Does vaporization reduce the microbial load of cannabis?

The main difference between medical cannabis and recreational cannabis is the need to ensure the lowest possible microbial load for therapeutic use. Some patients have weakened immune systems and cannot afford to take a medication that might contain mold or harmful microbes.

The most common method is the’spray administration : Dried cannabis flowers are heated in a vaporizer. The resulting vapor is then inhaled to enjoy only the active compounds, without the harmful byproducts associated with combustion.

Exposure to high temperatures—typically between 190 and 220°C in a vaporizer—is known to kill microorganisms, including bacteria and fungi. However, microbial death depends on the duration and temperature of exposure. Hence the need to know whether a Commercial vaporizer, Volcano-style When used in a clinical setting, it significantly reduces the microbial load in cannabis.

What is the impact of vaporization on the microbiological quality of cannabis?

To answer this question, a team of researchers from the Food and Drug Administration (FDA), the U.S. Food and Drug Administration, was supplied with cannabis by the National Institute on Drug Abuse (NIDA).

Three types of cannabis were used in the study: a placebo with no detectable THC, cannabis with a low THC content (1.90 %), and cannabis with a «high» THC content (6.50 %).

They were then exposed either to no heat or to heating for 30 or 70 seconds at 190°C.

A phosphate-buffered saline solution was added to the samples, which were then shaken to resuspend the microorganisms. Microbial growth following heat inactivation or vaporization was assessed by inoculating the samples onto growth media and determining the total number of aerobic microorganisms and the total number of yeasts and molds.

The authors of the study finally concluded that:

• The standard 70-second vaporization at 190°C did not result in a significant reduction in the existing microbial load
• A vaporizer cannot be considered effective in reducing the microbial risks associated with inhaling cannabis
• Other decontamination methods, such as gamma radiation, germicidal ultraviolet irradiation or pasteurization may therefore be necessary to limit microbial contamination of cannabis