The PI requests funds to purchase of two spectrofluorometers and a spectrophotometer needed in support of the PI's work on an existing OTIC funded RAPID for development of instrumentation for in situ EEM analysis. The goal of that project is collection of excitation emission matrix (EEM) fingerprints of oil, weathered oil, and dissolved oil from Deepwater Horizon (DWH) oil spill in the Gulf of Mexico for the purpose of determining optimal optical parameters for detection of oil compounds and improving in situ optical sensors.
Advanced spectroscopic techniques are required to determine concentrations of oil and oil byproducts and to discriminate between oil and naturally occurring organic matter in seawater. This is especially important now that the leak has been stopped and ambient concentrations are low but still at levels of chronic toxicity. The techniques to be used are: excitation-emission matrix (EEM) spectroscopy, time-resolved fluorescence (fluorescence lifetimes) at multiple excitation wavelengths, absorption, and quantum efficiency. Samples from past cruises are already on hand and awaiting analysis. Others will be collected from cruises of opportunity by research partners. The instruments requested represent a major improvement over existing equipment in terms of sensitivity, speed of analysis, specificity (addition of time-resolved capability), and overall sample analysis capacity. One of the spectrofluorometers will be dedicated to shipboard use to enable researchers to confirm results from Wet Labs in situ Safire and XMF fluorometers.
Broader Impacts
Although not funded with this proposal a post doc and graduate student will work on this project and benefit from use of this instrumentation. Instruction on instrument use, fluorescence of oil in seawater, and spectrofluorometric techniques will be incorporated into the PI's courses in the next 12 months. The PI will present a webinar on oil detection in seawater sponsored by the instrument manufacturer.
This work on this project involved acquisition of state of the art instrumentation to enable field studies for shipboard fluorescence analyses of water samples from the Gulf of Mexico in the vicinity of the Deepwater Horizon oil well accident to characterize both contaminated waters and uncontaminated background seawater. Results of this project provided full spectrofluorometric characterization of the Deep Horizon Oil and weathered oil from the spill to improve understanding of the composition of the crude oil in all stages of weathering and aid researchers in detection of oil and weathered oil across all environments of the Gulf of Mexico, from open gulf deepwaters to shallow coastal marshes and estuaries. Results have been shared broadly with partners from National Oceanic and Atmospheric Administration, U.S. Environmental Protection Agency, Florida Wildlife Conservation Commission, Florida Department of Environmental Protection, U.S. Coast Guard, oil company personel and researchers at other involved institutions and agencies via participation in several workshops and presentations at professional conferences. A postdoctoral research associate and a graduate student (female) have been involved in this project. Instruction in instrument use, fluorescence of oil in seawater, and spectrofluormetric techniques has been incorporated into Dr. Coble’s courses. Dr. Coble also presented a webinar on oil detection in seawater sponsored by Horiba, Inc. and a seminar for the local society of Geologists.
