Vomitoxin, also commonly known as Deoxynivalenol, or DON, is one of the most common types of Mycotoxins typically found in corn and other small grains such as wheat, oats, barely, rice, and more. This substance is produced by certain species of fungi within the large group of filamentous fungi known as Fusarium, and usually infects the crop while in the field or during storage. The most common culprit is Fusarium graminearum, also known as Gibberella zeae, which is known to cause GER or Gibberella ear rot.

GER infections often occur in the field when the weather is warm and humid at inopportune times, and can increase when stored in poor conditions. According to the Agricultural Safety and Health Program with Ohio State University, for corn, the infection occurs during the weeks after silk emergence. Their study also mentions that, if infected, the production of vomitoxin within the crop will continue even if subsequent weather conditions are not as favorable to the growth of the mold and ear rot on the outside of the ear.

Having vomitoxin in the corn or grain produced can cause a variety of health problems for both humans and animals. Unfortunately, many food processing methods typically do not reduce or remove vomitoxin, and may even cause the parts per million to increase depending on the method used. According to this study in the National Library of Medicine, there is some evidence that cooking food products in water can reduce some of the DON levels as some of the toxin would leak into the cooking water.

In humans, DON can cause short-term nausea and vomiting, as well as diarrhea, abdominal pain, headaches, dizziness and fever. In most cases, the symptoms are fairly light, though larger doses can cause more severe cases of the common symptoms, as well as more dangerous additional symptoms.

In animals, too high of a dosage of vomitoxin in the diet can cause several adverse affects. These affects range from feed refusal from livestock (especially in pigs), vomiting, reduced weight gain, reduced productivity, and more.

Not only is vomitoxin problematic for consumption, it can also lead to problems and penalties in regards to your harvest. Some grain elevators will test for DON, and having problematic parts per million ratios can lead to discounts, and rejection of the crop. Infected crops also tend to be smaller and have damaged kernels that tend to be more fragile. Heavily infected corn and grains often break very easily during harvest and transport, breaking down into a dust and fine particles. These breakdowns tend to be more contaminated with the problematic mycotoxins than the rest of the grain itself.

Finally, DON can also affect seeds as well. According to Andrew Friskop, and Joel Ransom from North Dakota State University, the fungus Fusarium Graminearum that causes vomitoxin can also cause seedling blight and root rot if the seed source is too heavily infected.

According to The Agricultural Safety and Health Programs article from Ohio State University on Vomitoxin in Corn Grain Bins, there is currently no commercially available treatment for reducing vomitoxin levels in stored corn and grains. In fact, poor storage can cause an increase in toxin levels. However, there are a few things that can be done to protect already harvested grain, and help prevent the Gibberella Ear Rot infection from occurring to start with.

For harvested corn and grain protection, keeping the crop at a low moisture level in a cooler temperature can help. It is also highly suggested that clean bins be used for each lot, and to clean bins and storage units between different lots to help prevent some cross-contamination. Taking meticulous care of infected grains can help keep the toxicity levels from increasing, and making sure to keep clean grain away from infected can help prevent vomitoxin levels in other grain lots.

Additionally, when harvesting grains with a known infection, it is suggested to use combine settings that are gentler on the crops and minimize damage to grains. This helps prevent the spread of infected fines and dusts which can increase DON numbers and affect healthy parts of the grain. This article on Harvesting and Handling Ear Rot Affected Corn from Ohio State University has several insights on proper combine settings to help with harvesting infected grains.

Finally, certain steps can be taken to reduce the risk of Gibberella from infecting crops in the field. Certain seed varieties can be used that have a resistance to DON, and certain fungicides can help depending on the scenario. Finally, maintaining a good crop rotation between host crops and non-host crops is a helpful management practice that can prevent early infection. For example, planting wheat after corn can increase the risk of the wheat being infected.

Unfortunately, even when the best practices are implemented correctly, It is still possible to have DON levels exceeding the advisory levels set by the FDA during very favorable weather conditions for the development of the fungus. For more information on how your crop insurance interacts with vomitoxin, contact your Silveus Insurance Agent.

Take a look at the Fusarium Risk Tool designed to help estimate Fusarium risk levels created by Ohio State University, PennState Center for Environmental Informatics, K-State Research and Extension, and the U.S. Wheat and Barely Scab Initiative!