The contamination of plants and crops with moulds has been a long standing problem in agriculture. Mycotoxins are toxic secondary metabolites of moulds that decrease yields and the marketability of crops, also causing decreased growth, reproductive disturbances and disease, even mass deaths when fed to animals.
Mycotoxin tests can be classified based on various characteristics but generally can be grouped as rapid methods and reference methods. Rapid methods include ELISA tests, immunochromatography and fluorometry. Reference methods for mycotoxins are based on HPLC assays that can be complemented by various methods of detection (e.g. UV, FLD, MS, MS-MS).
Test strip methods are quick and easy to use and play an important role in testing grains during the filling of stores and outloading, and are available as both qualitative and quantitative tests. These tests are validated for the testing of simple sample matrixes, which means they are recommended for performing screening tests on raw materials.
Reference methods are recommended for testing more complex matrixes.
The laboratory of Bonafarm-Bábolna Takarmány Ltd. is equipped with state-of-the-art UHPLC MS-MS equipment capable of giving quick and precise information regarding the following toxins in the submitted samples: DON, zearalenone, aflatoxins, HT2, T2, nivalenol, fumonizins, ochratoxin, DAS, deoxynivalenol-3-glycoside.
Whichever method we chose to determine mycotoxins, sampling plays an important role, and the requirements of sampling are laid down in various regulations and decrees.
The procedure of sampling involves taking a small representative sample from a large batch in a way that the ratio and the distribution of the tested analyt remains the same in the sample as it was in the tested batch. Our aim is to be able to draw valid conclusions regarding the given batch based on the test results of the sample.
Mycotoxin testing is a complex procedure consisting of three elements:
- sampling (taking a small representative sample from a big batch)
- grinding, the preparation of the sample
- extraction, when mycotoxins are extracted from the analytical sample, and their amount is determined
Many scientific studies are aimed at analysing sampling, as it is the greatest source of error when testing for mycotoxins. (1) This means that the person extracting the representative sample for mycotoxin testing has great responsibility.
We perform thousands of accredited tests in our laboratory every year.
The most contaminated grain based on our data since July 2022 was maize.
We found aflatoxin in concentrations above the threshold in 48% of the tested samples, with an average concentration of 0.015 mg/kg. We detected DON in 30% of the tested samples, the average concentration of which was 0.69 mg/kg. Testing for fumonisin was requested by our partners for 10% of the samples, mainly for batches that were probably not of Hungarian origin. We found fumonisin in 90% of these samples, at an average concentration of 3.21 mg/kg. We also detected other toxins in some of the tested samples, namely ochratoxin, T2, HT2 and zearalenone.
When testing barley, we found DON in 25% of the batches, with an average of DON content of 0.64 mg/kg. In a few cases we also detected zearalenone, T2 and HT2.
Based on our experience, wheat is the “winner” this season, with DON detected in 27% of the samples, with an average value of 0.18 mg/kg. The amount of other toxins exceeded the limit of detection in only a few samples.
Every year poses different challenges for both our partners and the testing laboratories in terms of mycotoxin testing. We are planning to expand the number of mycotoxins tested, so we can give our partners more information regarding the quality of the samples and support them better in their decisions.
(1) Reference:
Donnelly, R.; Elliott, C.; Zhang, G.; Baker, B.; Meneely, J. Understanding Current Methods for Sampling of Aflatoxins in Corn and to Generate a Best Practice Framework. Toxins 2022, 14, 819. https://doi.org/10.3390/ toxins14120819
Bea Herczig
Head of Laboratory Division
Bonafarm-Bábolna Feed Ltd.
