Graduate Research Fellowship: Fate and Effects of Petroleum Contamination and Chemical Dispersants in Marine Environments

Scope of Work:

In order to understand the fate of petroleum contaminants and chemical dispersants, their interactions with the environment, and the factors which influence their biodegradation, I propose a study of the Arctic marine ecosystems potentially impacted by petroleum contamination. This project seeks to: 1) assess the influence of the dispersant Corexit 9500 on oil biodegradation processes in Arctic seawater; 2) investigate the fate of Corexit in marine environments; 3) study the effects of chemical dispersants on microbial community structure and function and identify the organisms responsible for degrading each in the Arctic; and 4) to investigate the extent of the role that nutrients play in driving the biodegradation of hydrocarbons, including identifying any nutrients that are possible limiting factors. Incubations of seawater from the Arctic Ocean in the presence of Alaska North Slope crude oil, Corexit9500, and both together will be performed over a 60-day time course. Degradation of both components will be measured by GC/MS for the crude oil and by LC/MS/MS for the Corexit. Microbial analyses will be performed for each treatment using 16S rRNA sequencing using an Illumina MiSeq. Nutrients ((NO2^-, NO3^-, NH4^+, PO4^-3and SiO4^-4) will be measured flow injection analysis and total iron by atomic absorption spectroscopy. This project addresses OSRI’s“Understand” goal under the “Degradation and Toxicity” research program and technology focus area by seeking to understand the fate and effects of both spilled oil and the oil response option of dispersants in the Arctic. Additionally, this project will also address the “Inform” goal to disseminate knowledge to educate future researchers through opportunities for undergraduate engagement and K-12 outreach activities. Results from this study will help enable decision-makers to make an informed choice of appropriate response strategies in the event of a spill as well as increase our general understanding of petroleum biodegradation in the Arctic marine environment.