This MRI RAPID grant will allow for the development of a laboratory facility that can employ pyrolysis coupled with gas chromatography-mass spectrometry (Py-GC/MS) to characterize oil, water, sediment, and oil-contaminated seafood samples from the Alabama coastline that is heavily contaminated by the Deepwater Horizon oil spill. The Deepwater Horizon oil spill has discharged an enormous amount of oil into highly sensitive Gulf waters. This has resulted in severe contamination of Alabama's and other Gulf coast beaches, wetlands, and bays. The long-term impacts of this catastrophic event are simply unknown. This MRI investment is timely and urgent in light of the recent Gulf of Mexico oil spill.
The Environmental Engineering faculty at Auburn University is committed to conducting peer-reviewed research to address various environmental assessment and remediation problems related to this event. Specifically, this MRI RAPID award will enable the following six research topics that are directly related to the Deepwater Horizon oil spill event: 1) developing an ecological baseline database for the Gulf region; 2) understanding the fate and transport of dispersant-mixed crude oil using wave-tank experiments; 3) understanding the influence of dispersants on the kinetics of the crude oil dissolution process; 4) quantifying the influence of dispersants on oil biodegradation kinetics; 5) assessing the impacts of dispersants and dispersant-mixed crude on marine microfauna; and 6) development of seafood safety test methods. The PIs have initiated preliminary oil characterization and biodegradation studies in their laboratory. These research efforts require a GC/MS facility to characterize the crude oil and its components.
The data generated using this instrument will help the PIs better understand the impacts of the oil spill and will also help devise innovative methods to mitigate the impacts. Understanding the fate and transport of crude oil components and its impact on water quality, sediments, seafood and the overall coastal ecosystem is critical to understanding the overall long-term impacts of the oil spill on the Gulf Coast economy. The PI is currently working with a diverse team consisting of sociologists, marine biologists and ecologists to explore various long-term socio-economic issues related to the spill.
The objective of the research instrumentation grant is to develop an analytical facility for analyzing various types of Deepwater Horizon oil spill wastes that are continuing to wash ashore along Alabama’s pristine white sandy beaches. We investigated several GC/MS vendors and selected to buy Agilent’s 7000 B Quadrupole GC/MS/MS system. This is an advanced instrument for conducting target compound analysis on complex environmental samples. Use of the MS/MS reduces sample preparation time and provides high level of selectivity and sensitivity. We also purchased Agilent’s PAH analysis kit which allowed us to quickly develop methods for analyzing PAH-contaminated field samples. In addition, we have installed CDC’s pyrolysis probe which can act as a direct sample injector to analyze high molecular weight compounds present in crude oil. As part of this research effort, we have completed over ten field trips in the past twelve months to collect various forms of weathered crude oil and tar ball samples that washed along Alabama’s beaches. We have also worked closely with a local beach community (Orange Beach, Alabama) and supported their restoration and recovery efforts. The samples collected by the City and our research team from various beaches have been labeled and archived in our storage facility. We have developed clean-up protocol for processing these samples and have analyzed several of them. One of the most import dataset collected using our new instrument was published in the research report titled: "Is submerged Deepwater Horizon oil degrading offshore--comparison of the chemical signatures of tar mat samples deposited by Tropical Storm Lee in September 2011 with oil mousse samples collected in June 2010." The findings of this study are important in a number of ways. First, the GC/MS/MS data helped us question the validity of the widely held belief that submerged oil from the Deepwater Horizon accident is substantially weathered and thus depleted of most PAHs. GC/MS/MS fingerprints have indicated that the submerged oil has not degraded and hence may continue to pose some level of long?term risk to near-shore ecosystems. The field study also has demonstrated the potential for remobilization of trapped oil by future storm events. Finally, the laboratory data questioned the commonly used phrase "tar mat" for referring to the partially weathered oil materials that are trapped at the bottom of the near-shore environment, all along Alabama beaches. Using the GC/MS/MS generated MRM data we have made a case that the submerged materials are not highly weathered recalcitrant tars (implied by the term "tar mat"), instead they are oily material and are similar to emulsified oil mousse that washed ashore along Alabama beaches in June of 2010. Therefore, we proposed that referring to these submerged material as submerged "oil mats" rather than "tar mats" is a more appropriate terminology. We are continuing our field sampling efforts, and also developing new characterization methods for processing complex matrices such as fish tissues. These chemical characterization efforts have enormous implications for understanding the long term human and environmental risks posed by submerged oil residues trapped within the near-shore ecosystem.