What are mycotoxins?
Some fungal species can grow on crops and foodstuffs and produce toxic chemicals. Of widely varying toxicity to humans and animals, these chemicals are called mycotoxins. In cereals, mycotoxins can result from fungi that either develop from field-borne infections (fusarium mycotoxins and ergot alkaloids) or in stored crops (ochratoxin A).
There are five fusarium species and two microdochium species that infect cereals and may cause ear or head blight. In the UK, the main mycotoxin-producing species are F. culmorum, F. graminearum and F. avenaceum. Microdochium species do not produce mycotoxins. Information on symptoms, life cycle, importance, risk factors and management of the pathogens that can cause ear or head blight can be found in the cereal disease encyclopaedia.
There are legal limits for fusarium mycotoxins deoxynivalenol (DON) and zearalenone (ZON) in wheat intended for human consumption and guidance limits for feed grain.
The owner (farmer, merchant or processor) is legally obliged to ensure grain is safe for human consumption. Depending on end use, processors may require a lower limit at intake than the legal limit for unprocessed cereals to ensure finished products conform to legal limits.
Download the risk assessment
Mycotoxin rainfall risk tool
Rainfall-related mycotoxin risk assessment scores can now be calculated automatically with this tool.
Covering thousands of sites across England and Scotland, the map-based tool also shows how much rain has fallen during the critical winter wheat flowering and pre-harvest periods.
- Read AHDB guidance on fusarium mycotoxins in cereals
- Follow best practice to minimise fusarium mycotoxins in cereals
- Use the publication (order a printed copy) or the online tool to assess risk of fusarium mycotoxins
- Assess risk pre-flowering and consider T3 fungicide (ear spray)
- Take accurate measurements of rainfall at flowering and pre-harvest
- Calculate final risk score at harvest and record on grain passport
- Check purchaser requirements to determine whether mycotoxin testing is required
Agrochemical residues, mycotoxins and other major contaminants in cereals and co-products have been monitored independently since mid-1980s. Find out about our research that aims to help ensure the safety of the UK grain and its end-products.
AHDB information should be read in conjunction with the UK Codes of Practice produced by the Food Standards Agency.
Managing mycotoxin risks
The following resources will help you assess and manage mycotoxin risk. They will also help you to obtain composite and representative samples for testing for DON and ZON (where required by the end-user).
Pre-flowering risk scores
Flowering to harvest risk scores
A robust foundation to instil confidence
While growers strive to achieve quality and other criteria in cereal grain, it’s important these efforts don’t result in undesirables creeping in. CPM reports on the research that monitors contaminants.
A robust foundation to instil confidence (CPM article, October 2016)