Method Guide for PFAS Analysis - A Survey of Existing PFAS Testing Methods and Guidelines from Around the World

Importance of the Topic

Per- and polyfluoroalkyl substances (PFAS) are widely used in consumer products, industrial applications and firefighting foams. Their extreme persistence, bioaccumulation potential and toxicity create a pressing need for accurate and reliable analytical methods. Routine PFAS testing supports environmental monitoring, regulatory compliance and protection of human health.

Study Objectives and Overview

This guide surveys existing PFAS testing standards and guidelines published by major organizations (ISO, U.S. EPA, ASTM, DIN). It aims to help analytical laboratories select or refine workflows based on sample matrix, target analytes and regional regulations. A comparison of method scope, sample preparation and detection techniques is provided.

Methodology and Instrumentation

All surveyed methods share a common detection platform: liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Sample preparation varies by matrix:

• Solid phase extraction (SPE) with weak anion exchange (WAX), hydrophilic–lipophilic balance (HLB) or C18 sorbents for water samples.
• Direct injection for wastewater, sludge and certain ASTM soil methods.
• Solvent extraction for non-volatile PFAS in leather.
• Air sampling using XAD resin cartridges and impingers.

Main Results and Discussion

The compiled table of more than a dozen methods highlights:

• ISO standards targeting drinking water (ISO 25101, ISO 21675), leather (ISO 23702-1) and air (ISO OTM 45).
• U.S. EPA methods 537.1, 533 and 8327 for water matrices, OTM 45 for air, and draft EPA 1633 for complex matrices (soil, tissue, biosolids).
• ASTM methods D7979-19 (water, sludge, wastewater) and D7968-17a (soil).
• DIN 38407-42:2011 for water analysis.

Method scopes differ in target analyte lists (PFOS, PFOA, short-chain and emerging PFAS) and sample prep details. Laboratories must match method coverage to regional PFAS production and regulatory targets.

Benefits and Practical Applications

• Standardized LC-MS/MS workflows ensure reproducibility and sensitivity at low ng/L levels.
• Guidance on SPE sorbent selection and cleanup reduces matrix interferences.
• Flexibility to adapt methods for diverse matrices: water, soil, air, consumer goods.
• Support for regulatory compliance and risk assessment in environmental monitoring, food safety and occupational exposure.

Future Trends and Applications

As PFAS chemistry evolves, analytical trends will include:

• Non-targeted screening and high-resolution mass spectrometry to discover novel PFAS.
• Automated sample preparation for higher throughput and reduced operator variability.
• Expanded methods for food, biosolids, textiles and indoor air monitoring.
• Standard updates to include emerging short-chain and polymeric PFAS compounds.

Conclusion

Global PFAS testing guidelines provide a robust foundation for reliable analysis across matrices. LC-MS/MS remains the technique of choice, supported by tailored SPE or extraction protocols. Laboratories should select methods aligned with sample type, target compounds and local regulatory requirements, while staying informed on emerging standards and analytes.