Smart discussion about toxics policy reform

Why are dispersant chemicals secret?

By Dave Andrews, Ph.D., EWG senior scientist and Elaine Shannon, EWG editor-in-chief

British Petroleum, Inc. has dumped more than 400,000 gallons of chemical oil dispersants into the Gulf of Mexico near the site of the undersea gusher caused by the April 20 blowout at BP’s exploration well, which set fire to the Deepwater Horizon drilling rig and killed 11 workers.

By next week, that figure could double, at least. On Tuesday, Lamar McKay, president and chairman of BP America, Inc., told a Senate panel that its supplier, Nalco Energy Services of Sugar Land, Texas, can deliver as much as 75,000 gallons of dispersants a day for the massive environmental clean-up.

This much is well accepted: dispersants don’t make all that streaming oil vanish. As the science journal Nature reported, “they help large globs of oil ‘disperse’ into smaller pieces — hence their name — which are easier for sea-living microbes to break down.”

“Their use is a trade-off decision,” Jane Lubchenco, administrator of the National Oceanic and Atmospheric Administration, said during a telephone press conference earlier this week.

The important question, which has gone unanswered, is, are we minimizing the damage to our planet by using these dispersants, or are we adding to the mess?

It is inexcusable that we do not know the answer to this question and have decided to make the Gulf of Mexico an enormous floating science experiment. After all, we’ve been dealing with oil spills from the moment we started pumping oil. According to a 2005 National Research Council report titled, Oil Spill Dispersants: Efficacy and Effects, 3 million gallons of oil and refined petroleum are spilled annually in around U.S. waters, mostly in smaller batches.

The dispersants going into the Gulf have been around for decades. According to the NRC report, COREXIT EC9527A came on the market in the 1980s. COREXIT 9500 was introduced in the 1990’s. Both are made by Nalco and have been approved by the Environmental Protection Agency and U.S. Coast Guard for spraying on the ocean surface. (EPA has authorized limited tests of dispersants near the source of the leak, 5,000 feet below the waves, but has not given a green light to use them in volume.)

No one pretends that these or any other dispersants are environmentally neutral. “Dispersants are not the silver bullet,” EPA administrator Lisa Jackson said.

Jackson has defended the use of the chemicals on grounds they are far less toxic than petroleum and degrade much more rapidly.

That’s not much of a recommendation.

So, what is this stuff? There’s a lot the public is not permitted to know about these concoctions. The EPA has published some information about them on a list of dispersants and other agents that were okayed for use in the clean-up of New Orleans after Hurricane Katrina. But a number of ingredients are listed as “confidential” or “proprietary,” and their proportions in the mix are not disclosed.

Information provided by Nalco to EPA and the federal/BP task force on its website, known as the Deepwater Horizon Response, says that COREXIT EC9527A, contains three chemicals considered hazardous:

  • 2-Butoxyethanol
  • Organic sulfonic acid salt
  • Propylene glycol

From what we can discern, the active molecule that does the dispersing is “organic sulfonic acid salt,” a generic term for class of chemicals. Its precise chemical name is apparently proprietary. We think that once a company, or the government, or both, decides to cover the sea with this molecule, it’s time to tell us what exactly it is.

The company’s disclosure statement says, “No toxicity studies have been conducted on this product.” It also says, “Based on our hazard characterization, the potential environmental hazard is: Moderate Based on our recommended product application and the product’s characteristics, the potential environmental exposure is: Low.” But how the company has reached that conclusion isn’t clear.

Corexit 9500, the newer formulation, is made without 2-butoxyethanol. According to the NRC report, Nalco developed Corexit 9500 because it discovered that “prolonged exposure to Corexit 9527 caused adverse health effects in some responders. These effects were attributed to its glycol ether solvent (2-butoxyethanol).”

Jackson told reporters that EPA permitted BP to spray the older product, Corexit EC9527A, in the early days of the spill until sufficient quantities of 9500 could be located. She described Corexit 9500 as “more effective and more environmentally friendly.”

However, it’s disquieting that the “material safety data sheet” for Corexit 9500 warns: “Do not contaminate surface water.” Also, the document says, “Component substances have a potential to bioconcentrate.”

Energy and Enviroment Daily’s Greenwire, a leading online environmental news outlet, reported this week that Corexit may not be the best option. “Other U.S. EPA-approved alternatives have been shown to be far less toxic and, in some cases, nearly twice as effective,” Greenwire reported, adding that Nalco was once part of Exxon Mobil and still has interlocking leadership with Exxon Mobil and BP. BP spokesman Jon Pack was quoted as saying that BP was not considering or testing other products because stopping the leak and containing the loose oil “has to be our primary focus right now.”

It’s been well established that until this mother-of-all-oil-spills, BP had not developed a thoroughly researched plan for managing this sort of crisis. It didn’t know all it should about dispersants. It had to scramble to obtain sufficient supply. It may not have picked the best product for this gargantuan job. With advance planning, it might have availed itself of better options.

Most importantly, since spills are a constant threat, the oil industry should have financed far more research into dispersants. We the taxpayers seem to be shouldering the financial burden of much of that research. And yet we’re in the dark about the precise make-up and behavior of dispersants and other chemical agents that are used in very high volumes.

How many gallons of secret chemicals, exactly, will wind up being sprayed across the Gulf?

“I think it’s fair to say that when it comes to this volume, we’re in uncharted waters,” EPA’s Jackson said.

Jackson, to her credit, is blunt and doesn’t dissemble. Still, that’s not an answer Americans might have expected to hear in the 21st Century. At the moment, what we know about dispersants seems to be as murky as the Gulf’s troubled waters.

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22 Responses to “Why are dispersant chemicals secret?”

  1. J conover says:

    Has anyone thought about how toxic the chemicals will be for people with reverse osmosis water makers using gulf or gulf stream sea water? Is is safe to drink the water, swim in the water? Even if the area is not closed to use, can the dispersal agent, Corexit 9500,along with oil droplets still be in the water? Who is doing systematic testing of areas outside the known local spill area to insure safety for the public?And testing at all depths of the water. Report of a surfer outside of the spill area having a sticky,oily butter taste in his mouth–is there any danger to him?

    • dr t says:

      The supposedly proprietary composition of the dispersant Corexit 9500 is a joke being played on journalists (and to give safe harbor to regulators). Its chemical composition was disclosed years ago in toxicity studies and patent and regulatory filings, all in the public domain and all readily available on the internet. Any discussion of dispersant toxicity has to start with its composition.

      First note Corexit 9500 does not contain 2-butoxyl ethanol, unlike its predecessor Corexit 9527 (which caused adverse health effects in Exxon Valdez responders). The solvent was replaced in Corexit 9500 by propylene glycol and a mixture of food-grade (!) aliphatic hydrocarbons called Norpar 13 (n-alkanes ranging from nonane to hexadecane according to ExxonMobil rsearchers Varadaraj et al. in 1995). Relatively little toxity testing has been done with either version of Corexit.

      Second, Corexit 9500 contains two non-ionic surfactants, Tween 80 (eicosethoxy sorbitan monooleate) and the somewhat similar Span 80 (ethoxylated sorbitan mono- and trioleates). These detergents have been around for decades in hundreds of consumer and laboratory products (which doesn’t necessarily mean they have been tested).

      Third, the supposedly secret sulfonic acid salt was disclosed in the 2001 patent filing US 6168702. The basic chemical formula is that of a sulfonic and carboxylic double quaternary amine but with an allowed range of substituents making the overall composition quite variable. The patent filing shows a picture of the chemical conveying a sense of its structure. The manufacturer has the ability to vary substituents without notice.

      Toxicity testing on Corexit 9500 would be very difficult, expensive and time-consuming since it would involve a very large spectrum of marine species, the chemical attributes of the particular oil being spilled with which it interacts (here sometimes said to be low sulfur Louisianna crude and other times said to be asphalteine), depth, water temperature and waves, prior evaporation of leaked volatiles, and so forth.

      The idea — if the dispersant is applied by airplane, is that oil is dispersed from the surface water into the much greater volume of undersea water. Neither oil not dispersant goes away in the short term. It cannot be assumed that the dispersant and oil molecules ever meet up — they may simply be dumping dispersant in the ocean without getting any quantitative dispersement. The EPA just approved mixing dispersant with the leak at the source — this wild experiment could have unintended consequences such as maintaining a horizontal plume of semi-dispersed oil at mid-Gulf levels.

      Better or worse than doing nothing, nobody can say for sure. EPA has no way of getting any quantitative data under current conditions. The rate of oil leak — and changes in it for better or worse — is only vaguely known from flyovers and a table assigning thickness to 4-5 classes of oil sheen colors.

      • Elaine Shannon says:

        Der Dr. T, Thanks for your insight. I’m sure our readers will be interested. Yes, some chemicals in the dispersants have been disclosed. And yes, as EPA chief Lisa Jackson pointed out, Corexit 9500 doesn’t have 2-butoxyl ethanol. That’s most likely good. Still, the public — meaning not just journalists like me but also academic scientists — don’t know all the chemicals in this stuff. We don’t know how it behaves in the sea. What do we know? Hard to sa.

  2. Toby says:

    Because BP won’t flat out say, that the Gulf of Mexico is going to be the most toxic body of water in the world. BP is doing a fantastic job of keeping the beaches clear with booms, burning and skimming. Nobody on shore can see how bad it is out there. Most beaches are still clean.
    On another note; Tar balls are blobs of oil that froze under the pressure and cold of 5000ft of water. Some blobs float their way up to the surface. I guarantee you that BP wants to keep the tarballs coming, easier to clean up, while a lot just stay sunk on the bottom. So BP is probably jackin’ the well with some really nasty stuff, (which is why they don’t wanna tell us what it really is) in order to turn venting oil turn into tar balls. Out of sight, out of mind. That is, until they start turning up in shrimp nets across the Gulf states.

  3. Andy Reynolds says:

    Not only is the toxicity of the dispersants unknown, but their claimed efficacy in making the oil more readily broken down by microrganisms in the water column is unknown as well, or at least we must rely on the makers and users assertions of that, which seems risky at best.

    The idea that the kind of amounts of highly toxic and volatile hydrocarbons that are spewing forth unabated still, will be somehow consumed and digested into something non-toxic by marine micro-organisms is a fantasy that I am not willing to buy.

    To say we are turning the Gulf into a giant experiment is a more than a bit misleading, since we will never be able to quantify the changes, there is too little data to have a baseline to compare post-spill to, nor do we have the will or means to do the massive amount of work needed to track the changes that will result.

    This is a mess, not an experiment, just one more in the long series of insults and injuries humanity has heaped on the biosphere that we depend on for survival.

    We can however look at Prince William Sound, and the fact that the marine mammal populations there plummeted immediately after the 1989 Exxon Valdez spill, and have not recovered in 21 years. Ditto for the herring that used to spawn there in the billions. So the outlook for the gulf is not so good.

    We heard the same lame rhetoric and saw the same lack of planning, equipment, and preparedness from Exxon then as we are seeing now from BP.

    And a word of caution to any and all who might volunteer or hire on to “fight” the spill: the risks to the health of spill workers are also unquantified, so they too will be a part of a big, totally uncontrolled experiment, and I assume that BP will have an ironclad disclaimer contract with every worker that they cannot sue for health related damages after working on the spill. Look forward to every imaginable form of stress related misery, trauma and even violence in the individuals and communities that are most closely associated and affected by the spill.

    Look forward also to a lot of legal maneuvering and delaying by the corporations involved, and successful attempts to whittle the legal damages down to levels that will be an insult to the thousands of victims of this spill. The corporations have time and a legal staff of thousands to make this happen, and at present a Supreme court majority that believes corporations have the rights of “personhood”. In fact they have us by the short curlies.

  4. KJ says:

    Thank you for this information. I am curious…
    Wouldn’t it be naive to think that the oil and dispersants are confined to such a small area near Louisiana and the visible surface slicks? This has been going on for almost one month.
    We have a trip planned to Florida’s southwest coast in June. I am traveling with two young children. Even if the oil doesn’t visibly reach the beach, isn’t the water of the entire gulf already seriously polluted- especially by hundereds of gallons of dispersants? I don’t feel comfortable allowing my children to even set foot in the gulf and for this reason I am trying to cancel our trip (unfortunately at a loss of at least $1200). Am I wrong? It just seems like BP is trying to use these dispersants to make it appear as if there isn’t so much oil. What about the giant underwater plumes? How will they ever be cleaned up?
    And shame on our government for allowing the use of harmful chemicals to be widely dispersed without full testing.

    • Elaine Shannon says:

      Good questions, Kelly. They need some detailed research. I wonder if any of our readers knows more about the water quality on the Florida Gulf Coast.

    • Toby says:

      I wouldn’t wanna’ swim in that stuff. The last satellite photo I inspected clearly showed enormous plumes of toxic stuff, heading for the west coast of Florida. If you change your mind, we’re getting better weather up in Oregon now. Our water is freezing cold, but our beaches won’t be covered in BP’s mystery sludge.

      • Elaine Shannon says:

        For everyone who is following the dispersant issue —

        EPA administrator Lisa Jackson testified today about dispersants, among other things, before at the Senate Committee on Environment and Public Works. Her statement was sober and underscored unknown factors, which are, to our minds, very disquieting:

        A primary concern is to ensure the safe application of chemical dispersants. Oil spill dispersants are chemicals applied to the spilled oil to break down the oil into small drops below on the surface. The dispersed oil mixes into the water column and is rapidly diluted. Bacteria and other microscopic organisms then act to degrade the oil within the droplets. However, in the use of dispersants we are faced with environmental trade-offs. We know that surface use of dispersants decreases the environmental risks to shorelines and organisms at the surface. And we know that dispersants breakdown over weeks rather than remaining for several years as untreated oil might. But, we are also deeply concerned about the things we don’t know. The long term effects on aquatic life are still unknown and we must make sure that the dispersants that are used are as non-toxic as possible. We are working with manufacturers, with BP and with others, to get less toxic dispersants to the response site as quickly as possible.”

        — Elaine Shannon

  5. KJ says:

    Thank you, Ms. Shannon. Is there any way you can instead post a link to Lisa Jackson’s comments? The text did not come through. Thank you.

  6. Joe Prager says:

    Thanks for all your efforts on this vital issue! But, a better question is this:

    WHY ISN’T EWG and other Enviro NPGs suing the EPA and the Coast Guard in Federal Court to STOP THE USE OF THESE UNTESTED CHEMICAL DISPERSANTS???

    As a co-plaintiff in your Federal case about toxic CCA treated wood, which had a significant impact that led to a voluntary ban on this toxic and carcinogenic product, I strongly urge you to again consider legal action to stop this outrageous environmental disaster from getting worse. We can smell the oil from Gainesville, FL, and we are hundreds of miles away!

    Best regards,

    Joe Prager, Publisher

  7. Tom Engle says:

    For those of you not chemically inclined…. dispersants are just industrial strength dish detergent. The gulf will become one big sink after washing greasy pots and pans…and just as safe.

    • Toby says:

      Where’d you get that info Tom, BP?
      I’ve used Corexit before, and there’s a big old label on the side that says “Nasty stuff, don’t touch it.” And the DEQ guy that showed it to us, specifically told us to wash our hands really good, and don’t touch this stuff.

      • Tom Engle says:

        Toby, perhaps I misstated the case. I am a chemist and when I look at the structures of the surfactants in dish detergent and in the “dispersants” BP is using they are quite similar. Of course the exact ingredients and proportions are trade secrets, and while often times labels and MSDS appear to overstate risk (read an MSDS for sugar or air!!!) it would not be wise to keep ones hands stuck in undiluted surfactants and never wash it off. Undiluted they can have quite a harsh pH. The dish detergent that most people buy for use in sinks is diluted with water and sometimes buffers, so in that sense the comparison was inaccurate. If you read the box for dish detergent for use in dish washing machines…which doesn’t contact skin…you might find terminology closer to what you read for Corexit. And if you ever held dish washing machine detergent in you hands for very long you know it is harsher, it can even etch glass over time. But those effects are reduced by dilution, and the Corexit is being diluted.

        I was and am trying to give non-chemists a feeling for what the oil/water/dispersant mixture will be like. If you have ever washed super greasy pots and pans by hand in a sink full with dish detergent…you know that when you are finished there is a layer of scummy detergent/grease mixture left behind. It was suspended in the water until you let the water drain and it stuck to the sink and everything else. That layer of oily scummy residue is probably what some of the bottom of the gulf looks like now, and the living organisms. As you might know from your pot washing experience, the dispersant/detergent didn’t really “dissolve” the oil and grease or make it go away…it just made it harder to see by looking at only the top of the water.

        I think that analogy hits home with more people than complex chemistry.

        Sorry if I added more confusion than explanation.


  8. Elaine Shannon says:

    UPDATE: EPA has given BP 24 hours to come up with a safer dispersant. Check out EPA’s orders at its site.

    We have some readers with expertise out there. What do you think? Is this too little too late? Just in time? Courageous and timely? Or all/none of the above?

  9. It is nearly unbelievable that this oil spill is still not taken care of. It’s been what, like 46 days now?? All i see on the tv all day long is washed up fish, and poor birds coated in oil.

  10. Toby says:

    BP is really attacking the plume from the well-head with Corexit dispersent. Coast Guard Admiral Thad Allen reported today that they’ve crossed the “million gallon threshold” of dispersents being dumped into the ocean. Latest satellite photos show huge sheets of oil spreading out over the entire Gulf of Mexico.
    Here is a link to a non-government owned Satellite. It’s an older model, but unlike government owned satellites, they frequently update their pictures. It’s a very scary situation, so hold your breath if you want to look…

    I personally believe that BP has basically kidnapped the top officials in our government, all throughout this crises.

  11. Mary says:

    Chemical Dispersant Effects on Children???

    I am currently living in South Mississippi about an hours drive from the Gulf Coast and 3 hour drive to Venice, La. I have two young boys ages 2 1/2 and 11 months. My boys (knock on wood) have been very healthy only requiring a couple of visits to the only having been sick a few times. Ever since this oil spill, starting approximately May 10th my boys have had chronic coughs, fevers, and perpetual pink eye. Even my husband and I who never get sick have had sinus issues. These symptoms are still going on over a month later. Our doctor is clueless especially since our kids don’t attend daycare and we live in the country.
    I’ve researched the chemical being used and I haven’t been able to find information on any possible airborne effects. I’ve only found information on the effects on the ecosystem and to those who deal with the chemical directly. I really hope this is just a coincidence and that the health of my family isn’t being affected. We do however wake up to the smell of crude oil.
    If anyone has any information on this I would appreciate it greatly.


    • Toby says:

      Two chemicals getting big hits, well above normal average, on EPA air monitors in the gulf are:
      Naphthalene and Toulene
      Both types of gas are extremely dangerous. Why nobody says anything on the news is a mystery. Perhaps they don’t want to scare people, but folks need to know the truth. Especially if ya’ll are getting sick.

  12. A Mom in FL says:

    My question to be answered is the ability of this dispersant to evaporate and later rain down on us. Is it possible? Will all of our vegetation, food and water sources be contaminated? If it can rain down on us, will our city water treatment remove it? Any insite from others would be helpful.

  13. Toby says:

    Where’d Tom go? TOM!!!
    The day you find this label on a bottle of dishwashing soap. LET ME KNOW!
    We can blow it up together.

    Keep away from heat. Keep away from sources of ignition – No smoking. Keep container tightly closed. Do not get
    in eyes, on skin, on clothing. Do not take internally. Avoid breathing vapor. Use with adequate ventilation. In case
    of contact with eyes, rinse immediately with plenty of water and seek medical advice. After contact with skin, wash
    immediately with plenty of soap and water.
    Wear suitable protective clothing.
    Low Fire Hazard; liquids may burn upon heating to temperatures at or above the flash point. May evolve oxides of
    carbon (COx) under fire conditions. May evolve oxides of sulfur (SOx) under fire conditions.
    COMPANY IDENTIFICATION : Nalco Energy Services, L.P.
    P.O. Box 87
    Sugar Land, Texas