After the oil
Over four months after the explosion on the Deepwater Horizon Platform in the Gulf Coast, ENVIRONMENT travels to Louisiana to look at the long term effects of the spill, the level of toxicity in the air and the future of the wetlands which are vital for life in the region.
Even before the oil spill Louisiana’s wetlands were disappearing at the rate of 15 to 35 square miles a year, or more than an acre an hour. Since the 1930s, a system of levees built for flood control and an 8,500-mile web of canals carved for navigation and energy pipelines, has caused much of the marshland to slide away.
The levees and canals prevent nutrients from the Mississippi River from being deposited. These nutrients are the soil-building and life-giving sediment the marshes need to survive. What’s more, as saltwater moves farther and farther inland, it kills salt-sensitive vegetation. When the plants die, the soft soil held in place by root systems washed away.
Louisiana’s marshes provide a vital barrier against storms and also offer up a bounty of crabs, shrimps and other seafood. But they are clearly in trouble.
Ted Falgout, is an alligator farmer in Lafourche Parish and he says that because of the increased levels of saltwater coming inland, the natural habitat for the reptiles, the marshland, is decreasing. And it’s not just for his alligators that he is worried about the changes taking place. “Fifty years ago, we had plenty of marsh, plenty of friction that would stop the storm before it got up here. Before, we very minimal levees we could protect ourselves. Now we need very high levees,” he says.
It’s somewhat of a vicious circle, the more marsh that gets washed away the greater the need for the levees, water pumps and seawalls. But, the arsenals of artificial constructions have a considerable impact on the local ecosystem. The balance is a complicated one that local authorities are still trying to strike.
Many fear that the oil spill will prove to be the final nail in the coffin for this very fertile but already fragile region. In August scientists rejoiced at the sight of a few new sprigs of marsh grass popping up among oil covered patches of wetland. Hydrocarbon-eating microbes found in the swamps help to break down the oil but the main problem comes when oil goes beneath the surface and into the underwater stems. Other fears include the effect of chemical dispersants used to break up the oil.
Across Louisiana locals and scientists alike continue to question the long term effect of, and the toxicity of the dispersants sprayed on the oil spill. BP spokesman Gerry Perreboom says that the company is “very gratified by what we know about Corexit, and those tests again are government tests, it's an EPA approved product and you know as far as we can tell, and long term research will tell but so far it doesn't seem to have long term affects."
Corexit is the dispersant chosen by BP in its attempt to stop the oil reaching the shoreline. According to a whistleblower at the Environmental Protection Agency, Hugh Kaufman, there were other less toxic dispersants available but BP has close ties to the Corexit Company. "If you read the label on the barrels it says that it is toxic to humans. As one US senator put it, BP has carpet bombed the Gulf region with this corexit much like the US carpet bombed Vietnam with agent orange," says Kaufman, noting that it could take 10 to 20 years to know the full fall out from the dispersants used this summer.
And from the toxicity of the dispersants used on the oil spill, ENVIRONMENT travels to New Orleans to look at the toxicity of houses built hurriedly after hurricane Katrina. The musicians’ village is hailed as an example of the successful rebuilding of the city after the storm but residents there have now received letters warning them of the possible presence of hydrogen sulphide in their homes. Tests for the gas have begun and some of the homeowners who have tested positive have to move out.
The root of the problem is a Chinese brand of drywall which is already causing copper pipes and wirings to corrode. Hydrogen sulphide can lead to long term security issues and it can also cause health problems.