Zearalenol

Zearalenol refers to a group of mycotoxins that are hydrogenated metabolites of zearalenone, produced by Fusarium species that commonly infect cereals and feed grains. The most studied members are alpha-zearalenol and beta-zearalenol, with gamma-zearalenol being less common. These compounds share the core zearalenone structure but differ in the position of hydroxyl groups, which influences their biological activity. In food and feed, zearalenol compounds often occur together with zearalenone.

Zearalenol compounds retain estrogenic activity by binding to estrogen receptors. They can mimic the effects of natural estrogen, potentially disrupting reproductive function in animals and, to a lesser extent, in humans. Alpha-zearalenol generally exhibits greater estrogenic activity than beta-zearalenol, and their potency can vary with species and context. In domestic animals, exposure is associated with signs such as altered estrous cycles, vulvar swelling, and reduced fertility. Sensitivity is particularly notable in swine, but other livestock can be affected as well. Humans are primarily exposed indirectly through contaminated cereal products, though the health significance depends on intake and metabolism.

Occurrence and processing: Zearalenol derivatives are frequently found in cereals and cereal-based foods and feeds affected by Fusarium contamination. Processing and cooking may reduce but not reliably eliminate these compounds. In animals, zearalenones and zearalenols are metabolized in the liver to various conjugates, influencing toxicity and excretion.

Regulation and detection: Food safety agencies monitor zearalenone and related metabolites, including zearalenol, due to their estrogenic potential. Analytical methods such as liquid chromatography–mass spectrometry are used for detection in grains, foods, and feeds. Regulatory limits vary by jurisdiction and matrix, reflecting risk assessments and exposure scenarios.