Analysis and Sources of Polycyclic Aromatic Hydrocarbons in Soil and Plant Samples of a Coal Mining Area in Nigeria.

This study analysed coal, plant and soil samples collected from the vicinity of Okobo coal mine in Nigeria for Polycyclic aromatic hydrocarbons (PAHs) and evaluated the sources of the PAH contamination in the environmental samples. The environmental samples were extracted by sonication using a ternary solvent system and analysed for 16 PAHs by gas chromatography-mass spectrometry (GC-MS). The results of the analysis of the samples identified some of the target PAHs. The ranges of total concentrations (in mg/kg) of PAHs in the coal, plant and soil samples were, 0.00-0.04, 0.00-0.16 and 0.00-0.01 respectively. The evaluation of the results of the PAH analysis of the environmental samples using diagnostic ratios revealed that the PAHs in the soil samples were mainly of petrogenic origin, while those in plant samples indicated mixture of petrogenic and pyrolytic origins.