GLOBAL CHALLENGES

Can Biotech Help Clean the BP Oil Spill?

Michael Steinhart | Date: 05-05-10 | Comments

Bioremediation is a promising solution for safe cleanup of oil spills and ground contamination. But is it ready for prime time in the Gulf of Mexico?

A few weeks ago, I posted an item about mushrooms and plants that can remove pollutants and contaminants from soil, in a process called bioremediation. The topic has garnered significant attention since the April 20 Deepwater Horizon drilling rig explosion.

As the oil slick creeps toward the Gulf Coast, BP, the federal government and environmental groups are scrambling to protect the fragile coastal ecosystem.

The rig was drilling 130 miles southeast of New Orleans, and the resulting spill is pumping some 210,000 gallons of oil per day into the Gulf of Mexico.

British Petroleum, owner of the well, is using numerous methods to attempt to contain the spill and reduce the harm it causes to the Gulf Coast. These include:
- Controlled burns of dense oil pockets.
- Booms (portable barriers) that physically block the oil from flowing past. Hundreds of thousands of feet of boom are currently being used offshore in the Gulf, aimed at protecting the shorelines of Port Sulphur and Venice, La.; Pascagoula and Biloxi, Miss.; Mobile, Ala.; and Pensacola, Fla.
- Chemical dispersants that break the oil spills down into miniscule droplets, which are more easily consumed by naturally occurring microbes in the ocean.
Bioremediation of oil spills is more complicated at sea than it is on land, and it�s also more complicated because the spill has not yet been contained. There are human-engineered microbes that can digest the oil toxins, but experts agree that natural microbes do a better job. The next step, then, is to accelerate these microbes� growth and digestive capacity by adding sulfate or nitrate fertilizers to the water.

"Nature has already evolved microbes better at consuming hydrocarbons than anything we could grow, and when you go out in the ocean and dump some new organisms on a spill, it already is colonized with those better, natural microbes," says microbiologist Ronald Atlas in an interview with USA Today. "What we are really doing is adding fertilizers to these locations to speed the natural process." Experts estimate that, when fertilized, the oil-digesting microbes can work three to five times more quickly, yielding measurable results in a year or so.

Sounds straightforward, doesn�t it? Unfortunately, introducing nitrate-based nutrients into the ocean disrupts the ecological balance and can cause other problems down the road.

"The concentration of chemicals used to clean up sites contaminated by oil spills can cause environmental nightmares of their own," says Terry Hazen, a microbial ecologist in Berkeley Lab's Earth Sciences Division, in a Science Daily report.

According to Hazen, who has studied the long-term effects of the Amoco Cadiz spill of 1978 and the Exxon Valdez spill of 1989, untreated areas of coastline recover naturally within a few years, but chemically treated areas sustain more long-term damage.

What does he suggest? "From a cleanup standpoint, right now we should be using sorbents to take up as much of the oil as possible," Hazen says. "Then we need to gauge how quickly and completely this oil can be degraded without human intervention."

Sorbents have been used in smaller-scale spills, such as the November 2007 Cosco Busan spill in the San Francisco Bay. Some groups reuse natural fibers�human and animal hair, wool, fur, feathers�to create highly absorbent booms and mats that soak up oil effectively. One environmental group called Matter of Trust collects hair clippings from salons for this purpose.

To bring the discussion back to mushrooms, volunteers in San Francisco used hair mats from Matter of Trust to soak up oil from the bay, and then used colonies of oyster mushrooms to absorb the oil from the mats. The mushrooms take about 12 weeks to absorb the oil, breaking the hair mats down into nontoxic, compostable material.

It�s going to take a lot of hair to absorb the millions of gallons drifting toward the Gulf Coast, but should the oil reach shore, BP employees, government agencies and volunteers will have to use every tool at their disposal to remediate the contamination.