Bioremediation uses microorganisms to repair ecosystems and substances, through the removal of pollution or the release of beneficial compounds. Biological systems already play an important role cleaning up damage caused by environmental disasters such as oil-spills, chemical pollution, and nuclear leakage.

Bioremediation exploits biological activities for mitigation, and wherever possible complete elimination, of the noxious effects caused by environmental pollutants. Engineered biological systems containing strong oxidative enzymes have been developed, typically bacteria and fungi, for bioremediation and used to recycle recalcitrant polymers and xenobiotic chemicals. Many plants can also be engineered to increase their ability to uptake and immobilise pollutants in the environment.