This report is the first in a series presenting the results of a multi-laboratory validation study (MLVS) designed to validate Environmental Protection Agency (EPA) draft Method 1633 for analysis of per- and polyfluoroalkyl substances (PFAS) in aqueous, solid, biosolids, and tissue matrices by LC-MS/MS. This study was funded by SERDP and ESTCP and conducted as a joint effort by the U.S. Department of Defense (DoD) and the EPA.  

The primary objectives of the MLVS were to (1) evaluate the robustness of EPA draft Method 1633 when performed by suitable laboratories using similar instrumentation, and (2) provide information on the range of precision and accuracy of quantitation that is achievable by suitable laboratories. This was achieved by sending ten commercial and State laboratories PFAS-spiked environmental samples for analysis by EPA draft Method 1633. Briefly, environmental samples of each matrix type were sent to each laboratory as an unspiked (or "native") sample, three replicates at a low spike concentration, and three replicates at a high spike concentration. The data from all laboratories were aggregated for statistical analyses and derivation of quality control acceptance criteria reflecting method performance in real-world situations.
The results of this study will be used to modify the draft method into its final form and establish quality control criteria to be used going forward. 

The results presented in this report are for the aqueous matrices of groundwater, surface water, and wastewater. With the completion of this phase of the study, the EPA has finalized EPA Draft Method 1633 for wastewater, surface water, and groundwater matrices. Additional reports will be published for the remaining matrices (landfill leachate, soil, sediment, biosolids, and tissues) as they become available. 

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About SERDP & ESTCP

The Strategic Environmental Research and Development Program (SERDP) and the Environmental Security Technology Certification Program (ESTCP) harness the latest science and technology to improve the Department of Defense’s environmental performance, reduce costs, and enhance and sustain mission capabilities. The programs respond to energy and environmental technology requirements across the military services. SERDP and ESTCP are independent DoD programs managed jointly to coordinate the full spectrum of research and development efforts, from the laboratory to field demonstration and validation. For more information, visit https://www.serdp-estcp.org. Follow us on Twitter, Facebook, and LinkedIn.