Introduction to Amanitin Detection

Mushroom foraging is a popular activity worldwide, but distinguishing between edible and toxic species remains a significant challenge. Poisonous mushrooms, particularly those containing amanitin toxins, are responsible for over 100 deaths annually and require urgent medical intervention for thousands of people. Researchers from the Agricultural Research Service (ARS) have developed a highly sensitive and reliable field test for detecting amanitin in mushrooms and biological samples.

This immunoassay-based test provides a rapid, portable, and effective method to identify the presence of deadly toxins in both mushrooms and urine samples, offering valuable applications in medical diagnostics, veterinary care, and food safety.

High Sensitivity and Rapid Detection

The new test can detect as little as 10 parts per billion of amanitin in a 10-minute analysis from a rice grain-sized mushroom sample. Additionally, the test can identify amatoxin poisoning in human and dog urine, which is critical for early medical intervention.

"We developed the test primarily for mushrooms as food products. Serendipitously, it was sensitive enough to also detect the toxin in urine," said Candace Bever, an ARS microbiologist from the Foodborne Toxin Detection and Prevention Research Unit in Albany, California.

Addressing a Critical Gap in Poisoning Diagnosis

Currently, no definitive point-of-care diagnostic test exists for amanitin poisoning. Diagnosing amatoxin ingestion is challenging, often requiring the elimination of other gastrointestinal conditions before treatment can begin. This test offers a direct and early detection method, improving diagnostic speed and potentially enhancing patient survival rates.

"Our hope is that doctors and veterinarians will be able to quickly and confidently identify amatoxin poisoning rather than having to clinically eliminate other suspected gastrointestinal diseases first," Bever explained. "We also hope that will give patients a better chance at recovery, even though there are no clearly effective, specific treatments right now."

Enhancing Safety for Mushroom Foragers

Foraging for wild mushrooms is widely practiced in regions including Europe, Australia, Japan, Korea, the Middle East, and North America. However, differentiating between toxic and non-toxic mushrooms relies on visual identification and field guides, which may not always be reliable.

• Deadly mushrooms closely resemble edible varieties, making misidentification a frequent cause of poisoning. For example:
  • The Springtime Amanita (Amanita velosa) is a desirable edible species.
  • The Death Cap (Amanita phalloides), responsible for over 90% of fungus-related poisoning deaths in Europe, closely resembles it.

This test provides a chemical-based verification method, adding an extra layer of safety for foragers. If commercialized, it could help prevent poisoning incidents and make wild mushroom consumption safer.

"This test can provide more information about a wild mushroom beyond physical appearance and characteristics, and detect something we cannot even see—the presence of amanitins," said Bever.

Limitations of the Test

While the test is the most sensitive and reliable method available for amanitin detection, it has specific limitations:

• It only detects amanitin toxins and does not screen for hallucinogens or other toxic compounds.
• It cannot determine if a mushroom is edible—it merely confirms the presence or absence of amanitins.

Future Applications and Commercial Potential

The test has significant potential for:

• Medical diagnostics: Rapid detection in suspected poisoning cases.
• Veterinary use: Identifying poisoning in animals, particularly dogs.
• Food safety: Screening wild-harvested mushrooms before consumption.
• Consumer foraging safety: A commercial test kit could provide a reliable tool for mushroom enthusiasts.

If a commercial partner is identified, this test could become a widely available field tool to prevent poisoning incidents and save lives.

Scientific Foundation and Collaborators

The test is based on an immunoassay using a monoclonal antibody—a lab-produced protein that specifically binds to amanitin toxins. This approach ensures high accuracy and specificity in toxin detection. The research team included scientists from the University of California-Davis, the Pet Emergency and Specialty Center of Marin, and the Centers for Disease Control and Prevention (CDC).

Conclusion

The newly developed portable amanitin detection test represents a major advancement in food safety, toxicology, and forensic science. By providing rapid and accurate toxin identification, it addresses a critical need in mushroom foraging, medical diagnostics, and veterinary care. With further development and commercialization, this test could become an indispensable safety tool for foragers, healthcare professionals, and researchers worldwide.