Study of Soil Pollution in the Kerman Urban Areas with Trace Toxic


The study of regional variations and the anthropogenic contamination by trace toxic elements of soils is very important for environmental planning and monitoring in urban areas. Soil, sediment and rocks of urban areas of Kerman studied to assess the degree of pollution by trace elements as a consequence of anthropogenic sources. 37 samples were collected and analyzed by ICP-MS for 29 elements. These concentrations were compared with environmental investigation limits. From this study it was possible to observe that the fresh rocks (limestone) near Kerman city contain relatively low concentrations of trace elements as shown by background values. Soils of Kerman are anomalously rich in some trace elements. Most of the soil samples displayed concentrations of these element higher than natural background values that wich suggests an anthropogenic input besides the rock and sediment influences. The accumulation of these contaminants is likely to accelerate as a consequence of rapid traffic, economic and industrial growth in the urban environment of Kerman. It seems that traffic and wind- blown dust are responsible for high soil concentration in some of elements like Pb and Cu. Also the results revealed very high values of lead (>10000 ppm) and copper (>700ppm) in some soil and sediment samples. The most polluted and dangerous points are caused soils close to battery repairing stores or discarded batteries and machinery oil painting ( Pb>5000 ppm). However some of elements such as Bi, Cd, Co, Hg, Mn, Th and U, did not show any pollution in this area. Geochemical maps of some trace elements in the rock, sediment and soils were produced based on geographical information system (GIS) technology. Geochemical maps showed a increasing in concentrations of some potentially toxic elements from rural areas to center of Kerman city.