Environmental Reclamation with GMOs

There are several ways in which GMOs can actually help clean up the environment after it has been polluted. Here I will be focusing on a method known as bioremediation.

What is bioremediation?

Bioremediation is the use of organisms to break down waste materials into less toxic or non-toxic material in the environment. Microbes eat and digest organic substances for nutrients and energy. A common example is a composting. Leaves and other plant matter in the forest do not break down by themselves. There are billions of bacteria, fungi, and other living microorganisms that help aid in the degradation of these materials. Phytoremediation is a method that uses plants to remove toxins from the soil such as salt or harmful metals. To read more about GM bioremediation, click here.

		Microbes used for bioremediation of waste from oil spills or other harmful contaminants. The species is unknown.
(Permission pending from Gordon, 1999)

Back to top

Is it necessary for the organisms to be genetically modified?

No, not for all cases. Many organic compounds are broken down in the environment by naturally occurring microorganisms. In the Exxon Valdez oil spill in 1989, the naturally occurring microbes were encouraged to multiply and degrade the oil with the addition of fertilizers such as nitrogen and phosphorus (Biotech, 1990). However, with new developments, many different materials and chemicals are being produced that either do not break down or take an extremely long time to do so. A lot of these products get littered into the environment and cause disruption of the natural ecosystem. These wastes either prove to be toxic to many microorganisms or are just not made of a material that is possible to be broken down (Ramos, et al., 1993).

Genetically modified organisms for bioremediation have not been approved for release in the environment.

Back to top

What are some benefits of GM bioremediation?

• The organisms can be modified to have high predictability with suicide genes (Ramos, et al., 1993).
• Less disturbance: Since bioremediation is simply the introduction of microorganisms, there is very little disruption of the site to be cleaned up.
• Safety: A recent development in biotechnology is the genetic modification of organisms to clean up radioactive wastes at high temperatures (Brim, 2003). The numerous benefits to this are obvious. One of which is simply an effective new and permanent method of radioactive waste disposal. This
• Permanence: Bioremediation is a permanent method of waste disposal.
• Cheap: The estimated costs to clean up contaminated soils using traditional techniques in the US is $23 billion. The cost in European countries is estimated to be around $60 billion (Granger, 1990, Henley, 1990). These costs hardly make the "traditional techniques" feasible.

Back to top

What are some drawbacks of GM bioremediation?

The drawbacks of GM bioremediation are pretty much the same as they are for all genetically modified organisms.

• Horizontal gene transfer
• Creation of new pathogens
• Spreading antibiotic resistance
• Concern of gene flow. You can read about an example of gene flow in Bt crops by clicking here.
• Development of super weeds.
• Possibility of mutations that allow the organism to become invasive.
• Must be specifically tailored to each site. For different contaminants, different organisms are needed, and modifications are necessary.

Back to top

Back to top

Back to homepage

This website was created by
Kevin Saunders, Helen Nguyen, and Chris Wrobleski
as part of an undergraduate assignment at Davidson College.

Send questions or comments to chwrobleski@davidson.edu.

© Copyright 2004 Department of Biology, Davidson College, Davidson, NC 28035.