Simultaneous Analysis of 40 PFAS Components in Drinking Water Using a Triple Quadrupole LC/MS/MS

Importance of the Topic

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental pollutants of growing regulatory concern. Their stability and resistance to degradation allow them to accumulate in water supplies, posing potential health risks. Robust analytical methods that can simultaneously quantify a broad range of PFAS at trace levels are essential for compliance monitoring, environmental research, and public health protection.

Objectives and Study Overview

This study evaluated the performance of the Shimadzu LCMS-8050RX triple-quadrupole LC-MS/MS system for the simultaneous analysis of 40 PFAS compounds in drinking water. Key aims included:

• Developing a 20-minute UHPLC-MS/MS method with high sensitivity and selectivity.
• Establishing calibration linearity and repeatability over a wide concentration range (0.2–250 ng/L).
• Validating recovery and precision in spiked drinking water at low and high concentration levels relative to current EPA maximum contaminant levels (MCLs).

Methodology and Instrumentation

Samples were pretreated by adding internal standards and extracting PFAS via anion-exchange solid-phase extraction (SPE) using the AquaTrace automated SPE system. Eluates were dried under nitrogen, reconstituted in methanol, and injected onto the UHPLC system. Chromatographic separation employed a Shim-pack GIST-HP C18 analytical column with a solvent delay (Shim-pack GIST C18) to reduce background contamination. The mobile phase consisted of 2 mM ammonium acetate in 5 % acetonitrile (A) and pure acetonitrile (B) under a multi-step gradient at 0.4 mL/min. The LCMS-8050RX operated in negative-mode electrospray ionization with multiple reaction monitoring (MRM), leveraging CoreSpray technology for uniform nebulization.

Used Instrumentation

• Shimadzu Nexera-X3 UHPLC system
• Shim-pack GIST-HP C18 analytical column (50 × 2.1 mm, 3 µm)
• Shim-pack GIST C18 delay column (50 × 2.1 mm, 5 µm)
• Shimadzu LCMS-8050RX triple-quadrupole mass spectrometer
• GL Sciences AquaTrace automatic SPE system

Main Results and Discussion

The method achieved baseline separation of all 40 PFAS within a 20-minute run time. Limits of quantitation reached as low as 0.2 ng/L for key analytes (PFOA, PFOS, PFHxS, PFNA, HFPO-DA). Calibration exhibited excellent linearity (RF %RSD < 20 % for all 40 compounds, < 10 % for 34 compounds). At the lowest calibration level (CS1), area repeatability (%RSD) was < 20 % for 87.5 % of targets and < 10 % at mid-level (CS3) for all.

In recovery tests, low-spike samples (around 1× MCL) yielded 70–130 % recovery for 90 % of compounds with RSD < 20 % for 95 %. High-spike samples (5–10× MCL) showed 70–130 % recovery for 97.5 % of analytes with RSD < 13 %. These results satisfy EPA Method 1633 performance criteria and demonstrate robust accuracy and precision in drinking water matrices.

Practical Benefits and Applications

• Rapid high-throughput analysis of multiple PFAS without sensitivity loss.
• Trace-level quantitation suitable for regulatory compliance monitoring.
• Automated SPE workflow reduces hands-on time and contamination risk.
• Wide dynamic range supports both screening and targeted quantitation.

Future Trends and Potential Applications

Advances may include expansion to non-target and emerging PFAS compounds via high-resolution MS, integration of miniaturized or field-deployable platforms for on-site monitoring, and automated data processing with artificial intelligence to accelerate large-scale water quality surveys. Continued instrument sensitivity improvements will support ever-lower regulatory thresholds.

Conclusion

The Shimadzu LCMS-8050RX system delivers high sensitivity, speed, and robustness for simultaneous quantitation of 40 PFAS in drinking water. It meets stringent regulatory requirements, offering a reliable solution for environmental laboratories and regulatory agencies.

Reference

• EPA Method 1633: Analysis of Per- and Polyfluoroalkyl Substances (PFAS) in Aqueous, Solid, Biosolids, and Tissue Samples by LC-MS/MS