Evaluation of Amount of Concentration and Contamination Levels of Heavy Metals Among Dust-Fall Particles in Sanandaj, khorramabad and Andimeshk

Dust storms often occur in arid and semiarid regions of the world and carry a huge quantity of materials; hence, they are recognized as one of the most important environmental issues on regional and international scales. This study aimed to evaluate the heavy metal content of dust-fall particles in the cities of Sanandaj, Khorramabad and Andimeshk in western Iran. Sampling the dust-fall particles was conducted every 10 days from 20 June 2012 over one year simultaneously in these three stations using the Deposit Gauge Method and the concentration of metals was measured using Flame Atomic Absorption Spectroscopy for Fe and Mn and Furnace Atomic Absorption Spectroscopy for Zn, Cu, As, Ag, Pb, Cd, Cr, Ni . Pollution levels for the heavy metals were then evaluated using the Geo-Accumulation Index (Igeo) and Index Enrichment Factor (EF). The results obtained for the Igeo index and EF index demonstrated that levels of Ag and Cu pollution among the dust-fall particles from the three stations were higher than for other heavy metals, while concentrations of other heavy metals were not evaluated as contaminant. Although the mean of dust-fall particles on area unit in Sanandaj station was less than Khorramabad and Andimeshk, heavy metal concentrations among the sampled dust-fall particles was relatively higher. The highest amount of dust falling on a unit area was obtained from Andimesh station, more than at the Khorramabad station and, lastly, the Sanandaj station. Moreover, the maximum and minimum levels of dustfall descending on the three stations were obtained in May and January respectively.