Mineralogical and Chemical Characterization of Settleable Dustfall in Sulaimani City, Kurdistan Region, Iraq

Abstract

Airborne particulate matter has now become an important global environmental issue because of its many diverse effects on overall health and environmental degradation. Because of its unique complexity, solutions to this problem are challenging. The main objectives of this study were to assess the mineralogical composition and selected chemical properties of atmospheric settleable particulate materials from 15 locations in Sulaimani City, Kurdistan Region, Iraq, sampled between August 2009 and March 2010. In addition, representative samples from a heavy dust storm that affected the region on February 22, 2010, were collected from 3 locations within the city. Organic carbon, total carbonate (CaCO3 equivalent), and total free iron contents, along with pH, were determined in all samples. Mineralogical analysis of the collected samples was performed by x-ray diffraction. Carbonates made up the largest fraction of the identified minerals and were predominantly in an active form. The following abundant minerals occurred in all the studied dust samples in decreasing amounts: calcite, clay minerals, quartz, feldspar, and dolomite. The clay fraction was composed (in descending order of abundance) of palygorskite, illite, muscovite, chlorite, and smectite. Samples from the dust storm event contained gypsum minerals that were not present in the other samples and had the highest percentage of dolomite of all samples, indicating that settleable particulate matter from the meteorological dust storm had a different source than local dust.