Mycotoxins: How climate change is affecting crops

  • 10th January 2017
  • by secretary
Emerging Issues of Environmental Concern
May 2016. UNEP, 35 pages

20 May 2016 – From the worrying rise in zoonotic diseases around the world to an examination of how climate change is increasing the toxicity of crops, this UNEP report of last year seeked to highlight a number of the world’s key emerging environmental issues.

UNEP’s Frontiers report identifies, highlights and offers solutions to six emerging issues, including the threat to human health posed by the alarming amount of plastic waste in our oceans and the crucial role the world’s financial sector can play in driving the planet to a low-carbon, resource-efficient future.

Aflatoxins, which are fungal toxins that can cause cancer and stunt foetal growth, are another emerging problem in crops. The risk of aflatoxin contamination, especially in maize, is expected to increase in higher latitudes due to rising temperatures. A recent study predicts that this toxin will become a food safety issue for Europe, especially in the most likely scenario of a 2oC rise in global temperatures.

4 November 2016. CTA Spore Magazine. Mycotoxins: How climate change is affecting crops. Agricultural yields are not the only thing under threat from climate change. A warmer climate could also make staple food crops more toxic.

The UNEP report focuses in particular on mycotoxins, a type of toxin produced by fungi that contaminate plants. There are said to be around 400 different types of mycotoxin, the most well-known of which are aflatoxins, ochratoxin A and fumonisins – strains found most commonly in maize, wheat, sorghum and groundnuts. UNEP estimates suggest that 4.5 million people will be exposed to mycotoxins in developing countries by consuming foodstuffs without quality control.

Around 40% of cases of liver cancer in Africa are said to be attributable to aflatoxins. This is the most pressing health concern in hot, humid countries. (…) There is a pressing need to promote best-practice principles among farmers to take action further up the food chain. We already have a number of simple techniques to reduce this type of contamination, such as drying seeds properly and avoiding storing them directly on the ground. Sadly, many countries lack the funding required to train farmers.” Didier Montet, food safety specialist at CIRAD

“One of the effects of climate change is an increase in the risk of plant contamination. When a plant is stressed and in poor health – such as during a heatwave or drought – it can become more vulnerable to fungal infections. Some types of fungus also infect plants via wounds caused by insects – another phenomenon that may well become more common as the climate heats up”. Catherine Bessy, food safety expert at FAO.