Recalcitrance and degradation of petroleum biomarkers upon abiotic and biotic natural weathering of Deepwater Horizon oil.

Petroleum biomarkers such as hopanoids, steranes, and triaromatic steroids (TAS) are commonly used to investigate the source and fate of petroleum hydrocarbons in the environment based on the premise that these compounds are resistant to biotic and abiotic degradation. To test the validity of this premise in the context of the Deepwater Horizon disaster, we investigated changes to these biomarkers as induced by natural weathering of crude oil discharged from the Macondo Well (MW). For surface slicks collected from May to June in 2010, and other oiled samples collected on beaches in the northern Gulf of Mexico from July 2010 until August 2012, hopanoids with up to 31 carbons as well as steranes and diasteranes were not systematically affected by weathering processes. In contrast, TAS and C32- to C35-homohopanes were depleted in all samples relative to 17α(H),21β(H)-hopane (C30-hopane). Compared to MW oil, C35-homohopanes and TAS were depleted by 18 ± 10% and 36 ± 20%, respectively, in surface slicks collected from May to June 2010, and by 37 ± 9% and 67 ± 10%, respectively, in samples collected along beaches from April 2011 through August 2012. Based on patterns of relative losses of individual compounds, we hypothesize biodegradation and photooxidation as main degradation processes for homohopanes and TAS, respectively. This study highlights that (i) TAS and homohopanes can be degraded within several years following an oil spill, (ii) the use of homohopanes and TAS for oil spill forensics must account for degradation, and (iii) these compounds provide a window to parse biodegradation and photooxidation during advanced stages of oil weathering.

[1]  Thomas J McDonald,et al.  Aerobic biodegradation of hopanes and other biomarkers by crude oil-degrading enrichment cultures. , 2002, Environmental science & technology.

[2]  M. Fingas,et al.  Chemical Characterization of Crude Oil Residues from an Arctic Beach by GC/MS and GC/FID. , 1995, Environmental science & technology.

[3]  Stephen D. Emsbo-Mattingly,et al.  Advantages of quantitative chemical fingerprinting in oil spill source identification , 2007 .

[4]  P. Albrecht,et al.  Abiotic oxidation of petroleum bitumens under natural conditions. , 2000 .

[5]  Karin L. Lemkau,et al.  Floating oil-covered debris from Deepwater Horizon: identification and application , 2012 .

[6]  Z. Sofer,et al.  Source Rock in the Lower Tertiary and Cretaceous, Deep-Water Gulf of Mexico , 1994 .

[7]  T. Clement,et al.  Chemical fingerprinting of petroleum biomarkers in Deepwater Horizon oil spill samples collected from Alabama shoreline. , 2013, Marine pollution bulletin.

[8]  Cortis K. Cooper,et al.  Natural seepage of crude oil into the marine environment , 2001 .

[9]  R. Prince,et al.  17.alpha.(H)-21.beta.(H)-hopane as a conserved internal marker for estimating the biodegradation of crude oil. , 1994, Environmental science & technology.

[10]  J Samuel Arey,et al.  Disentangling oil weathering using GC x GC. 1. chromatogram analysis. , 2007, Environmental science & technology.

[11]  J. Laseter,et al.  Dye-sensitized photooxidation of phenanthrene. , 1974, Biochemical and biophysical research communications.

[12]  Moonkoo Kim,et al.  Compositional Changes of Aromatic Steroid Hydrocarbons in Naturally Weathered Oil Residues in the Egyptian Western Desert , 2002 .

[13]  Per S. Daling,et al.  Emerging CEN methodology for oil spill identification , 2007 .

[14]  Catherine A. Carmichael,et al.  Oxygenated weathering products of Deepwater Horizon oil come from surprising precursors. , 2013, Marine pollution bulletin.

[15]  Christoph Aeppli,et al.  Oil weathering after the Deepwater Horizon disaster led to the formation of oxygenated residues. , 2012, Environmental science & technology.

[16]  R. Nelson,et al.  Separation of 18α(H)-, 18β(H)-oleanane and lupane by comprehensive two-dimensional gas chromatography. , 2011, Journal of chromatography. A.

[17]  B. Okeke,et al.  Level and degradation of Deepwater Horizon spilled oil in coastal marsh sediments and pore-water. , 2012, Environmental science & technology.

[18]  K. J. Mccarthy,et al.  A Strategy and Methodology for Defensibly Correlating Spilled Oil to Source Candidates , 2001 .

[19]  P. Doumenq,et al.  Long term evolution of petroleum biomarkers in mangrove soil (Guadeloupe) , 1997 .

[20]  L. Hickey,et al.  The Molecular Fossil Record of Oleanane and Its Relation to Angiosperms , 1994, Science.

[21]  C. Reddy,et al.  Photochemical degradation of polycyclic aromatic hydrocarbons in oil films. , 2008, Environmental science & technology.

[22]  Roger C. Prince,et al.  Photooxidation of crude oils , 1998 .

[23]  M. Beyer,et al.  The chitinase system ofStreptomyces sp. ATCC 11238 and its significance for fungal cell wall degradation , 1985, Applied Microbiology and Biotechnology.

[24]  Oliver C. Mullins,et al.  Analysis of petroleum compositional similarity using multiway principal components analysis (MPCA) with comprehensive two-dimensional gas chromatographic data. , 2011, Journal of chromatography. A.

[25]  M. Suidan,et al.  Use of hopane as a conservative biomarker for monitoring the bioremediation effectiveness of crude oil contaminating a sandy beach , 1997, Journal of Industrial Microbiology and Biotechnology.

[26]  M Fingas,et al.  Study of 22-Year-Old Arrow Oil Samples Using Biomarker Compounds by GC/MS. , 1994, Environmental science & technology.

[27]  G. Douglas,et al.  Laboratory and field verification of a method to estimate the extent of petroleum biodegradation in soil. , 2012, Environmental science & technology.

[28]  B. Raghuraman,et al.  Compound class oil fingerprinting techniques using comprehensive two-dimensional gas chromatography (GC×GC) , 2010 .

[29]  Mace G Barron,et al.  Comparative toxicity of eight oil dispersants, Louisiana sweet crude oil (LSC), and chemically dispersed LSC to two aquatic test species , 2011, Environmental toxicology and chemistry.

[30]  R. Nelson,et al.  Comparison of GC–MS, GC–MRM-MS, and GC × GC to characterise higher plant biomarkers in Tertiary oils and rock extracts , 2012 .

[31]  Pen-Yuan Hsing,et al.  Impact of the Deepwater Horizon oil spill on a deep-water coral community in the Gulf of Mexico , 2012, Proceedings of the National Academy of Sciences.

[32]  M. Fingas,et al.  Long-term fate and persistence of the spilled metula oil in a marine salt marsh environment degradation of petroleum biomarkers. , 2001, Journal of chromatography. A.

[33]  T. McDonald,et al.  Aerobic biodegradation of hopanes and norhopanes in Venezuelan crude oils , 2001 .

[34]  Christoph Aeppli,et al.  Assessment of photochemical processes in marine oil spill fingerprinting. , 2014, Marine pollution bulletin.

[35]  D. Valentine,et al.  Recurrent oil sheens at the deepwater horizon disaster site fingerprinted with synthetic hydrocarbon drilling fluids. , 2013, Environmental science & technology.

[36]  Simone Meinardi,et al.  Chemical data quantify Deepwater Horizon hydrocarbon flow rate and environmental distribution , 2012, Proceedings of the National Academy of Sciences.

[37]  R. Prince,et al.  Weathering of an Arctic oil spill over 20 years: the BIOS experiment revisited. Baffin Island Oil Spill. , 2002, Marine pollution bulletin.

[38]  Karin L. Lemkau,et al.  Composition and fate of gas and oil released to the water column during the Deepwater Horizon oil spill , 2011, Proceedings of the National Academy of Sciences.

[39]  Lloyd M. Wenger,et al.  Multiple Controls on Petroleum Biodegradation and Impact on Oil Quality , 2002 .

[40]  Catherine A. Carmichael,et al.  Resolving biodegradation patterns of persistent saturated hydrocarbons in weathered oil samples from the Deepwater Horizon disaster. , 2014, Environmental science & technology.

[41]  C. Reddy,et al.  GC × GC--A New Analytical Tool For Environmental Forensics , 2002 .

[42]  Glenn S. Frysinger,et al.  Oil Spill Source Identification by Comprehensive Two-Dimensional Gas Chromatography , 1999 .