The effects of natural and geochemical factors depending on heavy metal contamination in nuisance dust particles were evaluated. The nuisance dust particles were sampled using passive deposit gauge method for one year from April 2010 to March 2011 and the obtained samples were measured for the total contents and the contamination levels of Fe, Mn, Cu and As using geo-accumulation index (Igeo), enrichment factor (EF) and the integrated pollution index (IPI). The results showed that, the contamination levels of Fe and Mn based on Igeo values, were uncontaminated (Igeo < 0) (variations of the Igeo index was from –3.11 to –1.751 for Fe, from –0.630 to –1.925 for Mn), while the values of Cu and As were demonstrated to have moderate contamination based on Igeo values (variations of Igeo index was from –1.125 to 0.848 for Cu, and from –2.002 to 1.249 for As). The analysis of EF also revealed minor to moderate enrichment for Mn (1.215–4.214), minor to moderately severe enrichment for Cu (2.791–6.484), and As (1.370–8.462), respectively. The variation of the IPI index also showed low to moderate level of heavy metal pollution in nuisance dust particulates (0.511–1.829). The analysis of the results also approved that the natural processes and geochemical variables (the changing meteorological parameters) can significantly affect the availability of heavy metals in nuisance dust particles in Western Iran.
