Bioremediation is the application of microorganisms to remove unwanted organic material. The microbes metabolize the offending materials, clearing away excessive compounds and toxins (such as pesticides, chlorine, and phosphorous), and promoting an environment where healthy living things can thrive. Naturally-occurring bioremediation has been found on earth for millions of years; it is a building block of sustainable life on our planet. In recent human history, however, man has been actively applying bioremediation bacteria to remove pollutants and correct unbalanced environments. Today, bioremediation has a wide number of practical applications from corrosion control, to cleaning septic tanks and controlling wastewater odor.
Bioremediation is still being used to improve soil conditions in post-Chernobyl Eastern Europe and has been used in countering the BP Oil Spill in the gulf and radioactive contamination in Japan. Likewise, EM•1® Microbial Inoculant was widely used in phytoremediation projects to remove or reduce radiation in Asia. Studies found that the beneficial bacteria found in EM•1® enhanced the environment by increasing the presence of chlorophyll, proteins and enzymes that protect the remaining plant life from absorbing the radioactive substances. Remarkably, these studies have also concluded that the microbes are actually able to accelerate the half-life of the radioactive substances in the area. This amazing discovery goes to show that our planet’s microbes are a key resource in maintaining a life-sustaining environment.
What Are the Different Types of Bioremediation?
There are two approaches to bioremediation – in situ and ex situ. In situ bioremediation happens on site where the contamination has occurred. Ex situ involves removing the contamination for treatment elsewhere. Bioremediation can take on a number of different forms as well.
The following glossary is a brief overview of some of the most popular forms of bioremediation.
- Phytoremediation: The in situ use of plants to remove contaminants in soils, sediments or water. Phytoremediation has been used to remove pollutants from coal mining sites where chemicals have leached into the soil as well as metals in some industrial wastewater treatments.
- Bioventing: The in situ treatment of ground water using microorganisms to metabolize organic compounds. Bioventing has been used to remediate farm groundwater that has been contaminated with pesticides.
- Bioleaching: The use of microorganisms in the extraction of metals and ores. Bioleaching can be used to remove harmful metals like lead and arsenic or beneficial metals like gold.
- LandFarming: Bioremediation performed in the upper soil zone where contaminated soils are tilled and aerated in order to facilitate bacterial action and compound breakdown. Landfarming has been used to manage petroleum refinery waste, allowing oil sludge and byproducts to be managed safely.
- Bioreactor: A landfill- type environment that promotes active bacterial activity and compound decomposition, rather than simply burying waste in a “dry tomb” where decomposition is severely impeded. Bioreactors can be utilized for any number of uses where a system is required to support a biologically active environment. Specialized bioreactors can even grow cells or tissue for biochemical engineering purposes.
- Anaerobic Fermentation: The purposeful breakdown of organic plant and animal materials via microbes in the absence of oxygen. Anaerobic fermentation happens naturally when buried organic materials trapped in mud decompose at the bottom of a swamp, but it can also be applied in residential and commercial green spaces as a convenient alternative to traditional composting.
- Composting: The purposeful breakdown of organic plant and animal materials via microbes in aerobic decomposition. Composting is a fairly well-known form of bioremediation that gardeners undertake in order to provide rich nutrients to their plants.
- Bioaugmentation: The introduction of a group of natural microbial strains or a genetically engineered variant to treat contaminated soil or water. Bioaugmentation is routinely used by municipalities to treat wastewater by breaking down biodegradable organic matter.
- Rhizofiltration: The use of roots to filter water and remove toxic substances or excessive nutrients. Rhizofiltration can be used to treat ground water or surface water from construction sites.
- Biostimulation: Promoting and stimulating bacteria in a contaminated environment in order to cause bioremediation. Biostimulation can be used to treat groundwater at the subsurface to restore aquifers.