Air Pollution In Tehran Research Articles

Parametric Evaluation of Indoor Particulate Matters in Elementary Schools in the Central Parts of Tehran

The objective of this work was to evaluate the indoor-outdoor particle size distribution in elementary schools located in central parts of Tehran and to evaluate those parameters that could be influencing the indoor particles concentrations in the classrooms. Concentrations of particles including PM10, PM2.5 and PM1.0, as some of the main air pollutants in Tehran, were measured in the schools, during winter 2009. It was found that the average indoor concentrations of PM10, PM2.5 and PM1.0 were 274 µg/m3, 42 µg/m3 and 19 µg/m3, respectively, while the outdoor concentrations for these particles were 140 µg/m3, 38 µg/m3 and 22 µg/m3, respectively. The main factors influencing indoor particle pollution were found to be the outdoor concentrations of the particles and the physical activity of the students, but other factors such as the differences between indoor and outdoor temperatures, class size dimensions and types of boards in the classrooms had negligible effects.

Interval type-2 fuzzy expert system for prediction of carbon monoxide concentration in mega-cities

This paper presents an indirect approach to interval type-2 fuzzy logic system modeling to forecaste the level of air pollutants. The type-2 fuzzy logic system permits us to model the uncertainties among rules and the parameters related to data analysis. In this paper, we propose an indirect method to create an interval type-2 fuzzy logic system from a historical data, where Footprint of Uncertainties of fuzzy sets are extracted by implementation of an interval type-2 FCM algorithm and based on an upper and lower value for the level of fuzziness m in FCM. Finally, the proposed model is applied for prediction of carbon monoxide concentration in Tehran air pollution. It is shown that the proposed type-2 fuzzy logic system is superior in comparison to type-1 fuzzy logic systems in terms of two performance indices.

Comparison of heart rate variability and cardiac arrhythmias in polluted and clean air episodes in healthy individuals

Pathophysiological mechanisms and pathways linking cardiovascular mortality and morbidity with air pollution were recently hypothesized. The present study evaluated association between air pollution and changes in heart rate variability as a marker of cardiac autonomic function in healthy individuals, and also determined the frequency of cardiac arrhythmias and QT interval changes on polluted compared to unpolluted days. Continuous Holter electrocardiography (ECG) monitoring was conducted on 21 young healthy individuals in the two episodes of clean air and elevated air pollution in Tehran. All subjects underwent a medical history review, a physical examination and echocardiography in order to rule out structural heart diseases. Measured pollutants and parameters included NO(2), CO(2), O(3), SO(2), and PM10, which all showed significantly higher concentrations on polluted days. Holter parameters were measured for 24-h time segments and compared. Maximum heart rate was significantly lower in polluted air conditions in comparison with clean air conditions (115.1±32.2 vs. 128.9±17.7), and the square root of the mean of squared differences between adjacent NN intervals (r-MSSD) was higher in polluted air compared to clean air (99.0±58.2 vs. 58.5±26.4). Also, the occurrence of nonsustained supraventricular tachycardia was reported in 42.9% of participants in air pollution episodes, whereas this arrhythmia was not seen in clear air conditions (p=0.001). Changes in air pollution indices may lead to the occurrence of nonsustained supraventricular tachycardia, a slight reduction in maximum heart rate, and an increase in r-MSSD in healthy individuals. Air quality monitoring in cities associated with a high exposure to air pollutants is recommended in order to prevent such events.

Spatial analysis of auto-multivariate lattice data

Most problems related to environmental studies are innately multivariate. In fact, in each spatial location more than one variable is usually measured. In geostatistics multivariate data analysis, where we intend to predict the value of a random vector in a new site, which has no data, cokriging method is used as the best linear unbiased prediction. In lattice data analysis, where almost exclusively the probability modeling of data is of concern, only auto-Gaussian model has been used for continuous multivariate data. For discrete multivariate data little work has been carried out. In this paper, an auto-multinomial model is suggested for analyzing multivariate lattice discrete data. The proposed method is illustrated by a real example of air pollution in Tehran, Iran.

A Dynamic Model of Air Pollution, Health,and Population Growth Using System Dynamics: A Study on Tehran-Iran (With Computer Simulation by the Software Vensim)

The significance of environmental protection is well- known in today's world. The execution of any program depends on sufficient knowledge and required familiarity with environment and its pollutants. Taking advantage of a systematic method, as a new science, in environmental planning can solve many problems. In this article, air pollution in Tehran and its relationship with health and population growth have been analyzed using dynamic systems. Firstly, by using casual loops, the relationship between the parameters effective on air pollution in Tehran were taken into consideration, then these casual loops were turned into flow diagrams (6), and finally, they were simulated using the software Vensim (16)in order to conclude what the effect of each parameter will be on air pollution in Tehran in the next 10 years, how changing of one or more parameters influences other parameters, and which parameter among all other parameters requires to be controlled more. Keywords—Air pollutions, Simulation, System Dynamics, Tehran, Vensim.

Seasonal variation in ambient PM mass and number concentrations (case study: Tehran, Iran)

Tehran, the capital city of Iran, is an important industrial and commercial center. This city is one of the worst cities in the world in terms of air pollution, which is mostly due to mobile sources rather than stationary sources. Particulate matter (PM), which is a complex mixture of extremely small particles and liquid droplets, is considered as an important source of air pollution in Tehran. In this study, our objective was to study PM(10), PM(2.5), and PM(1.0) mass and number concentrations and find the correlations of these two parameters in the west-central parts of Tehran during two consecutive warm and cold seasons. The particles collected from five stations were analyzed for their mass and number simultaneously by a laser-based Grimm dust monitor. In general, it was found that the accumulation of the PM in this region is more in the cold season. PM(10) mass concentration increases almost twofold and PM(2.5) and PM(1.0) almost three times in this season. The mean number concentration of the particles (0.3-20 microm) was found to be almost 4.8 times in the cold season. It was also noticed that the average dimensions of the particles decrease in that season.

FP06-MO-05 Stroke admission and air pollution in Tehran: a cross sectional study

FP06-MO-05 Stroke admission and air pollution in Tehran: a cross sectional study

Evaluation and Application of the Gaussian-Log Gaussian Spatial Model for Robust Bayesian Prediction of Tehran Air Pollution Data

Evaluation and Application of the Gaussian-Log Gaussian Spatial Model for Robust Bayesian Prediction of Tehran Air Pollution Data

The deterioration of urban environments in developing countries: Mitigating the air pollution crisis in Tehran, Iran

An increasing concentration of people and economic activities as well as a growing vehicle fleet have contributed to high levels of air pollution in the large cities of developing countries. This paper uses the case study of Tehran, the capital of Iran, to address the problem of air pollution in the major cities of developing countries. Specifically, the paper reviews and evaluates the implementation of the 10-year master plan to control air pollution in Tehran since its introduction in 2000. The paper argues that, thus far, the full implementation of many of the strategies of the master plan has lagged behind and a gap has emerged between the plan and its practice. Looking into the future, the paper identifies a list of challenges that need to be addressed systematically and comprehensively in order to turn the master plan and its strategies into meaningful and coordinated practice. Lessons learned from the case study of Tehran will help other major cities in developing countries to combat the air pollution problem more effectively in the future.

Application of satellite data and GIS in studying air pollutants in Tehran

Tehran, capital of Iran, is one of the polluted cities in the region. Due to its geographical location, the ensnared condition as surrounded by mountain ranges, and also lack of perennial winds, the smoke and other particulate matters produced from daily life do not go far in the air. Therefore, usually there is a thick layer of aerosols and other particulate matters in the nearby atmosphere. Air pollution and its health consequences has been a major concern for both citizens and urban planners and decision makers of this city. With regard to this fact, our goal in this study is to examine the application of satellite data and spatial analysis to monitor and map air pollution. We have used satellite data and spatial modeling with the help of GIS to study concentrations of different pollutants in the city. Beside its widespread coverage, satellite data are considerably cost effective relative to traditional air pollution data collection methods. We used moderate resolution imaging spectro-radiometer (MODIS) data, together with ground station data to monitor and map air pollutants. Ground pollution survey stations collect daily amounts of pollutants in different parts of the city. However, these ground stations do not have equal distribution across the city and are not sufficient to get a complete figure of sophisticated patterns of pollution in the area. We extracted maps of particulate matters and aerosols from MODIS image, displaying pollution collectively. With the help of GIS, the data of ground stations used to produce maps of amounts of each pollutant separately. Quantitative MODIS aerosol optical thickness (AOT) data compared with these data using a spatial grid.

The Contribution of Gasoline to Indoor Air Pollution in Tehran, Iran

Volatile organic compounds (VOCs) are released continuously into the indoor environment from a number of sources including building materials, furnishings and household products like air fresheners. In addition there are many activities carried out in houses that release VOCs intermittently. However, a major contributor to indoor pollution, particularly in large cities, is the outdoor environment largely through the concentration of vehicular traffic. In the present study, conducted in Tehran, the group of gasoline components commonly known as BTEX were measured as a surrogate for this pollution under different conditions in the indoor environment. Using a method published by NIOSH, organic vapours were collected by drawing air through charcoal-filled tubes with a portable pump with a flow rate of 0.2m3.min 1. Organic material from the collected samples was eluted from the charcoal tubes by carbon disulphide and the BTEX component analysed by Gas Chromatography. The results showed that proportionally high levels of BTEX were present in the VOC profile and it was concluded that petroleum and its combustion products were major contributors to indoor pollution in Tehran. Also, the concentration of benzene was especially high, being some 2-4 times greater than the maximum levels recommended by many countries.

Design of an environmental assessment model on the effect of vehicle emission in greater Tehran on air pollution with economic sensitivity

Air pollution is the presence of pollutants in the atmosphere from anthropogenic or natural substances in quantities likely to harm human, plant or animal life; to damage human-made materials and structures; to bring about changes in weather or climate; or to interfere with enjoyment of life or property. With regard to the quality of air in most of the megacities of the world, vehicular air pollution plays an important role in deteriorating air quality. Air pollution in Tehran (Capital of the Islamic Republic of Iran) occurs in highly urbanized areas due to mobile anthropogenic sources which in-turn is hastened by unfavorable tohion sector is responsible for much of urban air pollution and can result in high ambient concentrations that harm people, structures, and environment. This paper examines and estimates the tonnage, concentrations and impacts of air pollutants along with control measures aimed at reducing the effect of pollutants released by transportation navigation, in Tehran.

Wind field in greater tehran area (GTA) in autumn season

Air Pollution is one of the main contaminants in industrial cities like Tehran, but it depends on many factors. One of the most important factors is wind field. Wind field shows how the pollutants transfer by convective mechanism. Tehran as the most polluted city of Iran (or may be Middle East) locates in a mountainous situation and is surrounded from two sides by high mountains and from two sides by desert. Therefore, the topography of Greater Tehran Area is so complex and needs more attention. We have studied the air pollution in Tehran from this point of view in this paper and used MEMO software for simulation of wind field in this area. The results show good agreement with experimental observations and show stronger wind from south to north and west-south to east-north in days and then night in reverse direction. It causes that the pollutants remain at urban area and the concentrations of pollutants reach to a serious level.