عنوان مقاله [English]
There is satisfying evidence that the socio-economical and built environmental conditions facing residents affect health as much as the individual characteristics of residents themselves (Jackson, 2003: 1382-83 cited in: Gomez, et al. 2015: 2314). In other words, neighborhood social and built environments have been recognized as important contexts in which health is shaped (Gomez & et al, 2015: 2314 & Ansello, 2016: 1). There is now widespread interest in the role of neighborhoods in cancer and cancer disparities (Landrine & et al, 2012: 141; Baker & et al., 2000; Krieger & et al., 2002; Singh & et al., 2003). Neighborhoods contribute to disparities in cancer and its risk factors and, hence, understanding the nature of that contribution can highlight new community-level approaches to reducing cancer disparities (Landrine, et al., 2012: 141).
Cancer is a chronic disease associated with genetic mutations caused by various exposures, most of them environmental (Dey et al, 2011: 254 and Smeltzer & et al, 2007: 1001). Meanwhile, lung cancer is the most common cancer in the world, with the majority of the cases in developing countries (Ferlayetal., 2010; Jemal etal.,2011 Cited in Guo, et al,. 2016). It is estimated that there were 1.825 million lung cancer cases globally in 2012, accounting for 13.0% of all cancer cases, and 1.59 million deaths from lung cancer, responsible for 19.4% of deaths from all cancers (Chen, et al., 2015: 307). Although personal choices, such as tobacco use, dietary and physical activity patterns, play a major role in the development of cancer, environmental and occupational factors are involved in the causation of a large number of human cancers (WHO-a, 2011: 1 & Anand, et al, 2008: 2098; Black & Hawaks, 2009: 504; Tomatis, 1990). In this regard, several studies have shown that the air pollution, physical inactivity, overweight and obesity are the key risk factors for lung cancers that urban planning can have an effective role in improving or reducing of their incidence. Given the inverse relationship of these factors with the neighborhood walkability, walking and physical activity; and due to little knowledge about the potential role of the urban built environments in reduce of the trend, the present paper seeks the modelling the spatial association of lung cancer with built environmental factors such as air pollution, urban form, access to public services and social and economic indicators in neighborhoods of Tehran metropolitan in the period of 2006-2010.
Methodology and Materials
The research is conducted using descriptive and analytical approaches. Several data and methods are used due to multifaceted nature of the research subject. In this regard, spatial statistics and geo-statistics methods are employed. PM10, PM2.5 and CO data are used that adapted from Tehran air pollution monitoring center and along with Lung cancers data (2006-2010) from ministry of health and population density from Iran statistics Center. Lung cancers data is used for identifying geographical pattern (Cluster, scattered and random) of its by using Moran’s spatial autocorrelation statistics. Also Getis-Ord general G statistics and Cluster and Outlier Analysis (Anselin Local Moran's I) statistics, respectively, are employed for detecting High/Low value clustering and mapping the cluster and outliers.
Invers Distance Weighted and kriging methods are used for interpolating point based air pollution parameters (CO, PM10, PM2.5) data. Population and employment data and Tehran’s land use and road network data are used as a mediating factors. All of mentioned statistics are done in ArcMap 10.3.1 software.
Results and discussion
Transportation is one of the most important sources of air pollutant emissions in Tehran city. In this case, urban air pollution is caused by urban transportation systems and suburban factories. Two major groups of polluting industries around Tehran are automotive and fuel production industries (Vafa-Arani, et al, 2014) that are located in west and south west of the city in the courses of prevailing winds. These two industries are the most related to the urban transportation systems. Ineffective public transportation infrastructures, non-standard streets and highways, population congestion, non-efficient urban management and planning, and several other reasons cause high traffic congestion in the metropolitan area of Tehran. Due to the closure of Tehran in northern, northeastern and partly east by mountains, this is an issue that worsen the air pollution in Tehran which brings many negative effects on lung cancer. The overall results showed that by applying the following policies, it can be overcome to the public health and air pollution problems in the medium and long-term: using urban smart growth policies and transit-oriented development approaches (TOD) in urban planning and designing practices; propagating the culture of using public transport; developing the natural, open and green zones and spaces in the city and especially in the western area of the city where there are more polluting sources.
Automobile dependence cities today are revealed in modern urban societies. The context preparation for automobile dependence phenomenon are improving living standards and tendency to well-being. This is in addition to the lack of necessary transport infrastructures and public transport options in developing countries, has brought many expenses including: exhaustion of natural resources, environmental hazards and public health problems. Despite that the numerous factors are involved in production and Intensifying the urban air pollution and its related problems, but ultimately this somehow refers to urban and suburbs land uses. Redistribution of land uses in urban spaces is one of the strategies that has been proposed to achieve the appropriate development patterns in order to reduce urban challenges and pollution, especially air pollution in different urban scales. Studies show that compact and smart growth urban forms has greatly impacts on reducing the air pollution (Bahtash & et al, 2013). Urban form and public transport network developments must comply with and support each other as much as possible. The compliance can create urban forms that encourages the use of public transport to against using private automobile and reduces the amount of air pollutants and results improving public health and lung cancer outcomes.