My latest group presentation on Acid Deposition for Biol 4095 allowed me to explore various methods for fixing the damage caused by pollutants. I found bioremediation to be very interesting, especially since it was the first time I came across this solution. Further research helped explain how this process worked and all the pros that came with it.
What is Bioremediation?
Bioremediation is the use of organisms to clean up contaminated soil and groundwater. Examples of such organisms include microbes, fungi and protists but the most commonly used are bacteria that live naturally in the environment.
Bioremediation encourages the growth of these organisms that use contaminants (oil and other petroleum products, solvents, and pesticides) as a source of food and energy. The contaminants are digested into harmless substances such as water and gases such as carbon dioxide and ethene.
If these organisms do not exist in the affected site, or are too few in number, ‘bio augmentation’ can be used to add more. It is also important for the site to have the right temperature, nutrients, and food to allow the microbes to flourish and perform their intended job.
It may take a few months or even several years for microbes to clean up a site, depending on several factors. For example, bioremediation will take longer where contaminant concentrations are high, or trapped in hard-to-reach areas, like rock fractures and dense soil, or even if the area is too large or too deep.
Why Use Bioremediation?
Bioremediation has the advantage of using natural processes to clean up contaminated sites. A major advantage includes how cost effective it can be. Because it may not require as much equipment, labor, or energy as some cleanup methods, it can be cheaper. Another advantage is that contaminated soil and groundwater are treated onsite without having to dig, pump, and transport them elsewhere for treatment. This is especially useful if the site exists in residential and busy, populated areas.
Because microbes change the harmful chemicals into small amounts of water and gases, few if any waste byproducts are created. Bioremediation has successfully cleaned up many polluted sites and has been selected or is being used at over 100 Superfund sites across the country.
The Basque Institute of Agricultural Research and Development Neiker-Tecnalia is looking at ways to remedy soils contaminated by organic compounds containing chlorine, mainly insecticides, such as DDT, aldrin, dieldrin, endosulfan, etc. Although most of these chemicals are or in the process of being banned, their effects still linger. Bioremediation is carried out and used to restore an environment altered by contaminants to its natural state.