Science Inventory

Relationships between Per- and Polyfluoroalkyl Substances (PFAS) and Physical-Chemical Parameters in Aqueous Landfill Samples

Citation:

Zhang, H., Y. Chen, Y. Liu, J. Bowden, T. Tolaymat, T. Townsend, AND H. Solo-Gabriele. Relationships between Per- and Polyfluoroalkyl Substances (PFAS) and Physical-Chemical Parameters in Aqueous Landfill Samples. CHEMOSPHERE. Elsevier Science Ltd, New York, NY, 329:138541, (2023). https://doi.org/10.1016/j.chemosphere.2023.138541

Impact/Purpose:

Investigating expected levels of per- and polyfluoroalkyl substances (PFAS) at landfills is often confounded by variable chemistries present with different aqueous sample types. The objective of the current study was to evaluate relationships between the physical-chemical properties which included bulk measurements, oxygen demanding components, and metals, and PFAS concentrations in different types of landfill aqueous. Aqueous landfill samples were collected and evaluated from 39 landfill facilities in Florida, United States. The samples evaluated included leachates from landfills that receive different waste types, and included municipal solid waste incineration (MSWA) ash, construction and demolition debris (C&D), and municipal solid waste (MSW), as well treated landfill leachate, gas condensate, storm water and groundwater from within and near the landfill boundaries. Results showed significant correlations between PFAS and alkalinity, total organic carbon (TOC), and ammonia for all leachate types. Other physical-chemical parameters that were significantly correlated with PFAS included specific conductivity, chemical oxygen demand (COD), and to a lesser extent, total dissolved solids (TDS) and total solids (TS). For gas condensates, PFAS was significantly correlated with TOC. Stormwater and groundwater, within and near the landfill boundaries, had considerably lower levels of PFAS and had mimimal correlation between PFAS and physical-chemical parameters. Although PFAS concentration and physical-chemical parameters and their correlations varied between different types of aqueous landfill samples, results suggest that physical-chemical properties may be useful as indicators of relative PFAS concentrations within a leachate type. More research is needed to validate the mechanisms that relate physical-chemical parameters to PFAS concentrations in landfill leachates.

Description:

Investigating expected levels of per- and polyfluoroalkyl substances (PFAS) at landfills is often confounded by variable chemistries present with different aqueous sample types. The objective of the current study was to evaluate relationships between the physical-chemical properties, which included bulk measurements, oxygen demanding components, metals, and PFAS concentrations in different types of landfill aqueous. Aqueous landfill samples were collected and evaluated from 39 landfill facilities in Florida, United States. The samples evaluated included leachates from landfills that receive different waste types and included municipal solid waste incineration (MSWA) ash, construction and demolition debris (C&D), and municipal solid waste (MSW), as well as treated landfill leachate, gas condensate, stormwater and groundwater from within and near the landfill boundaries. Results showed significant correlations between PFAS and alkalinity, total organic carbon (TOC), and ammonia for all leachate types. Other physical-chemical parameters that were significantly correlated with PFAS included specific conductivity, chemical oxygen demand (COD), and to a lesser extent, total dissolved solids (TDS) and total solids (TS). For gas condensates, PFAS was significantly correlated with TOC. Stormwater and groundwater within and near the landfill boundaries had considerably lower levels of PFAS and had a minimal correlation between PFAS and physical-chemical parameters. Although PFAS concentration and physical-chemical parameters and their correlations varied between different types of aqueous landfill samples, results suggest that physical-chemical properties may be useful as indicators of relative PFAS concentrations within a leachate type. More research is needed to validate the mechanisms that relate physical-chemical parameters to PFAS concentrations in landfill leachates.