The Disgusting Truth About Microbial Contamination in Cannabis

Yet another reason to grow your own.

May 24, 2023

If you live in a legal market like I do in Colorado, you've likely seen "recalls" in the industry, either on social media stories from those working in it, or covered by your local and regional publications.

Recently, a webinar with Dr. Tess Eidem focused on the microbial risks of cannabis came across my radar, and it has been sitting in an open tab in my browser ever since. Until this morning, when I was able to sit down and put some time aside to let my jaw hit the floor.

And then, as I sat down to finish this piece, yet another recall hit the wire for Colorado, again for "potentially dangerous levels of mold aspergillus" (also the leading cause of fungal respiratory infections among cannabis users, but I'm getting ahead of myself).

If you only have a few seconds to skim this issue, here's the meat of it:

Microbial risk in cannabis is very real (and cannabis users as a whole are 3.5x more likely to have a respiratory fungal infection than non users).
That risk can be anywhere from mild irritation to COPD- and lung cancer-causing or anaphylactic shock-inducing.
That risk is not mitigated by "fire" or "heat" as many suggest smoking and vaporization address.
Current state-legal remediation processes for recovering adulterated products are not approved in other parallel industries (tobacco, medicinal herbs, cooking herbs, etc.)
Global Ag and Health agencies strongly and openly oppose the use of remediation as it is being used in state-legal cannabis.

Micro Risks In Cannabis with Dr. Tess Eidam

If you'd like to watch the entire talk yourself, the video is linked above, but I've done my best to save you 30 minutes and compile the most important aspects below:

3 Common Microbial Myths—BUSTED
9 Shocking Takeaways: Stats & Quotes
5 Unanswered Questions
3 Real-World Implications

3 Microbial Myths Most Cannabis Consumers Believe—BUSTED:

Myth #1. Smoking and vaporizing reduces potential contamination risks.

Busted: Living and Non-Living microbial contamination is not reduced by combustion or vaporization (and the collectable bioburden is very much detectable in consumers' lungs). That means heat from your lighter or vaporizer isn't enough to clean up any dirty weed that made its way through testing to your stash.

Myth #2. Microbial Reduction methods used in cannabis are standard in other, parallel industries like medicinal and edible herbs

Busted: Microbial reduction in cannabis is often remediation to recover adulterated material, rather than prevention efforts to avoid contamination. This is the opposite of what is done in tobacco and other crops, and is prohibited in parallel industries. It is a natural phenomena to assume those in any legal industry are doing their best, but, as we all know is common in any workplace, many are just doing what's allowed.

Myth #3. State regulatory bodies allow microbial reduction because it is an accepted tool endorsed by global health agencies

Busted: Global health agencies have condemned the practice in cannabis and demand that products treated with such methods be clearly labeled (both of which are largely ignored by licensed operators forced to decide between state-allowed remediation or losing their business from a failed crop). The unfortunate truth is that, with all of the excess costs of working in this space, many decisions are made based on the bottom line.

9 Shocking Takeaways from Dr. Eidem's Micro Risks to Cannabis:

"Microbes survive smoking and vaporization."

Covered above, but holy shit did my jaw hit the floor. In the same way we used to say "Well, the beer in the beer pong cups kills the germs on the ball," the idea that lighting something on fire would clean it feels logical, but is not. Microbes survive your vaporizer like cockroaches survive a nuke.
Cannabis users are 3.5x more likely to have respiratory fungal infections.

Fascinating, but also makes sense when you think about aspects like "smoker's cough" that even non-tobacco-consuming cannabis consumers are affected by. Something I'll get into below un unanswered questions, but this brings to light whether we may have misidentified and misdiagnosed adverse reactions to cannabis without considering microbial contamination.
"Microbes don't have to be alive to be harmful":

Non-living biological agents, byproducts, and allergens are present and can lead to respiratory issues including asthma, emphysema, bronchitis, COPD and lung cancer.
And, a step further, even small fragments—like broken up cell walls—can make their way through combustion and vaporization into the smoke and into your lungs, and can still cause an issue. Yuck.
The presence of microbial and fungal allergens can cause severe reactions when smoked or vaporized, including anaphylactic shock.

Dr. Eidem likened this to a peanut allergy in the talk. Not something you'd want to experience after breaking down some bud or hitting the joint being passed around.
No microbial reduction methods currently being used in cannabis have been validated according to universal standards (will not reach 5 Log—99.999% reduction—status).

There is a globally accepted standard for microbial reduction processes that is explained in depth at the beginning of the talk. Then, it's pointed out that the processes being employed in legal cannabis markets do not meet these standards. Somewhat makes sense under the mindset that we are still figuring things out, but still shocking that there are ZERO validated processes and yet the industry often leans heavily on remediation.
Microbial remediation as is done in cannabis is prohibited by FDA (Food & Drug Administration) and FSMA (Food Safety Modernization Act) in other industries.

So, basically, we can't eat food treated this way, but we can smoke weed that was?
"Treatment methods such as irradiation should not be used as a means to remediate cannabis contaminated above the allowed limits" - United States Pharmacopeial Convention (USP).

Yep, you read that right. Even the Pharma industry (as well as the World Health Organization, Western Growers Association, and European Medicines Agency) condemns the very practices being used daily to "fix" dirty weed so it can test below allowable limits so it can be sold to the unwitting consumers.
"If we can do it with dog food, we can do it with cannabis." Another jaw-dropper: Even the dog food industry—often suspect to many for low-quality inputs—doesn't allow remediation.

Yes, weed is treated with less regard than dog food (including the bargain bin).
"These [processes] are not making products safer, I would argue they are allowing unsafe products to pass testing and get into the hands of the consumers" - Dr. Eidem.

Straight from the Doctor's mouth, this isn't good for consumers. It's good for producers who fucked up and now need to pass testing. Read that again: they need to pass testing. They don't need to "bring a quality product to market" or "bring a safe product to market," they need to pass testing so whatever product they've got can be sold. That's scary. And part of why I rarely buy anything on market (cough, grow your own, cough).

But, any insightful presentation would not be complete if it did not prompt further questions and clarification, much of which will be accelerated by increasing legal access to research.

5 Unanswered Questions Surrounding Microbial Risks in Cannabis:

When it comes to increase risk of fungal infection among cannabis users, what percentage of those users consumed product leading up to and during the study that was commercially produced, commercially remediated (or not), or grown at home?

A follower on Twitter brought up earlier today that a homegrower without experience drying and curing could easily introduce mold and mildew into their post-harvest product. While this doesn't change the result of the overall risk, it would provide clarity into whether growing your own does increase your chances of avoiding the microbial risks associated with commercial product (or it disproves the theory and we should reconsider out homegrow efforts to be better about microbial prevention.
How do extraction methods impact micro risks? I bring this up for two reasons:
1. Solvent vs Nonsolvent: It has long been believed that certain extraction processes that involve chemical extraction (BHO, PHO, Etc.) can mitigate certain other issues (like powdery mildew and mold) on harvested material. I would be curious if this holds true, as the talk focused primarily on dry herb material, not extracts.
2. Additional Remediation Processes: Techniques such as CRC (color remediation cartridge) and distillate have long been believed to remove certain impurities and "fix" the unfixable. How do these processes (often designed for purposes other than microbial reduction) affect microbe content?
Further, how are non-inhalable products impacted (and does their process from extract to production impact those risks)?

If you're eating an edible made from BHO that was extracted from a remediated, formerly-adulterated crop, are you at risk? Is the old belief that extraction and cooking with products will "clean" that risk away? What are the risks of eating those microbial contaminants as opposed to combusting or vaporizing them? If the food industry's prohibition of the use of remediation for raw materials is any indicator, this could be concerning if low quality product is being turned into edibles and tinctures.
How can consumers identify remediated product if it is not being (or required to be) labeled as such?

The golden question here is now what? Now what can I do as a consumer to identify these practices? Some producers are labeling some processes. For example, extracts are increasingly labeled as CRC. But, inherently, if you're trying to "fix" a problem, advertising that you fixed it only advertises the problem you fixed. Which is why most brands don't say "Hey, we had to treat out crop because it had mold," they just clean it until it's clean, and sell it and hope no one notices.
What else are we mistaking adverse microbial reactions for?

For example, cannabis hyperemesis syndrome (CHS) is a big concern in the space. So are contaminants in vapes (like Vitamin E Acetate and glycols). As we learn more about potential contaminants on the raw materials that cause adverse reactions, how many problems in the past have been misdiagnosed as something else when they were really the result of high microbial bioburden?

3 Real-World Implications You Can Use Moving Forward:

Ok. So, if like me, you've now had to pick your jaw up off the floor, and are wondering what needs to happen now, here's a few suggestions:

We need state laws to align with parallel industry practices. While cannabis is not the same, smokable crops like tobacco—as well as heavily-regulated food crops—should be considered. In many cases, this is unlikely, because there's less money to be made when regulations tighten. But the need is there.
We need growers to become more familiar with proper prevention and less reliant on having a "Plan B" to fix the problem. An ounce of prevention is worth a pound of cure, as my co-author Zac likes to say.
Grow Your own! If you are at all concerned about microbial contamination and being unable to spot remediated product, there's never been a better time to grow your own (especially if you've been given the legal right to do so). Admittedly, you'll still have to work on cleanliness and ensuring you aren't creating problematic environments for mold and mildew to grow in, but you'll be in control of that process, and you'll know every aspect of every step of that plant's life from start to finish, a level of transparency you cannot count on in most of this industry.

The Hobby Grow