Ergot mycotoxins

Ergot mycotoxins

By Nick Byrd - 4 October 2016

The European Commission is intending to propose maximum levels for ergot alkaloids in unprocessed grain in 2017. Ergot is the name given to the sclerotia of the fungus Claviceps purpurea, which is widespread and infects many cereals, including wheat, rye, barley and oats, and the related Claviceps fusiformis, which infects millet. Ergots are hard, dark tuber-like bodies which are visible to the naked eye and produce mycotoxins. The sclerotia are harvested together with the cereals and can lead to contamination of cereal-based food and feed products with ergot alkaloids.

We have developed a sensitive mass spectrometry-based method to detect the six major ergot alkaloids as defined by EFSA (ergometrine, ergotamine, ergosine, ergocristine, ergocryptine and ergocornine) and their corresponding epimers at levels as low as 1μg/kg. The validated method has been accredited by UKAS to ISO17025. We are one of the few companies currently providing this testing service in the UK, and have been carrying out ergot testing for several years.

Commission Regulation (EC) No 1881/2006 on contaminants in foodstuffs was amended in 2015 and sets a maximum level for ergot sclerotia in unprocessed cereals of 0.5g/kg. Compliance with the maximum level for ergot sclerotia does not necessarily guarantee the safety of the food as regards the presence of ergot alkaloids.

Ergots produce mycotoxins composed of up to 40 related alkaloids, collectively called ergolines. The toxicity of ergot alkaloids has been recently reviewed by EFSA. They have moderate acute oral toxicity and can also cause issues via long-term dietary exposure. Ergot alkaloids are neurotoxic and act on several neurotransmitter receptors.

Ergots are larger, darker and less dense than grain. The industry has almost a zero tolerance for presence of ergot sclerotia in grains. Any sclerotia visible on inspection will lead to the entire consignment of grain being rejected. Although grains can be sorted by colour or density to remove sclerotia, which results in a considerable reduction in the levels of ergot alkaloids in the grain, the toxins can still remain on the grain.

Ergot can infect a range of commercially important cereals in Europe and North America. Livestock which consume grain contaminated with ergot can also be affected. While human epidemics are now very rare, incidents due to contaminated animal feed do still occur because the sclerotia can concentrate in the by-products of cereal milling.

In June 2012, following a request from the European Commission, EFSA's Panel on Contaminants in the Food Chain (CONTAM Panel) delivered a scientific opinion on the risks to human and animal health related to the presence of ergot alkaloids in food and feed.

EFSA has derived a group acute reference dose (ARfD) of 1μg/kg body weight and a group tolerable daily intake (TDI) of 0.6μg/kg per body weight per day. EFSA has estimated the chronic dietary exposure in the adult population in the EU to range between 0.007 and 0.08μg/kg body weight per day for average consumers and 0.014 and 0.19 μg/kg body weight per day for high consumers.

Our method will help manufacturers working with cereals and grains to maintain the quality and safety of their products.

Nick Byrd, Head of Chemistry and Biochemistry
+44(0)1386 842187

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