bp oil spill: one year later what did we learn and where
TRANSCRIPT
BP Oil Spill: One Year LaterWhat Did We Learn and Where Are We Now?
Edward B. Overton, PhDProfessor Emeritus
Department of Environmental ScienceLouisiana State University
Baton Rouge, LA
Mechanisms to causeEnvironmental Impactsfrom Oil Spills
•Toxicity•Smothering•Oxygen depletion•(production of biomass/incorporation into food web)•Some remedial activities
Toxic & StickyFloating
StickyFloatingSinking?
Tarball ,Tarmats
Surface Oil Weathering
GunkyFloatingSinking
Days Weeks MonthsThe Effects of Weathering on Spilled Oil
Loss of Light EndVOCs due to evaporationand dissolution
Saturates and AromaticsDegraded by bacteria
Residue Asphaltene
Harm = {Toxicity + Dose} + Route of Exposure
amount Oil water emulsification
Photos Source: OceanFutureSociety
Surface Weathered Oil
Just below Surface Slick
Fresh
Boswell
Sediment
C17/Pr C18/Ph C2 Naphthalenes
Toxic & StickyFloating
StickyFloatingSinking?
Tarball /Tarmats
Surface Oil Weathering
GunkyFloatingSinking
Days Weeks MonthsThe Effects of Weathering on Spilled Oil
Harm = {Toxicity + Dose} + Route of Exposure
Quantitative Analysis of oil in the environment is problematic because of oil’s heterogeneous distribution
Fresh
Weathered
Green regrowth on oiled areas
Green regrowth on oiled areas
no regrowth on oiled areas
Green regrowth on oiled areas
no regrowth on oiled areas
no regrowth on oiled areas
Heavily Weathered Oiled Marsh Sediment
Bay JimmyMay 15, 2011
Detection of subsurface oil1. near surface and at depth2. gaseous markers of oil3. buried or tar mats4. sunken oil?
Identification of oil1. weathering2. fingerprinting3. ID petrogenic material
Dispersant/ISB/Skimmer Monitoring1. effectiveness at depth and from surface application2. oil concentrations in water column3. dispersed oil degradation4. dispersant detection in water column
Worker and general population safety (direct exposures)1. at ground zero2. cleanup sites3. population centers at risk from exposures
Seafood safety1. detection of contamination2. is the seafood safe to eat from PAH concentration perspective
AnalyticalContributions To Oil SpillResponses
Analytical Techniques for Oil Spills (organics): • GC (gas chromatography): TPH• GCMS (gc mass spectrometry): TPAH, fingerprints, biomarkers,
dispersant indicators• GCxGC TOFMS: more selective GCMS • HRMS (high resolution MS): petronomics?• GCMSMS: a bit more selective GCMS for seafood analysis• LCMSMS (liquid chromatography MSMS): a bit faster PAHs in
seafood• Taste and Smell: petroleum contamination in seafood• LCHRMS: DOSS in deep water samples• Cyclotron X-ray fluorescence: sulfur speciations• FTIR• UV• UV Fluorescence