'In the air all the time': Microscopic menace prompts OHA rule, worrying pot growers

PORTLAND, Ore. (KOIN) -- Myron Chadowitz and his cousin run a small family-owned cannabis farm in Eugene. Unlike indoor cannabis grows, which use small individual pots for each plant, they said part of their secret sauce is growing cannabis in living garden beds that connect down to the native soil, utilizing natural elements of the ecosystem like flowers, wood chips, cover crop, worms, rolly pollies and garter snakes.

"We practice what we like to call 'beyond indoor techniques,'" Chadowitz said. "We're using the soil's natural biodiversity and biology to actually feed the plants from the soil side."

The farmers at Cannassentials said their techniques have led them to consistent awards and accolades for their craft cannabis.

"We've won 17 or 18 awards in those seven years," he told KOIN 6 News. "Mostly first- and second-place finishes."

You won't find any store bought fertilizers or bottled nutrients there. Everything at Cannassentials is au naturel.

But new rules from the Oregon Health Authority took effect in March 2023, mandating cannabis be tested for a microscopic mold called aspergillus.

Chadowitz said this rule is forcing many farmers to use fungicides and radiation on their cannabis.

Seri Robinson, an associate professor of wood anatomy at Oregon State University, said there is a vast misunderstanding about this invisible mold.

"Aspergillus is in the air all the time. So, at a standard airborne spur load, most people don't even know it's there," Robinson said.

The Center for Disease Control said aspergillus is very common both indoors and outdoors, so most people breathe in fungal spores every day. For people with healthy immune systems, breathing in aspergillus is not harmful.

But for people with weakened immune systems, breathing in aspergillus spores can cause an infection in the lungs or sinuses, which can spread to other parts of the body.

"Aspergillus is in the air all the time. So, at a standard airborne spur load most people don't even know it's there."

Associate Professor Seri Robinson, OSU

Any microbe is dangerous to someone with a compromised immune system, Robinson said.

"The more compromised your immune system is, the more you have to worry about those kinds of things," he said. "But most people have fairly robust immune systems and so a fungal spore here or there is completely irrelevant."

Because medicinal cannabis is often used by chronically ill patients affected by a weakened immune system, pharmaceutical regulations in other countries -- like Canada and The Netherlands -- specify these products must adhere to strict safety standards regarding microbial contamination.

Oregon is now following suit.

'Ubiquitous in environment'

Cannabis farmers say they don't stand a chance against aspergillus the way the OHA standards are written.

"It is basically ubiquitous in the environment," Chadowitz said. "It's in soil, it's in compost, it's in wood chips and basically we're breathing it all the time."

The new rule in Oregon tests for the presence of four pathogenic species, out of the approximately 180 known species of aspergillus. In order to pass, the regulation requires a sample to not have any of those four species of aspergillus detected at all.

Industry estimates say that, in general, about 10% of cannabis fails the aspergillus test after harvesting. With high taxes, historically low wholesale prices, and an inability to deduct business expenses given cannabis is still federally illegal, that 10% could be a farmer's entire profit margin.

It's the difference between harvesting next year or closing their farm and selling their license.

"Now, a grower like us who's growing in soil with compost and woodchips, we are at a much bigger disadvantage because it's ever-present in our greenhouses," Chadowitz said. "But it's affecting farms up and down the line."

Marianne Cursetjee has a cannabis farm in Damascus, Alibi Cannabis. She got into the cannabis industry early on after using it to battle cancer and chemotherapy.

Her grow is entirely indoors and uses a more traditional controlled-grow setting. Yet, she is still concerned about the impacts of this new regulation.

"There is a huge amount of uncertainty about the aspergillus and the mold and mycotoxins test," Cursetjee told KOIN 6 News. "They (the OHA) are not trying to solve a problem. It's a solution looking for a problem."

One option for farmers to eradicate this invisible fungus is to irradiate their flower with X-rays or gamma rays after harvesting.

"Who wants to smoke radiated weed? Nobody," Cursetjee said.

One peer-reviewed study from The Netherlands shows irradiation is effective at killing aspergillus and did not impact the level of THC or CBD. But it had caused the loss of cannabis terpenes. For medicinal cannabis users, terpenes offer different therapeutic values and medicinal properties.

Related research found gamma irradiation was very effective in reducing mold, but it is not environmentally friendly and requires a nuclear facility.

Another option to kill off aspergillus is using ozone. The Environmental Protection Agency said ozone is a toxic gas that is regulated -- but can be used as a disinfectant.

"That's supposed to kill the aspergillus. But once again, we're adding things that don't need to be there," Cursetjee said. "In my perspective, I come from looking at this from a medical side, I'm a medical patient. So, if there's something that I don't want to put in my body, why would I sell that?"

In Oregon, if a lab detects aspergillus on a farmer's cannabis they fail. They're given one chance to treat the cannabis flower with radiation or ozone. If the bud fails a second time, the Oregon Liquor and Cannabis Commission requires farmers to destroy it.

Cursetjee finds that unfair for outdoor farmers.

"You have one crop a year and if you destroy it, that is your entire livelihood, that is your entire income for a whole year gone in smoke," she said.

Why this is now an issue

A 2019 audit tasked the Oregon Health Authority to research aspergillus. In the absence of resources, the OHA said they collected data from other states with legalized marijuana.

At least 22 other states require there to be no or very little aspergillus detected on cannabis. KOIN 6 found there are 16 states, including Washington and Puerto Rico, that don't test for aspergillus at all.

There are remediation companies who make products that kill these unseen mold spores. Earnings estimates show the remediation companies stand to make billions of dollars from this new regulation -- especially if and when cannabis becomes legal on a federal level.

Farmers say the standard radiation machines can cost between $20,000 and $500,000.

"Talk about a play to get the small guys out."

Myron Chadowitz, Cannassentials

If this continues to be the trend, Chadowitz said small family farms like his will go extinct.

"Talk about a play to get the small guys out," Chadowitz said. "Growers are scared to even plant their crops because the price of cannabis outdoors is so cheap that the extra testing costs, the remediation costs are just too much for them to handle."

Farmers argue there are better alternatives to this current regulation, like putting warnings labels on packaging for people who are immunocompromised or using the flower in different forms, like oil.

"When you take cannabis and you extract the oil, it automatically gets rid of any molds and mycotoxins that might exist," Cursetjee said.

Officials at the Oregon Health Authority told KOIN 6 the focus shouldn't just be on remediation. They said prevention is more important and key in controlling aspergillus.

The OHA said the mold can thrive in a moist environment. Heath official said aspergillus is also very heat stable, meaning that combustion or heating cannabis to smoke does very little to kill spores before it is inhaled into the lungs.

"Testing for aspergillus ensures that the risk is lowered once the product moves to the next stage of storage or handling," the OHA said in a statement. "This isn't to say aspergillus couldn't occur further down the supply chain. It could, and that is why cannabis businesses should implement prevention measures."

OSU Associate Professor Seri Robinson said total prevention is difficult to acheive.

"If it were my lab and we said we will have absolutely no mold spores anywhere in the lab, the lab couldn't run," Robinson said. "We'd have to shut it down."

She said it's a large burden for any indoor operation to pull off, let alone an outdoor facility.

"I don't think we should ever minimize the harm that can be done by aspergillosis and aspergillus. However, it is very, very rare," Robinson said. "So it's really important to understand that we have to be safe and we have to understand that people have been hurt, but we can't go so far in the other direction that we shut down people, places, times, industries, just to control something that is poorly understood."

Because aspergillosis is not a reportable infection in the United States, the exact number of cases is difficult to determine. Invasive aspergillosis is uncommon and occurs primarily in immunocompromised people. Milder, allergic forms of aspergillosis are more common than the invasive form of the infection, according to the CDC.

This adds to the challenge of knowing if there've been any cases linked to cannabis in Oregon, the OHA said.

Back at the farms

Marianne Cursetjee is now using chlorine dioxide gas to clean her plant rooms between crops. So far she has not failed a test -- and is hoping for the best.

Myron Chadowitz recently had several batches of crop from his outdoor farm fail. He said he had no choice but to irradiate the cannabis because he can't afford to destroy the product.

Farmers fear this strict OHA regulation will shut down their industry for good. As a result, cannabis growers across Oregon have a public campaign and are bringing a lawsuit to get an emergency stay on this law.

Chadowitz said the lawsuit is "so that we can gather more research in the state, can gather research on are the lab results effective, or is this actually something that we should be scared about?"

Meanwhile, OHA does not believe it is in the interest of public health to pause aspergillus testing.

Though he's not required to, he is now putting a disclaimer on his flower, notifying cannabis consumers it's been irradiated.

Consumers, he said, have the right to know what they're smoking -- for good or bad.