Mycotoxins pose a significant threat to food safety, animal health, and the overall well-being of both humans and animals. The global impact of climate change on mycotoxin prevalence is becoming increasingly evident, leaving a profound imprint on agricultural practices, and necessitating urgent attention.
Applications Manager
Randox Food Diagnostics Ltd.
Climate change is casting a dark shadow over agricultural landscapes. As temperatures rise, precipitation patterns shift and extreme weather events become more frequent, the prevalence of mycotoxins – toxic substances produced by fungi – is escalating. Three of the main mycotoxigenic fungi affected by climate change are from the genus Aspergillus, Fusarium and Penicillium. The ability of mycotoxigenic fungi to respond to climate change has induced a shift in their geographical distribution and the pattern of mycotoxin occurrence. Mycotoxins pose a significant threat to food safety, animal health, and the overall well-being of both humans and animals. The global impact of climate change on mycotoxin prevalence is becoming increasingly evident, leaving a profound imprint on agricultural practices, and necessitating urgent attention. Research data has revealed that increased global temperatures, drought stress, and CO2 levels have a measurable impact on Aspergillus flavus resulting in higher Aflatoxin B1 production.
Mycotoxin co-contamination occurs when different fungal species produce various mycotoxins, or when a single fungus produces multiple mycotoxins simultaneously. In a global study, 74,821 feed samples were collected from 100 countries from January 2008 to December 2017. Results of this survey indicate that co-occurrence of mycotoxins is the rule rather than the exception. Consequently, the toxicological effect of frequently detected mycotoxin mixtures [most importantly combinations of Deoxynivalenol (DON), Zearalenone (ZEA), and Fumonisins B1,2,3 (FBs)] should be investigated more closely. This is paramount for dietary exposure to concentrations commonly detected in feed.
These combinations of mycotoxins can have detrimental consequences on animal health. Animal species vary in their susceptibility to different mycotoxins. Poultry is more susceptible to Aflatoxin B1,2, G1,2 (AFBs), T-2/HT-2 Toxins, Ochratoxin A (OTA) and FBs, while swine are most affected by AFBs, ZEA and T-2/HT-2 Toxins. Therefore, tailored feeds for different animal species are vital as they account for specific nutritional requirements, digestive physiology, and susceptibility to mycotoxins. To protect animal health, regulations have been set stipulating maximum levels of mycotoxins in feed and feed products. By formulating and testing feeds to lower mycotoxin risks and meet the unique needs of different animals, it becomes possible to minimise the adverse effects of mycotoxin co-contamination and ensure optimal health and performance.
The list of regulated mycotoxins includes AFB1,2, G1,2, OTA, DON, ZEA, FBs, and T-2/HT-2 Toxins. Diacetoxyscirpenol (DAS) has been shown to have similar effects as T-2/HT-2 Toxins in animals. Paxilline (PAX), on the other hand, has tremorgenic activity and is a selective and reversible blocker of the smooth muscle high conductance calcium-activated channels. The need to comply with international mycotoxin regulations for feed, and to protect livestock from mycotoxin exposure has necessitated a multi-mycotoxin approach to feed testing. Randox Food Diagnostics Ltd. has developed immunoassay-based Biochip Array Technology (BAT) for the accurate and specific detection of all regulated mycotoxins in a single run. BAT is designed as a mycotoxin detection array and is presented in three formats i.e., Myco 6, Myco 7 and Myco 9 detecting six (6), seven (7) and nine (9) mycotoxins, respectively. The Myco 9 Array is a method which simultaneously and quantitatively detects AFB1,2, G1,2, OTA, DON, ZEA, FBs, T-2/HT-2 Toxins, DAS and PAX in feed and feed products.
The Biochip is a ceramic tile on which antibodies, for each of the mycotoxins, are inter-spaced and spotted on predetermined positions [Discrete Test Regions (DTRs)] on the surface. DTRs enable the accurate identification of the different mycotoxins based on the spatial location of each antibody spot. Randox mycotoxin arrays are capable of accurately detecting all regulated mycotoxins i.e., AFBs, OTA, DON, ZEA, FBs, T-2/HT-2 Toxins, PAX and DAS. In the area of multi-mycotoxin determination in feed, LC-MS/MS is the only other platform capable of simultaneous and quantitative detection. However, this method is expensive in terms of initial capital outlay, analysis, and maintenance costs.
The performance and proficiency of the Myco 9 Array was successfully validated in a third-party laboratory validation programme. This study involved third-party government and private laboratories, where different operators independently analysed 17 samples duplicated across all participating 3rd party laboratories. The Myco 9 Array showed high proficiency with 99% of the results falling within an acceptable Z-score range of -2|<Z<|+2 for all mycotoxins tested. Precision and accuracy range from 100% for DON, and 99% pass for AFs, ZEA, OTA and FBs. T-2 Toxins on the other hand recorded a 97% accuracy. The reproducibility co-efficiency of variation was between 16 – 20% meeting the set criterion of <40% and is, therefore, fit-for-purpose. Using a HorRat approach, the target reproducibility was met for DON, ZEA, T-2/HT-2 Toxins, FBs, OTA and AFB1,2, G1,2, assays. The study demonstrated that the Myco 9 Array results can be reliably reproduced for testing feed samples. There has been a consistent agreement between Myco 9 Array results and those of confirmatory methods for all nine mycotoxins including PAX and DAS. However, in this study samples were negative for the PAX and DAS assays, therefore, reproducibility data could not be computed for these two assays. The consistency of the data shows that the Myco 9 Array for the simultaneous detection of 9 mycotoxins in feed is fit-for-purpose.
Randox Food Diagnostics will be at the World Mycotoxin Forum in Belgium from the 9th – 11th October 2023, visit our booth or contact us to discuss our mycotoxin screening solutions further!
About Dr. Liberty Sibanda
Dr. Liberty Sibanda, having completed his PhD in Pharmaceutical Sciences at Ghent University, has extensive knowledge of the diagnostics industry. An Applications Manager for Randox Food Diagnostics Ltd., Dr. Sibanda has over 20 years of experience developing and marketing mycotoxin test kits and has published numerous papers on the detection of mycotoxins in food and feed.
