October 18, 2023 Webinar at-a-glance!

Dr. Diana Aga’s Talk: “Can we remove “forever” from forever chemicals?”

Abstract: Per- and polyfluoroalkyl substances (PFAS) have been called “Forever Chemicals” because of their high stability in the environment and resistance to degradation.  Scientists and engineers are racing to develop innovative ways to destroy PFAS using various approaches involving a combination of biological, chemical, and physical techniques.  In this presentation, recent advances to remove PFAS in wastewater and biosolids samples, two main sources of PFAS in the environment, will be discussed. The use of nanotechnology in combination with mixed bacterial culture from activated sludge systems provides promise in destroying PFAS from wastewater. Similarly, pyrolysis of biosolids also holds promise for PFAS destruction in sludge collected from water resource recovery facilities and other similar municipal plants. Ultimately, the goal is to remove “forever chemicals” in the environment, and show evidence that no toxic by-products are left behind, which can only be made possible through teamwork and collaborations between researchers from various disciplines.

Dr. Christopher Higgins’ Talk: “The complex challenges of poly- and perfluoroalkyl substances as environmental contaminants: A soil perspective” 

Abstract: The challenges posed by the widespread contamination of soils and groundwater by poly- and perfluoroalkyl substances (PFASs) are immense. Despite growing concerns about human exposure to perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS), other PFASs, particularly those derived from aqueous film-forming foams (AFFFs) have garnered little attention. Recent work using high resolution mass spectrometry (HRMS) has revealed that there are dozens, if not hundreds, of additional PFASs that may be associated with AFFF-impacted sites. Importantly, many of these newly discovered PFASs have diverse chemical structures, including anionic, cationic, and zwitterionic structures. Some of these PFASs clearly remain bound strongly to soil, while other AFFF-derived PFASs, including transformation products, likely migrate into AFFF-impacted drinking water. In this presentation, the complex challenges posed by PFASs for human and environmental risk will be presented and discussed. Particular attention will be given to the role of the anionic, cationic, and zwitterionic polyfluorinated substances at AFFF-impacted sites that can serve as precursors to the more persistent and mobile perfluoroalkyl acids (PFAAs).  Collectively, these data suggest a need for more thorough assessments of soils as potential long-term sources of PFAAs to groundwaters and surface waters.