Relationships between per- and polyfluoroalkyl substances (PFAS) and physical-chemical parameters in aqueous landfill samples. (July 2023)

• Record Type: Journal Article
• Authors: Zhang, Hekai; Chen, Yutao; Liu, Yalan; Bowden, John A.; Tolaymat, Thabet M.; Townsend, Timothy G.; Solo-Gabriele, Helena M.
• Is Part Of: Chemosphere. Volume 329(2023)
• Publication Date: 2023-07
• Subjects: Landfill leachate -- PFAS -- Physical-chemical parameters -- Correlation -- Alkalinity -- TOC; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2023.138541
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Variable chemistries of liquids from landfills can potentially impact levels of per- and polyfluoroalkyl substances (PFAS). The objective of the current study was to evaluate relationships between physical-chemical properties (bulk measurements, oxygen demand components, and metals) and PFAS concentrations in different types of aqueous landfill samples. Aqueous landfill samples were collected from 39 landfill facilities in Florida, United States. These samples included leachates from landfills that receive different waste types, such as municipal solid waste incineration ash (MSWA), construction and demolition debris (C&D), and municipal solid waste (MSW). Additional aqueous landfill samples were sourced from treated landfill leachate, gas condensate, stormwater, and groundwater from within and near the landfill boundaries. Results showed significant correlations (p < 0.05) between ∑26 PFAS and alkalinity (rs = 0.83), total organic carbon (TOC) (rs = 0.84), and ammonia (rs = 0.79) for all leachate types. Other physical-chemical parameters that were significantly correlated (rs > 0.60, p < 0.05) 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 concentrations and physical-chemical parameters and their correlations varied between different types of aqueous landfill samples, results suggest that physical-chemical properties can be useful 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. Graphical abstract: Image 1 Highlights: Aqueous samples from 39 landfill facilities in Florida were evaluated. PFAS and 35 physical-chemical parameters were analyzed. Alkalinity, TOC, and ammonia were correlated with PFAS. Some associations were dependent on leachate type. Associations may be due to dilution and chemical precipitation when released.