Understanding prenatal household exposures to per- and polyfluorylalkyl substances using paired Biological and dust measurements with sociodemographic and housing variables.

Per- and poly-fluoroalkyl substances (PFAS) are chemicals of concern-they are ubiquitous, persistent, with known and suspected health impacts. Well studied, primary sources of exposure to PFAS are drinking water and food. The presence of PFAS in human tissue of general populations suggests other important exposure sources/pathways.

Quantifying EDC Emissions from Consumer Products: A Novel Rapid Method and Its Application for Systematic Evaluation of Health Impacts.

Endocrine-disrupting chemicals (EDCs) are widely used in consumer products and have been associated with adverse public health outcomes and significant economic costs. We developed a rapid chamber method for measuring EDC emissions from consumer products, significantly reducing the time to reach steady state from weeks or months to minutes or hours. Using this method, we quantified EDC emissions from a wide range of products, determined the emission-control parameters, and established their relationship with the EDC content () and physicochemical properties.

Environmental public health research at the U.S. Environmental Protection Agency: A blueprint for exposure science in a connected world.

Exposure science plays an essential role in the U.S. Environmental Protection Agency's (U.

Exposure to per- and polyfluoroalkyl substances (PFAS) in North Carolina homes: results from the indoor PFAS assessment (IPA) campaign.

Per and polyfluoroalkyl substances (PFAS) are ubiquitous in the indoor environment, resulting in indoor exposure. However, a dearth of concurrent indoor multi-compartment PFAS measurements, including air, has limited our understanding of the contributions of each exposure pathway to residential PFAS exposure. As part of the Indoor PFAS Assessment (IPA) Campaign, we measured 35 neutral and ionic PFAS in air, settled dust, drinking water, clothing, and on surfaces in 11 North Carolina homes.

Indoor air concentrations of PM quartz fiber filter-collected ionic PFAS and emissions to outdoor air: findings from the IPA campaign.

Per- and polyfluoroalkyl substances (PFAS) are prevalent in consumer products used indoors. However, few measurements of ionic PFAS exist for indoor air. We analyzed samples collected on PM quartz fiber filters (QFFs) in 11 North Carolina homes 1-3 times in living rooms (two QFFs in series), and immediately outside each home (single QFF), for 26 ionic PFAS as part of the 9 months Indoor PFAS Assessment (IPA) Campaign.

Linking exposure to per- and polyfluoroalkyl substances (PFAS) in house dust and biomonitoring data in eight impacted communities.

Per- and polyfluoroalkyl substances (PFAS) are widely used in industry and have been linked to various adverse health effects. Communities adjacent to sites where PFAS are manufactured, stored, or used may be at elevated risk. In these impacted communities, significant exposure often occurs through contaminated drinking water, yet less is known about the role of other pathways such as residential exposure through house dust.

Systematic evidence mapping of potential correlates of exposure for per- and poly-fluoroalkyl substances (PFAS) based on measured occurrence in biomatrices and surveys of dietary consumption and product use.

Per- and poly-fluoroalkyl substances (PFAS) are widely observed in environmental media and often are found in indoor environments as well as personal-care and consumer products. Humans may be exposed through water, food, indoor dust, air, and the use of PFAS-containing products. Information about relationships between PFAS exposure sources and pathways and the amounts found in human biomatrices can inform source-contribution assessments and provide targets for exposure reduction.

Modeling clothing as a secondary source of exposure to SVOCs across indoor microenvironments.

Background: Evidence suggests that clothing can influence human exposure to semi-volatile organic compounds (SVOCs) through transdermal uptake and inhalation.

Objectives: The objectives of this study were [1] to investigate the potential for clothing to function as a transport vector and secondary source of gas-phase SVOCs across indoor microenvironments, [2] to elucidate how clothing storage, wear, and laundering can influence the dynamics of transdermal uptake, and [3] to assess the potential for multiple human occupants to influence the multimedia dynamics of SVOCs indoors.

Methods: A computational modeling framework (ABICAM) was expanded, applied, and evaluated by simulating and augmenting two "real-world" chamber experiments.

Cloth-Air Partitioning of Neutral Per- and Polyfluoroalkyl Substances (PFAS) in North Carolina Homes during the Indoor PFAS Assessment (IPA) Campaign.

Partitioning of per- and polyfluoroalkyl substances (PFAS) to indoor materials, including clothing, may prolong the residence time of PFAS indoors and contribute to exposure. During the Indoor PFAS Assessment (IPA) Campaign, we measured concentrations of nine neutral PFAS in air and cotton cloth in 11 homes in North Carolina, for up to 9 months. Fluorotelomer alcohols (i.

Using Geospatial Data and Random Forest To Predict PFAS Contamination in Fish Tissue in the Columbia River Basin, United States.

Decision makers in the Columbia River Basin (CRB) are currently challenged with identifying and characterizing the extent of per- and polyfluoroalkyl substances (PFAS) contamination and human exposure to PFAS. This work aims to develop and pilot a methodology to help decision makers target and prioritize sampling investigations and identify contaminated natural resources. Here we use random forest models to predict ∑PFAS in fish tissue; understanding PFAS levels in fish is particularly important in the CRB because fish can be a major component of tribal and indigenous people diet.

Systematic Evidence Mapping of Potential Exposure Pathways for Per- and Polyfluoroalkyl Substances Based on Measured Occurrence in Multiple Media.

Given that human biomonitoring surveys show per- and polyfluoroalkyl substances (PFAS) to be ubiquitous, humans can be exposed to PFAS through various sources, including drinking water, food, and indoor environmental media. Data on the nature and level of PFAS in residential environments are required to identify important pathways for human exposure. This work investigated important pathways of exposure to PFAS by reviewing, curating, and mapping evidence for the measured occurrence of PFAS in exposure media.

Geographic and demographic variability in serum PFAS concentrations for pregnant women in the United States.

Background: While major pathways of human PFAS exposure are thought to be drinking water and diet, other pathways and sources have also been shown to contribute to a person's cumulative exposure. However, the degree of contribution of these other sources to PFAS body burdens is still not well understood and occurrence data for PFAS in conssumer products and household materials are sparse. Questionnaire data concordant with biomonitoring may improve understanding of associations between other PFAS exposure pathways and exposure in human populations.

Simulating patterns of life: More representative time-activity patterns that account for context.

Background: Complex contributions of environment to health are intimately connected to human behavior. Modeling of human behaviors and their influences helps inform important policy decisions related to critical environmental and public health challenges. A typical approach to human behavior modeling involves generating daily schedules based on time-activity patterns of individual humans, simulating 'agents' with these schedules, and interpreting patterns of life that emerge from the simulation to inform a research question.

Modeling Clothing as a Vector for Transporting Airborne Particles and Pathogens across Indoor Microenvironments.

Evidence suggests that human exposure to airborne particles and associated contaminants, including respiratory pathogens, can persist beyond a single microenvironment. By accumulating such contaminants from air, clothing may function as a transport vector and source of "secondary exposure". To investigate this function, a novel microenvironmental exposure modeling framework (ABICAM) was developed.

Assessment of Non-Occupational 1,4-Dioxane Exposure Pathways from Drinking Water and Product Use.

1,4-Dioxane is a persistent and mobile organic chemical that has been found by the United States Environmental Protection Agency (USEPA) to be an unreasonable risk to human health in some occupational contexts. 1,4-Dioxane is released into the environment as industrial waste and occurs in some personal-care products as an unintended byproduct. However, limited exposure assessments have been conducted outside of an occupational context.

Human exposure pathways to poly- and perfluoroalkyl substances (PFAS) from indoor media: A systematic review.

Background: Human exposure to per- and polyfluoroalkyl substances (PFAS) has been primarily attributed to contaminated food and drinking water. There is information indicating other sources and pathways of exposure in residential environments, but few studies report relationships between these indoor media and human biomonitoring measurements.

Methods: This study adapts existing systematic review tools and methodologies to synthesize evidence for PFAS exposure pathways from indoor environment media including consumer products, household articles, cleaning products, personal care products, and indoor air and dust.

Textile Washing Conveys SVOCs from Indoors to Outdoors: Application and Evaluation of a Residential Multimedia Model.

Indoor environments have elevated concentrations of numerous semivolatile organic compounds (SVOCs). Textiles provide a large surface area for accumulating SVOCs, which can be transported to outdoors through washing. A multimedia model was developed to estimate advective transport rates (fluxes) of 14 SVOCs from indoors to outdoors by textile washing, ventilation, and dust removal/disposal.

A state-of-the-science review of polychlorinated biphenyl exposures at background levels: relative contributions of exposure routes.

Exposure to polychlorinated biphenyls (PCBs) can occur through multiple routes and sources, including dietary intake, inhalation, dermal contact, and ingestion of dust and soils. Dietary exposure to PCBs is often considered the primary exposure route for the general population; however, recent studies suggest an increasing contribution from indoor inhalation exposure. Here, we aim to estimate the relative contribution of different PCB exposure pathways for the general population, as well as for select age groups.

Improving the quality of toxicology and environmental health systematic reviews: What journal editors can do.

Systematic reviews are fast increasing in prevalence in the toxicology and environmental health literature. However, how well these complex research projects are being conducted and reported is unclear. Since editors have an essential role in ensuring the scientific quality of manuscripts being published in their journals, a workshop was convened where editors, systematic review practitioners, and research quality control experts could discuss what editors can do to ensure the systematic reviews they publish are of sufficient scientific quality.

Human exposure pathways to poly- and perfluoroalkyl substances (PFAS) from indoor media: A systematic review protocol.

Background: Human exposure to per- and polyfluoroalkyl substances (PFAS) has been primarily attributed to contaminated food and drinking water. However, additional PFAS exposure pathways have been raised by a limited number of studies reporting correlations between commercial and industrial products and PFAS levels in human media and biomonitoring. Systematic review (SR) methodologies have been widely used to evaluate similar questions using an unbiased approach in the fields of clinical medicine, epidemiology, and toxicology, but the deployment in exposure science is ongoing.

Children's Environmental Health: A Systems Approach for Anticipating Impacts from Chemicals.

Increasing numbers of chemicals are on the market and present in consumer products. Emerging evidence on the relationship between environmental contributions and prevalent diseases suggests associations between early-life exposure to manufactured chemicals and a wide range of children's health outcomes. Using current assessment methodologies, public health and chemical management decisionmakers face challenges in evaluating and anticipating the potential impacts of exposure to chemicals on children's health in the broader context of their physical (built and natural) and social environments.

Transient Multimedia Model for Investigating the Influence of Indoor Human Activities on Exposure to SVOCs.

Empirical evidence suggests that human occupants indoors, through their presence and activities, can influence the dynamics of semivolatile organic compounds (SVOCs). To better understand these dynamics, a transient multimedia human exposure model was developed (Activity-Based Indoor Chemical Assessment Model (ABICAM)). This model parametrizes mass-balance equations as functions of time-dependent human activities.

Advancing systematic-review methodology in exposure science for environmental health decision making.

Systematic review (SR) is a rigorous methodology applied to synthesize and evaluate a body of scientific evidence to answer a research or policy question. Effective use of systematic-review methodology enables use of research evidence by decision makers. In addition, as reliance on systematic reviews increases, the required standards for quality of evidence enhances the policy relevance of research.

Enhancing life cycle chemical exposure assessment through ontology modeling.

In its 2014 report, A Framework Guide for the Selection of Chemical Alternatives, the National Academy of Sciences placed increased emphasis on comparative exposure assessment throughout the life cycle (i.e., from manufacturing to end-of-life) of a chemical.