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Ecological Exposure Research Division Publications: 2005

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This page lists publication titles, citations and abstracts produced by NERL's Ecological Exposure Research Division for the year 2005, organized by Publication Type. Your search has returned 57 Matching Entries.

See also Ecological Exposure Research Division citations with abstracts: 1999,  2000,  2001,  2002,  2003,  2004,  2005,  2006,  2007,  2008,  2009

Technical Information Manager: Linda Ransick - (513) 569-7395 or ransick.linda@epa.gov

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Presented/Published
BOOK CHAPTER Detection of Temporal Trends in Ohio River Fish Assemblages Based on Lockchamber Surveys 09/01/2005
Thomas, J. A., E. B. Emery, AND F H. McCormick. Detection of Temporal Trends in Ohio River Fish Assemblages Based on Lockchamber Surveys. Chapter 22, John N. Rinne, Robert M. Hughes and Bob Calamusso (ed.), Historical Changes in Large River Fish Assemblages of the Americas. American Fisheries Society, Bethesda, MD, 45:431-450, (2005).
Abstract: The Ohio River Valley Water Sanitation Commission (ORSANCO), along with cooperating state and federal agencies, sampled fish assemblages from the lockchambers of Ohio River navigational dams from 1957 to 2001. To date, 377 lockchamber rotenone events have been conducted, resulting in the collection of nearly three million fishes, representing 116 taxa, including 7 hybrids, in 19 families. We observed significant temporal trends in Ohio River fish populations riverwide at the assemblage, guild, and species levels. Modified index of well-being (MIWB) scores and changes in guild structure indicated significantly (p<0.05) improving fish assemblages throughout the Ohio River. Quantile regression of the abundance of individual species by year revealed significant declines (p<0.05) in populations of several pollution-tolerant species (e.g., Ameiurus spp., Carassius auratus) with time, while some intolerant species (e.g., moxostoma macrolepidotum, Micropterus dolomieu, Hiodon tergisus) have increased in recent years. In all, 40 of the 116 taxa collected in the lockchamber surveys changed significantly over time. Sixteen species did not change. Sixty species could not be analyzed either because of incomplete data or insufficient abundance. Fish assemblage metrics that would be expected to decrease with improving conditions in the Ohio River (percent tolerant individuals, percent non-indigenous individuals, and percent detritivore individuals) also declined (p<0.05). These changes coincide with marked improvement of the water quality in the Ohio River over the last 50 years, particularly in the aftermath of the Clean Water Act (1972). Some species and metric responses may also be due to the replacement of the 50 wicket dams by the construction of 18 high-lift dams.

BOOK CHAPTER Approaches in Proteomics and Genomics for Eco-Toxicology 06/01/2005
DENSLOW, N. D., I. KNOEBL, AND P. LARKIN. Approaches in Proteomics and Genomics for Eco-Toxicology. , Chapter 3, T.P. Mommsen and T.W. Moon (ed.), Biochemistry and Molecular Biology of Fishes. Elsevier Science BV, Amsterdam, Netherlands, 6:85-116, (2005).
Abstract: A new area of scientific investigation, coined toxicogenomics, enables researchers to understand and study the interaction between the environment and inherited genetic characteristics. This understanding will be critical to fully appreciate the response of organisms to environmental stress and toxicants. The availability of whole genome sequences has ushered in this new field, for it is now possible to ask global questions about how physiological systems are perturbed and how metabolic pathways relate to each other. These questions will be important for assessing the risk of exposures to contaminants and for determining specific toxicant pathways and mechanisms of action. It is now clear that classes of chemicals, and perhaps even individual chemicals, will display their own "chemical signatures" both at the gene transcription and protein expression levels. Once these signatures are identified, it will be easier to determine the risk of exposures to populations of wildlife and even to humans.

JOURNAL Characterization of Microsatellite Loci in Schoenoplectus Americanus (Cyperaceae) 08/01/2005
BLUM, M. J., J. S. MCLACHLAN, C. J. SAUNDERS, AND J. D. HERRICK. Characterization of Microsatellite Loci in Schoenoplectus Americanus (Cyperaceae). MOLECULAR ECOLOGY NOTES. Blackwell Publishing Limited, Oxford, Uk, 5:661-663, (2005).
Abstract: Schoenoplectus americanus is a model organism for studying ecological and ecosystem responses of salt marsh plant communities to global climate change. Here we characterize 16 microsatellite loci in S. americanus to facilitate studies on the genetic basis of phenotypic responses to changing climate conditions such as elevated atmospheric carbon dioxide. Most loci also amplified in the morphologically similar sister species, S. pungens. Five loci exhibited species-specific alleles or distinct allelic size distributions that discriminate S. americanus from S. pungens.

JOURNAL Electrofishing in Boatable Rivers: Does Sampling Design Affect Bioassessment Metrics? 04/01/2005
Flotemersch, J E. AND K A. Blocksom. Electrofishing in Boatable Rivers: Does Sampling Design Affect Bioassessment Metrics? ENVIRONMENTAL MONITORING AND ASSESSMENT 102(1-3):263-283, (2005).
Abstract: The accurate bioassessment of boatable rivers using fish assemblage data requires that a representative sample of the assemblage be collected. In this study, data were collected using an electrofishing design that permitted comparisons of the effects of designs and distances on fish assemblage metrics. These fish and habitat data were collected from 60 boatable sites distributed among four rivers within the Ohio River Basin. Sites were classified a priori as either Run-of-the-River (ROR) or Restricted Flow (RF). At each site, one bank was electrofished to a distance of 40 times the wetted width, up to a maximum distance of 2000 m, and the opposite bank was electrofished to a distance of 1000 m. Fish were processed at up to 14 points during data collection. Data representing four different design options (i.e., 1000 and 2000 m for both single and paired banks) were extracted from the dataset and analyzed. A principle components analysis on physical habitat variables showed that depth was the most important variable in separating ROR and RF sites. Friedman tests comparing metric values among the four designs detected significant differences for all richness metrics at both types of sites and for catch per unit effort and percent tolerant species at ROR sites. Richness metrics were generally higher for the two 2000-m designs than for the two 1000-m designs. When plotted against cumulative electrofishing distance, the percent change in metrics declined sharply within approximately 1000 m, after which metrics usually varied by less than 10 percent. These data demonstrate that designs electrofishing 1000 m of shoreline are sufficient for bioassessments on boatable rivers similar to those in this study, regardless of whether the shoreline is along a single bank or distributed equally among paired banks. However, at sites with depths > 4 m, it may be advisable to employ nighttime electrofishing or increase day electrofishing designs to 2000 m.

JOURNAL Comparison of Macroinvertebrate Sampling Methods for Nonwadeable Streams 03/01/2005
Blocksom, K A. AND J E. Flotemersch. Comparison of Macroinvertebrate Sampling Methods for Nonwadeable Streams. ENVIRONMENTAL MONITORING AND ASSESSMENT 102:243-262, (2005).
Abstract: The bioassessment of nonwadeable streams in the United States is increasing, but methods for these systems are not as well developed as for wadeable streams. In this study, we compared six benthic macroinvertebrate field sampling methods for nonwadeable streams based on those used by three major programs (EMAP-SW, NAWQA, and Ohio EPA), at sixty sites across four tributaries to the Ohio River. Water chemistry samples and physical habitat measurements were collected at each site to assess relationships with macroinvertebrate metrics. Sites were divided into two groups: those influenced by navigational lock and dam structures built to support commercial traffic (restricted flow, or RF) and those free-flowing or having only lowhead dams (run-of-the-river, or ROR). The ROR and RF sites differed markedly in thalweg depth and substrate composition as well as macroinvertebrate composition. Regardless of site type, drift nets performed poorly and often could not be deployed due to inadequate flow. Metrics based on the passive Hester-Dendy artificial substrate samplers differed greatly from active sampling methods (i.e., D-frame and kick net sampling). Metric values were similar across active sampling methods, but the metrics significantly correlated with abiotic variables varied among methods and between ROR and RF sites. In both ROR and RF sites, active, net-based methods correlated with the most abiotic variables across metrics. These results emphasize that methods are not interchangeable, and the ability to detect certain stressors depends on the method of sampling.

JOURNAL Reference Values for Fish Exposure to PAH Contaminants: Comparison of Ohio and the Mid-Atlantic Region 02/01/2005
Cormier, S M. AND E.L C. Lin. Reference Values for Fish Exposure to PAH Contaminants: Comparison of Ohio and the Mid-Atlantic Region. Ecotoxicology 15(2):111-120, (2005).
Abstract: Reference values for exposure of wildlife to contaminants are needed to cost effectively determine if a site is contaminated and to rank sites that are above background levels. Epidemiological techniques originally developed for clinical chemistry and for determining exposures to humans in the workplace have been adapted to estimate background levels of exposure and used to evaluate exposures of fish to polyaromatic hydrocarbons in Ohio streams. The method for deriving estimates of background levels were described using bile metabolite data collected from fish sampled from randomly selected first to third-order streams and using fish sampled from Ohip EPA sites identified as least impacted based on measurements of habitat and fish assemblage. The calculated reference values for exposure to PAH were not significantly different for the two sampling designs. However, it is uncertain if the values derived in the Ohio studies can be applied to other regions because the data set may not be representative of the exposures in streams throughout the United States.
In this study, we calculated reference exposure values for BAP- and NAPH-type bile metabolites for the mid-Atlantic. Levels of PAH metabolites increase with increasing exposure. PAH, including benzo(a)pyrene (BAP) and naththlene (NAPH) were selected for this study because they have been associated with neoplasia in fish and humans. Reference values estimated for white sucker and common carp for the mid-Atlantic region were compared to those found for Ohio to ascertain if exposure levels were similar in the mid-West and the mid-Atlantic. Additionally, reference values were generated for two more species, hog sucker and rock bass, so that streams without white sucker or common carp could also be assessed. The objective of the study was to characterize metabolite levels associated with background exposure of PAH associated with an industrialized nation that could be applied to a larger geographic area.

JOURNAL Ecotoxicogenomics: Linkages Between Exposure and Effects in Assessing Risks of Aquatic Contaminants to Fish (Journal Article) 02/01/2005
MIRACLE, A. L. AND G. T. ANKLEY. Ecotoxicogenomics: Linkages Between Exposure and Effects in Assessing Risks of Aquatic Contaminants to Fish (Journal Article). REPRODUCTIVE TOXICOLOGY. Elsevier Science Ltd, New York, NY, 19:321-326, (2005).
Abstract: Understanding the biological effects of exposures to chemicals in the environment relies on classical methods and emerging technologies in the areas of genomics, proteomics, and metabonomics. Linkages between the historical and newer toxicological tools are currently being developed in order to predict and assess risk. Being able to classify chemicals and other stressors based on effects they have at the molecular, tissue, and organismal levels helps define a systems biology approach to development of streamlined, cost-effective, and comprehensive testing approaches for evaluating environmental hazards. The challenges of the individual technologies and the combinations of tools for ecotoxicogenomics are discussed in application to aquatic toxicology with a particular emphasis on fish testing.

JOURNAL New Host Data for the Leech Oligobdella Biannulate (Euhirudinea: Glossiphoniidae) 01/01/2005
Moser, W. E., R. W. Van Devender, R. R. Montanucci, C. D. Camp, AND D J. Klemm. New Host Data for the Leech Oligobdella Biannulate (Euhirudinea: Glossiphoniidae). The Journal of the North Carolina Academy of Science 121(1):36-40, (2005).
Abstract: The leech Oligobdella biannulata is a relatively rare species, endemic to mountain streams of the Southern Blue Ridge Physiographic Zone, exclusive of Virginia. Oligobdella biannulata was originally thought to be host specific to Desmognathus quadramaculatus. However, the host specificity of O. biannulata was amended after the discovery of additional salamander hosts. Oligobdella biannulata is currently thought to be host specific to salamanders of the subfamily Desmognathinae. Several additional amphibian host records, outside of the subramily Desmognathinae, were recorded while elucidating the distribution of O. biannulata.

JOURNAL Responses of Molecular Indicators of Exposure in Mesocosms: Common Carp (Cyprinus Carpio) Exposed to the Herbicides Alachlor and Atrazine 01/01/2005
Chang, L W., G P. Toth, D A. Gordon, D. W. Graham, J R. Meier, C. W. Knapp, F. J. deNoyelles, S. Campbell, AND D L. Lattier. Responses of Molecular Indicators of Exposure in Mesocosms: Common Carp (Cyprinus Carpio) Exposed to the Herbicides Alachlor and Atrazine. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. SETAC Press, Pensacola, FL, 24(1):190-197, (2005).
Abstract: Common carp (Cyprinus carpio) were treated in aquatic mesocosms with a single pulse of the herbicides atrazine or alachlor to study the bioavailability and biological activity of these herbicides using molecular indicators: Liver vitellogenin gene expression in male fish for estrogenic activity, liver cytochrome P450IA1 gene expression, and DNA damage in blood cells using the single-cell gel electrophoresis method. Both alachlor and atrazine showed dose related increases in DNA strand breaks at environmentally relevant concentrations (<100 ppb). Gene expression indicators showed that neither herbicide had estrogenic activity in the carp, whereas atrazine at concentrations as low as 7 ppb induced cytochrome P450IA1. These results support the study of molecular indicators for exposure in surrogate ecosystems to gauge relevant environmental changes following herbicide treatments.

JOURNAL Life History and Distribution of the Leech Oligobdella Biannulata (Moore, 1900) (Euhirudinea: Glossiphonnidae) 01/01/2005
Moser, W. E., R. W. Van Devender, AND D J. Klemm. Life History and Distribution of the Leech Oligobdella Biannulata (Moore, 1900) (Euhirudinea: Glossiphonnidae). COMPARATIVE PARASITOLOGY 72(1):17-21, (2005).
Abstract: Oligobdella biannulata (Moore, 1900) is a rare, endemic leech species originally described from a mountain stream near Blowing Rock, North Carolina. Specimens of O. biannulata were collected seasonally from Fall 1999, to Summer 2002, with new county records in North Carolina and South Carolina, and new state records from Georgia and Tennessee. Fifty-one percent of Desmognathus quadramaculatus and 50% of Desmognathus marmoratus were infested with O. biannulata. Desmognathus quadramaculatus exhibited a higher prevalence and mean intensity of infestation than D. marmoratus. Oligobdella biannulata leave their salamander hosts in late May to early July to lay eggs. Leeches lay 15-30 bright yellow, yolky eggs and brood them underneath their ventral surface. Eggs hatch in 10-20 days and in about 50 days, the hatchlings and adult search for a blood meal. Oligobdella biannulata re-attaches in late August to early October and over-winters on the host. When a desmognathine salamander host is found, the adult attaches, hatchlings leave the adult, and attach singly or in clusters on the limbs or axillary and inguinal regions, and blood-feed.

PRESENTATION Temporal and Spatial Population Genetic Analysis of Western, Northern, and Mexican Corn Rootworms in North America 12/14/2005
STOLZ, U. Temporal and Spatial Population Genetic Analysis of Western, Northern, and Mexican Corn Rootworms in North America. Presented at Conference on Diabrotica Genetics, Kansas City, MO, December 13 - 15, 2004.
Abstract: There is no abstract for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Application of Genomic and Proteomic Indicators to Characterize Exposure of Aquatic Organisms to Environmental Contaminants 11/14/2005
TOTH, G. P., I. KNOEBL, A. D. BIALES, D. L. LATTIER, D. C. BENCIC, AND J. M. LAZORCHAK. Application of Genomic and Proteomic Indicators to Characterize Exposure of Aquatic Organisms to Environmental Contaminants. Presented at SETAC, Baltimore, MD, November 13 - 17, 2005.
Abstract: Advances in molecular biological methods are continually being brought to bear on human health research, from a basic understanding of systems biology to identification of toxicity pathways for environmental stressors and to correlations of molecular indicators with physiological outcomes in human epidemiology studies. This prodigious research effort is beginning to be mirrored for aquatic organisms in the academic, government and private sector research laboratories. The U.S. EPA's National Exposure Research Laboratory (NERL) is partnering with other laboratories within E.P.A. as well as the DOE's Sandia National Laboratories and Joint Genome Institute to develop microarray resources for the fathead minnow. Combined with other gene discovery tools and proteomic analyses, NERL scientists are developing molecular methods to diagnose exposure to chemicals and chemical families, such as endocrine-disrupting chemicals (EDCs), pesticides and pharmaceuticals. These tools will be applied to answer real world questions about the extent and level of exposure to and effects on organisms in aquatic ecosystems. Current applications include analyses of estrogenic activity in a national scale study on wastewater treatment plant effluents, partnership with USGS in studying exposure issues related to the finding of intersex in smallmouth bass in the Potomac watershed and analyses of estrogenic activity in several cyprinids sampled during studies as part of the Environmental Monitoring and Assessment Program (EMAP) in the Ohio River watershed. Ultimately, a wide range of molecular indicators will be developed that are phenotypically-anchored to relevant ecological function (e.g., reproduction) and that will allow for characterization of exposure and effects before they are manifested at the tissue, organ, individual, or population level. Data for several projects in which these tools are used to diagnose exposure of aquatic organisms to EDCs in the field will be presented.

PRESENTATION Using Stable Isotopes to Track Biomagnification of Polychlorinated Biphenyls (PCBS) Through Stream Food Webs 11/14/2005
WALTERS, D., K. M. FRITZ, B. R. JOHNSON, AND J. M. LAZORCHAK. Using Stable Isotopes to Track Biomagnification of Polychlorinated Biphenyls (PCBS) Through Stream Food Webs. Presented at SETAC, Baltimore, MD, November 13 - 17, 2005.
Abstract: Most studies of biomagnification are from lentic systems, which are characterized by organic matter and sediment retention. However, biomagnification studies in streams are rare. This is surprising because PCBs and other persistent organic pollutants are known to biomagnify in aquatic ecosystems, and contaminated sediments are pervasive in stream ecosystems. Because it remains unclear if PCBs biomagnify and persist in streams, particularly in streams which are characterized by sediment and organic matter export, we investigated PCB contamination in Twelvemile Creek (Clemson, SC, USA), a stream that received > 400,000 lbs of PCBs from 1955-1978. Our goals were to determine if PCBs biomagnify in streams and to measure the relative importance of heterotrophic and autotrophic pathways for biomagnification. Sites were sampled during spring and fall 2003-04. Major components of the foodweb were analyzed for total PCBs. Biomagnification was apparent, and PCBs consistently increased with trophic level. We found no consistent patterns related to carbon pathways when the entire foodweb was considered. Analysis of individual trophic groups indicated that carbon source effects PCB concentrations. PCBs in grazing insects were more than double those in leaf shredding insects even though PCB concentrations were similar for periphyton and leaves. These results suggest that greater reliance on algal resources contributes to higher PCB concentrations within trophic levels. Our results show that PCBs biomagnify and persist in streams, but the importance of autotrophic and heterotrophic pathways is unclear.

PRESENTATION An Informatic Approach to Estimating Ecological Risks Posed By Pharmaceutical Use 11/14/2005
KOSTICH, M., J. M. LAZORCHAK, AND G. P. TOTH. An Informatic Approach to Estimating Ecological Risks Posed By Pharmaceutical Use. Presented at SETAC, Baltimore, MD, November 13 - 17, 2005.
Abstract: Pharmaceuticals administered to humans and other animals are often excreted from treated organisms as intact drug or as active metabolites. Some of these active materials have been shown to make their way into the environment. However, the environmental concentrations of the vast majority of pharmaceuticals and their metabolites are not known. The sensitivity of native organisms to chronic exposure to the doses of active material likely to be found in the environment is also not known. Direct determination of these important parameters is too expensive to perform on the entire pharmacopoeia, and a rational way of prioritizing individual drugs for more detailed study is needed. For many drugs sufficient information is available in the scientific literature and within regulatory filings to estimate the upper bound of environmental concentrations and most probable mechanisms of environmental toxicity. Although these estimates involve large confidence intervals, they are quickly and cheaply produced, and are probably the best available criteria for prioritizing drugs for more expensive direct tests of environmental impact. Here we describe a new method similar to that employed by the EU and by the US FDA for estimating risks of human prescription pharmaceuticals based on information found in regulatory filings as well as scientific and trade literature. Available data on usage patterns, metabolic transformation, and physical/chemical properties are fed into models of dilution, degradation, partition between matrices, and bioavailability in order to estimate effective environmental concentrations. Available data on mechanisms of action and modes of toxicity are considered together with cursory phylogenetic analysis to estimate the sensitivity of select native organisms to the estimated highest likely environmental concentrations of each drug. Scores produced by this procedure will be used to prioritize pharmaceuticals for more detailed analytical and toxicological follow-up. The applicability of modified versions of this method to over-the-counter pharmaceuticals and veterinary pharmaceuticals is also described.

PRESENTATION Development of a Smallmouth Bass Quantitative Real-Time Pcr Assay to Measure Vtg Gene Induction in Male Fish from the South Branch of the Potomac River 11/14/2005
KNOEBL, I., L. R. IWANOWICZ, C. O'BARA, AND V. BLAZER. Development of a Smallmouth Bass Quantitative Real-Time Pcr Assay to Measure Vtg Gene Induction in Male Fish from the South Branch of the Potomac River. Presented at SETAC, Baltimore, MD, November 13 - 17, 2005.
Abstract: A high incidence of intersex bass, primarily male smallmouth bass with previtellogenic oocytes, exists in the south branch of the Potomac River. Exposures to endocrine disrupting chemicals (EDCs) may be the cause of these abnormalities. Potential sources of EDCs to the river are municipal sewage treatment plant discharges and poultry and cattle feedlots located in close proximity to the river. In an attempt to determine whether EDCs, particularly estrogenic chemicals, from these effluents and discharges may be contributing to the observed intersex in fish, we have developed a quantitative real-time (Q-PCR) assay for smallmouth bass to measure the induction of the vitellogenin (VTG) gene in male fish. We isolated a VTG1 gene sequence using degenerate primers in a PCR reaction. The PCR products were cloned using E. coli cells and the clones were isolated and sequenced to confirm the identity of the gene fragment. The clones provided a template to generate a standard curve for smallmouth bass VTG1 and the gene sequence was then used to design Q-PCR primers. The Q-PCR assay was optimized and then used to measure VTG levels in smallmouth bass collected from various locations on the south branch of the Potomac River.

PRESENTATION Alterations in the Transcriptome and Proteome of Zebrafish (Danio Rerio) Exposed to Fadrozole, a Model Aromatase Inhibitor 11/14/2005
KNOEBL, I., R. WANG, G. P. TOTH, E. F. ORLANDO, M. S. SEPULVEDA, D. H. MILLER, E. J. DURHAM, K. M. JENSEN, E. A. MAKYNEN, AND D. L. VILLENEUVE. Alterations in the Transcriptome and Proteome of Zebrafish (Danio Rerio) Exposed to Fadrozole, a Model Aromatase Inhibitor. Presented at SETAC, Baltimore, MD, November 13 - 17, 2005.
Abstract: Fadrozole is a reversible, competitive inhibitor of aromatase activity and therefore an endocrine-disrupting compound (EDC) that disrupts steroidogenesis by inhibiting the conversion of testosterone to 172-estradiol. While fadrozole is a therapeutic drug with generally no environmental relevance, it does serve as a relatively specific aromatase inhibitor and, as such, is useful for the discovery of potential diagnostic markers. In this study, we examined the effects of fadrozole on gene and protein expression in tissues comprising the hypothalamic-pituitary-gonadal (HPG) axis in reproductively mature zebrafish (Danio rerio). Fish were exposed to two concentrations of fadrozole (25 and 100 �g/L) or control water. Transcriptome and proteome changes in brain, liver, and gonads were determined using 22,000 gene microarrays and two-dimensional gel electrophoresis followed by peptide analysis via mass spectroscopy, respectively. Brain and gonad aromatase activities were also determined. Fathead minnows (Pimephales promelas) exposed to fadrozole exhibit altered reproductive biology (e.g., decreased plasma estradiol and vitellogenin and decreased fecundity). Integrating these data and the alterations in gene and protein expression in the zebrafish documented here will help identify key genes and proteins of the HPG axis affected by fadrozole exposure, thereby providing a more definitive description of its modes/mechanisms of action (MOA). The combination of genomic and proteomic approaches along with whole organism endpoints and future metabonomic work and systems-biology modeling will identify new molecular biomarkers of exposure to fadrozole and other compounds with similar MOA and link these biomarkers to effects that are relevant for both diagnostic and predictive risk assessments.

PRESENTATION Changes in Gene and Protein Expression in Zebrafish (Danio Rerio) Following Exposure to Environmentally-Relevant Endocrine Disrupting Compounds (Edcs) 11/14/2005
BENCIC, D. C., A. L. MIRACLE, D. L. LATTIER, J. M. LAZORCHAK, N. D. DENSLOW, K. H. WATANABE, T. L. WHITEHEAD, T. W. COLLETTE, M. D. KAHL, AND G. T. ANKLEY. Changes in Gene and Protein Expression in Zebrafish (Danio Rerio) Following Exposure to Environmentally-Relevant Endocrine Disrupting Compounds (Edcs). Presented at SETAC, Baltimore, MD, November 13 - 17, 2005.
Abstract: Endocrine-disrupting chemicals (EDCs) are increasingly being reported in waterways worldwide and have been shown to affect fish species by disrupting numerous aspects of development, behavior, reproduction, and survival. Furthermore, new data have suggested that the reduced reproductive fitness resulting from EDC exposure may have a significant impact at biological levels beyond the individual, such as the population level. In this study, we examined the effects of the synthetic steroids 17�-ethinylestradiol (EE2) and 17�-trenbolone (trenbolone) on gene and protein expression in the liver and gonads of reproductively mature zebrafish (Danio rerio). These compounds are highly specific and potent agonists of estrogen and androgen receptors, respectively, and are used extensively in the U.S. as an active ingredient in many oral contraceptives (EE2) or a growth promoter in beef cattle (trenbolone). Both have been detected in aquatic environments and are therefore relevant as environmental contaminants. Fish were exposed to two concentrations of EE2 (30 or 100 ng/L) or trenbolone (0.3 or 3.0 �g/L) or control water for up to 96 hours in a flow-through system. Changes in the transcriptome and proteome were measured using microarrays followed by QPCR validation and two-dimensional gel electrophoresis followed by peptide analysis via mass spectroscopy, respectively. The differential expression profiles will provide molecular diagnostic and predictive biomarkers for risk assessment, and along with metabolite profiles and whole organism endpoints from ongoing projects, will further enhance source-to-outcome linkages and support computational modeling. Integration of these zebrafish gene and protein expression data sets with definitive tests in the fathead minnow (Pimephales promelas) will help establish toxicity pathways of environmentally-relevant responses in a systems- and population-modeling context.

PRESENTATION Sensitivity Difference Among Various Strains of Hyallela Azteca 11/14/2005
HARING, H. J., J. MARKERT, J. M. LAZORCHAK, AND M. E. SMITH. Sensitivity Difference Among Various Strains of Hyallela Azteca. Presented at SETAC, Baltimore, MD, November 13 - 17, 2005.
Abstract: The North American amphipod Hyalella azteca is widely used in toxicity testing. H. azteca has a broad geographic distribution, and genetic evidence suggests that populations diverged from each other long ago. The importance of this genetic divergence to toxicity testing is unclear. Here we report the LC50 results for two different toxicants, Cu2+ and NH3, from tests with geographically isolated strains of H. azteca from seven academic and government laboratories and one wild strain. The strains were reared and tested under identical conditions. These tests were 96 h renewed acute toxicity tests conducted in triplicate using serial dilutions up to 500 ug/l CuSO4 and 500 mg/l (NH4)2HPO4. The Cu2+ LC50s ranged from 105.76 ug/l to126.14 ug/l. The NH3 LC50s ranged from 3.88 mg/l to 5.18 mg/l. Of the eight strains tested with each toxicant, none were found to differ statistically based on the LC50 data generated. Therefore, it appears no sensitivity differences exist among different strains of H. azteca tested thus far using Cu2+ and NH3 as toxicants.

PRESENTATION Dna Damage and External Lesions in Brown Bullhead from Contaminated Habitats 11/13/2005
MEIER, J. R., Y. YANG, L. W. CHANG, AND P. C. BAUMANN. Dna Damage and External Lesions in Brown Bullhead from Contaminated Habitats. Presented at SETAC, Baltimore, MD, November 13 - 17, 2005.
Abstract: The single cell gel electrophoresis ("Comet") assay was used to compare levels of DNA damage in brown bullheads (Ameiurus nebulosus) collected from three known contaminated locations, the Cuyahoga River, Ashtabula River, and Ashumet Pond (Cape Cod), with brown bullheads collected from three paired reference sites, Old Woman Creek, Conneaut River, and Great Herring Pond, respectively. Blood was sampled from the caudal vein of each fish and the Comet assay was conducted on erythrocytes. Raised external lesions and barbel abnormalities were also recorded. The results demonstrated that fish from the three contaminated sites each suffered significantly higher DNA damage (measured as % tail DNA, tail length and tail moment) than fish from their respective reference sites. The gender and age of the fish did not affect the Comet parameters. Positive relationships were observed between levels of DNA damage and presence of external abnormalities. This study provides evidence that the Comet assay is sufficiently sensitive to detect exposure of natural fish populations to environmental levels of genotoxic contaminants, and suggests this method may be useful as a recent or predictive indicator of carcinogenic exposure in aquatic ecosystems.

PRESENTATION Establishing the Importance of Headwater Streams: Concepts and Preliminary Applications 11/09/2005
FRITZ, K. M., B. R. JOHNSON, R. A. BURKE, P. J. WIGINGTON JR, B. H. HILL, C. T. NIETCH, AND R. J. BRUINS. Establishing the Importance of Headwater Streams: Concepts and Preliminary Applications. Presented at Headwaters Workgroup, AWRA Meeting, Seattle, WA, November 09, 2005.
Abstract: Oral presentation, Headwaters Workgroup, in association with the AWRA Meeting, Seattle, WA.

PRESENTATION Carbon, Contaminants and Creeks: Using Stable Isotopes and PCBs to Track Energy Flow Through Stream Foodwebs 11/04/2005
WALTERS, DAVID M., K. M. FRITZ, B. R. JOHNSON, S. RYBCZYNSKI, AND J. M. LAZORCHAK. Carbon, Contaminants and Creeks: Using Stable Isotopes and PCBs to Track Energy Flow Through Stream Foodwebs. Presented at University of Georgia Institute of Ecology, Athens, GA, November 04, 2005.
Abstract: Oral presentation at the University of Georgia Institute of Ecology, November 4, 2005.

PRESENTATION Development of a Large River Bioassessment Protocol (Lr-Bp) for Macroinvertebrates: Pilot Results from Midwestern Rivers 11/03/2005
FLOTEMERSCH, J. E., K. A. BLOCKSOM, AND B. R. JOHNSON. Development of a Large River Bioassessment Protocol (Lr-Bp) for Macroinvertebrates: Pilot Results from Midwestern Rivers. Presented at Northwest Biological Assessment Workshop, Townsend, WA, November 02 - 04, 2005.
Abstract: There is no abstract for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Potential Use of Benthic Algae as Hydrologic Indicators for Headwater Streams: Some Data Exploration 10/31/2005
GREENWOOD, J. AND K. M. FRITZ. Potential Use of Benthic Algae as Hydrologic Indicators for Headwater Streams: Some Data Exploration. Presented at North American Diatom Symposium, Mobile, AL, October 31 - November 04, 2005.
Abstract: Benthic algae were sampled to determine the utility of algal communities as indicators of hydrologic regime as part of a national survey involving habitat measurements and community assessments. Streams from four forests near Cincinnati were classified according to hydrologic permanence as ephemeral, intermittent or perennial. Ordination of algal community data did not produce visibly distinct clusters by hydrologic permanence. However, similarity analysis revealed significant differences among all hydrologic categories. Ephemeral streams supported the lowest total densities and biomass but the highest cyanobacteria densities. Intermittent and perennial streams were both dominated by diatoms and contained similar algal cell densities and biomass. Indicator species analysis suggested that some diatom taxa may distinguish ephemeral and perennial streams. Results suggest that benthic algal data may be useful in assessing hydrologic regimes of headwater streams.

PRESENTATION U.S. EPA's Research on the Ecological Exposure, Effects and Risk Management of Endocrine Disruption Chemicals and Pharmaceuticals 10/27/2005
LAZORCHAK, J. M., C. G. DAUGHTON, G. T. ANKLEY, J. E. TIETGE, EARL E. GRAY, V. S. WILSON, R. W. FLICK, A. D. BIALES, D. L. LATTIER, D. C. BENCIC, M. KOSTICH, M. MILLS, T. L. JONES-LEPP, L. I. OSEMWENGIE, K. M. SCHENCK, AND S. GLASSMEYER. U.S. EPA's Research on the Ecological Exposure, Effects and Risk Management of Endocrine Disruption Chemicals and Pharmaceuticals. Presented at South Platte Forum, Longmont, CO, October 27, 2005.
Abstract: There is no abstract available for this product. If further information is needed, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Effect of Flow Regime on Fish-Habitat Relationships in a Mid-Western River 09/12/2005
WALTERS, DAVID M., F. B. DANIEL, M. B. GRIFFITH, AND F. H. MCCORMICK. Effect of Flow Regime on Fish-Habitat Relationships in a Mid-Western River. Presented at American Fisheries Society, Anchorage, AL, September 11 - 15, 2005.
Abstract: Numerous studies have shown interrelationships among stream fishes, habitat and land use, but it is unclear how flow regime affects these relationships. We hypothesized that habitat would better predict fishes in streams with stable flows. Habitat should be less predictive in unstable regimes due to the overriding importance of episodic droughts. We tested this hypothesis with data collected over five years in thirty-five tributaries of the Little Miami River in Ohio.

PRESENTATION Invasion Dynamics of Red Shiners (Cyprinella Lutrensis) in Southeastern Streams 09/12/2005
WALTERS, DAVID M., M. J. BLUM, N. BURKHEAD, B. FREEMAN, B. RASHLEIGH, AND B. PORTER. Invasion Dynamics of Red Shiners (Cyprinella Lutrensis) in Southeastern Streams. Presented at American Fisheries Society, Anchorage, AL, September 11 - 15, 2005.
Abstract: Red shiners have invaded a range of North American ecosystems, including several southeastern U.S. river drainages. A principle consequence of these invasions is extirpation of native congeners, either through competition or hydridization. We are conducting research to identify the key ecological and genetic drivers of red shiner colonization across the Coosa River system in Georgia and Alabama.

PRESENTATION Setting Expectations for the Ohio River Fish Index Based on in-Stream Habitat 09/12/2005
EMERY, E. B., K. A. BLOCKSOM, J. A. THOMAS, AND DAVID M. WALTERS. Setting Expectations for the Ohio River Fish Index Based on in-Stream Habitat. Presented at American Fisheries Society, Anchorage, AK, September 11 - 15, 2005.
Abstract: The use of habitat criteria for setting fish community assessment expectations is common for streams, but a standard approach for great rivers remains largely undeveloped. We developed assessment expectations for the Ohio River Fish Index (ORFIN) based on measures of in-stream habitat. We sampled fishes and habitat for 627 Ohio River locales and examined seven measures of in-stream fish cover, depth, and substrate composition. Multivariate analysis identified three distinct habitat types (cobble dominated, sand dominated, and mixed substrate) based solely on sediment composition. Some aspects of fish assemblage structure corresponded to spatial variability in habitat types and influenced ORFIN scores. As a result, we set different expectations for ORFIN scores for each of the three habitat types. The findings from this study provide baseline information to allow resource managers to develop more accurate expectations for the Ohio River Fish Index based on habitat, information that will serve to improve the assessment, reporting and decision-making processes.

PRESENTATION An Informatic Approach to Estimating Ecological Risks Posed By Pharmaceutical Use 08/24/2005
KOSTICH, M., J. M. LAZORCHAK, AND G. P. TOTH. An Informatic Approach to Estimating Ecological Risks Posed By Pharmaceutical Use. Presented at Pharmaceuticals in the Environment Workshop, Las Vegas, NV, August 23 - 25, 2005.
Abstract: A new method for estimating risks of human prescription pharmaceuticals based on information found in regulatory filings as well as scientific and trade literature is described in a presentation at the Pharmaceuticals in the Environment Workshop in Las Vegas, NV, August 23-25, 2005.

PRESENTATION Factors Controlling Hydrologic Permanence of Headwater Streams 05/24/2005
FRITZ, K. M., B. R. JOHNSON, AND D. M. WALTERS. Factors Controlling Hydrologic Permanence of Headwater Streams. Presented at North American Benthological Society, New Orleans, LA, May 23 - 27, 2005.
Abstract: Headwater streams compose the majority of stream miles within most drainages. Interest in monitoring headwater streams is increasing because headwater streams are vital linkages between upland land use and downstream water bodies. However, traditional stream assessment tools are often unsuitable because many headwater streams are prone to natural drying. Our objective was to identify physical characteristics of headwater reaches that are indicative of hydrologic permanence, a critical first step in applying a stream assessment. We surveyed 61 reaches along 17 headwater streams across four forests in Indiana, Kentucky and Ohio. Reaches varied in hydrologic permanence over the two year study. Exploratory data analysis (CART and discriminant analysis) was used to identify physical parameters for classifying reaches by hydrologic permanence. Drainage area was a consistent parameter discriminating permanence categories and consistently separated ephemeral from perennial and intermittent reaches. Secondary parameters that distinguished intermittent from ephemeral and perennial reaches included bankfull width, maximum pool depth, and channel entrenchment. These factors represent basin and reach scales, suggesting that hydrologic permanence in stream networks should be investigated in a hierarchical context.

PRESENTATION Using Genomics and Proteomics to Diagnose Exposure of Aquatic Organisms to Environmental Contaminants 05/24/2005
KNOEBL, I., A. L. MIRACLE, D. L. LATTIER, D. C. BENCIC, A. D. BIALES, AND J. M. LAZORCHAK. Using Genomics and Proteomics to Diagnose Exposure of Aquatic Organisms to Environmental Contaminants. Presented at SETAC, Lille, FRANCE, May 23 - 26, 2005.
Abstract: Advances in molecular biology allow the use of cutting-edge genomic and proteomic tools to assess the effects of environmental contaminants on aquatic organisms. Techniques are available to measure changes in expression of single genes (quantitative real-time PCR) or to measure global changes in gene expression (gene arrays) after exposure to toxicants or other stressors. In addition, using proteomics techniques, changes in protein synthesis can also be measured. Detection of anomalies at the genomic/proteomic level allows identification of adverse effects at the molecular level, soon after exposure and before they are manifested at the tissue, organ, individual, or population level. The U.S. Environmental Protection Agency is developing several methods to diagnose exposure to certain chemicals and chemical families (endocrine disrupting chemicals, pesticides, etc.). Current research projects in the development of gene arrays, quantitative real-time PCR and proteomics will be described. In addition, data for several projects in which these tools are used to diagnose exposure of aquatic organisms to endocrine disrupting chemicals in the field will be presented.

PRESENTATION Are Salamanders Useful Indicators of Hydrologic Permanence in Headwater Streams? 05/24/2005
JOHNSON, B. R. AND K. M. FRITZ. Are Salamanders Useful Indicators of Hydrologic Permanence in Headwater Streams? Presented at North American Benthological Society, New Orleans, LA, May 23 - 27, 2005.
Abstract: Regulatory agencies need appropriate indicators of stream permanence to aid in jurisdictional determinations for headwater streams. We evaluated salamanders as permanence indicators because they are often abundant in fishless headwaters. Salamander and habitat data were collected in spring and summer 2003 from 59 sites located longitudinally along 17 forested streams in Kentucky, Indiana, and Ohio. Larval Eurycea bislineata/cirrigera dominated all forests, and their abundances were highly correlated with drainage areas and channel dimensions. Appalachian streams were more diverse and had intermittent sites with more Desmognathus and Gyrinophilus spp. Of 22 sites where larvae were collected in spring, nine sites subsequently dried in summer, suggesting salamanders either emigrated or died. We therefore only used taxa with multi-year larval stages as indicators of perennial water. Salamander larvae >1 yr old were collected from each locality in drainage areas d0.17 km2. However, these older larvae were often found in isolated pools that serve as refugia during dry periods. Findings suggest salamanders with multi-year larval periods can indicate perennial waters and that their use is more effective in Appalachia where abundance and diversity are high.

PRESENTATION Comparison of USEPA Field Sampling Methods for Benthic Macroinvertebrate Studies 05/23/2005
KLEMM, D. J., M. D. MOEYKENS, M. HUDY, K. A. BLOCKSOM, W. T. THOENY, AND J. K. WHALEN. Comparison of USEPA Field Sampling Methods for Benthic Macroinvertebrate Studies. Presented at North American Benthological Society, New Orleans, LA, May 22 - 27, 2005.
Abstract: Two U.S. Environmental Protection Agency (USEPA) macroinvertebrate sampling protocols were compared in the Mid-Atlantic Highlands region. The Environmental Monitoring and Assessment Program (EMAP) wadeable streams protocol results in a single composite sample from nine transects, whereas the rapid bioassessment protocol (RBP) II consists of a single composite sample from four locations within a riffle. Separate macroinvertebrate samples were collected by USEPA and U.S. Forest Service (USFS) using both sampling protocols from 12 streams in 2002. Samples were sub-sampled to 300 organisms and identified to lowest taxonomic level possible. Non-metric multidimensional scaling (NMS) was used to determine major patterns in macroinvertebrate assemblages, and Bray-Curtis similarity analysis was used to explore differences in species composition between methods. No distinct differences were found between samples collected using the two sampling methods. Comparison of taxa richness, functional feeding group, and habit between sampling methods all showed 80% or higher similarity.

PRESENTATION Using Stable Isotopes to Track Biomagnification of Polychlorinated Biphenyls (PCBS) Through Stream Food Webs 05/23/2005
WALTERS, DAVID M., K. M. FRITZ, B. R. JOHNSON, AND J. M. LAZORCHAK. Using Stable Isotopes to Track Biomagnification of Polychlorinated Biphenyls (PCBS) Through Stream Food Webs. Presented at North American Benthological Society, New Orleans, LA, May 22 - 28, 2005.
Abstract: Biomagnification studies of PCBs in streams are rare, even though PCBs are known to biomagnify and persist in aquatic ecosystems. We investigated PCB contamination in Twelve Mile Creek (Clemson, South Carolina, U.S.A.), a stream that received >400,000 lbs. of PCBs from 1955-1978. Our goals were to determine if PCBs biomagnify in streams and to measure the relative importance of heterotrophic and autotrophic pathways for biomagnification.

PRESENTATION A Methods Comparison for Collecting Macroinvertebrates in the Ohio River 05/23/2005
WOOTEN, M., E. EMERY, B. R. JOHNSON, AND K. A. BLOCKSOM. A Methods Comparison for Collecting Macroinvertebrates in the Ohio River. Presented at North American Benthological Society, New Orleans, LA, May 22 - 28, 2005.
Abstract: Collection of representative benthic macroinvertebrate samples from large rivers has been challenging researchers for many years. The objective of our study was to develop an appropriate method(s) for sampling macroinvertebrates from the Ohio River. Four existing sampling methods were compared in the Markland Pool of the Ohio River.

PRESENTATION Biological Assessment of Large Rivers in the U.S. Environmental Protection Agency Region 5: An Inter-Agency Collaboration 05/16/2005
JOHNSON, B. R., E. EMERY, J. THOMAS, J. M. LAZORCHAK, J. E. FLOTEMERSCH, K. A. BLOCKSOM, AND C. YODER. Biological Assessment of Large Rivers in the U.S. Environmental Protection Agency Region 5: An Inter-Agency Collaboration. Presented at 2005 EPA Science Forum, Washington, DC, May 16 - 18, 2005.
Abstract: Biological assessment of our nation's large rivers has lagged behind that of smaller streams because of a lack of appropriate methods, necessary training, and disturbance indicators. The need for assessment of large rivers has risen along with an increasing awareness of pollutant runoff, cumulative stressor effects, and observed degradation in coastal zones. The NERL in Cincinnati and the ORSANCO are addressing this issue through a collaborative effort to develop standardized assessment methods and appropriate biological indicators for large rivers of the U.S. Environmental Protection Agency (U.S. EPA) Region 5. The Environmental Monitoring and Assessment Program (EMAP) was developed to provide monitoring designs and indicators that yield unbiased estimates of ecological conditions, but it had not been previously applied to large river resources. Through Regional-EMAP (R-EMAP), the ORSANCO and MBI are using standardized methods to sample fish assemblages at 30 randomly selected sites on each of up to 11 large river tributaries to the Ohio and Mississippi Rivers from 20042006. The Regional Methods Program (designated specifically for methodological needs of states, regions, and tribes) is funding the NERL to sample a subset of the R-EMAP target rivers to provide multi-assemblage assessments. The NERL is using a standardized Large River Bioassessment Protocol (LR-BP) to collect aquatic invertebrates, phytoplankton, and water chemistry at 25 sites on each of six target rivers in 20042005. This collaborative effort will provide the necessary assessment tools for states and tribes to begin developing biocriteria for these vital large river resources.

PRESENTATION Assessing Endocrine-Disrupting Chemical Exposure in Indigenous Aquatic Populations in the Ohio River 05/16/2005
BIALES, A. D., B. R. JOHNSON, J. E. FLOTEMERSCH, E. EMERY, AND J. M. LAZORCHAK. Assessing Endocrine-Disrupting Chemical Exposure in Indigenous Aquatic Populations in the Ohio River. Presented at 2005 EPA Science Form, Washington, DC, May 16 - 18, 2005.
Abstract: The NERL has launched a collaborative study with the ORSANCO to determine the degree of ecologically relevant endocrine-disrupting chemical (EDC) exposure in the New Cumberland Pool of the Ohio River under the Environmental Monitoring and Assessment Program - Great Rivers Project (EMAP-GRE). EDCs are common to oral contraceptives and are often present at relatively high levels in sewage effluents from metropolitan areas as well as runoffs from cattle farms. There are increasing examples of male fish displaying female sex characteristics in the waterways of the United States and Europe. EDCs have been shown to affect multiple aspects of fish biology including fecundity, mortality, and development. These biological endpoints require large-scale morphological or behavioral changes and constant long-term exposure. Therefore, before these indicators are manifest at measurable levels, indigenous populations have already undergone significant environmental stress. In contrast, changes in gene expression are often the initial and direct response of biological systems to EDCs and other environmentally relevant toxicants and are measurable at exceedingly low levels. Gene expression is becoming a commonly used diagnostic tool in human health for cancer research and is now gaining acceptance in the ecological world. The most well established genetic indicator of EDC exposure in aquatic systems is the egg precursor protein vitellogenin (Vg), expressed in reproductive females and quiescent in males. The NERL Cincinnati recently established a sensitive experimental system capable of reproducibly measuring changes in Vg mRNA abundance in response to a variety of estrogenic, hormonal EDCs. To field-test our experimental system, ORSANCO will collect samples of two indigenous fish species, the smallmouth bass and the smallmouth buffalo. This project will validate the ecological relevance of aberrant male Vg expression in wild populations by integrating other more established indicators of ecological disruption also surveyed under the EMAP Great Rivers Project. We will critically evaluate indicators of ecological disturbances at different spatial scales ranging from the individual through the landscape level to determine the most appropriate indices of environmental health. Finally, we will gain important information as to the extent of EDC exposure in aquatic ecosystems of the New Cumberland Pool of the Ohio River.

PRESENTATION A Comparison of Two Rapid Biological Assessment Sampling Methods for Macroinvertebrates 05/16/2005
AUTREY, B. C., K. A. BLOCKSOM, M. PASSMORE, L. REYNOLDS, AND J. E. FLOTEMERSCH. A Comparison of Two Rapid Biological Assessment Sampling Methods for Macroinvertebrates. Presented at 2005 EPA Science Forum, Washington, DC, May 16 - 18, 2005.
Abstract: In 2003, the Office of Research and Developments (ORD's) National Exposure Research Laboratory initiated a collaborative research effort with U.S. EPA Region 3 to conduct a study comparing two rapid biological assessment methods for collecting stream macroinvertebrates. One method focuses sampling in a single fast-water habitat (riffles), and the other samples multiple habitats within a stream. The single-habitat method has been widely used in the U.S. for biological assessment of streams for over a decade. However, Region 3 biologists recognized that in the Piedmont and Northern Piedmont regions of the U.S., riffle habitat is less abundant in streams. In streams of these regions, the traditionally used single-habitat method was compared with the more recently proposed multiple-habitat sampling method to determine whether the multiple-habitat method is more effective in these streams. The success of this study depended on a strong collaboration between U.S. EPA Region 3 and the ORD to select sites, conduct field sampling, and analyze the data. While the ORD scientists were responsible for careful analysis of those data, Region 3 biologists were instrumental in helping the NERL put research results into a context useful to state agencies. Region 3 was able to involve biologists at the Virginia Department of Environmental Quality in this process, providing valuable feedback on specific aspects of analysis. As a result of the collaboration between the ORD and Region 3, the results of this methods comparison study will have a more immediate impact on decision-making at the state level.

PRESENTATION Improving the Reliability of Microarrays for Toxicology Research: A Collaborative Approach 05/16/2005
TIMLIN, J. A., E. V. THOMAS, G. HEFFELFINGER, R. WANG, A. L. MIRACLE, AND G. P. TOTH. Improving the Reliability of Microarrays for Toxicology Research: A Collaborative Approach. Presented at 2005 EPA Science Forum, Washington, DC, May 16 - 18, 2005.
Abstract: Microarray-based gene expression profiling is a critical tool to identify molecular biomarkers of specific chemical stressors. Although current microarray technologies have progressed from their infancy, biological and technical repeatability and reliability are often still limiting factors in many experiments. Researchers at Sandia National Laboratories have developed advanced measurement scientific techniques for improving microarray data generation and analysis. Researchers at the U.S. EPA (Ecological Exposure Research Division/NERL) have joined in collaboration with Sandia National Laboratories to apply these novel methods to DNA microarrays from the wild aquatic species, Pimephales promelas (fathead minnow). These unique capabilities include hyperspectral imaging technology to assess quality control of array manufacture, statistically robust array designs to permit the highest confidence in the resulting data, and multivariate data analysis and visualization tools to better facilitate data mining and biomarker identification. When successful, this integrated approach to improving microarray platform will permit extraction of the highest-quality data from a minimal set of experiments, thus facilitating a more accurate and sensitive determination of specific molecular diagnostic indicators to monitor bioavailable stressors in aquatic ecosystems. This monitoring effort is critical to the U.S. EPA's exposure characterization as part of its ecological risk assessment mission.

PRESENTATION National Wwtp Effluent Study 05/16/2005
LAZORCHAK, J. M., M. MILLS, AND G. SAYLES. National Wwtp Effluent Study. Presented at 2005 EPA Science Forum, Washington, DC, May 16 - 18, 2005.
Abstract: Reports of potential wildlife risk from exposure to environmental estrogens emphasize the need to better understand both estrogenic presence and persistence in treated wastewater effluents. In addition to wildlife exposure, human exposure should also be examined, especially in situations when estrogenic effluents may return to a drinking water supply. This potential has been examined in rivers and reservoirs in the United Kingdom, where they found reduced estrogenicity downstream from wastewater outfalls and no estrogenicity in reservoirs receiving these waters. In 2000, the NERL and the University of North Texas collaborated in a study in which the toxicity and estrogenicity of a final treated municipal effluent was examined. Male fathead minnows were deployed in the effluent for three weeks. VTG protein, Gonado-Somatic Index (GSI), Hepato-Somatic Index (HSI), and secondary sexual characteristics were biomarkers used in fish models to assess aqueous estrogenicity. VTG gene expression was also measured. There was a very good correspondence in the biomarker and gene expression results. This study provided evidence that the VTG gene expression assay could be used to assess estrogenic EDC exposures in effluents.
In 2002 and 2003, the NERL and NRMRL contacted our ten regional biologists, regional science liaisons, U.S. Environmental Protection Agency (U.S. EPA) inspectors, state U.S. EPA inspectors, and municipal plant operators to voluntarily collect up to 50 effluents and ship them to Cincinnati for male and female fathead minnow exposures. The objective of this study was to determine whether adult male or female fathead minnows exposed to a municipal WWTP effluent elicited a change in VTG gene expression above or below a lab water control. The goal was to use VTG gene expression results to assess whether certain types of domestic WWTPs or operations are more effective in removing estrogenic EDCs. Of the 50 effluents tested, 13 (26%) effluents upregulated VTG expression in male fathead minnows, two effluents downregulated VTG expression in female fathead minnows, and two effluents that were resampled and tested demonstrated upregulation of VTG in male fathead minnows. This study demonstrated the utility of using the U.S. EPA's male fathead minnow VTG gene expression assay as a tool for screening effluents for estrogenic EDCs. Additional assessment of individual operational information of those wastewater plants demonstrating estrogenicity and similar treatment facilities that did not show estrogenicity need to take place to determine whether certain types of treatment processes and/or operations are more efficient at removing estrogenic EDCs than others. Chemical analyses of effluent samples are currently underway. Results will be used to look for the relationships among the detected estrogens and androgens to gene expression results.

Impacts and Outcomes

This research study initiated the ORD's efforts to monitor EDCs on more than a local scale. Two ORD national laboratories collaborated to expand the scope of a local WWTP study to include samples from several states. The feasibility of sample collection, shipment, and analysis at this scale was shown. Positive findings are setting the research agenda for both future studies and development of additional indicators. Additional studies are currently being planned to look at relationships between the presence of EDCs in effluents and in-stream adverse exposures. An EDC multiyear plan, "Annual Performance Measure," has been generated on the gene expression results and is being distributed to the regions and the Office of Water.

PRESENTATION Regional Transport and Secondary Spread of Invasive Species Across Pacific Estuaries 05/16/2005
BLUM, M. J., M. BAGLEY, J. CABREZA, A. OTA, AND E. MCNAUGHTON. Regional Transport and Secondary Spread of Invasive Species Across Pacific Estuaries. Presented at 2005 EPA Science Forum, Washington, DC, May 16 - 18, 2005.
Abstract: San Francisco Bay is considered to be the most highly invaded estuary in North America, and is suspected of acting as a local source pool for secondary invasions of other Pacific estuaries. With support from the Regional Applied Research Effort programs in EPA Regions 9 and 10, we have initiated research to determine whether invasive species introduced to San Francisco Bay are spreading to other Paciifc estuaries via regional ship traffic. This work will identify and characterize invasion pathways across Pacific estuaries by determining whether populations of invasive species distributed across Pacific estuaries are derived from San Francisco Bay populations as opposed to overseas sources. We are addressing this concern by evaluating patterns of genetic diversity across populations of ten invasive species sampled from California to Alaska. To determine whether ballast transport by regional shipping traffic is an important vehicle acting to spread invasive species from San Francisco Bay to other major Pacific estuaries, we are developing genetic screening tools to determine whether the ten invasive species are being carried in ballast originating from San Francisco Bay. By characterizing invasion pathways and transport profiles from cross-species comparisons, this research will facilitate early detection and monitoring programs, and will improve ballast water best management practices designed to eliminate or restrict the spread of invasive species across Pacific estuaries. Results from the proposed research may also affect policy development for ballast regulation. Current ballast management programs focus on international shipping, but confirmation that San Francisco is a local source seeding other Pacific estuaries with exotic species would call for implementing stronger interstate and coastal ballast water regulations. Molecular screening tools designed to detect exotic species in ballast will also provide rapid and powerful methods for verifying whether vessels have complied with current management requirements.

PRESENTATION Headwater Intermittent Streams Study: Collaboration Across the Nation 05/16/2005
FRITZ, K. M., B. R. JOHNSON, DAVID M. WALTERS, J. E. FLOTEMERSCH, M. PASSMORE, D. MCDONALD, J. KURTENBACH, E. HAMMER, G. HAYSLIP, AND L. HERGER. Headwater Intermittent Streams Study: Collaboration Across the Nation. Presented at 2005 EPA Science Forum, Washington, DC, May 16 - 18, 2005.
Abstract: Headwater streams are the most abundant and widespread of our nation's surface waters, yet little guidance is available specific to these resources. Headwater streams lie at the terrestrial-aquatic interface, both spatially because of their narrow channels and landscape position and temporally because of their relatively young geological age and recent transition from terrestrial to aquatic habitats. In fact, many have physical characteristics of both aquatic and terrestrial habitats because of seasonal flowing and drying phases. Natural drying has a strong influence on biological communities and can confound the use of traditional stream assessment tools. As a result, headwater stream ecosystems are a challenging environment for addressing regulatory issues. Through the Regional Methods Program (research funding specifically designated for methodological needs of states, regions, and tribes), the ORD's National Exposure Research Laboratory in Cincinnati is developing methods for assessing headwater streams and identifying physical and biological indicators of hydrologic regime. The Headwater Intermittent Streams Study is sponsored by eight U.S. Environmental Protection Agency (U.S. EPA) regions (Regions 1, 2, 3, 4, 5, 8, 9, and 10). We conducted a pilot study in 20032004 in four forests near Cincinnati (in cooperation with the U.S. Forest Service, state of Kentucky, and The Nature Conservancy) to develop field protocols and hydrologic indicators. In 2004, we held field workshops to train regional and state biologists and expanded the study to include forests in five of the U.S. EPA regions (1, 2, 3, 5, and 10). The goal of this additional research is to assess the applicability of methods and indicators outside of the pilot study area. Collaboration between the ORD and the U.S. EPA regions is well suited for the widespread and variable nature of headwater stream ecosystems. This collaborative effort will produce scientifically sound protocols for assessing conditions for the majority of streams and stream miles in the United States.

PRESENTATION Linking 'omic and Genetic Data to Physiologically-Based Pharmacokinetic and Pharmacodynamic Modeling to Enhance Ecological and Human Health Risk Assessment 05/16/2005
BENCIC, D. C., A. D. BIALES, R. W. FLICK, E. R. WAITS, TIM COLLETTE, D. GETER, M. OKINO, AND R. TORNERO-VELEZ. Linking 'omic and Genetic Data to Physiologically-Based Pharmacokinetic and Pharmacodynamic Modeling to Enhance Ecological and Human Health Risk Assessment. Presented at 2005 EPA Science Forum, Washington, DC, May 16 - 18, 2005.
Abstract: A great deal of academic, private sector, and government research has been initiated to apply advanced molecular biological methods to the discovery of toxicity pathways in wildlife and humans. One aim is the prediction of health outcomes based on the combination of refined chemical structure analysis with mechanistic data from systems biology studies. Quantitative ecological and human health risk assessments are expected to improve significantly. However, up to now, much less investment has been made in understanding the molecular mechanisms underlying the distribution, metabolism, and eventual excretion of stressors (i.e., pharmacokinetics and dose metrics).
A collaborative project across the U.S. Environmental Protection Agency (EPA)/ORD is being developed to use omic (genomic, proteomic, and metabolomic) and genetic technologies to provide data that would be directly incorporated into physiologically-based pharmacokinetic/pharmacodynamic (PBPK/PD) models. The approach for this project integrates expertise across ecological and human health research sciences. Molecular as well as tissue-level and whole organism endpoints will be measured to reveal dose phenomena in model aquatic organisms, the water flea Daphnia pulex (invertebrate), and the zebrafish Danio rerio (vertebrate) to a prototypical chemical. These models have been and are presently the focus of considerable genome sequencing efforts that the U.S. EPA/ORD can use as a resource. In addition, genetic technologies (measurement of DNA sequence polymorphisms) will provide an opportunity to study the extent to which variation in pharmacologic parameters can be explained by genetics. The combination of all techniques will allow us to identify and compare novel dose- and time-dependent indicators across multiple biological and taxonomic levels while simultaneously critically evaluating the relevance and linkage of biological data generated from multiple experimental platforms. Integration of U.S. EPA/ORD bioinformatics capabilities with those of dose modelers has the potential to reduce the uncertainty in the exposure component of both ecological and human health risk assessments. Partnered with other researchers within the ORDs Computational Toxicology Program, this project has the additional potential of forming linkages across a considerable portion of the source-to-outcome continuum that is within the purview of the U.S. EPAs risk assessment mission.

PRESENTATION Comparison of Random Site Selection at Multiple Intensities for the Assessment of the Ohio River Fish Community 05/16/2005
EMERY, E., K. A. BLOCKSOM, T. OLSEN, AND F. BORSUK. Comparison of Random Site Selection at Multiple Intensities for the Assessment of the Ohio River Fish Community. Presented at 2005 EPA Science Forum, Washington, DC, May 16 - 18, 2005.
Abstract: The Ohio River Valley Sanitation Commission (ORSANCO) is a compact of eight states representing interests in the Ohio River basin that has been instrumental in the development of biological monitoring of the Ohio River. In the past, ORSANCO has conducted intensive surveys by sampling every few miles along the Ohio River to estimate the condition of biological resources. These surveys were time-consuming and possibly represented an excessive effort in order to estimate condition. This study investigated the applicability of a random site selection approach as a means of assessing the structure, quality, attributes, and health of the fish assemblage in the Ohio River mainstem. A random site selection approach allows for assessment of conditions with known confidence while also reducing sampling effort. Randomized site selection was provided by the ORD-NHEERL, fish sampling was conducted by ORSANCO, and the ORD-NERL was responsible for analyzing data. However, work with U.S. EPA Region 3 was instrumental in recognizing the need for the study and providing Regionally Applied Research Effort (RARE) funding for the work. As a testament to the importance of this collaboration, in the future, ORSANCO will be using random site selection for conducting biological assessments to make the most efficient use of its resources.

PRESENTATION Advancing EPA Wetland Science: Developing Tools for Quantitative Assessment of Wetland Function and Condition at the Regional Level 05/16/2005
LANE, C. R. Advancing EPA Wetland Science: Developing Tools for Quantitative Assessment of Wetland Function and Condition at the Regional Level. Presented at 2005 EPA Science Forum, Washington, DC, May 16 - 18, 2005.
Abstract: The EPA Office of Water has recognized a critical need for tribes, states and federal agencies to be able to quantitatively assess the condition of the nations wetland resources. Currently, greater than 85% of states, tribes, and territories are lacking even rudimentary biological assessment methodologies for wetlands. Additional important needs identified include obtaining baseline nutrient and physical/chemical conditions to aid in understanding the role of wetland systems (isolated wetlands in particular) in ensuring aquatic life and beneficial uses of lakes, rivers, and streams in the watershed.
To address these challenges, we have initiated a pilot study with EPA Region IV to: 1) Develop a probabilistic sampling design that stratifies wetlands by type and size (also targeting reference conditions); 2) Collect biotic (macroinvertebrates, macrophytes, and diatoms) and abiotic (water and soil chemistry) data to establish baseline conditions, develop soil spectral database, and quantify wetland contribution to landscape nutrient dynamics; 3) Concurrently assess wetland condition with Level 1 (GIS) and Level 2 (rapid assessment) assessment methods; 4) Correlate biotic signature to local and landscape assessments; 5) Report on the condition of systems across region and recommend assessment methods to states and tribes.

In addition, we are currently planning research to develop a spectral library for monitoring and assessment of wetlands of the Cuyahoga basin in Ohio using visual and near infrared spectrometry. In order to leverage resources, the work involves collaboration with key personnel from Kenyon College and the Ohio Environmental Protection Agency, with sample processing and library development by the Wetland Biogeochemistry Lab at the University of Florida.

This research will provide a region-wide understanding of wetland condition and contribution to landscape nutrient dynamics. This will contribute to a fuller understanding of not only wetland condition, but also the use of wetlands in restoration, and the functions and benefits of wetlands with respect to regional environmental health.

PRESENTATION Fathead Minnow and Pearl Dace Pilot at Canadian Experimental Lakes Area 05/16/2005
LAZORCHAK, J. M., R. W. FLICK, K. KIDD, V. PALACE, AND R. EVANS. Fathead Minnow and Pearl Dace Pilot at Canadian Experimental Lakes Area. Presented at 2005 EPA Science Forum, Washington, DC, May 16 - 18, 2005.
Abstract: There is increasing concern about the potential impact of EDCs on aquatic organisms. Among the EDCs found in aquatic habitats are synthetic estrogens, which are used in contraceptives and other pharmaceuticals. These chemicals enter waterways through sewage treatment plants and septic systems and are also found in surface waters. EE2 is one of the most commonly used synthetic estrogens. Several studies have found EE2 in waters downstream of sewage treatment plants. In these rivers, concentrations of EE2 in the low ng/L levels are common, with some sites having concentrations as high as 40-60 ng/L.
A whole-lake endocrine-disruption experiment was conducted by Fisheries and Oceans Canada at the Experimental Lakes Area (ELA) in northwestern Ontario for three years beginning in 2001. This experiment examined population, organismal, biochemical, and cellular-level effects in lake trout, white sucker, fathead minnow, and pearl dace exposed to environmentally relevant (46 ng/L) concentrations of the synthetic estrogen, EE2. The U.S. Environmental Protection Agency (U.S EPA) collaborated in this study by evaluating VTG gene expression in (1) indigenous fathead minnows and pearl dace collected from the dosed and control lakes in 2001 through 2003, before and after dosing; (2) indigenous minnows collected in 2001from the control lake and deployed for 1, 3, 7, and 13 days in the dosed and control lakes; and (3) Cincinnati-cultured minnows exposed to water collected in 2001 through 2004 from ELA lakes and shipped to Cincinnati. In addition to water exposures, embryolarval fish and adult male fathead minnows were exposed to control- and dosed-lake whole sediment and sediment elutriate samples.

Methods developed to measure VTG gene expression in fathead minnows were validated for use in another cyprinid, pearl dace. Indigenous male fathead minnows and pearl dace collected at all time intervals from the dosed lake showed a constant level of elevation in VTG gene expression. Gene expression in the 2001 fathead minnow deployment study was detected within 24 hours after deployment of control fish into the treated lake and stayed elevated for the entire 13-day study. Highly variable gene expression was found in fathead minnow fry exposed to dosed-lake sediment elutriates, but no significant gene expression was found in fry exposed to control-lake sediment elutriates. Male adult fathead minnows exposed to sediment elutriates from sediments collected in 2004 in the previously dosed lake showed significant VTG gene expression. Results indicate that Real Time Polymerase Chain Reaction (RT-PCR) analyses of total RNA can be used to provide a rapid and timely estimate of exposure to estrogenic substances to indigenous organisms and in laboratory animals exposed to water and sediment samples. Furthermore, gene expression results, in combination with biochemical, histological, and chemical information, show that indigenous fathead minnows and pearl dace continuously exposed to 5 ng/L of EE2 will have adverse exposures.

Impacts and Outcomes

An EDC multiyear plan, "Annual Performance Measure," has been prepared and will be distributed to the Office of Water and regional offices to support the development of environmental policy and water quality criteria and standards development. A manuscript will also be prepared and submitted. Overall, this pilot research activity extended the capabilities of the U.S. EPA/ORD EDC monitoring efforts to a successful collaboration on an international whole-lake ecosystem study at an extremely remote location.

PRESENTATION Molecular Genetic Tools for Assessing the Status and Vulnerability of Aquatic Resources 05/16/2005
BAGLEY, M., M. J. BLUM, S. E. FRANSON, E. HEKKALA, S. A. JACKSON, AND E. R. WAITS. Molecular Genetic Tools for Assessing the Status and Vulnerability of Aquatic Resources. Presented at 2005 EPA Science Forum, Washington, DC, May 16 - 18, 2005.
Abstract: Development of ecological indicators that efficiently capture the present condition and project future vulnerabilities of biological resources is critical to sound environmental management. For this reason, the ORD's Ecological Research Program is developing genetic methodologies to supplement and improve existing ecological indicators for aquatic ecosystems. Five research areas that can potentially improve the science of ecological assessment through incorporation of genetic methods are under active investigation: (1) development of accurate and precise methods for biological identification of aquatic species and subspecies, (2) delineation of ecological assessment units through analysis of genetic structure across multiple species, (3) assessment of changes in genetic diversity as an indicator of present and historical environmental condition, (4) assessment of genetic diversity at diagnostic loci and across the genome as an indicator of vulnerability to future environmental perturbations, and (5) integrated assessments to link landscape-level stressors to population-level outcomes. A number of these research applications were recently explored in the Mid-Atlantic Integrated Assessment (MAIA) area. Molecular genetic analysis documented that species identification based on morphological analysis in the field was reasonably accurate. However, for two of three fish species assessed across the MAIA region, genetic analysis revealed highly distinct groups that likely represent undescribed species or subspecies. Geographic correspondence of genetic structure across these species suggested that genetics could be used to refine biogeographic boundaries. Each of the fish species displayed characteristic associations between genetic diversity and various environmental parameters. Ongoing work on invasive species utilizes "DNA taxonomy" for identifying morphologically indistinct organisms in ballast water and recipient waters as well as for documenting rates of introgressive hybridization between invading and resident stream fish. Ongoing collaborative research in landscape ecology, genetics, and population modeling is aimed at addressing questions of resource vulnerability and design of integrated ecological assessments. Ultimately, this work will produce highly effective tools that the states, tribes, and U.S. Environmental Protection Agency (U.S. EPA) regions will be able to implement for assessing and protecting the aquatic biodiversity.

PRESENTATION Using Genomic Indicators in Aquatic Organisms to Manage Stream Populations Exposed to Emerging Chemicals 04/22/2005
LAZORCHAK, J. M., A. D. BIALES, B. R. JOHNSON, K. A. BLOCKSOM, J. E. FLOTEMERSCH, AND E. EMERY. Using Genomic Indicators in Aquatic Organisms to Manage Stream Populations Exposed to Emerging Chemicals. Presented at Wright State University, Dayton, OH, April 22, 2005.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Assessing the Transitional Waters Between Wadeable Streams and Boatable Rivers 03/25/2005
FLOTEMERSCH, J. E., L. REYNOLDS, F. BORSUK, M. PASSMORE, AND G. POND. Assessing the Transitional Waters Between Wadeable Streams and Boatable Rivers. Presented at Mid-Atlantic Aquatic Biologists Workshop, Berkeley Springs, WV, March 24 - 25, 2005.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Factors Controlling the Hydrologic Permanence of Headwater Streams 03/25/2005
FRITZ, K. M., B. R. JOHNSON, AND DAVID M. WALTERS. Factors Controlling the Hydrologic Permanence of Headwater Streams. Presented at Mid-Atlantic Aquatic Biologists Workshop, Berkeley Springs, WV, March 24 - 25, 2005.
Abstract: Headwater streams are vital linkages between upland land use/cover and downstream water bodies. They are prone to natural drying, which confounds our ability to use traditional assessment tools. Recognizing the hydrologic permanence (duration and frequency of flowing conditions) of headwater streams is the critical first step in condition assessment. Our objective is to identify physical characteristics that are indicators of the headwater stream permanence.

PRESENTATION Development of Large River Bioassessment Protocols (Lr-Bp) for Benthic Macroinvertebrates in EPA Region 5 03/24/2005
JOHNSON, B. R., K. A. BLOCKSOM, AND J. E. FLOTEMERSCH. Development of Large River Bioassessment Protocols (Lr-Bp) for Benthic Macroinvertebrates in EPA Region 5. Presented at Mid-Atlantic Aquatic Biologists Workshop, Berkeley Springs, WV, March 24 - 25, 2005.
Abstract: Since passage of the Clean Water Act, government agencies have made extensive use of biomonitoring protocols to report on the quality of wadeable streams and rivers. Non-wadeable systems have been largely overlooked because of
sampling difficulties and a lack of appropriate methods and biological indicators. Yet large rivers are critical natural, commercial, and aesthetic resources, and the need for assessment has risen along with increasing awareness of

cumulative stressor effects and observed degradation in coastal zones. Development of standardized sampling methods and identification of appropriate indicators is the first step towards developing biocriteria for these vital resources.

PRESENTATION Identifying the Causes of Biological Impairment in Streams: the Causal Analysis/Diagnosis Decision Information System (Caddis) 03/08/2005
CORMIER, S. M. Identifying the Causes of Biological Impairment in Streams: the Causal Analysis/Diagnosis Decision Information System (Caddis). Presented at State and EPA Meeting on Water Quality Standards, Washington, DC, March 08 - 09, 2005.
Abstract: The causal analysis/diagnosis decision information system (CADDIS) is being developed by EPA's Office of Research and Development and Office of Water to assist states and tribes in identifying unknown causes of biological impairment of the nation's waterbodies. This will be a valuable system for monitoring, TMDL, permitting and other key water programs. The CADDIS system is being constructed in phases. CADDIS I, which is now available for trial use, is a user-friendly web-based system that helps states and tribes walk through the stressor identification process developed by ORD in 2000. Close to a dozen states are now using this procedure. CADDIS II will be an expansion of the system that will provide a literature database on stressor-response relationships, case studies of successful state and tribal stressor identifications and models of these successful efforts that other states can use in new situations. Attendees will have an opportunity to provide input on DADDIS II design.

PRESENTATION Bioassessment Methods Comparability Research in Streams and Rivers 03/08/2005
BLOCKSOM, K. A. Bioassessment Methods Comparability Research in Streams and Rivers. Presented at Methods and Data Comparability Board Meeting, St. Petersburg, FL, March 08, 2005.
Abstract: Comparison of different sampling methods used to collect macroinvertebrates in wadeable streams and large rivers, using single and multiple habitat approach.

PRESENTATION Altered Gene Expression and Development of Potential Biomarkers in Medaka (Oryzias Latipes) Brain, Liver and Testis Following Exposure to Fibrate Pharmaceuticals 03/07/2005
Bencic, D C., D. C. Volz, P. Chen, A Biales, J M. Lazorchak, D. E. Hinton, AND S. W. Kullman. Altered Gene Expression and Development of Potential Biomarkers in Medaka (Oryzias Latipes) Brain, Liver and Testis Following Exposure to Fibrate Pharmaceuticals. Presented at Society of Toxicology, New Orleans, LA, March 06 - 10, 2005.
Abstract: To help address the consequences of increasing levels of environmental contaminants and to identify potentially novel markers of toxicity, we examined gene expression profiles from medaka (Oryzias latipes) exposed to a prototypical fibrate pharmaceutical. Changes in gene expression in male medaka brain, liver and testis following 48 h exposure to 15 ug (injected) of the antihyperlipidemic agent ciprofibrate (CF) were analyzed using suppressive subtractive hydridization. From a total of 1152 clones, 288 were sequenced and 100 were identified as differentially expressed. Furthermore, only one gene was shared among all three organs and less than 5% between any two organs, suggesting organ specific responses at the level of gene expression. The results of this CF and other xenobiotic induced gene expression studies were used to develop macroarrays specific for brain, liver or testis containing 200-300 non-redundant cDNAs. Following 7 day water exposures to 10, 100 and 1000 ug/l of CF or clofibrate, compound, dose and organ specific altered gene expression was determined. Highly responsive genes were further validated using real-time QPCR. In order to associate changes in gene expression with altered phenotype, compound- and dose-dependent histopathology samples were also examined. A combination of macroarray, real-time QPCR and histopathological techniques will aid in linking molecular events and biochemical alterations following exposure and provide a mechanism to evaluate exposure and effects at the individual and population levels.

PRESENTATION A Cross-Species Approach to Using Genomics Tools in Aquatic Toxicology 03/07/2005
Miracle, A L., I Knoebl, D Bencic, D L. Lattier, R Wang, D. Villeneuve, G Ankley, D. H. MILLER, J. F. KENNEKE, D. R. EKMAN, T. WHITEHEAD, AND K. WATANABE. A Cross-Species Approach to Using Genomics Tools in Aquatic Toxicology. Presented at Society of Toxicology, New Orleans, LA, March 06 - 10, 2005.
Abstract: Microarray technology has proven to be a useful tool for analyzing the transcriptome of various organisms representing conditions such as disease states, developmental stages, and responses to chemical exposure. Most commercially available arrays are limited to organisms that have complete, or near complete, genome information, few of which are relevant for non-mammalian toxicology. However, with the imminent completion of the zebrafish genome project, and the availability of high-density microarrays, the zebrafish (Danio rerio) represents a useful species for focused toxicological research. An approach involving the transcriptional mining of the zebrafish for potential biomarkers to be validated for use in another cyprinid, the fathead minnow (Pimephales promelas), will be described as a useful cross-species comparison for using genomics in an organism without a defined genome. The high degree of evolutionary conservation in vertebrates of many biochemical and developmental pathways strongly supports the extrapolation of molecular data from one fish species to another. Linkage of other molecular measures and phenotypic effects are also required to interpret transcriptional comparisons between the species.

PRESENTATION Regional Methods Initiative: Development of Large River Bioassessment Protocols (Lrbp) for Benthic Macroinvertebrates 02/02/2005
JOHNSON, B. R., J. E. FLOTEMERSCH, AND K. A. BLOCKSOM. Regional Methods Initiative: Development of Large River Bioassessment Protocols (Lrbp) for Benthic Macroinvertebrates. Presented at SWIMS Conference, Chicago, IL, February 01 - 03, 2005.
Abstract: We are developing the Large River Bioassessment Protocol (LRBP) for assessment of benthic macroinvertebrate assemblages. This multi-habitat method is currently being used in support of a REMAP project for probabilistic assessment of large rivers in USEPA Region 5. Six rivers, representing a gradient of size and landuse, were targeted for sampling in summer 2004 and 2005. On each river, we are collecting macroinvertebrates, water chemistry, phytoplankton, and habitat data from 25 sites. Results will be used to identify potential benthic and habitat indicators for the region and to refine LRBP habitat assessment methods. This study will also compare the LRBP with other sampling methods used by States and will evaluate the use of snag sampling as a rapid bioreconnaissance tool. In this presentation, we will provide a detailed description of the LRBP method and an update on project status.

PRESENTATION Regional Methods Initiative: Development of Biological Indicators, Methods and Assessment Techniques in First Order and Intermittent Streams: Headwater Intermittent Streams Study 02/02/2005
FRITZ, K. M., B. R. JOHNSON, J. GREENWOOD, AND DAVID M. WALTERS. Regional Methods Initiative: Development of Biological Indicators, Methods and Assessment Techniques in First Order and Intermittent Streams: Headwater Intermittent Streams Study. Presented at SWIMS Conference, Chicago, IL, February 01 - 03, 2005.
Abstract: Headwater streams represent the majority of streams and stream miles within many stream networks. Because headwater streams represent the interface between surrounding land use and downstream waterbodies, there has been a growing interest in monitoring the condition of headwater streams. However, because of their position in the landscape, many headwater streams are prone to natural drying and, therefore, confound traditional assessment tools. Our primary objectives are to 1) develop assessment methods specifically designed for headwater streams, and 2) identify physical and biological characteristics of headwater reaches that are indicative of hydrologic permanence and therefore useful in stream assessments. The initial part of the study surveyed 61 reaches along 17 headwater streams across four forests in Indiana, Kentucky and Ohio that varied in hydrologic permanence over the 2-year study. The study was expanded to include additional sites in Regions 1, 2, 3, 5 and 10. We will provide an update of the study and physical and biological results from the initial survey.

PUBLISHED REPORT Field and Laboratory Performance Characteristics of a New Sampling Method for Riverine Macroinvertebrate Assemblages 09/30/2005
BLOCKSOM, K. A. AND J. E. FLOTEMERSCH. Field and Laboratory Performance Characteristics of a New Sampling Method for Riverine Macroinvertebrate Assemblages. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-05/097 (NTIS PB2006-114612), 2005.
Abstract: This document describes the approach and results of a study to measure the performance characteristics of a macroinvertebrate sampling protocol recently developed for nonwadeable streams and rivers. The findings in this report will assist monitoring agencies by providing performance information not typically available with bioassessment methods.

 

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