Status of Heavy Metals Contamination in Water from Edagberi Creek, Engenni, Rivers State, South-South, Nigeria

Abstract

Samples of surface water were collected from Edagberi Creek from three different stations at intervals of two months for a one-year period. The samples were treated using standard methods and then analyzed for heavy metals concentrations using atomic absorption spectrophotometry (AAS). The metals analyzed were manganese (Mn), mercury (Hg), cadmium (Cd), lead (Pb), copper (Cu), nickel (Ni), iron (Fe), chromium (Cr) and zinc (Zn). The result of the metal concentrations in both stations and months showed the order as Hg < Cd < Pb < Cr < Cu < Zn < Fe < Mn < Ni. The values observed for Fe, Mn and Ni were higher than the WHO and NAFDAC requirement for drinking water, while those of Hg, Cd, Pb, Cr, Cu and Zn were lower than the stipulated values for drinking water by the stated agencies. Contamination factor test carried out on the different heavy metals based on their concentrations and the WHO standard showed that the studied heavy metals were at different level of contamination and pollution classification in the creek. The creek was slightly contaminated–severely polluted with Mn, while that of Hg was within contamination range, Cd and Pb fall within non-contamination to moderate contamination, not contaminated with Cu and Zn, but the creek was moderately polluted with Ni, and non-contaminated to slightly contaminated with Fe and uncontaminated to moderately contaminated with Cr. Pollution index showed that the creek is not polluted with heavy metals. Contamination degree values showed that the creek is at different levels of heavy metals contamination, while modified contamination degree indicated that the creek experienced nil to very low degree of contamination by the metals examined. From the results obtained in the creek, it is advisable that the water should be subjected to treatment before consumption. Introduction