Risk Assessment of Heavy Metal Mining on Some Oxidative Parameters in Artisan Miners of Enyigba, Ebonyi State, Nigeria

Abstract

Efforts to eliminate communicable diseases and other third world challenges have reduced public interest on the health hazards posed by heavy metals mining. As developing countries becomes industrialized and urbanized, heavy metal pollution is likely to reach disturbing levels. This study was designed to determine the health risk assessment and oxidative parameters as a result of heavy metal mining in inhabitants of the lead-zinc area of Enyigba community in Ebonyi State. A total of 120 subjects (89 male and 31 female) comprising 60 artisan miners resident in the mining area (37.40 ± 9.08 years) and 60 control subjects (35.30± 9.59yrs) were randomly recruited into the study. Plasma levels of lead, copper and cadmium were determined using flame atomic absorption spectrophotometry. Plasma levels of malondiahyde, glutathione peroxidase, total antioxidants capacity were determined using standard biochemical methods. The risk of non-carcinogenic health of exposure to heavy metals was assessed using Hazard Index (HI) and Total Hazard Index (THI). The result showed that the artisan miners had significantly higher levels of malondiahyde, lead, copper, and cadmium compared with the control (P<0.005). On the other hand, the levels of glutathione peroxidase and total antioxidants capacity were significantly lower in the artisan miners compared to the control (P<0.005). Plasma level of lead also correlated significantly with length of exposure as measured by the number of years residing in the community (p<0.005). The HQ and THI were less than 1 while Cd was the highest contributor to risk (40.43%). In summary, there was increased concentration of these heavy metals on the artisan miners with an attendant depletion in antioxidant status. The risk assessment indicates that the inhabitants would not have significant health risk as a result of mining activities. Artisanal miners should be enlightened about safety hazards and environmental conservation.