Gulf Oil Spill: Do Chemical Dispersants Pose Their Own Environmental Risk?

By Andrew Moseman | May 6, 2010 9:27 am

CorexitThe storm of news about the BP oil spill in the Gulf of Mexico has reached a relative lull today, as the oil company preps for its containment dome project that it will try to execute over the next several days. With a moment to take a break from the constant news updates, reports are starting to ask: What’s with all that chemical dispersant responders have been dumping on this spill?

The stuff is called Corexit, made by the Nalco Company, and BP has now dumped about 160,000 gallons of it in the Gulf (as well as pumping 6,000 gallons more all the way down to the leak location). The dispersant particles bind to oil, sink, and are carried away by ocean currents. But while that could help keep a spill from reaching the shores en masse, it means the oil isn’t actually “cleaned up,” but rather diluted. And the dispersant chemicals themselves can be dangerous, as Nalco’s own documents (pdf) show.

The 10-page documents go into detail about compounds that must be handled with great care in their original form, that should not touch the skin and can damage lungs. Although the documents state that the potential environmental hazard is “moderate,” they say that when used as directed at sea in the recommended amounts the potential environmental exposure is “low” [The New York Times].

The company says Corexit contains no toxic metals or carcinogens. But it has refused to divulge the full chemical composition, calling it proprietary information. That’s annoyed environment groups that want to know exact what we’re putting into the sea in such mass quantity. Still, with the number of options dwindling and oil continuing to gush into the Gulf, some of those groups have come to accept chemical dispersants as the lesser of two evils.

“It’s basically a giant experiment,” said Richard Charter, a senior policy adviser with Defenders of Wildlife. “I’m not saying we shouldn’t do it; we have no good options” [AP].

Another eyebrow-raiser is the choice of chemical. While the United States is familiar with Corexit from having used it previously, reports that there are better alternatives on the market, like Dispersit.

Both Corexit and Dispersit were tested by the EPA, and according to those results, Corexit was 54.7 percent effective at breaking down crude oil from the Gulf, and Dispersit was 100 percent effective. Not only did Corexit do a worse job of dispersing oil, but it was three times as lethal to silverfish – used as a benchmark organism in toxicity testing — and more than twice as lethal to shrimp, another benchmark organism and an important part of Gulf fisheries [].

Previous posts on the BP Oil Spill:
80beats: BP Will Tow a Containment Dome to the Oil Leak Site Today
80beats: Is the Gulf Oil Spill Headed for Florida & North Carolina?
80beats: Gulf Oil Spill: Fisheries Closed; Louisiana Wetlands Now in Jeopardy
80beats: Gulf Oil Spill Reaches U.S. Coast; New Orleans Reeks of “Pungent Fuel Smell”
80beats: Uh-Oh: Gulf Oil Spill May Be 5 Times Worse Than Previously Thought
80beats: Coast Guard’s New Plan To Contain Gulf Oil Spill: Light It on Fire
80beats: Sunken Oil Rig Now Leaking Crude; Robots Head to the Rescue
80beats: Ships Race To Contain the Gulf of Mexico Oil Spill

Image: U.S. Coast Guard / Petty Officer 2nd Class Andrew Kendrick

  • Art

    I’m no expert, but shouldn’t they use the one that is more effective and less toxic? This looks like another glaring example of the shockingly low level of concern among executives and politicians for anything other than short-term monetary gain. They won’t stop until the earth is uninhabitable (mission complete?).

  • Mike Johnston

    All I can say is that dumping any amount of chemicals in the ocean is a bad bad thing, not only is there the same amount of oil in the water but now were adding chemicals…..for what??? so oil doesn’t wash up on the beaches putting pressure on the government to fix this problem..? This is one of those moments that future generations will judge us on harshly……

  • Erik

    Reminiscent of an episode of the Simpsons where they introduce snakes into Springfield to take care of the lizard problem… the lizards were initially introduced to take care of the bird problem…

  • Chris Niemann

    I live on Siesta Key. It’s properly named as a laid-back barrier island off of Sarasota. The ocean here is usually calm and warm. Now it seems as if the ocean is taking matters into its own hands. The water is far rougher than I’ve ever seen. Today my daughter-in-law was nearly swept out to sea, save for the quick actions of my son. From the above descriptions about our blatant use of chemicals, I wonder just how much the god of the sea is going to bear. Perhaps this scnerio is a harbinger of just what awaits us in 2012.

    Life, at least what we have of it, is a precarious existence at best. Some of us are blessed with physical disabilities that make us aware of this condition on a daily basis. Life is full of possibilities. As earthlings, we must learn to both accept our fate and be willing to face life as a new adventure. We are here. The answer to our future is here. Let us learn to work together as one. The Rule of One.


    Lawsuits should promply be filed against BP and all other companies and individuals involved with this global disaster and global threat. All US states, individuals on the coasts, and possibly mexico, should sue BP for this wreckless oil spill. These companies and individuals should be sued out of operation. This is another big reason amoung many others why all nations should cut ties with big oil corporations and pursue technologies such as getting electricity from magnetic generators, and having all vechicles and machines be powered by compressed air engines powered by zero point energy magnetic generators
    Go to
    Go to

  • world war 3

    Some say there will a spiritual evolution, while others mention a momentous galactic alignment, though as this is based on the location of the galactic equator, and that cannot be determined, this doesn’t seem very likely. Yet others worry about planet Niburu. So you believe in 2012?

  • Ben

    BP is killing us, not just our ocean, but us. The Chemical dispersants are killing all life in the Gulf. Think about it, the Oceans produce 90% of the oxygen we breathe! kill the algea, not just the bottom of the food chain, but a provider of the air we breathe, you are killing us! Yes I now beleive in 2012. Thank Obama for this!

  • Stephanie Dittrick

    Does anyone know how to stop the use of these chemicals? PLEASE REPLY NOW to If there is a group out there that has a petition, please write to me. I will work hard to get the word out. Thank you.


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