Transcript Dispersed Petroleum Toxicity in Ice

Food Web Discussion
• Valuable Ecosystem Components for Beaufort
and Chukchi Seas
• Effects of circulation on food web and VECs
Bowhead
Whales
Orca
Beluga
Arctic Cod
Other Pelagics
Neuston
Ringed
Seal
Polar
Bear
Zooplankton
Herring
Sandlance
Smelt
Phytoplankton
Anadromus
Fish
Microzooplankton
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Fate and Transport Discussion
How does fate impact dispersed oil evaluations?
Considerations
• Dispersed oil constituents present
• Time period for constituents
• Pelagic species affected
• Biodegradation potential
• Rate of degradation vs toxicity
Test Species Discussion
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Arctic species (or surrogate)
Important link in the pelagic food web
Community approach
Several species from different phyla
Life stage
Sensitivity to dispersed petroleum
Existing methodology
Amenable to handling and arctic test conditions
Readily available
Appropriate endpoints
Performance standards
Potential Test Species
Species
Arctic cod
Herring juv.
Capelin juv.
Saffron cod
Arctic cisco juveniles
Dolly varden subadults
Pink salmon
Sculpin
Methods
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Sensitivity
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Species
Methods Sensitivity
C. finmarchicus
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C. hyperborialis
C. glacialis
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0
Tanner crab
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Mysid
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Gammarus spp.
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Onisimus littoralis
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Clams
Sea urchins
Phytoplankton
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Test Method Discussion
Testing
Temperature (5 deg) and Salinity (28 – 30)
Exposure Type and Duration (SPIKE)
Duration remains an issue
Oil-Dispersant Preparations
WAF and CE-WAF (25% Vortex)
Variable Loading vs Serial Dilution
Mixing Energy, Duration, Light (no UV)
Physical Conditions (same as test)
Oil:dispersant (20:1)and Oil:water Ratio (200:1)
Droplets (try to measure?)
Weathering (No)
Chemical Analyses (broad suite)
Testing Strategy & Process Discussion
• Can the results of the laboratory studies confidently
predict what will happen in the field?
– Which compartments to address
– Role of Transport Modeling
– Exposure and Duration
– Analytical Chemistry
– Using Arctic Appropriate Testing Conditions
– Interaction of biodegradation and toxicity
• What criteria should be used to assess the data?
• How much data is required for assessment?