Analyses of PFOS and PFOA Precursors in Textile Products Using EI-MRM and PCI-SIM Method

Importance of the Topic

Persistent perfluoroalkyl substances such as PFOS and PFOA pose environmental and health risks due to their stability, bioaccumulation, and widespread use in water and stain repellent textiles. Analyzing trace-level precursors that can degrade into PFOS and PFOA is critical to meet regulatory requirements and protect ecological and human health.

Objectives and Study Overview

This study aims to develop and validate two complementary gas chromatography mass spectrometry methods to quantify PFOS and PFOA precursors—including perfluorooctane sulfonamides and perfluoroalkyl acrylates—in textile products. The methods compared are electron ionization multiple reaction monitoring (EI-MRM) on a triple quadrupole GC-MS/MS and positive chemical ionization selective ion monitoring (PCI-SIM) on a single quadrupole GC/MS. Performance metrics such as limits of detection and quantitation, matrix effects, accuracy, and repeatability were assessed, followed by application to commercial textile samples.

Methodology

Textile samples were cut into small squares and extracted with tetrahydrofuran at 60 °C for one hour. Extracts were filtered and concentrated tenfold prior to analysis. A deuterated naphthalene internal standard and D-sorbitol analyte protectant were used. Matrix-matched calibration standards were prepared in blank textile extracts. Chromatographic separation was achieved within seven minutes on an Rtx-200 column under splitless injection.

Instrumentation Used

• Triple quadrupole GC-MS/MS system GCMS-TQ8050 NX for EI-MRM analysis
• Single quadrupole GC/MS system GCMS-QP2020 NX for PCI-SIM analysis
• Auto-injector AOC-20i + 20s
• Column SH-Rtx-200 (30 m × 0.32 mm I.D., 0.5 µm film)

Main Results and Discussion

EI-MRM achieved instrument detection limits as low as 0.5 ng/mL for sulfonamide precursors and 1–4 ng/mL for other targets, with a quantitation limit of 5 ng/mL for all analytes. PCI-SIM provided an LOD of 4 ng/mL and LOQ of 5 ng/mL. Both methods exhibited excellent linearity (R2 ≥ 0.998), repeatability (%RSD ≤ 18% for EI-MRM and ≤ 13% for PCI-SIM), and accuracy within ±30% across low, mid, and high spikes. Matrix effects ranged from slight suppression to enhancement around 100%, supporting the use of matrix-matched calibration. Applied to real samples, EI-MRM detected N-MeFOSE and N-EtFOSE at 1.74 and 2.91 ng/g in fabric blends, while PCI-SIM detected FTA 8:2 and FTA 10:2 at 89.8 and 41.0 ng/g in umbrella material, findings that were confirmed by EI-MRM.

Benefits and Practical Applications

• EI-MRM enables ultra-trace quantitation of PFAS precursors below regulatory thresholds
• PCI-SIM offers rapid screening for routine quality control
• Matrix-matched approach ensures reliable quantitation in complex textile matrices
• Short analysis time and robust performance support high-throughput laboratories

Future Trends and Applications

Emerging high-resolution mass spectrometry and automated sample preparation will further improve sensitivity and selectivity for new PFAS compounds. Green extraction techniques and AI-driven data analysis are expected to streamline workflows. Integration into regulatory monitoring and environmental compliance programs will expand the use of these methods in industrial and research settings.

Conclusion

The EI-MRM and PCI-SIM GC/MS methods provide complementary strengths for analyzing PFOS and PFOA precursors in textiles. EI-MRM delivers superior sensitivity for trace detection, while PCI-SIM supports efficient screening. Both methods meet stringent regulatory requirements and offer reliable quantitation in complex matrices.

References

• The 16 New POPs. Conference of the Parties to the Stockholm Convention, June 2017
• PFOA Restriction in Norway. Product regulation FOR 2004-06-01 Nr. 922, Section 2-32
• OECD Report ENV/JM/MONO(2006)15 on PFOS and related substances
• EU Commission Regulation 2017/1000 amending REACH Annex XVII regarding PFOA and related substances