LitSearch-NOx (2024)

Project ID

4767

Category

NAAQS

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April 12, 2023, 4:32 a.m.

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Journal Article

Abstract  Urbanization growth and aging infrastructures necessitate new infrastructure construction projects in congested urban areas. Urban construction projects interrupt the regular on-road vehicle traffic flow that affects air pollution concentration in the adjacent areas. The project schedule, however, is a possible contributor to the air pollution which has been neglected to date. This research proposes a new framework to account for the impact of different urban project schedule alternatives on air pollution emission near the construction zones. The proposed framework uses the capabilities of vehicle traffic simulation to evaluate air pollution emission of different construction schedule alternatives and reduce the resulting emission in urban construction projects. The capability of the proposed framework is verified in a real grade separation case. Pollution concentration shows a potential reduction of up to 41% in sensitive locations. The achieved resulting values represent potential emission reduction of 7.8% for CO2, 8.2% for NOx, and 3.8% for PM10. The achieved results in the case study confirm the impact of the construction schedule on the air pollution emission throughout the project’s construction. It justifies the application of the framework in the congested urban areas. The proposed framework in the research contributes to the sustainable improvement of urban infrastructure projects.

Journal Article

Abstract  Introduction Metabolic syndrome (MetS) is a cluster of interrelated risk factors, which increase the risk of cardiovascular disease (CVD) and cancer. The prevalence of MetS might be affected by environmental pollution and individual’s poor lifestyles. Methods In this cross-sectional study, we aimed to evaluate the interactions effect of PAHs exposure and poor lifestyles on MetS among coke oven workers. We measured the concentrations of 11 urinary PAH metabolites among 682 coke oven workers by HPLC-MS. China adult blood lipid abnormality prevention guide (2016) was employed for diagnosing MetS. An interaction effect was tested in the modified Poisson regression models. Results The results showed that the urinary level of 1-NAP (P for trend = 0.043) and 2-FLU (P for trend = 0.037) had significant dose-response relationships with increased PR of MetS. For 1-NAP, statistically significant positive association was with low HDL among individuals (P for trend = 0.003). Besides, smoking was associated with a significantly increased risk of prevalence ratio of MetS (PR = 1.07; 95% CI 1.00–1.13), high triglycerides (PR = 1.13; 95% CI 1.05–1.20) and low HDL (PR = 1.07; 95% CI 1.01–1.14). Smokers who with high levels of 1-NAP and 2-FLU had higher prevalence ratio of MetS compared with non-smokers who with low levels of 1-NAP [PR (95% CI): 1.17 (1.06–1.29); P for trend = 0.002] and 2-FLU [PR (95% CI): 1.17 (1.06–1.29); P for trend = 0.004]. Conclusions Our findings suggested PAHs exposure increased the prevalence ratio of MetS and this effect can be modified by smoking status.

Journal Article

Abstract  Preeclampsia (PE) is a complication of pregnancy characterized by hypertension (HTN-Preg), and often proteinuria. If not managed promptly, PE could lead to eclampsia and seizures. PE could also lead to intrauterine growth restriction (IUGR) and prematurity at birth. Although PE is a major cause of maternal and fetal morbidity and mortality, the underlying mechanisms are unclear. Also, there is a wide variability in the incidence of PE, ranging between 2 and 8% of pregnancies in the Eastern, Western and Developing world, suggesting regional differences in the risk factors and predictors of the pregnancy-related disorder. Several demographic, genetic, dietary and environmental factors, as well as maternal circulating biomarkers have been associated with PE. Demographic factors such as maternal race and ethnicity could play a role in PE. Specific genetic polymorphisms have been identified in PE. Maternal age, parity, education and socioeconomic status could be involved in PE. Dietary fat, protein, calcium and vitamins, body weight, and environmental factors including climate changes and air pollutants could also play a role in PE. Several circulating cytoactive factors including anti-angiogenic factors and cytokines have also been associated with PE. Traditional midwifery care is a common practice in local maternity care units, while advanced perinatal care and new diagnostic tools such as uterine artery Doppler velocimetry have been useful in predicting early PE in major medical centers. These PE risk factors, early predictors and diagnostic tools vary vastly in different regions of the Eastern, Western and Developing world. Further understanding of the differences in the demographic, genetic, dietary and environmental factors among pregnant women in different world regions should help in designing a region-specific cluster of risk factors and predictors of PE, and in turn provide better guidance for region-specific tools for early detection and management of PE. © 2020 Elsevier Inc.

Journal Article

Abstract  Neutrophils were traditionally considered as short-lived cells with abundant secretory and protein synthetic activity. Recent studies, however, indicate neutrophils are in reality a heterogeneous population of cells. Neutrophils differentiate from pluripotent stem cells in the bone marrow, and can further mature in the blood stream and can have different phenotypes in health and disease conditions. Neutrophils undergo primary functions such as phagocytosis, production of reactive oxygen species (ROS), release of lipid mediators and inflammatory proteins (mainly cytokines), and apoptosis. Neutrophils stimulate other neutrophils and trigger a cascade of immune and inflammatory responses. The underpinning intracellular metabolisms that support these neutrophil functions are herein reported. It has been known for many decades that neutrophils utilize glucose as a primary fuel and produce lactate as an end product of glycolysis. Neutrophils metabolize glucose through glycolysis and the pentose- phosphate pathway (PPP). Mitochondrial glucose oxidation is very low. The PPP provides the reduced nicotinamide adenine dinucleotide phosphate (NADPH) for the NADPH-oxidase (NOX) complex activity to produce superoxide from oxygen. These cells also utilize glutamine and fatty acids to produce the required adenosine triphosphate (ATP) and precursors for the synthesis of molecules that trigger functional outcomes. Neutrophils obtained from rat intraperitoneal cavity and incubate for 1 hour at 37°C metabolize glutamine at higher rate than that of glucose. Glutamine delays neutrophil apoptosis and maintains optimal NOX activity for superoxide production. Under limited glucose provision, neutrophils move to fatty acid oxidation (FAO) to obtain the required energy for the cell function. FAO is mainly associated with neutrophil differentiation and maturation. Hypoxia, hormonal dysfunction, and physical exercise markedly change neutrophil metabolism. It is now become clear that neutrophil metabolism underlies the heterogeneity of neutrophil phenotypes and should be intense focus of investigation.

Journal Article

Abstract  According to the World Health Organization (WHO) air pollution in urban areas, mainly associated with inhalation of gaseous pollutants and particulate matter emitted from motor vehicles, is responsible for one million deaths per year. Carbon monoxide (CO) from the incomplete combustion of fuel is known to bind with hemoglobin, decreasing the blood oxygen-delivery and inducing tissues hypoxia; being more pronounced under conditions of stress like physical activity. The present study demonstrates the usefulness of a compact CO sensor (Alphasense CO-B4) mounted on a bicycle to evaluate atmospheric levels of CO associated with urban microenvironments within a growing Australian city (Brisbane). Urban bike pathways show pronounced and significant variations in air quality according to the surrounding microenvironment and the time of day. The inhaled dose in real time and the CO total dose over each trip were valuable for estimating the air quality of the route, and identifed how the health benefits of riding a bicycle could be partially offset by poor air quality depending on where and when a cycle route is taken in the inner-city. Finally, environmental conditions, such as wind speed, were found to significantly affected atmospheric CO concentrations, at least during the study period. The present work provides information regarding commuters' exposure to atmospheric pollutants, necessary for modifying the population's (including cyclists) perception of pollution in the urban environment, providing people with the opportunity to choose a healthier route.

Journal Article

Abstract  This paper reports upon and analyses vehicle emissions measured by the Emissions Detecting and Reporting (EDAR) system, a Vehicle Emissions Remote Sensing System (VERSS) type device, used in five UK based field campaigns in 2016 and 2017. In total 94,940 measurements were made of 75,622 individual vehicles during the five campaigns. The measurements are subset into vehicle type (bus, car, HGV, minibus, motorcycle, other, plant, taxi, van, and unknown), fuel type for car (petrol and diesel), and EURO class, and particulate matter (PM), nitric oxide (NO) and nitrogen dioxide (NO2) are reported. In terms of recent EURO class emission trends, NO and NOx emissions decrease from EURO 5 to EURO 6 for nearly all vehicle categories. Interestingly, taxis show a marked increase in NO2 emissions from EURO 5 to EURO 6. Perhaps most concerningly is a marked increase in PM emissions from EURO 5 to EURO 6 for HGVs. Another noteworthy observation was that vans, buses and HGVs of unknown EURO class were often the dirtiest vehicles in their classes, suggesting that where counts of such vehicles are high, they will likely make a significant contribution to local emissions. Using Vehicle Specific Power (VSP) weighting we provide an indication of the magnitude of the on-site VERSS bias and also a closer estimate of the regulatory test/on-road emissions differences. Finally, a new ‘EURO Updating Potential’ (EUP) factor is introduced, to assess the effect of a range of air pollutant emissions restricted zones either currently in use or marked for future introduction. In particular, the effects of the London based Low Emission Zone (LEZ) and Ultra-Low Emissions Zone (ULEZ), and the proposed Birmingham based Clean Air Zone (CAZ) are estimated. With the current vehicle fleet, the impacts of the ULEZ and CAZ will be far more significant than the LEZ, which was introduced in 2008.

Journal Article

Abstract  While road network expansion is crucial for economic development, it can cause a notable disturbance of fauna, especially in protected area in terms of habitat fragmentation, risk of collision, and also indirect threat such as pollution. In this study, we monitored the 4.6-km long tarmac road crossing the Kibale National Park in Uganda, home to a rich variety of wild species including the endangered chimpanzees. We evaluated the effects of collisions and pollution, as well as the impact of the renovation process in terms of disturbance and the mitigation measures deployed. This survey reports the death of 24 wild animals killed by cars, including two chimpanzees. The atmospheric concentrations of O-3, NO2, SO2, and BTEX did not exceed recommended limits. More than 5000 plastic bottles were collected along the road within 4 months, and for the first time, the presence of BPA and BPS was detected in the hairs of wild chimpanzees. The road bisecting the Kibale National Park poses a high danger in terms of traffic and an underestimated risk related to plastic pollution. Measures (signpost, speed bumps) should be urgently deployed to decrease the risk posed by the renovated road for emblematic species such as chimpanzees, which are crucial for tourism and economy in Uganda.

Journal Article

Abstract  The developmental exposure to a single chemical may elicit apoptosis in the different fetal organs, while the combined effects are restricted. We have examined the protective role of flaxseed (FS) against diesel exhaust particles (DEPs)- and/or fenitrothion (FNT)-induced fetal cardiac oxidative stress and apoptosis. A total of 48 timed pregnant rats were divided into eight groups (n = 6). The first group was saved as the control and the second fed on 20% FS diet. Animals in the third, fourth, and fifth groups were administered with DEPs (2.0 mg/kg), FNT (3.76 mg/kg), and their combination, respectively, while the sixth, seventh, and eighth groups were supplemented with 20% FS through intoxication with DEPs, FNT, and their combination, respectively. Our results revealed that DEPs and/or FNT significantly elevated the level of protein carbonyl and superoxide dismutase activity in the fetal cardiac tissues. However, the catalase activity and total thiol level were decreased; besides the histopathological alterations were remarked. Moreover, DEPs and/or FNT exhibited significant down-regulation in the anti-apoptotic (Bcl-2) and paraoxonase-1 gene expression, and up-regulation in the apoptotic (Bax and caspase-3) gene expression along with DNA fragmentation. Remarkably, FS supplementation significantly ameliorated the fetal cardiac oxidative injury, down-regulated the expression of the apoptotic genes, up-regulated the anti-apoptotic and paraoxonase-1 gene expression, reduced DNA fragmentation, and alleviated the myocardial cell architectures. These findings revealed that FS attenuates DEPs- and/or FNT-induced apoptotic cell death by repairing the disturbance in the anti-apoptotic/pro-apoptotic gene balance toward cell survival in the fetal myocardial cells.

Journal Article

Abstract  Introduction: Motor vehicle exhaust is an important source of air pollutants and greenhouse gases. Concerns over the health and climate effects of mobile-source emissions have prompted worldwide efforts to reduce vehicle emissions. Implementation of more stringent emission standards have driven advances in vehicle, engine, and exhaust after-treatment technologies as well as fuel formulations. On the other hand, vehicle numbers and travel distances have been increasing because of population and economic growth and changes in land use. These factors have resulted in changes to the amount and chemical composition of vehicle emissions. Roadway tunnel studies are a practical way to characterize real-world emissions from the on-road vehicle fleet in an environment isolated from other combustion pollution sources. Measurements in the same tunnel over time allow evaluation of vehicle emission changes and the effectiveness of emission reduction measures. Tunnel studies estimate the impacts of vehicle emissions on air quality and traffic-related exposures, generate source profile inputs for receptor-oriented source apportionment models, provide data to evaluate emission models, and serve as a baseline for future comparisons. The present study characterized motor vehicle emission factors and compositions in two roadway tunnels that were first studied over a decade ago. The specific aims were to (1) quantify current fleet air pollutant emission factors, (2) evaluate emission change over time, (3) establish source profiles for volatile organic compounds (VOCs) and particulate matter ≤2.5 μm in aerodynamic diameter (PM2.5), (4) estimate contributions of fleet components and non-tailpipe emissions to VOCs and PM2.5, and (5) evaluate the performance of the latest versions of mobile-source emission models (i.e., the EMission FACtors vehicle emission model used in Hong Kong [EMFAC-HK] and the MOtor Vehicle Emission Simulator used in the United States [MOVES]). Methods: Measurements were conducted in the Shing Mun Tunnel (SMT) in Hong Kong and the Fort McHenry Tunnel (FMT) in Baltimore, Maryland, in the United States, representing the different fleet compositions, emission controls, fuels, and near-road exposure levels found in Hong Kong and the United States. These tunnels have extensive databases acquired in 2003-2004 for the SMT and 1992 for the FMT. The SMT sampling was conducted during the period from 1/19/2015 to 3/31/2015, and the FMT sampling occurred during the periods from 2/8/2015 to 2/15/2015 (winter) and 7/31/2015 to 8/7/2015 (summer). Concentrations of criteria pollutants (e.g., carbon monoxide [CO], nitrogen oxides [NOx], and particulate matter [PM]) were measured in real time, and integrated samples of VOCs, carbonyls, polycyclic aromatic hydrocarbons (PAHs), and PM2.5 were collected in canisters and sampling media for off-line analyses. Emission factors were calculated from the tunnel measurements and compared with previous studies to evaluate emission changes over time. Emission contributions by different vehicle types were assessed by source apportionment modeling or linear regression. Vehicle emissions were modeled by EMFAC-HK version 3.3 and MOVES version 2014a for the SMT and the FMT, respectively, and compared with measured values. The influences of vehicle fleet composition and environmental parameters (i.e., temperature and relative humidity) on emissions were evaluated. Results: In the SMT, emissions of PM2.5, sulfur dioxide (SO2), and total non-methane hydrocarbons (NMHCs) markedly decreased from 2003-2004 to 2015: SO2 and PM2.5 were reduced by ~80%, and total NMHCs was reduced by ~44%. Emission factors of ethene and propene, key tracers for diesel vehicle (DV) emissions, decreased by ~65%. These reductions demonstrate the effectiveness of control measures, such as the implementation of low-sulfur fuel regulations and the phasing out of older DVs. However, the emission factors of isobutane and n-butane, markers for liquefied petroleum gas (LPG), increased by 32% and 17% between 2003-2004 and 2015, respectively, because the number of LPG vehicles increased. Nitrogen dioxide (NO2) to NOx volume ratios increased between 2003-2004 and 2015, indicating an increased NO2 fraction in primary exhaust emissions. Although geological mineral concentrations were similar between the 2003-2004 and 2015 studies, the contribution of geological materials to PM2.5 increased from 2% in 2003-2004 to 5% in 2015, signifying the continuing importance of non-tailpipe PM emissions as tailpipe emissions decrease. Emissions of CO, ammonia (NH3), nitric oxide (NO), NO2, and NOx, as well as carbonyls and PAHs in the SMT did not show statistically significant (at P < 0.05 based on Student's t-test) decreases from 2003-2004 to 2015. The reason for this is not clear and requires further investigation. A steady decrease in emissions of all measured pollutants during the past 23 years has been observed from tunnel studies in the United States, reflecting the effect of emission standards and new technologies that were introduced during this period. Emission reductions were more pronounced for the light-duty (LD) fleet than for the heavy-duty (HD) fleet. In comparison with the 1992 FMT study, the 2015 FMT study demonstrated marked reductions in LD emissions for all pollutants: emission factors for naphthalene were reduced the most, by 98%; benzene, toluene, ethylbenzene, and xylene (BTEX), by 94%; CO, NMHCs, and NOx, by 87%; and aldehydes by about 71%. Smaller reductions were observed for HD emission factors: naphthalene emissions were reduced by 95%, carbonyl emissions decreased by about 75%, BTEX by 60%, and NOx 58%. The 2015 fleet-average emission factors were higher in the SMT for CO, NOx, and summer PM2.5 than those in the FMT. The higher CO emissions in the SMT were possibly attributable to a larger fraction of motorcycles and LPG vehicles in the Hong Kong fleet. DVs in Hong Kong and the United States had similar emission factors for NOx. However, the non-diesel vehicles (NDVs), particularly LPG vehicles, had higher emission factors than those of gasoline cars, contributing to higher NOx emissions in the SMT. The higher PM2.5 emission factors in the SMT were probably attributable to there being more double-deck buses in Hong Kong. In both tunnels, PAHs were predominantly in the gas phase, with larger (four and more aromatic rings) PAHs mostly in the particulate phase. Formaldehyde, acetaldehyde, crotonaldehyde, and acetone were the most abundant carbonyl compounds in the SMT. In the FMT, the most abundant carbonyls were formaldehyde, acetone, acetaldehyde, and propionaldehyde. HD vehicles emitted about threefold more carbonyl compounds than LD vehicles did. In the SMT, the NMHC species were enriched with marker species for LPG (e.g., n-butane, isobutane, and propane) and gasoline fuel vapor (e.g., toluene, isopentane, and m/p-xylene), indicating evaporative losses. Source contributions to SMT PM2.5 mass were diesel exhaust (51.5 ± 1.8%), gasoline exhaust (10.0 ± 0.8%), LPG exhaust (5.0 ± 0.5%), secondary sulfate (19.9 ± 1.0%), secondary nitrate (6.3 ± 0.9%), and road dust (7.3 ± 1.3%). In the FMT, total NMHC emissions were 14% and 8% higher in winter than in summer for LD and HD vehicles, respectively. Elemental carbon (EC) and organic carbon (OC) were the major constituents of tunnel PM2.5. De-icing salt contributions to PM2.5 were observed in the FMT in winter. Emission estimates by the EMFAC-HK agreed with SMT measurements for CO2; the modeled emission factors for CO, NOx, and NMHCs were 1.5, 1.6, and 2.2 times the measurements, respectively; and the modeled emission factor for PM2.5 was 61% of the measured value in 2003. The EMFAC-HK estimates and SMT measurements for 2015 differed by less than 35%. The MOVES2014a model generally overestimated emissions of most of the pollutants measured in the FMT. No pollutants were significantly underestimated. The largest overestimation was observed for emissions measured during HD-rich driving conditions in winter. Conclusions: Significant reductions in SO2 and PM2.5 emissions between 2003 and 2015 were observed in the SMT, indicating the effectiveness of control measures on these two pollutants. The total NMHC emissions in the SMT were reduced by 44%, although isobutane and n-butane emissions increased because of the increase in the size of the LPG fleet. No significant reductions were observed for CO and NOx, results that differed from those for roadside ambient concentrations, emission inventory estimates, and EMFAC-HK estimates. In contrast, there was a steady decrease in emissions of most pollutants in the tunnels in the United States.

Journal Article

Abstract  ETHNOPHARMACOLOGICAL RELEVANCE: Eupafolin is a major bioactive compound derived from the methanolic extract of the medicinal herb Phyla nodiflora, which has been used in traditional Chinese medicine to treat various inflammatory diseases. Recently, particulate air pollutants have been shown to induce inflammation of the skin. In this study, we seek to determine whether eupafolin can inhibit the production of inflammatory mediators in a human skin keratinocyte cell line exposed to particulate air pollutants (particulate matter, PM), and determine the molecular mechanisms involved.

MATERIALS AND METHODS: Human keratinocyte HaCaT cells were treated with PM in the presence or absence of eupafolin. Cyclooxygenase-2 (COX-2) protein and gene expression levels were determined by Western blotting, RT-PCR and luciferase activity assay. Prostaglandin E2 (PGE2) production was evaluated by the enzyme immunoassay method. Generation of intracellular reactive oxygen species (ROS) was measured by the dichlorofluorescin (DCFH) oxidation assay, and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity was determined by a chemiluminescence assay. For in vivo studies, COX-2 expression in the skin of BALB/c nude mice was analyzed by immunohistochemistry.

RESULTS: Eupafolin inhibited PM-induced COX-2 protein and gene expression and PGE2 production in HaCaT cells. In addition, eupafolin suppressed PM-induced intracellular ROS generation, NADPH oxidase activity, MAPK (p38, JNK and ERK) activation and NK-κB activation. In vivo studies showed that topical treatment with eupafolin inhibited COX-2 expression in the epidermal keratinocytes of PM-treated mice.

CONCLUSIONS: Eupafolin exerts anti-inflammatory and antioxidant effects on skin keratinocytes exposed to particulate air pollutants, and may have potential use in the treatment or prevention of air pollutant-induced inflammatory skin diseases in the future.

Journal Article

Abstract  Here, we developed high-efficiency (>99.5%) polyimide-nanofiber air filters for the high temperature PM2.5 removal. The polyimide nanofibers exhibited high thermal stability, and the PM2.5 removal efficiency was kept unchanged when temperature ranged from 25-370 °C. These filters had high air flux with very low pressure drop. They could continuously work for >120 h for PM2.5 index >300. A field-test showed that they could effectively remove >99.5% PM particles from car exhaust at high temperature.

Journal Article

Abstract  Inhaled pollutants produce effects in virtually all organ systems in our body and have been linked to chronic diseases including hypertension, atherosclerosis, Alzheimer's and diabetes. A neurohormonal stress response (referred to here as a systemic response produced by activation of the sympathetic nervous system and hypothalamus-pituitary-adrenal (HPA)-axis) has been implicated in a variety of psychological and physical stresses, which involves immune and metabolic homeostatic mechanisms affecting all organs in the body. In this review, we provide new evidence for the involvement of this well-characterized neurohormonal stress response in mediating systemic and pulmonary effects of a prototypic air pollutant - ozone. A plethora of systemic metabolic and immune effects are induced in animals exposed to inhaled pollutants, which could result from increased circulating stress hormones. The release of adrenal-derived stress hormones in response to ozone exposure not only mediates systemic immune and metabolic responses, but by doing so, also modulates pulmonary injury and inflammation. With recurring pollutant exposures, these effects can contribute to multi-organ chronic conditions associated with air pollution. This review will cover, 1) the potential mechanisms by which air pollutants can initiate the relay of signals from respiratory tract to brain through trigeminal and vagus nerves, and activate stress responsive regions including hypothalamus; and 2) the contribution of sympathetic and HPA-axis activation in mediating systemic homeostatic metabolic and immune effects of ozone in various organs. The potential contribution of chronic environmental stress in cardiovascular, neurological, reproductive and metabolic diseases, and the knowledge gaps are also discussed. This article is part of a Special Issue entitled Air Pollution , edited by Wenjun Ding, Andy Ghio and Weidong Wu.

Journal Article

Abstract  The urban environment holds numerous emission sources for air and noise pollution, creating optimum conditions for environmental multi-exposure situations. Evaluation of the joint-exposure levels is the main obstacle for multi-exposure studies and one of the biggest challenges of the next decade. The present study aims to describe the noise/NO2 multi-exposure situations in the urban environment by exploring the possible discordant and concordant situations of both exposures. Fine-scale diffusion models were developed in the European medium-sized city of Besançon (France), and a classification method was used to evaluate the multi-exposure situations in the façade perimeter of 10,825 buildings. Although correlated (Pearson's r = 0.64, p < 0.01), urban spatial distributions of the noise and NO2 around buildings do not overlap, and 30% of the buildings were considered to be discordant in terms of the noise and NO2 exposure levels. This discrepancy is spatially structured and associated with variables describing the building's environment. Our results support the presence of several co-existing, multi-exposure situations across the city impacted by both the urban morphology and the emission and diffusion/propagation phases of each pollutant. Identifying the mechanisms of discrepancy and convergence of multi-exposure situations could help improve the health risk assessment and public health.

WoS
Journal Article

Abstract  Air pollution redn. scenarios regarding particulate matter 2.5 mu m, SO2, NOx, volatile org. compds., NH3 in European Union based on the integrated assessment model were presented. The role of health and environmental objectives to reduce the impacts of air pollution in Europe were explained. Addnl., the importance of emission scenarios as the baseline for EU emission redn. negotiations and agreements of air improvement policy and law regulations was shown.

Journal Article

Abstract  BACKGROUND: The impact of dust storms on human health has been studied in the context of Asian, Saharan, Arabian, and Australian storms, but there has been no recent population-level epidemiological research on the dust storms in North America. The relevance of dust storms to public health is likely to increase as extreme weather events are predicted to become more frequent with anticipated changes in climate through the 21st century.

OBJECTIVES: To examine the association between dust storms and county-level non-accidental mortality in the United States from 1993 through 2005.

METHODS: Dust storm incidence data, including date and approximate location, are taken from the U.S. National Weather Service storm database. County-level mortality data for the years 1993-2005 were acquired from the National Center for Health Statistics. Distributed lag conditional logistic regression models under a time-stratified case-crossover design were used to study the relationship between dust storms and daily mortality counts over the whole U.S. and in Arizona and California specifically. Endpoints included total non-accidental mortality and three mortality subgroups (cardiovascular, respiratory, and other non-accidental).

RESULTS: We estimated that for the US as a whole total non-accidental mortality increased by 7.4% (95% CI: 1.6, 13.5; p = 0.011) and 6.7% (95% CI: 1.1, 12.6; p = 0.018) at 2- and 3-day lags, respectively, and by an average of 2.7% (95% CI: 0.4, 5.1; p = 0.023) over lags 0-5 compared to referent days. Significant associations with non-accidental mortality were estimated for California (lag 2 and 0-5 day) and Arizona (lag 3), for cardiovascular mortality in the U.S. (lag 2) and Arizona (lag 3), and for other non-accidental mortality in California (lags 1-3 and 0-5.).

CONCLUSIONS: Dust storms are associated with increases in lagged non-accidental and cardiovascular mortality.

Journal Article

Abstract  With one-fifth of the world's total population, China's prevention and control of cardiovascular disease (CVD) may affect the success of worldwide efforts to achieve sustainable CVD reduction. Understanding China's current cardiovascular epidemic requires awareness of the economic development in the past decades. The rapid economic transformations (industrialization, marketization, urbanization, globalization, and informationalization) contributed to the aging demography, unhealthy lifestyles, and environmental changes. The latter have predisposed to increasing cardiovascular risk factors and the CVD pandemic. Rising CVD rates have had a major economic impact, which has challenged the healthcare system and the whole society. With recognition of the importance of health, initial political steps and national actions have been taken to address the CVD epidemic. Looking to the future, we recommend that 4 priorities should be taken: pursue multisectorial government and nongovernment strategies targeting the underlying causes of CVD (the whole-of-government and whole-of-society policy); give priority to prevention; reform the healthcare system to fit the nature of noncommunicable diseases; and conduct research for evidence-based, low-cost, simple, sustainable, and scalable interventions. By pursuing the 4 priorities, the pandemic of CVD and other major noncommunicable diseases in China will be reversed and the global sustainable development goal achieved.

Journal Article

Abstract  This study evaluated concentrations of main air pollutants in a Portuguese preschool (indoors/outdoors) environment, with emphasis on elemental characterization of different PM fractions, and estimated risks for the pupils (aged 3-5 years). With exception to total volatile organic compounds, levels of PM10, PM2.5, CO, CO2, and formaldehyde were below legislative guidelines. Calcium, sodium, aluminium, and potassium were the most abundant elements in indoor PM (82-84% of the analysed content) resulting mainly from crustal sources. Carcinogenic elements (1-2% of the indoor analysed content) were mostly PM2.5-bound (83-91%). Indoor-to-outdoor ratios of individual elements indicated contributions of indoor origin and from penetration of outdoor emissions indoors; trace metals were associated with ambient anthropogenic emissions (namely traffic). Non-carcinogenic and carcinogenic risks from overall preschool exposure were acceptable for children; for adults carcinogenic risks exceeded (4-11 times) the USEPA recommend value of 10(-6), being 8-40 times higher than for children.

Journal Article

Abstract  BACKGROUND: Researchers and policymakers are increasingly focused on combined exposures to social and environmental stressors, especially given how often these stressors tend to co-locate. Such exposures are equally relevant in urban and rural areas and may accrue disproportionately to particular communities or specific subpopulations.

OBJECTIVES: To estimate relationships between racial isolation (RI), a measure of the extent to which minority racial/ethnic group members are exposed to only one another, and long-term particulate matter with an aerodynamic diameter of <2.5μ (PM2.5) and ozone (O3) levels in urban and nonurban areas of the eastern two-thirds of the US.

METHODS: Long-term (5year average) census tract-level PM2.5 and O3 concentrations were calculated using output from a downscaler model (2002-2006). The downscaler uses a linear regression with additive and multiplicative bias coefficients to relate ambient monitoring data with gridded output from the Community Multi-scale Air Quality (CMAQ) model. A local, spatial measure of RI was calculated at the tract level, and tracts were classified by urbanicity, RI, and geographic region. We examined differences in estimated pollutant exposures by RI, urbanicity, and demographic subgroup (e.g., race/ethnicity, education, socioeconomic status, age), and used linear models to estimate associations between RI and air pollution levels in urban, suburban, and rural tracts.

RESULTS: High RI tracts (≥80th percentile) had higher average PM2.5 levels in each category of urbanicity compared to low RI tracts (<20th percentile), with the exception of the rural West. Patterns in O3 levels by urbanicity and RI differed by region. Linear models indicated that PM2.5 concentrations were significantly and positively associated with RI. The largest association between PM2.5 and RI was observed in the rural Midwest, where a one quintile increase in RI was associated with a 0.90μg/m(3) (95% confidence interval: 0.83, 0.99μg/m(3)) increase in PM2.5 concentration. Associations between O3 and RI in the Northeast, Midwest and West were positive and highest in suburban and rural tracts, even after controlling for potential confounders such as percentage in poverty.

CONCLUSION: RI is associated with higher 5year estimated PM2.5 concentrations in urban, suburban, and rural census tracts, adding to evidence that segregation is broadly associated with disparate air pollution exposures. Disproportionate burdens to adverse exposures such as air pollution may be a pathway to racial/ethnic disparities in health.

Journal Article

Abstract  The aim of this study was to link the concentrations of particulate matter with an aerodynamic diameter below 2.5 μm (PM2.5) and associated heavy metals with occurrence of wheezing and hospitalizations due to wheezing in 111 children who live near metallurgical plants in Targoviste City, Romania. A group of 72 children with high levels of immunoglobulin E (IgE) and eosinophils, as well as frequent wheezing episodes, was geolocated on digital thematic maps. Monitoring campaigns and medical assessments were performed over two consecutive years (2013-2014). The multiannual average concentrations of PM2.5 ranged from 4.6 to 22.5 μg m(-3), up to a maximum value of 102 μg m(-3). Significant correlations (p < 0.01) were observed between the locations of the children with respiratory issues and the PM2.5 multiannual average (r = 0.985) and PM2.5 maximum (r = 0.813). Fe, Ni, Cd, and Cr were the main marker elements of the emissions from steel production and metal-working facilities in the Targoviste area. The results support the hypothesis that increased PM2.5 levels directly influence wheezing symptom and asthma attacks in the analyzed group. IgE, eosinophils, and wheezing episodes may be considered key indicators with which to evaluate the adverse effects of PM2.5 air pollution on children's health.

Journal Article

Abstract  IMPORTANCE: The house dust mite (HDM) sublingual allergen immunotherapy (SLIT) tablet is a potential novel treatment option for HDM allergy-related asthma.

OBJECTIVES: To evaluate the efficacy and adverse events of the HDM SLIT tablet vs placebo for asthma exacerbations during an inhaled corticosteroid (ICS) reduction period.

DESIGN, SETTINGS, AND PARTICIPANTS: Double-blind, randomized, placebo-controlled trial conducted between August 2011 and April 2013 in 109 European trial sites. The trial included 834 adults with HDM allergy-related asthma not well controlled by ICS or combination products, and with HDM allergy-related rhinitis. Key exclusion criteria were FEV1 less than 70% of predicted value or hospitalization due to asthma within 3 months before randomization. Efficacy was assessed during the last 6 months of the trial when ICS was reduced by 50% for 3 months and then completely withdrawn for 3 months.

INTERVENTIONS: 1:1:1 randomization to once-daily treatment with placebo (n = 277) or HDM SLIT tablet (dosage groups: 6 SQ-HDM [n = 275] or 12 SQ-HDM [n = 282]) in addition to ICS and the short-acting β2-agonist salbutamol.

MAIN OUTCOMES AND MEASURES: Primary outcome was time to first moderate or severe asthma exacerbation during the ICS reduction period. Secondary outcomes were deterioration in asthma symptoms, change in allergen-specific immunoglobulin G4 (IgG4), change in asthma control or asthma quality-of-life questionnaires, and adverse events.

RESULTS: Among 834 randomized patients (mean age, 33 years [range, 17-83]; women, 48%), 693 completed the study. The 6 SQ-HDM and 12 SQ-HDM doses both significantly reduced the risk of a moderate or severe asthma exacerbation compared with placebo (hazard ratio [HR]: 0.72 [95% CI, 0.52-0.99] for the 6 SQ-HDM group, P = .045, and 0.69 [95% CI, 0.50-0.96] for the 12 SQ-HDM group, P = .03). The absolute risk differences based on the observed data (full analysis set) in the active groups vs the placebo group were 0.09 (95% CI, 0.01-0.15) for the 6 SQ-HDM group and 0.10 (95% CI, 0.02-0.16) for the 12 SQ-HDM group. There was no significant difference between the 2 active groups. Compared with placebo, there was a reduced risk of an exacerbation with deterioration in asthma symptoms (HR, 0.72 [95% CI, 0.49-1.02] for the 6 SQ-HDM group, P = .11, and 0.64 [95% CI, 0.42-0.96] for the 12 SQ-HDM group, P = .03) and a significant increase in allergen-specific IgG4. However, there was no significant difference for change in asthma control questionnaire or asthma quality-of-life questionnaire for either dose. There were no reports of severe systemic allergic reactions. The most frequent adverse events were mild to moderate oral pruritus (13% for the 6 SQ-HDM group, 20% for the 12 SQ-HDM group, and 3% for the placebo group), mouth edema, and throat irritation.

CONCLUSIONS AND RELEVANCE: Among adults with HDM allergy-related asthma not well controlled by ICS, the addition of HDM SLIT to maintenance medications improved time to first moderate or severe asthma exacerbation during ICS reduction, with an estimated absolute reduction at 6 months of 9 to 10 percentage points; the reduction was primarily due to an effect on moderate exacerbations. Treatment-related adverse events were common at both active doses. Further studies are needed to assess long-term efficacy and safety.

TRIAL REGISTRATION: clinicaltrialsregister.eu Identifier: 2010-018621-19.

Journal Article

Abstract  The quality of indoor air is one of the significant elements that influences people's well-being and health inside buildings. Emissions of pollutants, which may cause odor nuisance, are the main reason for people's complaints regarding the quality of indoor air. As a result, it is necessary to perform tests aimed at identifying the sources of odors inside buildings. The article contains basic information on the characteristics of the sources of indoor air pollution and the influence of the odor detection threshold on people's health and comfort. An attempt was also made to classify and use sensory analysis techniques to perform tests of the quality of indoor air, which would enable identification of sensory experience and would allow for indication of the degree of their intensity.

DOI
Journal Article

Abstract  Optical non-intrusive measurements are performed to a 10 kWth laboratory-scale dual swirl pulverized coal combustion burner in order to elucidate the behaviors of internal recirculation zone (IRZ) and heat release region. The pulverized coal flame is operated with four different swirl combinations: co-swirling (low-and high-swirl) and counter-swirling (low-and high-swirl). The flow field is measured using particle image velocimetry (PIV). The IRZ area increases for the high-swirl conditions than that in the low-swirl conditions. With changing from co-to counter-swirl combination, the IRZ appearance changes from a heart-to an elongate-shape IRZ because double stagnation points for the co-swirling flames merges to one stagnation point for the counter-swirling flames. For the co-swirling conditions, a tube-type vortex is detected at the end of the IRZ near the double stagnation points. However, it is not present in the counter-swirling conditions. From two-color pyrometry, the overall temperature in the high-swirl flames is lower than the low-swirl flames. For the counter-swirling flames, higher temperature is observed due to the better mixing, which allows for a more intense combustion reaction of pulverized coal particles. Flame color measurements (OH and CH chemiluminescence band light emission) shows that the devolatilization of coal particles is observed at more upstream region comparing with the heat release reaction for volatile gas combustion. For the high-swirl flames, the CH/band intensity for heat release decreases, however its overall dimension increases. For the counter-swirling flames, the higher heat release is observed. (c) 2016 Published by Elsevier Ltd.

Journal Article

Abstract  PURPOSE: The study was conducted to explore the mechanisms linking traffic-related air pollution and cardio-metabolic risk.

METHODS: The participants included 371 men and women aged from 45 to 75 in an urban residential area in Shanghai, China. The participants were divided into four categories (≤50, 51-100, 101-200 and >200 m) according to the residential distance to major road. Additionally, the personal fine particulate matter (PM2.5) was measured from 8:00 am to 6:00 pm to assess the PM2.5 exposure in general residents. Then, the continuous subclinical measurements and biological effects related to cardio-metabolic disorders were detected. The generalized linear regression analysis was applied for estimating the adjusted hazards ratio for cardio-metabolic disorders relative to traffic-related air pollution.

RESULTS: The average personal PM2.5 is 111.1 μg/m(3) in the participants living within 50 m to major road, which is significantly higher than the personal PM2.5 (68.2 μg/m(3)) in the participants living more than 200 m away from the major road. The participants living within 50 m to major road compared with those living more than 200 m away have 1.15 times higher of heart rate (HR), 1.95 times higher of fasting insulin, 1.30 times higher of homeostasis model assessment of insulin resistance (HOMA-IR), 1.56 times higher of low-density lipoprotein cholesterol (LDL-C), 8.39 times higher of interleukin 6 (IL-6), 4.30 times higher of augmentation index (AI), 1.60 times higher of systolic blood pressure (SBP) and 1.91 times higher of diastolic blood pressure (DBP). Contrary to the increase in above biological effects, there were 1.06 times lower of low frequency (LF), 1.05 times lower of high frequency (HF), 2.54 times lower of IL-10, 4.61 times lower of nitric oxide (NO), 1.19 times lower of superoxide dismutase (SOD) and 1.85 times lower of total antioxidant capacity (T-AOC). There was no clear exposure-response relationship can be observed in the fasting glucose, LF/HF, cholesterol and high-density lipoprotein (HDL).

CONCLUSION: Long-term exposure to traffic-related air pollution may contribute to the development or exacerbation of cardio-metabolic disorders. The mechanisms linking air pollution and cardio-metabolic disorders may be associated with the increased systemic inflammation and oxidative stress, reduced insulin sensitivity and elevated arterial stiffness and blood pressure.

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