RAPID: Deepwater Horizon Oil Spill: Instrumentation Development for Hyperspectral Characterization of Natural and Anthropogenic Organic Compounds in Seawater

University Of South Florida, Tampa FL

Investigators

Abstract

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.