Assessment of the heavy- metal pollution in sediments of the Roein karstic basin

One of the most important environmental issues which can affect the health of plants, animals and humans is soil pollution by the concentration of the heavy metals. The increase of heavy metal concentration can occur due to the natural processes or human activities. The present study deals with examining and assessing the concentration and contamination of the heavy elements in the sediments.  Roein    basin in Esfarayen area was selected for this purpose and the concentration of 11 heavy metals, including As (Arsenic), Cd (Cadmium), Co (Cobalt), Cr (Chrome), Cu (Copper), Fe (Iron), Mo (Molibden), Ni ( Nickel), Pb (Lead), V (Vanadium) and Al (Aluminum) were measured in 42 samples and the correlation of the elements was examined. The results showed that there is a significant correlation between the copper and iron content (0.99), iron and aluminum (0.93), cobalt and copper (91), cobalt and iron (0.89), chrome and nickel (0.88), copper and aluminum (0.85), cobalt and aluminum (0.82), arsenic and aluminum (0.72), nickel and lead (0.7). Then, the contamination factors such as enrichment factor, contamination factor, modified contamination degree, pollution load index and geo-accumulation index were computed and assessed. All the indexes were calculated except the enrichment factor which depend on the elements existing on the crust of the earth and the arsenic is categorized as strong, suggesting that although the eleven elements studied contain various contents, they all are categorized as the non-polluting and therefore, there is no significant contamination in terms of heavy elements concentration in the area. Since, there is currently a higher increase in the heavy metal concentration, higher control shall be applied regarding the agricultural and industrial activities.