Quantitation of Extractable Per- and Polyfluorinated Alkyl Substances (PFAS) in Consumer Products on the Shimadzu Triple Quadrupole Mass Spectrometer LCMS-8060NX

Importance of the Topic

Per- and polyfluoroalkyl substances (PFAS) are widely used in consumer goods for their water-, oil-, and heat-resistant properties. Their exceptionally strong carbon–fluorine bonds confer high stability and persistence in the environment and organisms. Growing evidence of PFAS bioaccumulation and potential health risks, coupled with regulatory bans on PFAS-containing products, drives the need for accurate, sensitive, and standardized analytical methods to quantify extractable PFAS in solid consumer matrices.

Objectives and Study Overview

This study aimed to develop a streamlined, cost-effective workflow for quantifying 46 PFAS and 25 isotopically labeled surrogates in solid samples (e.g., sand, nonstick foil, HDPE plastic) without labor-intensive solid-phase extraction. The method targets reporting limits of 100–4000 ng/kg to meet or exceed proposed ASTM standards.

Methodology and Instrumentation

Sample Preparation:

• Accurately weigh 0.5 g of sample into a polypropylene tube and spike with surrogate solution.
• Perform co-solvation extraction using 50:50 methanol:water and adjust pH to 9–10 with ammonium hydroxide.
• Tumble for 2 hours, filter through 0.2 µm polypropylene, then adjust filtrate to pH 3–4 with acetic acid.
• Centrifuge at 3000 rpm, 8 °C for 15 min and transfer supernatant to PFAS-free silanized vials.

Chromatography and Detection:

• Shimadzu Nexera UHPLC with a PFAS Delay guard column and Shim-pack Scepter C18 analytical column.
• Gradient elution from 5% to 95% acetonitrile over 14 min at 0.45 mL/min.
• Shimadzu LCMS-8060NX triple quadrupole MS with IonFocus ESI(–) source; multiple reaction monitoring for quantitation and confirmation ions.
• Co-injection of sample with 0.1% acetic acid to improve early eluting peak shapes.

Used Instrumentation

• Shimadzu Nexera UHPLC (LC-40D X3 pumps, SIL-40C autosampler, SCL-40 controller, CTO-40C oven)
• Shimadzu LCMS-8060NX with IonFocus ESI source
• Shimadzu Nexcol PFAS Delay column (3.0 × 50 mm, 5 µm)
• Shim-pack Scepter C18-120 column (2.1 × 100 mm, 3 µm)

Main Results and Discussion

• Reporting limits of 100 ng/kg for most PFAS (range up to 4000 ng/kg) achieved via co-solvation and large-volume injection.
• Calibration curves (7–9 points) showed linearity with %RSD of response factors below 20%, meeting ASTM requirements.
• Co-injection technique markedly improved peak shapes for early eluting PFPrA, PFBA, and PFPeA.
• Surrogate recoveries in sand, plastic, and foil ranged from 85% to 130% with RSDs under 15% across triplicate extractions.

Benefits and Practical Applications

This approach eliminates solid-phase extraction, reducing sample preparation time and cost. Its high sensitivity and robustness support regulatory testing of PFAS in various consumer products and facilitate inter-laboratory reproducibility.

Future Trends and Applications

• Standardization of PFAS quantitation methods under ASTM guidelines.
• Extension of the workflow to additional matrices, including paper, textiles, and coatings.
• Integration with high-resolution or non-targeted MS for comprehensive PFAS screening.
• Automation of co-solvation extraction and co-injection for increased throughput.

Conclusion

The presented co-solvation workflow on the Shimadzu LCMS-8060NX provides a streamlined, robust, and sensitive method for quantifying extractable PFAS in solid consumer products. By removing solid-phase extraction, it offers efficiency gains and meets stringent reporting limits, laying the groundwork for standardized PFAS analysis.

References

1. Agency for Toxic Substances and Disease Registry (ATSDR). Toxicological Profile for Per- and Polyfluoroalkyl Substances (PFAS).
2. Underwriters Laboratories (UL). More U.S. States Ban PFAS-Containing Products.
3. ASTM D8421-22. Standard Test Method for Determination of Per- and Polyfluoroalkyl Substances in Aqueous Matrices by Co-solvation and LC-MS/MS.
4. ASTM D7968-17a and D7979-20. Guides for Mass Spectrometry Method Validation.