Heavy metals such as; Nickel (Ni), Lead (Pb), Chromium (Cr), Iron (Fe), Cadmium (Cd), Manganese (Mn), Zinc (Zn), Copper (Cu) and Vanadium (V) were assessed in water, sediment and crab (Callinectes amnicola) from three stations along Ijala creek. The creek receives effluents discharges from Industrial activities and few human settlements within the area. Samples of water, sediment and crab (Callinectes amnicola) were processed and analysed for heavy metals using various analytical techniques which the results showed that the heavy metal contamination in sediment is more than that of the crab and the crab accumulate these metals than the water. Cadmium had the highest Biological Concentration Factor (BCF) when compared with the Biological Concentration Factors of other metals. Atomic Absorption Spectrophotometer was used in determined the selected heavy metals and the concentration of heavy metals obtained were in these orders: water had Fe> Zn> Mn> Cu> Ni> Cd> Cr> Pd> V; sediment had Fe> Zn> Cu> Ni> Cd> Mn> Pb> V and crab had Fe> Cd> Cr> Zn> Cu> Mn> Ni> Pb> V. The concentration of metals in water, sediment and crab had shown a significant difference (P < 0.05). Fe had the highest concentrated among the heavy metals in the three sample matrix (water, sediment and crab) and its value exceeded the background value and also above the target and intervention values for sediment micro-pollutant standard. The contamination of Ijala creek by heavy metals increased in this order; station III> station II > station I. The study observed fluctuation in heavy metal concentration in the creek and suggested stringent environmental monitoring of the creek.
Keywords: Pollution, Heavy metal, Ijala creek, Water, Sediment and Crab, Contamination.