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Spatiotemporal Analysis of Carbon Monoxide Observed by Terra/MOPITT in the Troposphere of Iran
2020
Raispour, K. | Khosravi, Y.
It has been more than 20 years that the Measurement of Pollution in The Troposphere (MOPITT) mission onboard the NASA Terra satellite keeps providing us CO atmospheric concentration measurements around the globe. The current paper observes CO mixing ratio from the MOPITT Version 8 (MOP03J_V008) instrument in order to study the spatiotemporal analysis of CO (spanning from April 2000 to February 2020) in the Troposphere of Iran. Results indicate that the average CO in Iran’s troposphere has been 133.5 ppbv (i.e., 5.5 ppbv lower than the global mean CO). The highest distribution of CO (with an average of 150 ppbv) belongs to the city of Tehran (the capital of Iran) as well as the Caspian Sea coastal area, while the lowest value (with an average of less than 110 ppbv) has been estimated on the Zagros Mountains (southwestern Iran). The highest and lowest CO values have been observed in cold and hot months, respectively. Seasonally speaking, it is also clear that the highest and lowest carbon monoxide values occur in winter and summer, respectively. The vertical profile of MOPITT CO shows the maximum CO concentration at lower levels of the troposphere. It has been expanded up to 150 hPa. The trend is investigated by means of Pearson correlation coefficient statistical method. Overall, long-term monitoring of MOPITT CO in Iran indicates a decreasing trend of tropospheric CO over the 20 years (Y=-0.008X+449.31). Possible reasons for such a decrease can be related to improved transportation fleet, increased fuel quality, plans for traffic control, promotion of heating systems, and promotion of industrial fuels and factories.
Показать больше [+] Меньше [-]Air Pollution in the Capital City of Bangladesh: Its Causes and Impacts on Human Health
2020
Khuda, K. E.
Air is one of the precious natural resources that are essential for animal including the human being. It is also the most important gift of nature without which human cannot survive. Pollution in the urban areas like Cairo, Delhi, Mexico and Dhaka far surpasses the acceptable limits set by the World Health Organization (WHO). Urban air pollution in the South Asian region is approximated to cause more than 300,000 deaths and billions of cases of respiratory disease per year. In Bangladesh, about 200000 people die each year due to the air pollution as the WHO estimates in 2018. The air in Dhaka City, the capital of Bangladesh, has become worsen to a level that the city has been identified as one of the most polluted cities in the world. Taking the problem with utmost importance into consideration as it is related with the public health, air pollution is being treated as one of the priority issues. The level of pollution at roadside environment is deeply connected with the density of motor vehicles plying on the roads. This situation is expected to worsen further in the upcoming days due to the increasing number of motor vehicles resulted from rapid economic growth and industrialization. This paper aims to provide the present statues of the air pollution in Dhaka city and some specific recommendations for making the city as a better living place through reducing its air pollution.
Показать больше [+] Меньше [-]Assessing Indoor Air Pollution within Different Areas of Female Beauty Centers and Exploring Their Relation to Various Respiratory Symptoms
2016
Almarshad, Saja
The staff working at beauty centers are exposed to various chemicalproducts used daily in their working environment. Both hair dressers and nail techniciansare exposed to chemicals that are known to have an influence on the respiratory system.In order to evaluate such influence, this cross-sectional observational study wasconducted on a randomly selected 14 beauty centers in Dammam City, Saudi Arabia. Atthe investigated salons, both of respiratory symptoms and the quality of air wereevaluated and data were analyzed statistically. 40.5% out of the 79 subjects included inthe study were hairdressers, 17.7% were nail technicians and (41.8%) were working inboth of the previously mentioned areas as part of their everyday practice. The staffcomplained of respiratory symptoms which include dyspnea, cough, phlegm, wheeze, andshortness of breath. Both hairdressers and nail technicians developed respiratorysymptoms while working in the salons. Indoor Air pollution was assessed and many datawere out of the normal standard ranges which include: relative humidity (RH), volatileorganic compounds (VOC), carbon dioxide (CO2), and ammonia (NH3). We conclude thatgood ventilation is required to reduce the influence of such substances on the respiratorysymptoms of the staff working at salons.
Показать больше [+] Меньше [-]Modeling Airflow in Urban High-Rise Building Areas and Climate Comfort
2024
Zahedifar, Tahmineh | Darabi, Hassan
Urban morphology impacts micro-climates, solar energy absorption, air flow, wind patterns, energy consumption, and air pollution concentration. Temperature control in public spaces reduces heat island formation, while ventilation corridors potentially improve air quality. However, despite the literature on airflow and urban tall buildings providing valuable insights, further research is needed to understand the complex relationship between airflow patterns and urban high-rise buildings. This research should consider factors such as landscape types, building height, density, and orientation. This research aims to examine airflow patterns in high-rise buildings that are influenced by nearby land use, which can impact ventilation and climate comfort. To investigate these objectives, we utilized the Universal Thermal Climate Index (UTCI) and Predicted Mean Vote Index (PMV) by conducting simulations using ENVI-met software. The results revealed that buildings with narrower widths have better wind warded front conditions, while those with an unfavorable wind angle or a narrow facade are less comfortable. Public spaces that face the wind benefit from improved ventilation. It is essential to consider the optimal arrangement, ventilation, and height of buildings to ensure the favorable airflow. Factors such as the placement of trees, the use of porous walls, water features such as fountains and sprinklers, and the local climate all contribute to creating better wind conditions. Investigating the reciprocal interaction between the landscape, high-rise buildings, and climate comfort could be considered in future research.
Показать больше [+] Меньше [-]Characteristics and Health Risk of BTEX at Selected Different Microenvironments in an Industrial-Urban Area, Iran
2019
Tarassoli, A. | Esmaili Sari, A. | Bahramifar, N.
The present study monitors BTEX concentration in outdoor and indoor air of eight different microenvironments during summer 2017 and winter 2018 at Asaloyeh city, Iran's energy capital. It samples BTEX compounds by charcoal tubes, analyzing the samples by means of a gas chromatograph with a flame ionization detector. According to the obtained results, outdoor concentrations of BTEX have been higher than the indoor ones, for both seasons, with the highest outdoor and indoor BTEX being 21.70 and 18.59 μg/m3, respectively. Toluene has been the most abundant substance, among the investigated BTEX in all sampling points. Based on the MIR scale, m, p-xylene is the most dominant contributor to ozone formation potential among BTEX species. Indoor to outdoor (I/O) ratios of BTEX compounds range from 0.53 to 0.88 and 0.41 to 0.77 in winter and summer, respectively. The cumulative hazard index (HI) is within an acceptable range. The LTCR value of benzene concentration, obtained, exceeds the value of 1.0E-06, recommended by USEPA. Sensitivity analysis shows that benzene concentration, exposure duration, and inhalation rate have a greater impact on health risk assessment.
Показать больше [+] Меньше [-]Wood burning impact on the ambient air quality of four French cities : Evaluation of the approach by organic tracers | Impact de la combustion du bois sur la qualité de l'air ambiant de quatre villes de France : évaluation de l'approche par traceurs organiques
2009
Pissot, Nicolas | Besombes, Jean-Luc | Leoz-Garziandia, Eva | Jaffrezo, Jean-Luc
Nowadays, promoted as a renewable energy, biomass burning becomes more and more widespread all over the world. In urban and rural areas biomass, mainly wood, is burned for heating, cooking, and waste disposal purposes. This biofuel seems to be an alternative to the rarefaction of the fossil fuel and, moreover it decreases the emission of carbon dioxide causing global warming. However, wood smoke contains various air pollutants such as fine particulate matter (PM10, PM2.5), polycyclic aromatic hydrocarbons (PAHs), benzene, dioxins... and in consequence has an impact on the air quality. In order to estimate the contribution of wood burning on the atmospheric organic aerosol of urban areas, the French ministry of environment (MEEDDAT), called upon this study during the winter 2006/2007, in the French cities of Grenoble, Lille, Strasbourg and Gennevilliers. For this work, different species have been looked after. The global characterization of the atmospheric aerosols has been made taking in account the PM10, the organic carbon (OC), and the elementary carbon (EC). Measurement of biomass burning tracers (levoglucosan, mannosan, and galactosan) has been undertaken, as well as methoxyphenols, which are more specific wood smoke tracers. The analyses of organic tracers by gas chromatography coupled with a mass spectrometer detector (GC/MS) show average concentrations of levoglucosan in the range of 272 ng.m-3 for Gennevilliers to 1 148 ng.m-3 for Grenoble. Mannosan and galactosan have also been measured in all cities but in lower quantities. The methoxyphenols have been detected only in rare occasions and at the limit of detection of the analytical method. PM10 measurements range from 20.6 micro g.m-3 for Gennevilliers to 35.8 micro g.m-3 for Grenoble. At the same time, OC values range from 3.61 micro g.m-3 to 11.15 micro g.m-3. Moreover high correlations have been observed between levoglucosan and OC, respectively 0.80 and 0.86 for Grenoble and Strasbourg. In addition, with respectively 10.98 ng.m-3 and 8.20 ng.m-3, Grenoble and Strasbourg present the highest particulate PAHs average concentrations of the four cities. All these results seem to indicate that Grenoble and Strasbourg are more impacted by the biomass burning than the two other cities. And more particularly in Grenoble where the organic aerosol fraction is very huge, this last phenomenon is typically characteristic of the biomass burning. To conclude, this study shows and confirms the usefulness of levoglucosan as biomass burning tracer and the difficulty to use methoxyphenols as woodsmoke tracers in ambient areas. | De nos jours, l'utilisation du bois en tant que combustible est relativement répandue en France et dans le monde entier. L'augmentation du prix du pétrole et des autres sources d'énergie épuisables va certainement engendrer dans les années à venir une contribution accrue du chauffage domestique au bois. L'utilisation de cette source d'énergie renouvelable pose cependant de nombreux problèmes sur la santé humaine. En effet, la fumée émise lors de la combustion du bois contient un certain nombre de composés polluants, tels que les hydrocarbures aromatiques polycycliques (HAP), le benzène, les fines particules (PM10, PM2,5)... Les émissions de la combustion du bois ont donc un impact sur la qualité de l'air. Cet impact peut être évalué par l'étude de traceurs organiques spécifiques de la combustion du bois identifiables au sein de la composante organique des aérosols. Ces traceurs sont des produits provenant de la combustion de la cellulose et de l'hémicellulose tels que le lévoglucosan, mannosan, galactosan et des composés issus de la thermodégradation de la lignine tels que les méthoxyphénols. Cette méthode a été appliquée à une étude commanditée à l'INERIS par le ministère de l'Écologie, de l'Énergie, du Développement Durable et de l'Aménagement du Territoire (MEEDDAT), en partenariat avec des Associations agréées de la surveillance de la qualité de l'air (AASQA). L'objectif était de caractériser l'influence de la combustion du bois sur la composante organique de l'aérosol atmosphérique en site urbain. Des prélèvements d'aérosols ont été effectués sur une période allant de novembre 2006 à avril 2007, dans quatre grandes villes de France : Grenoble, Lille, Strasbourg, et Gennevilliers. L'analyse par chromatographie gazeuse couplée à un spectromètre de masse (GC/MS) des traceurs organiques les plus stables, lévoglucosan, mannosan et galactosan, confirme l'influence de cette source sur la qualité de l'air des quatre villes. Sur la période d'étude, la concentration moyenne en lévoglucosan varie de 272 ng.m-3 pour la ville de Gennevilliers à 1 148 ng.m-3 pour la ville de Grenoble. La confrontation des résultats de ces traceurs avec les données usuelles de caractérisation de l'aérosol, telles que le carbone organique (OC) et le carbone élémentaire (EC), montre une participation du chauffage au bois plus importante dans les villes de Grenoble et de Strasbourg. Les résultats d'analyse du lévoglucosan obtenus sur la ville de Gennevilliers indiquent une très bonne corrélation avec les HAP particulaires et les PM10. Ces résultats prouvent que la combustion du bois joue un rôle important sur la composition de la matière organique de l'aérosol atmosphérique et sur la pollution particulaire en milieu urbain. En revanche, les méthoxyphénols ont été peu détectés sur les divers échantillons analysés.
Показать больше [+] Меньше [-]Wood burning impact on the ambient air quality of four French cities : Evaluation of the approach by organic tracers | Impact de la combustion du bois sur la qualité de l'air ambiant de quatre villes de France : évaluation de l'approche par traceurs organiques
2009
Pissot, Nicolas | Besombes, Jean-Luc | Leoz-Garziandia, Eva | Jaffrezo, Jean-Luc | Laboratoire de Chimie Moléculaire et Environnement (LCME) ; Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]) | Institut National de l'Environnement Industriel et des Risques (INERIS) | Laboratoire de glaciologie et géophysique de l'environnement (LGGE) ; Observatoire des Sciences de l'Univers de Grenoble (OSUG) ; Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
National audience | Nowadays, promoted as a renewable energy, biomass burning becomes more and more widespread all over the world. In urban and rural areas biomass, mainly wood, is burned for heating, cooking, and waste disposal purposes. This biofuel seems to be an alternative to the rarefaction of the fossil fuel and, moreover it decreases the emission of carbon dioxide causing global warming. However, wood smoke contains various air pollutants such as fine particulate matter (PM10, PM2.5), polycyclic aromatic hydrocarbons (PAHs), benzene, dioxins... and in consequence has an impact on the air quality. In order to estimate the contribution of wood burning on the atmospheric organic aerosol of urban areas, the French ministry of environment (MEEDDAT), called upon this study during the winter 2006/2007, in the French cities of Grenoble, Lille, Strasbourg and Gennevilliers. For this work, different species have been looked after. The global characterization of the atmospheric aerosols has been made taking in account the PM10, the organic carbon (OC), and the elementary carbon (EC). Measurement of biomass burning tracers (levoglucosan, mannosan, and galactosan) has been undertaken, as well as methoxyphenols, which are more specific wood smoke tracers. The analyses of organic tracers by gas chromatography coupled with a mass spectrometer detector (GC/MS) show average concentrations of levoglucosan in the range of 272 ng.m-3 for Gennevilliers to 1 148 ng.m-3 for Grenoble. Mannosan and galactosan have also been measured in all cities but in lower quantities. The methoxyphenols have been detected only in rare occasions and at the limit of detection of the analytical method. PM10 measurements range from 20.6 micro g.m-3 for Gennevilliers to 35.8 micro g.m-3 for Grenoble. At the same time, OC values range from 3.61 micro g.m-3 to 11.15 micro g.m-3. Moreover high correlations have been observed between levoglucosan and OC, respectively 0.80 and 0.86 for Grenoble and Strasbourg. In addition, with respectively 10.98 ng.m-3 and 8.20 ng.m-3, Grenoble and Strasbourg present the highest particulate PAHs average concentrations of the four cities. All these results seem to indicate that Grenoble and Strasbourg are more impacted by the biomass burning than the two other cities. And more particularly in Grenoble where the organic aerosol fraction is very huge, this last phenomenon is typically characteristic of the biomass burning. To conclude, this study shows and confirms the usefulness of levoglucosan as biomass burning tracer and the difficulty to use methoxyphenols as woodsmoke tracers in ambient areas. | De nos jours, l'utilisation du bois en tant que combustible est relativement répandue en France et dans le monde entier. L'augmentation du prix du pétrole et des autres sources d'énergie épuisables va certainement engendrer dans les années à venir une contribution accrue du chauffage domestique au bois. L'utilisation de cette source d'énergie renouvelable pose cependant de nombreux problèmes sur la santé humaine. En effet, la fumée émise lors de la combustion du bois contient un certain nombre de composés polluants, tels que les hydrocarbures aromatiques polycycliques (HAP), le benzène, les fines particules (PM10, PM2,5)... Les émissions de la combustion du bois ont donc un impact sur la qualité de l'air. Cet impact peut être évalué par l'étude de traceurs organiques spécifiques de la combustion du bois identifiables au sein de la composante organique des aérosols. Ces traceurs sont des produits provenant de la combustion de la cellulose et de l'hémicellulose tels que le lévoglucosan, mannosan, galactosan et des composés issus de la thermodégradation de la lignine tels que les méthoxyphénols. Cette méthode a été appliquée à une étude commanditée à l'INERIS par le ministère de l'Écologie, de l'Énergie, du Développement Durable et de l'Aménagement du Territoire (MEEDDAT), en partenariat avec des Associations agréées de la surveillance de la qualité de l'air (AASQA). L'objectif était de caractériser l'influence de la combustion du bois sur la composante organique de l'aérosol atmosphérique en site urbain. Des prélèvements d'aérosols ont été effectués sur une période allant de novembre 2006 à avril 2007, dans quatre grandes villes de France : Grenoble, Lille, Strasbourg, et Gennevilliers. L'analyse par chromatographie gazeuse couplée à un spectromètre de masse (GC/MS) des traceurs organiques les plus stables, lévoglucosan, mannosan et galactosan, confirme l'influence de cette source sur la qualité de l'air des quatre villes. Sur la période d'étude, la concentration moyenne en lévoglucosan varie de 272 ng.m-3 pour la ville de Gennevilliers à 1 148 ng.m-3 pour la ville de Grenoble. La confrontation des résultats de ces traceurs avec les données usuelles de caractérisation de l'aérosol, telles que le carbone organique (OC) et le carbone élémentaire (EC), montre une participation du chauffage au bois plus importante dans les villes de Grenoble et de Strasbourg. Les résultats d'analyse du lévoglucosan obtenus sur la ville de Gennevilliers indiquent une très bonne corrélation avec les HAP particulaires et les PM10. Ces résultats prouvent que la combustion du bois joue un rôle important sur la composition de la matière organique de l'aérosol atmosphérique et sur la pollution particulaire en milieu urbain. En revanche, les méthoxyphénols ont été peu détectés sur les divers échantillons analysés.
Показать больше [+] Меньше [-]Microplastic appraisal of soil, water, ditch sediment and airborne dust: The case of agricultural systems
2023
Lwanga, Esperanza Huerta | Van Roshum, Ilse | Munhoz, Davi | Meng, Ke | Rezaei, Mahrooz | Goossens, Dirk | Bijsterbosch, Judith | Alexandre, Nuno | Oosterwijk, Julia | Krol, Maarten | Peters, Piet | Geissen, Violette | Ritsema, Coen
Although microplastic pollution jeopardizes both terrestrial and aquatic ecosystems, the movement of plastic particles through terrestrial environments is still poorly understood. Agricultural soils exposed to different managements are important sites of storage and dispersal of microplastics. This study aimed to identify the abundance, distribution, and type of microplastics present in agricultural soils, water, airborne dust, and ditch sediments. Soil health was also assessed using soil macroinvertebrate abundance and diversity. Sixteen fields were evaluated, 6 of which had been exposed to more than 5 years of compost application, 5 were exposed to at least 5 years of plastic mulch use, and 5 were not exposed to any specific management (controls) within the last 5 years. We also evaluated the spread of microplastics from the farms into nearby water bodies and airborne dust. We found 11 types of microplastics in soil, among which Light Density Polyethylene (LDPE) and Light Density Polyethylene covered with pro-oxidant additives (PAC) were the most abundant. The highest concentrations of plastics were found in soils exposed to plastic mulch management (128.7 ± 320 MPs.g-1 soil and 224.84 ± 488 MPs.g-1 soil, respectively) and the particles measured from 50 to 150 μm. Nine types of microplastics were found in water, with the highest concentrations observed in systems exposed to compost. Farms applying compost had higher LDPE and PAC concentrations in ditch sediments as compared to control and mulch systems; a significant correlation between soil polypropylene (PP) microplastics with ditch sediment microplastics (r2 0.7 p 0.05) was found. LDPE, PAC, PE (Polyethylene), and PP were the most abundant microplastics in airborne dust. Soil invertebrates were scarce in the systems using plastic mulch. A cocktail of microplastics was found in all assessed matrices.
Показать больше [+] Меньше [-]Exposure of construction workers to hazardous emissions in highway rehabilitation projects measured with low-cost sensors
2022
Blaauw, Sheldon A. | Maina, James W. | O'Connell, Johan
Construction workers on highway rehabilitation projects can be exposed to a combination of traffic- and construction-related emissions. To assess the personal exposure a worker experiences, a portable battery-operated Air Quality Device (AQD) was utilised to measure emissions during normal construction operations of a major road rehabilitation project. Emissions measured were nitrogen dioxide (NO₂), Total Volatile Organic Compounds (TVOCs) and Particulate Matter (PM₁₀, PM₂.₅, and PM₁). The objective of the paper is to document the hazardous emissions that construction workers may be exposed to and allow for a basis of informed decision making to mitigate the risks of a road construction project. Most critically, this article is designed to raise awareness of the potential impact to a worker's wellbeing as well as highlight the need for further research. Through statistical analysis, asphalt paving was identified as the most hazardous activity in terms of exposure relative to other activities. This activity was further assessed using discrete-time Markov chain Monte Carlo simulations with results indicating a high probability that workers may be exposed to greater hazardous emission concentrations than measured. Limiting the distance to the source of emissions, large-scale use of warm-mix asphalt and reducing the idling times of construction vehicles were identified as practical mitigation measures to reduce exposure and aid in achieving zero-harm objectives. Finally, it is found that males are more susceptible to long-term implications of hazardous emission inhalation and should be more aware if the scenarios they might work in expose them to this.
Показать больше [+] Меньше [-]Source analysis of the tropospheric NO2 based on MAX-DOAS measurements in northeastern China
2022
Liu, Feng | Xing, Chengzhi | Su, Pinjie | Luo, Yifu | Zhao, Ting | Xue, Jiexiao | Zhang, Guohui | Qin, Sida | Song, Youtao | Bu, Naishun
Ground-based Multi-Axis Differential Optical Absorption Spectroscopy (Max-DOAS) measurements of nitrogen dioxide (NO₂) were continuously obtained from January to November 2019 in northeastern China (NEC). Seasonal variations in the mean NO₂ vertical column densities (VCDs) were apparent, with a maximum of 2.9 × 10¹⁶ molecules cm⁻² in the winter due to enhanced NO₂ emissions from coal-fired winter heating, a longer photochemical lifetime and atmospheric transport. Daily maximum and minimum NO₂ VCDs were observed, independent of the season, at around 11:00 and 13:00 local time, respectively, and the most obvious increases and decreases occurred in the winter and autumn, respectively. The mean diurnal NO₂ VCDs at 11:00 increased to at 08:00 by 1.6, 5.8, and 6.7 × 10¹⁵ molecules cm⁻² in the summer, autumn and winter, respectively, due to increased NO₂ emissions, and then decreased by 2.8, 4.2, and 5.1 × 10¹⁵ molecules cm⁻² at 13:00 in the spring, summer, and autumn, respectively. This was due to strong solar radiation and increased planetary boundary layer height. There was no obvious weekend effect, and the NO₂ VCDs only decreased by about 10% on the weekends. We evaluated the contributions of emissions and transport in the different seasons to the NO₂ VCDs using a generalized additive model, where the contributions of local emissions to the total in the spring, summer, autumn, and winter were 89 ± 12%, 92 ± 11%, 86 ± 12%, and 72 ± 16%, respectively. The contribution of regional transport reached 26% in the winter, and this high contribution value was mainly correlated with the northeast wind, which was due to the transport channel of air pollutants along the Changbai Mountains in NEC. The NO₂/SO₂ ratio was used to identify NO₂ from industrial sources and vehicle exhaust. The contribution of industrial NO₂ VCD sources was >66.3 ± 16% in Shenyang due to the large amount of coal combustion from heavy industrial activity, which emitted large amounts of NO₂. Our results suggest that air quality management in Shenyang should consider reductions in local NO₂ emissions from industrial sources along with regional cooperative control.
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