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David L. Valentine, University of California Santa Barbara
A fresh oil slick from the Deepwater Horizon spill, during June 2010. Note that one drop of detergent was added to the oil slick, forming the cleared circle. A chemical of such dispersants lingers in the deep ocean, a new study found.
When nearly 800,000 gallons of a chemical dispersant were injected into the oil gushing from the busted wellhead on the bottom of the Gulf of Mexico during last year's Deepwater Horizon disaster, nobody knew for sure what would happen. Now, scientists are getting their first answers, and the results are mixed.
Tests for a key component of the chemical concoction reveal that the dispersant worked its way into the oil-laden plume in the deep ocean, and stayed in the deep ocean. But the chemical did not degrade as much as scientists thought it would.
"It is hard for me at this point to say whether or not it is bad or good that it stuck around," study lead author Elizabeth Kujawinski, a chemist at the Woods Hole Oceanographic Institution in Massachusetts, told me today. She and colleagues were surprised that little or no biodegradation of the dispersant substance had occurred.
Molecule measurements
The team analyzed concentrations of a molecule called DOSS (dioctyl sodium sulfoscuccinate), which makes up about 10 percent of the dispersant solution. In May and June of last year, it was present in the oil plume in parts-per-million concentrations. More than 640,000 pounds of DOSS were injected into the deep ocean from April to July.
By September, the plume had drifted 200 miles away from the wellhead, and concentrations of DOSS were detected there in parts-per-billion concentrations. The finding suggests that the degradation of the molecule was insubstantial relative to other factors such as simple dilution, Kujawinski said.
While the researchers expected the molecule to degrade faster, they note that there is a dearth of data on the fate of the molecule in seawater and dispersants in the deep ocean, making any interpretation scientifically tentative. Instead, they see this study as a foundation for future studies.
"By knowing how the dispersant was distributed in the deep ocean, we can begin to assess the subsurface biological exposure, and ultimately what effects the dispersant the dispersant may have had," another study co-author, David Valentine from the University of California at Santa Barbara, said in a statement. "The results indicate that an important component of the chemical dispersant injected into the deep ocean remained there and resisted rapid biodegradation. This knowledge will ultimately help us understand the efficacy of the dispersant application as well as the biological effects."
Valentine said that the decision to use the dispersants at the sea floor "was a classic choice between bad and worse," and that scientists will need to do more studies on the chemicals' biological effects. "The deep ocean is a sensitive ecosystem unaccustomed to chemical irruptions like this, and there is a lot we don't understand about this cold, dark world," he said.
Environmental impact
The existing scientific literature indicates that toxic concentrations of DOSS are about 1,000 times more concentrated than the highest concentration Kujawinski and colleagues observed, which suggests the concentrations of the molecule they detected in the deep ocean are not toxic to the ecosystem there.
Kujawinski noted, however, that she's unclear on how long organisms were exposed to the chemical in those toxicity studies. In any case, most if not all of those studies were conducted on coastal organisms such as blue crab.
"One of the concerns about this deepwater application is that it affects a different group of organisms, deep sea corals, deepwater fish, and so on," she told me. "And the question is whether or not they would be as sensitive, more sensitive, or less sensitive, as the organisms that were actually studied."
Findings were published online today in the American Chemical Society journal Environmental Science & Technology.
More on the oil spill and dispersants:
- Oil dispersants an environmental 'crapshoot'
- Is dispersant still being sprayed in the Gulf?
- Skeptical public fears oil spill health issues
- NOAA, FDA to test seafood for dispersants
- Some experts skeptical of Gulf oil findings
In addition to Kujawinski and Valentine, the co-authors of the report in Environmental Science & Technology, "Fate of Dispersants Associated With the Deepwater Horizon Oil Spill," include Melissa C. Kido Soule, Angela K. Boysen, Krista Longnecker and Molly C. Redmond.
John Roach is a contributing writer for msnbc.com. Connect with the Cosmic Log community by hitting the "like" button on the Cosmic Log Facebook page or following msnbc.com's science editor, Alan Boyle, on Twitter (@b0yle).
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Wonderful, not knowing these effects beforehand. It reminds me of a short story by Kurt Vonnegut, one where a scientist creates a chemical called Ice-9. Gee, wonder what this will do to the environment?
Obviously, as responsible persons/scientists shouldn't we know what these chemicals do before we dump tons of them into the environment??
It's not the scientists at fault, though some of them are toadies in the problem. The real problem is the regulators, company officials and government. BP and the government were preventing independent (unbiased) studies on the area. There were many reports of university and independent scientists having their samples taken then being threatened by officials patrolling the area. When scientists are employed to do studies on an area that was affected by their employer, their observations cannot be accepted as factual data because they have a bias perspective. I'm sure BP had their scientists claim that the dispersants were safe before any real study was done and the government allowed them to do it because the government knows very little about actual scientific study.
And there are greenies that want to dump stuff in the ocean and pump stuff into the air to try to change the atmosphere because they believe that man is somehow this one time responsible for the natural climate cycles that the Earth repeatedly goes through.
If you put iron in the ocean to promote algae growth, we know its not going to cause long term damage and the best thing for the atmosphere seems to be removing CO2 from it, none of these things are going to kill jobs on the contrary they are going to make more jobs, the problem is whether they stay in the US or go overseas. The Iphone is a great example made in China; it could be made here with all the pollution, health & safety standards if we impose tariffs on imports from places that don’t have those costs, they will then clean up their act just like Japan did workers wages will raise and we will have a level playing field. The wind mills for the windmill farms that are in plans to be built across the US are made in China, GM Ford Chrysler, Toyota many companies that would hire American workers here in the US could make them it’s only cheaper to make them elsewhere because of Free Trade we have standards that cost money and they don’t.
We need Fair Trade
economykiller, you're nothing but a dumb loser who gives environmentalists a bad name. They were always opposed to such chemicals being added to the ocean, and had strongly warned against it. The chemicals were added anyway. If they weren't, oil eating bacteria would've easily and naturally taken care of the problem. Now it's a bigger mess.
No, the greenies don't want to pump stuff into the air either. On the contrary, they want you to stop pumping so much CO2 into the atmosphere, and please also stop spewing garbage on the Internet. Don't you realize how much the CO2 levels have increased, or are you just too daft?
Those would be terribly misled greenies.
I agree, why do these greenies believe the scientific consensus which consists of 98% of climatologists? All of this mounting evidence and scientific data is obviously a conspiracy.
Ironic thing is that this particular surfactant or dispersant is also approved by the FDA as a stool softener as in a laxative and it is a very large volume item. Makes you wonder.
Ironic thing is that particular surfactant or dispersant is also approved by the FDA as a stool softener as in laxative and it a rather large volume item on the market. Makes you wonder.
How in the H. are you going to map this particular-nasty-garbage-spread when our sneaky military/ contractor flyboys in C-130's are still dumping the stuff?
Come on flyBoy heros, let me see a video of one of you all bathing in a drum of COREXIT9500, JD2000, SAF RONGOLD or DISPERSIT SPC.
You're late on the report dude. Corexit was already known to drop to the bottom of our ocean and cover over all life thus killing it. What a bunch of real losers..hey, wait a minute..we ARE the real losers!
This is why we shouldn't be using dispersants at all. It wasn't enviromentalist asking for it contrary to all the posters here, it was the companies trying to hide the real volume of oil being released into the sea. If you let the oil come to the surface it can be dealt with. Now we have miles long and wide oil pools on the bottom of the ocean killing everything in it's path. And all this dispersant dissolved in the water doing killing off life as well. Do you honestly think coral can survive in dispersant laden water?
Right wingers say it makes no sense to subsidize renewable energy, that it's not economically viable. Well, neither is the continued reliance on fossil fuels. It's ruining our small planet, threatening our health, and causing wars. We pay for these costs in many ways beyond the gas station and utility company, and if you included this in the economic calculation, renewable energy would be a bargain. And yet, according to the Environmental Law Institute, "Fossil fuels benefited from approximately $72 billion (from 2002-2008), while subsidies for renewable fuels totaled only $29 billion."
We are subsidizing our own destruction, and investing heavily in our own demise. Powerful corporate interests have brought us to this point for short-term financial gain. It's high time we stopped investing in yesterday's dirty energy sources, and start on a path to a clean, renewable energy future. Such investment would be a boon to our economy, and help us wean ourselves from our heroin-like dependency on imported oil, so we can make foreign policy decisions based on what's right, instead of insuring our next fix.
Put all the costs of fossil fuels on the table, and then compare it to renewables.
How about no subsidies for any businesses? What if we just lowered the job-killing excessively high corporate tax rates for everybody. Then, we could eliminate the need for all the special interests and special industry vote buying concessions loaded into our ridiculous tax codes.
......well......duh.
Never mind that the dispersant is still there - the oil is still there too. It's just a matter of time before it starts to collect again.
There were other choices, ones that were safer & cheaper but Corexit was used for a specific reason(s). That reason(s) is still veiled, but what other country allows the use of Corexit?
And the EPA was worried about sand levees(to keep the oil from reaching shore) would harm the environment!