Distribution of toxic and high carcinogenic potency contaminants in urban soils of the Yenagoa city, Bayelsa state, Niger delta region, Nigeria
Yenagoa is a non-industrialized city. A total of eighteen samples were collected in order to investigate the distribution and content of the sixteen US EPA priority polycyclic aromatic hydrocarbons (PAHs) in urban soils from Yenagoa city of Bayelsa state, Nigeria .The PAH concentrations in the urban soil samples was performed using GC–MS method. The results were similar for all of the six sampling sites. The ∑PAH (sum of PAHs) concentration ranged from 1.164 mg/kg to 15.114 mg/kg (dry weight, d.w.). The Swali market axis of the city had the highest concentrations of ∑PAH. The burden of LMW PAHs follows a decreasing order: Phenanthrene > acenaphthene>cenaphthylene>naphthalene> anthracene>fluorine and while the burden of HMW PAHs follows the decreasing order: Pyrene> Dibenzo (a,h)anthracene > indeno [1,2,3-cd] pyrene (InP> Chrysene> Fluoranthene> Benzo(a)anthracene> Benzo(k)fluoranthene> Benzo(b)fluoranthene. PAH fingerprint ratios for determining both petrogenic and pyrogenic (pyrolytic) PAH accumulation was employed. The Ph/An ratio for the soil samples were 2.49, 3.47, 0.613, 1.59, 1.99 and 2.44 respectively. Ind(1,2,3-cd)P and DbahA was high in soils indicating carcinogenic risk of PAHs in the city.