Evaluation of heavy metals in soil from automobile mechanic Village Dutse, Jigawa State, Nigeria

Soil contamination by heavy metals is a worldwide environmental problem. Some heavy metals pollutants are released from the activities in the auto-mechanic workshops and have various effects on human health as well as the environment. It is important to determine the presence and concentration level of the heavy metals in the soil. This research was aimed to determine the level of some selected heavy metals and physicochemical parameters of the soil sample. The soil samples were digested with nitric and hydrochloric acid and heavy metals were analyzed from digested samples using atomic absorption spectrometer (AAS). Results of the atomic absorption spectrophotometric (AAS) analysis of soil samples revealed that sample is contaminated with Ni, Zn, Mn, Fe and Cu with concentrations level (mg/kg) range between (0.75 - 5.55), (0.30 - 0.40), (1.00 -1.42) (0.80 - 1.30) and (0.05 - 0.60), respectively. Other metals such as As, Cd, Cr also contaminated the soil with concentrations (mg/kg) ranged between (0.12-0.76), (0.13-01.13) and (0.11-1.30), respectively. The results were compared with the standard set by National Environmental Standards and Regulations Enforcement Agency (NESREA). The research concluded that the anthropogenic activities at auto-mobile workshops contaminate soil with heavy metals which may have a direct or indirect effect on human. Further studies should be conducted to ascertain the effects of those metals on human, plants, groundwater, and environment.