Global occurrence of mycotoxins in the food and feed chain: facts and figures

Mycotoxins are ubiquitously present in agricultural commodities, such as cereals and oil seeds. If ingested in sufficiently high concentrations, they exert severe toxic effects in humans and animals. In 2004, a survey programme was launched to assess the extent of mycotoxin contamination in feed and feed raw materials. Since then, over 19,000 samples have been analysed and more than 70,000 individual analyses have been conducted. While it is difficult to infer any long-term trends on a global level, the data confirm that high mycotoxin contamination is often linked to unusual weather. Overall, 72% of the samples contained detectable amounts of aflatoxins, fumonisins, deoxynivalenol, zearalenone or ochratoxin A. Co-contamination with two or more mycotoxins was detected in 38% of the samples. In most cases the concentrations were low enough to ensure compliance with EU guidance values or maximum levels. However, co-contaminated samples with concentrations below guidance and maximum values might still exert adverse effects due to synergistic interactions of the mycotoxins. Emerging mycotoxins and masked mycotoxins may also contribute to the overall toxicity of the feed and their presence is frequently detected with multi-mycotoxin LC-MS/MS. Since by-product feeds, such as distillers dried grain with solubles, often concentrate the mycotoxins of the original substrate, they contribute excessively to the overall contamination of feed rations and therefore need special attention. Regarding food the situation is quite similar: low level contamination is frequently observed in official controls but maximum levels are rarely exceeded in developed countries. As it is very difficult to remove mycotoxins from contaminated commodities, preventing them from accumulation in agricultural commodities is the most effective strategy to combat the problem. Preventive measures range from crop rotation and resistance breeding to inoculation with microbial antagonists. Nevertheless, excessive mycotoxin levels may occur despite all preventive measures. Therefore, continuous monitoring is essential and efficient detoxification strategies are needed to deal with such outbreaks.