Exploring PFAS in Consumer Goods Using GCxGC and High-Resolution Mass Spectrometry

Significance of the Topic

The widespread use of per- and polyfluorinated alkyl substances (PFAS) in industrial and consumer goods has raised concerns due to their persistence, bioaccumulation potential and health effects. Analytical methods capable of uncovering both known and unknown PFAS in complex matrices are critical for regulatory compliance, product safety and environmental monitoring.

Objectives and Study Overview

This study aimed to develop an untargeted screening workflow for PFAS in consumer products, demonstrating its application on two representative samples: an anti-fog solution and chewing gum. Key goals included improving chromatographic resolution, reducing matrix interferences and achieving high-confidence compound identification through accurate mass measurements.

Methodology and Sample Preparation

Samples were introduced by thermal desorption or pyrolysis using a quartz inlet. Liquid anti-fog formulations were diluted in acetone, while gum samples were placed in microtubes. Analytical runs employed both conventional GC-TOFMS and comprehensive two-dimensional GC×GC coupled with high-resolution time-of-flight MS (HRTOFMS). Multi-mode ionization (electron impact, positive and negative chemical ionization) provided complementary fragmentation and molecular information.

Used Instrumentation

• Thermal desorption/pyrolysis inlet (GL Sciences Optic-4)
• LECO Pegasus BTX 4D GC-TOFMS
• LECO Pegasus HRT+ 4D GC×GC HRTOFMS with multi-mode source

Results and Discussion

• Anti-Fog Solution: Chromatograms revealed fluorotelomer alcohols (6:2, 8:2, 10:2 FTOH), N-MeFOSA and other PFAS among aliphatic, aromatic and heterocyclic compounds. High-resolution MS enabled molecular formula assignment and ring-double bond equivalent (RDBE) calculations to confirm PFAS structures and distinguish them from matrix components.
• Chewing Gum: The complex matrix of sugars, terpenes, fatty acids and additives was resolved by GC×GC, yielding clean spectra for individual constituents. Mass defect filtering specifically targeting CF2 units allowed screening for PFAS. No PFAS were detected in gum, packaging or wrapping materials under the tested conditions.

Benefits and Practical Applications

• The combined GC×GC-HRTOFMS workflow supports non-targeted screening of diverse consumer products for PFAS and other emerging contaminants.
• High chromatographic resolution and mass accuracy reduce false positives and improve confidence in unknown identification.
• Multi-mode ionization expands the range of detectable compounds, covering both electron-rich and electron-deficient species.

Future Trends and Potential Applications

• Integration with public spectral and chemical databases (e.g., EPA CompTox, ChemSpider) and machine-learning tools to streamline structure elucidation.
• Extension of the workflow to other consumer goods, environmental samples and biological matrices.
• Development of targeted quantitation assays for newly discovered PFAS and regulatory compliance.

Conclusion

This work demonstrates a powerful untargeted GC×GC-HRTOFMS approach for PFAS screening in complex consumer products. The methodology combines enhanced separation, high-resolution accurate mass data and mass defect filtering to detect, identify and characterize both known and novel PFAS with high confidence.

Reference

• Alonso DE, Binkley J. Exploring PFAS in Consumer Goods Using GC×GC and High-Resolution Mass Spectrometry. LECO Application Note.