Levels of thirteen polycyclic aromatic hydrocarbons (PAHs) were studied in 24 soil samples collected from the Ahdab oil field in Waset region, Iraq. The whole analysis was carried out using the gas chromatography with mass spectrometry (GC/MS) in the single ion monitoring (SIM)-mode. The total PAHs concentrations were ranged between 19 mg/kg (Site 15) and 855 mg/kg (Site of 16). The results of these samples were compared among each other according to their toxicity equivalence in mg TEQ/g concentrations and with the results of other studies. The total estimated cancer risks of exposure to PAHs in soil samples were ranged from 1.02 Â 10 À7 to 4.59 Â 10 À6. By multiplying the estimated cancer risk values by 10 6 , then the estimated theoretical cancer cases per million is between 0.0 and 5. The total estimated cancer risks in this study were within the acceptable range of excess cancer risk speciEed by the Environmental Protection Agency in the United States.

Levels of twelve Polychlorinated biphenyls (PCBs) were studied in soil samples collected from the vicinity of the Ahdab oil field in Kut area/Iraq. All the samples were extracted, cleaned up and analyzed using GC/MS for dioxin-like PCBs. The total concentration of PCBs ranged between 38 mg/kg (site 16) and 980 mg/kg (site 15) with a total mean concentration of 270 mg/kg. Pentachlorobiphenyls were the predominant PCB congeners, accounting for 57.6% of the total PCB concentration found in the soil samples. The toxicity equivalents (TEQ PCBs) in all the soil samples were found in the range of 0.01-35.66 mg TEQ/kg which is 400-fold higher than other studies. Sixteen of the 24 studied soil samples show a carcinogenity higher than the allowable concentration of 5 mg WHO-TEQ/kg.