Grantee Research Project Results
2023 Progress Report: Multimedia Measurement of PFAS in the Residential Environment: Evaluating Human Exposure Pathways
EPA Grant Number: CR840428Title: Multimedia Measurement of PFAS in the Residential Environment: Evaluating Human Exposure Pathways
Investigators: Hoffman, Kate , Bartell, Scott M. , Stapleton, Heather , Peaslee, Graham , Vieira, Veronica
Institution: Duke University , University of Notre Dame , University of California - Irvine
EPA Project Officer: Barrow, Flora
Project Period: July 1, 2022 through June 30, 2024
Project Period Covered by this Report: July 1, 2022 through June 30,2023
Project Amount: $248,180
RFA: COLLECTION OF CONCORDANT MULTIMEDIA MEASUREMENTS TO EVALUATE PFAS HUMAN EXPOSURE PATHWAYS (2021) RFA Text | Recipients Lists
Research Category: Air , Drinking Water , Endocrine Disruptors , Environment , Heavy Metal Contamination of Soil/Water , Human Health , PFAS Treatment , Urban Air Toxics
Objective:
Widespread exposure to per- and polyfluoroalkyl substances (PFAS) has been documented in the US population. Considerable research has identified drinking water as a significant source of PFAS exposure, particularly in areas proximal to contaminated sites. However, recent data also link exposure with the indoor environment. PFAS are commonly detected in indoor air and dust, suggesting these exposure pathways may be particularly relevant for the general population. However, investigations of exposure via the indoor environment are limited. This study aims to address this data gap by evaluating PFAS in the residential environment and estimating its contribution to total PFAS exposure in the general population. We proposed to 1) Characterize total organic fluorine (TOF) in indoor air and dust, evaluating variation within the home and potential PFAS sources (e.g., carpet and textiles) and 2) Assess the relative contributions of PFAS measured in drinking water and the indoor environment in determining human PFAS exposure.
Approach: We partnered with the UCI PFAS Health Study, a CDC/ATSRD Multi-site Study cohort based in Orange County, California, to efficiently and rigorously address our aims. Collection of blood and urine from UCI PFAS Health Study participants is underway and drinking water wells in the study area have been tested for PFAS quarterly since 2019. We proposed to complement these existing data sources with additional collection of paired passive indoor air samples (3 per home) and dust samples (3 per home) from 50 participants’ homes. Participants will also wear a silicone wristband for 7 days to capture exposure across multiple microenvironments. Samples will be evaluated for PFAS as well as TOF, a marker of PFAS. Variation in TOF within a home will be assessed statistically and evaluated in relation to products present in the home. We will identify the relative importance of drinking water, diet, and indoor exposure routes (air and dust) in determining PFAS body burdens, investigating the relationship between each matrix and serum.
Expected Outcomes: Successful completion of our aims will address key questions on the most relevant PFAS exposure pathways for the general US population. Specifically, we will determine how much variability in PFAS serum levels in this study population is explained by water consumption and residential sources and will assess variation due to other sources (e.g., diet and product use), which is a critical first step in designing exposure reduction strategies and policies. In addition, we will evaluate the minimal set of measurements that can be implemented to classify individual exposure levels and determine whether silicone wristbands are sufficient to capture residential exposure information needed to estimate PFAS exposure. Advances in exposure assessment have important implications for identifying vulnerable populations and efficiently evaluating exposure for future health impacts studies.
Progress Summary:
During this project period, our team has focused on regulatory requirements for data collection and sharing, as well as human subjects protections. We have instituted measures to ensure the robust data collection and efforts to enhance reproducibility and future data sharing opportunities. In addition, analysis of existing samples which complement this work is being conducted to provide additional insights into the relationship between indoor PFAS sources and human exposure.
Future Activities:
Study activities for the upcoming project year will focus on data and sample collection as well as sample analysis. We anticipate completing 50 home visits and sampling events during the next project period and will analyze samples for PFAS and TOF during this period.
Supplemental Keywords:
Air, Dust, Silicone Wristbands, Human Exposure, poly- and perfluoroalkyl substances (PFAS), Total Fluorine (TOF)The 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.