TRACE LEVEL DETERMINATION OF PER- AND POLYFLUOROALKYL SUBSTANCES (PFASs) IN WATER USING THE AGILENT 6460 LC/MS/MS

Importance of the topic

The per- and polyfluoroalkyl substances (PFAS) family consists of persistent, bioaccumulative compounds that pose environmental and health risks due to their widespread use and resistance to degradation. Accurate, low-level monitoring of PFAS in water is critical for assessing exposure, guiding remediation and meeting evolving regulatory standards worldwide.

Objectives and Study Overview

This work aimed to establish a sensitive, robust method for simultaneous determination of 26 PFAS in diverse water matrices. Key objectives included achieving method detection limits below 2 ng/L and ensuring applicability across marine water, surface water, groundwater, wastewater, landfill leachate, runoff and precipitation samples using solid-phase extraction (SPE) coupled with LC–MS/MS.

Methodology

• Sample preparation: SPE of 0.5 L water followed by elution and concentration to 1 mL.
• Calibration: Six-point calibration in methanol (0.05–40 ng/mL) with 16 isotopically labeled internal standards at 2 ng/mL.
• Detection: Negative electrospray ionization (ESI) in multiple reaction monitoring (MRM) mode on a triple quadrupole.

Used Instrumentation

• Agilent 1200 Series HPLC system
• Agilent 6460 Triple Quadrupole LC–MS/MS
• Analytical column: Betasil C18 (50 × 2.1 mm, 5 µm) with Hypersil Gold guard column

Main Results and Discussion

The method demonstrated excellent linearity (R² > 0.99) across 0.05–40 ng/mL for all analytes. Retention times spanned 3.9 to 14.1 minutes, enabling a 20-minute run time. Method detection limits were under 2 ng/L for each PFAS, and a surface water test sample revealed 10 target compounds in a single injection, highlighting method sensitivity and reproducibility.

Benefits and Practical Applications

• Supports compliance with drinking water guidelines and environmental regulations.
• Enables trace-level quantification for exposure assessment and source identification.
• Adaptable to routine QA/QC and research in academic, industrial and regulatory laboratories.

Future Trends and Potential Applications

Advancements in high-resolution MS and automated SPE are expected to enhance identification of novel PFAS and transformation products. Miniaturized extraction techniques and online sample introduction will improve throughput. Combining targeted quantitation with non-target screening and bioassays can deepen understanding of PFAS mixtures and toxic effects.

Conclusion

A validated SPE–LC–MS/MS workflow on the Agilent 6460 provides a reliable, high-throughput approach for quantifying 26 PFAS at trace levels in varied water matrices. This method offers laboratories a powerful tool for environmental monitoring, risk assessment and regulatory compliance.

References

1. Ahrens L. Polyfluoroalkyl compounds in the aquatic environment: a review of their occurrence and fate. Journal of Environmental Monitoring. 2011;13:20–31.
2. Ahrens L, Bundschuh M. Fate and effects of poly- and perfluoroalkyl substances in the aquatic environment: A review. Environmental Toxicology and Chemistry. 2014;33:1921–1929.
3. Stockholm Convention on Persistent Organic Pollutants. Report of the Conference of the Parties on the work of its fourth meeting. UNEP/POPS/COP.4/38. 2009.