Bioremediation: Using Living Organisms to Clean the Environment
There is no doubt that the environment is affected by the technological advances of humanity. Contaminants and pollution are abundant in our air, water, and soil. Current and subsequent generations will be tasked with cleaning up as much of the contamination as possible. To combat this contamination, bioremediation techniques are being developed by scientists using biological agents.
Bioremediation—a conjunction of the words biology (the science of living matter) and remediation (to correct a problem)—in this context means the use of biological organisms to solve an environmental contamination issue. Bioremediation uses living organisms designed to consume contaminants to help in the recovery or clean up of a contaminated medium.
The process of bioremediation might involve the introduction of new organisms to a site or the adjustment of environmental conditions to enhance degradation rates of indigenous fauna.
Why Bioremediation Is Used
Bioremediation can be applied to recover brownfields (former industrial or commercial sites) for development, and for preparing contaminated industrial liquid waste prior to discharge into waterways.
These technologies are also applied to contaminated wastewater, ground or surface waters, soils, sediments, and air where there has been either accidental or intentional release of pollutants or chemicals that pose a risk to humans, animals, or entire ecosystems.
Different approaches to bioremediation take advantage of the metabolic processes of different organisms for degradation; these approaches are also used for sequestering and concentration of different contaminants. For example, soil bioremediation might be performed under either aerobic or anaerobic conditions, and involve the optimization of the metabolic pathways of bacteria or fungi for degradation of hydrocarbons, aromatic compounds, or chlorinated pesticides.
Phytoremediation is a type of bioremediation that uses plants and often is proposed for bioaccumulation of metals, although there are many other different types of phytoremediation.
Other phytoremediation techniques are rhizofiltration, phytoextraction, phytostimulation, and phytostabilization.
The idea of bioremediation has become increasingly popular in the twenty-first century. Genetically engineered microorganisms (GEMs, or GMOs) carry recombinant proteins (modified proteins designed for specific purposes) that can hasten the breakdown process of explosives, or metabolize oil.
Other methods of enzyme optimization that do not include gene cloning techniques might be applied to indigenous microorganisms to enhance their pre-existing traits.
Bioremediation is most effective when performed on a small scale. The 1986 Chernobyl nuclear disaster, for example, was far too catastrophic to be positively affected by bioremediation efforts and is essentially beyond repair. A real-life example of bioremediation is adding nutrients to the soil to enhance bacterial degradation of contaminants and increase the rate of bioremediation on a brownfield site.
Bioremediation was used extensively to combat the devastating effects of the Exxon Valdez oil spill in 1989 and British Petroleum’s Deepwater Horizon oil spill in 2010. In both oil spills, microorganisms were used to consume petroleum hydrocarbons and played a significant role in reducing the environmental impact.
Bioremediation works where contaminants are not toxic to biological organisms.
Bioremediation provides a good cleanup strategy for some types of pollution, but it will not work for all. For example, bioremediation may not provide a feasible strategy at sites with high concentrations of chemicals that are toxic to most microorganisms. These chemicals include metals such as cadmium or lead and salts such as sodium chloride.
An Everyday Example
Bioremediation can be used at home or in commercial applications. Crime scene cleanup companies use bioremediation techniques to clean up crime scenes where there are bodily fluids. Composting is a technique used to speed up the decomposing process of yard waste, for use as a gardening tool.