Robustness Evaluation of PFAS Analysis in Soil Using LCMS -8060RX

Importance of the Topic

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are persistent contaminants used across industries and consumer products. Their strong carbon–fluorine bonds render them resistant to environmental degradation and prone to bioaccumulation, raising regulatory and health concerns. Agencies such as the US EPA and ECHA have tightened PFAS limits, driving demand for robust, sensitive methods capable of quantifying trace PFAS in complex matrices like soil.

Objectives and Study Overview

This study assessed the analytical robustness of the Shimadzu LCMS-8060RX triple-quadrupole mass spectrometer with CoreSpray nebulization for quantifying 30 PFAS in a soil matrix. A soil sample spiked at 0.1 µg/L was analyzed 500 consecutive times to evaluate repeatability, sensitivity, and long-term stability.

Methodology and Instrumentation

The LCMS-8060RX platform combines ultra-fast UF technology with CoreSpray for uniform nebulization. A Shim-pack Scepter C18 column (100 × 2.1 mm, 1.9 µm) and a delay column minimized PFAS carryover. Mobile phases comprised 2 mM ammonium acetate in water (A) and methanol (B) under a gradient from 1 % to 100 % B over 15 minutes. ESI (negative mode) was operated with MRM transitions for each compound. Key parameters:

• Flow rate: 0.3 mL/min; column temperature: 40 °C; injection volume: 5 µL; run time: 20 min.
• Nebulizing gas: 3 L/min; drying gas: 5 L/min; heating gas: 15 L/min; interface temperature: 250 °C.

Main Results and Discussion

Calibration curves for all 30 PFAS over 0.01–10 µg/L (and 0.05–5 µg/L for two compounds) exhibited coefficients of correlation (R) above 0.996. Peak shapes were sharp and retention times reproducible near 12 minutes. In the soil matrix, 500 sequential injections yielded peak-area RSDs below 8.5 % for all analytes; detection limits ranged from 0.011 to 0.020 µg/L. Quality control samples injected every 20 runs maintained recoveries between 80 % and 120 % throughout the sequence, confirming analytical stability.

Benefits and Practical Applications

The LCMS-8060RX with CoreSpray delivers:

• High throughput analysis with minimal drift over extended sequences.
• Reliable quantitation of low-level PFAS in soil and other complex environmental matrices.
• Compliance support for regulatory monitoring and risk assessment.

Future Trends and Potential Applications

Advancements may include integration with automated sample preparation and high-resolution MS for unknown PFAS screening. Expanding this platform to water, biota, and industrial samples will support comprehensive environmental surveillance. Miniaturized flow systems and green solvent alternatives could further enhance sustainability and throughput.

Conclusion

The Shimadzu LCMS-8060RX equipped with CoreSpray technology demonstrates exceptional robustness for trace PFAS analysis in soil. Its stable performance over 500 injections, strong calibration linearity, and consistent recoveries establish it as a reliable tool for environmental laboratories addressing stringent PFAS regulations.

Reference

• National Agricultural and Food Research Organization. Draft Method 202201: Determination of PFAS in soil.
• MAFF/NARO. Basic research on PFAS movement from agricultural environments.