Per- and Polyfluoroalkyl Substance (PFAS)
Per- and Polyfluoroalkyl Substances (PFAS) describe a vast class of fluorinated synthetic chemicals which possess oil/water-repellant and surfactant properties in addition to high chemical and thermal stability. Because of these unique properties, PFAS are widely utilized in consumer products, ranging from cookware to cosmetics, and industrial applications, like fire-fighting foams and chrome plating processes. However, these same properties lend to PFAS persistence and harm to humans and the environment alike. Toxicological research on select PFAS over the last decade, like perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), has led to shifts in PFAS production, regulation, and management. However, many downstream sectors continue to face management challenges associated with PFAS-laden materials (i.e., municipal solid waste, contaminated soils, impacted pavements, wastewaters, and byproducts). The Sustainable Materials Management Research Laboratory, in collaboration with state and federal agencies, is working to address real-world PFAS management challenges faced by the solid waste sector. From the development of new methods for measuring emerging PFAS to the examination of PFAS fate in pavements through interdisciplinary approaches, our research team aims to answer knowledge gaps and provide actionable data for stakeholders, researchers, and policy makers alike.
Current Projects
- PFAS Leaching from Concrete Paved Surfaces (Strategic Environmental Research and Development Program): From the 1950s to 2010s, aqueous film forming foams (AFFF) containing PFAS were extensively used at military installations, airports, and fire-fighting training facilities. As the investigation into the fate and transport of PFAS broadens, we are examining a less explored avenue of PFAS release into the environment – contaminated pavement materials. Ongoing work characterizing the PFAS leaching behavior from field-collected and laboratory-simulated pavement materials will inform future risk assessments, management, and potential reuse scenarios for these impacted materials.
- Thermal Treatment of PFAS Contaminated Materials (Florida Department of Environmental Protection): PFAS impacted sites such as fire training facilities, military installations, and airports are faced with the challenge of disposing bulk quantities of contaminated soil, but the chemical and thermal stability of PFAS leaves questions regarding the treatment feasibility of PFAS within traditional incineration technologies. A “mass-balance” accounting for volatile products of incomplete combustion (PICs) has yet to be addressed regarding PFAS decomposition in thermal treatment processes; contaminated soils from across the state are being treated in a lab-scale system with full emissions characterization to address this gap and inform future materials management.
- PFAS Fate in Impacted Asphalt Pavement Recycling (National Asphalt Pavement Association): Asphalt pavement remains among the most heavily recycled materials in the US. Emerging concerns associated with PFAS contamination to asphalt pavements exposed to firefighting foams at military installations, airports, and fire-training facilities has raised questions regarding the fate of PFAS within common asphalt recycling practices. Utilizing field-collected and laboratory-generated pavements, we are working to examine PFAS leachability, volatility, and behavior through the various lifecycle stages of recycled asphalt pavements.
- Evaluating Solidification and Stabilization Technologies for PFAS-impacted Wastes (US Environmental Protection Agency): As state and federal guidelines/regulations evolve for PFAS management, concerns have emerged regarding the safe disposal of PFAS-concentrated waste streams like aqueous film forming foams (AFFFs), electroplating sludge, or contaminated wastewaters. While some of these waste streams are already managed as hazardous wastes due to concentrations of heavy metals, available technologies for stabilization/solidification of hazardous wastes have not been evaluated for their efficacy in PFAS encapsulation. To understand current PFAS management at hazardous waste landfills and inform the safe disposal of PFAS-concentrated waste streams in the future, the leachability and volatility of PFAS through stabilization/solidification technologies is being examined.
- Simulating PFAS Fate and Behavior through Municipal Solid Waste Landfill Reactors: In the landfill environment, PFAS from consumer wastes can migrate into landfill byproducts, leachate and gas, posing management challenges to operators. With waste decomposition, PFAS profiles and concentrations in leachate and gas may change, but the extent, relationships, and long-term trends within/between gas versus leachate byproducts is not well understood – impacting effective management of these chemicals at landfills. The fate and behavior of PFAS within landfill environments is being studied through simulated landfill reactors, monitoring PFAS releases to gas and leachate over time, to reveal PFAS behavior and inform future management efforts.