RAFA 2024 Highlights: Contemporary Food Contamination Analysis Using Chromatography

Stefan Van Leuwen kicked of the session on food analysis contamination at RAFA 2024. Image Credit: © Permission from RAFA 2024.

The session on food contamination analysis started with a talk from Stefan Van Leeuwen from Wageningen Food Safety Research (WFSR), The Netherlands, entitled: “The Knowns and Unknowns: The Analytical Toolbox to Tackle the PFAS Challenge." Van Leeuwen highlighted the critical need to address the problem of per- and polyfluoroalkyl substances (PFAS) contamination. These molecules possess a significant health risk because of their persistence in the environment and can be detected in a variety of foods. His presentation described an advanced analytical toolkit developed at WFSR and focused on three main approaches: mass balance analysis to determine the total PFAS content, ultra-sensitive targeted detection for specific PFAS at low levels, and the identification of previously unknown PFAS compounds. Van Leeuwen highlighted that high-resolution mass spectrometry using an orbital ion trap mass spectrometer applied to freshwater fish samples revealed that over half of the organic fluorine content could not be attributed to known PFAS, indicating unidentified compounds. This toolkit included sophisticated data acquisition and filtering tools to provide a comprehensive framework for analyzing PFAS in food matrices to help address future analytical challenges in PFAS research, according to Van Leuwen.

Cassandra Jeanot from ONIRIS, France, followed this talk with a presentation entitled: "Simultaneous Activation of Three Levers to Extend the Spectrum of PFAS Studied in Food Matrices." Dervilly described a novel approach to broaden PFAS detection in food, focusing on chronic exposure from food sources such as eggs and fish. By optimizing sample preparation (QuEChERS), data acquisition (liquid chromatography–high-resolution mass spectrometry [LC–HRMS]), and processing, the team advanced a non-targeted screening method for detecting lesser-known PFAS, extending beyond the 20 commonly regulated compounds. This innovative method effectively identified previously unmonitored PFAS, such as perfluoropropanoic acid (PFPrA), underscoring the importance of a comprehensive PFAS profile in food safety and risk assessment. This work aims to support regulatory compliance and public health initiatives by revealing a wider chemical spectrum in food matrices.

Xanthippi Theurillat from Nestlé Research Lausanne, Switzerland, then gave a presentation entitled: “PFAS Analysis in Food: A Multi-Technique Approach for Regulatory Compliance and Consumer Protection.”Theurillat discussed Nestlé’s multi-faceted approach to comply with European PFAS regulations in food products. Addressing the total weekly intake (TWI) limits set by the European Food Safety Authority (EFSA) for specific PFAS, she emphasized the need for multiple analytical techniques. While LC–MS/MS is the primary tool for quantifying regulated PFAS, gas chromatography (GC) is utilized for volatile compounds, and LC–HRMS offers broader scope for emerging PFAS of interest. Nestlé’s method is adaptable to anticipated regulatory changes, according to Theurillat, reflecting an evolving commitment to consumer safety amidst increasing scrutiny of PFAS contamination.

Consolato Schiavone gave a talk entitled: “PFAS in Fruits and Vegetables: An Interlaboratory Validation Study on the Achievability of EU Targeted LOQs." Schiavone’s study addressed the validation of PFAS detection in fruit and vegetable samples. Working across laboratories, his team validated an analytical method based on LC–MS/MS and HRMS, testing its capacity to meet EU standards. These results , according to Schiavone, highlighted the need for reliable, standardized PFAS quantification methods to safeguard public health, enabling regulators to better assess PFAS exposure in diverse food types and advancing EU food safety legislation.

Nicolas Macorps from ONIRIS, France presented on “Non-Targeted Screening for PFAS in Complex Food Matrices: Keys to Data Prioritization." Macorps shared insights into non-targeted screening (NTS) for PFAS using high-resolution mass spectrometry to tackle the challenge of unknown PFAS in food. Utilizing data reduction tools such as isotopic pattern matching and Kendrick mass defect analysis, his team created a workflow to prioritize PFAS features for identification. This approach enables more effective PFAS profiling in complex food samples, advancing food safety research by identifying previously untracked PFAS compounds, according to Marcops.

Ingus Perkons, from the Institute of Food Safety, Animal Health, and Environment (BIOR), Latvia, presented a talk titled "Making Polychlorinated Alkane Analysis in Food More Accessible: Exploring Low-Resolution LC–MS/MS as a Suitable Alternative to LC-HRMS and GC-HRMS." Collaborating with Anna Skrastiņa and Laura Lazdiņa, he discussed the urgent need for simpler, more cost-effective methods for analyzing polychlorinated alkanes (PCAs) in food. PCAs, key components in chlorinated paraffin mixtures, are prevalent in industrial products such as flame retardants and plasticizers. However, these compounds persist in the environment and accumulate in the food chain, posing significant health risks. Although HRMS is commonly used for this purpose, its high cost limits accessibility for many laboratories. To address this, Perkons and his team developed a low-resolution LC–MS/MS method as a more accessible alternative for PCA analysis. This method was specifically optimized for the C10-17Cl5-8 PCA range and validated against an LC–HRMS method, showing comparable accuracy and consistency. The presentation covered essential aspects of method development, including the choice of mobile phase additives (ammonium chloride and ammonium acetate) to enhance ionization and fragmentation, selection of reversed-phase stationary phases for better resolution, and optimization of LC gradient conditions. This new approach provides a more accessible, robust solution for PCA quantification, potentially expanding capabilities for environmental food analysis, according to Perkons.

Paula Albendea from the University of Liège, Belgium presented on the "Study of Mineral Oil Hydrocarbons in Unprocessed Meat Using LC-GC×GC–FID/MS." Albedena focused on the analysis of mineral oil hydrocarbons (MOH), contaminants from environmental and industrial sources found in food. Albendea highlighted the shift from traditional LC–GC–FID methods to more advanced techniques such as LC-GCxGC–FID, driven by a need for detailed MOH profiling. The new method optimized a sample preparation method using microwave-assisted saponification on various meat types, achieved better recovery and internal standard distribution, according to Albendea. The study provided insights into the complexity of MOH, particularly differentiating between linear and cyclic saturated hydrocarbons (MOSH), aligning with recent EFSA recommendations, she concluded.

Jakub Tomasko from the University of Chemistry and Technology Prague, Czech Republic discussed “Chlorinated Paraffins in Insect-Based Foods." Tomasko and his team investigated short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) in edible insects. These emerging contaminants pose health risks like endocrine disruption and potential carcinogenicity, according to Tomasko. Using a validated GC–NCI-HRMS method, he analyzed samples from the Czech market and farms, finding higher contaminant levels in farm samples. Despite low dietary exposure in the Czech Republic, the study suggested that insect-based foods might significantly increase overall intake due to their rising consumption, he concluded.

Finally, Martin Lommatzsch from Laboratory Lommatzsch & Säger GmbH, Germany: presented on “Analytical Strategies for 3-7 Ring MOAH in Food.” Lommatzsch explored advanced analytical methods for detecting mineral oil aromatic hydrocarbons (MOAH), focusing on compounds with 3-7 aromatic rings linked to carcinogenic risks. The presentation outlined two approaches: a comprehensive GCxGC analysis for separating 1-2 and 3-7 ring MOAH, and an HPLC–GC–FID method with a donor-acceptor complex column for further fractionation. These techniques aim to enhance exposure assessments and address EFSA's concerns over the lack of data on lower-ring MOAH toxicity.