The Assessment of Environmental Justice in Tehran Based on Spatial Distribution of Air and Noise Pollution

The rapid development of Tehran has increased air and noise pollution which lead to the unsustainable development. Since most vulnerable groups are more exposed to pollution due to the disproportionate distribution of air and noise pollution, the main objective of this research is to investigate the relationship between socioeconomic factors and air and noise pollution distribution in order to evaluate urban environmental justice of Tehran. In order to analyze the spatial distribution of mentioned pollution, air and noise pollutants have been studied. Pollution by stationary and mobile sources were analyzed in 22 districts of Tehran using geographically weighted regression model. The results reveal that geographically weighted regression model with local R2 was 0.94, 0.59 and 0.85for the amount of pollutant emissions from domestic consumption, vehicle and motorcycle ownership respectively, with acceptable accuracy for modeling between the socioeconomic rank and air pollution source. Findings from noise pollution revealed that the model with R2 0.43 does not strongly confirm the relation between the socioeconomic rank of areas with noise pollution. This study showed that the 1,3 and 6 regions, with higher rank in terms of socioeconomic status, have the highest air pollution production, while the 18, 19, 20 regions with the lowest socioeconomic rank are more likely exposed to air and noise pollution. Hence, more vulnerable groups face urban environmental injustice. Extended Abstract 1-Introduction Urban development, regardless of environmental and social benefits, has led to severe problems such as air and noise pollution which is considered as the most complicated environmental issue in the city of Teheran leading to urban unsustainable development. As revealed by different studies, cities that are closer to sustainable development standards have a higher level of social and environmental justice. Therefore, the fair distribution of facilities and environmental risks is an essential step to achieve sustainable development standards. Since air pollution is the most serious and complicated problem in Tehran, identification of the spatial pattern of air pollution emission and exposure risks with emphasis on environmental justice is of immense importance. Other conducted research on air pollution in Tehran has not focused on social and economic issues and environmental justice. Therefore, the aim of this study is to investigate environmental justice in urban districts of Tehran by determining the relationship between air and noise pollution variables and socioeconomic indicators in 22 municipal districts of the city to fill the gap in previous studies. 2-Materials and Methods Two categories of data were required to conduct this research: 1) Air and noise Pollution Concentration Data; 2) socioeconomic status Data. Residential per capita, the average per square meter price and Total land ownership, the job status indicator and the percentage of employers and managers, higher education attainment and illiteracy percentage were reviewed in each district. Finally, the socioeconomic status ranking map was obtained by overlaying the maps of the mentioned indicators for each district of Tehran. After preparation of data sets, each set is analyzed and mapped for each of the 22 districts of Tehran by using GIS and spss16 software. In this study, the geographical weight regression method has been applied in order to investigate the relationship between air pollution and socioeconomic status. 3-Results and Discussion In order to evaluate urban environmental justice, the final socioeconomic ranking map produced for urban areas show that district 3 and 18 have the highest and lowest ranks respectively. Based on results, there was no significant correlation between air pollution monitored by air quality monitoring stations and socioeconomic status.  However, based on the modeling of air pollution, districts 1 and 3 of Tehran have higher socioeconomic status. Local R2 showed a significant relationship between the percentage of car ownership and pollutants from domestic consumption and socioeconomic rank. The results of modeling the pollutant emissions from domestic consumption, car ownership and motorcycle ownership with local R2 are 0.94, 0.59 and 0.85, respectively, with acceptable accuracy for modeling the correlation between the socioeconomic status and air pollution emission. The local R2 value was insignificant in relation to the concentration of pollutants recorded by Tehran's air pollution monitoring stations. 4-Conclusion  urban Environmental justice is one of the most crucial environmental issues in urban areas, although the importance of this subject has been ignored in Tehran. To fill this gap, the metropolis of Tehran has been selected because of its high population density, high volume of air pollution and also high social inequality. In this study, the correlation between emission of air pollutants in urban districts and socioeconomic status of the same districts was compared by quantitative spatial analysis using geographically weighted regression model. It can be concluded that the more disadvantaged and marginalized socioeconomic groups in southern districts suffer from the most air pollution risks, while groups with higher socioeconomic status in northern Tehran emit more air pollution than Southern residents. The novelty of this study was to explore the spatial correlation between socioeconomic status and air pollution, relying on the environmental justice approach. The Contribution of this research, compared to other similar studies, is considering socioeconomic issues related to air pollution by applying environmental justice approach by specialization the relation between socioeconomic status and air pollution in 22 municipal districts of Tehran.