Screenshot from online video about dispersants by Nalco, Corexit's manufacturer
Screenshot from online video about dispersants by Nalco, Corexit’s manufacturer

The two types of dispersants BP is spraying in the Gulf of Mexico arebanned for use on oil spills in the U.K. As EPA-approved products, BP has been using them in greater quantities than dispersants have ever been used in the history of U.S. oil spills.

BP is using two products from a line of dispersants called Corexit, which EPA data appear to show is more toxic and less effective on South Louisiana crude than other available dispersants, according to Greenwire.

We learned about the U.K. ban from a mention on The New York Times’ website. (The reference was cut from later versions of the article, so we can’t link to the Times, but we found the piece elsewhere.) The Times flagged a letter that Rep. Edward Markey, chairman of the House Subcommittee on Energy and Environment, sent to the EPA on Monday. The letter pointed out that both the Corexit products currently being used in the Gulf were removed from a list of approved treatments for oil spills in the U.K. more than a decade ago. (Here’s the letter.) 

As we’ve reported, Corexit was also used after the Exxon Valdez disaster and was later linked with human health problems including respiratory, nervous system, liver, kidney and blood disorders. One of the two Corexit products also contains a compound that, in high doses, is associated with headaches, vomiting and reproductive problems.

Given that the dispersants are EPA-approved, the choice of which ones to use was left to BP, which had stockpiled large amounts of Corexit and is now ordering more. 

BP has defended its choice to use Corexit. A BP spokesmancalled the product “pretty effective,” and said it had been “rigorously tested.” It is not testing other dispersants, he said, because it’s focusing on stopping the spill. Mani Ramesh, the chief technology officer for Nalco, which makes Corexit, disputed claims that the product is harmful to the environment, telling Reuters that Corexit’s active ingredient is “an emulsifier also found in ice cream.”

Dispersants like Corexit break up oil into droplets that linger longer in the water instead of collecting at the surface. The choice to use them is inherently an environmental tradeoff. Their use in the Gulf spill has limited the instances—and images—of oil-covered seabirds, but has kept the effects of the spill mostly underwater. Scientists have discovered giant plumes of dispersed oil in the deep waters of the Gulf, though the EPA has said “there is no information currently available” to link the dispersants to those deep-sea plumes. The plumes are now fast approaching the Gulfloop current, which could spread the oil into the Atlantic Ocean.

In a hearing this afternoon, EPA Administrator Lisa Jackson told the Senate Committee on Environment and Public Works that the EPA is working with BP to get less toxic dispersants to the site as quickly as possible, according to Kate Sheppard of Mother Jones.

The EPA, while recognizing that long-term effects on the environment are unknown, has said that the federal government will regularly analyze the effect of dispersants, and that it will discontinue the application of dispersants underwater “if any negative impacts on the environment outweigh the benefits.”