Spatio-Temporal Shifts in Climatic Suitability for Mycotoxins in Europe

Mycotoxin contamination of cereals remains a major threat to food security, as the development and toxin production of fungal pathogens are strongly controlled by climate. This study presents a continental-scale assessment of climatic suitability for three key mycotoxigenic fungi, Aspergillus flavus, Fusarium graminearum and Fusarium verticillioides, across Europe over a six-decade period from 1961 to 2020. Using daily ERA5-Land temperature and precipitation data and species-specific thermal response functions, we calculate a composite Risk Index that combines suitability for vegetative growth and sporulation. Days with index values exceeding 0.5 are classified as “risk days.” Results show a substantial increase in the annual number of risk days across Europe for all three species. Aspergillus flavus exhibits the strongest relative increase, exceeding 90 percent in several parts, together with a clear northward expansion into parts of Central Europe. By integrating these results with high-resolution maps of maize and wheat cultivation, we identify agriculturally important regions where warming has transformed fungal risk from occasional to persistent. In several hotspots, the number of risk days has doubled compared to the baseline period. This trend closely mirrors increases in the frequency of hot days above 25 °C during the growing season. These findings indicate that climate warming is rapidly intensifying and redistributing mycotoxin risk in Europe, with serious implications for cereal safety, public health, and climate adaptation strategies.