Rising temperatures because of climate change are increasing the risk of human exposure to mycotoxins, according to the European Environment Agency (EEA).

A briefing published by the agency looked at health concerns around mycotoxins and how to tackle their spread and prevent contamination. Mycotoxins can contaminate crops, food, and feed.

EEA said mycotoxins pose significant health risks. The toxins can disrupt hormones, weaken the immune system, damage the liver and kidneys, increase the risk of miscarriage, harm unborn children, and act as carcinogens.  

Young children aged 1 to 3 and infants under 12 months old are especially vulnerable due to their higher food intake relative to body weight, as are pregnant women and workers in the agricultural, food and feed sector.  

According to a European human biomonitoring project focused on chemicals, 14 percent of the adult population in six studied countries are exposed to deoxynivalenol (DON) at levels that are considered harmful to health. This mycotoxin type is frequently found in wheat, maize and barley in temperate regions.  

Climate impact
The briefing focused on DON but other mycotoxins are aflatoxin B1, Fumonisin B1, zearalenone, and ochratoxin A. The EU’s regulation has limits for aflatoxin, ochratoxin A, DON, zearalenone, fumonisins (B1 and B2), and patulin in some foods.

People are exposed by eating contaminated food such as grains and cereals, and products which contain them like bread or pasta. Mycotoxins are absorbed by plants during growth or after harvest and can remain in food even after washing, cooking or processing. This is because some are resistant to heat and typical food preparation methods. Some of the fungi that produce mycotoxins are not visible, or detected by smell or taste. 

EEA said climate change is altering fungal behavior and distribution, potentially increasing the risk of exposure to these toxins. A warmer and more humid climate across European regions is promoting a higher prevalence of mycotoxins.

For maize, climate-induced aflatoxin contamination has been linked to food safety concerns, which could also affect international trade. Post-harvest controls such as cooling, cleaning, sorting, and packing steps are also important.

Potential changes
Extreme weather, such as heavy rainfall or prolonged droughts, increase the stress that plants are exposed to, making cereals like maize vulnerable to fungal infections and mycotoxin contamination. Increased crop contamination can lead to lower yields, with associated economic losses. 

The highest risk of climate change-induced mycotoxin contamination is expected in developed countries with moderate climates. Certain mycotoxins are expected to become more prevalent at higher temperatures and in humid conditions. Contamination from multiple mycotoxins is expected to increase in crops, escalating human dietary exposure.

Producers may start growing different crops better suited to the changing environmental conditions. According to the briefing, this may have unexplored consequences for food safety.

The EEA said future actions to counter mycotoxin contamination could include breeding crops resistant to fungal infection; good agricultural practices, like adapting to environmental conditions including crop rotation to regenerate soil fertility and minimizing the carry-over of mold from one year to the next; as well as using biological controls and predictive models.