Evaluating the effects of Oil Spill Eater II on Oil Degradation in Alaskan Marine Environments
Evaluating the effects of Oil Spill Eater II on Oil Degradation in Alaskan Marine EnvironmentsMary Beth Leigh, University of Alaska Fairbanks
Scope of Work:
The Alaskan Arctic and sub-Arctic marine environments are subject to growing risks of crude oil and marine fuel spills due to increased ship traffic and the potential for offshore oil and gas development. It is important for oil spill preparedness planning to be based upon a sound scientific understanding of the efficacy of spill response products and their potential environmental impacts to marine ecology. Yet, the fate and effects of several products on the Environmental Protection Agency’s National Contingency Plan (NCP) product schedule have not been evaluated thoroughly for Alaskan waters. Chemical dispersants are receiving increased research attention, but there has not yet been a thorough scientific evaluation of the heavily marketed bioremediation product, Oil Spill Eater II (OSEII) in any marine environment, including in Alaska. OSEII’s formulation is not publicly known, but it reportedly contains mineral nutrients, amylase and protease enzymes, molasses as a carbon source, and an oleophilic surfactant. Although OSEII is listed on the NCP Schedule as an enzymatic additive, the enzymes it reportedly contains (protease and amylase) are not capable of directly catalyzing petroleum biodegradation. OSEII’s diverse ingredients suggest multiple other possible modes of action, such as chemical dispersion, biostimulation through nutrient addition and/or through additions of labile carbon sources. Rigorous scientific examination of the effectiveness and mode(s) of action of OSEII for biodegrading and detoxifying oil, as well as its impacts on microbial ecology of marine ecosystems, is warranted in order to ensure that this product is effective, properly classified on the NCP Schedule, and that its potential effects are understood prior to field application.
The aims of this proposed project are to 1) evaluate the effectiveness of OSEII on crude oil and marine diesel degradation and detoxification in Arctic and sub-Arctic seawater, 2) determine its mode(s) of action, 3) compare its efficacy to that of chemical dispersants (Corexit 9500A), and 4) to assess effects on indigenous microbial communities. The effects of OSEII on crude oil and diesel biodegradation and detoxification will be determined using laboratory incubation studies with freshly collected seawater containing indigenous microorganisms from the Arctic (open water and under-ice) and sub-Arctic(open water) marine environments in Alaska. The potential for OSEII to act as a dispersant will also be investigated using EPA dispersant effectiveness test methods. Additional treatments will isolate and examine the roles of nutrients, molasses, and enzyme additives in petroleum degradation. The effects of OSEII on indigenous microbial communities, including oil-degraders and degradation genes, will be examined using advanced molecular methods (16S rRNA sequencing, metatranscriptomics, qPCR). This team has experience investigating oil biodegradation in Arctic waters, assessing the fate and effects of oil spill response chemicals (e. g. , Corexit 9500A), and in applying advanced molecular microbiological tools to these questions. The proposed work aligns with OSRI’s mission to support scientific evaluations of the potential effectiveness and impacts of oil spill response methods, including additives on the U. S. EPA NCP Schedule. Results will be communicated through conference presentations, peer-reviewed scientific publications, and through direct communications with OSRI, the Alaska Department of Environmental Conservation, and other agencies and stakeholders.