Raising the Bar on Food Contaminant Detection with Chromatography

Analytical scientists are continuing to push chromatographic methods further than current regulations require—screening for more contaminants, in less time, with less waste. Lidija Kenjerić (University of Natural Resources and Life Sciences, Vienna) built an 11-minute ultrahigh-pressure liquid chromatography tandem mass spectrometry (UHPLC–MS/MS) method that quantifies 931 mycotoxins and secondary metabolites in a single injection;¹ Maykel Hernández Mesa and Ana Maria García-Campaña (University of Granada) argue that food-safety testing needs to catch up with how contaminants actually occur, as mixtures rather than single compounds;² and Giorgia Purcaro (University of Liège)³ and a team led by José Bernal (University of Valladolid)⁴ have been closing gaps in how laboratories detect mineral oil hydrocarbons (MOH) in edible oils and other fats. Together, their work points to the same conclusion: chromatography's practical ceiling for simultaneous, high-throughput contaminant detection keeps rising, and regulatory frameworks are still catching up to what the instruments can already do.

Faster Testing, Without Sacrificing Regulatory Rigor

Kenjerić's starting point was a routine method that required two 20.5-min high performance liquid chromatography (HPLC) runs per sample—one in positive ionization mode, one in negative. By moving to UHPLC and using fast polarity switching to combine both modes into a single run, her team cut that to 11 mins while expanding the analyte scope to 931 mycotoxins and other secondary metabolites in cereal-based food. The trade-off, as she explains it, is real: narrower peaks and a very high number of concurrent MRM transitions reduce the dwell time available per compound, which pushed up limits of quantification (LOQs) at low spiking levels compared to the slower method. But those LOQs still met the performance criteria set by SANTE and Eurachem guidelines, meaning the faster method didn't just work as a screening tool, but held up for regulatory-grade quantification.

There's also an environmental case buried in the efficiency gain. Kenjerić's team estimates that replacing the dual-injection workflow with the single 11-min run could cut laboratory CO₂ emissions by roughly 22 tons a year—a reminder that, as she puts it, “substantial environmental benefits can also be achieved through the optimization of established LC–MS/MS methods,” without laboratories needing to invest in entirely new solvents or platforms.

The Case for Treating Contaminants as Mixtures, Not Single Compounds

Hernández Mesa and García-Campaña's work sits inside a broader shift toward exposomics—measuring the totality of chemical exposure rather than one contaminant at a time. Their argument is that current risk assessment, which regulates mycotoxins like aflatoxins and ochratoxin A individually, misses “cocktail effects” where combined toxicity exceeds the sum of individual compounds. That matters more each year: rising temperatures have pushed Aspergillus flavus, the mold behind carcinogenic aflatoxins, out of its traditional subtropical range and into countries like Italy and France, where it's now turning up in maize and, via contaminated feed, in dairy milk. Climate stress is also driving crops to produce “masked mycotoxins”—toxins conjugated to sugars that evade standard testing but can convert back to their toxic form in the human gut.

Building a true multi-mycotoxin “mega-method,” the pair notes, isn't just a matter of scaling up a single LC–MS run. It requires combining targeted and non-targeted approaches, multiple MS platforms, and different separation modes (reversed-phase, hydrophilic interaction liquid chromatography [HILIC], even capillary electrophoresis [CE]) so that no chemical class is missed because of inadequate sample handling. High-resolution MS adds a further advantage because it captures a full-scan “digital map” of the sample, and labs can retrospectively search old data for a newly identified mycotoxin without re-running the sample.

Mineral Oil Hydrocarbons: An Old Contaminant, A Newly Urgent Method Problem

MOH contamination—split into MOSH (saturated hydrocarbons) and MOAH (aromatic hydrocarbons, some structurally close to carcinogenic polycyclic aromatic hydrocarbons [PAHs])—has been a known food-safety issue for years, but interlaboratory testing kept turning up alarmingly inconsistent results. Purcaro's team traced part of the problem to the official saponification method itself: internal standard ratios that should read 1.00 were coming in as high as 1.25 across labs, adding to uncertainty already running up to 60%. Her group's fix—adjusting solvent composition and raising saponification conditions to 120°C for 20 min—brought that ratio down to roughly 1.05 and, notably, uncovered that fatty acid composition itself affects how well internal standards partition during saponification, meaning oils with different fat profiles may need different validation checks.

Bernal et al. tackled the downstream chromatography problem: MOSH and MOAH don't resolve into clean peaks, but “unresolved humps,” and MOSH is frequently indistinguishable from polyolefin oligomeric saturated hydrocarbons (POSH), which are chemically similar hydrocarbons migrating out of plastic packaging. Clean-up steps like epoxidation and alumina fractionation, plus a shift toward comprehensive two-dimensional gas chromatography (GC×GC) for better separation power, are how labs are narrowing that gap, though the group is candid that full harmonization across laboratories hasn't been achieved.

The timing adds urgency: the EU's amendment to Regulation (EU) 2023/915 setting maximum MOAH levels in food cleared committee vote in May 2026, with the legal framework expected to take effect from October 2026 and levels phasing in by food category through 2027–2030, which means that laboratories have a narrowing window to standardize methods that, as both papers show, are still being actively debugged.

What Connects the Three

In each case, researchers found that the constraint wasn't chemistry so much as regulatory infrastructure built for single-compound, single-injection testing. The mycotoxin mega-method and the exposomics framework both argue that food-safety testing needs to catch up with contamination as it actually happens, screening for overlapping mixtures fast enough for routine and emergency use. And in MOH testing, the saponification and chromatography work shows that even where the underlying chemistry has been "settled" for years, quietly unresolved measurement problems can undercut every method built on top of them. Faster, broader-scope methods are arriving well ahead of the regulations meant to govern them, and, as the CO₂ savings estimate suggests, the push for speed is turning out to be a sustainability win as well, even when that wasn't the goal.

References

1. Kenjeric, L.; Sulyok, M.; Bueschl, C.; Malachova, A.; Krska, R. Exploring the Limits of UHPLC–MS/MS with Polarity Switching towards the Quantification of 931 Mycotoxins and Other Secondary Metabolites in Cereal-Based Food. J Food Compos Anal 2026, 151, 108908. DOI: 10.1016/j.jfca.2026.108908
2. Hernández-Mesa, M.; García-Campaña, A. M.; et al. The Role of Analytical Chemistry in Investigating Mycotoxins Within the Exposomics Framework. TrAC Trends Anal Chem 2026, 200, 118857. DOI: 10.1016/j.trac.2026.118857
3. Gorska, A.; Ferrara, D.; Albendea, P.; Cordero, C. E.; Purcaro, G. Update on the Microwave-Assisted Saponification Conditions for Mineral Oil Hydrocarbons Determination in Fats and Oils. Analyst 2025, 150, 5190–5200. DOI: 10.1039/D5AN00701A
4. Jano, A.; Ares, A. M.; Santos Costa, F.; et al. Recent Advances in Sample Preparation for the Determination of Mineral Oil Saturated (MOSH) and Aromatic Hydrocarbons (MOAH) in Food Matrices. Microchem J 2026, 225, 118083. DOI: 10.1016/j.microc.2026.118083