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Bioremediation for Cleaning the Ocean Pollution

From plastics to chemical fertilizers, artificial pollutants have been found in various marine environments. Bioremediation is a term used to describe methods that clean up these pollutants by taking advantage of the natural cleansing actions of certain organisms. For example, it was determined that microbes in the Gulf of Mexico played a major role in the cleanup of the Deep Horizon oil spill.

Cleaning Up Oil Spills
- Naturally-occurring microbes are fully capable of breaking down the complex hydrocarbons found within an oil spill. These marine bacteria gobble up hydrocarbons and metabolize them, releasing carbon dioxide as a byproduct. Scientists had thought that the abundance of hydrocarbons in a spill would cause these bacteria to multiply exponentially, but a 2011 study from researchers at the Woods Hole Oceanographic Institution on the Deep Horizon spill in the Gulf of Mexico revealed that the marine bacteria simply ramp up their metabolism and do not increase in number or size.
Bioremediation of Organic Toxins via Seaweed
- In 2005, researchers from Oregon State University and Northeastern University showed that three marine seaweed could be used to remove TNT, polycyclic aromatic hydrocarbons and other organic pollutants from the surrounding water. The seaweed in the study included two temperate species, Acrosiphonia coalita and Porphyra yezoensis, as well as the tropical species Portieria hornemannii. P. yezoensis is actually cultivated by the Japanese as a crop. The researchers said the detoxifying actions of the three seaweeds are similar to those found in terrestrial plants, but more effective. The study researchers said the seaweed identified in their study could be used to protect high-risk aquaculture organisms, such as clams and oysters, that tend to accumulate toxins.
Plastic Waste
- Out on the middle of the Pacific Ocean, billions of tiny bits of plastic are swirling around in a massive circular current thousands of miles wide in a region commonly known as the "Great Pacific Garbage Patch." A 2011 study from a large team of mostly Yale University researchers showed that fungi in the genus Pestalotiopsis, which are known to cause disease in tropical palm plants, could possibly be used to break down that plastic. A study published a year later showed that the fungus was capable of breaking down plastic more than 5 percent by weight, and after one year, accomplish the complete removal of bisphenol A, a plastics additive known to cause developmental and other problems.
Eutrophication
- When large quantities of fertilizers or other chemical nutrients make their way into a marine environment, it can cause ecosystem-disrupting, excessive plant and algal growth -- a phenomenon known as "eutrophication." A 2010 study from a team of Chinese researchers showed that two types of seaweed, Gracilaria and Laminaria, could be used in the bioremediation of excessive nutrients. A 2012 study from a team of Spanish researchers found that the Pacific oyster could play a role in the bioremediation of an area affected by a commercial fish farm. Oysters effectively remove excess nitrogen from sea water by incorporating in into their tissues and shells.

Nature