Sources of Polycyclic Aromatic Hydrocarbons in an Environment Urbanised by Crude Oil Exploration

Polycyclic Aromatic Hydrocarbons (PAHs) sources in Kolo Creek soil were predicted using Diagnostic Ratios (DRs) of parent PAHs [Phe/Phe+Ant; Fluo/Fluo+Pyr; BaA/BaA+Chry and Ind/Ind+BghiP]. The study was conducted in the dry and rainy seasons of 2008. The dry season had higher concentrations of PAHs than in the rainy season. Five ringed PAHs were dominant all through the study period. Applying cross plots of the DR values, revealed that in the rainy season, the PAHs were mainly of combustion origin, while in the dry season, it was a combination of petroleum and combustion sources, based on the activities domiciled in the sampling station during the period of study. Comparison of DR values obtained from this study with literature values enabled the further classification into combustion and/or petroleum sources. The combustion sources of PAHs were mainly as a result of Grass/Wood and petroleum combustion while the petroleum sources were as result of combined petroleum products. The predicted PAHs sources corresponded with the prevailing human activities in the vicinity, especially samples collected near a petrol station and an abattoir.