Zearalenone: An estrogenic mycotoxin found in grains

Zearalenone (ZEN)

What is Zearalenone?

Zearalenone (ZEN) is a mycotoxin produced primarily by molds of the genus Fusarium, particularly Fusarium graminearum and Fusarium culmorum. These molds mainly infect grains in the field and thrive in humid weather.

Chemically, zearalenone belongs to the resorcylic acid lactones. Although it is not a steroid hormone, it has a pronounced estrogenic effect because its structure resembles that of the human hormone estrogen and it can bind to estrogen receptors.


Where is zearalenone found?

Zearalenone is primarily detected in grains and foods made from them, particularly in:

  • Corn
  • Wheat
  • Barley
  • Oats
  • Rye
  • Flour and baked goods
  • Breakfast cereals
  • Animal feed

The formation of ZEN is favored by humid and temperate weather conditions during the growing and harvesting seasons. As a result, the mycotoxin is regularly detected in grains and grain products in Germany as well.


Health Risks Associated with Zearalenone

Zearalenone primarily affects the endocrine system and can have health effects in both humans and animals.

Acute Toxicity

  • Hormonal changes
  • Menstrual disorders
  • Breast tenderness
  • Temporary impairment of fertility

Chronic Toxicity

  • Hormonal imbalance
  • Impaired reproductive capacity
  • Developmental abnormalities of the reproductive organs
  • Possible effects on pregnancy and fertility
  • Children and pregnant women are particularly sensitive

Based on current scientific knowledge, zearalenone is not considered carcinogenic. However, due to its hormone-like effects, the European Food Safety Authority (EFSA) has established a tolerable daily intake (TDI) to protect consumers from the health risks associated with long-term exposure.