Determine the Efficacy of Salinity on Bioremediation of Polluted Soil by Phenanthrene

Phenanthrene is one of the Polycyclic Aromatic Hydrocarbons (PAHs) that are formed during the incomplete combustion of fossil fuels, oil pollution and different process of oil and gas plants. PAHs-contaminated area have increased a health risk to humans and environments due to toxicity, carcinogenicity, hydrophobicity and their tendency to accumulation in soil and sediment and their entrance to food chain. Bioremediation is an effective method for removing toxic pollutants from soils such as Phenanthrene. The main object of this study is the assessment of the effects of salinity on the efficacy of the process of bioremediation on polluted soils by Phenanthrene. The bare soil of any organic and microbial pollution was first polluted artificially to the phenanthrene then a nutrient solution with two minimum and maximum concentrations of salinity were added to it in order to have the proportion of 10% w:v (soil: water). After that a microbial mixture which was enable degradation the phenanthrene added to the slurry and aerated. After the extraction of phenanthrene by ultrasonic, the residual concentration in the soil was analyzed by GC. In the conditions that salinity concentration was maximum, the microbial growth has a longer lag phase than the minimum salinity. The findings from extraction process by GC depict the removal percentage of maximum and minimum salinity in 56th %70.5 day and %71.8, respectively. In In spite of the longer log phase of maximum concentration of salinity and according to GC results, there was just a little difference between two solutions. Therefore it reveals that salinity can increase the lag phase but havent any inhibitory effect on Phenanthrene removal.