LC/MS/MS Method Package for PFAS in Drinking Water

Importance of the Topic

Per- and polyfluoroalkyl substances display unique properties such as water and oil repellency, chemical stability, and thermal resistance. However, their environmental persistence, potential for bioaccumulation, and adverse health effects have prompted global regulatory action and monitoring efforts. Reliable quantification of PFAS in drinking water is critical to protect public health and comply with evolving standards.

Objectives and Study Overview

This method package is designed to standardize and streamline quantitative analysis of PFAS in drinking water according to EPA Methods 533 and 537.1. It provides ready-to-use LC/MS/MS methods, detailed procedures, and practical guidance to measure up to 52 PFAS compounds, facilitating implementation in regulatory and research laboratories.

Methodology

• Sample preparation following EPA solid phase extraction protocols
• Chromatographic separation using reverse-phase columns with ammonium acetate buffer
• Tandem mass spectrometry detection with multiple reaction monitoring (MRM)
• Quantification based on isotope dilution using labeled internal standards and surrogate analogues
• Calibration ranges covering minimum reporting levels and higher concentrations

Used Instrumentation

• Shimadzu LCMS-8050 triple quadrupole mass spectrometer
• Shimadzu high-performance liquid chromatography system
• LabSolutions LCMS software version 5.113 or later
• LabSolutions Insight software version 3.8 SP3 or later
• Optional PFAS analysis kit for reduced analyte adsorption in fluid paths

Main Results and Discussion

The method package enables rapid separation and detection of PFAS within typical run times of 3–8 minutes, achieving precise quantitation of 18 compounds for Method 537.1 and 25 compounds for Method 533. Representative chromatograms confirm clear peak resolution and consistent retention times. The use of isotopically labeled surrogates ensures accuracy, while documented procedures minimize variability across laboratories.

Benefits and Practical Applications

• Immediate deployment with pre-optimized analytical conditions
• Compliance with UCMR5 monitoring requirements in the United States
• Enhanced laboratory throughput and reproducibility
• Flexibility to monitor a broad spectrum of regulated and emerging PFAS

Future Trends and Potential Applications

Advancements may include expansion of target analyte lists to cover novel PFAS, integration of high-resolution mass spectrometry, and automation of sample preparation through on-line solid phase extraction. Collaborative method harmonization and data sharing are expected to support global monitoring initiatives and risk assessment.

Conclusion

The LC/MS/MS method package for PFAS in drinking water provides a comprehensive solution for regulatory-compliant quantitation of a wide array of PFAS compounds. Its robust performance, coupled with detailed guidance and software integration, empowers laboratories to address pressing environmental and public health challenges.

References

• US Environmental Protection Agency. Method 537.1 Determination of Selected Per- and Polyfluorinated Alkyl Substances in Drinking Water by Solid Phase Extraction and Liquid Chromatography Tandem Mass Spectrometry. EPA 815-B-18-002, 2018.
• US Environmental Protection Agency. Method 533 Determination of Per- and Polyfluoroalkyl Substances in Drinking Water by Solid Phase Extraction and Liquid Chromatography Tandem Mass Spectrometry. EPA 810-R-19-006, 2019.
• Stockholm Convention on Persistent Organic Pollutants. Adopted 2001. Accessed January 14, 2022.
• US Environmental Protection Agency. Fifth Unregulated Contaminant Monitoring Rule UCMR 5. EPA, 2023.