New 13C-Labeled Standard for Chemical Dispersant Used in Gulf Oil Spill
When the Deepwater Horizon oil well, a drilling rig operated by BP, exploded In April 2010 more than 180 million gallons of crude oil were released into the Gulf of Mexico. As the oil flowed unchecked from the broken well, BP was faced with the challenge of managing the spill to prevent surface water slicks, which could cause serious health and safety issues. As a last resort, the EPA, the State of Louisiana, and other federal agencies authorized the use of chemical dispersants to control the surface oil.
Chemical dispersants break up oil to form small droplets called micelles, which fall from the surface into a submerged oil plume. The submerged plume is then diluted both vertically and horizontally into the water body, where it can be further broken down by bacteria and other microorganisms. While this does not completely remove the threat of the oil, it helps to speed up the natural process of breaking down the oil, and has been considered to be less harmful than leaving surface oil slicks.
Many groups however have voiced concerns over the toxicity of the chemical dispersants, as well as the combined toxicity of dispersant and oil. BP deemed that the use of COREXIT® EC9500A (formerly COREXIT 9500) and COREXIT® EC9527A sold by Nalco Energy Services, LP, would be the best choices for diffusing the vast quantities of oil in the water. Though pressured by the State of Louisiana and the EPA to find less-toxic alternatives to the COREXIT® formulations, BP argued that due to their effectiveness and the vast amounts needed, only these products were immediately available in the quantity required. The EPA had previously authorized the use of dispersants in emergency oil spill situations, and in fact COREXIT® 9580 was used in the 1989 Exxon Valdez oil spill in Alaska1.
Restorethegulf.gov, an official website of the US government, states that as of September 2010 approximately 1.84 million gallons of dispersant have been applied to the Deepwater Horizon oil spill — 1.07 million on the surface and 771,000 sub-sea2.
Although initially held as proprietary, it was eventually revealed that the primary surfactant ingredient in the COREXIT® formulations is sodium bis(2-ethylhexly)sulfosuccinate, aka dioctyl sodium sulfosuccinate, or DOSS. In response to growing concerns about the toxicity of DOSS, CIL has synthesized a 13C- labeled standard to assist researchers with quantitative analysis of this compound in various matrices.
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CLM-8792-1.2 – Sodium bis(2-ethylhexyl)sulfosuccinate (fumaric acid-13C4, 99%) ULM-8807-1.2 – Sodium bis(2-ethylhexyl)sulfosuccinate (unlabeled) |
For current details about the Gulf oil spill, click here: RestoreTheGulf.gov
(*Corexit is a registered trademark of Nalco Energy Services)
1Wikipedia: Corexit
2Restorethegulf.gov: By the numbers