Analysis of Per-and Polyfluoroalkyl Substances (PFASs) in Non-Drinking Water Matrices Using the LC-Triple Quadrupole Mass Spectrometer

Significance of the Topic

Per- and polyfluoroalkyl substances (PFAS) are widespread environmental pollutants of growing regulatory concern. Their persistence, toxicity and bioaccumulative potential demand robust analytical methods to monitor trace levels in non-potable water matrices such as groundwater, surface water and wastewater. The development and validation of a comprehensive LC-MS/MS protocol enables laboratories to comply with emerging EPA guidance and to safeguard public and ecological health.

Study Objectives and Overview

The primary goal of the work was to evaluate and demonstrate the performance of the Shimadzu LCMS-8050 triple quadrupole mass spectrometer in conjunction with draft EPA SW-846 Method 8327. Specific objectives included:

• Quantitative analysis of 24 target PFAS compounds and 19 isotopically labeled surrogates across multiple water types.
• Determination of method reporting limits, accuracy, precision and linearity in complex matrices.
• Assessment of contamination control measures and instrument robustness for routine high-throughput analysis.

Methodology and Instrumentation

Sample preparation followed a simplified dilution and surrogate spiking protocol using polypropylene labware to minimize PFAS background. Water samples (5 mL) were fortified with 19 labeled standards, mixed with methanol, vortexed, filtered and acidified prior to analysis. Chromatographic separation employed a phenyl-hexyl column (2.1 × 100 mm, 3 µm) with a gradient of ammonium acetate buffers in water and acetonitrile at 0.3 mL/min. Mass spectrometric detection used multiple reaction monitoring (MRM), optimizing two transitions per analyte. A delay column and rigorous blank injections eliminated system-borne PFAS contamination.

Instrumentation Used

• Shimadzu Nexera X2 SIL-30AC autosampler
• Shimadzu LCMS-8050 triple quadrupole mass spectrometer
• Shim-pack GIST Phenyl-Hexyl analytical column
• Shim-pack XR-ODS delay column

Results and Discussion

Calibration was achieved over 5–200 ng/L with 1/x weighting, yielding R² > 0.99 and residuals within ±30%. Method reporting limits were below 5 ng/L for all targets. Mean recoveries in reagent water, groundwater, surface water and wastewater ranged between 84%–96% at mid (40 ppt) and high (80 ppt) levels with relative standard deviations <10%. Surrogate recoveries in complex matrices met acceptance criteria (70%–130%, RSD ≤20%). Total run time per injection was 21 minutes, including column wash, demonstrating a balance between throughput and resolution. Chromatograms at low-level calibrators showed clear separation of isomers and consistent peak shapes across matrices, confirming robustness against interferences.

Benefits and Practical Applications

This method provides analytical laboratories with:

• Certified compliance with EPA draft SW-846 Method 8327.
• High sensitivity for regulatory PFAS monitoring in non-drinking waters.
• Streamlined sample preparation compatible with high-throughput workflows.
• Improved precision and lower quantitation limits compared to existing protocols.

Future Trends and Potential Applications

Advancements may include automation of sample handling, expansion to additional PFAS analogues and integration of isotopic dilution techniques for further accuracy. Emerging high-resolution MS platforms could offer non-targeted screening for novel PFAS, while coupling with passive sampling may enhance spatial monitoring. Method adaptation for solid and biota samples would broaden environmental risk assessment.

Conclusion

The Shimadzu LCMS-8050 system, following draft EPA SW-846 Method 8327, demonstrates rapid, reliable and highly sensitive quantitation of PFAS in challenging water matrices. The validated protocol meets or exceeds regulatory performance criteria, enabling laboratories to implement robust PFAS monitoring with minimal sample preparation and high throughput.

References

• Environmental Science and Technology. “Polyfluorinated Compounds: Past, Present, and Future.”
• Agency for Toxic Substances and Disease Registry. “Per- and Polyfluoroalkyl Substances (PFAS) and Your Health,” October 2018.
• U.S. Environmental Protection Agency. “Per- and Polyfluoroalkyl Substances (PFAS),” 2018.
• ASTM D7979-17. Standard Test Method for Determination of Per- and Polyfluoroalkyl Substances in Water by LC/MS/MS, 2017.