Bioremediation of contaminated soils: An overview

Abstract

Bioremediation has attracted attention of scientists and biotechnologists for environmental control and it employs biological agents mainly microorganisms like yeast, fungi, algae, or bacteria to treat contaminated soils or water derived in the process applied for treatment of such sites. Microbial bioremediation for in-situ removal of organic pollutants, heavy toxic metals, radionuclides, etc., can be applied successfully. Specific bioremediation technologies can also be developed based on toxicity of contaminants and the site conditions. As a component of bioremediation, application of plants for removal of contaminants from environment, known as phytoremediation, can also be made and hyperaccumulator species are capable of accumulating toxic metals about 100 times higher than those typically found in common plants. Uses of a number of biosorbents for soil treatment by uptake of ionic species present even up to tracer levels (around 10-7 M) has been demonstrated successfully. Molecular approaches can be effectively applied to enhance bioremediation. This paper presents an overview of various studies carried out on bioremediation of contaminated soils.