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Temporal Variations in Concentrations of Ozone, Nitrogen Dioxide, and Carbon Monoxide at Osijek, Croatia  [PDF]
Elvira Kova?-Andri?,Tatjana Radanovi?,Iva Topalovi?,Berislav Markovi?,Nikola Saka?
Advances in Meteorology , 2013, DOI: 10.1155/2013/469786
Abstract: The purpose of this study was to investigate the ozone, carbon monoxide, and nitrogen dioxide variations and their correlation with meteorological parameters in Osijek (Eastern Croatia) during the summer seasons of 2002, 2007, and 2012. The measured data are discussed in relation to the EU guidelines (Directive 2002/3/EC, Directive 2008/50/EC). In order to characterize ambient air with respect to ozone photochemical pollution we calculated three photochemical pollution indicators. These indicators may also be a valid measure for harmful effects on living organisms. The influence of local meteorological parameters on the measured concentrations of ozone, carbon monoxide, and nitrogen dioxide was also investigated. We have attempted to establish correlations between measured pollutant concentrations and meteorological parameters using the technique of multivariate principal component analysis (PCA). 1. Introduction Air pollution is a common theme for the past decades because of it is growing source of general pollution and the most common source in urban areas being vehicle exhaust. The main pollutants from diesel fuel vehicles include carbon monoxide (CO) and nitrogen dioxide (NO2) from which secondary pollutant ozone (O3) is formed [1]. For a long time, ozone was fairly constant trace constituent of the air, but, in recent years, its concentration in the surface layer of the atmosphere shows a steady increase and at the present time it is greater than ever. Its volume fraction during the preindustrial period increased 2 to 4.5 times and it is still rising [2]. In urban areas or polluted atmosphere various reactions are carried out in which the formation of O3 depends on the ratio of nitrogen oxides ( ), while the effect of CO cycles is such that it slowly oxidizes nitrogen monoxide (NO) to nitrogen dioxide (NO2) and thus indirectly affects the concentration of ozone. Carbon monoxide molecules are entering the cycle of oxidation, and nitrogen monoxide (NO) is oxidized to nitrogen dioxide (NO2). Nitrogen oxides originate mainly from anthropogenic sources, and increased production of ozone in the lower layer is associated with the cycles of photochemical reactions involving volatile organic compounds (VOCs) [3]. Anthropogenic emissions of VOCs and induce changes in the natural sources of tropospheric ozone. If the mixture of and VOCs is irradiated with the visible light, ozone will be generated in the reaction vessel until all the VOCs are spent. The same process is taking place in the air to form large amounts of ozone by solar radiation in the presence
Monitoring Street-Level Spatial-Temporal Variations of Carbon Monoxide in Urban Settings Using a Wireless Sensor Network (WSN) Framework  [PDF]
Tzai-Hung Wen,Joe-Air Jiang,Chih-Hong Sun,Jehn-Yih Juang,Tzu-Shiang Lin
International Journal of Environmental Research and Public Health , 2013, DOI: 10.3390/ijerph10126380
Abstract: Air pollution has become a severe environmental problem due to urbanization and heavy traffic. Monitoring street-level air quality is an important issue, but most official monitoring stations are installed to monitor large-scale air quality conditions, and their limited spatial resolution cannot reflect the detailed variations in air quality that may be induced by traffic jams. By deploying wireless sensors on crossroads and main roads, this study established a pilot framework for a wireless sensor network (WSN)-based real-time monitoring system to understand street-level spatial-temporal changes of carbon monoxide (CO) in urban settings. The system consists of two major components. The first component is the deployment of wireless sensors. We deployed 44 sensor nodes, 40 transmitter nodes and four gateway nodes in this study. Each sensor node includes a signal processing module, a CO sensor and a wireless communication module. In order to capture realistic human exposure to traffic pollutants, all sensors were deployed at a height of 1.5 m on lampposts and traffic signs. The study area covers a total length of 1.5 km of Keelung Road in Taipei City. The other component is a map-based monitoring platform for sensor data visualization and manipulation in time and space. Using intensive real-time street-level monitoring framework, we compared the spatial-temporal patterns of air pollution in different time periods. Our results capture four CO concentration peaks throughout the day at the location, which was located along an arterial and nearby traffic sign. The hourly average could reach 5.3 ppm from 5:00 pm to 7:00 pm due to the traffic congestion. The proposed WSN-based framework captures detailed ground information and potential risk of human exposure to traffic-related air pollution. It also provides street-level insights into real-time monitoring for further early warning of air pollution and urban environmental management.
Does urban asthma exist? How climatic changes and urban air pollution intervene on asthma and respiratory allergy
Isabella Annesi-Maesano
Multidisciplinary Respiratory Medicine , 2011, DOI: 10.1186/2049-6958-6-1-10
Abstract: Several investigations have indicated that individuals living in cities have a higher risk of suffering from asthma and allergies compared to those living in the countryside, this being due to several factors. Besides the fact that individual susceptibility varies between urban and rural settings, there are environmental factors that are typical of living in a city.First of all, as perfectly indicated by D'Amato in his article, urban air pollution is composed of gases and particles. Whereas industrial pollution has decreased in recent decades, at least in industrialized countries, air pollution related to traffic is rising or remaining at the same level http://www.eea.org webcite. Gases and particulate matter have been shown by experimental and epidemiological studies to be involved in respiratory adverse effects. At the population level, not only can short-term exposure to elevated concentrations of urban air pollutants exacerbate pre-existing asthma and allergic rhinitis but also long-term exposure to these pollutants can be responsible for adverse effects, including asthma and the development of allergies [2]. Most investigations reporting long-term effects of air pollution have considered exposure to background air pollution as assessed by monitoring stations, which provide an under-estimation of the real exposure to these pollutants. Fewer studies have considered a more robust assessment of the individual's exposure to air pollution so avoiding miss-classification of exposure. Among them, very recently, is the French 6 Cities study in which long-term average exposure to major urban air pollutants, including benzene, volatile organic compounds (VOCs), sulfur dioxide (SO2), particles with an aerodynamic diameter of 10 μm or less (PM10), nitrogen dioxide (NO2), nitrogen oxides (NOx), and carbon monoxide (CO), was assessed using a dispersion model capable of capturing small-scale variations in 6,683 children. These children underwent clinical examinations, includin
Carbon Monoxide Concentration Monitoring in Akure—A Comparison between Urban and Rural Environment  [PDF]
Ifeoluwa Adebowale Balogun, Ahmed Adedoyin Balogun, Jimmy Adegoke
Journal of Environmental Protection (JEP) , 2014, DOI: 10.4236/jep.2014.54030
Abstract:

Air pollution has been identified to be one major problem associated with urbanisation, particularly in developing countries. In this regard, this paper utilizes data from a year-long experiment of simultaneous measurements to examine and compare the variations of carbon monoxide concentrations, a major air pollutant at urban and rural site in Akure, a medium-sized tropical city in south western Nigeria. The comparison was done to assess the urban influence on the air pollutant. CO concentrations at the urban centre have been identified to exhibit distinct diurnal and day-of-week variations with respect to traffic rush hours. It is also observed that the concentrations at the urban centre were 2 - 3 times higher than that of the rural site which exhibited a consistent cyclic diurnal pattern throughout the week. Results further identified the major cause of CO concentration in the urban centre to be vehicular as consistent increase of the air pollutant from 08:00 to 16:00 during the weekdays is found to be associated with “school runs and rush hours” and also rises through the midnight hours on days linked with social events, particularly Saturdays. In relation to human health and World Health Organisation (WHO) guidelines, results showed that CO concentrations at the urban centre exceeded the WHO 8-hour average recommendation during daytime throughout the weekdays.

Measurements of ozone and its precursors in Beijing during summertime: impact of urban plumes on ozone pollution in downwind rural areas  [PDF]
J. Xu,J. Z. Ma,X. L. Zhang,X. B. Xu
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2011, DOI: 10.5194/acp-11-12241-2011
Abstract: Sea-land and mount-valley circulations are the dominant mesoscale synoptic systems affecting the Beijing area during summertime. Under the influence of these two circulations, the prevailing wind is southwesterly from afternoon to midnight, and then changes to northeasterly till forenoon. In this study, surface ozone (O3), carbon monoxide (CO), nitric oxide (NO), nitrogen dioxide (NO2), nitrogen oxide (NOx) and non-methane hydrocarbons (NMHCs) were measured at four sites located along the route of prevailing wind, including two upwind urban sites (Fengtai "FT" and Baolian "BL"), an upwind suburban site (Shunyi "SY") and a downwind rural site (Shangdianzi "SDZ") during 20 June–16 September 2007. The purpose is to improve our understanding of ozone photochemistry in urban and rural areas of Beijing and the influence of urban plumes on ozone pollution in downwind rural areas. It is found that ozone pollution was synchronism in the urban and rural areas of Beijing, coinciding with the regional-scale synoptic processes. Due to the high traffic density and local emissions, the average levels of reactive gases NOx and NMHCs at the non-rural sites were much higher than those at SDZ. The level of long-lived gas CO at SDZ was comparable to, though slightly lower than, at the urban sites. We estimate the photochemical reactivity (LOH and the ozone formation potential (OFP) in the urban (BL) and rural (SDZ) areas using measured CO and NMHCs. The OH loss rate coefficient (LOH by total NMHCs at the BL and SDZ sites are estimated to be 50.7 s-1 and 15.8 s-1, respectively. While alkenes make a major contribution to the LOH, aromatics dominate OFP at both urban and rural sites. With respect to the individual species, CO has the largest ozone formation potential at the rural site, and at the urban site aromatic species are the leading contributors. While the O3 diurnal variations at the four sites are typical for polluted areas, the ozone peak values are found to lag behind one site after another along the route of prevailing wind from SW to NE. Intersection analyses of trace gases reveal that polluted air masses arriving at SDZ were more aged with both higher O3 and Ox concentrations than those at BL. The results indicate that urban plume can transport not only O3 but its precursors, the latter leading more photochemical O3 production when being mixed with background atmosphere in the downwind rural area.
Air Pollution by Carbon Monoxide (CO) Poisonous Gas in Lagos Area Southwestern Nigeria  [PDF]
Kayode S. John, Kamson Feyisayo
Atmospheric and Climate Sciences (ACS) , 2013, DOI: 10.4236/acs.2013.34053
Abstract:

We examined exposure to air pollution caused by households’ wood burning of cooking, generating sets and vehicle emissions of carbon monoxide (CO) poisonous gas in the most populated urban city of Lagos Southwestern part of Nigeria. It is a known fact that many families including children and pregnant women; infant babies and individuals lost their lives due to poor quality air control policies, and inefficient control of air pollution caused by this deadly gas. Many are suffering with heart-related diseases as a result of CO poisoning and Government is not showing serious concern in this part of the world. All of the foregoing motivates this study to determine the level of human exposure to this deadly gas using Carbon Monoxide Detector so as to create the necessary adequate awareness of the quality of air within the metropolis whereby preventive measures could be put in place to curb the devastating effects on the innocent citizens, most importantly, the children.

Carbon Monoxide Concentration in Different Districts of Tehran
F Changani,Mojgan Baniardalani,K A'azam
Iranian Journal of Pediatrics , 2003,
Abstract: Air pollution is a major problem in Tehran. Most important agents responsible for the high pollution include carbon monoxide, sulfur dioxide, nitrogen dioxide, hydrocarbons and suspended particles. Determination of quality and quantity of polluting agents is of great importance for sustaining the inhabitants health level. We studied carbon monoxide, one of the most hazardous air-polluting agents, in 22 urban districts of Tehran. The results showed that in average 4.39% of the air in Tehran has a CO concentration of 15-30 ppm. The 12th district with 17.99% and 11th district with 16.43% had the highest pollution of carbon monoxide. 6th and 7th districts had 11.22% and 9.5% respectively. The lowest level of pollution was found in 21st district (0%) and 1st district (0.11%). Variance analysis of districts of Tehran showed that there is a significant relation between mean air pollution of 11th and 12th districts and other districts.
Sources of Air Pollution and Strategies for Its Management in The Nigerian Urban Cities
Bolaji, B.O.
The Social Sciences , 2013,
Abstract: This study examines sources of air pollution and strategies for its management in the urban cities. Emphasis is laid on industrial air pollution and vehicular emission, which are the major urban air polluters. Various gases that are emitted by industries into the atmosphere near and around dwelling places were analyzed. Also analyzed is the combustion of large quantity of transportation fuels in the urban cities, which releases several contaminants into the atmosphere. These contaminants include carbon monoxide, hydrocarbons, oxides of nitrogen, lead and other particulate matter. Various strategies which can be employed for the management of urban air pollution are discussed, covering stack monitoring, changing process operation and cleaning flue gases for industrial emissions and changing fuel type, removing gross polluters, cleaning vehicle exhaust gases and traffic management for vehicular emissions.
INDOOR AIR POLLUTION
Ahmet Soysal,Yucel Demiral
TAF Preventive Medicine Bulletin , 2007,
Abstract: The existance of hazardious materials including biological, chemical, and physical agents such as carbon dioxide, carbon monoxide, sulphur dioxide, nitrogen oxides, radon, volotile organic compounds, microorganisms in houses and the other non-industrilized buildings have been defined as indoor air pollution . Indoor air pollutants could possible arised from inside or outside environment and categorized into six subgroups. Almost 80% Turkish population have living in the urban areas and people in the cities have spending approximetely 90% of their time in the closed enviroments, health problems could increased due to indoor air pollution. Moreover, currently there is no specific regulation on this area. [TAF Prev Med Bull. 2007; 6(3): 221-226]
Health Effects of Climate and Air Pollution in Buenos Aires: A First Time Series Analysis  [PDF]
Rosana Abrutzky, Laura Dawidowski, Patricia Matus, Patricia Romero Lankao
Journal of Environmental Protection (JEP) , 2012, DOI: 10.4236/jep.2012.33033
Abstract: Background: The impact of urban air pollution and temperature changes over health is a growing concern for epidemiologists all over the world and particularly for developing countries where fewer studies have been performed. Aim: The main goal of this paper is to analyze the short term effects of changes in temperature and atmospheric carbon monoxide on daily mortality in Buenos Aires, Argentina. Methods: We conducted a time series study focused on three age groups, gender, and cardiovascular and respiratory mortality, with lags up to four days and temporal variables as modifiers. Results: Temperature correlates positively with total mortality for summer months, with a RR = 1.0184 (95%, CI 1.0139, 1.0229) on the same day for each 1℃ increase. In winter this relationship reverses, as 1?C temperature increase exhibit a protective effect with a RR = 0.9894 (95%, CI 0.9864, 0.9924) at the 3 day lag. Carbon monoxide correlates always positively with mortality, with a RR = 1.0369 (95%, CI 1.0206, 1.0534) for each 1 ppm increase, on the previous day. Conclusions: Climate and pollution parameters measured in Buenos Aires City exhibit a correlation with health outcomes. The impacts of temperature and carbon monoxide vary with age and gender, being elderly the most susceptible subgroup. One day after an increase in CO of 1 ppm, about 4% extra deaths can be expected. The correlation found between increases in CO and mortality for greater lags may be ascribed to the role of CO as a chemical marker of urban air pollution, indicating the co-presence of other pollutants.
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