In an era where health-conscious consumers are meticulously tracking macronutrients, monitoring daily caloric intake, and prioritizing "whole" foods like fresh fruits, vegetables, and lean proteins, a silent concern persists beneath the surface. While the nutritional value of our diet is paramount, the chemical safety of the food on our plates remains a complex, often invisible, challenge. Even the most wholesome ingredients can harbor contaminants—some derived from environmental exposure and others born from the very act of cooking.
Among these hidden threats are polycyclic aromatic hydrocarbons (PAHs), a group of hydrophobic organic compounds characterized by their multiple fused aromatic rings. Linked to potential carcinogenic effects, PAHs have become a primary focus for food safety regulators worldwide. Recent advancements in analytical chemistry, led by researchers at Seoul National University of Science and Technology (SeoulTech), are now providing a more efficient, sustainable, and precise way to detect these substances, marking a significant step forward in protecting public health.
The Chemistry of Contamination: Why PAHs Matter
PAHs are not intentionally added to food; they are unintended byproducts of incomplete combustion. According to the National Cancer Institute (NCI), these compounds frequently manifest during high-heat cooking techniques. When fats and juices from meat drip onto hot surfaces or open flames, they generate smoke laden with PAHs, which then deposit onto the surface of the food. Furthermore, processes such as smoking, grilling, roasting, and frying act as catalysts for the formation of these rings.
The public health concern stems from animal studies showing that certain PAHs are associated with increased cancer risk. While human population studies have yet to establish a definitive, direct link between the consumption of charred, home-cooked meats and cancer in humans, the uncertainty underscores the critical need for rigorous monitoring. By accurately identifying where and how these contaminants accumulate, scientists, food manufacturers, and regulatory bodies can develop strategies to mitigate exposure.
A Legacy of Labor: The Shift Away from Conventional Extraction
For years, the detection of PAHs in complex food matrices—ranging from oils and meats to grains—was a laborious and resource-heavy endeavor. Conventional extraction techniques, such as solid-phase extraction (SPE), liquid-liquid extraction, and accelerated solvent extraction, have long served as the industry standard. While effective in their own right, these methods are notorious for being time-consuming, requiring significant manual labor, and relying on large volumes of organic solvents.
For the modern laboratory, these traditional methods present a double burden: they are economically inefficient and environmentally hazardous. The reliance on chemical-intensive procedures creates unnecessary waste and poses potential health risks to laboratory staff. Consequently, the food science community has been aggressively seeking a "greener," more streamlined alternative.
The QuEChERS Revolution: A New Analytical Paradigm
Enter QuEChERS—an acronym standing for "Quick, Easy, Cheap, Effective, Rugged, and Safe." Originally developed to detect pesticide residues, this methodology has been adapted by food scientists to revolutionize how we measure contaminants like PAHs.
In a landmark 2025 study published in Food Science and Biotechnology, a team led by Professor Joon-Goo Lee at the Seoul National University of Science and Technology demonstrated the potency of the QuEChERS approach. The researchers sought to measure eight specific PAHs: Benzo[a]anthracene, Chrysene, Benzo[b]fluoranthene, Benzo[k]fluoranthene, Benzo[a]pyrene, Indeno[1,2,3-cd]pyrene, Dibenz[a,h]anthracene, and Benzo[g,h,i]perylene.
Chronology of the Research
The team’s workflow involved several critical stages:
- Extraction: Utilizing acetonitrile to pull the target PAHs from the food matrices.
- Purification: Testing various combinations of sorbents to isolate the contaminants from the complex background of fats, proteins, and carbohydrates.
- Validation: Applying the refined method across a wide variety of food samples to ensure consistent performance.
- Quantification: Using gas chromatography and mass spectrometry (GC-MS) to provide high-resolution data on the concentration of the compounds.
Supporting Data: Accuracy in the Face of Complexity
The findings from the SeoulTech study provide compelling evidence for the reliability of the QuEChERS-based method. The team achieved calibration curves for all eight PAHs with R² values exceeding 0.99, confirming a highly linear and stable measurement system.
When analyzed via gas chromatography and mass spectrometry, the limits of detection (LOD) were remarkably low, ranging from 0.006 to 0.035 µg/kg. Similarly, the limits of quantification (LOQ) spanned 0.019 to 0.133 µg/kg. These figures are vital for regulatory compliance, as they allow for the detection of even trace amounts of PAHs.
Recovery rates were equally impressive. At a concentration of 5 µg/kg, recoveries ranged from 86.3% to 109.6%; at 10 µg/kg, from 87.7% to 100.1%; and at 20 µg/kg, from 89.6% to 102.9%. Furthermore, precision values—a measure of the consistency of the results—remained between 0.4% and 6.9% across all tested food categories. Perhaps most revealing was the team’s analysis of common consumer goods: the highest PAH levels were identified in soybean oil, followed closely by duck meat and canola oil.
Broadening the Horizon: Recent Developments in 2025
The momentum behind QuEChERS has continued to build throughout 2025. A separate study published in the journal Foods utilized a modified QuEChERS method incorporating a "freeze-out" step to test 302 retail food samples. This research identified Kezuribushi (a traditional Japanese smoked and dried fish product) as having the highest concentrations of four priority PAHs. The researchers also flagged grilled chicken feet as a potential health concern, applying the European Food Safety Authority (EFSA) "Margin of Exposure" approach to assess risk.
Simultaneously, research published in Journal of Food Composition and Analysis applied a modified QuEChERS method using Z-Sep (a zirconia-based sorbent) to clean up cereal samples. By testing 96 cereal products from the Romanian market, researchers found that while chrysene was present in 17% of raw cereal samples, it was notably absent in derived products, offering a rare bit of positive news for the processed food industry.
Official Perspectives: The Vision of Prof. Joon-Goo Lee
Professor Joon-Goo Lee, the lead researcher at SeoulTech, emphasizes that the transition to these streamlined methods is as much about environmental stewardship as it is about food safety.
"This method not only simplifies the analytical process but also demonstrates high efficiency in detection compared to conventional methods," Prof. Lee states. "It can be applied to a wide range of food matrices, and our research can improve public health by providing safer food, while simultaneously reducing the use and emission of hazardous chemicals in laboratory settings."
Prof. Lee’s background makes him uniquely qualified to advocate for these changes. With a resume that includes serving as a scientific officer at Korea’s Ministry of Food and Drug Safety, a visiting researcher at Food Standards Australia New Zealand (FSANZ), and an expert for the FAO/WHO Joint Expert Committee on Food Additives (JECFA), his work is rooted in both academic rigor and real-world regulatory necessity.
Implications for the Global Food Industry
The implications of these advancements are profound. For the food industry, the adoption of faster, cheaper, and more precise testing methods means that safety management can become proactive rather than reactive. Companies can now perform routine checks on raw materials and finished products with greater frequency and lower costs, ensuring that contaminated batches are identified before they reach the consumer’s kitchen.
Furthermore, the "rugged" nature of QuEChERS—its ability to handle diverse and complex food types—means that small and medium-sized laboratories can now perform testing that was once reserved for only the most well-funded, high-tech facilities. This decentralization of testing capability could lead to a more robust global safety net.
Conclusion: A Cleaner Path Forward
As the global food supply chain grows increasingly complex, the tools we use to monitor it must evolve. The transition to QuEChERS-based methods for PAH detection represents a critical shift toward a more sustainable and effective food safety regime. By reducing the reliance on toxic solvents, shortening preparation times, and providing higher levels of analytical precision, researchers like Professor Lee are helping to create a future where the health of the consumer is not at odds with the efficiency of the laboratory.
While the risk of PAH exposure from high-heat cooking remains a reality, the ability to accurately quantify these risks provides the transparency necessary to make informed choices. As these methods become more widely adopted across global markets, we can look forward to a food landscape that is not only more nutritious but, crucially, more transparent and safer than ever before.
