. It can therefore be helpful to perpetuate conditions are alkaline. Alkaline water itself can go a long way toward reducing the risk of a powdery mildew mold (PMM) infection. Neem oil can be helpful in eliminating PMM, but is also useful as a preventative measure. Some advanced growers, especially in greenhouses where the risk of mold infection is high, have begun using foggers and nebulizers with anti-fungal compounds. In greenhouses, where the risk is highest these devices maybe used as much as 16 hours a day. This can almost guarantee the elimination of the risk of mold infection.
    \n Animals should be kept out of indoor grows and cure spaces. Dogs and cats will shed dander, and can bring any number of unwanted mold and bacteria into your workspaces. In all grows, plants that are weak or sick should be destroyed and removed from the garden. Weak and sickly plants generally have weakened defenses and can be a target for any number of diseases and pathogens.
    \nMOLD REMEDIATION (INDOOR GROWS/CURE SPACES) – The first step in remediating mold problem is to determine its cause. In order to do so, you must think like a mold. Molds thrive in environments rich in moisture, food, and warmth.
    \nThe main factor is moisture. Controlling moisture indoors will go a long way toward controlling a mold problem. In grow rooms, water must be present in order to keep the plants alive. The relatively high temperatures needed for optimal plant growth are unfortunately generally in the optimal range for mold proliferation. Higher temperatures also increase the air's ability to hold moisture, which means that moisture will steadily be moving from the soil to the air via evaporation, and also by means of transpiration through plant pores. This means that a grow room will by default become humid if no process is in place to remove humidity. If a mold problem exists, the first thing that should be done is to implement a dehumidification system to bring relative humidity below what is optimal for mold growth.
    \nMolds reproduce by making spores that usually cannot be seen without magnification. Mold spores waft through the indoor and outdoor air continually. When mold spores land on a damp spot indoors, they may begin growing and digesting whatever they are growing on in order to survive. In grow rooms, the likely source of food will be dead plant matter and organic matter from the soil. If there is an excessive build up of food, it will be easier for mold to grow. Growers should completely clean grow rooms of plant debris regularly.
    \nIn cure spaces, dead and drying leaves will accumulate on the floor. It is absolutely imperative that a cure space be meticulously cleaned at least once a week. Do not allow leaves to accumulate on the floor. They will dry out and become crunchy and then turn to dust. Once they become dust they can become suspended in the air and contribute greatly to a potential mold outbreak. It is advisable to clean the floor at least once a week with a light bleach solution (i.e. 2 TBSP per gallon of water), or other anti fungal liquid mixture. Once a month the walls and ceiling should be also be scrubbed. If the cure space has mold contamination, extreme steps may be necessary to eliminate it. If you establish your cure space as a source of mold contamination, do the following:
    1. \tEmpty cure space of all items, racks, trays, and cannabis. Only bare walls and floors should be exposed.
    2. \tClean all surfaces (i.e. floor, ceiling, and walls).
    3. \tIf the contamination is slight, bleach may work to kill it. Bleach is not an EPA approved biocide. Products such as Mold Stat, or Du Pont Rely +ON. These are very strong chemicals, but may be the only way to eliminate serious contamination.
    4. \tSpray surfaces with encapsilant. This may not be necessary if the problem is not serious.
    5. \tClean and disinfect all racks, dehumidifiers, air conditioners, etc. before returning them to the space.
    6. \t<span style="font-family:'times new roman', times, serif;">Consider changing air filters on air conditioners and dehumidifiers if they are removable.</span>
    Dehumidification is necessary for proper curing of cannabis. Sometimes it can be difficult to keep humidity low in a cure space. Wet cannabis is around 80% moisture content. In order for the cannabis to properly dry, that moisture must be removed from the plant material in a timely manner. The need to remove moisture from the plant is balanced by the need to allow chlorophyll to escape the plant. If the plant dries too quickly, chlorophyll will become trapped in the plant and it will smell like hay and potentially be a harsher smoke. If mold has become a problem in a cure space and the space cannot be cleared immediately, a grower may find that lowering the temperature will help stop the problem from spreading. This will lower the relative humidity in the cure space, and inhibit more mold growth. It is highly unadvisable to continue using a cure space once mold has gained a foothold.
    \n Cure spaces should not have any wood surfaces. Ideally the walls, floor, and ceiling should be made of metal, glass, or synthetic materials like plastic. You will find that these materials naturally inhibit mold growth. If a surface is made of wood, and mold has begun growing on it, the only solution may be to sand the surface down until the mold is no longer visible, and then apply a sealant. Mold eats wood. Avoid having it in your cure space.
    \n Ventilation can also be a source of mold contamination. Cure spaces and grow rooms should not pull unfiltered air in from the outdoors. Ideally, both should have HEPA filters on any intakes, and the rooms should be positively pressurized. This means that the air pressure inside the room is greater than the areas around. Air will flow from within the room to the outside through unsealed cracks and leaks.
    \nPACKAGING AND HANDLING – Medical cannabis should be handled on clean surfaces. Vending and weighing surfaces in dispensaries should be made of glass, stainless steel, or some other surface that is non- porous, and can be easily cleaned and sterilized when necessary. Scale surfaces should be cleaned between batches. Use methanol, or some other non-toxic cleaning agent to wipe surfaces. Ideally sterile wipes should be used to assure the highest levels of cleanliness.
    \nEvery person who handles medical cannabis after it is cut down should wear gloves.
    \nUse clean fresh packaging. Standards such as oven bags are acceptable. Do not re-use these bags. Sealable vacuum bags also work well. Sterile bags are available and should become the standard over time. Steep Hill Halent Laboratories also offers tamper-proof, nitrogen flushed packaging as a service to ensure the freshness and longevity of our clients' products.
    \n Medical grade cannabis should never be placed on the ground. Do not package it in unclean areas. It should not be handled in rooms with carpet. The shaggier the carpet, the higher risk it will retain contaminates and other risk elements. Carpeted handling areas are undesirable in general. Collectives should only handle medicine on counters that are above waste level.
    \nMicrobiological screening, penicillium plated in agar | Copyright Steep Hill Labs Inc. 


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