Assessment of heavy metals concentration in sediments of Utibete River, Eastern Obolo, Southeastern Nigeria using particle induced X-ray emission (PIXE) technique

The contamination of heavy metals constituent of sediments in Utibete River in Eastern Obolo, Akwa Ibom, Nigeria was assessed. In application of PIXE techniques, ten heavy metals, Ti, Cr, Mn, Fe, Cu, Zn, Rb, Sr, Zr and Pb, were determined from each of the sediment samples obtained at 6 sampling sites. The concentration of Fe was the highest in all the sampling sites ranged 11371.6 – 45095.9 ppm Pollution indices such as enrichment factor (EF), geo-accumulation index (Igeo) and contamination factor (CF) were employed to assess the toxicity threat posed on that part of the ecosystem by the investigated heavy metals. The results of the three pollutions indices were similar, indicating that that part of that River was highly polluted with Cr, Rb, Zr, Zn, and Mn, Pb at some point. Pollution lead index (PLI) employed for contamination assessment showed 5 of the sampling sites of Utibete River were contaminated with heavy metals determined with the exception of site 2 where there is low contamination of those heavy metals. These high inputs of the heavy metals might be due to pronounced anthropogenic influences around the studied areas. Analysis of multivariate statistics such as Pearson’s Correlation coefficient and cluster analysis were also applied to ascertain the relationship and sources of investigated heavy metals. Both positive and negative correlations were observed among some heavy metals while the cluster analysis revealed four main clusters.