There are literally hundreds of different bacteria and fungi associated with cannabis grown indoors which has triggered almost universal adoption of quality assurance testing of cannabis for a select group of pathogenic bacteria that are highly infectious and fungi known to produce potent toxins.
The different microbial species that make up the cannabis microbiome is just now being delineated by groups such as Medicinal Genomics in Woburn, Massachusetts through the application of next generation sequencing surveys from cannabis sold in dispensaries. Luckily the vast majority of microorganisms associated with cannabis are not capable of causing any health problems to able-bodied humans. Most of the microbes are plant-associated with a handful being actual plant pathogens. There is however a subset of microorganisms, mainly fungi, associated with post-harvest and storage that can lead to serious problems for immuno-compromised patients by eliciting allergenic reactions when inhaled and/or they produce dangerous toxins having varying clinical consequences.
By far, the best approach for cultivators to embrace at the outset is to start their grow clean and keep it clean, thereby eliminating any opportunity for unwanted microbial contaminants into the facility. The clean approach requires complete diligence in adhering to strict standards of operations for both employees and any visitors through controlled access. Employees and visitors should be supplied with freshly laundered work uniforms and disposable gloves, all working surfaces should be wiped down several times a day with a 10% bleach or 70% ethanol solution. The presence of human pathogens can be eliminated through mandatory hand-washing, much like occurs in a doctor’s office. Install numerous hand-washing stations with soap and warm water, post signs reminding employees to wash their hands often and especially before entering a grow room.
Careful cultivation techniques should also aim to eliminate the introduction of any human or plant pathogens and insects, paying ever close attention at harvest time. Plant material below 15% moisture content cannot support opportunistic fungi. Water and nutrient sources should have in-line filtration units to remove microorganisms from reaching the plant, water reservoirs on humidifying devices should be religiously cleaned with a 10% household bleach solution and all air filters should be replaced on a monthly basis.
While the complete elimination of microbial populations is not possible in an open plant grow environment, taking a conscientious approach to protecting your next cash crop will be worth every small endeavor toward running a clean operation. Best of luck ahead!