Grantee Research Project Results
Final Report: Characterizing Residential PFAS Exposure Pathways among Children and Adults using Multimedia Measurements and Questionnaires
EPA Grant Number: CR840430Title: Characterizing Residential PFAS Exposure Pathways among Children and Adults using Multimedia Measurements and Questionnaires
Investigators:
Institution:
EPA Project Officer:
Project Period: July 1, 2022 through May 12, 2025
Project Amount: $250,000
RFA: COLLECTION OF CONCORDANT MULTIMEDIA MEASUREMENTS TO EVALUATE PFAS HUMAN EXPOSURE PATHWAYS (2021) RFA Text | Recipients Lists
Research Category: Children's Health , Urban Air Toxics , Endocrine Disruptors , Heavy Metal Contamination of Soil/Water , Human Health , Air , Safer Chemicals , PFAS Treatment
Objective:
The overarching goal of this study (PFAS HOME) is to better characterize important PFAS exposure pathways among vulnerable groups, especially children, in both communities with drinking water contamination and the general population. Our first objective was to characterize residential exposures to per- and polyfluoroalkyl substances (PFAS) by measuring volatile and semivolatile PFAS in air and dust in homes with children and adults. Our second objective was to evaluate associations between PFAS concentrations in air and dust and home characteristics, including flooring type and reported consumer product use. We measured concentrations of 83 volatile and semivolatile PFAS in indoor air and house dust samples collected in 52 homes with at least two participants—typically at least one child and one adult—from the Massachusetts (MA) PFAS and Your Health Study, one of seven ATSDR-funded Multi-Site Studies. We also collected information on residential and dietary exposures sources via questionnaire. Our long-term goal is to evaluate the association between PFAS levels in the home and PFAS blood levels among children and adults living in these homes.
Summary/Accomplishments (Outputs/Outcomes):
The PFAS-HOME study leverages Silent Spring Institute’s leadership in PFAS research and expertise in assessing indoor exposures, combined with Emory University’s cutting-edge PFAS analytical capabilities, to provide novel insights into the extent of PFAS exposures from sources within home environments. Although many consumer products and building materials are known to contain PFAS, the extent of exposures from these sources remains poorly understood. Indeed, recent assessments of PFAS exposures have called for additional research on exposure pathways other than contaminated drinking water, highlighting the need to study residential exposures. Findings from this study will enhance interpretation of biomonitoring data and improve understanding of the relative importance of different PFAS exposure sources, thereby informing effective exposure reduction strategies.
Preliminary Results
Within the 52 households enrolled in the PFAS HOME study, 91 adults and 37 children also participated in the MA PFAS and Your Health Study, which provided biomonitoring data, information on water consumption, residential and health histories, and anthropometric and effect biomarker data. By including both children and adults from the same household, we can assess potentially different exposure patterns that may be especially relevant for protecting children.
PFAS are ubiquitous in the indoor environment. Of the 83 targeted PFAS, 71 were detected in house dust and 72 in indoor air. On average, 29 PFAS were detected per dust sample and 20 per passive air sample. Sodium trifluoroacetate (TFA), hexafluoropropylene oxide dimer acid (HFPO-DA, also known as GenX), and sodium bis(1H,1H,2H,2H-perfluorooctyl) phosphate (6:2-diPAP) dominated house dust samples, comprising the largest percentage total PFAS in the samples. In air, the fluorotelomer alcohols (FTOHs) contributed the most to the total PFAS concentrations followed by the perfluoroalkyl sulfonamidoethanols (FBSEs).
Conclusions:
Outputs
• Exposure measurements (indoor air concentrations, household dust concentrations) for an extensive list of 83 PFAS target analytes and questionnaire data from 52 homes with corresponding biomonitoring data in the MA PFAS and Your Health Study. Our dataset represents one of the most comprehensive assessments of PFAS in dust and air and is unique in including both volatile and semivolatile compounds in both media.
• Development and evaluation of protocols and SOPs for collecting air and dust samples and measuring a targeted set of PFAS in the residential environment. Extensive questionnaire on potential indoor sources of PFAS based on current scientific literature. These protocols can be adapted by future studies to generate additional exposure data for priority pathways and newly recognized PFAS in home environments.
• Preliminary assessment of residential exposures, including relationships between measured indoor air and house dust concentrations and associations of these concentrations with housing characteristics and behaviors related to consumer products within the home. Identifying important predictors of exposure can inform exposure reduction strategies. We anticipate submitting a manuscript summarizing indoor air and dust PFAS concentrations and associations with housing characteristics and behaviors for peer-reviewed publication.
We anticipated providing total organofluorine (TOF) and extractable organofluorine (EOF) concentrations in the house dust samples. However, due to the early termination of this grant, we could not complete this analysis.
Outcomes
• Improved understanding of the relationship between PFAS levels in indoor air and house dust. While some prior studies have investigated these relationships for a limited set of long-chain PFAS, our study expanded knowledge of these relationships for a broader suite of PFAS, which is important for characterizing the extent of exposure from both ingestion and inhalation pathways and how their relative contributions vary across different types of PFAS.
• Greater understanding of the contribution of residential exposure pathways to overall PFAS exposures. Residential exposure pathways may be particularly important for vulnerable groups such as children and for the general population in areas less impacted by drinking water contamination. These pathways may also be particularly important for characterizing exposures to volatile PFAS and to short-chain and other current-use PFAS.
• Improved interpretation of PFAS biomonitoring data. Results could help to better interpret the results from biomonitoring programs funded at the federal and state levels.
With the results from the proposed TOF/EOF analysis, we anticipated greater understanding of the degree to which current targeted PFAS analyses may underestimate total PFAS in house dust. However, due to the early termination of this grant, we could not complete this analysis.
Supplemental Keywords:
exposure, risk assessment, children’s health, Massachusetts, PFASRelevant Websites:
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.