Bioremediation: Using Living Organisms to Clean the Environment

How You Can Help the Environment with Bioremediation Practices

People in Japan are being encouraged to grow sunflowers with a goal of decontaminating soil made radioactive in the wake of the Fukushima nuclear disaster. Credit: Buddhika Weerasinghe / Getty Images

Bioremediation is the use of living organisms for the recovery/cleaning up of a contaminated medium (soil, sediment, air, water). "Remediate" means to solve a problem and "bio-remediate" means to use biological organisms to solve an environmental problem such as contaminated soil or groundwater.

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 for development and for preparing contaminated industrial effluents prior to discharge into waterways. Bioremediation 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 human, animal or ecosystem health.

Approaches fo Bioremediation

Different approaches to bioremediation take advantage of the metabolic processes of different organisms for degradation or 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 is often proposed for bioaccumulation of metals, although there are many other different types of phytoremediation.

The idea of bioremediation has become increasingly popular in the 21st century. Genetically engineered microorganisms (GEMs, or GMOs), carrying recombinant proteins that can hasten the breakdown process of explosives like TNT, is still relatively uncommon due to regulatory constraints related to their release and control.

Other methods of enzyme optimization that do not include gene cloning techniques might be applied to indigenous microorganisms in order to enhance their pre-existing traits.

Effectiveness

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 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 BP’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 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.

Examples

Bioremediation can be performed on a personal level. For example, composting is something anyone can do, and it’s a fantastic way to recycle garden and yard waste nutrients to create a soil conditioner.

Nutrients can be added to the soil to enhance bacterial degradation of contaminants and increase the rate of bioremediation on the brownfield site.