Per- and polyfluoroalkyl substances (PFAS) are released to the environment through several pathways, including use as aqueous film-forming foam (AFFF) for fire-control by the U.S. military. The U.S. Environmental Protection Agency has set health advisory levels for two PFAS based upon environmental persistence and adverse health outcomes, and multiple U.S. military bases and airports are subsurface contaminated with PFAS. Sampling and quantifying PFAS is required to remediate contaminated sites, but the process is time-consuming, requires costly instrumentation and expertise (liquid chromatography tandem mass spectrometry [LC-MS/MS]), and fails to capture many organofluorine transformation products and precursors with likely health impacts to exposed aquatic species and humans. The overarching objective of this project is to develop and validate robust, field-ready instrumentation and methods to quantify total organofluorine.

The objective will be met through four hypothesis-driven tasks, beginning with development of a portable, automated, total organofluorine instrument. This instrumentation and methodology could allow for more than 100 samples to be analyzed in the field in less than 24 hours. The methodology will be more robust than mass spectrometry-based approaches because it will capture all organofluorine-containing compounds. The methodology will be validated per Department of Defense (DoD) Quality Systems Manual requirements (QSM 5.1 Table B-15) and produce standard methods that conform to this manual’s guidelines. Follow-on research would modify the developed instrumentation by coupling it to high-performance liquid chromatography; this will provide species-specific identifiable peaks, and will discriminate between environmental fluorine/fluoride (e.g., fluoroacetate) and anthropogenic PFAS. The specific, hypothesis driven tasks are:

• Design, build, and develop combustion laser spectroscopy total fluorine instrumentation
• Validate method and compare to other PFAS methodology
• Mobilize and field demonstrate the instrumentation
• Develop instrumentation that results in species-specific quantitation of PFAS, per-fluoroalkyl acid (PFAA) precursors, and PFAS decomposition products

Expected benefits to the DoD include reduced labor associated with site profiling and reduced analytical lab costs and uncertainty, leading to better site characterization and reduced duration of site remediation. Expected benefits to the scientific community include an increased understanding of organofluorine cycling in aqueous and soil systems and understanding of PFAS outside of those quantifiable by modern LC-MS/MS techniques. This approach will also support Dynamic Work Planning, Triad, and other efficient approaches to site characterization utilizing field-based decision-making. (Anticipated Project Completion - 2023)

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