Abstract—The core aim of this paper is to investigate the health impacts of PM 10 in Makkah (March 2012 to February 2013). The annual average of PM 10 concentration was 195 µg/m 3 , which is greater than both EC and PME annual standards. Daily average concentrations also exceeded PME and EC standards. Furthermore, health assessment is carried out using AirQ2.2.3 model to estimate the number of hospital admissions due to respiratory diseases. The cumulative number of average hospital admission due to respiratory illnesses during the study period was 112665, cumulative number of cases per 100,000 was 2504 and the concentration- response coefficient was 2.342 (95% CI 1.899 - 2.785) per 10 μg/m 3 increase of PM 10 . The violation of daily and annual air quality standars and the results of AirQ2.2.3 suggest potential negative health impact for the residents, especially for more vulnerable groups, such as old aged, children and people with asthma and other respiratory diseases. Index Terms—Air pollution, exceedences, health effects, makkah. I. INTRODUCTION Particulate matter can be categorized into primary and secondary aerosols: i) Primary aerosols include emission from pilot power plants, auto mobile exhaust, sea spray, and dust storm, and are emitted into the atmosphere directly from the source. ii) Secondary aerosols are produced in the atmosphere from reactions involving primary or secondary gases [1]-[3]. Airborne particles, especially fine particles are found to be widely associated with health problems, [4], [5]. Rapid industrialization and urbanization in the past decade has resulted in a world-wide increase of airborne particulate matters [6], which are responsible for the reduction in visibility in urban areas [7] and can adversely affect human health [8]. The suspended particles are introduced directly into the atmosphere by natural causes, e.g. sea spray and erosion, volcanic eruptions, as well as other sources like the anthropogenic pollution sources [9], [10]. As they evolve in the atmosphere, their chemical and physical characteristics change. Such changes are carried out by atmospheric gas phase chemical reactions or through heterogeneous reactions with other gaseous species. The physical characteristics of airborne particulate matter, such as size distribution and mass concentration of the dust are more Manuscript received April 1, 2013; revised July 16, 2013. Turki M. Habeebullah is with The Custodian of the Two Holy Mosques Institute for Hajj and Umrah Research, Umm Al-Qura University, Saudi Arabia (e-mail: t_habeebullah@yahoo.com). often associated with the incidence of health hazard. In recent decades, suspended particulate matter (PM 10 and PM 2.5) have received much attention due to its potential adverse health impact and the subsequent need to better control or regulate these pollutants. The sources, characteristics and potential health effects of PM 10 and PM 2.5 are very different from each other; the latter can penetrate into the lungs more readily and is therefore more likely to increase respiratory and mutagenic diseases [11]. Particle shape and size are critical factors controlling the extent to which particles can penetrate into the respiratory tract, how and where particles are deposited, and at what rate particles are cleared form respiratory tract. Furthermore, a large number of smaller particles have a greater reactive surface area than an equivalent mass of larger particles and have a higher likelihood of reaching the deepest regions of the lungs, namely the alveolar region. Ultrafine airborne particles below 1 μm in diameter have been related to premature death, aggravated asthma, increased hospital admissions, and increased respiratory problems [12], [13]. There is a strong link between elevated particle concentration and increased mortality and morbidity [14]. Exposure to particulate matter can aggravate chronic respiratory and cardiovascular diseases, alter host defenses, damage lung tissue, lead to premature death, and possible contribute to cancer [12], [14]. Moreover, in order to understand exposures to contaminants and its associated results on health impacts [15], we need to evaluate: 1) the type of viable and nonviable particles; 2) the various sources of contaminants and the physicochemical factors leading to exposures; 3) the chemical nature of the complex mixtures in the air and the atmospheric physical (including meteorological) interactions; 4) the nature and mechanisms of the morbidity effects associated with the contaminants, including the range and distribution of sensitivity in the population; and 5) the methods of evaluation. The main aim of this research is to study the health impacts of particulate matter with aerodynamic diameter of 10 micron or less (PM 10 ) in Makkah from March 2012 to February 2013. Higher activities of pilgrims in Hajj and Umrah season can also lead to increase particulate concentrations, generated from traffic emission, fuel evaporations, aerosols transfer and various anthropogenic activities in Makkah City. Furthermore, the current study use AirQ2.2.3 model to estimate the number of hospital admissions due to respiratory diseases for each concentration range and each relative risk for the sampling site. Modeling Particulate Matter (PM 10 ) in Makkah, Saudi Arabia - A View Point of Health Impact Turki M. Habeebullah Journal of Clean Energy Technologies, Vol. 2, No. 3, July 2014 196 DOI: 10.7763/JOCET.2014.V2.122