Gulf of Mexico Has Greater-Than-Believed Ability to Self-Cleanse Oil Spills

The Gulf of Mexico may have a much greater natural ability to self-clean oil spills than previously believed, an expert in bioremediation said on April 8 in New Orleans at the 245th National Meeting & Exposition of the American Chemical Society (ACS).

Terry C. Hazen, Ph.D., said that conclusion has emerged from research following the 2010 Deepwater Horizon disaster, which by some estimates spilled 4.9 million barrels (210 million gallons) of oil into the Gulf of Mexico. His research team used a powerful new approach for identifying microbes in the environment to discover previously unknown bacteria, naturally present in the Gulf water, that consume and break down crude oil.

"The Deepwater Horizon oil provided a new source of nutrients in the deepest waters," explained Hazen, who is with the University of Tennessee in Knoxville. "With more food present in the water, there was a population explosion among those bacteria already adapted to using oil as a food source. It was surprising how fast they consumed the oil. In some locations, it took only one day for them to reduce a gallon of oil to a half gallon. In others, the half-life for a given quantity of spilled oil was 6 days. This data suggests that a great potential for intrinsic bioremediation of oil plumes exists in the deep sea and other environs in the Gulf of Mexico."

Oil-eating bacteria are natural inhabitants of the Gulf because of the constant supply of food. Scientists know that there are more than 600 different areas where oil oozes from rocks underlying the Gulf of Mexico. These oil seeps, much like underwater springs, release 560,000-1.4 million barrels of oil annually, according to the National Research Council.