In view of the proven efficiency of bioremediation in the degradation of compounds toxic to humans, such as benzene, toluene, ethylbenzene and xylenes (BTEX), several companies, especially those related to remediation and environmental monitoring, have shown enormous interest in the deployment of bioremediation as an option for the rehabilitation of contaminated areas. In developed countries such as the United States, Canada and several European countries, these biochemical remediation techniques have been widely used in work that is based, for example, on the treatment of soil contaminated by petroleum hydrocarbons. However, contrary to what has been done in these countries, in Brazil, bioremediation projects are still mainly theoretical, with few practical cases, but there is a real likelihood of expansion. The more important aim of this review is to indicate the advantages that this technique can offer when it is used for the degradation of compounds such as BTEX in typical Brazilian soils, whose physico-chemical characteristics contribute to the degradation of contaminants. Research shows that environmental factors (such as moisture and oxygen levels) and the availability of soil nutrients, in addition to the climatic conditions in Brazil, are quite suitable for the employment of this technique. They may pose, as an advantage, a favorable cost/benefit ratio and the opportunity for greater efficiency in the degradation of toxic and recalcitrant compounds compared to the majority of conventional remediation techniques. In summary, this review focuses on the state of the art of bioremediation techniques of contaminants in soils, presenting the most current and recent applications and innovations, as reported in the national and international media.
bioremediation; degradation; contaminants; petroleum hydrocarbons; soil
