Bioremediation is the process of using living organisms to remove toxic contaminants from soil or groundwater. Many microorganisms, including fungi, bacteria, and protists, can break down organic toxins, transforming them into harmless products such as water and carbon dioxide.

During the process of bioremediation, nutrients are added to the contaminated area in order to stimulate the growth of the appropriate microorganisms, which accelerates the biodegradation of the polluting toxin. In cases in which no microorganism present is able to break down a pollutant, scientists introduce a microorganism known to degrade the toxin.

Bioremediation has been successfully used to to clean up pollutants including crude oil, gasoline, pesticides, sewage, and chlorinated solvents used in cleaning supplies. The benefits of bioremediation include lower costs and less disruption of the contaminated environment when compared to other clean up methods.