Slick Solution: How Microbes Will Clean Up the Deepwater Horizon Oil Spill
Bacteria and other microbes are the only thing that will ultimately clean up the ongoing oil spill in the Gulf of Mexico
| May 25, 2010 |
"The last (and only) defense against the ongoing Deepwater Horizon oil spill in the Gulf of Mexico is tiny—billions of hydrocarbon-chewing microbes, such asAlcanivorax borkumensis. In fact, the primary motive for using the more than 830,000 gallons of chemical dispersants on the oil slick both above and below the surface of the sea is to break the oil into smaller droplets that bacteria can more easily consume.
For decades scientists have pursued genetic modifications that might enhance these microbes' ability to chew up oil spills, whether on land or sea. Even geneticist Craig Venter forecast such an application last week during the unveiling of the world's first synthetic cell, and one of the first patents on a genetically engineered organism was a hydrocarbon-eating microbe, notes microbiologist Ronald Atlas of the University of Louisville. But there are no signs of such organisms put to work outside the lab.
"Microbes are available now but they are not effective for the most part," says marine microbiologist Jay Grimes of the University of Southern Mississippi. At this point, there are no man-made microbes that are more effective than naturally occurring ones at utilizing hydrocarbons.
Scientists are still working to deploy known oil-eaters, such as Alcanivorax, in the form of booms laced with slow-release fertilizer and the microbes. In experiments such microbial booms ate heavy fuel oil in two months and "the experimental waste water was clean enough to be released back to the sea," says environmental geneticist Peter Golyshin of Bangor University in Wales. But "in the Gulf of Mexico, the amount of oil is simply too big. The oil gets dispersed but there is not enough [nitrogen] and [phosphorus] to feed bacterial growth."
Ultimately, it is only microbes that can remove the oil from the ocean. "In the long run, it's biodegradation that removes most of the oil from the environment in these situations," Lee says. Or, as Joye puts it, "They're clever, they're tough, they can basically eat nails…. The microbes have to save us again."
full article at : http://www.scientificamerican.com/article.cfm?id=how-microbes-clean-up-oil-spills
