Ecological Risk of Artisanal Mining on Heavy Metals and Radionuclide Levels of Food Crops and Fruits from a Gold Mining Area in Osun State, Southwest Nigeria

Abstract

In recent times, the percentage of gold mineral mined daily in Gold-rich regions of the country has been on the increase. A large percentage of these mining operations have been through small scale and by artisans who has dominated the scene in most part of the country and specifically in the south west part of the country. These artisanal miners are usually in the services of mining companies and do their task independently using their own techniques with the sole aim of reducing the cost of mining while aiming for higher profits. They do not sell their products through traders but operates on the basis of a contract system with companies, which guarantees the purchase of all their productions. In essence, artisanal miners make use of use mostly local or primitive technologies (Figure 1) which gives little or no consideration for environmental safety and management in addition to being time and energy consuming. The detrimental effects of Gold mining on soil, water, plants in mining environments in Nigeria and the world all over has been tremendous [Alloway and Ayres, 1993] and has always being a major subject of concern. Ranging from the degradation and devaluation of land mass, whose reclamation has always been a major problem thereby leading to loss of land value, to the high-level contribution of contaminating and harmful materials to the environment above desirable levels [Fatoki et al, 2002]. In the large-scale environmental degradation caused generally by mining of minerals, especially, Gold, those carried out by artisanal and small scale miners contributes the highest with their crude technologies and practices which results into large scale destruction of soil, vegetation, water and even air.