The study was carried out to determine heavy metals concentration ( Fe, Zn, Pb, Cd, Cu, Mn andCr) in stream water sediments and different organs (muscles, liver and gills) of three differentspecies of fish, collected from Akamkpa local Government Cross River State, Nigeria. Figure 1shows the concentration of heavy metals in stream water and Figure 2 shows the concentration ofheavy metals in sediments. Table (1, 2 and 3) represents the concentrations (mgg dry weight) inmuscles, gills and liver respectively in different species of fish used for the study.Heavy Metals concentrations in water were found in the following order Fe 12.4 > Zn 9.7 > Mn7.8 > Pb 6.3 > Cu 3.7> Cr 1.8 > Cd 1.3. The high concentrations of heavy metals in streamwater within quarrying environment in area could be attributed to the tailing waste generatedfrom mining activities, industrial and geological weathering of the rocks. According to Khaled(2005), heavy metals enter the aquatic environment through geological weathering and humanactivities. The removal of topsoil, overburden and aggregates may affect the quality of waterrecharging of an aquifer, and excavation below the water table may lead to de-watering ofadjacent watercourses and surface water.Surface water is an important natural resource in Akamkpa Local Government Area, about 90 %of drinking and domestic water supplies in the area comes from surface water. The quantity,physical and chemical quality of surface and ground waters is affected by quarrying activities inthe area. The values of heavy metals recorded in water sample were significantly higher thanWorld Health Organization (WHO) limits. This indicates that the environment may be pollutedwith regard to the quarrying activities and geological weathering of rocks by natural processes.The concentrations of heavy metals in bottom sediment were significantly higher (p<0.05) thanthose recorded in water samples. The high level of these metals in the sediments could beattributed to the geological weathering rocks, tailing waste and mining operations in the area. Ofall the metals analyzed, iron had the highest concentration in water and the sediments.Comparing the concentrations of heavy metals in water and sediments, it can be concluded thatthe heavy metals are highly accumulated in sediment samples than in water samples. This isbecause sediments act as reservoir for all contaminants and organic matter descending from thequarry site and ecosystem. The result is in line with the previous studies in Itu river (Elijah.,2001). Carrol (2008) stated that iron appears in the river sediments as an essential component of6 EKPO, F.E; AGU, N.N AND UDOAKPAN, U. Iclay. Hamed (1998) attributed the high concentrations of trace metals in the Imo river sedimentsto high clay content of sediment and industrial activities. Comparing the concentrations of tracemetals in sandy sediments and clay sediments in aquatic environment, Udoessien (2004) reportedthat sandy sediments showed low concentrations of heavy metals than clayey sediments.
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