Chemical dispersants used to clean up Deepwater Horizon spill failed

Atlantic : In the three months following the 2010 explosion on the offshore oil-drilling rig Deepwater Horizon, some 750 million liters of oil poured out of the exposed wellhead and into the Gulf of Mexico. In an effort to help microbes degrade the record-breaking volumes of oil, some 7 million liters of a dispersant called Corexit was poured into the gulf. A recent study by Samantha Joye of the University of Georgia and her colleagues questions the effectiveness of the treatment method. The researchers simulated the spill in their laboratory by collecting water from a natural hydrocarbon seep in the Gulf of Mexico and flooding the water with oil, dispersants, or both. They found that the Corexit suppressed the growth of Marinobacter, known hydrocarbon-degrading bacteria, and fueled the growth of a competitor, Corexit-degrading Colwellia. The net effect was that the dispersants actually reduced the breakdown of hydrocarbons from the oil.