Harmful Pathogens & Cannabis

How to avoid pathogens from destroying both your cannabis and your health.


If you’re familiar with the story about a man dying from a rare fungal infection due to smoking moldy cannabis, you might be having mixed emotions regarding the plant and its medicinal qualities. That’s why we’re going to give you a quick break-down of:

- what’s been found growing on cannabis
- how these pathogens can potentially harm us
- what to look for on your cannabis before smoking it
- and tips on how to avoid pathogens from destroying both your cannabis and your health

As you know, mold grows where there’s moisture, needing only a 15% humidity level to survive. While growing facilities do all that’s in their power to ensure their plants are fully dried before allowing dispensaries to sell them, faint traces of spores still make their way onto the plant material. For recreational users and patients that don’t have debilitated immune systems from their illness or chemotherapy, these faint traces are harmless. In fact, mold and fungi are everywhere in nature – without them, plant matter like leaves wouldn’t decay, and mushrooms – which are a fungus – wouldn’t be served in food.

However, for those of us that do have debilitated immune systems, ingesting molds or fungi can become life-threatening. While there’s been about 20 different pathogens found in trace amounts on cannabis collected from dispensaries across the state of California, three of them stand out you should be aware of.
The first is aspergillus. It usually grows on plants and trees, helping to decay vegetation, especially dead leaves. This applies to cannabis as well, and unfortunately there were two case studies in 2011 of medical cannabis consumers that developed chronic pulmonary aspergillosis, or CPA, after being exposed to aspergillus believed to be on the cannabis they were consuming.

The second is botrytis, more commonly known as gray mold. It’s the more common pathogen found on cannabis when the plant does in fact become exposed to conditions for molds. When inhaled, acute respiratory problems can unfold, or an allergic reaction.

The third is Cladosporium, usually found on porous materials such as wood. When ingested, symptoms similar to hay fever can arise and cause asthma attacks or lead to the development of pneumonia.

Keep in mind that fungi can survive harsh conditions, and the fire from smoking cannabis via a pipe or bong will not kill all of the spores. However, minute trace amounts of these molds and other pathogens are harmless for those of us with healthy immune systems.

The features of moldy cannabis can be hard to spot, considering the various shades of all the strains that now exist. While you can certainly eye mold growing on your cannabis, it’s better to observe it either under a magnifying glass or under a black light – the black light will reveal mold by giving it a distinct green tint. You can certainly smell the cannabis too for musky; urine-like stale scents, though the many terpenes found in cannabis may throw off your senses. If simply eyeing it, look for distinct white, black, gray, or dark green patches. Up close, it will look like a fine spider web covering the bud – which is not what normal trichomes do, so don’t mistake trichomes for mold.

If you’ve already smoked some of your cannabis and are worried it may have had mold on it, pay attention to symptoms such as wheezing, headache, reduced ability to smell, diarrhea, shortness of breath, fever, and runny nose. These symptoms will more than likely go away on their own so long as you discontinue smoking any more contaminated cannabis – just ensure they do not worsen and develop into a serious concern such as infections in the lungs or other organs.

Once your cannabis is in your hands and you’ve properly observed it, the best way to keep it pathogen-free is to store it in a dry, contained environment like a mason jar. If your cannabis has somehow obtained some moisture by accident, you can choose to place your cannabis in the oven at 300 degrees for about 20 minutes to dry it and kill most spores, however, this won’t ensure that the cannabis is entirely free of pathogens.

If you consume cannabis to help with symptoms of autoimmune disorders or for the side-effects of chemotherapy, it’s highly recommended to invest in a small black light to ensure your cannabis is safe. If you have a healthy immune system and purchase your cannabis from a dispensary, then chances are you’ll be just fine as cannabis now goes through rigorous processing to ensure its quality.