Ecological Risk Assessment and Source identification of PAHs by PMF model in petroleum contaminated soils; West of Kermanshah province

Abstract

We collected soil samples at 23 sites from the petroleum contaminated soils (PC) in the west of Kermanshah province to investigate the sources and ecological risk of polycyclic aromatic hydrocarbons (PAHs). In this study, source apportionment has been carried out using Positive Matrix Factorization (PMF).The total PAHs concentration, have a mean value of 92.79 mg/kg, ranging from 7.37 to 609.67 mg/kg in PC soil samples. The average abundance order of different PAH ring compounds are 3 rings > 5+6 rings > 4 rings> 2 rings. The ecological risk assessment of PAHs revealed that all of the PAHs levels were higher contents than the effects range low (ERL) value and show higher concentrations than the ERM values, except for Pyr, Chr, BaA, BbF, BkF and BaP in the soil samples. The result of benzo (a) pyrene equation (BaPeq) values indicates that the carcinogenic potency of PAHs should be given more attention due to the impending environmental risk in the study areas. Based on the PMF analysis four sources of PAHs are identified including coal combustion (21.48%), vehicular source (13.74%), unburned petroleum (20.84%) and creosotes (43.92%).Therefore, it was concluded that petroleum activities were major sources of PAHs in west of Kermanshah province.