Determination of Toxic and Trace Heavy Metals in the Soil of Two Different Dumpsites: A Case Study of Ojota and Oko Filling Dumpsites, Lagos State

Abstract

: Heavy metals are metallic elements with a relatively high density that are dangerous or hazardous at low concentrations and pose a serious threat to people and the environment. The purpose of this research is to ascertain the concentrations of heavy and trace metals in the Lagos State communities of Ojota and Oko Filling. The soil samples taken from the dumpsites were treated using the digestion process. After being placed into a sampling vial, the mixed solution from the digestion process was then taken for measurement using inductively coupled plasma optical emission spectroscopy (ICP-OES). Samples taken from the dumpsites at Ojota and Igando contained 12.52% and 4.44% of moisture, respectively. The analysis's findings showed that the average concentrations of Fe (42.429 mg/L), Zn (2.070 mg/L), Ca (7.140 mg/L), P (9.06 mg/L), Cd (0.022 mg/L), Cr (0.042 mg/L), Cu (0.135 mg/L), Pb (1.280 mg/L), and Ni (0.123 mg/L) at the Ojota dumpsite were all within the WHO/FAO standards' tolerable limits and did not pose any risk. While, Fe (94.784 mg/L), Zn (11.564 mg/L), Ca (45.243 mg/L), Cd (2.838 mg/L), Cr (0.046 mg/L), Cu (0.215 mg/L), and Ni (0.22 mg/L) are the mean concentrations, respectively. In conclusion, the results from the Oko – filling dumpsites shows that the heavy metals from the soil is highly toxic and are such harmful to the environment and detrimental to human life than Ojota dumpsites.