High Throughput Solid Phase Extraction and Concentration of PFAS/PFOS in Ground and Waste Water Using EPA Method 533 and 537.1

Polyfluoroalkyl Substances (PFAS) in the Environment
Oral Presentation

Prepared by T. Hall, R. Addink
Fluid Management Systems, 900 Technology Park Dr, Billerica, MA, 01821, United States


Contact Information: thall@fms-inc.com; 617-393-2396

ABSTRACT

Extraction and analysis of Per- and Polyfluoralkyl Substances (PFAS/PFOS) in drinking water samples (EPA methods 533/537.1) has led in recent years to interest in similar analyses in ground water and waste water samples. An important problem with ground and waste water extraction is the presence of particulate matter which can easily plug up cartridges. We developed a method using the application of Delrin plastic filtration wool which completely eliminates this problem.

Automation of the sample concentration and evaporation will greatly speed up sample throughput and workflow for laboratories. A special 24-position evaporator was developed which can concentrate 24 samples in 15 mL plastic tubes to dryness as per 533/537.1 methods. This evaporator can also be used to concentrate ground and waste water extracts.

Twelve 250 mL ground or waste water samples were spiked with 2-50 ppt PFAS standards. Cartridges used were SDVB and WAX (Weak Anion Exchange). We followed both EPA methods for our extraction using a vacuum pump for conditioning, sample loading, drying, and elution and a nitrogen flow for automated bottle rinses. Use of Delrin filtration wool provided excellent cartridge filtration. Eluents were collected for analysis and reduced in volume with automated concentration; analysis with LC/MS.

30 PFAS from both methods were analyzed with recoveries between 85-120%. Data showed very good reproducibility. Ground and waste water samples are easily analyzed with both EPA methods using a simple laboratory SPE set-up and use of Delrin filtration wool. Automated concentration of PFAS extracts greatly increases laboratory throughput.