Assessment of Clean up Levels Due to Inhalation of Polyaromatic Hydrocarbons in Contaminated Soils

Abstract

Polyaromatic hydrocarbons (PAHs) are types of hazardous and carcinogenic compounds that their inhalation could have adverse effects on human health. Leakage from oil refinery facilities such as storage tanks, underground oil pipelines and evaporation ponds are the means of contaminants leaking to the environment, particularly to soils and groundwater. In this research, due to the widespread oil's leakages occurring in Tehran oil refinery in Shahre-Ray, Iran, soil samples were collected from different contaminated locations in the south of the refinery. The samples were analyzed for two PAH compounds, namely benzo(a)pyrene and benzo(k)fluoranthene. Physical and hazardous characteristics of the contaminants were evaluated based on geotechnical characteristics of the soils located near to the refinery. More ever the soils' clean up levels at the site were calculated via inhalation of these volatile carcinogenic organics. Results of the study indicate that maximum concentrations of the soil samples were 638 ppm and 651 ppm for benzo(a)pyrene and benzo(k)fluoranthene, respectively. Benzo(a) pyrene concentration in the soil was higher than the clean up level of 50 ppm, indicating that the soil should be treated at the site for this compound. Benzo(a)pyrene is chemically complex contaminant. Its' hazardous characteristics could be reduced by destructing of its structure to more simple chains. Thus, phyto-remediation technique was recommended for treatment of this contaminant at the site.