Arnau Vidal, Marthe De Boevre, Sarah De Saeger
Centre of Excellence in Mycotoxicology and Public Health, Ghent University
Mycotoxins are toxic fungal secondary metabolites, and contaminate agricultural commodities during cultivation, harvesting, transport, processing and storage. Many filamentous moulds are toxigenic with the most important producing genera being Aspergillus, Fusarium and Penicillium (Pitt et al., 2000). Mycotoxins are present in a wide range of products from agricultural crops (rice, wheat, rye, barley, corn, soybeans, sorghum, nuts, spices), cereal-based food (baking products, pasta, breakfast cereals), beverages (fruits, juices and puree, beer and wine), animal feed, to several animal products (dairy products and meat). Regardless of decades of extensive mycotoxin research, mycotoxins are still commonly present in food, and mycotoxins’ exposure remains a challenging problem worldwide, resulting in several diseases in humans due to chronic or even acute exposure.
There are a large number of mycotoxins with a great diversity in their mode of action and also the combined effects of multiple mycotoxins on diseases deserve further investigation. Due to their toxicity level, there is an imperative need to assess human mycotoxin exposure. Some of the exposure assessment have been traditionally performed combining consumption and occurrence data. For this reason, large amounts of mycotoxin analysis in a wide range of food were carried out. However, it is well known that these methods rely on some assumptions and uncertainties, even when probabilistic approaches are used. Therefore, with the aim to evaluate the mycotoxin exposure accurately, analysis of mycotoxins biomarkers has been proposed as a successful method to assess the exposure to exposition of individuals through estimation of their metabolites in biological fluids, normally urine or blood. Biomarker refers to a characteristic that is objectively measured and evaluated as an indicator of normal biological processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention (Atkinson, et al., 2001). Specific well-characterized biomarkers have shown to predict relevant clinical outcomes across a variety of treatments and populations. Thanks to the high sensitivity of the recently developed analytical instruments, different liquid chromatography tandem mass spectrometry methods (LC-MS/MS) for the detection and quantification of mycotoxins in biological fluids have been developed. Thus, several publications analysed mycotoxin biomarkers in biological fluids and they showed an unexpectedly high exposure, even above the upper tolerance level for some individual mycotoxins. For instance, all analysed urine samples (n = 239) had deoxynivalenol presence and 30 % of adults exceeded the tolerable daily intake in Belgium (Heyndrickx et al., 2015) and deoxynivalenol was also highly present in urine from Spanish population with 91 % of population levels over the tolerable daily intake (Vidal et al., 2016). On the other hand, mycotoxin biomarkers have been used to know the impact of mycotoxin exposure on human health and it has been showed that aflatoxins concentrations were significantly higher in stunted children (Fig. 2) compared to non-stunted, as well as in children with severe acute malnutrition compared to controls (McMillan et al., 2018). Although the powerful use of biomarkers, nowadays, there is few existing information about mycotoxin biomarkers and only deoxynivalenol and aflatoxin have validated biomarkers.
Therefore, it is imperative the validation of more mycotoxin biomarkers. To achieve the biomarkers validation 2 step are needed:
To sum up, food have a large presence of mycotoxins and although their toxicity, humans have a high exposure to them. However, nowadays, it does not exist an accurate method to assess mycotoxin exposure in human. For this reason, it is essential to search for accurate ways to assess mycotoxins exposure to know the real impact of mycotoxins on human health.
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