Bacteria can be found living in nearly every habitat on the face of the earth, regardless of how seemingly inhospitable. Millions of bacteria fill the guts of humans and other animals, as well as cover the surface of plant roots. Bacteria have been found in the deepest parts of the ocean, seven miles under the surface and as high as 40 miles.
Potential benefits from the use of genetically modified organisms--such as bacteria that biodegrade environmental pollutants--are enormous. To minimize the risks of releasing such organisms into the environment, regulators are working to develop rational safeguards.