Improved Quantitation for EPA Method 1633 Using Post Extraction Matrix Reduction

Per- and Polyfluoroalkyl Substances (PFAS) in the Environment
Oral Presentation

Prepared by M. Giardina1, E. Parry2, L. Zhao1
1 - Agilent Technologies, 2850 Centerville Rd, Wilmington, DE, 19808-1610, United States
2 - Agilent Technologies, 2850 Centerville Rd, Wilmington, DE, United States


Contact Information: [email protected]; 302-636-8211

ABSTRACT

This study assesses a modified EPA Method 1633 sample preparation workflow for quantifying per and polyfluoroalkyl substances (PFAS) in biosolids, using NIST SRM 2781 sewage sludge as a matrix analog. Initial extraction employed dual phase blended solid phase extraction (SPE) cartridges containing 200 mg weak anion exchange (WAX) and 50 mg carbon sorbents. Compared to layered cartridges of equivalent bed mass, the blended configuration provided higher permeability and reduced clogging from fine particulates. To further minimize matrix interferences, the syringe filtration step specified in EPA Method 1633 was replaced with a post extraction cleanup using enhanced matrix reduction (EMR) cartridges designed for PFAS applications. Recovery accuracy and precision were evaluated across 40 PFAS targets with and without EMR cleanup. Extracts treated with EMR showed more consistent recoveries, while several deviations in non EMR extracts were linked to coelution and signal suppression. Overall, integrating blended SPE sorbents with EMR cleanup improves PFAS quantitation in biosolids and supports broader adoption of this workflow for complex solid matrices.