Lessons from the Deepwater Horizon Oil Spill

The Deepwater Horizon explosion and sinking of the BP oil rig in April 2010 resulted in the largest accidental marine oil spill in history, causing the deaths of eleven workers and releasing 4.9 million barrels (210 million gallons) of oil into the Gulf of Mexico over eighty-seven days.

Oil spills can cause oxygen depletion in the water, creating "dead zones" that can suffocate marine life, while also leading to severe ecological damage. In addition to this, the economic impact of oil spills is significant, with once-popular tourist beaches becoming uninviting and therefore having a negative impact on tourism.

The ecological and economic impact on the Gulf States of Louisiana, Mississippi, Alabama, and Florida, as well as their residents and cleanup workers, was severe. BP will incur a criminal and civil settlement cost of over $42 billion.

The spilled oil, containing 40 percent methane, posed a danger to marine life by potentially creating “dead zones” that depleted oxygen from the water. Cleanup methods included physical methods such as skimmers, booms or floating barriers, controlled burning, chemical dispersants, and bioremediation with microbes.

Some of these methods were effective, while others were found to have detrimental effects. For instance, the oil dispersant Corexit was toxic to phytoplankton, coral, oysters, and shrimp, causing mutations in shrimp, crabs, and fish, respiratory and skin irritation, mental health problems, and liver and kidney damage in cleanup workers and residents.

By contrast, bioremediation with the oil-eating microbe Oceanospirillales proved highly effective and did not create “dead zones.” A previous oil spill in Prince William Sound, Alaska, in March 1989, caused significant environmental damage, including the death of numerous sea otters, harbor seals, sea birds, and bald eagles. Recovery from that spill is estimated to take up to thirty years.