The aim of the present work was to study the feasibility of using bioleaching for the solubilisation of metals from solid waste streams and by-products of copper, steel and recycling industries. Optimal process conditions were tested using iron and sulphur oxidising acidophiles in shake flasks at 25°C. The effects of inoculum, ferrous iron, sulphur, chloride ion, pH, and the type of waste material on metal solubilisation were evaluated. Solubilisation of metals was mainly achieved through acid attack due to the formation of sulphuric acid by sulphur oxidising bacteria. Addition of ferrous iron and chloride ion did not enhance solubilisation.