Assessment of heavy metal pollution in urban soil in Karaj (Iran)

For study the effects of traffic and urban pollution on heavy metals concentration, 40 soil samples were collected in green areas of Karaj city with different uses and 5 samples as geochemical background were collected from unpolluted areas and margins of the city. The samples after preparation were analyzed by ICP-OES method. Statistical data were analyzed by SPSS (version 21) software. Relation of elements and pollution indexes determined for noticeable elements in karaj city. The Statistical analysis indicate that the distribution of metal such as: Cd,Cr,Cu,Ni and Zn in soil of Karaj city are similar to each other and often in the central part of Karaj city( Jahanshaher garden , Family park) Compared to other regions is more. Heavy metals in farmland soil are lower than other lands (garden, park). These findings are matching with the results reported by other researchers (from other regions of world). As, S and Zn have different distribution than other listed heavy metals. The Mean value of Zn, P, Ni, Cu, Cr, Co and Cd in the central part of Karaj city is more than other regions. PI value in the Karaj city soil for various heavy metals are respectively as: As>S>P>Zn>Pb>Cu>Ni, Cr>Cd The heavy metals pollution index for Karaj is 1.75, which is one of the moderate pollution soils.