uantification of 16 EC priority PAH componentswith Magnetic Sector GC-HRMS

Significance of the Topic

PAHs pose health risks and are regulated in food. Magnetic sector GC-HRMS offers high selectivity and sensitivity for trace PAH quantification to comply with regulatory limits.

Objectives and Overview of the Study

Assess the performance of a Thermo Scientific DFS Magnetic Sector GC-HRMS system for quantitative analysis of 16 EC priority PAHs using isotope dilution and fast GC separation, aiming for routine compliance with European regulations.

Used Instrumentation

• Thermo Scientific DFS Magnetic Sector GC-HRMS
• Thermo Scientific TRACE GC Ultra with split/splitless injector
• Thermo Scientific TriPlus Autosampler
• Thermo Scientific ASE 200 Accelerated Solvent Extractor
• GPC system with Bio-Beads SX-3 column
• Modified ASPEC Xli for SPE clean-up

Methodology

Sample preparation combined pressurized solvent extraction with n-hexane, size exclusion chromatography for removal of high molecular weight interferences, and solid phase extraction on silica to eliminate polar co-extractives. Isotope dilution used 13C and deuterated PAH standards. Fast GC separation on a 10 m phenyl capillary column reduced analysis time to 25 min. Detection employed high resolution multiple ion detection with exact mass monitoring.

Main Results and Discussion

Fast GC reduced retention time from 90 to 25 minutes while preserving isomer resolution. The method achieved limits of detection as low as 0.005 μg/kg and quantification limits of 0.015 μg/kg in spice matrices. Recoveries ranged from 60 to 120% across different PAHs. Analysis of caraway seeds demonstrated quantification of benzo[a]pyrene at 0.02 μg/kg, below regulatory limits.

Benefits and Practical Applications

• High throughput analysis suitable for routine food testing laboratories
• Excellent selectivity and sensitivity for trace PAH monitoring
• Compliance with European maximum levels for infants, children, and smoked products

Future Trends and Possibilities

Further developments may include automation of sample preparation, integration of faster and more robust GC columns, expansion to additional matrices, and application of HRMS to emerging contaminants. Coupling with data processing algorithms could enhance throughput and data quality.

Conclusion

The combination of fast GC and magnetic sector GC-HRMS provides a reliable, rapid, and sensitive approach for quantification of priority PAHs in food. This workflow meets regulatory requirements and is adaptable for high-volume routine testing.

References

1. EC Regulation No 208/2005 amending maximum levels for PAHs in food.
2. EC Recommendation on investigation of PAHs in food, 4 February 2005.
3. JECFA Summary and Conclusion, 64th meeting on food additives, 2005.
4. Ziegenhals K., Jira W., Presentation at European HR GC-MS Users Meeting, Venice, 2007.
5. Ziegenhals K., Jira W., Kulmbach Kolloquium, 2006.
6. Kleinhenz S., Jira W., Schwind K.-H., Mol Nutr Food Res 50 (2006) 362-367.