| Story Views | |
| Now: | |
| Last Hour: | |
| Last 24 Hours: | |
| Total: | |
Corexit, Oil Dispersant Used By BP, Is Destroying Gulf Marine Life, Scientists Say
Three years ago, when BP’s Deepwater Horizon began leaking some 210 million gallons of Louisiana Crude into the Gulf of Mexico, the U.S. government allowed the company to apply chemical “dispersants” to the blossoming oil slick to prevent toxic gunk from reaching the fragile bays, beaches, and mangroves of the coast, where so much marine life originates. But a number of recent studies show that BP and the feds may have made a huge mistake, for which everything from microscopic organisms to bottlenose dolphins are now paying the highest price.
After the spill, BP secured about a third of the world’s supply of dispersants, namely Corexit 9500 and 9527, according to The New York Times. Of the two, 9527 is more toxic. Corexit dispersants emulsify oil into tiny beads, causing them to sink toward the bottom. Wave action and wind turbulence degrade the oil further, and evaporation concentrates the toxins in the oil-Corexit mixture, including dangerous compounds called polycyclic aromatic hydrocarbons (PAHs), known to cause cancer and developmental disorders.
When BP began spraying the Gulf, critics cried foul. They said Corexit is not only toxic to marine life on its own, but when combined with crude oil, the mixture becomes several times more toxic than oil or dispersant alone.
Not surprisingly, BP Chief Executive Bob Dudley defended use of the dispersant. “The toxicity of Corexit is about the same as dish soap, which is effectively what it is and how it works,” he told stockholders. “In hindsight no one believes that that was the wrong thing and it would have been much worse without the use of it. I do not believe anybody—anybody with almost common sense—would say waves of black oil washing into the marshes and beaches would have been a better thing, under any circumstances.”
BP says that Corexit is harmless to marine life, while the Environmental Protection Agency has waffled, saying both that “long term effects [of dispersants] on aquatic life are unknown” and that data “do not indicate any significant effects on aquatic life. Moreover, decreased size of the oil droplets is a good indication that, so far, the dispersant is effective.”
But many scientists, such as Dr. William Sawyer, a Louisiana toxicologist, argue that Corexit can be deadly to people and sea creatures alike. “Corexit components are also known as deodorized kerosene,” Sawyer said in a written statement for the Gulf Oil Disaster Recovery Group, a legal consortium representing environmental groups and individuals affected by the Deepwater Horizon spill. “With respect to marine toxicity and potential human health risks, studies of kerosene exposures strongly indicate potential health risks to volunteers, workers, sea turtles, dolphins, breathing reptiles and all species which need to surface for air exchanges, as well as birds and all other mammals.” When Corexit mixes with and breaks down crude, it makes the oil far more “bioavailable” to plants and animals, critics allege, because it is more easily absorbed in its emulsified state.
Sawyer tested edible fish and shellfish from the Gulf for absorption of petroleum hydrocarbon (PHC), believed to have been facilitated by Corexit. Tissue samples taken prior to the accident had no measurable PHC. But after the oil spill, Sawyer found tissue concentrations up to 10,000 parts per million, or 1 percent of the total. The study, he said, “shows that the absorption [of the oil] was enhanced by the Corexit.”
Learn more:
http://www.huffingtonpost.com/2013/04/25…57080.html
2013-04-26 14:45:18
Source:
