RAPID: Assessing the impact of chemical dispersents on the microbial biodegradation of oil immediately following a massive spill

University Of California-Santa Barbara, Santa Barbara CA

Investigators

Abstract

The massive release of oil from the Deepwater Horizon incident has led to an unprecedented use of oil dispersants, which include a mix of surfactant compounds designed to dissolve oil and prevent slick formation. Previous research has shown mixed effects of surfactants on biodegradation and little is known about their effects on the ability of microbial communities to degrade the many hydrocarbon compounds found in crude oil. Hydrocarbon degrading bacteria differ in their substrate preferences, as well as in their response to surfactants, which will play an important role in determining the rate and extent of biodegradation. With funding from this Grant for rapid Response Research (RAPID), researchers at the University of California at Santa Barbara will use a combination of chemical and biological tools to track changes in the composition of the oil, changes in the microbial community, and the amount of surfactant present, in order to determine the impact of these dispersants on biodegradation. Oil quantification and composition will be determined by gas chromatography, including the use of comprehensive two-dimensional gas chromatography. Microbial community changes will be determined by analysis of the 16S rRNA gene and functional genes for hydrocarbon oxidation, and specific members of the community will be quantified with quantitative real time PCR. Surfactants will be identified and quantified with LC-MS or other techniques. Initial sampling will be shore based, with deep water and sediment sampling planned as conditions allow. The opportunity to sample in the early stages of response to this spill will provide important baseline information and enable longer term studies on the fate of oil and dispersants in the Gulf of Mexico. Broader impacts of this proposal include the involvement of an undergraduate researcher and a postdoctoral researcher, as well as collaboration with the popular news media to educate members of the public on the effects of dispersants and the fate of oil from this spill.