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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Building hypotheses to understand the synergistic effects of heat and pollution exposure in a changing climate

The increasing intensity, frequency, and duration of extreme weather events due to climate change poses a broad range of health risks, and the synergistic effects of extreme temperature co-occurring with other hazardous exposures such as air pollution may result in higher risks of all-cause mortality and cardiovascular and respiratory morbidity than exposure to either event alone. There are a number of hypothesized mechanisms for this interaction effect, including increased susceptibility to heat effects on chronic conditions affected by air pollution exposure, exacerbation of pollution effects due to temperature-induced stress, and shared pathophysiological pathways (e.g., systemic inflammation), but specific physiological mechanisms are not well understood. In this editorial, the authors discuss this aspect of a recently published study examining ambient formaldehyde combined with high temperature exposure and respiratory disease admissions among children. Here, the observation that the health effects of pollutants such as formaldehyde are amplified following periods of high temperature can help inform risk warning systems even without knowledge of the underlying physiological mechanisms, but a deeper biological understanding of the interaction effects of heat and ambient air pollution may better inform interventions. This is even more important in view of increases in both extreme temperature and pollution events tied to climate change.

Chambliss, Sarah [University of Texas at Austin, T↗
DOE OSTI2014

Pollutant Exposures from Natural Gas Cooking Burners: A Simulation-Based Assessment for Southern California

Background: Residential natural gas cooking burners (NGCBs) can emit substantial quantities of pollutants, and they are typically used without venting range hoods. Objective: We quantified pollutant concentrations and occupant exposures resulting from NGCB use in California homes. Methods: A mass-balance model was applied to estimate time-dependent pollutant concentrations throughout homes in Southern California and the exposure concentrations experienced by individual occupants. We estimated nitrogen dioxide (NO2), carbon monoxide (CO), and formaldehyde (HCHO) concentrations for 1 week each in summer and winter for a representative sample of Southern California homes. The model simulated pollutant emissions from NGCBs as well as NO2 and CO entry from outdoors, dilution throughout the home, and removal by ventilation and deposition. Residence characteristics and outdoor concentrations of NO2 and CO were obtained from available databases. We inferred ventilation rates, occupancy patterns, and burner use from household characteristics. We also explored proximity to the burner(s) and the benefits of using venting range hoods. Replicate model executions using independently generated sets of stochastic variable values yielded estimated pollutant concentration distributions with geometric means varying by < 10%. Results: The simulation model estimated that—in homes using NGCBs without coincident use of venting range hoods—62%, 9%, and 53% of occupants are routinely exposed to NO2, CO, and HCHO levels that exceed acute health-based standards and guidelines. NGCB use increased the sample median of the highest simulated 1-hr indoor concentrations by 100, 3,000, and 20 ppb for NO2, CO, and HCHO, respectively. Conclusions: Reducing pollutant exposures from NGCBs should be a public health priority. Simulation results suggest that regular use of even moderately effective venting range hoods would dramatically reduce the percentage of homes in which concentrations exceed health-based standards.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2014

Pollutant Exposures from Natural Gas Cooking Burners: A Simulation-Based Assessment for Southern California

Residential natural gas cooking burners (NGCBs) can emit substantial quantities of pollutants and they are typically used without venting. The objective of this study is to quantify pollutant concentrations and occupant exposures resulting from NGCB use in California homes. A mass balance model was applied to estimate time-dependent pollutant concentrations throughout homes and the "exposure concentrations" experienced by individual occupants. The model was applied to estimate nitrogen dioxide (NO{sub 2}), carbon monoxide (CO), and formaldehyde (HCHO) concentrations for one week each in summer and winter for a representative sample of Southern California homes. The model simulated pollutant emissions from NGCBs, NO{sub 2} and CO entry from outdoors, dilution throughout the home, and removal by ventilation and deposition. Residence characteristics and outdoor concentrations of CO and NO{sub 2} were obtained from available databases. Ventilation rates, occupancy patterns, and burner use were inferred from household characteristics. Proximity to the burner(s) and the benefits of using venting range hoods were also explored. Replicate model executions using independently generated sets of stochastic variable values yielded estimated pollutant concentration distributions with geometric means varying less than 10%. The simulation model estimates that in homes using NGCBs without coincident use of venting range hoods, 62%, 9%, and 53% of occupants are routinely exposed to NO{sub 2}, CO, and HCHO levels that exceed acute health-based standards and guidelines. NGCB use increased the sample median of the highest simulated 1-hr indoor concentrations by 100, 3000, and 20 ppb for NO{sub 2}, CO, and HCHO, respectively. Reducing pollutant exposures from NGCBs should be a public health priority. Simulation results suggest that regular use of even moderately effective venting range hoods would dramatically reduce the percentage of homes in which concentrations exceed health-based standards.

03 NATURAL GAS↗
DOE OSTI2023

Riverine Plastic Pollution: Field Sampling Protocol and Implementation in U.S. Rivers

Riverine plastic pollution is increasingly being recognized as a serious environmental concern. The flux of plastic from U.S. rivers into the oceans is estimated to be on the order of hundreds of tons per year. Plastic pollution has been detected in all major U.S. rivers but the observations did not measure metrics that could be used for mass flux calculations. The Department of Energy is addressing the problem of riverine plastic pollution with the Waterborne Plastics Resource Assessment and Debris Characterization (WaterPACT) project. Phase one of the WaterPACT project includes the development of a sampling protocol, field sampling events that implement the protocol, and numerical modeling studies. The field sampling will quantify and characterize the plastic pollution and the numerical modeling studies will analyze the movement of the plastic pollution by rivers. This report details the WaterPACT sampling protocol and its implementation in four major U.S. rivers. The WaterPACT sampling protocol was implemented in the Mississippi, Columbia, Delaware, and Los Angeles rivers with at least three sampling events in each river. The rivers represent four types ranging from the large Mississippi with its vast agricultural watershed to the small Los Angeles with its highly engineered urban waterway. The three sampling events covered a variety of discharge conditions from low drought flow to extreme storm events. The data obtained by the WaterPACT sampling of the four rivers will be combined to provide an invaluable dataset to researchers studying the source and chemical composition of plastic pollution and modelers estimating the flux of plastic being transported to and released into the oceans.

13 HYDRO ENERGY↗
NASA NTRS2007

NASA's Potential Contributions for Using Solar Ultraviolet Radiation in Conjunction with Photocatalysis for Urban Air Pollution Mitigation

More than 75 percent of the U.S. population lives in urban communities where people are exposed to levels of smog or pollution that exceed the EPA (U.S. Environmental Protection Agency) safety standards. Urban air quality presents a unique problem because of a number of complex variables, including traffic congestion, energy production, and energy consumption activities, all of which can contribute to and affect air pollution and air quality in this environment. In environmental engineering, photocatalysis is an area of research whose potential for environmental clean-up is rapidly developing popularity and success. Photocatalysis, a natural chemical process, is the acceleration of a photoreaction in the presence of a catalyst. Photocatalytic agents are activated when exposed to near UV (ultraviolet) light (320-400 nm) and water. In recent years, surfaces coated with photocatalytic materials have been extensively studied because pollutants on these surfaces will degrade when the surfaces are exposed to near UV light. Building materials, such as tiles, cement, glass, and aluminum sidings, can be coated with a thin film of a photocatalyst. These coated materials can then break down organic molecules, like air pollutants and smog precursors, into environmentally friendly compounds. These surfaces also exhibit a high affinity for water when exposed to UV light. Therefore, not only are the pollutants decomposed, but this superhydrophilic nature makes the surface self-cleaning, which helps to further increase the degradation rate by allowing rain and/or water to wash byproducts away. According to the Clean Air Act, each individual state is responsible for implementing prevention and regulatory programs to control air pollution. To operate an air quality program, states must adopt and/or develop a plan and obtain approval from the EPA. Federal approval provides a means for the EPA to maintain consistency among different state programs and ensures that they comply with the requirements of the Clean Air Act.

Ryan, robert E.↗
NASA NTRS2007

Solutions Network Formulation Report. NASA's Potential Contributions for Using Solar Ultraviolet Radiation in Conjunction with Photocatalysis for Urban Air Pollution Mitigation and Increasing Air Quality

This Candidate Solution is based on using NASA Earth science research on atmospheric ozone and aerosols data as a means to predict and evaluate the effectiveness of photocatalytically created surfaces (building materials like glass, tile and cement) for air pollution mitigation purposes. When these surfaces are exposed to near UV light, organic molecules, like air pollutants and smog precursors, will degrade into environmentally friendly compounds. U.S. EPA (Environmental Protection Agency) is responsible for forecasting daily air quality by using the Air Quality Index (AQI) that is provided by AIRNow. EPA is partnered with AIRNow and is responsible for calculating the AQI for five major air pollutants that are regulated by the Clean Air Act. In this Solution, UV irradiance data acquired from the satellite mission Aura and the OMI Surface UV algorithm will be used to help understand both the efficacy and efficiency of the photocatalytic decomposition process these surfaces facilitate, and their ability to reduce air pollutants. Prediction models that estimate photocatalytic function do not exist. NASA UV irradiance data will enable this capability, so that air quality agencies that are run by state and local officials can develop and implement programs that utilize photocatalysis for urban air pollution control and, enable them to make effective decisions about air pollution protection programs.

Underwood, Lauren↗
NASA NTRS2019

Chemical Climatology of Atmospheric Pollutants in the Eastern United States: Seasonal/Diurnal Cycles and Contrast Under Clear/Cloudy Conditions for Remote Sensing

We statistically assessed temporal variations of observed concentrations of eight atmospheric pollutants (SO2, NO, NO2, NO(y), O3, CO, NH3, and HNO3) at three urban sites and one rural site in the eastern United States for a ten-year period (4 years for NH3). Diurnal/seasonal patterns of observed mean concentrations and their decade-scale trends under different weather conditions were evaluated. Concentrations of pollutants decreased consistently during the observation period (as long as 1997–2013), although nighttime ozone during winter appears to increase because of reduced NO-O3 titration. This study shows that the decay time of major air pollutant concentrations such as SO2 and NO(x) can be short as a few hours to one day. We also identified substantial differences between the mean concentrations of pollutants at clear sky and overcast conditions that could introduce biases into satellite observations. Surface concentrations of SO2 and CO are distinctly higher under cloud free than under overcast conditions by ∼30% and ∼20% respectively. NO2 shows a complex pattern, but demonstrates lower daytime concentrations under cloud-free skies. All of these estimates are important for understanding the chemical climatology of these atmospheric pollutants, especially their diurnal/seasonal cycles under different weather conditions. For four-year measurements, NH3 shows a substantial difference, with clear sky observations roughly a factor of two higher than those under overcast conditions. To track changes in the future, the full daily cycle of atmospheric pollutants monitored by geostationary satellite such as the future TEMPO mission may better capture patterns and trends.

TEMPO↗
DOE OSTI2018

Traffic-related air pollution and childhood obesity in an Italian birth cohort

Highlights: • Few studies analyse the association between air pollution and children BMI. • We modelled traffic-related air pollution with land-use regression models. • Inverse Probability Weighting (IPW) has been used to control for selection bias. • No association was found between pollutants and ponderal excess parameters. Air pollution is associated with several adverse health outcomes in children, such as respiratory illnesses and cognitive development impairment. There are suggestions of an effect of traffic-related air pollution on the occurrence of childhood obesity, but the results are not consistent.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Temporal trends in air pollution exposure inequality in Massachusetts

Highlights: • We characterized longitudinal PM{sub 2.5} and NO{sub 2} inequality trends across Massachusetts. • Exposure inequality increased in urban, but not rural areas. • NO{sub 2} exposure inequality was greater in magnitude than PM{sub 2.5} inequality. • Observed inequality trends likely driven by spatiotemporal pollution shifts. Mounting evidence over the past several decades has demonstrated inequitable distribution of pollutants of ambient origin between sociodemographic groups in the United States. Most environmental inequality studies to date are cross-sectional and used proximity-based methods rather than modeled air pollution concentrations, limiting the ability to examine trends over time or the factors that drive exposure inequalities. In this paper, we use 1 km{sup 2} modeled PM{sub 2.5} and NO{sub 2} concentrations in Massachusetts over an 8-year period and Census demographic data to quantify inequality between sociodemographic groups and to develop a more nuanced understanding of the drivers and trends in longitudinal air pollution inequality. Annual-average population-weighted PM{sub 2.5} and NO{sub 2} concentrations were highest for urban non-Hispanic black populations (11.8 µg/m{sup 3} in 2003 and 8.4 µg/m{sup 3} in 2010, vs. 11.3 µg/m{sup 3} and 8.1 µg/m{sup 3} for urban non-Hispanic whites) and urban Hispanic populations (15.9 ppb in 2005 and 13.0 ppb in 2010, vs. 13.0 ppb and 10.2 ppb for urban non-Hispanic whites), respectively. While population groups experienced similar absolute decreases in exposure over time, disparities in population-weighted concentrations increased over time when quantified by the Atkinson Index, a relative inequality measure. Exposure inequalities were approximately one order of magnitude greater for NO{sub 2} compared to PM{sub 2.5}, were more pronounced in urban compared to rural geographies, and between racial/ethnic groups compared to income and educational attainment groups. Our results also revealed similar longitudinal PM{sub 2.5} and NO{sub 2} inequality trends using Census 2000 and Census 2010 data, indicating that spatio-temporal shifts in air pollution may best explain observed trends in inequality. These findings enhance our understanding of factors that contribute to persistent inequalities and underscore the importance of targeted exposure reduction strategies aimed at vulnerable populations and neighborhoods.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Toxic metal(loid)-based pollutants and their possible role in autism spectrum disorder

Highlights: • There is a significant relationship between ASD and various environmental factors. • A possible association exists between ASD and exposure to toxic metals. • Lead, mercury, aluminum, and arsenic may be involved in the etiology of ASD. • Toxic metals may induce neuroinflammation and oxidative stress. • Modulation of toxic metal body burden may improve ASD. Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by deficits in social interaction, verbal and non-verbal communication, and stereotypic behaviors. Many studies support a significant relationship between many different environmental factors in ASD etiology. These factors include increased daily exposure to various toxic metal-based environmental pollutants, which represent a cause for concern in public health. This article reviews the most relevant toxic metals, commonly found, environmental pollutants, i.e., lead (Pb), mercury (Hg), aluminum (Al), and the metalloid arsenic (As). Additionally, it discusses how pollutants can be a possible pathogenetic cause of ASD through various mechanisms including neuroinflammation in different regions of the brain, fundamentally occurring through elevation of the proinflammatory profile of cytokines and aberrant expression of nuclear factor kappa B (NF-κB). Due to the worldwide increase in toxic environmental pollution, studies on the role of pollutants in neurodevelopmental disorders, including direct effects on the developing brain and the subjects’ genetic susceptibility and polymorphism, are of utmost importance to achieve the best therapeutic approach and preventive strategies.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2011

Economically consistent long-term scenarios for air pollutant emissions

Pollutant emissions such as aerosols and tropospheric ozone precursors substantially influence climate. While future century-scale scenarios for these emissions have become more realistic through the inclusion of emission controls, they still potentially lack consistency between surface pollutant concentrations and regional levels of affluence. We demonstrate a methodology combining use of an integrated assessment model and a three-dimensional atmospheric chemical transport model, whereby a reference scenario is constructed by requiring consistent surface pollutant levels as a function of regional income over the 21st century. By adjusting air pollutant emission control parameters, we improve agreement between modeled PM2.5 and economic income among world regions through time; agreement for ozone is also improved but is more difficult to achieve because of the strong influence of upwind world regions. The scenario examined here was used as the basis for one of the Representative Concentration Pathway (RCP) scenarios. This analysis methodology could also be used to examine the consistency of other pollutant emission scenarios.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2014

Mobilisation of lipophilic pollutants from blubber in northern elephant seal pups (Mirounga angustirostris) during the post-weaning fast

Northern elephant seals (NES) (Mirounga angustirostris) from the Año Nuevo State Reserve (CA, USA) were longitudinally sampled during the post-weaning fast in order to study the mobilisation and redistribution of various classes of persistent organic pollutants (POPs), such as polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (p,p′-DDE) and hexachlorobenzene (HCB) between blubber and blood. Inner and outer blubber layers were analysed separately. Organohalogenated compounds were detected in all blubber samples in the decreasing order of their concentrations: p,p′-DDE>PCBs⪢HCB>PBDEs. The concentrations of all studied compounds were homogeneously distributed in the blubber layer at early fast, since the concentrations of POPs were statistically not different in the inner and outer layers. With the progression of the fast, the concentrations of PBDEs, PCBs and p,p′-DDE increased more sharply in inner blubber than in outer blubber. As a result, their levels became significantly higher in inner blubber as compared to outer blubber at late fast. The rise of pollutant concentrations in blubber might result from a less efficient mobilisation than triglycerides and/or a reuptake by adipocytes of some of the pollutants released into the circulation. The mobilisation of pollutants from blubber was higher at late fast. An increase of pollutant concentrations was observed in serum between early and late fast. Lower halogenated congeners (i.e. tetra-CBs) were present in higher proportions in serum, whereas the higher halogenated congeners (i.e. hepta-CBs) were mainly found in the inner and outer blubber layers. The transfer ratios of both PBDEs and PCBs from inner blubber to serum decreased with the number of chlorine and bromine atoms. In addition, the distribution of both types of compounds between serum and blubber was strongly influenced by their lipophilic character (log K{sub ow} values), with more lipophilic compounds being less efficiently released from blubber to serum. - Highlights: • The POP concentrations were evenly distributed in blubber layers at early fast. • The POP concentrations were higher in inner than in outer blubber at late fast. • The POP concentrations increased in blubber and serum over the fast. • POPs were less efficiently mobilised from blubber than triglycerides. • The mobilisation of POPs from blubber was influenced by their lipophilic character.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2016

Assessing the pollution risk of a groundwater source field at western Laizhou Bay under seawater intrusion

Coastal areas have great significance for human living, economy and society development in the world. With the rapid increase of pressures from human activities and climate change, the safety of groundwater resource is under the threat of seawater intrusion in coastal areas. The area of Laizhou Bay is one of the most serious seawater intruded areas in China, since seawater intrusion phenomenon was firstly recognized in the middle of 1970s. This study assessed the pollution risk of a groundwater source filed of western Laizhou Bay area by inferring the probability distribution of groundwater Cl{sup −} concentration. The numerical model of seawater intrusion process is built by using SEAWAT4. The parameter uncertainty of this model is evaluated by Markov Chain Monte Carlo (MCMC) simulation, and DREAM{sub (ZS)} is used as sampling algorithm. Then, the predictive distribution of Cl{sup -} concentration at groundwater source field is inferred by using the samples of model parameters obtained from MCMC. After that, the pollution risk of groundwater source filed is assessed by the predictive quantiles of Cl{sup -} concentration. The results of model calibration and verification demonstrate that the DREAM{sub (ZS)} based MCMC is efficient and reliable to estimate model parameters under current observation. Under the condition of 95% confidence level, the groundwater source point will not be polluted by seawater intrusion in future five years (2015–2019). In addition, the 2.5% and 97.5% predictive quantiles show that the Cl{sup −} concentration of groundwater source field always vary between 175 mg/l and 200 mg/l. - Highlights: • The parameter uncertainty of seawater intrusion model is evaluated by MCMC. • Groundwater source field won’t be polluted by seawater intrusion in future 5 years. • The pollution risk is assessed by the predictive quantiles of Cl{sup −} concentration.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Survey on the micro-pollutants presence in surface water system of northern Serbia and environmental and health risk assessment

Highlights: • First survey on the occurrence of 940 substances in the middle part of the Danube Basin. • Micro-pollutants from canals water had higher abundance of contaminants that from river. • High level of sterols indicated dominant effect of untreated domestic wastewater. • Correlations among the groups of micro-pollutants indicated their common origin. • Ecological risk suggesting a potential for adverse effects on fish. This study demonstrates the occurrence of 940 organic micro-pollutants in surface water of four rivers, one irrigation canal system, and two lakes in Vojvodina Province, the northern part of Serbia, summing in total eighteen samples. The number of detected chemicals ranged from 22 to 84, with 127 micro-pollutants detected at least once, representing 13% of the studied substances. The targeted compounds include n-alkanes, sterols, polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides polychlorinated biphenyls, pesticides, pharmaceutical active compounds, industrial chemicals, plasticizers, etc. Among the analysed compounds, sterols were the most dominant with maximum quantified concentrations. The substances which were quantified with frequency over 50% were two PAHs (2-methylnaphthalene, benzo(ghi)perylene), five sterols (cholesterol, cholestanol, stigmasterol, fucosterol, beta-sitosterol), three pharmaceuticals and personal care products (L-menthol, diethyltoluamide, caffeine), and ten household chemicals (4-tert-octylphenol, dimethyl phthalate, methyl palmitate, phenylethyl alcohol, 1-nonanol, alpha-terpineol, 2-phenoxy-ethanol, methyl myristate, acetophenone, and 2-ethyl-1-hexanol). The list of priority substances under the European Union Directive 2013/39/EU includes 49 priority substances (PSs) out of which 34 were analysed. Among these, eleven PSs were quantified, and only two compounds (fluoranthene and benzo (a) pyrene) exceeded EU Environmental Quality Standards targeted values. The obtained results were compared with the previously published data that dealt with the same targeted number of micro-pollutants in sediment samples. This revealed connections between the same sampling locations. Environmental risk assessment showed the existence of potential ecological risk as 72% of the obtained values for the ecological hazard index (HI) at investigated locations were higher that the targeted value (HI > 1). Estimated values for hazard quotient (HQ) and hazard index (HI) for non-carcinogenic risk were lower than the targeted value, indicating no non-carcinogenic risk through dermal contact and non-intentional ingestion of water. Estimated values for cancer risk were all below 1 × 10{sup −6}, which is not considered to pose significant human health risk.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2017

Comparison of the greenhouse gas and criteria pollutant emissions from the SF-BREEZE high-speed fuel-cell ferry with a diesel ferry

A theoretical comparison is made of the “well to waves” (WTW) greenhouse gas (GHG) and criteria pollutant emissions from the SF-BREEZE high-speed hydrogen PEM fuel cell ferry and the VALLEJO ferry powered by traditional diesel engine technology but constrained to Tier 4 emissions standards. The emissions were calculated for a common maritime mission, the current ferry route between Vallejo CA and San Francisco CA. Calculations are made of the energy required for the SF-BREEZE and VALLEJO to perform the mission route profile. The SF-BREEZE requires 10.1% more fuel energy than the VALLEJO, primarily due to the SF-BREEZE being heavier. Estimates are made for the SF-BREEZE GHG emissions associated with five LH2 fuel production pathways including renewable and non-renewable (fossil-fuel based) methods. Estimates are also made for GHG emissions associated with fossil-diesel production and delivery as well as those for biodiesel, which can be considered a renewable “drop-in” fuel replacement for conventional diesel fuel. We find that the GHG emissions for the SF-BREEZE using non-renewable LH 2 are significantly higher than for the Tier 4 diesel-fueled VALLEJO on a per passenger basis. However, using renewable LH 2 , the GHG emissions for the SF-BREEZE ferry are reduced 75.8% compared to the diesel-fueled VALLEJO operating at Tier 4 emissions standards. We also compare the criteria pollutant emissions (NO x , HC, PM 10 ) for the SF-BREEZE to that of the VALLEJO held to Tier 4 emissions standards fueled by diesel fuel or biodiesel. Hydrogen PEM fuel cell technology dramatically reduces NO x and HC emissions below the most advanced Tier 4 criteria pollutant emissions requirements regardless of whether the LH 2 is made by NG reforming or via water electrolysis using 70% renewable energy. Renewable LH 2 made with greater than 84% renewable process energy is needed to also drop the SF-BREEZE PM 10 emissions below that of Tier 4 for high-speed fuel cell ferry transportation. Overall, the results show that operating a hydrogen fuel cell ferry on nearly 100% renewable hydrogen provides the dramatic reduction in GHG and criteria pollutant emissions commensurate with the problems of global climate change and maritime air pollution worldwide.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2022

Metal-organic frameworks as effective sensors and scavengers for toxic environmental pollutants

Abstract Metal-organic frameworks (MOFs) constructed from a rich library of organic struts and metal ions/clusters represent promising candidates for a wide range of applications. The unique structure, porous nature, easy tunability and processability of these materials make them an outstanding class of materials for tackling serious global problems relating to energy and environment. Among them, environmental pollution is one aspect that has increased at an alarming rate in the past decade or so. With rapid urbanization and industrialization, toxic environmental pollutants are constantly released and accumulated leading to serious contamination in water bodies and thereby having adverse effects on human health. Recent studies have shown that many toxic pollutants, as listed by the World Health Organization and the US Environmental Protection Agency, can be selectively detected, captured, sequestered and removed by MOFs from air and aquatic systems. Most of these sensing/capture processes in MOFs are quantifiable and effective for even a trace amount of the targeted chemical species. The functional sites (ligands and metals) play a critical role in such recognition processes and offer an extensive scope of structural tunability for guest (pollutants, toxic entities) recognition. Whereas on the one hand, the underlying mechanisms governing such sensing and capture are important, it is also crucial to identify MOFs that are best suited for commercial applications for the future. In this review article, we provide an overview of the most recent progress in the sensing, capture and removal of various common toxic pollutants, including neutral and ionic, inorganic and organic species, with brief discussions on the mechanism and efficacy of selected MOFs.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2012

Impact of Natural Gas Appliances on Pollutant Levels in California Homes

This report presents results from the first year of a 2-year study, investigating associations of five air pollutants (CO, NO 2 , NO X , formaldehyde and acetaldehyde) with the presence of natural gas appliances in California homes. From November 2011 to March 2012, pollutant concentration and occupant activity data were collected in 155 homes for 6-day periods. The sample population included both single-family (68%) and multi-family (32%) dwellings, with 87% having at least one gas appliance and 77% having an unvented gas cooking appliance. The geometric mean (GM) NO 2 levels measured in the kitchen, bedroom and outside of homes were similar at values of 15, 12 and 11 ppb, respectively. In contrast, the GM NO X levels measured in the kitchen and bedroom of homes were much higher than levels measured outdoors, at levels of 42 and 41 ppb, compared to 19 ppb, respectively. Roughly 10% of sampled homes had 6-day average NO2 levels that exceeded the outdoor annual average limit set by the California Ambient Air Quality Standards (CAAQS) (30 ppb). The GMs of the highest 1-h and 8-h CO level measured in homes were 2.5 and 1.1 ppm, respectively. Four homes had a 1-h or 8-h concentration that exceeded the outdoor limits set by the CAAQS. The GM formaldehyde and acetaldehyde concentrations measured in homes were 15 and 7 ppb, respectively. Roughly 95% of homes had average formaldehyde levels indoors that exceeded the Chronic Reference Exposure Level set by the California EPA (7 ppb). Concentrations of NO 2 and NO X , and to a lesser extent CO were associated with use of gas appliances, particularly unvented gas cooking appliances. Based on first principles, it is expected that effective venting of cooking pollutant emissions at the source will lead to a reduction of pollutant concentrations. However, no statistical association was detected between kitchen exhaust fan use and pollutant concentrations in homes in this study where gas cooking occurred frequently. The lack of statistical

03 NATURAL GAS↗
DOE OSTI2017

A Multivariate Dynamic Spatial Factor Model for Speciated Pollutants and Adverse Birth Outcomes

Evidence suggests that exposure to elevated concentrations of air pollution during pregnancy is associated with increased risks of birth defects and other adverse birth outcomes. While current regulations put limits on total PM2.5 concentrations, there are many speciated pollutants within this size class that likely have distinct effects on perinatal health. However, due to correlations between these speciated pollutants, it can be difficult to decipher their effects in a model for birth outcomes. To combat this difficulty, we develop a multivariate spatio-temporal Bayesian model for speciated particulate matter using dynamic spatial factors. These spatial factors can then be interpolated to the pregnant women’s homes to be used to model birth defects. The birth defect model allows the impact of pollutants to vary across different weeks of the pregnancy in order to identify susceptible periods. Here, the proposed methodology is illustrated using pollutant monitoring data from the Environmental Protection Agency and birth records from the National Birth Defect Prevention Study.

54 ENVIRONMENTAL SCIENCES↗