Bioremediation

Bioremediation is the process by which biological organisms are used to solve specific environmental problems, such as contamination. Bioremediation may be employed in order to attack specific contaminants, such as chlorinated pesticides that are degraded by bacteria, or a more general approach may be taken, such as oil spills that are broken down using multiple techniques including the addition of fertilizer to facilitate the decomposition of crude oil by bacteria.

Not all contaminants are readily treated through the use of bioremediation; for example, heavy metals such as cadmium and lead are not readily absorbed or captured by organisms. The integration of metals such as mercury into the food chain may make things worse as organisms bioaccumulate these metals.

However, there are a number of advantages to bioremediation, which may be employed in areas which cannot be reached easily without excavation. For example, gasoline spills may contaminate groundwater well below the surface of the ground; injecting the right organisms, in conjunction with oxygen-forming compounds, may significantly reduce the concentration of gasoline after a period of time. This is much less expensive than excavation followed by burial elsewhere or incineration, and reduces or eliminates the need for pumping and treatment, which is a common practice at sites where gasoline has contaminated groundwater.