Distribution of Polycyclic Aromatic Hydrocarbons (PAHs) in Soil Samples from Regions Around Loda-Irele Bitumen Field, Nigeria

Polycyclic aromatic hydrocarbons (PAHs) were investigated in soils of Loda-Irele (geographical coordinate 6°29'0″N 4°52'0″E), Nigeria. Soxhlet extraction technique was used for soil PAH extraction using dichloromethane as extracting solvent. PAHs in the samples are estimated using Gas chromatography-mass spectrometer (GC-MS). The PAH concentrations were higher than 110 ppb in most samples, pointing to anthropogenic and petrogenic sources of the pollutants. Most PAH concentrations fall within the expected limits for a rural environment and below the threshold limit. However, 12.08 and14.68 ppb for Benzo(e)pyrene and 5.62 ppb for Indenol (1, 2, 3 – cd) pyrene exceeded the expected limit. Dominating 4 - 6 ring PAHs showed the PAHs were from pyrolytic sources. The concentrations of PAHs are not significant (p>0.05) compared to maximum allowable concentrations in soils.