EVALUATION OF HEAVY METALS CONCENTRATION IN AKUNGBA WATERFALL, AKUNGBA-AKOKO, ONDO STATE

ABSTRACT Heavy metal is a general term that applies to group of metals and metalloids with an atomic density greater than 4 g/cm³ and are often referred to as toxic elements because of the manifestation of their toxic effects in plants, animals and man. The accumulation of heavy metals in the water directly affects aquatic organisms and also influences many other organisms through the food web, and endangers the wellbeing of the aquatic ecosystem. The study was carried out in Akungba waterfall, Akungba Akoko, Ondo State, to assess the concentrations of heavy metals in the waterfall such as iron (Fe), cobalt (Co), nickel (Ni), cupper (Cu), Zinc (Zn), Aluminum (Al) and manganese (Mn). The water sample in the study area were collected in triplicate in a one-litre plastic bottle at three different points over three months from February to April. The metals were analyzed using inductively coupled plasma optical emission spectroscopy (ICP-OES). The result revealed that the highest concentration of iron (Fe) was recorded in April (0.9677 ± 0.4900c); the highest concentration of copper (Cu) was recorded in March (0.0545 ± 0.0278a); the highest concentration of aluminum (Al) was recorded in February (0.0507 ± 0.0257a); while aluminum concentration was not detected in the month of March and the highest concentration of manganese (Mn) was recorded in March (0.0499 ± 0.0124a). The result also revealed that element such as cobalt (Co), nickel (Ni) and zinc (Zn) were not discovered in the waterfall for the three (3) months. The result showed that the concentration of iron (Fe) was greater than the standard permissible limit while other elements such as copper (Cu), aluminum (Al) and manganese (Mn) were below the standard permissible limit. The contamination factor for the elements detected showed low contamination. The study concluded that even though the heavy metal concentrations were below the permissible limits in the water, their presence may cause some severe health threats to the diversity of the aquatic organisms in their habitat and be injurious to human health after consumption. Thus, the bioaccumulation of heavy metals needs to be reduced through constant monitoring of the waterfall as well as educating the populace on the danger of the nature of their activities due to the ability of heavy metals to biomagnify over time.