The damage caused by an explosion on 20th April at the Deepwater Horizon oil well caused an oil spill at 1,900 feet depth. By the time the well was capped 85 days later, 172,000 gallons of oil had gushed out.
Crude oil is a mix of hydrocarbons of varied toxicity and consistency. We saw tragic images of distressed animals coated in sticky oil, dolphins, sea turtles, fish, crabs, and brown pelicans and laughing gulls. Some oiled birds were cleaned successfully, but most died. By May 2010 oil had coated and penetrated sediments in estuaries and marshes in Louisiana. Salt marsh grasses, crabs, mussels, oysters, and worms were coated in oil. In the long term, how will these species be affected?
Oil lingers in the Gulf, some in plumes of droplets, probably produced by interaction of oil with a dispersant Corexit. Is Corexit toxic to marine life, especially the countless millions of larvae and micro-organisms in the plankton? Yet some of these micro-organisms, specialist bacteria, can break down oil.
Comparisons are made with the 1989 Exxon Valdez oil spill. Are there any other relevant oil spills to help us predict long-term effects of the Gulf oil spill in coastal sediments?
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