How Nuclear Technology is Revolutionizing the Detection of Toxins in Pistachios
Pistachios, a nut once reserved exclusively for royalty, like the legendary Queen of Sheba, are now a beloved snack enjoyed worldwide. With global production exceeding one million tonnes in 2022 from major producers such as Iran, the United States, and Turkey, pistachios have become a staple in many diets. However, this popularity comes with the challenge of contamination by aflatoxins—deadly, carcinogenic toxins produced by certain moulds and fungi.
The Hidden Danger of Aflatoxins
Aflatoxins were first discovered in 1960 after an incident in the UK where thousands of turkeys died from consuming contaminated feed. These chemical compounds are primarily produced by moulds that infect crops like maize and nuts, including pistachios. Aflatoxins are highly toxic and have been linked to severe health issues such as liver failure, tumours, and even sudden fatal poisoning in cases of high exposure.
Pistachios naturally develop a hard shell that protects against external contamination. However, as the pistachio ripens, this shell splits open, making the nut vulnerable to moulds and insects—key contributors to aflatoxin contamination. The toxins are invisible to the naked eye, but mould can sometimes be observed in the form of black or grey spots on pistachio hulls or kernels. Improper storage conditions after harvest can exacerbate contamination levels. Because of their danger, international safety regulations strictly limit aflatoxin levels in pistachios to no more than 10 micrograms per kilogram, roughly equivalent to a grain of sugar in a 100 kg sack.
Conventional Testing—Challenges and Limitations
Detecting aflatoxins with conventional laboratory techniques remains time-consuming, expensive, and reliant on specialized equipment and trained personnel. This complexity limits the ability to conduct rapid, on-site testing, especially in resource-poor regions or during emergencies when swift action is critical to prevent the distribution of contaminated food.
A Breakthrough: Nuclear Technology-Based Aflatoxin Detection
The International Atomic Energy Agency (IAEA) has developed an innovative nuclear technology-based detection method that promises to transform how aflatoxins in pistachios are identified. Since 2023, this nuclear technique has been implemented by an increasing number of countries, offering a faster, cheaper, and more accessible alternative to traditional testing.
At the FAO/IAEA Food Safety and Control Laboratory (FSCL) in Seibersdorf, Austria, experts devised a "lab in a box" solution. This approach uses ceramic electrical conductors printed with carbon-based ink, embedded with specialized sensors capable of detecting four types of aflatoxins at concentrations 150 times lower than the permissible limit. When a sensor is connected to a device called a Potentiostat, it emits a small electrical signal indicating the presence of aflatoxins. Remarkably, the results can be recorded and interpreted using a simple mobile phone, allowing for field deployment and immediate risk assessment.
Head of FSCL, Christina Vlachou, highlighted the significance of this advancement: "It’s faster, cheaper and doesn’t require an entire lab. That means it can be used in the field, even during emergencies, and in countries that need it most."
Beyond Pistachios: Addressing Food Safety Challenges Worldwide
Climate change intensifies threats to food safety by promoting the spread of toxins like aflatoxins and contamination by heavy metals. This expands the need for reliable, portable testing tools to secure food supplies, especially in vulnerable regions facing food insecurity.
Under the IAEA’s Atoms4Food initiative, in partnership with the Food and Agriculture Organization (FAO), further research and development focus on extending nuclear and complementary technologies to detect a broader range of contaminants in various food products. The FSCL has already adapted the sensor technology for detecting fumonisins—a harmful mycotoxin associated with cancer and birth defects—in maize, as well as toxic metals such as lead in fruit juices.
Such flexible, scalable detection tools are critical to supporting food safety emergency responses and ensuring public health in the face of growing global food system complexities.
Looking Forward
The IAEA’s pioneering work in using nuclear technology offers a powerful solution to a long-standing problem in agricultural food safety. By enabling rapid, accurate, and affordable testing of aflatoxins and other contaminants, these innovations protect consumers and support food security worldwide. As Christina Vlachou notes, "The IAEA is creating resilient and robust interventions to assist food safety stakeholders in countries around the world, maintaining safety and hygiene at required levels to avoid foodborne illnesses."
This breakthrough underscores the potential of nuclear science beyond energy and medicine, demonstrating its vital role in safeguarding the global food supply for generations to come.
For more information on the IAEA’s work and to receive weekly updates, visit the IAEA website.
