Oil dispersants are complex, proprietary mixtures containing numerous components including surfactants, corrosion inhibitors, and solvents that, when mixed together, achieve the desired function of dispersing oil seawater. Understanding the proprietary composition of the Corexit dispersant formulations used during the recent Gulf of Mexico oil spill was the first barrier that had to be overcome when attempting to set up analytical methods to monitor for dispersant components in seawater and seafood.  Fast atom bombardment mass spectrometry (FAB/MS) is an older, yet ideally-suited analytical technique for the analysis of complex mixtures containing surfactants, such as well dispersants. FAB/MS required no sample preparation yet provided information on the major classes of non-ionic (Span and Tween) and anionic surfactants (sodium dioctylsulfosuccinate) present in Corexit oil dispersant formulations.  In addition, liquid chromatography with tandem mass spectrometry (LC-MS/MS) provided information that was complementary to that obtained by FAB/MS but that required additional laboratory personnel expertise and instrument time.  LC-MS/MS also was used to identify alpha- and beta-ethylhexyl sulfosuccinates, which were present in Corexit formulations so that they were also applied to the oil spill in the Gulf of Mexico.  Given the background presence of alpha- and beta-ethylhexyl sulfosuccinates in Corexit formulations, potentially as synthetic impurities or hydrolysis products, they may not be unambiguous

Analytical tools for unraveling the complex mixture of oil dispersants

245th National Meeting (2013)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.