Download or read book Human Exposure to Polybrominated Diphenyl Ethers PBDES in the Indoor Environment written by Deborah Jean Watkins and published by . This book was released on 2011 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Polybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardants that have been widely added to consumer products such as polyurethane foam furniture and electronics. Exposure to PBDEs has been associated with adverse effects on neurodevelopment and the endocrine system. House dust and diet are thought to be main sources of PBDE exposure, but the process by which these compounds are released from products and subsequently enter people is somewhat unclear. In addition, PBDE exposure in offices and vehicles has not been well characterized. The objectives of this work were to examine pathways of PBDE exposure in multiple indoor microenvironments among a population of 31 office workers. Associations between concurrent measures of PBDEs in office dust, air, and surface wipes, home dust, vehicle dust, handwipes, and serum were examined. Dietary exposure to PBDEs was also explored using a food frequency questionnaire. In Chapter 2 we report positive correlations between PBDEs in office air, dust, and surface wipes. Associations between the three samples types were influenced by the volatility of individual congeners, as well as characteristics of the surrounding environment. PentaBDEs in handwipes were equally correlated with office air, dust, and surface wipes, suggesting that the office microenvironment is a significant source of PentaBDE exposure among office workers. In Chapter 3 we explore relationships between PBDEs in office dust, handwipes, and serum. We found that handwipes collected in the office microenvironment were correlated with both office dust and serum, providing a link between the office microenvironment and body burden. This suggests that handwipes may provide a measure of personal exposure to PBDEs in the surrounding environment, and exposure likely occurs via hands, either through incidental ingestion or dermal absorption. In Chapter 4 we examine the relative contributions of diet and dust from the home, office, and car microenvironments to PentaBDE body burden. We found that the main living area and bedroom microenvironments of the home were the most predictive of PentaBDE concentrations in serum. Although previous studies found associations between meat and dairy intake and PentaBDE body burden, diet did not predict PentaBDEs in serum in this study population.
Download or read book Exposure of Humans to Polybrominated Diphenyl Ethers PBDEs Via Residential Indoor Environment in the U S written by Hua He and published by . This book was released on 2012 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Assessing Exposure to Polybrominated Diphenyl Ethers PBDEs in the Home Environment written by Joseph Gardner Allen and published by . This book was released on 2008 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Polybrominated diphenyl ethers (PBDEs) are a class of toxic fire retardant compounds commonly used in household furniture and electronics. Human exposure to PBDEs primarily occurs in the indoor environment and levels in household dust have been linked to PBDE levels in breast milk. Further investigation of the home environment was necessary to improve our understanding of how PBDE sources contribute to personal exposure via both air and dust. In our first paper, we reported the first personal air concentrations of PBDEs in a non- occupational setting, and the first air concentrations in the United States. Further, we reported on BDE 209, a congener not widely reported in air. Concentrations of PBDEs were higher in personal air than in area air, particularly for the less volatile compounds, consistent with a personal cloud effect. We found that inhalation exposure may account for up to 22% of BDE 209 exposure in adults, far higher than previously estimated. Our second paper evaluated factors critical to assessing exposure to PBDEs in house dust. Concentrations of PBDEs in dust did not exhibit temporal variability over an 8-month period suggesting that cross-sectional sampling may be representative of exposure. Researcher-collected dust was up to 3.3 times higher, on average, than dust from the home vacuum bag. Concentrations of PBDEs in dust were significantly higher in the main living area compared with the bedroom, indicating spatial heterogeneity within homes. PBDE concentrations in air and dust were correlated, but only for the pentaBDE congeners and not decaBDE. Lastly, two dust exposure metrics (ng/g and ng/m 2) were strongly correlated, suggesting similar dust loadings across homes in our sample. In our final paper, we used X-ray fluorescence (XRF) to quantify bromine in consumer products and then relate those measures to room-specific concentrations of PBDEs in dust. In the validation phase, we demonstrated that XRF is a reliable predictor of bromine in products compared with GC/MS. In the field study phase, we found associations between XRF-measured bromine content in furniture and pentaBDE concentrations in dust from the same room. We also found that XRF-measured bromine levels in televisions were associated with decaBDE concentrations in dust, with the number of residents acting as an effect modifier.
Download or read book Child specific Exposure Factors Handbook written by and published by . This book was released on 2002 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Assessing Exposure to Polybrominated Diphenyl Ethers and Polyfluorinated Compounds from Diet and the Indoor Environment written by Alicia June Fraser and published by . This book was released on 2010 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: This dissertation examines exposure of the general population to two classes of persistent organic pollutants, polybrominated diphenyl ethers (PBDEs) and polyfluorinated compounds (PFCs), both of which are used in consumer products. Exposure is known to occur in the indoor environment and via diet, though the relative contribution of different exposure pathways and microenvironments to human body burdens is poorly understood. Chapter 2 investigates the association between diet and serum concentrations of PBDEs in the general U.S. population The study sample consists of 1,971 participants of the 2003-2004 National Health and Nutrition Examination Survey. Using both a 24-hour food recall and a 1-year food frequency questionnaire, food categories were examined as predictors of five PBDEs (BDE-28, 47, 99, 100, and 153), and their sum (ΣPBDE) while adjusting for age, sex, race/ethnicity, income, and BMI. Consumption of poultry and red meat contributed significantly to PBDE body burdens and vegetarians had 25% lower ΣPBDE serum concentrations than omnivores. Chapters 3 and 4 investigate the role of indoor air and dust exposure to PFC body burdens among 31 individuals living and working in Boston, MA. Week-long, active air samples were collected from participant offices while dust samples were collected from offices, homes, and vehicles. Air samples were measured for the volatile PFC precursor compounds fluorotelomer alcohols (FTOHs), sulfonamides (FOSAs), and sulfonamidoethanols (FOSEs). Dust samples were analyzed for 19 PFCs, including perfluorooctanoate (PFOA), perfluorooctane sulfonate (PFOS), FTOHs, FOSAs, and FOSEs. Serum samples were also collected from participants and analyzed for eight PFCs including PFOA and PFOS. FTOH concentrations in office air, particularly 8:2-FTOH, were much higher than FOSAs and FOSEs, and varied by building with the highest levels observed in a newly constructed and newly furnished building. FTOHs in air were significantly associated with PFOA in serum. PFOS in serum was not associated with air levels of FOSAs/FOSEs. PFC concentrations in dust varied by microenvironment and, in general, were found to be highest in offices and not associated with PFCs in serum. In conclusion, diet is an important exposure pathway for PBDEs, and office air may be an important contributor to PFOA body burden.
Download or read book The Significance of Indoor Air as a Source of Human Exposure to Polybrominated Diphenyl Ethers PBDEs and Polychlorinated Biphenyl PCBs written by Sadegh Hazrati and published by . This book was released on 2006 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Signiflcance of Indoor Air as a Source of Human Exposure to Polybrominated Diphenyl Ethers PBDEs and Polychlorinated Biphenyls PCBs written by Sadegh Hazrati and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Inhalation Exposure Pathways for Polybrominated Diphenyl Ethers written by Scot Waye and published by . This book was released on 2008 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many chemicals off-gas or leech into indoor environments from sources such as consumer products, furnishings, and building materials. An understanding of the pathways from the sources to human exposure is vital in order to implement control strategies and lower exposure. Objects containing Brominated flame retardants (BFRs), one class of semivolatile organic compounds (SVOCs), burn more slowly during combustion. BFRs, especially polybrominated diphenyl ethers (PBDEs), are used in electronic devices including casings and circuit boards. Heat from internal circuitry increases the BFR vapor pressure and the partition coefficient, enhancing its transport out of the substrate and into the indoor environment. In this work, a computer tower in an office setting provides a case study to examine the emissions of, and exposure to, PBDEs. the case of a computer tower, the cooling fan increases the mass transfer coefficient, further increasing emissions. During computer use, the emission rate of PBDEs from the interior of the case is more than double the emission rate from the exterior of the case due to elevated internal temperatures and higher mass transfer due to the cooling fan. The concentration of PBDEs in the room air increases 40 - 80% for every 5°C increase inside the computer case, depending on the PBDE congener. Such enhanced emissions are a concern since recent studies have shown adverse health effects of PBDEs on human health. The major contributions of this work are: A model was developed that is useful for SVOC emissions for various heat and mass transfer situations, including diffusion through the slab and convective boundary conditions on each side of the slab, which may be simplified if the situation warrants; A systematic propagation of the uncertainties and variability of the model parameters was accomplished by using a Monte Carlo method for the input of the parameters into the model; A polydisperse indoor particle distribution was used as a sink, identifying the size-discretized particle phase PBDE concentration; An exposure assessment showed that the inhalation pathway for PBDEs in the gas and particulate phases is relevant and that the particulate phase exposure is dominant.
Download or read book Application of Systematic Review Methods in an Overall Strategy for Evaluating Low Dose Toxicity from Endocrine Active Chemicals written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2017-08-14 with total page 423 pages. Available in PDF, EPUB and Kindle. Book excerpt: To safeguard public health, the US Environmental Protection Agency (EPA) must keep abreast of new scientific information and emerging technologies so that it can apply them to regulatory decision-making. For decades the agency has dealt with questions about what animal-testing data to use to make predictions about human health hazards, how to perform dose-response extrapolations, how to identify and protect susceptible subpopulations, and how to address uncertainties. As alternatives to traditional toxicity testing have emerged, the agency has been faced with additional questions about how to incorporate data from such tests into its chemical assessments and whether such tests can replace some traditional testing methods. Endocrine active chemicals (EACs) have raised concerns that traditional toxicity-testing protocols might be inadequate to identify all potential hazards to human health because they have the ability to modulate normal hormone function, and small alterations in hormone concentrations, particularly during sensitive life stages, can have lasting and significant effects. To address concerns about potential human health effects from EACs at low doses, this report develops a strategy to evaluate the evidence for such low-dose effects.
Download or read book Indoor Environment written by Lidia Morawska and published by John Wiley & Sons. This book was released on 2006-12-13 with total page 467 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covering the fundamentals of air-borne particles and settled dust in the indoor environment, this handy reference investigates: * relevant definitions and terminology, * characteristics, * sources, * sampling techniques and instrumentation, * exposure assessment, * monitoring methods. The result is a useful and comprehensive overview for chemists, physicists and biologists, postgraduate students, medical practitioners, occupational health professionals, building owners and managers, building, construction and air-conditioning engineers, architects, environmental lawyers, government and regulatory professionals.
Download or read book Emerging Pollutants in the Environment written by Marcelo Larramendy and published by BoD – Books on Demand. This book was released on 2015-09-02 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: This edited book, Emerging Pollutants in the Environment Current and Further Implications, includes overviews by significant researchers on the topic of emerging pollutants toxicology, which covers the hazardous effects of common emerging xenobiotics employed in our every day anthropogenic activities. We hope that this book will meet the expectations and needs of all those who are interested in the negative implications of several emerging pollutants on living species.
Download or read book Assessing Polybrominated Diphenyl Ethers PBDEs in Indoor Environments written by Jinyu Yang and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Emerging Contaminants written by Aurel Nuro and published by BoD – Books on Demand. This book was released on 2021-05-27 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: Emerging Contaminants presents the reader with information on classification, recent studies, and adverse effects on the environment and human health of the main classes of contaminants. Emerging contaminants are synthetic or natural compounds and microorganisms produced and used by humans that cause adverse ecological and human health effects when they reach the environment. This book is organized into four sections that cover the classification of contaminants and the instrumental techniques used to quantify them, recent studies on pesticides, antibiotics as an important group of emerging contaminants, and studies of different classes of emerging contaminants such as polybrominated diphenyl ethers (PBDEs), microplastics, and others.
Download or read book Measurement and Modeling of Polybrominated Diphenyl Ethers PBDEs and Polychlorinated Biphenyls PCBs in the Indoor Environment written by Xianming Zhang and published by . This book was released on 2008 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt: The indoor environment is a potentially dominant source of exposure for polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs). This thesis describes a study on levels, sources, emissions, and fate of PBDEs and PCBs indoors. PBDEs and PCBs air levels in 20 indoor environments in Toronto were sampled and measured. The geometric means of PBDE (Sigma10BDE) and PCB (Sigma35PCB) concentrations were 0.072 and 7.2 ng·m-3 respectively. Statistical analysis on chemical profiles distinguished the chemical sources in the 20 environments. A multimedia indoor environmental model was applied on two test rooms. Estimated PBDE and PCB emission rates were 5.4--550 ng·h -1 and 280--5870 ng·h-1 respectively. Particle movement dominates within-room transport processes, and dust removal and air advection are the main chemical loss processes. Temperature, particle concentration and deposition velocity, and air exchange rate are the most influential parameters, which can alter source or sink behaviors of household products for the chemicals.
Download or read book Polybrominated Diphenyl Ethers PBDEs in Indoor and Outdoor Environments written by Dudsadee Muenhor and published by . This book was released on 2011 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Human Biomonitoring for Environmental Chemicals written by National Research Council and published by National Academies Press. This book was released on 2006-11-30 with total page 317 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biomonitoring—a method for measuring amounts of toxic chemicals in human tissues—is a valuable tool for studying potentially harmful environmental chemicals. Biomonitoring data have been used to confirm exposures to chemicals and validate public health policies. For example, population biomonitoring data showing high blood lead concentrations resulted in the U.S. Environmental Protection Agency's (EPA's) regulatory reduction of lead in gasoline; biomonitoring data confirmed a resultant drop in blood lead concentrations. Despite recent advances, the science needed to understand the implications of the biomonitoring data for human health is still in its nascent stages. Use of the data also raises communication and ethical challenges. In response to a congressional request, EPA asked the National Research Council to address those challenges in an independent study. Human Biomonitoring for Environmental Chemicals provides a framework for improving the use of biomonitoring data including developing and using biomarkers (measures of exposure), research to improve the interpretation of data, ways to communicate findings to the public, and a review of ethical issues.
Download or read book Polybrominated Diphenyl Ethers PBDEs as Emerging Environmental Pollutants written by Elizabeth Ndunda and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Environmental pollution has been a challenging phenomenon in most developing countries, due to the weak enforcement of environmental regulations. As a result, humans and animals are exposed to different environmental pollutants, which threaten their very existence. Some of the emerging pollutants of great concern are polybrominated diphenyl ethers (PBDEs) since they are categorized as probable human carcinogens and are also known to bioaccumulate in fatty tissues of animals and humans, reaching toxic levels upon continued exposure. Monitoring of these pollutants is therefore paramount as it contributes to addressing the problem of human exposure and environmental pollution. Their monitoring involves sample preparation methods followed by quantification with various detection techniques. Sample preparation methods that aim at reducing matrix interferences, enriching analytes and transfer of analytes to a desirable solvent, have evolved from conventional methods to advanced methods that facilitate the detection of these chemicals at very low concentrations. Likewise, detection techniques have advanced from chromatographic detection techniques to miniaturized systems that involve sensors. This chapter discusses PBDEs as emerging pollutants, their sources, and toxicological implications on humans, as well as advances in sample preparation methods and detection techniques in the determination of PBDEs.
