Bioremediation is a branch of biotechnology that deals with the use of living organisms such as microbes to remove contaminants and toxins from soil and water. It can be used to clean up environmental problems such as an oil spill or contaminated groundwater.

Bioremediation processes commonly involve oxidation-reduction reactions where reduced contaminants are oxidized and oxidized contaminants are reduced. There are many different types of contaminants that can be removed using this technique: polycyclic aromatic hydrocarbons, petroleum, pesticides, chlorophenols, heavy metals, dyes, sulfates, etc.

There are two main types of bioremediation: bio-stimulation and bio-augmentation.

• Bio-stimulation involves the addition of limiting nutrients to support or stimulate native microorganisms existing in the environment that can carry out bioremediation.
• Bio-augmentation involves the addition of living cells capable of accelerating the degradation of certain contaminants.

Bioremediation has many advantages compared to other remediation alternatives. These advantages include: it is a relatively green method that causes less damage to ecosystems, creates few harmful by-products, and is cheaper than most cleaning methods, as it does not require a large amount of equipment.