KNOXVILLE, Tenn. (WATE) — A team of researchers, including a University of Tennessee professor, is urging more evaluations of medical cannabis use after fungi and mycotoxins found in cannabis and hemp flowers could cause health risks to people, especially those who are immunocompromised.

“It started because I became very interested in fusarium in hemp, and we started to see that there could be some potential problems with some of the fusarium mycotoxins,” Kimberly Gwinn, professor of entomology and plant pathology at the University of Tennessee Institute of Agriculture, said in an interview with WATE 6 On Your Side. “That has been confirmed by researchers at the University of Kentucky, and we are now just kind of saying, ‘this is something we should look at’ – we’re not saying it’s a huge problem, we’re not saying that it’s something that people who use these products should be concerned about right now, but we’re saying is, ‘we need to take a good look at this and we need to make sure that we can make great recommendations for our regulators.'”

Fusarium is a type of fungus that can cause wilting in plants. There are different types of fusarium, and Gwinn has co-authored another study published in January 2022 about its effects on Cannabis sativa.

But in this recent study, published this month in “Frontiers in Microbiology,” Gwinn and the team of researchers discussed different fungi that can infect the plants and produce mycotoxins, and also reviewed regulations and assessment methods of the contaminants.

“Although fungi and mycotoxins are common and well-studied contaminants in many agricultural crop species, they have been generally under-studied in cannabis and hemp,” an excerpt from the article states. “This is partly because human health risk assessment methodologies used to regulate food and pharmaceuticals have yet to become standard for the emerging cannabis and hemp industries. Additionally, the wide range of consumer uses of cannabis and hemp flowers, including for medical use by patients with susceptible conditions, makes it uniquely challenging to assess and manage human health risk of these contaminants.”

The researchers argue in the article that there is a growing need for more studies of potential health risks after the increased legalization of cannabis for various uses.

 “A major hurdle faced by cannabis and hemp industries is addressing the disconnect between production-related issues and human safety issues,” the article states. Recreational use of hemp and cannabis is common in many areas and all case studies linking cannabis use and fungal infections, except one, involved patients who were immunocompromised. The authors suggest a potential solution is “to reduce potential harm to medical users of cannabis from toxigenic fungi is to develop a two-tier system that distinguishes products intended for medical and recreational use.”

The recent study was published in a peer-reviewed journal “Frontiers in Microbiology” and was researched and written by Kimberly Gwinn, professor of entomology and plant pathology at the University of Tennessee Institute of Agriculture; Maxwell Leung, assistant professor, and Ariell Stephens, graduate student, both from the School of Mathematical and Natural Sciences at Arizona State University; and Zamir Punja, professor of plant pathology/biotechnology at Simon Fraser University, Burnaby, British Columbia, Canada.

“We wrote this article to bring these issues to the attention of the scientific, medical, and regulatory communities. We hope to encourage further research in this area, particularly in the areas of mycotoxins in product. Better data and public access to data will allow us to fully evaluate these risks and subsequently ensure safe products for consumers,” Gwinn said.

Gwinn also said that regulations on cannabis and hemp are on a state-by-state basis, so there isn’t a unifying regulation on the plants. She did say that most go by a total mold count.

“We’re at the beginning, we’re trying to find out if some of these fungi make toxins and we’re trying to find out where these go in the distribution of these compounds,” Gwinn said. “We’ll be doing a lot of research on it, it’s not something that makes anyone say oh I shouldn’t take this right now, but we want to make sure that we are giving the best products that we can to the consumers in Tennessee.”

Gwinn also said that she has been interested in hemp in Tennessee since it was allowed to be grown; as it was the first time in her career that she was able to go into a new crop that had little to no information on it. So they started looking at the diseases in hemp that occur in Tennessee. She spoke at the Society of Toxicology meeting in Nashville last spring and she said there was so much interest in the topic that she and the team of researchers decided to write a review paper on their ideas – for either support or otherwise.

“We just wanted to get that research going and we want to make sure that we are doing the best that we can for our consumers,” Gwinn said.

The difference between hemp and marijuana, although both are derived from the same species of cannabis plant, lies in the way their chemical formulas are arranged, according to WebMD. Marijuana contains much more of the psychoactive compound THC (tetrahydrocannabinol) than hemp, while hemp contains a lot of CBD (cannabidiol).

In Tennessee, recreational and medical marijuana use is illegal; but low levels of THC in products like hemp-derived cannabinoids, as well as the growth and use of hemp with a license, are approved. In January 2022, the Tennessee Department of Agriculture announced it had gained approval from the U.S. Department of Agriculture (USDA) for its Tennessee State Hemp Plan, which was approved in December 2021.