Heavy Metals in Soils around a Major Cement Factory in Southern Nigeria: Ecological and Human Health Risks

ABSTRACT

This study was carried out to evaluate the ecological and health risks associated with metals in soils around major cement company in southern Nigeria. Twenty-one soil samples including a control sample were collected around the cement company. Metals such as Cd, As, Co, Cr, Cd, Pb, Ni, Fe, and Zn were analysed using Atomic Absorption Spectrometer (AAS). Results showed that the average concentration of Cu, Co, Cd, Cr, Ni, Pb, Zn is 7.95 mg/kg, 0.50 mg/kg, 3.00 mg/kg, 1.00 mg/kg, 0.95 mg/kg, 2.00 mg/kg and 6.80 mg/kg while the average concentration of Cu, Co, Cd, Cr, Ni, Pb, Zn around the cement production area is 6.30 mg/kg, 1.50 mg/kg, 1.75 mg/kg, 2.09 mg/kg, 2.62 mg/kg, 6.40 mg/kg and 3.58 mg/kg respectively. The concentration of metals in this area was lower than the recommended standards but higher than those in the background soil. Contamination assessment of metals in soils of Okpella area revealed that they pose a very high degree of pollution and deterioration of the environment. Furthermore, ecological risk assessment revealed that the metals pose medium ecological risks. Health risks assessment uncovered that children residing in this area are prone to non-carcinogenic health risks through dermal contact with Cobalt in contaminated soils of the area. The statistical evaluation showed that metals in the soils might have originated from related sources. It is recommended that proper environmental monitoring of the area be carried out reduce its impact on the health of the populace.

Keywords: Ecological risk, Cement processing factory, Health risk, Contamination assessment, Heavy metals