What exactly is this fungus—and what risks does it pose to U.S. agriculture and public health?
A fungus called Fusarium graminearum has made headlines after two Chinese researchers were charged by the FBI for allegedly smuggling it into the United States as a potential agroterrorism agent.
But what exactly is this fungus—and what risks does it pose to U.S. agriculture and public health?
A Common Cause of Crop Disease
F. graminearum is a concerning fungus, as it can contribute to billions of dollars in agricultural losses, Gary Bergstrom, professor emeritus at Cornell University specializing in plant pathology, told The Epoch Times.
The fungus typically infects crops during the flowering season in rainy weather, Bergstrom said. It affects kernel development in grains and can significantly reduce yield if not treated. It can also contaminate crops with mycotoxins—toxins produced by fungi that can cause poisoning in humans and livestock when they eat them.
For example, the fungus can infect corn either through the stalk or through the top of the ear, causing “ear rot.” The infection leads to mold growth in kernels, significantly reducing yield and producing inedible corn.
F. graminearum releases four different mycotoxins, the most well-known being deoxynivalenol (DON).
DON, also called vomitoxin, can induce vomiting and food poisoning-like symptoms in humans and animals.
Another toxin is zearalenone (ZEA), which disrupts hormonal function and may cause infertility in livestock, especially pigs.
The other two mycotoxins are nivalenol and fusarenone X, both of which are toxic to cells and can suppress the immune system.
Poisoning in Humans Difficult to Detect
In humans and livestock, mycotoxins from F. graminearum can cause vomiting, liver damage, and reproductive defects.
Most research, however, has focused on animals, as it is very difficult to detect poisoning caused by F. graminearum mycotoxins in humans. In livestock, poisoning is typically identified by testing the feed rather than the animal itself.
Dr. Jerrold Leikin, adjunct clinical professor in the Division of Environmental and Occupational Health Sciences at the University of Illinois at Chicago, said that it is practically impossible to detect F. graminearum toxins in humans.
“It’s almost impossible to diagnose,” Leikin said. “Virtually all hospitals don’t have the ability to diagnose this particular type of food poisoning.”
The main concern with F. graminearum is DON.
The risk of a person being poisoned by F. graminearum products is very low, as the FDA regulates allowable levels of DON in food.
Flour made for human consumption must not exceed DON levels of 1 ppm, while allowable levels for livestock range from 5 to 10 ppm. DON does not break down with heat, though processing grains into flour may remove some DON in the sample. Flour mills typically grind incoming wheat and test for DON; if levels exceed certain thresholds, the mill will not purchase the grain, Bergstrom said.
If a person accidentally consumes food contaminated with F. graminearum mycotoxins and receives a high dose, treatment would involve supportive therapy, Leikin said. This would include adequate hydration and replenishment of electrolytes.
By Marina Zhang
