Evaluation of mercury contamination in soils of industrial estates of Arak city

Mercury is generally considered one of the most toxic heavy metals that rapid industrial development and industry uses of mercury cause accumulation of mercury in soil. The purpose of this study was to investigate the concentration and degree of mercury pollution in topsoil of three major industrial estates of Arak city. In this study three estates was investigated. Soil samples were collected from the depth of 0 to 20 cm. 22 samples were taken and analyzed. Mercury concentrations in soil samples were determined by Advanced Mercury Analyzer (Model; Leco, AMA 254). The mercury concentrations in soil samples range from 68.43 to 137.03 µg/ kg for soils, with a mean value of 102.07 µg/ kg. Means comparison showed significant difference among industrial town 2 with other industrial towns. Also there was no significant correlation between soil pH and Hg concentration. The result of this research showed that: Compared to earth crust, surface soils in industrial towns had higher mercury concentrations, but compared to other soils around the world, it did not show high levels of mercury and it seems that most of the sources of mercury pollution are natural. Despite the concentration of total Hg in soils are not acute, however the planning for emission control of this metal and other pollutants, with application of green plants purification technology should be considered seriously.