Characterization of subsurface polycyclic aromatic hydrocarbons at the Deepwater Horizon site

TitleCharacterization of subsurface polycyclic aromatic hydrocarbons at the Deepwater Horizon site
Publication TypeJournal Article
Year of Publication2010
AuthorsDiercks AR, Highsmith RC, Asper VL, Joung DJ, Zhou ZZ, Guo LD, Shiller AM, Joye SB, Teske AP, Guinasso N, Wade TL, Lohrenz SE
JournalGeophysical Research Letters
Date PublishedOct
ISBN Number0094-8276
Accession NumberWOS:000283545300005
KeywordsDeepwater Horizon Oil Spill, Oil and Gas Degradation
AbstractHere, we report the initial observations of distributions of polycyclic aromatic hydrocarbons (PAH) in subsurface waters near the Deepwater Horizon oil well site (also referred to as the Macondo, Mississippi Canyon Block 252 or MC252 well). Profiles of in situ fluorescence and beam attenuation conducted during 9-16 May 2010 were characterized by distinct peaks at depths greater than 1000 m, with highest intensities close to the wellhead and decreasing intensities with increasing distance from the wellhead. Gas chromatography/mass spectrometry (GC/MS) analyses of water samples coinciding with the deep fluorescence and beam attenuation anomalies confirmed the presence of polycyclic aromatic hydrocarbons (PAH) at concentrations reaching 189 μg L−1 (ppb). Subsurface exposure to PAH at levels considered to be toxic to marine organisms would have occurred in discrete depth layers between 1000 and 1400 m in the region southwest of the wellhead site and extending at least as far as 13 km.