Calculating Pollution Indices and Health risks of Heavy metals in Surface Soil at Tikrit City

The present study focuses on the assessment of pollution indices and health hazards due to heavy metals in surface soils at Tikrit city. The concentration of heavy metals were ranged: Zn (37 -104) mg/kg, Cu (16 – 28) mg/kg, Pb (21 – 56) mg/kg, Co (17 – 23) mg/kg, Cr (94 – 132) mg/kg, Ni (82 – 149) mg/kg and Mn (402 – 537) mg/kg. The values of enrichment factor (EF) and contamination factor (CF) indicated that, the pollution of studied area by Ni and Pb was due to anthropogenic activity. Value of pollution load index (PLI) was higher than unity which indicate pollution of the area by heavy metals. By applying health risk assessment model, it is found that value of hazard quotient (HQ) of each element of non carcinogenic heavy metals is less than 1 for three exposure pathways (i.e. ingestion, dermal contact and inhilation, indicating no health hazards for both children and adults. It is also concluded that children are more susceptible for potential hazards than adults, as well as ingestion pathway is more serious than other exposure pathways. Cancer risk value of Cr in surface soil is the highest, indicating high potential carcinogenic hazards through inhilation of soil particles, while cancer risk value of both Co and Ni indicated moderate potential carcinogenic hazards, whereas cancer risk value of Pb was the lowest, suggesting no carcinogenic hazards through ingestion pathway.