Polycyclic Aromatic Hydrocarbons in Asphaltic Coastal Bitumens (Tar Balls) in the Eastern Stretch of the Niger Delta Region of Nigeria

Abstract

The concentration, distribution and source of polycyclic aromatic hydrocarbons (PAHs) of nineteen tar ball samples from a part of the eastern coastal line of the Niger Delta were appraised by classical and instrumental methods. The concentration of the PAHs in the tar ball samples ranged from 0.00 – 117.82ng/g. Their concentrations fell into three distinctive classes: >30ng/g; < 30ng/g and no detectable PAHs. Phenanthrene was the most widely distributed PAH among the low molecular weight (LMW) PAHs (di& tricyclic PAHs) while pyrene was the most widely distributed among the high molecular weight (HMW) PAHs (tetra&pentacyclic PAHs). The LMW PAHs were more predominant than the HMW PAHs. The ratio of Phenanthrene and anthracene, a source indicator depicted a high intrusion of combustion products into the tar ball matrix. This is supported by the chromatograms which also reflected different stages of weathering. Crude oil spillage and gas flaring should be curtailed.