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1.
Nat Commun ; 15(1): 5880, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-38997317

RESUMO

China's strategy to concurrently address climate change and air pollution mitigation is hindered by a lack of comprehensive information on source contributions to health damage and carbon emissions. Here we show notable discrepancies between source contributions to CO2 emissions and fine particulate matter (PM2.5)-related mortality by using adjoint emission sensitivity modeling to attribute premature mortality in 2017 to 53 sector and fuel/process combinations with high spatial resolution. Our findings reveal that monetized PM2.5 health damage exceeds climate impacts in over half of the analyzed subsectors. In addition to coal-fired energy generators and industrial boilers, the combined health and climate costs from energy-intensive processes, diesel-powered vehicles, domestic coal combustion, and agricultural activities exceed 100 billion US dollars, with health-related costs predominating. This research highlights the critical need to integrate the social costs of health damage with climate impacts to develop more balanced mitigation strategies toward these dual goals, particularly during fuel transition and industrial structure upgrading.

2.
Environ Sci Technol ; 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38943591

RESUMO

Smoke from wildfires poses a substantial threat to health in communities near and far. To mitigate the extent and potential damage of wildfires, prescribed burning techniques are commonly employed as land management tools; however, they introduce their own smoke-related risks. This study investigates the impact of prescribed fires on daily average PM2.5 and maximum daily 8-h averaged O3 (MDA8-O3) concentrations and estimates premature deaths associated with short-term exposure to prescribed fire PM2.5 and MDA8-O3 in Georgia and surrounding areas of the Southeastern US from 2015 to 2020. Our findings indicate that over the study domain, prescribed fire contributes to average daily PM2.5 by 0.94 ± 1.45 µg/m3 (mean ± standard deviation), accounting for 14.0% of year-round ambient PM2.5. Higher average daily contributions were predicted during the extensive burning season (January-April): 1.43 ± 1.97 µg/m3 (20.0% of ambient PM2.5). Additionally, prescribed burning is also responsible for an annual average increase of 0.36 ± 0.61 ppb in MDA8-O3 (approximately 0.8% of ambient MDA8-O3) and 1.3% (0.62 ± 0.88 ppb) during the extensive burning season. We estimate that short-term exposure to prescribed fire PM2.5 and MDA8-O3 could have caused 2665 (95% confidence interval (CI): 2249-3080) and 233 (95% CI: 148-317) excess deaths, respectively. These results suggest that smoke from prescribed burns increases the mortality. However, refraining from such burns may escalate the risk of wildfires; therefore, the trade-offs between the health impacts of wildfires and prescribed fires, including morbidity, need to be taken into consideration in future studies.

3.
Sci Total Environ ; 946: 174197, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38914336

RESUMO

The 2022 wildfires in New Mexico, United States, were unparalleled compared to past wildfires in the state in both their scale and intensity, resulting in poor air quality and a catastrophic loss of habitat and livelihood. Among all wildfires in New Mexico in 2022, six wildfires were selected for our study based on the size of the burn area and their proximity to populated areas. These fires accounted for approximately 90 % of the total burn area in New Mexico in 2022. We used a regional chemical transport model and data-fusion technique to quantify the contribution of these six wildfires (April 6 to August 22) on particulate matter (PM2.5: diameter ≤ 2.5 µm) and ozone (O3) concentrations, as well as the associated health impacts from short-term exposure. We estimated that these six wildfires emitted 152 thousand tons of PM2.5 and 287 thousand tons of volatile organic compounds to the atmosphere. We estimated that the average daily wildfire smoke PM2.5 across New Mexico was 0.3 µg/m3, though 1 h maximum exceeded 120 µg/m3 near Santa Fe. Average wildfire smoke maximum daily average 8-h O3 (MDA8-O3) contribution was 0.2 ppb during the study period over New Mexico. However, over the state 1 h maximum smoke O3 exceeded 60 ppb in some locations near Santa Fe. Estimated all-cause excess mortality attributable to short term exposure to wildfire PM2.5 and MDA8-O3 from these six wildfires were 18 (95 % Confidence Interval (CI), 15-21) and 4 (95 % CI: 3-6) deaths. Additionally, we estimate that wildfire PM2.5 was responsible for 171 (95 %: 124-217) excess cases of asthma emergency department visits. Our findings underscore the impact of wildfires on air quality and human health risks, which are anticipated to intensify with global warming, even as local anthropogenic emissions decline.

4.
Environ Pollut ; 354: 124244, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38810681

RESUMO

This study assessed the spatial variability of PM2.5 source contributions across ten sites located in the South Coast Air Basin, California. Eight pollution sources and their contributions were obtained using positive matrix factorization (PMF) from the PM2.5 compositional data collected during the two sampling campaigns (2012/13 and 2018/19) of the Multiple Air Toxics Exposure Study (MATES). The identified sources were "gasoline vehicles", "aged sea salt", "biomass burning", "secondary nitrate", "secondary sulfate", "diesel vehicles", "soil/road dust" and "OP-rich". Among them, "gasoline vehicle" was the largest contributor to the PM2.5 mass. The spatial distributions of source contributions to PM2.5 at the sites were characterized by the Pearson correlation coefficients as well as coefficients of determination and divergence. The highest spatial variability was found for the contributions from the "OP-rich" source in both MATES campaigns suggesting varying influences of the wildfires in the Los Angeles Basin. Alternatively, the smallest spatial variabilities were observed for the contributions of the "secondary sulfate" and "aged sea salt" sources resolved for the MATES campaign in 2012/13. The "soil/road dust" contributions of the sites from the 2018/19 campaign were also highly correlated. Compared to the other sites, the source contribution patterns observed for Inland Valley and Rubidoux were the most diverse from the others likely due to their remote locations from the other sites, the major urban area, and the Pacific Ocean.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Monitoramento Ambiental , Material Particulado , Los Angeles , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Material Particulado/análise , Emissões de Veículos/análise
5.
Circulation ; 149(15): e1067-e1089, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38436070

RESUMO

Nearly 56% of the global population lives in cities, with this number expected to increase to 6.6 billion or >70% of the world's population by 2050. Given that cardiometabolic diseases are the leading causes of morbidity and mortality in people living in urban areas, transforming cities and urban provisioning systems (or urban systems) toward health, equity, and economic productivity can enable the dual attainment of climate and health goals. Seven urban provisioning systems that provide food, energy, mobility-connectivity, housing, green infrastructure, water management, and waste management lie at the core of human health, well-being, and sustainability. These provisioning systems transcend city boundaries (eg, demand for food, water, or energy is met by transboundary supply); thus, transforming the entire system is a larger construct than local urban environments. Poorly designed urban provisioning systems are starkly evident worldwide, resulting in unprecedented exposures to adverse cardiometabolic risk factors, including limited physical activity, lack of access to heart-healthy diets, and reduced access to greenery and beneficial social interactions. Transforming urban systems with a cardiometabolic health-first approach could be accomplished through integrated spatial planning, along with addressing current gaps in key urban provisioning systems. Such an approach will help mitigate undesirable environmental exposures and improve cardiovascular and metabolic health while improving planetary health. The purposes of this American Heart Association policy statement are to present a conceptual framework, summarize the evidence base, and outline policy principles for transforming key urban provisioning systems to heart-health and sustainability outcomes.


Assuntos
American Heart Association , Doenças Cardiovasculares , Humanos , Cidades , Exposição Ambiental , Políticas , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle
6.
Nat Food ; 5(3): 251-261, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38486126

RESUMO

Food consumption contributes to the degradation of air quality in regions where food is produced, creating a contrast between the health burden caused by a specific population through its food consumption and that faced by this same population as a consequence of food production activities. Here we explore this inequality within China's food system by linking air-pollution-related health burden from production to consumption, at high levels of spatial and sectorial granularity. We find that low-income groups bear a 70% higher air-pollution-related health burden from food production than from food consumption, while high-income groups benefit from a 29% lower health burden relative to their food consumption. This discrepancy largely stems from a concentration of low-income residents in food production areas, exposed to higher emissions from agriculture. Comprehensive interventions targeting both production and consumption sides can effectively reduce health damages and concurrently mitigate associated inequalities, while singular interventions exhibit limited efficacy.


Assuntos
Poluição do Ar , Renda , Pobreza , Alimentos , Agricultura
7.
Environ Int ; 183: 108382, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38103346

RESUMO

Studies in mice and older, subfertile women have found that air pollution exposure may compromise female reproduction. Our objective was to evaluate the effects of air pollution on ovarian reserve and outcomes of ovarian stimulation among young, healthy females. We included 472 oocyte donors who underwent 781 ovarian stimulation cycles at a fertility clinic in Atlanta, Georgia, USA (2008-2019). Antral follicle count (AFC) was assessed with transvaginal ultrasonography and total and mature oocyte count was assessed following oocyte retrieval. Ovarian sensitivity index (OSI) was calculated as the total number of oocytes divided by total gonadotrophin dose × 1000. Daily ambient exposure to nitric oxide (NOx), carbon monoxide (CO), and particulate matter ≤ 2.5 (PM2.5) was estimated using a fused regional + line-source model for near-surface releases at a 250 m resolution based on residential address. Generalized estimating equations were used to evaluate the associations of an interquartile range (IQR) increase in pollutant exposure with outcomes adjusted for donor characteristics, census-level poverty, and meteorological factors. The median (IQR) age among oocyte donors was 25.0 (5.0) years, and 31% of the donors were racial/ethnic minorities. The median (IQR) exposure to NOx, CO, and PM2.5 in the 3 months prior to stimulation was 37.7 (32.0) ppb, 612 (317) ppb, and 9.8 (2.9) µg/m3, respectively. Ambient air pollution exposure in the 3 months before AFC was not associated with AFC. An IQR increase in PM2.5 in the 3 months before AFC and during stimulation was associated with -7.5% (95% CI -14.1, -0.4) and -6.4% (95% CI -11.0, -1.6) fewer mature oocytes, and a -1.9 (95% CI -3.2, -0.5) and -1.0 (95% CI -1.8, -0.2) lower OSI, respectively. Our results suggest that lowering the current 24-h PM2.5 standard in the US to 25 µg/m3 may still not adequately protect against the reprotoxic effects of short-term PM2.5 exposure.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Infertilidade , Reserva Ovariana , Adulto , Feminino , Humanos , Poluentes Atmosféricos/toxicidade , Oócitos , Material Particulado/toxicidade , Adulto Jovem
8.
Sci Total Environ ; 904: 166184, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37586514

RESUMO

The Hg research community needs methods to more accurately measure atmospheric Hg concentrations and chemistry. The Reactive Mercury Active System (RMAS) uses cation exchange, nylon, and PTFE membranes to determine reactive mercury (RM), gaseous oxidized mercury, and particulate-bound mercury (PBM) concentrations and chemistry. New data for Atlanta, Georgia (NRGT) demonstrated that particulate-bound Hg was dominant and the chemistry was primarily N and S HgII compounds. At Great Salt Lake, Utah (GSL), RM was predominately PBM, with NS > organics > halogen > O HgII compounds. At Guadalupe Mountains National Park, Texas (GUMO), halogenated compound concentrations were lowest when air interacting with the site was primarily derived from the Midwest, and highest when the air was sourced from Mexico. At Amsterdam Island, Southern Indian Ocean, compounds were primarily halogenated with some N, S, and organic HgII compounds potentially associated with biological activity. The GEOS-Chem model was applied to see if it predicted measurements at five field sites. Model values were higher than observations at GSL, slightly lower at NRGT, and observations were an order of magnitude higher than modeled values for GUMO and Reno, Nevada. In general, data collected from 13 locations indicated that N, S, and organic RM compounds were associated with city and forest locations, halogenated compounds were sourced from the marine boundary layer, and O compounds were associated with long-range transport. Data being developed currently, and in the past, suggest there are multiple forms of RM that modelers must consider, and PBM is an important component of RM.

9.
Sci Total Environ ; 891: 164464, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37247741

RESUMO

The chemical composition of PM2.5 has a significant impact on human health and air quality, and its accurate knowledge can be used to identify contributing emission sources. Assessing and quantifying the impacts of various factors (e.g., emissions, meteorology, and large-scale climate patterns) on the main PM2.5 chemical components can give guidance for implementing effective regulations to improve air quality in the future. In this study, we developed generalized additive models (GAMs) to assess how emissions, meteorological factors, and large-scale climate indices affected ammonium, sulfate, nitrate, elemental carbon, and organic carbon from 2002 to 2019 in the South Coast Air Basin (SoCAB). Concentration trends from three sites in the SoCAB are studied. The statistical results showed that GAMs can capture the variability of these species' daily concentrations (R2 = 0.6 to 0.7) and annual concentrations (R2 = 0.93 to 0.99). Precursor emissions most significantly affect PM2.5 species production, though meteorological factors like maximum temperature, relative humidity, wind speed, and boundary layer height, also influence PM2.5 composition. In the future, these meteorological factors will become more significant in affecting PM2.5 speciation, although emissions will continue to strongly affect formation. Results show that the composition of most PM2.5 species will decrease in the future except for OC, which will become the largest contributor to PM2.5.

10.
J Air Waste Manag Assoc ; 73(5): 374-393, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37171913

RESUMO

Following the outbreak of the COVID-19 pandemic, several papers have examined the effect of the pandemic response on urban air pollution worldwide. This study uses observed traffic volume and near-road air pollution data for black carbon (BC), oxides of nitrogen (NOx), and carbon monoxide (CO) to estimate the emissions contributions of light-duty and heavy-duty diesel vehicles in five cities in the continental United States. Analysis of mobile source impacts in the near-road environment has several health and environmental justice implications. Data from the initial COVID-19 response period, defined as March to May in 2020, were used with data from the same period over the previous two years to develop general additive models (GAMs) to quantify the emissions impact of each vehicle class. The model estimated that light-duty traffic contributes 4-69%, 14-65%, and 21-97% of BC, NOx, and CO near-road levels, respectively. Heavy-duty diesel traffic contributes an estimated 26-46%, 17-63%, and -7-18% of near-road levels of the three pollutants. The estimated mobile source impacts were used to calculate NOx to CO and BC to NOx emission ratios, which were between 0.21-0.32 µg m-3 NOx (µg m-3 CO)-1 and 0.013-0.018 µg m-3 BC (µg m-3 NOx)-1. These ratios can be used to assess existing emission inventories for use in determining air pollution standards. These results agree moderately well with recent National Emissions Inventory estimates and other empirically-derived estimates, showing similar trends among the pollutants. However, a limitation of this study was the recurring presence of an implausible air pollution impact estimate in 41% of the site-pollutant combinations, where a vehicle class was estimated to account for either a negative impact or an impact higher than the total estimated pollutant concentration. The variations seen in the GAM estimates are likely a result of location-specific factors, including fleet composition, external pollution sources, and traffic volumes.Implications: Drastic reductions in traffic and air pollution during the lockdowns of the COVID-19 pandemic present a unique opportunity to assess vehicle emissions. A General Additive Modeling approach is developed to relate traffic levels, observed air pollution, and meteorology to identify the amount vehicle types contribute to near-road levels of traffic-related air pollutants (TRAPs), which is important for future emission regulation and policy, given the significant health and environmental justice implications of vehicle-related pollution along major roadways. The model is used to evaluate emission inventories in the near-road environment, which can be used to refine existing estimates. By developing a locally data-driven method to readily characterize impacts and distinguish between heavy and light duty vehicle effects, local regulations can be used to target policies in major cities around the country, thus addressing local health disbenefits and disparities occurring as a result of exposure to near-road air pollution.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Ambientais , Humanos , Poluentes Atmosféricos/análise , Material Particulado/análise , Pandemias , Monitoramento Ambiental/métodos , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Poluição do Ar/análise , Emissões de Veículos/análise , Poluentes Ambientais/análise , Fuligem/análise
11.
J Hazard Mater ; 456: 131655, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37216807

RESUMO

Nitrate is formed through the chemical production of gas-phase nitric acid and subsequent partitioning to the aerosol phase during the daytime. Many studies in the past separated these two aspects, even though they occur simultaneously in the atmosphere. To better understand the nitrate formation mechanism and effectively mitigate its production, it is necessary to consider the synergy between these two mechanisms. For this, we analyze hourly-speciated ambient observations data, with EK&TMA (Empirical Kinetic & Thermodynamic Modeling Approach) map to comprehensively explore the factors controlling nitrate production. Results show that precursor NO2 concentration and aerosol pH, which are related to anthropogenic activities, are the two major factors for chemical kinetics production and gas/particle thermodynamic partitioning processes respectively. Abundant NO2 and weakly acidic environments are favorable conditions for daytime particulate nitrate pollution, thus collaborative control of coal source, vehicle source, and dust source is needed to alleviate nitrate pollution.

12.
Environ Res ; 228: 115839, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37024035

RESUMO

BACKGROUND: Air pollution exposure is a significant risk factor for morbidity and mortality, especially for those with pre-existing chronic disease. Previous studies highlighted the risks that long-term particulate matter exposure has for readmissions. However, few studies have evaluated source and component specific associations particularly among vulnerable patient populations. OBJECTIVES: Use electronic health records from 5556 heart failure (HF) patients diagnosed between July 5, 2004 and December 31, 2010 that were part of the EPA CARES resource in conjunction with modeled source-specific fine particulate matter (PM2.5) to estimate the association between exposure to source and component apportioned PM2.5 at the time of HF diagnosis and 30-day readmissions. METHODS: We used zero-inflated mixed effects Poisson models with a random intercept for zip code to model associations while adjusting for age at diagnosis, year of diagnosis, race, sex, smoking status, and neighborhood socioeconomic status. We undertook several sensitivity analyses to explore the impact of geocoding precision and other factors on associations and expressed associations per interquartile range increase in exposures. RESULTS: We observed associations between 30-day readmissions and an interquartile range increase in gasoline- (16.9% increase; 95% confidence interval = 4.8%, 30.4%) and diesel-derived PM2.5 (9.9% increase; 95% confidence interval = 1.7%, 18.7%), and the secondary organic carbon component of PM2.5 (SOC; 20.4% increase; 95% confidence interval = 8.3%, 33.9%). Associations were stable in sensitivity analyses, and most consistently observed among Black study participants, those in lower income areas, and those diagnosed with HF at an earlier age. Concentration-response curves indicated a linear association for diesel and SOC. While there was some non-linearity in the gasoline concentration-response curve, only the linear component was associated with 30-day readmissions. DISCUSSION: There appear to be source specific associations between PM2.5 and 30-day readmissions particularly for traffic-related sources, potentially indicating unique toxicity of some sources for readmission risks that should be further explored.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Insuficiência Cardíaca , Humanos , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Readmissão do Paciente , Exposição Ambiental/análise , Gasolina , Material Particulado/análise , Poluição do Ar/análise , Insuficiência Cardíaca/epidemiologia
13.
ACS Nano ; 17(9): 8345-8354, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37075195

RESUMO

High energy consumption and high cost have been the obstacles for large-scale deployment of all state-of-the-art CO2 capture technologies. Finding a transformational way to improve mass transfer and reaction kinetics of the CO2 capture process is timely for reducing carbon footprints. In this work, commercial single-walled carbon nanotubes (CNTs) were activated with nitric acid and urea under ultrasonication and hydrothermal methods, respectively, to prepare N-doped CNTs with the functional group of -COOH, which possesses both basic and acid functionalities. The chemically modified CNTs with a concentration of 300 ppm universally catalyze both CO2 sorption and desorption of the CO2 capture process. The increases in the desorption rate achieved with the chemically modified CNTs can reach as high as 503% compared to that of the sorbent without the catalyst. A chemical mechanism underlying the catalytic CO2 capture is proposed based on the experimental results and further confirmed by density functional theory computations.

14.
Environ Health Perspect ; 131(4): 47003, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37011135

RESUMO

BACKGROUND: Previous studies of short-term ambient air pollution exposure and asthma morbidity in the United States have been limited to a small number of cities and/or pollutants and with limited consideration of effects across ages. OBJECTIVES: To estimate acute age group-specific effects of fine and coarse particulate matter (PM), major PM components, and gaseous pollutants on emergency department (ED) visits for asthma during 2005-2014 across the United States. METHODS: We acquired ED visit and air quality data in regions surrounding 53 speciation sites in 10 states. We used quasi-Poisson log-linear time-series models with unconstrained distributed exposure lags to estimate site-specific acute effects of air pollution on asthma ED visits overall and by age group (1-4, 5-17, 18-49, 50-64, and 65+ y), controlling for meteorology, time trends, and influenza activity. We then used a Bayesian hierarchical model to estimate pooled associations from site-specific associations. RESULTS: Our analysis included 3.19 million asthma ED visits. We observed positive associations for multiday cumulative exposure to all air pollutants examined [e.g., 8-d exposure to PM2.5: rate ratio of 1.016 with 95% credible interval (CI) of (1.008, 1.025) per 6.3-µg/m3 increase, PM10-2.5: 1.014 (95% CI: 1.007, 1.020) per 9.6-µg/m3 increase, organic carbon: 1.016 (95% CI: 1.009, 1.024) per 2.8-µg/m3 increase, and ozone: 1.008 (95% CI: 0.995, 1.022) per 0.02-ppm increase]. PM2.5 and ozone showed stronger effects at shorter lags, whereas associations of traffic-related pollutants (e.g., elemental carbon and oxides of nitrogen) were generally stronger at longer lags. Most pollutants had more pronounced effects on children (<18 y old) than adults; PM2.5 had strong effects on both children and the elderly (>64 y old); and ozone had stronger effects on adults than children. CONCLUSIONS: We reported positive associations between short-term air pollution exposure and increased rates of asthma ED visits. We found that air pollution exposure posed a higher risk for children and older populations. https://doi.org/10.1289/EHP11661.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Asma , Poluentes Ambientais , Ozônio , Criança , Adulto , Humanos , Estados Unidos/epidemiologia , Idoso , Teorema de Bayes , Poluição do Ar/análise , Poluentes Atmosféricos/análise , Asma/epidemiologia , Material Particulado/análise , Ozônio/análise , Serviço Hospitalar de Emergência
15.
Chemosphere ; 325: 138385, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36921775

RESUMO

Annual fine particulate matter (PM2.5) mass concentrations in the South Coast Air Basin (SoCAB) of California decreased from around 30 µg/m3 to 11 µg/m3 between 2000 and 2013 but rose from 11 µg/m3 to 13 µg/m3 between 2014 and 2018, raising important questions about the effectiveness of ongoing emission control policies. A two-step generalized additive model (GAM)-least squares approach was developed to explore the effects of emissions, large-scale climate events and meteorological factors on daily PM2.5 mass concentrations from 2000 to 2019 to quantitatively link impacts of emissions and meteorological on PM2.5 and to assess factors leading to the increase. The GAM had an R2 = 0.99 and root mean square error (RMSE) = 0.7 µg/m3 for the annual average PM2.5 concentrations. The two-step method had an R2 = 0.93 and RMSE = 4.07 µg/m3 for the 98th percentile 24-hr average PM2.5 concentrations. Variations in both emissions and relative humidity were of high importance compared with other included factors. Interactions of NH3 emissions with NOx and SO2 emissions, which lead to ammonium nitrate and sulfate aerosol formation, were the most important factors. Meteorological effects on PM2.5 explained the majority of the daily PM2.5 fluctuations. Emission changes (increases in SO2 and PM2.5) led to increases in predicted PM2.5 between 2014 and 2018. Predicted future PM2.5, using projected emissions and meteorological data from model simulations of representative concentration pathway (RCP) scenarios, are around 12 µg/m3 (annual) and 30 µg/m3 (98th percentile daily), which are both close to the current National Ambient Air Quality Standards (NAAQS) for PM2.5. Meteorological impacts on the predicted PM2.5 in future years lead to variations of ±2 µg/m3 for the annual average and ±5 µg/m3 for the 98th percentile daily level. Future climate changes lead to a probable year-to-year variation that will let PM2.5 levels in some years exceed the standard.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Material Particulado/análise , Nitratos , California , Monitoramento Ambiental/métodos
17.
Proc Natl Acad Sci U S A ; 120(1): e2211282119, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36574646

RESUMO

Growing evidence suggests that fine particulate matter (PM2.5) likely increases the risks of dementia, yet little is known about the relative contributions of different constituents. Here, we conducted a nationwide population-based cohort study (2000 to 2017) by integrating the Medicare Chronic Conditions Warehouse database and two independently sourced datasets of high-resolution PM2.5 major chemical composition, including black carbon (BC), organic matter (OM), nitrate (NO3-), sulfate (SO42-), ammonium (NH4+), and soil dust (DUST). To investigate the impact of long-term exposure to PM2.5 constituents on incident all-cause dementia and Alzheimer's disease (AD), hazard ratios for dementia and AD were estimated using Cox proportional hazards models, and penalized splines were used to evaluate potential nonlinear concentration-response (C-R) relationships. Results using two exposure datasets consistently indicated higher rates of incident dementia and AD for an increased exposure to PM2.5 and its major constituents. An interquartile range increase in PM2.5 mass was associated with a 6 to 7% increase in dementia incidence and a 9% increase in AD incidence. For different PM2.5 constituents, associations remained significant for BC, OM, SO42-, and NH4+ for both end points (even after adjustments of other constituents), among which BC and SO42- showed the strongest associations. All constituents had largely linear C-R relationships in the low exposure range, but most tailed off at higher exposure concentrations. Our findings suggest that long-term exposure to PM2.5 is significantly associated with higher rates of incident dementia and AD and that SO42-, BC, and OM related to traffic and fossil fuel combustion might drive the observed associations.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Demência , Humanos , Idoso , Estados Unidos/epidemiologia , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Estudos de Coortes , Medicare , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Material Particulado/efeitos adversos , Material Particulado/análise , Poeira , Demência/induzido quimicamente , Demência/epidemiologia , Exposição Ambiental/efeitos adversos , China
18.
Adv Sci (Weinh) ; 10(3): e2205352, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36416301

RESUMO

Ionic liquids (ILs) have been used for carbon dioxide (CO2 ) capture, however, which have never been used as catalysts to accelerate CO2 capture. The record is broken by a uniquely designed IL, [EMmim][NTf2 ]. The IL can universally catalyze both CO2 sorption and desorption of all the chemisorption-based technologies. As demonstrated in monoethanolamine (MEA) based CO2 capture, even with the addition of only 2000 ppm IL catalyst, the rate of CO2 desorption-the key to reducing the overall CO2 capture energy consumption or breaking the bottleneck of the state-of-the-art technologies and Paris Agreement implementation-can be increased by 791% at 85 °C, which makes use of low-temperature waste heat and avoids secondary pollution during CO2 capture feasible. Furthermore, the catalytic CO2 capture mechanism is experimentally and theoretically revealed.

20.
Sci Bull (Beijing) ; 67(20): 2124-2138, 2022 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-36546112

RESUMO

Ammonia, primarily made with Haber-Bosch process developed in 1909 and winning two Nobel prizes, is a promising noncarbon fuel for preventing global warming of 1.5 °C above pre-industrial levels. However, the undesired characteristics of the process, including high carbon footprint, necessitate alternative ammonia synthesis methods, and among them is chemical looping ammonia production (CLAP) that uses nitrogen carrier materials and operates at atmospheric pressure with high product selectivity and energy efficiency. To date, neither a systematic review nor a perspective in nitrogen carriers and CLAP has been reported in the critical area. Thus, this work not only assesses the previous results of CLAP but also provides perspectives towards the future of CLAP. It classifies, characterizes, and holistically analyzes the fundamentally different CLAP pathways and discusses the ways of further improving the CLAP performance with the assistance of plasma technology and artificial intelligence (AI).


Assuntos
Amônia , Inteligência Artificial , Nitrogênio/química
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