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At least 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Rapid and Ultrasensitive Short-Chain PFAS (GenX) Detection in Water via Surface-Enhanced Raman Spectroscopy with a Hierarchical Nanofibrous Substrate

GenX, the trade name of hexafluoropropylene oxide dimer acid (HFPO-DA) and its ammonium salt, is a short-chain PFAS that has emerged as a substitute for the legacy PFAS perfluorooctanoic acid (PFOA). However, GenX has turned out to be more toxic than people originally thought. In order to monitor and regulate water quality according to recently issued drinking water standards for GenX, rapid and ultrasensitive detection of GenX is urgently needed. For the first time, this study reports ultrasensitive (as low as 1 part per billion (ppb)) and fast detection (in minutes) of GenX in water via surface-enhanced Raman spectroscopy (SERS) using a hierarchical nanofibrous SERS substrate, which was prepared by assembling ~60 nm Ag nanoparticles on electrospun nylon-6 nanofibers through a “hot start” method. The findings in this research highlight the potential of the engineered hierarchical nanofibrous SERS substrate for enhanced detection of short-chain PFASs in water, contributing to the improvement of environmental monitoring and management strategies for PFASs.

Ismail, Ali K. (ORCID:0009000005987973)↗
NASA NTRS2022

Hydrocarbon Burn Facility, SWMU 007 PER- and Polyfluoroalkyl Substances (PFAS) Assessment report Addendum Kennedy Space Center, Florida

This document discusses the Per-and Polyfluoroalkyl Substances (PFAS) assessment activities performed from December 2020 through November 2021 at the Hydrocarbon Burn Facility (HBF) located at Kennedy Space Center (KSC), Florida. The HBF site has been designated Solid Waste Management Unit (SWMU) 007 under KSC’s Resource Conservation and Recovery Act (RCRA) Corrective Action Program. This PFAS Assessment Report Addendum (ARA) was prepared by Tetra Tech, Inc., for the National Aeronautics and Space Administration (NASA) under Indefinite Delivery Indefinite Quantity (IDIQ) Contract 80KSC019D0011-80KSC019F0077.

Jennifer M. Buel↗
NASA NTRS2023

Contractor Support Building #7 Per- and Polyfluoroalkyl Substances (PFAS) Site Assessment Work Plan

This Work Plan documents the proposed field sampling activities for a per- and polyfluoroalkyl substances (PFAS) Site Assessment at the Contractor Support Building (CSB) #7 at Kennedy Space Center (KSC). The Work Plan provides a background of the historical activities that occurred at CSB #7, and the limited environmental investigations performed at CSB #7. The proposed Site Assessment activities at CSB #7 include the advancement of a soil lithologic boring to 60 feet below ground surface, the installation of a staff gauge in site surface water, perform direct push groundwater sampling at eight locations, and collect four surface water samples. Sampling details, depths, and locations are presented in the Work Plan. The Work Plan was presented to the KSC Remediation Team in the form of an Advance Data Package in February 2023. Following STRIVES approval, the CSB #7 PFAS Site Assessment Work Plan will be formally submitted to the Florida Department of Environmental Protection.

Howard Franklin Fowler↗
NASA NTRS2023

Former SLF Fire and Rescue Building SWMU #120 Per- and Polyfluoroalkyl Substances (PFAS) Site Assessment Work Plan

This Work Plan documents the proposed field sampling activities for a per- and polyfluoroalkyl substances (PFAS) Site Assessment at the Former Space Shuttle Landing Facility (SLF) Fire and Rescue Building (FRB) at Kennedy Space Center (KSC). The Work Plan provides a background of the historical activities that occurred at the SLF FRB, and the limited environmental investigations performed at the SLF FRB. The proposed Site Assessment activities at SLF FRB includes the collection of soil samples from eight locations, the advancement of a soil lithologic boring to 60 feet below ground surface, the installation of a staff gauge in site surface water, the installation of four monitoring wells, perform direct push groundwater sampling at seven locations, and collect one surface water sample. Sampling details, depths, and locations are presented in the Work Plan. The Work Plan was presented to the KSC Remediation Team in the form of an Advance Data Package in February 2023. Following STRIVES approval, the SLF FRB PFAS Site Assessment Work Plan will be formally submitted to the Florida Department of Environmental Protection.

Howard Franklin Fowler↗
NASA NTRS2023

Morpheus Test Area SWMU #119 Per- and Polyfluoroalkyl Substances (PFAS) Site Assessment Work Plan

This Work Plan documents the proposed field sampling activities for a per- and polyfluoroalkyl substances (PFAS) Site Assessment at the Morpheus Test Area (MTA) at Kennedy Space Center (KSC). The Work Plan provides a background of the historical activities that occurred at the MTA, and the limited environmental investigations performed at the MTA. The proposed Site Assessment activities at MTA includes the collection of soil samples from seven locations, the installation of a staff gauge in site surface water, the installation of four monitoring wells, perform direct push groundwater sampling at ten locations, and collect one surface water sample. Sampling details, depths, and locations are presented in the Work Plan. The Work Plan was presented to the KSC Remediation Team in the form of an Advance Data Package in February 2023. Following STRIVES approval, the SLF FRB PFAS Site Assessment Work Plan will be formally submitted to the Florida Department of Environmental Protection.

Howard Franklin Fowler↗
DOE OSTI2023

An infrared spectral database for gas-phase quantitation of volatile per- and polyfluoroalkyl substances (PFAS)

We report the construction of a database of vetted infrared spectra specifically targeting volatile fluorocarbon gases that may be emitted during thermal treatment of per- and polyfluoroalkyl substances (PFAS) to assist understanding of treatment processes and improve quantification. To populate this database, protocols derived from the Pacific Northwest National Laboratory (PNNL) infrared spectral database are used, curtailing the species selection for this data set. Each spectrum in the database is a weighted average derived from 10 or more individual measurements at different partial pressures (static method) or flow rates (dissemination method) to yield good fidelity of both strong and weak infrared signatures, with each composite spectrum ranging from = 6500 cm-1 to = 600 cm-1 with an apodized resolution of 0.112 cm-1. This resolution was chosen to fully resolve all spectral features, recognizing that atmospheric pressure broadening results in nearly all ro-vibrational lines having linewidths = 0.1 cm-1. As an example case, application of the database is demonstrated via identification and quantification of dominant 1H-perfluoroheptane and perfluorohept-1-ene fluorocarbon products resulting from thermal decomposition of perfluorooctanoate (PFOA) below 450 °C.

Infrared, Gas-phase spectra, FTIR, Spectral databa↗
NASA NTRS2020

Predictive Integrated Stratigraphic Modeling (PRISM®) Work Plan Center Wide Per- and Polyfluoroalkyl Substances (PFAS) Potential Release Location (PRL) 237 Kennedy Space Center, Florida

This document presents a description of various site investigation activities that will be used to improve the conceptual site model (CSM) at the Kennedy Space Center (KSC) to develop a better understanding of the fate and transport of per- and polyfluoroalkyl substances (PFAS) in groundwater and surface water. The activities proposed herein include three primary tasks: a sequence stratigraphic analysis, groundwater and surface water gauging and sampling, and a stormwater pollutant modeling analysis.

PFAS↗
DOE OSTI2025

Integrating Contaminant Source Indicators, Water Quality Measures, and Ecotoxicity to Characterize Contaminant Mixtures and Per- and Polyfluoroalkyl Substance (PFAS) Variability in an Urban Watershed

Thousands of chemical contaminants threaten watersheds but are time and cost prohibitive to monitor. Identifying their sources, transport, and ecological risk is limited in heterogeneous urban watersheds. We present an integrative watershed approach using source-specific indicator compounds, common water quality measures, and ecotoxicity assays to examine the distribution of contaminant mixtures in an urbanized watershed. Indicator compound concentrations were temporally and spatially distributed for treated/untreated sewage (sucralose, artificial sweetener), road runoff (diphenyl-guanidine [DPG] and 6PPD-quinone [6PPD-Q], automobile tire additives), and lawncare runoff (aminomethanephosphonic acid (AMPA), major degradant of the herbicide glyphosate). Sucralose was predominately sourced from treated wastewater; measurable concentrations in tributaries indicated raw sewage inputs. DPG and 6PPD-Q concentrations correlated to road density during base flow and were elevated during stormflow. AMPA was measurable spring through fall, especially where lawns were dense. When specific sources dominated flow, water quality measures correlated with wastewater (sulfate, potassium, chloride, and sodium) and road runoff (chromium and lead) indicators. The limited behavioral toxicity observed in exposed zebrafish (Danio rerio) (18%) was not well explained by source-indicators. PFAS concentrations were highly variable spatially but not well explained by our source-specific indicator compounds. Here, more costly compound-specific monitoring may be necessary when multiple sources exist or when unexpected toxicity trends occur.

computer simulations↗
DOE OSTI2022

An e-beam irradiation beamline at Jefferson Lab for 1,4-dioxane and per- and polyfluoroalkyl substances (PFAS) remediation in wastewater

The Upgraded Injector Test Facility (UITF) at Jefferson Lab, providing a beam energy up to 10 MeV, is suitable for wastewater remediation research. To investigate the degradation of 1,4-dioxane and per- and polyfluoroalkyl substances (PFAS), widespread in wastewater and potential to be regulated in near future, a beamline for electron-beam irradiation has been designed, installed and successfully commissioned at the UITF. A solenoid with a peak axial magnetic field of up to 0.28 T and a raster were used to obtain a Gaussian beam profile with a transverse standard deviation of 15 mm. It was applied to irradiate 1,4-dioxane sample filled in the target cell that was designed to let the entire sample receive significant irradiation doses. The dose distribution and absorbed dose, few studied in the current publications, are necessary measures for the degradation mechanism investigation and have been innovatively achieved in this work using simulations which were calibrated with opti-chromic dosimeter rods directly exposed to the electron beam. This approach provides an important way for investigating the environmental remediation impact of electron-beam irradiation.

Li, Xi↗
DOE OSTI2022

USING E-BEAM IRRADIATION BEAMLINE AT JEFFERSON LAB TO REMOVE 1,4-DIOXANE AND PFAS IN WASTEWATER

The designed e-beam irradiation beamline [1] at Jefferson Lab has been commissioned and applied to study the degradation removal of 1,4-dioxane and per- and polyfluoroalkyl substances (PFAS) in wastewater by collaborating with Hampton Roads Sanitation District (HRSD), treating wastewater in southeast Virginia. The absorbed dose and dose distribution in the entire sample were achieved innovatively using Monte-Carlo simulations that were calibrated with opti-chromic dosimeter rods directly exposed to the e-beam. This research could be a stepstone to the future MW compact SRF accelerator [2] for wastewater remediation.

Li, X.↗
DOE OSTI2023

Dose Response, Dosimetric, and Metabolic Evaluations of Replacement PFAS Perfluoro-(2,5,8-trimethyl-3,6,9-trioxadodecanoic) Acid (HFPO-TeA)

Few studies are available on the environmental and toxicological effects of perfluoroalkyl ether carboxylic acids (PFECAs), such as GenX, which are replacing legacy PFAS in manufacturing processes. To collect initial data on the toxicity and toxicokinetics of a longer-chain PFECA, male and female Sprague Dawley rats were exposed to perfluoro-(2,5,8-trimethyl-3,6,9-trioxadodecanoic) acid (HFPO-TeA) by oral gavage for five days over multiple dose levels (0.3–335.2 mg/kg/day). Clinically, we observed mortality at doses >17 mg/kg/day and body weight changes at doses ≤ 17 mg/kg/day. For the 17 mg/kg/day dose level, T3 and T4 thyroid hormone concentrations were significantly decreased (p < 0.05) from controls and HFPO-TeA plasma concentrations were significantly different between sexes. Non-targeted analysis of plasma and in vitro hepatocyte assay extractions revealed the presence of another GenX oligomer, perfluoro-(2,5-dimethyl-3,6-dioxanonanoic) acid (HFPO-TA). In vitro to in vivo extrapolation (IVIVE) parameterized with in vitro toxicokinetic data predicted steady-state blood concentrations that were within seven-fold of those observed in the in vivo study, demonstrating reasonable predictivity. The evidence of thyroid hormone dysregulation, sex-based differences in clinical results and dosimetry, and IVIVE predictions presented here suggest that the replacement PFECA HFPO-TeA induces a complex and toxic exposure response in rodents.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS2024

Base Support Building and Kennedy Athletic, Recreation, and Social Park II, SWMU 014 and SWMU 118 PFAS 2023 Site Assessment Progress Report, Kennedy Space Center, Florida

This Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS) 2023 Site Assessment Progress Report presents the findings from the 2023 investigation activities, completed between October 12, 2022, and January 24, 2024, at the Base Support Building, Solid Waste Management Unit (SWMU) 014 and at the Kennedy Athletic, Recreation, and Social (KARS) Park II SWMU 118 located within Kennedy Space Center, Florida.

Richard G Smith↗