Monitoring of mycotoxins and other contaminants in UK cereals used in malting, milling and animal feed (2012–16)

Abstract

This project looked at the occurrence of key contaminants in UK-grown cereals in UK-grown wheat, barley and oats and their co-products. The project covered samples from the 2012, 2013, 2014 and 2015 harvests intended for use in the milling, malting and animal feed industries. Samples of each type of grain were collected immediately after harvest and after storage of up to six months. Relevant contaminants were selected and a sampling programme agreed by a steering group comprising AHDB, the Trade Associations nabim, MAGB, and AIC. Campden BRI informed the steering group through "horizon scanning" of official publications and scientific and agricultural literature as well as advice from scientists from the analytical laboratories. The contaminants selected were pesticides, growth regulators, desiccants, mycotoxins (Fusarium toxins, Ochratoxin A and ergot alkaloids), pesticides, heavy metals, dioxins and chlorates.

The overwhelming majority of samples complied with legal and guideline limits. Levels of applied storage pesticides, growth regulators and desiccants were all within legal limits and levels did not vary significantly from season to season. There does, however, appear to be an increase in the use of the synthetic pyrethroids cypermethrin and deltamethrin and a reduction in the application of the organophosphate pirimiphos methyl.

The storage mycotoxin, Ochratoxin A was generally detected only at low concentrations, with mean and median values largely being determined at levels at, or just above the LOQ (0.1 μg/kg). This demonstrates that mould growth and toxin synthesis are being adequately controlled by suitable storage conditions. Levels of Fusarium mycotoxins, which in previous surveillance projects have showed significant seasonal variations, increased from 2011 to 2012 but then largely declined from the 2012 to 2015. Ergot alkaloids were generally determined at very low levels, the vast majority of samples having a median value below the method LOQ.

Selected elements were surveyed during three harvest periods on selected sample types.

Dioxins were analysed on selected AIC samples from the 2014 and 2015 harvests.