Evaluation of Polycyclic Aromatic Hydrocarbon from Selected Communities in Udu Local Government Area of Delta State

Abstract

The study presents a design to investigate the concentration profiles and the distribution of polycyclic aromatic hydrocarbons in soil samples within two communities in the Udu local government area of Delta State, Nigeria. Five soil samples suspected to have been contaminated with hydrocarbons were collected from the selected communities and were analyzed for polycyclic aromatic hydrocarbons using gas chromatography equippedwith a mass spectrometry detector (GC-MSD), after extraction and clean-up of the extract with n-hexane/dichloromethane using standard glass column chromatography (190/Piece Ambala, model). The results obtained from the hydrocarbon analysis gave concentration of the Σ17 polycyclic aromatic hydrocarbons (PAHs) in soil samples ranged from 0.11 to 0.83ppm with a mean value of 0.45. The order of the level of PAHs in the soil samples based on their location follows this pattern; mechanic workshop soil > road traffic soil > drainage soil > farm field soil > petrol station soil, while the appearance and profile of PAHs with respect to ring size was in the order of 3-rings > 5-rings >2-rings >4-rings >6-rings. The lower molecular weight (2-3 rings) PAHs and non-carcinogenic PAHs were the main PAHs in these soils. The isometric comparison and principal components analysis used for source apportionment shows that the PAHs in these soil originated from High- temperature combustion of biomass and fossil fuels such as wood as well as emissions from transportation.