The term ‘mycotoxin’ is usually reserved for the toxic secondary metabolites that are produced by fungi while colonizing plants. One fungus species may produce many different mycotoxins, and several fungus species may produce the same mycotoxin. The role of mycotoxin in the infection process (pathogenesis) of plants is not fully understood. They may weaken the plants auto-defense mechanism and the fungus may use the toxins as a strategy to improve the environment for further fungal growth.
Some of the crops that are most under threat are corn, the small grain cereals such as wheat, barley, rye and oats but also crops such as peanut are susceptible to mycotoxins formation. There are some really harmful mycotoxins out there that are toxic in very low doses. For example, deoxynivalenol in cereals has a maximum admissible level of 8 parts per million, and aflatoxin in feed for dairy cattle has a maximum level of 5 parts per billion. With most mycotoxins, it is not so much the acute toxicity that is the problem, but rather the chronic toxicity. Mycotoxins are suspected to have carcinogenic, teratogenic and genotoxic effects, mostly in a chronic way in the case of human beings.
The production of toxins depends on the surrounding environment and these substances vary greatly in their toxicity, depending on the infected plant species and its susceptibility, metabolism, and defense mechanisms. Mycotoxins greatly resist decomposition or being broken down in digestion, so they remain in the food chain in meat and dairy products. Even temperature treatments, such as cooking and freezing and the production process of bioethanol (issue for use of DDGS as animal feed), do not destroy some mycotoxins. Therefor it is crucial that the seed sector tries to prevent the formation of mycotoxins in our food and feed crops.
The seed sector can contribute in two ways: first of all, breeding of resistant plant varieties against mycotoxin forming fungi and secondly, producing healthy, not fungi infected seeds. We should realize that the minimization of mycotoxin content in our food and feed is always an integrated approach: A requires a combination of agronomic measures like crop rotation; genetics like tolerant or resistant varieties and crop protection like seed treatment and foliar products to get the best result. One item that could be improved is that we need faster approval of effective tools, such as crop protection products. This would really help the seed sector, and in fact the EU consumers to bring down the level of mycotoxins.