Cold Plasma Disinfection: The Future of Medical Cannabis?

The last decade has shown an explosive growth in the demand and use of cannabis in general and medical cannabis in particular. With the increase in cannabis consumption, so is the awareness to some of the risks involved, one of which is infection caused by the inhalation of cannabis contaminated with bacteria, yeast, and mold. This risk becomes especially critical for patients with a weakened immune system.

There are two disinfection methods in the market today, Gamma irradiation sterilization and Beta radiation. Both options are expensive, require complex logistics, have a considerable effect on cannabis terpenes, and change in the look and feel of the cannabis, which is viewed very negatively by the users. Cold Plasma disinfection, a technology commonly used for disinfection in multiple medical and non-medical applications, offers a solution to the drawbacks mentioned above and may be a preferred alternative to the existing solutions.

What is medical cannabis?

Medical cannabis is cannabis that is prescribed by physicians for their patients. The use of medical cannabis has increased considerably in recent years in North America, Europe and Australia, but the possession of the product is still illegal under federal law in many countries. Medical cannabis is used for multiple medical uses, among them reduction of nausea and vomiting during chemotherapy, improvement of appetite in people with HIV/AIDS, and reduction of chronic pain. Medical cannabis is also used sometimes as a general analgesic and for antibacterial and anti-inflammatory treatment.

Medical cannabis – why growing methods matter

Recent years have also shown dramatic improvement in the growing conditions of cannabis. However, growing plants under sterile conditions is not expected to be achievable in the foreseeable future, and like most other plants, cannabis is infected with pathogens such as molds, yeast, bacteria and fungal spores. Unlike other edible plants that end up in the digestive system, cannabis is inhaled and reaches the lungs. This may cause mild symptoms such as chest pains, weakness and headaches, or may even lead to serious conditions such as lung or blood infection, and there are some reported cases of death in patients with a weakened immune system (such as patients with HIV/AIDS or after going through chemotherapy).

Disinfection methods of medical cannabis

Due to these risks, most countries require disinfection of medical cannabis against molds, yeast, bacteria and fungal spores. The two most common methods are Gamma and Beta radiation.

Gama Irradiation

Gamma irradiation sterilization in cannabis involves exposing the product to high energy gamma rays which in turn damages DNA strands present in microbes. This in turn stops the multiplication of microbes which leads to their death. Irradiation has a considerable effect on cannabis terpenes which in turn causes a change in the taste and smell of cannabis during smoking or vaporizing. Gamma irradiation disinfection is the most complicated method for treating microbial cannabis since it requires shipping the cannabis to a special location for irradiation. In addition, a Gamma facility is very expensive, and it’s not considered environmentally friendly.

Electron Beam (Beta)

Electron Beam is produced by an electron accelerator that does not use any radioactive material. Beta radiation sterilization is done using an ionizing beam. Ionizing radiation results in the formation of free radicals which interrupt the chemical and metabolic process of molds and bacteria causing them to die. Ionizing beta radiation does not expose cannabis to too high heat or ultraviolet rays, and it does not leave dangerous residue at the end of the process, unlike fungicides. However, the cost of Beta machines is very high and as a result they are normally based in a central location and all cannabis needs to be shipped there for treatment.

Cold Plasma Disinfection

Plasma is commonly referred to as the fourth state of matter. Cold plasma is produced through operating a high voltage electrical charge leading to the creation of a mix of electrons, ions, photons and free radicals which in turn initiate oxidative reactions at the surface of live bacteria and spores. Plasma destroys the cell walls of fungal spores by creating holes in membranes of bacteria and spores causing their death.

Plasma also neutralizes a wide range of bacteria and reduces the concentration of colony-forming units in molds. Plasma not only kills molds but also reduces the levels of mycotoxins already released by the mold.

Why cold plasma disinfection is best for medical cannabis

Cold plasma treats only the surface of cannabis flowers and hence does not affect the concentration of cannabinoids and terpene molecules are unaffected.

Cold plasma as a disinfection method has proven to reduce colony-forming units of different types of molds without affecting the concentration of cannabinoids and terpenes. It does not require passing through heat or thorough radiation to kill micro-organisms making it a natural method of disinfection.

Plasma is much more affordable than Gamma irradiation or Beta radiation, and more importantly, it can be done on site, before final packaging or shipping to further processing at a GMP cannabis facility.When compared to other methods of medical cannabis disinfection, the cold plasma method has proven to be effective, inexpensive and relatively easy to implement.

About the author

Chen Porat is the Co-founder and CEO of Nova Plasma, a privately-held Israeli company, developing and marketing an innovative cold plasma platform technology. Nova Plasma’s technology can be applied to numerous medical and agrotech applications, such as surface activation, disinfection and tissue regeneration.