Heavy Metal Contamination Assessment of Agricultural Farm Land Around Dimension Stone Areas in South West and North Central, Nigeria

Abstract

Heavy metals have been discovered to have a variety of negative effects on the food chain, the environment, and humans. Farmers in Nigeria cultivate the land for the production of indigenous food crops for human use. Various farmlands are encircled by a plethora of three-dimensional stones. Supare Akoko in Ondo State and Lokoja in Kogi State were chosen as case studies to look into the possibility of soil pollution as a result of dimension stone mining. Metals; Mn, Fe, As, Cd, Cr, Cu, Pb, Ni, Co, and Zn were analyzed in the soil samples collected over three seasons using an Atomic Absorption Spectrophotometer (AAS). The results obtained were analyzed using analysis of variance (ANOVA). The examination revealed that the range of Mn and Fe readings were 0.94-3.86mg/kg and 631.54-898.06mg/kg, respectively, and were below the allowed limits. As was having values ranging from 0.01-0.08 mg/kg. Cd had a value of 0.01-0.09mg/kg, whereas Cr was below the limit, however acceptable limits vary by nation. Cu, Pb, and Ni concentrations were 1.21-9.15 mg/kg, 0.18-0.74 mg/kg, and 0.28-1.31 mg/kg, respectively, all below the indicated limit. Season one (S1) and season two (S2) samples had Co levels above the limit for Lokoja. Heavy metal concentrations appeared to rise as the year progresses, implying pollution impacts, a drop in agricultural yields. To avoid environmental issues, continuous monitoring and assessment of the Environmental Impact Assessment (EIA) should be implemented.