The overall harmful effects of particulate matter on human health depend on the exposure time and the chemical and physical properties of the particulate. There is a high exposure to fine particulates near the micro environments with heavy traffic in cities. The airborne particulate matter is consisted of fine particles (PM_2.5), coarse particles (PM₁₀) and black smoke particles sourced from different sources. In past, the black smoke method was widely used to measure the airborne particles. It is known that there is a relation between the darkness of the smoke stain and elemental carbon particles. Therefore nowadays black smoke is accepted for an indicative of primary particles sourced by combustion, secondary inorganic particles and coarse particles. The persistent strong association between adverse health outcomes of air pollution sourced traffic and the black smoke has recently prompted the World Health Organization to re-evaluation of black smoke. Black smoke can be in high concentrations especially near roads depending on the number of diesel motor vehicles.

In this study, the 24 hour samples of particulate matter in different size (PM₁₀, PM_2,5 and PM₁) were collected in densely traffic area in Istanbul and the reflectance of filters was investigated by black smoke optical method. The sampling was conducted between October 2009 and March 2010 in Yenibosna. The sampling station was 25 meters away from the D100 motorway. PM concentrations and the reflectance of the dust collected on glass fiber filters were examined. It has been estimated that the average concentration of PM₁₀, PM_2.5 and PM₁ are 98.6±64.81, 55.4±29.5 and 32.3±25.3, respectively. The daily PM concentrations were variable and the mean PM₁₀ and PM_2,5 concentration exceeded by far the daily tolerant limits in episode days. The strong relation (r=0.89) between black smokes which is the cursor of elemental carbon sourced diesel motor vehicles and fine particles were determined