CWA Analytical Methods for Per- and Polyfluorinated Alkyl Substances (PFAS)
EPA is developing new analytical methods to test for PFAS compounds in wastewater, as well as other environmental media.
There are hundreds of different PFAS chemicals of varying carbon chain lengths and different functional groups. Analyzing them in a comprehensive way has been a challenge that scientists at all levels of government are working to address. EPA has published methods to test for certain PFAS in drinking water and in non-potable water and continues to work on methods for other matrices.
Draft Method 1633 for 40 PFAS Compounds
Office of Water, in partnership with the Department of Defense’s (DoD) Strategic Environmental Research and Development Program, has published draft Method 1633, a single-laboratory validated method to test for 40 PFAS compounds in wastewater, surface water, groundwater, soil, biosolids, sediment, landfill leachate, and fish tissue. This draft method can be used in various applications, including National Pollutant Discharge Elimination System (NPDES) permits. The method will support NPDES implementation by providing a consistent PFAS method that has been tested in a wide variety of wastewaters and contains all the required quality control procedures for a CWA. While the method is not nationally required for CWA compliance monitoring until EPA has promulgated it through rulemaking, it is recommended now for use in individual permits.
Historically, EPA published draft methods on this Clean Water Act Methods website after completing the single-laboratory validation report. However, due to many public and stakeholder requests, this method is being made available while EPA prepares the single-laboratory validation study report.
A revision of this draft method may be published later. No procedural changes are expected to result from the single-laboratory validation, but some of the performance data (which are presented only as examples) may change once the statistical analysis of the single-laboratory validation data is completed.
Multiple EPA programs have reviewed this draft method. DoD expects to begin a multi-laboratory validation study of the procedure in 2021 and complete it in 2022, in collaboration with the Office of Water and the Office of Land and Emergency Management.
The Office of Water will use the results of the multi-laboratory validation study to finalize the method and add formal performance criteria. The method validation process may eliminate some of the parameters listed in this draft method.
In the meantime, the Office of Water encourages laboratories, regulatory authorities, and other interested parties to review and use the draft method, with the understanding that it is subject to revision.
Draft Method 1633 for the analysis of PFAS in aqueous, solid, biosolids, and tissue samples by LC-MS/MS (pdf) (821-D-21-001, August 2021)