Analysis Of Polycyclic Aromatic Hydrocarbons And Heavy Metals Concentration In Cassava Tubers Within Okigwe Mechanic Village, Imo State.

ABSTRACT

Soils and cassava tubers in Okigwe auto-mechanic village of Imo state were investigated for presence of Polycyclic Aromatic Hydrocarbons (PAHs) and heavy metals. Six soil samples of 0 - 15 cm and 15 - 30 cm in depth were collected each, at 3 sites, in close proximity to selected automobile workshops. A distant location was used as the control site. Physicochemical properties of soils from this study area were investigated using standard methods, PAHs in the soil and cassava tubers were determined using Gas chromatography (GC) system equipped with flame ionization detector (GC/FID), Agilent Technologies 7890B, while heavy metals were analysed by Atomic Absorption Spectrophotometer (AAS). The results showed that, of the sixteen USEPA target PAHs (EPA-16) examined, PAHs showed in varying concentrations in mg kg ̵ ˡ except naphthalene that was not detected in all the soil samples. There were significant variations in the concentration of the eight (8) heavy metals (Fe, Ni, Pb, Cu, Cr, Cd, Mn and Zn) and PAHs between the experimental and control sites at 0.05 confidence level. Correlation analysis was done on physiochemical parameters with heavy metals and PAHs to establish the relationship of the data with one another. Fe had the highest mean concentration of 5278.74 mg kg ̵ ˡ and the least concentration was Cr and Cd with the mean concentration of 0.01. The concentration of total PAH components detected in the samples ranged from 122.2 mg kg ̵ ˡ to 17.1 mg kg ̵ ˡ. Implications of PAHs on health were discussed. It is recommended that mechanic villages should be sited far from residential areas, and such places should not be used as farmlands for the cultivation of edible crops. Also continuous education and trainings should be provided for automobile workers, emphasizing on the environmental implications of poor occupational waste management.