Biological Effects of Dispersants and Dispersed Oil in Surface and Deep Ocean Species

Beginning with the use of industrial-strength detergents, dispersing agents have been employed in spill response for decades. The Corexit series of agents in common use today generally consist of non-ionic and/or anionic surfactants in a solvent base designed to enhance miscibility under varying temperature and salinity conditions; cationic surfactants tend to be too toxic for use. While dispersants generally serve to decrease the interfacial surface tension of oil, thus facilitating its weathering under low-energy conditions, their surface-active nature also causes their interaction with cell surfaces – those of single-celled organisms as well as the gills of vertebrates and invertebrates

PAH- and PCB-induced Alterations of Protein Tyrosine Kinase and Cytokine Gene Transcription in Harbor Seal (Phoca Vitulina) PBMC

Mechanisms underlying in vitro immunomodulatory effects of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) were investigated in harbor seal peripheral leukocytes, via real-time PCR. We examined the relative genetic expression of the protein tyrosine kinases (PTKs) Fyn and Itk, which play a critical role in T cell activation, and IL-2, a cytokine of central importance in initiating adaptive immune responses. IL-1, the macrophage-derived pro-inflammatory cytokine of innate immunity, was also included as a measure of macrophage function. Harbor seal PBMC were exposed to the prototypic immunotoxic PAH benzo[a]pyrene (BaP), 3,3',4,4',5,5'-hexachlorobiphenyl (CB-169), a model immunotoxic PCB, or DMSO (vehicle control). Exposure of Con A-stimulated harbor seal PBMC to both BaP and CB-169 produced significantly altered expression in all four targets relative to vehicle controls. The PTKs Fyn and Itk were both up-regulated following exposure to BaP and CB-169. In contrast, transcripts for IL-2 and IL-1 were decreased relative to controls by both treatments. Our findings are consistent with those of previous researchers working with human and rodent systems and support a hypothesis of contaminant-altered lymphocyte function mediated (at least in part) by disruption of T cell receptor (TCR) signaling and cytokine production

Proliferative Responses of Harbor Seal (Phoca vitulina) T Lymphocytes to Model Marine Pollutants

In recent years, population declines related to viral outbreaks in marine mammals have been associated with polluted coastal waters and high tissue concentrations of certain persistent, lipophilic contaminants. Such observations suggest a contributing role of contaminant-induced suppression of cell-mediated immunity leading to decreased host resistance. Here, we assessed the effects of the prototypic polycyclic aromatic hydrocarbon (PAH), benzo[a]pyrene (B[a]P), and two polychlorinated biphenyls (PCBs), CB-156 and CB-80, on the T-cell proliferative response to mitogen in harbor seal peripheral lymphocytes. Despite the variability associated with our samples from free-ranging harbor seals, we observed a clear suppressive effect of B[a]P (10 uM) exposure on T cell mitogenesis. Exposures to 10 uM CB-156 and CB-80, and 1.0 and 0.1 uM B[a]P, did not produce significant depression in lymphoproliferation. Exposure to the model PAH at 10 uM resulted in a 61% (range 34-97%) average reduction in lymphoproliferation. We were able to rule out a direct cytotoxic effect of B[a]P, indicating that observed effects were due to altered T cell function. Based on our in vitro results, we hypothesize that extensive accumulation of PAH by top-trophic-level marine mammals could alter T cell activation in vivo and impaired cell-mediated immunity against viral pathogens

Proteomic identification, cDNA cloning and enzymatic activity of glutathione S-transferases from the generalist marine gastropod, Cyphoma gibbosum

Author Posting. © Elsevier B.V., 2008. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Archives of Biochemistry and Biophysics 478 (2008): 7-17, doi:10.1016/j.abb.2008.07.007.Glutathione S-transferases (GST) were characterized from the digestive gland of Cyphoma gibbosum (Mollusca; Gastropoda), to investigate the possible role of these detoxification enzymes in conferring resistance to allelochemicals present in its gorgonian coral diet. We identified the collection of expressed cytosolic Cyphoma GST classes using a proteomic approach involving affinity chromatography, HPLC and nanospray liquid chromatography-tandem mass spectrometry (LC-MS/MS). Two major GST subunits were identified as putative mu-class GSTs; while one minor GST subunit was identified as a putative theta-class GST, apparently the first theta-class GST identified from a mollusc. Two Cyphoma GST cDNAs (CgGSTM1 and CgGSTM2) were isolated by RT-PCR using primers derived from peptide sequences. Phylogenetic analyses established both cDNAs as mu-class GSTs and revealed a mollusc-specific subclass of the GST-mu clade. These results provide new insights into metazoan GST diversity and the biochemical mechanisms used by marine organisms to cope with their chemically defended prey.Support was provided by the WHOI-Cole Ocean Ventures Fund (KEW), the WHOI Ocean Life Institute (KEW and MEH), a grant from Walter A. and Hope Noyes Smith (MEH), the National Science Foundation Graduate Research Fellowship (KEW), and by the National Institutes of Health (P42-ES007381 and R01-ES015912 to JVG)

A Tale of Two Spills: Novel Science and Policy Implications of an Emerging New Oil Spill Model

The 2010 Deepwater Horizon oil release posed the challenges of two types of spill: a familiar spill characterized by buoyant oil, fouling and killing organisms at the sea surface and eventually grounding on and damaging sensitive shoreline habitats, and a novel deepwater spill involving many unknowns. The subsurface retention of oil as finely dispersed droplets and emulsions, wellhead injection of dispersants, and deepwater retention of plumes of natural gas undergoing rapid microbial degradation were unprecedented and demanded the development of a new model for deepwater well blowouts that includes subsurface consequences. Existing governmental programs and policies had not anticipated this new theater of impacts, which thereby challenged decisionmaking on the spill response, on the assessment of natural resource damages, on the preparation for litigation to achieve compensation for public trust losses, and on restoration. Modification of laws and policies designed to protect and restore ocean resources is needed in order to accommodate oil drilling in the deep sea and other frontiers.Keywords: Ecosystem, Petroleum, Deep water horizon, Gulf of Mexico, BlowoutKeywords: Ecosystem, Petroleum, Deep water horizon, Gulf of Mexico, Blowou

Sublethal Toxic Effects of Water Pollution on Red Abalone

Though difficult to quantify, chemicals in agricultural and urban runoff are contributing to population declines of commercially valuable marine species. Although these pollutants may not be immediately lethal to marine organisms, they can impair key biological processes, hindering reproduction and causing early death

Electronic Supporting Information 2 - Environmental Fate and Aquatic Risk Assessment of Oxyfluorfen in California Rice Fields

This resource serves as Electronic Supporting Information for the Ph.D. dissertation chapter titled 'Fate and Aquatic Risk of Oxyfluorfen Under Simulated California Rice Field Conditions' prepared by David J. Bonnar.Descriptions of file contents:• PFAM Risk Assessment Summary.xlsx -Presents summary results tables for all scenarios.• Results for specific application scenarios are provided in the respective scenario folders and include the following files:PFAMtransferfile.xxx - A parameter transfer file generated and used by PFAM during each model run.[Scenario].PFA - The PFAM input file for the scenario. Fully parametrizes the model for the scenario when retrieved by PFAM.[Scenario]_paddy.raw - Daily output data from PFAM[Scenario]_AncillaryInfo.txt - A summary of the effective average dissipation processes for the PFAM simulation and conversion factors for benthic concentrations[Scenario]_paddy_1-in-10.txt - A summary of the 1-in-10 year concentrations for the paddy.[Scenario]_paddy_DailyRecord.txt - Provides daily records of paddy characteristics, including depth, release volumes, and water & benthic concentrations[Scenario]_ResultsSummary.xlsx - A summary of PFAM and aquatic risk assessment results for the scenario and a full description of scenario parametrization.• Supplementary Scenarios - Simulations of 30 day water holding scenarios (S-30, B-30, D-30) without degradation. File contents follow same format as the application scenarios described above.</p

Electronic Supporting Information 1 - Predicting Air-Water Partitioning of Oxyfluorfen Under California Rice Field Conditions

This resource serves as Electronic Supporting Information for the Ph.D. dissertation chapter titled 'Predicting Air-Water Partitioning of Oxyfluorfen Under California Rice Field Conditions: An Approach for Broader Application' prepared by David J. Bonnar.Electronic Supporting Information 1.xlsxExcel spreadsheet containing fully parametrized models, data, and results of the study.</p

Pharmacokinetics and Efficacy of Oxytetracycline in RLP-infected Abalone

Sea Grant research has led to the development of a cure for an abalone wasting disease that destroyed about $1.5-million worth of farmed abalone product at two California farms during the1997–98 El Niño. The antibiotic therapy is now being used to help in the restoration of endangered wild white abalone on the U.S. West Coast