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OSAT - Summary Report for Sub-Sea and Sub-Surface Oil and Dispersant Detection: Ecotoxicity Addendum

The purpose of this report addendum is to provide the Federal OnScene Coordinator (FOSC) for the Deepwater Horizon MC252 Spill of National Significance with information on the toxicity of released oil and dispersant to representative water column and sedimentdwelling organisms. This information is intended to inform the FOSC regardingtransition of offshore activities from the emergency response phase to the long term recovery and restoration phase.

Collections of water and sediment samples for ecotoxicity testing and chemical anlysis were conducted by U.S. Environmental Protection Agency, U.S. Geological Survey and BP (the responsible party) during the Response to the Deepwater Horizon MC252 Spill of National Significance. This report provides an assessment of the distribution of the samples and results of ecotoxicity tests and concurrent chemical analyses of oil related compounds and markers of dispersants.

Mapping and analytical chemistry results used in this report and throughout the Deepwater Horizon Spill Response are available in the on-line web mapping Emergency Response Management Application web site:  Select the interactive map option, click through the information pop-up page, and select the Zoom tab on the upper right hand portion of the main page to access bookmarked figures from the OSAT report. 


    Ecotoxicity Addendum

    Ecotoxicity Appendices

    Ecotoxicity Master Database


Geoplatform – Mapping

Geoplatform provides a geospatial representation of the data used in the OSAT report.  Along with the mapping, attached to the layer are other types of media including report maps and spreadsheets for chemistry data used to support the analyses.  The name of the links below correspond to the analyses and the data sets that were used for each.

Nearshore Toxicity Sample Locations

Pre-Impact Toxicity

Nearshore Toxicity Samples Collected After 3 August 2010

Exceedances of EPA's Chronic Aquatic Benchmark for PAHs After 3 August 2010

MC252 Oil Fingerprint Results for Nearshore Samples Collected After 3 August 2010

Sediment Toxicity Samples Collected After 3 August 2010

Water Toxicity Samples Collected After 3 August 2010

Resample of Pre-Impact Toxicity After 3 August 2010

Dispersant Samples Collected After 3 August 2010

Integrated Evaluation of Data After 3 August 2010 - Significant Effects