Developed unique way to fingerprint oil and assess how it changes over time
Years after the 2010 Deepwater Horizon Oil spill, oil continues to wash ashore as oil-soaked "sand patties," persists in salt marshes abutting the Gulf of Mexico, and questions remain about how much oil has been deposited on the seafloor.
Researchers used comprehensive two-dimensional gas chromatography (GCxGC) in their oil spill forensics to measure levels of degradation in biomarkers. THe biomarkers here are shown inside the dotted line.
Credit: Christoph Aeppli, Bigelow Laboratory for Ocean Sciences
Scientists from Woods Hole Oceanographic Institution and Bigelow Laboratory for Ocean Sciences have developed a unique way to fingerprint oil, even after most of it has degraded, and to assess how it changes over time. Researchers refined methods typically used to identify the source of oil spills and adapted them for application on a longer time frame to successfully identify Macondo Well oil, years after the spill.
"We were looking at two questions: how could we identify the oil on shore, now four years after the spill, and how the oil from the spill was weathering over time," explained Christoph Aeppli, Senior Research Scientist at Bigelow Laboratory for Ocean Sciences in East Boothbay, Maine, and lead author of the study reported in Environmental Science & Technology. Aeppli worked with his then-colleagues at Woods Hole Oceanographic Institution, and University of California, Santa Barbara on the investigation and report.
Researchers used comprehensive two-dimensional gas chromatography (GCxGC) in their oil spill forensics to measure levels of degradation in biomarkers. Biomarkers are molecular fossils. Each reservoir has specific amounts of different biomarkers, so oil biomarkers serve as identifiers much like human fingerprints.
Biomarkers are usually recalcitrant in reservoirs, but when exposed for a long time to the environment, some are altered due to natural processes. Oil consists of tens of thousands of compounds, and many of them can be degraded by bacteria or broken down by sunlight. This research was designed to determine the resiliency of specific biomarkers and to see how they held up when exposed to environmental conditions on shore.
"We found that some biomarkers—homohopanes and triaromoatic steroids (TAS), specifically – degraded within a few years following the Deepwater Horizon spill," said Chris Reddy, a scientist at Woods Hole Oceanographic Institution and co-author of the paper. "These biomarkers are not as resilient as once thought and they may provide a future window into determining how much, and how quickly, these oil components may linger in the environment when exposed to air, sunlight, and the elements."
Researchers sought to determine the specific source of the biomarkers degradation. Through analysis of oil-soaked "sand patties" collected along the Gulf shore over a 28-month period, they found that most biomarker compounds were recalcitrant and could be used to identify DWH oil. Some biomarkers, however, degraded. "This knowledge is helping us improve our oil spill forensics. It is providing a foundation for better, longer-term identification techniques that account for exposure of oil to wind, waves, sunlight, and microbial degradation over long times," added Aeppli.
Aeppli, Reddy and colleague Dave Valentine from UC Santa Barbara will apply this new oil fingerprinting technique to process tens of thousands of samples collected shortly after the DWH spill.
The Woods Hole Oceanographic Institution is a private, non-profit organization on Cape Cod, Mass., dedicated to marine research, engineering, and higher education. Established in 1930 on a recommendation from the National Academy of Sciences, its primary mission is to understand the ocean and its interaction with the Earth as a whole, and to communicate a basic understanding of the ocean's role in the changing global environment. For more information, please visit http://www.whoi.edu.
Bigelow Laboratory for Ocean Sciences conducts research ranging from microbial oceanography to large-scale ocean processes that affect the global environment. Recognized as a leader in Maine's emerging innovation economy, the Laboratory's research, education, and technology transfer programs are spurring significant economic growth in the state.
Darlene Crist | Eurek Alert!
Conservationists are sounding the alarm: parrots much more threatened than assumed
15.09.2017 | Justus-Liebig-Universität Gießen
A new indicator for marine ecosystem changes: the diatom/dinoflagellate index
21.08.2017 | Leibniz-Institut für Ostseeforschung Warnemünde
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
22.09.2017 | Life Sciences
22.09.2017 | Medical Engineering
22.09.2017 | Physics and Astronomy