Ann L. Miracle

DEVELOPMENT AND VALIDATION OF A 2,000-GENE MICROARRAY FOR THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

Gene microarrays provide the field of ecotoxicology new tools to identify mechanisms of action of chemicals and chemical mixtures. Herein we describe the development and application of a 2,000-gene oligonucleotide microarray for the fathead minnow Pimephales promelas, a species commonly used in ecological risk assessments in North America. The microarrays were developed from various cDNA and subtraction libraries that we constructed. Consistency and reproducibility of the microarrays were documented by examining multiple technical replicates. To test application of the fathead minnow microarrays, gene expression profiles of fish exposed to 17beta-estradiol, a well-characterized estrogen receptor (ER) agonist, were examined. For these experiments, adult male fathead minnows were exposed for 24 h to waterborne 17beta-estradiol (40 or 100 ng/L) in a flow-through system, and gene expression in liver samples was characterized. Seventy-one genes were identified as differentially regulated by estradiol exposure. Examination of the gene ontology designations of these genes revealed patterns consistent with estradiols expected mechanisms of action and also provided novel insights as to molecular effects of the estrogen. Our studies indicate the feasibility and utility of microarrays as a basis for understanding biological responses to chemical exposure in a model ecotoxicology test species.

Genomics in regulatory ecotoxicology : applications and challenges

Contents Toxicogenomics in Ecological Risk Assessments: Regulatory Context, Technical Background, and Workshop Overview, G.T. Ankley, A.L. Miracle, and E.J. Perkins Application of Genomics to Screening, S.W. Kennedy, S. Euling, D.B. Huggett, W. De Coen, J.R. Snape, T.R. Zacharewski, and J. Kanno Application of Genomics to Tiered Testing, C.R. Tyler, A.L. Filby, T. Iguchi, V.J. Kramer, D.G.J. Larsson, G. van Aggelen, K. van Leeuwen, M.R. Viant, and D.E. Tillitt Application of Genomics to Regulatory Ecological Risk Assessments for Pesticides, S.J. Degitz, R.A. Hoke, S. Bradbury, R. Brennan, L. Ferguson, R. Klaper, L. Orban, D. Spurgeon, and S. Tilton Application of Genomics to Assessment of the Ecological Risk of Mixtures, E.J. Perkins, N. Denslow, J.K. Chipman, P.D. Guiney, J.R. Oris, H. Poynton, P.Y. Robidoux, R. Scroggins, and G. Van Der Kraak Applications of Genomic Technologies to Ecological Risk Assessment at Remediation / Restoration Sites, A.L. Miracle, C.W. Evans, E.A. Ferguson, B. Greenberg, P. Kille, A.R. Schaeffner, M. Sprenger, R. van Aerle, and D.J. Versteeg Toxicogenomics in Ecological Risk Assessments: A Prospectus, G.P. Daston, A.L. Miracle, E.J. Perkins, and G.T. Ankley

Scientific Opportunities for Monitoring at Environmental Remediation Sites (SOMERS): Integrated Systems-Based Approaches to Monitoring

Through an inter-disciplinary effort, DOE is addressing a need to advance monitoring approaches from sole reliance on cost- and labor-intensive point-source monitoring to integrated systems-based approaches such as flux-based approaches and the use of early indicator parameters. Key objectives include identifying current scientific, technical and implementation opportunities and challenges, prioritizing science and technology strategies to meet current needs within the DOE complex for the most challenging environments, and developing an integrated and risk-informed monitoring framework.

Growth inhibition and stimulation of Shewanella oneidensis MR-1 by surfactants and calcium polysulfide

Foam delivery technology (FDT) uses surfactant based foam to immobilize subsurface contaminants in situ. Where traditional approaches are impractical, FDT has the potential to overcome many of the technical challenges facing the remediation of contaminated deep vadose zone environments. However, little is known about the effects these reactive chemicals may have on microorganisms inhabiting the contaminated subsurface. In addition, there are currently no standard assays to assess microbial responses to subsurface remedial treatments while these agents are under development. The objective of this study was to develop a rapid laboratory assay to assess the potential growth inhibition and/or stimulation of microorganisms following exposure to candidate FDT components. Calcium polysulfide (CPS) and several surfactants (i.e. sodium laureth sulfate (SLES), sodium dodecyl sulfate (SDS), cocamidopropyl betaine (CAPB) and NINOL40-CO) have diverse chemistries and are candidate components of FDT. Shewanella oneidensis MR-1 cultures were exposed to a range of concentrations of these chemicals to determine the minimum bactericidal concentration (MBC) and the growth and viability potential of these components. Concentrations of SDS higher than 700 μM were toxic to S. oneidensis MR-1 growth over the course of four days of exposure. The relative acute toxicity order for these compounds was SDS >> CPS >> NINOL 40-CO>SLES≥CAPB. Dose dependent growth decreases (20-100mM) were observed in the CAPB and SLES treated cultures and both CPS and NINOL 40-CO were toxic at all concentrations tested (1.45-7.25 mM CPS). Both SLES (20-100mM) and SDS at lower concentrations (20-500 μM) were stimulatory to S. oneidensis MR-1 indicating a capacity to be used as a carbon source. These studies also identified potentially key component characteristics, such as precipitate formation and oxygen availability, which may prove valuable in assessing the response of subsurface microorganisms. This benchtop system provides a capability to assess adverse microbial-remediation responses and contributes to the development of in situ remedial chemistries before they are deployed in the field.

Spillway-Induced Salmon Head Injury Triggers the Generation of Brain αII-Spectrin Breakdown Product Biomarkers Similar to Mammalian Traumatic Brain Injury

Recent advances in biomedical research have resulted in the development of specific biomarkers for diagnostic testing of disease condition or physiological risk. Of specific interest are αII-spectrin breakdown products (SBDPs), which are produced by proteolytic events in traumatic brain injury and have been used as biomarkers to predict the severity of injury in humans and other mammalian brain injury models. This study describes and demonstrates the successful use of antibody-based mammalian SBDP biomarkers to detect head injury in migrating juvenile Chinook salmon (Oncorhynchus tshawytscha) that have been injured during passage through high-energy hydraulic environments present in spillways under different operational configurations. Mortality and injury assessment techniques currently measure only near-term direct mortality and easily observable acute injury. Injury-based biomarkers may serve as a quantitative indicator of subacute physical injury and recovery, and aid hydropower operators in evaluation of safest passage configuration and operation actions for migrating juvenile salmonids. We describe a novel application of SBDP biomarkers for head injury for migrating salmon. To our knowledge, this is the first documented cross-over use of a human molecular biomarker in a wildlife and operational risk management scenario.