Fast GC/HRMS Quantification of 16 EC Priority PAH Components

Importance of the Topic

Polycyclic aromatic hydrocarbons (PAHs) are widespread food contaminants with known carcinogenic properties, regulated by international authorities to protect consumer health.

Recent regulations set strict limits for PAH markers such as benzo[a]pyrene in various food matrices, highlighting the need for sensitive and high-throughput analytical methods.

Study Objectives and Overview

The study aimed to develop and validate a fast gas chromatography–high resolution mass spectrometry (GC–HRMS) method for quantifying 16 EU priority PAHs in foods including spices and smoked meats.

The objectives included reducing analysis time, achieving required selectivity and sensitivity, and ensuring compliance with EC and JECFA recommendations.

Applied Methodology

Sample purification combined pressurized solvent extraction (PSE), gel permeation chromatography (GPC) and solid phase extraction (SPE) to isolate lipophilic PAHs and remove high-molecular and polar interferences.

Isotope dilution quantitation employed isotopically labeled and fluorinated standards added before extraction to determine response factors and recoveries.

Used Instrumentation

• Thermo Scientific DFS High Resolution GC/MS system
• Thermo Scientific TRACE GC Ultra gas chromatograph
• Thermo Scientific TriPlus Autosampler
• ASE 200 pressurized solvent extractor
• GPC setup with Bio-Beads S-X3 column
• Automated SPE with modified ASPEC Xli system

Main Results and Discussion

Implementation of a fast GC column (10 m) reduced the chromatographic run from over 90 min to approximately 25 min while maintaining baseline separation and isotope resolution for all 16 PAHs.

Limits of detection and quantitation were estimated at 0.005 µg/kg and 0.015 µg/kg respectively, with recoveries ranging from 60% to 120% across various food matrices.

Analysis of caraway seed extracts demonstrated reliable quantification of benzo[a]pyrene at 0.02 µg/kg, below regulatory thresholds.

Benefits and Practical Applications

The method enhances sample throughput and laboratory productivity, enabling routine monitoring of PAH contamination in diverse food products.

High resolution MS provides the selectivity needed to comply with stringent regulatory limits, particularly at trace levels.

Future Trends and Potential Applications

Further miniaturization and automation of sample preparation could streamline workflows and reduce solvent use.

Expanding the approach to additional emerging contaminants and coupling with advanced data analysis or artificial intelligence tools may improve screening capabilities.

Conclusion

A fast GC–HRMS method has been established that meets regulatory requirements for sensitivity and selectivity, significantly reduces analysis time, and supports routine quality control of PAHs in food.

Reference

1. COMMISSION REGULATION (EC) No 208/2005 of 4 February 2005 amending Regulation (EC) No 466/2001 as regards polycyclic aromatic hydrocarbons.
2. COMMISSION RECOMMENDATION of 4 February 2005 on the further investigation into the level of polycyclic aromatic hydrocarbons in food.
3. Summary and Conclusion of the Joint FAO/WHO Expert Committee on Food Additives, Sixty-Fourth meeting, Rome, 8–17 February 2005, JECFA/64/SC.
4. Ziegenhals K., Jira W., High sensitive PAH method to comply with the new EU directives, Presentation at the European High Resolution GC/MS Users Meeting, Venice, Italy, March 23–24, 2007.
5. Ziegenhals K., Jira W., Bestimmung der von der EU als prioritär eingestuften polyzyklischen aromatischen Kohlenwasserstoffe (PAK) in Lebensmitteln, Kulmbach Kolloquium, Sept. 2006.
6. Kleinhenz S., Jira W., Schwind K.-H., Dioxin and polychlorinated biphenyl analysis: Automation and improvement of clean-up established by example of spices, Molecular Nutrition & Food Research 50(4-5), 2006, 362–367.