Presentation Type
Poster
Location
Walker Conference Center and Virtual
Room Number
Room A
Start Date
8-4-2025 12:00 AM
End Date
8-4-2025 12:00 AM
Abstract
Perfluoroalkane substances (PFAS) are a class of molecules characterized by strong carbon-fluorine bonds, low polarizability, and weak dispersion forces providing numerous industrial applications. Despite their utility, PFAS has been identified by the EPA as substances of significant concern due to their bioaccumulation in humans, animals, and environmental sources. PFAS has also recently been shown to induce a structural change on microplastics, another increasingly prevalent pollutant. The PFAS-induced structural change is hypothesized to cause significant mixture effects, altering the fate and transport properties, toxicity, and associated health risks for pollutant PFAS’s. To investigate these mixture effects, we utilize aaMD simulations of polyethylene dimer (hexane) mixed with perfluorohexane at concentrations of 0%, 25%, 50%, 75%, and 100%. In agreement with prior studies, our results demonstrate the OPLS force field does not accurately describe the conformational change observed experimentally for hexane. Additional simulations were conducted using modified hydrogen—fluorine LJ potentials, demonstrating an increase in the experimentally observed twist conformation after reducing the LJ parameter by 25%.
Keywords
Perfluoroalkane substances, Microplastics, Molecular Dynamics, Mixture Effects
Characterizing the Mixture Effects of Perfluorinated Alkane Systems (PFAS) with Microplastics from an All-Atom Molecular Dynamics Simulation
Walker Conference Center and Virtual
Perfluoroalkane substances (PFAS) are a class of molecules characterized by strong carbon-fluorine bonds, low polarizability, and weak dispersion forces providing numerous industrial applications. Despite their utility, PFAS has been identified by the EPA as substances of significant concern due to their bioaccumulation in humans, animals, and environmental sources. PFAS has also recently been shown to induce a structural change on microplastics, another increasingly prevalent pollutant. The PFAS-induced structural change is hypothesized to cause significant mixture effects, altering the fate and transport properties, toxicity, and associated health risks for pollutant PFAS’s. To investigate these mixture effects, we utilize aaMD simulations of polyethylene dimer (hexane) mixed with perfluorohexane at concentrations of 0%, 25%, 50%, 75%, and 100%. In agreement with prior studies, our results demonstrate the OPLS force field does not accurately describe the conformational change observed experimentally for hexane. Additional simulations were conducted using modified hydrogen—fluorine LJ potentials, demonstrating an increase in the experimentally observed twist conformation after reducing the LJ parameter by 25%.