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Mycotoxicoses

Q: What target organs are primarily affected in acute and chronic aflatoxicosis?

In aflatoxin poisoning, the following lesions are noted: Liver — aflatoxins exhibit marked hepatotropism; consumption of products with aflatoxin is described as causing severe poisoning with necrotic liver damage.Kidneys — necrotic kidney damage is described.Digestive tract — hemorrhagic inflammation of the digestive tract is described; aflatoxins also possess a carcinogenic effect and cause GI tumors.

For medical students2 min readUpdated 2026-10-10

Mycotoxicoses are severe foodborne intoxications in humans and animals resulting from the ingestion of food or feed contaminated with mycotoxins. Unlike infectious diseases, the pathology is caused not by the pathogen itself, but by the secondary metabolites of microscopic fungi, which are extremely difficult to detect and destroy in food products.

ProducersPhytopathogenic and saprophytic soil microscopic fungi

Hidden threatToxins can accumulate and persist in products without visible mold growth

ThermostabilityHigh temperatures are incapable of inactivating and destroying mycotoxins

Transmission routesDirect (via plants) and indirect (via animal-derived products)

Etiology and Toxin Accumulation Conditions

The main etiological factor in the development of mycotoxicoses is mycotoxins (which include, for example, aflatoxins). These are specific secondary metabolites that are products of the normal vital activity of phytopathogenic and saprophytic soil fungi.

Directly related to the growth of fungal colonies on various food raw materials and agricultural products, the accumulation process of these hazardous substances is driven by agricultural errors:

Gross violations of crop harvesting agrotechnics.
Improper storage of agricultural crops in unsuitable conditions.
Errors during the processing and transportation stages of food raw materials.

Epidemiology and Transmission Routes

Infection of the organism and subsequent development of intoxication can occur via two main routes, making the control of mycotoxin spread an extremely challenging task in preventive medicine and veterinary science.

Direct route. Occurs through the direct consumption of plant products contaminated with fungi and their metabolites.
Indirect route. Realized through animal-derived products. If farm animals are fed with feed contaminated with mycotoxins, the poisons are metabolized and accumulate in their tissues. Consequently, humans develop intoxication by consuming meat, milk, or eggs from such animals.

> Important epidemiological rule: The presence of mycotoxins in feed or a food product does not necessarily coincide with visible mold growth. The product may look completely wholesome yet contain a lethal dose of fungal secondary metabolites.

Seasonality and Mycotoxin Resistance

Animal mycotoxicoses exhibit a distinct seasonality, which is important to consider during anamnesis collection and epidemiological assessment. Mass poisonings are most frequently recorded in autumn when animals graze on stubble, or in early spring when they consume grass that has survived frosts.

Properties of Mycotoxins (Resistance Factors): A distinctive feature of mycotoxins is their unprecedentedly high resistance to aggressive environmental factors. They demonstrate resistance to:

Freezing (low temperatures preserve rather than destroy the poison).
High temperatures (marked thermostability renders classic heat treatment of food ineffective).
Ultraviolet irradiation.
Ionizing radiation.

Mnemonic

To remember the environmental factors to which mycotoxins are resistant, use the acronym FULT (Freezing, UV, Low/High... wait, let's keep the clinical logic matching the Russian equivalent): I-Z-U-T (Ionizing radiation, Zaprivanie/Freezing, Ultraviolet, Thermostability).

Frequently asked questions

Which specific genera of microscopic fungi are the primary causative agents of human mycotoxicoses?

The primary causative agents of human mycotoxicoses are microscopic fungi of the genera Fusarium, Penicillium, Aspergillus, and Claviceps.

Genus Fusarium — develop on plants, causing fusariotoxicoses.
Genus Penicillium — develop on vegetative or harvested plants, producing dangerous toxins.
Genus Aspergillus — parasitize cereal crops and peanuts, producing aflatoxins.
Genus Claviceps (specifically Claviceps purpurea) — infects cereals (rye), forms sclerotia, and causes ergotism.

What classes of mycotoxins, besides aflatoxins, hold the greatest medical significance?

In addition to aflatoxins, the following widespread and toxic mycotoxins are noted:

Ochratoxins: ochratoxins A, B, C; ochratoxin A is listed among the most widespread and toxic representatives.
Ergot alkaloids: ergotoxin, ergotamine, ergometrine; producer is Claviceps purpurea.
Trichothecenes: a group including about 100 types of toxins, such as deoxynivalenol; produced by Fusarium and other genera.
Other specified mycotoxins: zearalenone, patulin, sterigmatocystin, fumonisins, moniliformin, fusarochromanone, aurofusarin.

What target organs are primarily affected in acute and chronic aflatoxicosis?

In aflatoxin poisoning, the following lesions are noted:

Liver — aflatoxins exhibit marked hepatotropism; consumption of products with aflatoxin is described as causing severe poisoning with necrotic liver damage.
Kidneys — necrotic kidney damage is described.
Digestive tract — hemorrhagic inflammation of the digestive tract is described; aflatoxins also possess a carcinogenic effect and cause GI tumors.

What nosological forms are classified as classic human mycotoxicoses?

The main nosological forms of classic human mycotoxicoses include:

Ergotism — manifests in convulsive, gangrenous, or mixed forms.
Fusariotoxicoses — include alimentary-toxic aleukia (septic angina), sporotrichiellotoxicosis, fusarium graminearum toxicosis, and fusarium nivalenol toxicosis.
"Drunken bread" poisoning — occurs from consuming grain infected with Aspergillus flavus or Fusarium sporotrichiella.
Aflatoxicoses — severe food poisonings caused by Aspergillus toxins.

What laboratory diagnostic methods are used to detect and quantify mycotoxins in food products?

To detect and identify mycotoxins in food products, the following are used:

Physicochemical methods — chromatography and spectrophotometry.
Immunological methods — enzyme-linked immunosorbent assay (ELISA) and radioimmunoassay (RIA).
Biological methods (bioassays) — use of chicken embryos, cell cultures, laboratory animals (rats, mice, guinea pigs), birds (ducklings, pigeons), and sensitive microorganisms.

Testing is preceded by the extraction of the mycotoxin from the sample using an organic solvent.

Can mycotoxins be eliminated by thoroughly boiling the food product?

No. Mycotoxins possess high thermostability and retain their toxic properties even after prolonged exposure to high temperatures.

If animal feed shows no traces of mold, does that mean it is safe?

Absolutely not. A crucial characteristic of mycotoxicoses is that toxins can be present in raw materials and feed even without any fungal mycelium growth visible to the naked eye.

How can a human become infected via the indirect route?

A human becomes infected by consuming meat, milk, or eggs obtained from animals whose diet included feed contaminated with mycotoxins.

Go deeper

Mechanisms of secondary metabolite synthesis by saprophytic and phytopathogenic fungi
Specific effects of aflatoxins on human and animal organisms
Veterinary and sanitary inspection of meat and milk for the presence of mycotoxins
Impact of agricultural technique violations on the epidemiology of food intoxications