FAQ

Masked mycotoxins are toxic substances in which the toxin is usually bound to a more polar substance such as glucose, sulfate, amino acids,… . They are referred to be masked mycotoxins, as these substances escape established analytical techniques but can release their toxic precursors after hydrolysis.

Masked mycotoxins escape the techniques because of their high polarity. Therefore they are difficult extractable and they will be lost in the clean-up-steps.

Fumonisins are a group of mycotoxin produced mainly by Fusarium verticillioides and F. proliferatum. They can be classified into four groups, A, B, C and P, among which Fumonisin B is the most important group. Fumonisins mainly are found in maize and maize-based food and feed. The contamination usually takes place on the field during the last stages of the growing season and is accelerated by warm and humid climatic condition. These mycotoxins have shown to be the cause of many diseases in animals such as leukoencephalomalcia in horses, pulmonary oedema in swine and cancer in rats and humans.

Molecularly Imprinted Polymers MIPs are polymers exhibiting high selectivity and affinity to a predetermined molecule which serves as a template. Their special properties are obtained through the formation of specific recognition sites in synthetic polymers during a polymerization process. The recognition sites mimic the binding sites of antibodies and other biological receptor molecules. In comparison to biological counterparts, MIPs possess several advantages including storage stability, high mechanical strength, easy preparation and low cost.

Food and feed can be affected by several mycotoxin producing fungal species and different types of mycotoxins can also be produced by one mould resulting in the cooccurrence of different types of mycotoxins. For monitoring food and feed crops multi-mycotoxin methods have been developed.

YES: Breathing-in fungal spores, by humans and by animals, needs to be prevented as much as possible since this can cause infections of the respiratory tract. Moreover, the most frequent mould species in silages is Penicillium roqueforti, which has a blue-greenish color. This mould species can produce mycotoxins under certain conditions, comprising a risk for animal health.

The Sick Building Syndrome describes a poorly defined set of non-specific symptoms (headache, irritation, depression, dermatitis, allergy) attributed to the occupancy of a building with poor indoor air quality, mostly associated with mould growth.
In water-damaged interiors some moulds may produce secondary metabolites – mycotoxins – that can affect organisms by a variety of mechanisms. Mycotoxins are not volatile, thus they present in indoor environments on airborne fungal particles and spores. Mycotoxins can cause a danger for human health mostly by inhalation. Few of mycotoxins occurring in indoor environments suppose to be carcinogenic (e.g. aflatoxins, ochratoxin A, sterigmatocystin), other ones may cause immune system damage, different kinds of irritation.

These are simple rapid tests used to determine mycotoxin contamination above or below a cut-off value. The cut-off value is often specified by the manufacturer.

Ergot alkaloids are metabolites produced by fungi of the Claviceps genus which grows on rye, barley, wheat and other cereals. The incidence of ergot alkaloids depends on the kind of cereal, the genus of the fungi geographical and climatological circumstances. These alkaloids can cause ergotism in humans and mammals upon consumption of contaminated food or feed. Ergotism is a common name for a variety of convulsive and gangrenous symptoms which can even provoke death.

Six ergot alkaloids are mentioned in an EFSA opinion (EFSA, 2005) as being the most relevant ones regarding presence and toxicity. These alkaloids are ergotamine, ergocristine, ergosine, ergocryptine, ergometrine and ergcornine.

Mycotoxins in animal feed may cause a possible risk to animal health and animal performance. In this way they influence negatively the production results. The symptoms of an excessive intake of mycotoxins in poultry depends on the type of mycotoxin ingested. For example, chickens are highly sensitive to aflatoxins, while they are much more resistant to deoxynivalenol. In case of aflatoxicose, mainly diarrhea, anemia and convulsions are observed. Deoxynivalenol causes vomiting, a decrease in food intake and intestinal damage. An intoxication with the mycotoxin T-2 is characterized by necrosis of the beak, in addition, it also causes intestinal damage and a lower fecundity. Chickens are less sensitive to zearalenone and ergot alkaloids. A combination of different mycotoxines can lead to enhanced or reduced effects.

In northern temperate regions, the Fusarium mycotoxin DON is one of the most frequent contaminants of maize and small grain cereals. This contamination of cereal crops is seen under low temperature and high humidity conditions. If critical concentrations of DON in diets for farm animals are exceeded, the health, growth and reproductive performance of animals can be impaired. The toxic effects of DON are well documented and among farm animals, the pig seems to be particularly sensitive to the dietary intake of DON. DON has been associated with symptoms varying from partial feed refusal and decreased feed intake at feed concentrations as low as 1-2 mg/kg feed, to vomiting and complete feed refusal at concentrations more than 20 mg/kg feed. Substantial economic losses have therefore been attributed to DON contamination of pig feed.

Fungi produced mycotoxins are very stable secondary metabolites that often end up in the food and feed chain. Of all monogastric animals, pigs seem to be one of the most sensitive species to mycotoxins, due to their high feed intake per kilogram of body weight and their maize-rich diet. Until now, more than 200 different mycotoxins have been identified, but only a few have been shown to affect health and swine performance. These include deoxynivalenol (DON), T-2 toxin, fumonisins, zearalenone (ZEA), aflatoxins, ochratoxins (OT) and ergot alkaloids.
The effects of moderate to high amounts of mycotoxins in pigs have been well characterized. The effects of trichothecenes (DON and T-2 toxin) range from a reduced feed intake and vomiting to complete feed refusal. Consumption of fumonisins can cause porcine pulmonary oedema (PPE) and liver damage and zearalenone has been shown to cause fertility impairments. Aflatoxins act as immunosuppressants and reduce overall pig health. Ochratoxins, especially ochratoxin A (OTA), are common contaminates of barley and cause a reduced growth rate, liver and kidney damage en an increased mortality. Finally, ergot alkaloids cause a broad range of symptoms, varying from reduced growth and vomiting to reduced lactation and abortion.
Although the interest in the effects of low mycotoxin concentrations, which are more relevant in practice, is increasing, the influence is not well known.

There is not always a clear relationship between mycotoxin content and the Fusarium species present. Although there is a positive association between Fusarium Head blight and mycotoxin content in harvested grain, low levels (or absence) of visual symptoms do not necessary result into low levels of mycotoxins. On the other hand fields infected by Microdocium nivale will contain no mycotoxins because this species does not produce mycotoxins.

The main Fusarium species in Flanders that are able to produce mycotoxins are Fusarium graminearum (deoxynivalenol, zearalenone, fusarin C and nivalenol), Fusarium moniliforme (fumonisins, fusarin C, moniliformin), Fusarium poae (T2-toxin, 15-deacetylneosolanil), Fusarium culmorum (culmorine, moniliformin, zearalenone, deoxynivalenol, furasin C, nivalenol) and Fusarium avenaceum (zearalenone, nivalenol, fusarin C, moniliformine).

Weather conditions account for most the most variation in mycotoxin content. High relative humidity and rainfall during flowering period results in elevated mycotoxin accumulation. Wheat variety accounts for the most variability in mycotoxins amongst agronomic variables, there is a wide range of wheat varieties ranging from very susceptible to highly resistant for mycotoxin accumulation. Mycotoxin content is also affected by the previous crop, when wheat follows maize, wheat samples contain more mycotoxins, because Fusarium species are able to survive saprophytically on maize residues and lead to infection of wheat growing on that field the next season. Soil cultivation is a another important factor, no-tillage results in less removal of crop debris, and infected plant material maintained on the soil surface can lead to infection.

Trichothecenes are a very large family of chemically related mycotoxins, for example deoxynivalenol (DON) and T-2 toxin. The gross toxic effects of trichothecenes on animals include growth retardation, protein inhibition and inhibition of protein synthesis . Trichothecenes lead to feed refusal and vomiting, therefore DON is also known as vomitoxin. Trichothecenes also have an effect on poultry production, a decrease in egg production and cause thinning of egg shells. It is generally regarded that the presence of oral lesions in poultry is the primary means of diagnosing tricothecene toxicoses in the field. Mycotoxins alter reproductivity. Pigs refuse food intake and they have a negative effect on the immune system and lacting cows show a significant reduce in milk production.

MIPs have applications in several domains, but the most frequent one is the implementation of MIPs in the clean-up of samples. The analysis of mycotoxins in complex matrices, like food and feed, requires a very selective and sensitive detection. Because of this it is necessary to carry out a clean-up step before analysing the samples. The efficiency of this step affects the lowest detectable concentration of mycotoxins. Matrix interferences (matrix compounds influencing the detection of mycotoxins) can be removed during analysis by using selective MIPs, enabling us to quantify very low amounts of mycotoxins.

Fungi produced mycotoxins are very stable secondary metabolites that often end up in the food and feed chain. Of all monogastric animals, pigs seem to be one of the most sensitive species to mycotoxins, due to their high feed intake per kilogram of body weight and their maize-rich diet. Until now, more than 200 different mycotoxins have been identified, but only a few have been shown to affect health and swine performance. These include deoxynivalenol (DON), T-2 toxin, fumonisins, zearalenone (ZEA), aflatoxins, ochratoxins (OT) and ergot alkaloids.
The effects of moderate to high amounts of mycotoxins in pigs have been well characterized. The effects of trichothecenes (DON and T-2 toxin) range from a reduced feed intake and vomiting to complete feed refusal. Consumption of fumonisins can cause porcine pulmonary oedema (PPE) and liver damage and zearalenone has been shown to cause fertility impairments. Aflatoxins act as immunosuppressants and reduce overall pig health. Ochratoxins, especially ochratoxin A (OTA), are common contaminates of barley and cause a reduced growth rate, liver and kidney damage en an increased mortality. Finally, ergot alkaloids cause a broad range of symptoms, varying from reduced growth and vomiting to reduced lactation and abortion.
Although the interest in the effects of low mycotoxin concentrations, which are more relevant in practice, is increasing, the influence is not well known.

Contamination of feed with mycotoxins is very common. Suppression of moulds and toxin production is mainly obtained by respecting good agriculture practices. At unfavourable climatological circumstances and/or when preventive measures against moulds and mycotoxins have however failed, a variety of physical, chemical and biological methods can be used for decontamination of mycotoxins from contaminated feeds. The use of mycotoxin adsorbents as feed additives can be valuable to reduce the risk for mycotoxicoses in farm animals. Mycotoxin binders or adsorbents are substances that bind to mycotoxins and prevent them from being absorbed through the gut and into the blood circulation. There can be made a distinction between anorganic binders like for example activated carbon and organic binders like yeast cell walls.

Antibodies are proteins produced by the B-lymphocytes of the immune system in response to foreign molecules, called antigens. An antibody produced by a single clone of cells (specifically, a single clone of hybridoma cells) and therefore a single pure homogeneous type of antibody, is called a “monoclonal” antibody.

An immunoassay is a specific type of biochemical test that measures the presence or concentration of a substance. The analyte undergoes an immune reaction with a second substance, which is used to determine the presence and amount of the analyte. This type of reaction involves the binding of one type of molecule, the antigen, with a second type, the antibody. The analyte may be either the antigen or the antibody.

Biomarkers or biological markers are present in human and change on a defined way by exposure to toxins. These biomarkers of exposure can include the excreted toxin, its metabolites or products of interaction between the toxin and macromolecules such as DNA. They can be analyzed in different matrices, commonly blood and urine. Biological markers must be measured accurately and changes must be significant for a specific exposure. The choice of biomarker will depend for instance on the availability of tissue or body fluid, the method, specificity and sensitivity.

Mycotoxins are one of the most important chronic risk factors in our food chain, therefore it is important to estimate the exposure of the population to these toxins. Currently, the assessment of mycotoxin exposure is based on the occurrence in food and questionnaire data on food consumption. This indirect approach is not reliable due to the inaccuracy of food consumption data, the heterogeneous distribution in food, the exposure through inhalation and the presence of masked mycotoxins. A more accurate assessment of the exposure at the individual level can be performed by direct measurement of biomarkers of exposure, because the individual variation in absorption, distribution, metabolisation and excretion is integrated into the formation of the biomarker.