Mycotoxins (from Greek mykes = fungus and Latin toxicum = poison) are toxic secondary metabolites produced by filamentous fungi (molds), primarily of the genera Aspergillus, Fusarium, and Penicillium. They contaminate agricultural commodities — cereals, nuts, spices, dried fruits, coffee, and wine — either pre-harvest in the field or post-harvest during storage and processing.
The most significant mycotoxin groups in food safety include:
- Aflatoxins (B1, B2, G1, G2, M1) — produced by Aspergillus flavus and A. parasiticus
- Ochratoxin A (OTA) — produced by Aspergillus and Penicillium species
- Deoxynivalenol (DON / Vomitoxin) — a trichothecene produced by Fusarium species
- Zearalenone (ZEN) — an estrogenic mycotoxin from Fusarium
- Fumonisins (B1, B2) — produced by Fusarium verticillioides, primarily in maize
- T-2 and HT-2 Toxins — trichothecenes from Fusarium, common in oats and wheat
Analytical Methods
- HPLC-MS/MS — High-performance liquid chromatography coupled with tandem mass spectrometry. Reference method for multi-mycotoxin screening, capable of detecting dozens of mycotoxins simultaneously at sub-ppb levels.
- LC-MS/MS — Liquid chromatography with tandem mass spectrometry, used for confirmatory quantitative analysis per EN 17595 and similar standards.
- ELISA — Enzyme-linked immunosorbent assay. Cost-effective screening method for single mycotoxins with results in 2–3 hours. Widely used for aflatoxin B1 and DON.
- Lateral Flow Immunoassays (LFD) — Rapid on-site screening with qualitative or semi-quantitative results in 5–15 minutes. Suitable for incoming goods inspection.
EU Regulatory Framework
Maximum levels for mycotoxins in food are regulated by Commission Regulation (EU) 2023/915, which replaced the former Regulation (EC) No 1881/2006 in May 2023. This was further amended by:
- Regulation (EU) 2024/1022 — updated maximum levels for deoxynivalenol (DON), effective from 1 July 2024
- Regulation (EU) 2024/1038 — introduced maximum levels for T-2 and HT-2 toxins for the first time
Selected maximum levels (Regulation (EU) 2023/915, Annex I):
| Mycotoxin | Matrix | Max. Level |
|---|---|---|
| Aflatoxin B1 | Cereals & cereal products | 2.0 µg/kg |
| Sum of Aflatoxins (B1+B2+G1+G2) | Cereals & cereal products | 4.0 µg/kg |
| Aflatoxin B1 | Almonds, pistachios, apricot kernels | 8.0–12.0 µg/kg |
| Ochratoxin A | Roasted coffee | 3.0 µg/kg |
| Ochratoxin A | Dried vine fruit | 8.0 µg/kg |
| Deoxynivalenol | Bread, pastries, biscuits, cereal snacks | 500 µg/kg |
| Zearalenone | Bread, pastries, biscuits, cereal snacks | 50 µg/kg |
| Fumonisins (B1+B2) | Maize-based foods for direct consumption | 400 µg/kg |
Frequently Asked Questions
What are the most dangerous mycotoxins?
Aflatoxin B1 is classified as a Group 1 carcinogen by the International Agency for Research on Cancer (IARC). It is the most potent naturally occurring liver carcinogen known. Ochratoxin A and fumonisins are classified as Group 2B (possibly carcinogenic to humans).
Can mycotoxins be destroyed by cooking?
Most mycotoxins are thermally stable and are not destroyed by normal cooking, baking, or food processing temperatures. Aflatoxins, for instance, decompose only above approximately 260 °C. Prevention through proper storage conditions (low moisture, controlled temperature) is therefore the primary control strategy.
Which foods are most at risk?
Cereals (wheat, maize, barley, oats), tree nuts, peanuts, dried fruits, spices, coffee, and wine are the food groups most frequently affected. Maize is particularly susceptible to fumonisins, while nuts and dried figs are high-risk for aflatoxin contamination.
How is mycotoxin testing performed?
Accredited laboratories typically use a two-step approach: (1) rapid screening via ELISA or lateral flow devices, followed by (2) confirmatory analysis using LC-MS/MS or HPLC-MS/MS for quantification. Multi-mycotoxin methods can screen for 30+ compounds simultaneously from a single sample extraction.
What does ISO 17025 accreditation mean for mycotoxin testing?
ISO/IEC 17025 is the international standard for testing and calibration laboratory competence. Accredited laboratories must demonstrate technical proficiency, validated analytical methods, measurement uncertainty estimation, and regular participation in proficiency testing schemes. Results from ISO 17025 accredited labs are accepted by regulatory authorities across the EU.