“A Paradise for Mold” - Report Highlights Need for Food Safety Training in Cannabis 

Cannabis testing laboratories in many states are underreporting contaminants, a new Wall Street Journal analysis has found.  

The analysis examined more than two million mold-testing results from nine states and found that “a disproportionate share of the samples were reported to contain levels of mold just under legal limits compared with the share of samples containing levels of mold just over legal limits.” 

One such contaminant, Aspergillus, is a type of mold that can be highly toxic to users, especially those with compromised immune systems. Citing a 2020 review of insurance claims, the Journal reported that cannabis users are almost four times as likely as non-users to be infected with fungi, including Aspergillus.

Safety incidents involving microbial contaminants are quite common in the cannabis industry. Out of 59 cannabis recalls in California in 2024, 25 involved the presence of Aspergillus.  

The Journal wrote that “the improbable pattern suggests tainted samples are being cleared for sale, statistical experts said. The findings reveal a system that isn’t reliably monitoring for dangerous substances in legal marijuana.”

“A system that doesn’t play by the rules”

Interviewed by the Journal, University of Colorado Environmental Engineering Program senior researcher Tess Eidem said that marijuana growers, testing labs, and regulators are exposing cannabis consumers to dangerous contaminants. 

“There’s no way to know what’s going on when you get a system that doesn’t play by the rules,” Eidem said.

The analysis examined mold-testing data from 18 states ranging from 2014-2024. The paper found that labs in Colorado, Massachusetts, and Rhode Island were four times more likely to post lab findings that were just under the legal limit than ones that were just over the limits. 

The Journal also found that labs that gave out more passing grades on cannabis samples received more business. According to the findings, labs that reported more cases of contamination received 50% fewer testing samples over the following year than labs that gave out more passing grades. 

“Hazy Standards”

The Wall Street Journal finds fault with what it refers to as “hazy standards” on the maximum yeast and mold content in cannabis and the methods that labs use for testing. But while the article cites the shortage of research on marijuana cultivation and the lack of universal standards for cannabis, there are several food industry safety guidelines that cannabis companies can implement to make a major improvement to safety.  

The Journal article discusses the issue of airborne mold in cannabis processing facilities, largely spread by grinding machines. The article quotes a coworker of Lorna McMurrey, a Trulieve employee who died in 2022 at age 27 after suffering an asthma attack at the processing facility where she worked. The coworker said that employees often ran the machine without a filter and wore bandanas as face coverings instead of sufficient personal protective equipment (PPE). 

How Food Industry Safety Systems Can Help in Cannabis 

The proper use of PPE is an essential guideline in a number of food industry safety standards, including the Safe Quality Food (SQF) management system. Among other requirements, to receive SQF certification, companies must implement a food safety management system based on the guidelines of Hazard Analysis and Critical Control Points (HACCP).

For decades, HACCP has helped countless food companies identify and mitigate biological, chemical, and physical threats to food safety. The first step in implementing a HACCP plan is to conduct a hazard analysis to find which significant hazards exist in the workplace and are likely to cause injury or illness if not controlled. Companies must then determine the critical control points where food safety hazards can be mitigated.

HACCP takes a preventative approach to food safety that can help prevent workplace safety incidents in cannabis.

In a Rootwurks interview last year, HACCP expert Kathy Knutson said “It used to be in the food industry, it was all about putting out fires and production would move along, and then there would be a problem and everyone trying to figure out what to do. Now we sit down with our HACCP team and think ahead as much as possible about what could go wrong.”

Knutson said that the hazard analysis requirement of HACCP can help companies spot potentially harmful contaminants like mold and ensure they don’t get into finished products. And the critical control point can help companies establish the “kill step” to remove pathogens during the production of cannabis edibles - just like is done in the food industry. 

HACCP plans also require constant monitoring procedures to ensure all bases are covered, the establishment of corrective actions for deviations from the HACCP plan, and verification procedures to ensure safety measures are implemented. 

But just like these guidelines help protect food companies, they can also help cannabis companies identify and mitigate workplace hazards that can lead to contamination and product safety recalls.

“Of the 40 states that have medical cannabis codes, maybe a handful require a HACCP plan. Over time there’s just going to be more and more states that require industry best practices and this includes having and implementing a HACCP plan.”

How Food Industry Safety Training Can Protect Cannabis Companies

Safety training is essential in the food industry because it can help companies avoid recalls and the steep costs and devastating harm to brand reputation that result.

By implementing environmental monitoring training, cannabis companies can teach employees how to ensure a facility is properly cleaning equipment and work services to prevent contamination. The basic principles of food defense can also help protect cannabis products from seed to sale. Understanding the steps needed to prevent contamination and foodborne illness can help cannabis companies keep their workplaces and products safe - just as they can help food companies.

In addition, basic fundamental food safety requirements like personal hygiene training and training on sanitary personal protective equipment help establish a safety culture that makes product safety incidents less likely to occur, and easier to mitigate.

On our e-commerce site “The Wurkshop,” we feature dozens of safety training courses designed to help professionals in the food and cannabis industries build safer workplaces and products. In addition to our cannabis-specific training, industry professionals can order our food industry training courses on-demand individually on the Wurkshop, or by purchasing the Food Safety 101 bundle, which features the following 13 courses together at a reduced price:

• Environmental Monitoring Program
• Food Defense Basics 
• Food Fraud 
• Handwashing
• Introduction to Food Allergens 
• Introduction to Food Safety Systems 
• Introduction to FSMA Preventive Controls 
• Introduction to GFSI 
• Introduction to HACCP 
• Personal Hygiene
• Preventing Contamination
• Preventing Foodborne illness 
• Sanitary Personal Protective Equipment

For more in-depth safety training, cannabis professionals can take our Basic HACCP Certification Course. At only $99, it is the most affordable certification course accredited by the International HACCP Association.

All of these courses provide valuable safety training for cannabis industry professionals, to help them create a culture of safety and protect their customers, products, and employees.