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Background: The objective of the study is to determine the nature and the anthropogenic sources of the detected metal pollutant in the sediment of the Ikpoba River. Also, to study the distribution trend and the ecological and health risks of the analyzed metals. The metals were extracted from the sediment through aqua regia digestion and analyzed with an atomic absorption spectrometer. A total of six metals was quantified. Results: The distribution of the average concentration of metals showed that Cd < Cu < Co < Pb < Ni < Fe. The ecological risk assessment showed the values of geo-accumulation (igeo) and contamination indices of the metals to be zero except for Fe. This is an indication of zero pollution of the aquatic system by all detected metals except Fe. However, the enrichment factor (EF) of the metals has values greater than 1.5 in some sampling areas and less than that in others. Furthermore, the values of the ecological risk index (ERI), pollution load index (PLI), and potential ecological risk (PER) of the detected metals were all less than one. The sediment quality guidelines (SQGs) were all low for the tested metals. The human health risk assessment revealed the hazard quotient (HQ) and hazard index (HI) of the analyzed metals to be less than 1, while the carcinogenic risk was also noted to be less than 10-6. Conclusions: Children's ADD values were higher than adults' through dermal and ingestion exposure routes, indicating that children are more vulnerable to metals risk than adults. Furthermore, the values of the EF and multivariate statistics showed the sources of the metals to be a mixture of anthropogenic and natural, with anthropogenic activities leading. However, despite the low ecological and human health risk posed by the various metals, Cd was discovered to be a potential carcinogen and ecological risk to children, and the biota of the studied stream, if released, persisted unabated

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The present study investigated the potentials of two blended organic manures (Fish and pig wastes) as biostimulating agents in restoring induced crude oil pollution in soil samples. 200g of soil sample was obtained and polluted with 10% (w/w) of Bonny crude. 30g of the blended mixture of the organic manure (fish and pig wastes) were added to the polluted soil samples. The bioremediated soil was subsequently analyzed for physicochemical properties, total Petroleum hydrocarbons (TPH), polycyclic aromatic hydrocarbons (PAH), heavy metals and endogenous oil degrading fungi populations on weekly basis for a period of five weeks. From the results obtained, bioremediation with the blended organic manure significantly improved the levels of nitrogen, P, K and organic matters when compared with the control. The concentrations of PAH and TPH were significantly reduced following treatment with the organic remediants in a time dependent manner. The results also revealed that there was a significant increase (P<0.05) in the fungal load on the amended soil sample following the five weeks treatment plan. Thus, the study suggests that a combination of fish and pig wastes could serve as an excellent biostimulating agent for the remediation of crude oil polluted soils.