What is bioremediation?
Bioremediation is a branch of biotechnology that uses living organisms such as microbes and bacteria to remove contaminants, pollutants and toxins from soil and water. Bioremediation can be used to clean up environmental problems such as oil spills or contaminated groundwater.
Key points to remember
- Bioremediation is a biotechnology discipline where microbes, bacteria and other living organisms remove contaminants from the soil and water.
- Bioremediation is traditionally used to clean up oil spills or contaminated groundwater.
- Bioremediation can be done “in situ”, on the contamination site, or “ex situ”, far from the site.
How bioremediation works
Bioremediation is based on stimulating the growth of certain microbes that use contaminants such as oil, solvents and pesticides for food and energy sources. These microbes convert contaminants into small amounts of water, as well as harmless gases such as carbon dioxide.
Bioremediation requires a combination of the right temperature, the right nutrients and food. The absence of these elements can prolong the cleaning of contaminants. Unfavorable conditions for bioremediation can be improved by adding “amendments” to the environment, such as molasses, vegetable oil or simple air. These modifications optimize the proliferation conditions of microbes, thus accelerating the completion of the bioremediation process.
Bioremediation can be carried out “in situ”, which is located on the site of the contamination itself, or “ex situ”, which is a place remote from the site. Ex situ bioremediation may be necessary if the climate is too cold to support the activity of microbes or if the soil is too dense for nutrients to be distributed evenly. Ex situ bioremediation may require excavation and cleaning of the soil above the ground, which can result in significant costs to the process.
The bioremediation process can last from several months to several years, depending on variables such as the size of the contaminated area, the concentration of contaminants, the temperature, the density of the soil and whether the bioremediation will occur in situ or ex situ.
Benefits of bioremediation
Bioremediation offers many advantages over other cleaning methods. By relying solely on natural processes, it is a relatively green method that minimizes damage to ecosystems. Bioremediation often takes place underground, where soil improvers and microbes can be pumped to clean up contaminants in groundwater and soil. Therefore, bioremediation does not disturb neighboring communities as much as other cleaning methods.
The bioremediation process creates relatively few harmful byproducts, mainly due to the fact that contaminants and pollutants are converted to harmless water and gases such as carbon dioxide. Finally, bioremediation is less expensive than most cleaning methods, since it does not require significant equipment or labor. At the end of 2020, the United States Environmental Protection Agency has historically increased bioremediation activities to a total of 1,507 sites.