Affected horses display symptoms such as blindness, head butting and pressing, constant circling and ataxia, followed by death. In swine, fumonisin attacks the cardiopulmonary system, causing pulmonary edema and liver and pancreatic lesions. Fumonisins have been linked to cancer in humans. Fumonisin can occur in any geographic location where corn is grown. It is considered to be prevalent in corn.
Higher concentrations can occur when conditions are favorable.
Since 1994, outbreaks of fumonisin contaminated corn have been reported in Arizona, Indiana, Kentucky, North Carolina, South Carolina, Texas and Virginia. Grain contaminated with fumonisin levels higher than 50ppm are usually blended or destroyed. The molds that produce fumonisin can be destroyed in food and feed, but the toxin, which is responsible for the illnesses, cannot be removed from the product. To help prevent mold and toxin formation, feed should be kept fresh. Leftover feed should be removed from bunks and mangers before fresh feed is added.