Determination of Per- and Polyfluorinated Alkyl Substances (PFAS) in Drinking Water Using Automated Solid Phase Extraction and LC-MS/MS for U.S. EPA Method 533

Polyfluoroalkyl Substances (PFAS) in the Environment
Oral Presentation

Presented by C. Shevlin
Prepared by X. Zhang
Thermo Fisher Scientific, 1214 Oakmead Parkway, Sunnyvale, California, 94085, United States


Contact Information: xin.zhang@thermofisher.com; 1 408-769-9786


ABSTRACT

Drinking water perfluorinated and polyfluorinated alkyl substances (collectively referred to as PFAS) occurrence studies have typically targeted perfluorooctanoic acid(PFOA) and perfluorooctanesulfonate (PFOS), and as a result, these two are the most commonly detected compounds. However, other compounds including PFBA, PFHxA, PFHpA, PFNA, PFUnDA, and PFHxS have also been detected in drinking water. In December 2019, the United States Environmental Protection Agency (U.S. EPA) took a key step in implementing the PFAS Action Plan by announcing a new validated method for testing PFAS in drinking water. This new validated test method complements other actions the agency is taking under the Action Plan to help communities address PFAS nationwide.
The new method, U.S. EPA 533, focuses on “short chain” PFAS, those PFAS with carbon chain lengths of four to twelve, and covers PFOS, PFOA, and other common PFAS that have been detected and reported. Currently most testing laboratories areperforming the sample extraction manually using a vacuum manifold, which is labor-intensive and time-consuming. In addition, the flow rate through the cartridge is difficult to control, which may yield low recoveries or cause false
negatives. There is a high demand for automation of the SPE procedure. Here we discuss the development of an analytical method using an automated SPE system and LC-MS/MS for determination of twenty-five PFAS compounds following the guidelines provided by U.S. EPA Method 533.