Issues about application of bioremediation for cleaning up of contaminated sites

Abstract

Bioremediation as a cleaning up technology is less predictable and efficient for application on site. An apparent gap is still evident between the laboratory results with pure culture or mixed culture of microorganisms and their biochemical capability including genes and enzymes involved, and the effectiveness at cleaning up the pollutants in soil and sediment on site. Associated issues include the characteristics of the site, ageing of the chemical pollutants and sequestration into soil as one, and activity and competitive of the degradative microorganisms under the actual contaminated conditions of natural environment. Because of these, the favorable conditions for the active growth of degradative microorganisms have not been investigated well enough with the available technology, so a simple inoculation of the pure culture effective under laboratory conditions cannot guarantee an expected efficiency and positive results at on site testing. In addition, the soil or sediment physical and chemical conditions under the natural environment play an important role in the removal or mineralization of organic pollutants, but inadequate attention has been given to these factors involved from ecology. It is the objectives here to bring the attention to the bioavailable concentration of the pollutants and also the active metabolism of the organisms in situ to advance and demonstrate the effective cleaning up of contaminated sites.