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Ecological Exposure Research Division Publications: 2001
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This page lists publication titles, citations and abstracts produced by NERL's Ecological Exposure Research Division for the year 2001, organized by Publication Type. Your search has returned
44 Matching Entries.
See also Ecological Exposure Research Division citations with abstracts:
1999,
2000,
2001,
2002,
2003,
2004,
2005,
2006,
2007,
2008
Technical Information Manager: Linda Ransick - (513) 569-7395 or ransick.linda@epa.gov
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Presented/Published |
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Historical Monitoring of Biomarkers of PAH Exposure of Brown Bullhead in the Remediated Black River and the Cuyahoga River, Ohio |
05/01/2001
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Lin, E. C., T. W. Neiheisel, J. E. Flotemersch, B. Subramanian, D. E. Williams, M. R. Millward, AND S. M. Cormier. Historical Monitoring of Biomarkers of PAH Exposure of Brown Bullhead in the Remediated Black River and the Cuyahoga River, Ohio. JOURNAL OF GREAT LAKES RESEARCH 27(2):191-198, (2001).
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Biomarkers of exposure to chemical contamination were measured in brown bullhead from a heavily PAH contaminated section of the Black River, Ohio, during and immediately after remedial sediment dredging in 1990-1991, and in follow-up visits in 1993 and 1998. Biomarker levels of bullhead from the historically polluted Cuyahoga River and the protected Old Woman Creek National Estuarine Sanctuary were also measured over the same periods. PAH bile metabolite concentrations of bullheads from the Black River were still elevated in the year following dredging, but were significantly lower in the later resampling years. Metabolite concentrations of Cuyahoga River bullhead decreased significantly between 1991 and 1993, possibly in response to the shutdown of coking operations on the river. Fish from the Old Woman Creek site showed some viaration in metabolie levels among periods, but were consistently lower than the other two rivers at each time. Measurement of bile metabolites proved an effective tool for estimating changes in exposure over time and among sampling sites. Trends in biomarkers indicated lowered exposures in the Black River, probably as a result of remediation, and in the Cuyahoga, probably as a result of source reduction and incidental sediment displacement.
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| JOURNAL |
Vitellogenin Gene Transcription: A Relative Quantitative Exposure Indicator of Environmental Estrogens |
09/01/2001
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Lattier, D. L., D. A. Gordon, D. J. Burks, AND G. P. Toth. Vitellogenin Gene Transcription: A Relative Quantitative Exposure Indicator of Environmental Estrogens. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 20(9):1979-1985, (2001).
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We report the development of a quantifiable exposure indicator for measuring the presence of environmental estrogens in aquatic systems. Synthetic oligonucleotides, designed specifically for the vitellogenin gene (Vg) transcription product, were used in a Reverse Transcription Polymerase Chain Reaction (RT-PCR) protocol. This extremely sensitive and rapid method was able to detect vitellogenin gene transcription in male common carp (Cyprinus carpio) injected with 17B-estradiol. Sequence analysis of the induced rRNA product confirmed a vitellogenin gene transcirpt with homology to rainbow trout and fathead minnow vitellogenin cDNA sequences. Relative levels of vitellogenin gene induction among individuals were quantified by incorporating 18S rRNA 'universal' primers and Competimers in a PCR "multiplex" reaction with primers for vitellogenin. This method is more sensitive than current protocols, such as mortality, visible signs of stress, or other techniques which look for unscheduled gene expression, since we measure the appearance of primary transcripts at the nanogram level. In addition, this procedure does not sacrifice accuracy or reliability even though the exposure to estrogen is within one day. This research will support the construction of regional stressor profiles, thereby providing a method for comparative enviornmental exposure assessment. It may also provide an in vivo screening method for potential endocrine disrupting compounds.
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| JOURNAL |
Home Range and Habitat Use of Suburban Red-Shouldered Hawks in Southwestern Ohio |
09/01/2001
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Dykstra, C. R., J. L. Hays, F. B. Daniel, AND M. M. Simon. Home Range and Habitat Use of Suburban Red-Shouldered Hawks in Southwestern Ohio. WILSON BULLETIN 113(3):308-316, (2001).
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Suburban habitats may provide different resources and different challenges to raptors than do more traditional, rural habitats. Suburban red-shouldered hawks (Buteo lineatus) of the eastern subspecies have been little studied. We measured the home ranges and habitat use of 11 suburban red-shouldered hawks during the breeding season, and 9 hawks during the non-breeding season, using standard telemetry techniques. Home ranges, calculated using the adaptive kernel method (95% isopleth), averaged 90 +/- 11 ha for breeding season, 189 +/- 33 ha for non-breeding season, and 165 +/- 24 ha for the year-round home range. Males and females did not differ in home range size. Habitat use by hawks was determined by classifying habitat where birds were observed perching. Habitat use differed from habitat available within home ranges for all birds tested (P < 0.05). Most red-shouldered hawks used riparian zones and pond edges more than would be expected, based on availability of such habitat within their home ranges; residential areas and lawns were used less than expected or in proportion to their availability. Suburban red-shouldered hawks demonstrated significant use of human-altered habitats, as well as tolerance of human disturbance.
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| JOURNAL |
Chronic Toxicity of 1,3,5-Trinitrobenzene in Fischer 344 Rats |
02/01/2001
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Reddy, T. V., G. R. Olson, B. E. Wiechman, G. Reddy, J. A. Torsella, F. B. Daniel, AND G. J. Leach. Chronic Toxicity of 1,3,5-Trinitrobenzene in Fischer 344 Rats. INTERNATIONAL JOURNAL OF TOXICOLOGY 20(2):59-67, (2001).
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The chronic toxicity of 1,3,5-trinitrobenzene (TNB) in male and female Fischer 344 (F344) rats was evaluated by feeding a diet containing 0, 5, 60 and 300 ppm of TNB for 2 years. The calculated average TNB intake over 2 years for males and females was 0.22, 2.64, 13.44 and 0.23, 2.68, 13.31 mg/kg body weight (BW)/day respectively. Terminal body weights were decreased and water intake was increased in both sexes (300 ppm), whereas food consumption was decreased in males (60 and 300 ppm groups) only. The relative spleen weights were significantly decreased in both sexes (300 ppm), whereas the relative brain weights were increased in females only (300 ppm). Hematological effects were not observed in animals killed at the 2-year time point, except significant decrease in the mean corpuscular hemoglobin (MCH) in males (300 ppm) and in females (60 and 300 ppm). Methemoglobin levels were increased in both sexes in the high dose group. Histopathological examination showed treatment-related changes in the kidney (hyaline droplets; 60 and 300 ppm) and the spleen (erythroid cell hyperplasia and pigment deposition; 300 ppm) of both sexes. Cytoplasmic hyaline droplets in the kidneys were characterized by immunohistochemistry as alpha-2u-globulin. We propose a chronic, oral no-observable-adverse-effect level (NOAEL) of 2.68 mg/kg BW/day for TNB in the rat, based on the hematological and renal changes.
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| JOURNAL |
Method-Specific Precision and Bias Relationships Developed from Data Submitted During USEPA Drinking Water Laboratory Performance Evaluation Studies |
01/01/2001
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Britton, P. W. Method-Specific Precision and Bias Relationships Developed from Data Submitted During USEPA Drinking Water Laboratory Performance Evaluation Studies. JOURNAL OF TESTING AND EVALUATION (ASTM) 29(1):79-112, (2001).
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This paper documents the process used by the United States Environmental Protection Agency (USEPA) to estimate the mean and standard deviation of data reported by in-control drinking water laboratories during Water Supply (WS) studies. This process is then applied to the data reported for each specific sample, analyte, and method in ten WS studies, and linear relationships between the mean response and true analyte concentration and between the interlaboratory standard deviation of responses and true analyte concentraton are presented. Such relationships can be invaluable as background information for anyone who must conduct an interlaboratory study using the same methods to analyze similar interference-free samples or who must evaluate the analytical quality of such data.
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| JOURNAL |
Development of An Index of Biotic Integrity for the Mid-Atlantic Highlands Region |
06/01/2001
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McCormick, F. H., R. M. Hughes, P. R. Kaufmann, D. V. Peck, J. L. Stoddard, AND A. T. Herlihy. Development of An Index of Biotic Integrity for the Mid-Atlantic Highlands Region. TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY 130(5):857-877, (2001).
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From 1993 to 1996, fish assemblage data were collected from 309 wadeable streams in the U.S. Mid-Atlantic Highlands region as part of the U.S. Environmental Protection Agency's Environmental Monitoring and Assessment Program. Stream sites were selected with a probabilistic sampling design that allowed regional estimates of stream condition. We examined responses of 58 fish assemblage metrics to physical, chemical, and landscape indicators of disturbance. Univariate and multivariate analyses of relationships among fish metrics, habitat integrity, and anthropogenic disturbance were used to develop a fish index of biotic integrity (IBI) for assessing stream condition in the entire region. Of 58 candidate metrics, nine were selected and scored continuously from 0 to 10; the resulting IBI was scaled so that it ranged from 0 to 100. Regional estimates of stream conditions showed that 27% of the stream length in the Mid-Atlantic Highlands had fish assemblages in good or excellent ecological condition. Of the total wadeable perennial stream length in the region, 38% was fair and 14% was poor. There were insufficient data to calculate IBIs for 21% of the wadeable stream length in the Mid-Atlantic Highlands; all of these streams were small and lacked sufficient sample size (<10 individuals) to calculate an IBI.
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Analysis of Macroinvertebrate Assemblages in Relation to Environmental Gradients in Rocky Mountain Streams |
06/01/2001
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Griffith, M. B., P. R. Kaufmann, A. T. Herlihy, AND B. H. Hill. Analysis of Macroinvertebrate Assemblages in Relation to Environmental Gradients in Rocky Mountain Streams. ECOLOGICAL APPLICATIONS 11(2):489-505, (2001).
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Using redundancy analysis (RDA) and canonical correspondence analysis (CCA), we assessed relationships among chemical and physical characteristics and macroinvertebrate assemblages at stream sites sampled by the Regional Environmental Monitoring and Assessment Program (R-EMAP) in the mineral belt of the Southern Rockies Ecoregion in Colorado. We contrasted results of analyses where community structure was summarized as community metrics and analyses based on genera abundances. Our objective was to identify metrics or taxa diagnostic of major environmental stressors in these streams. When RDA was used to analyze the community metrics data, three axes were significant, accounting for 96% of the metric- environment relation. The first RDA axis was correlated with dissolved cadmium, sediment zinc, and total suspended solids, variables that indicate it was related to mining effects. The second and third RDA axes were correlated with water temperature, mean substrate embeddedness, mean canopy density at the banks, and a riparian human disturbance index for agriculture, variables associated with riparian and substrate alterations associated with grazing by livestock. When CCA was used to analyze the genera abundance data, four axes were significant, accounting for 45% of the species-environment relation. The CCA axes were correlated with total and dissolved iron, water temperature, dissolved and total organic carbon, mean bank height, and mean water surface gradient, variables associated with riparian disturbance from livestock grazing, but not with mining effects. Because CCA measures variation in community structure in terms of changes in the absolute abundances of different genera relative to one another, that analysis of genera abundances was sensitive to the effects of riparian disturbance and stream size, but not to the general toxicological effects associated with mining that reduced the abundances of all genera. Community metrics measure various aspects of community structure, including taxa richness, taxa relative abundances, and taxa relative dominance, and these metrics were sensitive to the effects of mining, riparian disturbance, and stream size. Some community metrics, such as the percentage abundance of the most dominant taxon, the total number of individuals, the total number of taxa, and the number of chironomid taxa, may be used to diagnose the environmental stressors in these streams, while the results of the CCA for genera abundances may be used to design new metrics for this purpose.
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| JOURNAL |
Correlation of Red-Shouldered Hawk Abundance and Macrohabitat Characteristics in Southern Ohio |
08/01/2001
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Dykstra, C. R., F. B. Daniel, J. L. Hays, AND M. M. Simon. Correlation of Red-Shouldered Hawk Abundance and Macrohabitat Characteristics in Southern Ohio. CONDOR 103(3):652-656, (2001).
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We measured an index of Red-shouldered Hawk (Buteo lineatus) abundance along streams in southern Ohio and related differences in abundance index to landscape scale habitat characteristics within the surveyed areas. Fifteen study sites, each a 5.8-km reach of permanent stream, were surveyed four times using broadcasts of Red-shouldered Hawk calls and Red-tailed Hawk (Buteo jamaicensis) calls. We determined the landcover types in a corridor surrounding each surveyed area using a GIS landcover data grid, and counted the number of small ponds within each corridor. We calculated hawk response rate for each species as the mean number of visual or aural detections per survey. Red-shouldered Hawk response rate was inversely correlated to Red-tailed Hawk response rate (r = -0.52, P < 0.04), and was positively correlated to the number of small ponds within each stream corridor (r = 0.77, P < 0.01), suggesting that the number of small ponds was important factor associated with Red-shouldered Hawk abundance.
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| NEWSLETTER |
Leeches (Class Hirudinea, Subclass Euhirudinea) of the Great Smoky Mountains National Park |
10/01/2001
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Moser, W. E. AND D. J. Klemm. Leeches (Class Hirudinea, Subclass Euhirudinea) of the Great Smoky Mountains National Park. Discover Life in America, Gatlinburg, TN, (4), 2001.
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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.
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| PRESENTATION |
A Toxicity Assessment Approach to Evaluating in-Situ Bioremediation of PAH Contaminated Sediments |
06/04/2001
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Lazorchak, J. M., M. E. Smith, AND H. H. Tabak. A Toxicity Assessment Approach to Evaluating in-Situ Bioremediation of PAH Contaminated Sediments. Presented at 6th International Symposium: In-Situ and On-Site Bioremediation, San Diego, CA, June 4-7, 2001.
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Freshwater and marine sediment toxicity tests were used to measure baseline toxicity of sediment samples collected from New Jersey/New York Harbor (NJ/NY) (non-PAH- contaminated) sediment (ERC). Four freshwater toxicity tests were used: 1) amphipod (Hyalella azteca) mortality and growth tests (a standard 10-day USEPA method and two 7-day exposure methods (one using the standard amount of sediment, 100 ml; one using a reduced sediment volume, 17 ml)-the reduced volume freshwater amphipod test was developed and used in this study since existing volume requirements of the USEPA standard method exceeded the amounts available from enhanced or natural attenuation treatment); 2) a 7-day aquatic worm (lumbriculus variegatus) mortality and budding test; 3) a 7/8-day fathead minnow (Pimephales promelas) embryo-larval survival and teratogenic test (FHM-EL); and 4) a 4-day vascular aquatic plant (Lemna minor) frond number/growth/chlorophyll a test (Duckweed). Two marine tests were also used: 1) amphipod (Ampelisca abdita) 10-day mortality test and a sheepshead minnow (Cyprinodon variegatus) embryo-larval sediment test (SHM-EL). ERC sediments were found to be highly toxic to all freshwater and marine organisms tested while the NJ/NY non-PAH contaminated sample showed no significant toxicity to the marine amphipod, but was slightly toxic to the freshwater worm and to freshwater and marine fish. For all tests run with freshwater organisms and the one marine amphipod no survival was found in any of the tests except for one of the freshwater amphipod tests (55%). The ERC sediment significantly reduced frond production (-58.3%) and chlorophyll a levels (-35.4%) in the freshwater duckweed test. To determine the cause of toxicity in the sediments, five sediment manipulations were performed: 1) a sediment purge procedure, where 2-4 volumes of lab water were replaced over the sediment in a 24-h period; 2) a sediment dilution procedure where grade 40 silica sand was mixed with PAH-contaminated sedments on a weight:weight basis; 3) a sediment aeration procedure where sediment samples were aerated by adding 80 ml of sediment (140 gms) to a 250 ml glass graduated cylinder and 120 ml of overlying water followed by aeration for 24-48h; 4) an Ambersorb Treatment Procedure, where PAH-contaminated sediment samples were treated with two types of organic removal resins - Ambersorb 563 and 572; and 5) an Amberlite Treatment Procedure where IRC-718, an inorganic removal resin was mixed with PAH-contaminated sediments. Results showed that freshwater amphipod survival was improved with the sediment aeration procedure and with 8% AS 563 and 572 treatments. Toxicity can also be reduced with the sediment dilution technique (100-fold). These manipulations revealed that hydrogen sulfide, organic compounds and inorganic compounds (metals) were factors in ERC sediment toxicity.
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| PRESENTATION |
Genetic Damage Indicators in Fish Exposed to Varying Stream Conditions in An Agricultural Watershed |
03/16/2001
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Meier, J. R., L. W. Chang, F. B. Daniel, S. E. Franson, AND P. A. Wernsing. Genetic Damage Indicators in Fish Exposed to Varying Stream Conditions in An Agricultural Watershed. Presented at Environmental Mutagen Society, San Diego, CA, March 16-21, 2001.
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Micronucleus (MN) and single cell gel electrophoresis (SCG) measures of genetic damage in fish erythrocytes were included in an evaluation of a wide range of biological and physical stream condition parameters being developed for use in watershed and regional scale assessments. Bluegill sunfish (BG; Lepomis macrochirus) and white suckers (WS; Catostomus commersoni) were selected as target species because of their abundance in Midwestern streams and their differing exposures to contaminants in the water column and sediment, respectively. Fish were collected by electroshocking from 11 headwater tributaries of the Little Miami River watershed in southwestern Ohio. All streams were set in a predominantly agricultural landscape but showed a range of landcover metrics, water chemistry conditions and in-stream habitat measures. For the SCG assay, the tail length, tail moment and % tail DNA parameters were analyzed by computerized image analysis. For the MN assay, acridine orange-stained blood smears were scored manually for micronuclei in polychromatic erythrocytes (PCE) and normochromatic erythrocytes (NCE). MN frequencies in BG from all locations were very low (less than 0.1 MN/1,000 PCEs or NCEs) and comparable to values for laboratory maintained fish. Values for WS ranged from 0 to 0.4 MN/1,000 NCEs. The MN levels in WS appeared to correlate with varying rates of erythrocyte turnover (PCE:NCE ratio) in fish collected from different sites. The SCG parameters in BG were also comparable to laboratory control values, and did not vary significantly among sites for either species. Preliminary results indicate that the levels of genetic damage observed were not correlated with the range of conditions (water chemistry, land cover, etc.) observed in these streams.
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| PRESENTATION |
Comparative Application of Periphyton, Macroinvertebrate and Fish Indices of Biotic Integrity to Southern Rocky Mountain Streams |
06/03/2001
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Griffith, M. B., B. H. Hill, F. H. McCormick, P. R. Kaufmann, AND A. T. Herlihy. Comparative Application of Periphyton, Macroinvertebrate and Fish Indices of Biotic Integrity to Southern Rocky Mountain Streams. Presented at North American Benthological Society, LaCrosse, WI, June 3-8, 2001.
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We compared three assessments using macroinvertebrate, periphyton, and fish assemblages in streams sampled by the Regional Environmental Monitoring and Assessment Program (REMAP) in Colorado's Southern Rockies Ecoregion. We contrasted analyses using metrics for each group selected to be diagnostic of stressors in these streams and, for macroinvertebrates and periphyton, to create an Index of Biotic Integrity. Principle components analysis (PCA) of ten macroinvertebrate metrics separated three axes correlated with sediment metals, with dissolved metals, and with riparian disturbance and sediment embeddedness. PCA of five fish metrics separated three axes correlated with sediment coarseness, riparian shading, suspended solids, SO4, and dissolved metals, with sediment metals, and with stream width and depth. PCA of ten periphyton metrics separated three axes correlated with dissolved and sediment metals, with sediment coarseness, and with riparian structure, sediment embeddedness, and PO4. The first two axes for macroinvertebrates and for fish and the first axis for periphyton were associated with mining effects. The third axis for macroinvertebrates and for periphyton were associated with agricultural effects. The third axis for fish and the second axis for periphyton were natural gradients. Metrics for each assemblage differed in sensitivity to the two major stressor gradients (i.e., mining and agriculture) and to natural gradients.
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| PRESENTATION |
Using the Stressor Identification Guidance to Identify the Cause of Degradation of the Benthic Invertebrate Community in the Presumpscot River, Maine |
06/03/2001
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Cormier, S. M., S. Davies, P. Mitnik, AND J. Gerritsen. Using the Stressor Identification Guidance to Identify the Cause of Degradation of the Benthic Invertebrate Community in the Presumpscot River, Maine. Presented at North American Benthological Society, La Crosse, WI, June 3-8, 2001.
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From 1984 to 1996, an impounded segment of the Presumpscot River, downstream of a major point source, failed to attain Maine's Class C aquatic life standards based on benthic invertebrate assemblages. Eight candidate causes were hypothesized: 1) toxic chemicals; 2) floc resulting in low dissolved oxygen (DO); 3) settleable floc causing smothering; 4) excess nutrients; 5) impoundment increasing sedimentation; 6) impoundment decreasing flow velocity; 7) impoundment causing low DO; and 8) impoundment causing habitat loss. All causes with low DO were eliminated because concentrations were adequate for maintenance of aquatic life above and below the discharge. Total phosphorus was elevated below the discharge but chlorophyll a concentrations were negligibly increased. A strength of evidence analysis identified the cause from among the remaining four. Toxic chemicals were unlikely due to low concentrations. The two impoundment hypotheses were unlikely because other hydraulically similar impoundments attained aquatic life standards; and an upstream site within the same impoundment met aquatic life use criteria. Evidence favored the floc hypothesis. The exposure pathway was complete and plausible. Other rivers with similar elevated floc had impaired biological assemblages. In another river, the Androscoggin, reductions in the discharge reduced the settled floc and the biological assemblage recovered. Floc was identified as the cause.
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| PRESENTATION |
Determination of Condition Categories for Biotic Indices Using Power Analysis |
06/03/2001
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Blocksom, K. A. AND F. A. Fulk. Determination of Condition Categories for Biotic Indices Using Power Analysis. Presented at North American Benthological Society, La Crosse, WI, June 3-8, 2001.
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Multimetric biotic indices are often used in bioassessment programs to determine the condition of water resources. These indices are typically divided into a number of condition tiers (e.g., good, poor). However, the number of tiers is often based on professional judgement. We used bootstrapping and Monte Carlo methods of power analysis to establish and compare the number of condition tiers defensible for a newly developed biotic index for the Mid-Atlantic highlands. Through power analysis, we calculated the effect size, the minimum difference in index scores necessary to correctly recognize that any two sites differ in condition. Dividing the range of the index by the effect of power anaysis, we calculated this effect size based on the empirical distribution of the data and required replicated samples. The Monte Carlo method relied on an assumed distribution and an estimate of variability to ascertain the effect size. Results from the Monte Carlo method were sensitive to both the estimate of variability and the sample size. However, this sensitivity decreased beyond a sample size of two per site.
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| PRESENTATION |
Development of a Method for Determining Phosphorus Nutrient Criteria in Streams and Rivers of the Mid-Atlantic Region |
06/03/2001
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Wang, N. AND S. M. Cormier. Development of a Method for Determining Phosphorus Nutrient Criteria in Streams and Rivers of the Mid-Atlantic Region. Presented at North American Benthological Society, La Crosse, WI, June 3-8, 2001.
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Nutrient enrichment of phosphorus and nitrogen is the second most cited cause for impairment of streams and rivers in the U.S. There is a need to develop stream nutrient criteria to control nutrient loadings. Since biotic metrics can assess the overall impact of nutrient enrichment to streams and rivers, they may provide a scientific basis for setting nutrient criteria. The overall objective of this study was to develop and compare methods, using biotic metrics, for determining target nutrient concentrations that protect the biotic integrity of the majority of streams from nutrient enrichment. Data from the U.S. EPA EMAP sampling program in the mid-Atlantic region was used. Relationships between biotic metrics and phosphorus concentrations in the streams and rivers were analyzed. EPT taxa (Ephemeroptera, Plecoptera, and Trichoptera) were found to be one of the most suitable biotic metrics sensitive to phosphorus enrichment. Reference sites that have little disturbance in biological communities from nutrient enrichment were then identified based on EPT taxa. For demonstration purposes, specific numeric nutrient target concentrations for rivers and streams in the mid-Atlantic region were developed and compared. The nutrient criteria developed are comparable to the threshold values for eutrophication found in the literature.
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| PRESENTATION |
Comparison of Two Macroinvertebrate Collection Methods for Bioassessment of Wadeable Streams |
06/04/2001
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Klemm, D. J., P. A. Lewis, W. T. Thoeny, AND F. A. Fulk. Comparison of Two Macroinvertebrate Collection Methods for Bioassessment of Wadeable Streams. Presented at North American Benthological Society, La Crosse, WI, June 3-8, 2001.
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The objective of this study was to compare the results of collecting and analyzing macroinvertebrate data using a composite versus a single sample method. It was conducted as part of the Environmental Monitoring and Assessment Program (EMAP) Indicator Development Project of the U.S. Environmental Protection Agency (EPA). Data were collected from four sites on nearby Tanners Creek in Indiana. The composite samples were collected from nine transects and processed using U.S. EPA's EMAP macroinvertebrate sampling and laboratory protocols. The single samples were collected one at each of three randomly selected transects, but the three samples were processed in the laboratory as separate samples (not composited). The biological data were analyzed using a Stream Benthos Interity Index (SBII), consisting of 10 metrics. The data indicated that similar results were obtained using either sampling method. The SBII scores for the sites were ranked in the same order using either method, and these rankings were according to expectations based on chemical and physical conditions. We conclude that collecting and processing three random single samples from each stream reach gave the same SBII score as collecting nine samples and compositing them. The three sample method allows a measure of repeatability which gave more confidence in the results of the sampling data. The collection effort was 1/3 that required for the composite method and in this study the sorting and identification effort was considerably reduced. We recommend that additional studies be conducted on other types of streams to determine if the three sample method might reduce effort and expense in EMAP studies elsewhere.
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| PRESENTATION |
Occurrence of Two Leech Species (Annelida: Hirudinea) on Fishes in the Kentucky River |
06/03/2001
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Flotemersch, J. E. AND D. J. Klemm. Occurrence of Two Leech Species (Annelida: Hirudinea) on Fishes in the Kentucky River. Presented at North American Benthological Society, La Crosse, WI, June 3-8, 2001.
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Little is known specifically on the feeding relationships between parasitic leeches and fish in North America. During an electrofishing survey conducted on the main stem of the Kentucky River in the summer of 2000, the presence of leeches was documented on six species of fish. The leech species observed were Piscicolaria reducta (Meyer, 1940) of the family Piscicolidae and Actinobdella pediculata (Hemingway, 1908) in the family Glossiphoniidae. Attachment locations for Piscicolaria reducta included various sites in the buccal cavity of green sunfish (Lepomis cyanellus), largemouth bass (Micropterus salmoides), and spotted bass (Micropterus punctulatus), on the caudal fin of logperch (Percina caprodes) and spotfin shiner (Notropis spilopterus), on the anal fin of spotfin shiner, and posterior to the eye of a largemouth bass. Attachment location observed for Actinobdella pediculata was on the inside of the operculum of a freshwater drum (Aplodinotus grunniens). This study established new host and attachment locations, the diverse presence of Piscicolaria reducta on various fish species, and substantiated the high degree of host specificity of Actinobdella pediculata for the freshwater drum.
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| PRESENTATION |
Evaluation of Biological Activity of Vitellogenin Expression in Different Aquatic Mesocosm Tropic Levels |
11/11/2001
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Gordon, D. A., D. L. Lattier, J. M. Lazorchak, T. V. Reddy, L. W. Chang, G. P. Toth, D. W. Graham, F. J. deNoyelles, S. E. Campbell, D. E. Williams, AND B. E. Wiechman. Evaluation of Biological Activity of Vitellogenin Expression in Different Aquatic Mesocosm Tropic Levels. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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Aquatic mesocosms were dosed with an environmentally relevant concentration of 17-a-ethinyl estradiol (EE2) to study the significance of trophic status (N, P levels) on the attenuation and bioavailability of synthetic estrogens in aquatic ecosystems. Estrogenic activity was assessed by the measurement of vitellogenin gene (Vg) expression in the liver of caged adult male fathead minnows (Pimephales promelas) using synthetic oligonucleotide primers which detect Vg messenger RNA in a quantitative reverse transcription-polymerase chain reaction. Caged male adult fathead minnows (Pimephales promelas) were maintained in outdoor mesocosms at the University of Kansas' Nelson Field Station and exposed to 0 or 20 ng/L EE2 at oligotrophic (total N and P, 0.77 and 0.015 mg/L), mesotrohpic (total N and P, 1.09 and 0.022 mg/L), or eutrophic (total N and P, 1.99 and 0.032 mg/L) nutrient levels. Randomly selected individuals were sacrificed at timepoints of 0, hr, 8 hr, 24 hr, 4 days, 7 days and 14 days post exosure and the livers were harvested for total RNA preparation. Vg expression was observed as early as 8 hr post exposure in all three trophic levels. Trend differences were observed among the three levels at the various timepoints. These results indicate that trophic level is a critical factor for assessing bioavailability of synthetic estrogens to aquatic species as part of a complete ecological risk assessment. These results will also provide data for the systhesis of environmental compartmental models for the fate and transport of model EDCs in aquatic ecosystems.
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| PRESENTATION |
Evaluation of Pilot Treatment Effluents from Summitville Mine, CO, Using Ceriodaphnia Dubia, Fathead Minnow (Pimephales Promelas), and Rainbow Trout (Oncorhynchus Mykiss) Toxicity Tests |
11/11/2001
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Lazorchak, J. M., M. E. Smith, E. R. Bates*, AND G. Miller. Evaluation of Pilot Treatment Effluents from Summitville Mine, CO, Using Ceriodaphnia Dubia, Fathead Minnow (Pimephales Promelas), and Rainbow Trout (Oncorhynchus Mykiss) Toxicity Tests. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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| Abstract:
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As part of a Superfund Innovative Technology Evaluation (SITE) Program, the U.S. Environmental Protection Agency evaluated a remediation technology at the Summitville Mine Superfund site in southern Colorado. The technology evaluated was a successive alkalinity producing system (SAPS) for removing high concentrations of metals (aluminum, copper, iron, manganese and zinc). Two treated and one untreated water samples were evaluated using a series of acute aquatic toxicity tests with the fathead minnow (Pimephales promelas) and the daphnid (Ceriodaphnia dubia), and a subchronic 7-day survival and growth toxicity test using rainbow trout (Oncorhynchus mykiss). All tests used moderately hard reconstituted water as the control and dilution water. The fathead minnows used in this study were three days old, the C. dubia were <24 hr old, and the rainbow trout used were 18 days old, 5 days post swimup. The trout tests were conducted at 15oC, the two other species were tested at 20oC. C. dubia were more sensitive than rainbow trout, which were more sensitive than the fathead minnow. Both treated samples reduced toxicity of the mine discharge by approximately 7-8 fold for C. dubia, 10 fold for rainbow trout, and about 5 fold for the fathead minnow. However, in order to remove all the acute toxicity from the mine discharge, a 1000 fold reduction in metals in both treatments would be needed for C. dubia survival, a 100 fold more reduction in the concentration of metals would be needed for rainbow trout survival, and a 50 fold reduction for fathead minnow survival.
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| PRESENTATION |
Gene Expression and Genetic Damage Indicators in Fish Exposed to Varying Stream Conditions in a Midwestern Watershed |
11/11/2001
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Chang, L. W., J. R. Meier, F. B. Daniel, J. M. Lazorchak, D. L. Lattier, AND G. P. Toth. Gene Expression and Genetic Damage Indicators in Fish Exposed to Varying Stream Conditions in a Midwestern Watershed. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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| Abstract:
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Newly developed molecular diagnostic exposure indicators were evaluated as part of a riparian zone assessment for environmental stressors. Water and fish samples collected from 12 headwater tributaries in the Little Miami River Basin were evaluated for the presence of estrogenic compounds and polycyclic aromatic hydrocarbons, measured by vitellogenin (Vg) and cytochrome P4501A1 (P450) gene expression, respectively; and genotoxicants, measured by single cell gel electrophoresis (SCG) and micronucleus (MN) assays. Larval fathead minnows (Pimephales promelas) were exposed to stream water and a laboratory control water for 24 hours. Total RNA was isolated and Vg and P450 gene expression were measured using designed synthetic oligonucleotide primers in quantitative RT-PCR. Fish blood samples obtained from bluegill sunfish (Lepomis macrochirus) and white suckers (Catostomus commersoni) were used for the SCG and MN analyses. For the SCG assay, the tail moment parameter was analyzed by computerized image analysis. Micronucleus frequencies were analyzed in polychromatic erythrocytes (PCE) and normochromatic erythrocytes (NCE), and the PCE:NCE ratio determined. Results indicated an increase in P450 gene expressio in fathead minnow larvae exposed to water samples from all 12 streams as compared to control laboratory water, the highest being observed in Turtle Creek. A marginal increase in Vg gene expression was observed only in three streams. Neither the SCG or MN parameters from fish blood cells showed evidence of significant exposure to genotoxic contaminants in any of the streams. Relational databases for a range of field-measured stream condition paramerters--land cover metrics, nutrient levels, and in-stream habitat measures--will be discussed.
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| PRESENTATION |
Ecotoxicogenomics: Exposure Indicators Using Ests and Subtractive Libraries for Multi-Life Stages of Pimephales |
11/11/2001
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Lattier, D. L., R. Flick, J. M. Lazorchak, G. P. Toth, M. E. Smith, D. E. Williams, AND B. E. Wiechman. Ecotoxicogenomics: Exposure Indicators Using Ests and Subtractive Libraries for Multi-Life Stages of Pimephales. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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| Abstract:
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Ecotoxicogenomics is research that identifies patterns of gene expression in wildlife and predicts effects of environmental stressors. We are developing a multiple stressor, multiple life stage exposure model using the fathead minnow (Pimephales promelas), initially studying four chemicals across three early life stages. We report studies of fathead minnows exposed to 17-a-ethinyl estradiol (0, 2, 5, 10 and 20 ng/L) for 24 h at the following life stages: 7 days old, 14 days and 60 days. These stages correspond to distinct developmental windows prior to notable reproductive organogenesis. Early development was targeted because of the genomic plasticity and the legions of transcriptional programs occurring during ontogeny. Following exposure, total RNA was isolated from organisms pooled by age and across doses. This RNA was used to construct forward and reverse cDNA subtraction libraries for each life stage, or to identify expressed sequence tags (ESTs) using differential display. Several differentially expressed products show identity with structurally characterized teleost sequences in GenBank. Subtractive cDNA clones will be used to construct an exposure-specific Pimephales microarray. The identical approach will be applied with a pesticide, common environmental metal, and a potent inducer of the P4501A1 gene. Following generation of these libraries, a multi-exposure microarray will be assembled. This will yield the foundation of expressed gene patterns that correlate with single or complex toxicant exposures, and the relative bioavailable concentrations of environmental stressors. This approach will also identify genes critical in early development, the disruption of which could influence reproductive outcomes, and detect differential expression patterns influenced by chronic chemical exposure, in comparison to acute onset of exposure.
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| PRESENTATION |
Evaluation of a Wastewater Discharge Using Vitellogenin Gene Expression and Plasma Protein Levels in Male Fathead Minnows |
11/11/2001
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Lazorchak, J. M., J. M. Hemming, J. Allen, D. B. Huggett, B. W. Brooks, D. L. Lattier, M. E. Smith, B. E. Wiechman, T. V. Reddy, AND D. A. Gordon. Evaluation of a Wastewater Discharge Using Vitellogenin Gene Expression and Plasma Protein Levels in Male Fathead Minnows. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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Liver vitellogenin gene expression and plasma vitellogenin protein presence, indicators of exposure of fish to estrogens, were measured in male fathead minnows (Pimephales promelas) caged at two locations in a constructed wetland below a sewage treatment plant effluent outfall in Pecan Creek, TX. Control fish were held in activated charcoal-dechlorinated tap water in the laboratory at similar densities. Adult fish from the USEPA, National Exposure Research Laboratory's Aquatic Research Facility were shipped to the University of North Texas and held for a 2-day acclimation period before deployment. Ten fish were collected at 0, 1, 2, 4, 7, 14 and 21 days. At these intervals male secondary sex characteristics were scored; hepatic and gonadal somatic indices (HSI, GSI) were calculated; livers analyzed for vitellogenin gene expression; blood analyzed for vitellogenin protein; and hematocrit and fish condition factor were determined. Equilenin, estradiol, estrone and ethynylestradiol were analyzed in water collected at the two exposure locations on days 1, 7 and 21. Plasma vitellogenin protein was detected in fish at site 1 within 2 days of exposure and peaked within 7 days. Liver vitellogenin gene expression followed a similar trend. HSI at site 1 was significantly elevated by the end of the exposure period, but GSI was not simultaneously decreased. Results indicate that liver vitellogenin gene expression and plasma protein were higher in male fish caged closest to the wastewater discharge than in laboratory controls. Additionally, at site 1, the secondary sex characteristics fatpad thickness and number of breeding tubercles decreased with exposure time and were significantly decreased toward the end of the exposure period.
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| PRESENTATION |
Development of a Stream Benthic Macroinvertebrate Integrity Index (Sbmii) for Wadeable Streams in the Mid-Atlantic Highlands Region |
11/11/2001
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Klemm, D. J., K. A. Blocksom, F. A. Fulk, A. T. Herlihy, P. R. Kaufmann, W. Davis, R. M. Hughes, D. V. Peck, J. L. Stoddard, W. T. Thoeny, AND S. M. Cormier. Development of a Stream Benthic Macroinvertebrate Integrity Index (Sbmii) for Wadeable Streams in the Mid-Atlantic Highlands Region. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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The Stream Benthic Macroinvertebrate Integrity Index (SBMII), a multimetric biotic index for assessing biological conditions of wadeable streams, was developed using seven macroinvertebrate metrics (Ephemeroptera richness, Plecoptera richness, Trichoptera richness, Collector-Filterer richness, Percent 5 Dominant taxa, Percent Non-Insect individuals, and Hilsenhoff Biotic Index). Benthic macroinvertebrate assemblage data were collected from 574 stream sites in the Mid-Atlantic Highlands Region (MAHR) of the U.S. during 1993-1995 as part of the USEPA's Environmental Monitoring and Assessment Program and the Mid-Atlantic Highlands Assessment. Macroinvertebrates were collected from 546 riffle/run habitats and 223 pool/glide habitats of first, second, and third order wadeable streams and identified to the lowest taxon possible in the laboratory. Water chemistry, Rapid Bioassessment Protocols habitat data, and minimum macroinvertebrate count criteria were used to identify reference and impaired sites. Over 100 candidate macroinvertebrate metrics, which included richness, composition, eveness, pollution tolerance, and trophic function measures, were evaluated statistically for (1) adequacy of range, (2) precision, (3) responsiveness, and (4) redundancy. Using statistical criteria, the relationships among macroinvertebrate metrics, habitat condition, anthropogenic disturbances, knowledge of reference and impaired sites based on chemical and physical habitat criteria, and best professional judgement were used to develop the SBMII for the assessment of stream condition in the MAHR. The scoring criteria for determining the biological condition (Good, Fair, Poor) were established using reference sites. Macroinvertebrate population and community structure data of riffle/run and pool/glide habitats were assessed for the stream site biological condition using the SBMII. Results indicate that the SBMII will help USEPA regions and states to determine the biological conditions or general health of freshwater wadeable streams which could lead to a better understanding of stream ecosystems for their protection, preservation, and restoration.
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| PRESENTATION |
Historical Monitoring of Biomarkers of Exposure of Brown Bullhead |
11/11/2001
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Lin, E. C., T. W. Neiheisel, J. E. Flotemersch, B. Subramanian, S. M. Cormier, D. E. Williams, M. E. Lowry, AND M. R. Millward. Historical Monitoring of Biomarkers of Exposure of Brown Bullhead. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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Biomarkers of exposure to chemical contamination, benzo(a)pyrene (BAP) and naphthalene (NAPH) type metabolites were measured in brown bullhead from a heavily polycyclic aromatic hydrocarbon (PAH) contaminated section of the Black River, Ohio during and immediately after remedial sediment dredging in 1990-1991, and in follow-up visits in 1993 and 1998. Biomarker levels in bullhead from the historically polluted Cuyahoga River and the protected Old Woman Creek National Estuarine Sanctuary in Ohio were also measured over the same time periods. PAH-bile metabolite concentrations of bullhead from the Black River were still elevated in the year following dredging, but were significantly lower in the later resampling years. Metabolite concentrations in Cuyahoga River bullhead decreased significantly between 1991 and 1993, possibly in response to the shutdown of coking operations on the river. Fish from the Old Woman Creek site showed some variation in metabolite levels among periods, but were consistently lower than the other two rivers. Measurement of bile metabolites proved an effective tool for estimating changes in exposure over time and among sampling sites. Trends in biomarkers indicated lowered exposures in the Black and Cuyahoga Rivers. These findings are likely a result of remediation activities in the Black River and source reduction and incidental sediment displacement in the Cuyahoga River.
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| PRESENTATION |
Ecoregional Influences on Watershed Land Cover, Water Quality, and in-Stream Biology |
11/11/2001
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Daniel, F. B., T. Flum, J. M. Lazorchak, AND F. H. McCormick. Ecoregional Influences on Watershed Land Cover, Water Quality, and in-Stream Biology. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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Omernik's ecoregions were developed to serve as a spatial framework for environmental monitoring and research. We examined the biology and chemistry in 35 headwater streams in the Little Miami River (LMR) of Ohio to determine whethEr there were real differences among three ecoregions. Land cover/land use features for the catchments and riparian corridors were evaluated along with variables related to geomorphology, hydrology, in-stream physical habitat, water chemistry, and fish, macroinvertebrate and periphyton assemblages. Although all of the watersheds in this study are dominated by row crop agriculture, differences in geomorphology, such as slope and soil types, lead to variations in land cover/land use such as relative differences in percent row crop or forest in both the catchments and the riparian corridors. Water quality variables, including nutrients (e.g., nutrients could be changed to total phosphorus, nitrate + nitrite nitrogen, ratio of dissolved organic to dissolved inorganic nitrogen, chloride, and sulfate) were significantly different among the ecoregions. In contrast, there were no significant differences among the ecoregions with respect to in-stream physical habitat measures. Likewise, we found no significant differences in biological indices (e.g., index of biotic integrity, and/or invertebrate community indices) or individual metrics for any taxonomic groups. Thus, the significant physical differences among ecoregions in the LMR did not necessarily translate into quantifiable in-stream biological differences. The absence of correlations between abiotic conditions and land cover/land use with biological assemblages among the ecoregions may be related to the historical degradation of in-stream physical habitat from human alterations.
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| PRESENTATION |
Exposure Method Considerations for Measuring Vitellogenin Expression in Larval and Male Fathead Minnows (Pimephales Promelas) |
11/11/2001
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Reddy, T. V., J. M. Lazorchak, D. E. Williams, B. E. Wiechman, D. L. Lattier, L. W. Chang, AND G. P. Toth. Exposure Method Considerations for Measuring Vitellogenin Expression in Larval and Male Fathead Minnows (Pimephales Promelas). Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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Our laboratory has developed methods for measuring the expression of the vitellogenin (Vg) gene in larval and adult male fathead minnows. During this development we found several conditions that affect background Vg levels and we observed preconditions for the expression of this gene. The first finding was that there was some basal level of Vg expression in early life stages of larval fathead minnows (4-24 h old). We hypothesize that this was due to maternal transfer. The second finding was that the males showed some level of Vg expression when housed together with females or separated from females for some period of time. We hypothesize that this was a population control mechanism due to male-female feedback interactions. To evaluate maternal transfer of Vg message in larval fathead minnows we measured Vg expression at 4, 24, 48 and 72 h post hatch. To evaluate male-female association effects we measured Vg expression in males mixed with females for up to 6 months, then separated from females for up to 4 weeks. Results of the larval tests indicated that there was detectable Vg expression at 4 and 24 h, but not in larvae that were older than 24 h post hatch. In addition, when larvae that were <24 h old and 24-48 h old were exposed to ethynylestradiol, greater Vg expression was found in the <24 hr old exposed larvae compared to 24-48 h old larvae.
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| PRESENTATION |
Assessing the Impacts of Anthropogenic Stressors on Macroinvertebrate Indicators in Ohio |
11/11/2001
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Majumder, S., F. A. Fulk, AND S. M. Cormier. Assessing the Impacts of Anthropogenic Stressors on Macroinvertebrate Indicators in Ohio. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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In the past few years, there has been increasing interest in using biological community data to provide information about specific anthropogenic factors impacting streams. Previous studies have used statistical approaches that are variants of classical and modern multiple regression with subsets of data on environmental and anthropogenic influence. This study attempts to gather data to answer questions about specific levels of stressors in different areas that can cause significant impairment. A series of generalized linear models have been developed to predict and classify macroinvertebrate indicator scores across the various ecoregions in Ohio. This differs from other regression techniques in that it predicts the probability of a location having a specific score, rather than levels of decreasing macroinvertebrate indicator scores with increasing stream impairment. Initial models confirm the existence of a few major stressors within each ecoregion that predict a decline in macroinvertebrate scores. Urbanization and levels of Total Kjeldahl Nitrogen were found to be the strongest predictors of decline in macroinvertebrate scores. The model fits are good in the Western Allegheny Plains ecoregion and less so in the Huron/Erie Lake Plains ecoregion. Further work is planned to incorporate environmental factors such as stream order, slopes and soil types to improve the fit of the models and to use them in developing threshold levels for stressors. Such models can then be used to identify locations for protection and where maximum benefits can be obtained from resources.
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| PRESENTATION |
A Survey of Fish Contamination in Small Wadeable Streams in the Mid-Atlantic Region |
11/11/2001
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Autrey, B. C., K. A. Blocksom, F. A. Fulk, AND S. M. Cormier. A Survey of Fish Contamination in Small Wadeable Streams in the Mid-Atlantic Region. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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Fish tissue samples were collected from wadeable streams in the Mid-Atlantic region of the United States (1993-1994). Whole fish tissue samples were prepared from prioritized lists of small and large target species. The two types of samples were analyzed for 56 contaminants, including metals and pesticides, of which 22 had median values that were above the detection limits for at least one category of fish. Data analyses were conducted in order to determine the exposure to contaminants, magnitude of exposure, and locations of sites which exceeded toxicological benchmark values. All sites from which samples were taken showed exposure to at least one contaminant. In order to determine the magnitude of this exposure, no observed adverse effects level (NOAEL) benchmark values for 16 of the analytes were used. The NOAEL benchmark values were compared to the concentration of contaminants found in small target species tissue sampled at each site. Maps were generated which showed the locations of the sites that exceeded the NOAEL benchmark values. Seventy sites (100%) exceeded at least one NOAEL benchmark value and 22 sites (31.43%) exceeded four or more NOAEL values. The number of sites exceeding multiple NOAEL benchmark values suggests a comprehensive study of fish tissue contaminants is warranted for the region.
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| PRESENTATION |
Hyperspectral Channel Selection for Water Quality Monitoring on the Great Miami River, Ohio |
11/11/2001
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Shafique, N. A., B. C. Autrey, F. A. Fulk, AND S. M. Cormier. Hyperspectral Channel Selection for Water Quality Monitoring on the Great Miami River, Ohio. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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During the summer of 1999, spectral data were collected with a hand-held spectroradiometer, a laboratory spectrometer and airborne hyperspectral sensors from the Great Miami River (GMR), Ohio. Approximately 80 km of the GMR were imaged during a flyover with a Compact Airborne Spectrographic Imager sensor. Approximately 10 km were imaged during a second flyover to repeat coverage of the urban influences around the city of Dayton, Ohio. Instream measurements of water quality data such as chlorophyll a concentrations, turbidity levels and Secchi disk depth were acquired on the same days as the flyovers. Relationships between optical water quality parameters and one or two broad wavebands were determined. Generally, atmospheric characters had negligible effects on the wavebands used or could be considered as spectrally additive constants in all wavebands. Because this assumption was not met for turbidity, the alternative and theoretically more robust derivative of reflectance was used. A high correlation was observed between these narrow wavebands (spectral channels) and water quality parameters. Based on this correlation, semi-quantitative models were developed to produce maps of the relative distributions of chlorophyll a and turbidity from the hyperspectral images of the river.
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| PRESENTATION |
Development of Epic Genetic Markers and the Utility of a Multi-Locus, Multi-Taxa Phylogeographical Approach to Examining Patterns of Genetic Diversity |
11/11/2001
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Sloss, B. L. AND M. J. Bagley. Development of Epic Genetic Markers and the Utility of a Multi-Locus, Multi-Taxa Phylogeographical Approach to Examining Patterns of Genetic Diversity. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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Use of population genetic measures for assessing the structure of natural populations and the condition of biological resources has increased steadily since the 1970's. Traditionally, genetic diversity within and among geographic areas is assessed based on a one-time sampling of select sites and measures of allelic frequencies. In addition to measuring spatial patterns of genetic diversity, population genetic measures of biological resources should include temporal data which indicate whether the observed patterns are the result of historical or contemporary processes. Allele frequency data from one-time sampling of populations are poor indicators of temporal processes. The use of individual gene genealogies combined with allele frequency data permit the inference of temporal processes from one-time samples of spatial patterns. The value of this phylogeographic approach has been clearly demonstrated with mitochondrial DNA data; however, reliance on a single locus for any genetic study is error-prone. We are developing 12-16 EPIC (Exon-Primed, Intron-Crossing) primers designed to amplify homologous intron regions within teleost genomes. This development will aid in fish population analyses, including stock identification, estimates of gene flow, effective population size, and effects of environmental change. In addition, multi-species assessment of homologous markers permits a more accurate assessment of patterns of biodiversity and the condition of biological resources across a wide geographical area. Intron regions from eight nuclear genes (c-myc proto-oncogene, K-ras, Pax transcription factor, 40S ribosomal protein 24, GTPase, ependymin, and alpha crystallin) have been amplified and cloned for creek chub (Semotilus atromaculatus), central stoneroller (Campostoma anomalum), white sucker (Catostomus commersoni), brown bullhead (Ameiurus nebulosus) and/or green sunfish (Lepomis cyanellus). These loci will be combined with mtDNA data to analyze the distribution of genetic diversity of creek chub, central stoneroller and white sucker within USEPA's Mid-Atlantic Integrated Assessment (MAIA) study area.
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| PRESENTATION |
Genetic Variation for Copper Resistance in Fathead Minnow Toxicity Tests |
11/11/2001
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BrownAugustine, M. C., M. J. Bagley, J. M. Lazorchak, M. E. Smith, AND S. I. Guttman. Genetic Variation for Copper Resistance in Fathead Minnow Toxicity Tests. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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Unexplained variation in the results of aquatic organism toxicity tests is a consistently observed and troubling phenomenon. Possible sources of variation include differences in condition or nutritional status of the population prior to the test, as well as age, density and handling of organisms during the test. One source of variation in test outcomes that is often overlooked is genetic variability within and among stocks of test organisms. The goal of the current study is to assess the relative magnitude of among-stock and within-stock genetic variation for resistance to copper in fathead minnows. Three commercial stocks and one USEPA in-house stock of fathead minnows were reared at the National Exposure Research Laboratory in Cincinnati. Within each stock, mature fish have been paired in spawning chambers with the aim of producing up to 40 full-sib families, divided into approximately 20 paternal half-sib and 20 maternal half-sib progeny groups. Larval fish were exposed to copper at 14-days post hatch, and monitored for mortality in a series of 48-hour time-to-death tests. Preliminary results, which presently have only considered covariances between a subset of the full-sib families, suggest that genetic variation for copper susceptibility within stocks is greater than variation among stocks. As data on half-sib covariances becomes available, we will more thoroughly examine the contributions of additive genetic, nonadditive genetic, and maternal effects to variance in fathead minnow toxicity.
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| PRESENTATION |
A Multi-Locus, Multi-Taxa Phylogeographical Analysis of Genetic Diversity |
10/13/2001
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Sloss, B. L. AND M. J. Bagley. A Multi-Locus, Multi-Taxa Phylogeographical Analysis of Genetic Diversity. Presented at Southeastern Association of Fish and Wildlife Agencies, Louisville, KY, October 13-17, 2001.
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| Abstract:
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In addition to measuring spatial patterns of genetic diversity, population genetic measures of biological resources should include temporal data that indicate whether the observed patterns are the result of historical or contemporary processes. In general, genetic measures focused solely on allele frequencies are poor indicators of temporal processes. The use of allele genealogies and allele frequency data permit the inference of temporal processes from one-time samples of spatial patterns. The value of this phylogeographic approach has been clearly demonstrated with mitochondrial DNA data. However, reliance on a single locus for any genetic study is error prone. We are developing 12-16 EPIC (Exon-Primed, Intron-Crossing) primers designed to amplify homologous intron regions within teleost genomes. These loci will aid in population analyses, including stock identification, estimates of gene flow, effective population size, and effects of environmental change. In addition, multi-species assessment of homologous markers permits a more accurate assessment of patterns of biodiversity and the condition of biological resources across a wide geographical area. Intron regions from eight nuclear genes (c-myc proto-oncogene, K-ras, Pax transcription factor, 40S ribosomal protein 24, GTPase, ependymin, and alpha crystallin) have been amplified and cloned for Semotilus atromaculatus (creek chub), Campostoma anomalllum (central stoneroller), Catostomus commersoni (white sucker), Ameiurus nebulosus (brown bullhead) and/or Lepomis cyanellus (green sunfish). These loci will be combined with mtDNA data to analyze the distribution of genetic diversity in creek chub, central stoneroller, and white sucker within USEPA's Mid-Atlantic Integrated Assessment (MAIA) study area.
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| PRESENTATION |
Transcriptional Signatures as a Measure of Environmental Stress |
11/11/2001
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Lewis, S., S. J. Keller, D. L. Lattier, J. M. Lazorchak, AND M. E. Smith. Transcriptional Signatures as a Measure of Environmental Stress. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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One day old larvae of p. promelas were treated with copper sulfate at dosages from 6.25 to 100 ug/ml. After 48 hours, the survivors were collected and RNA was purified from the treated and unexposed controls. Recovered transcripts were analyzed by differential display using fluorescent anchored primers. A comparison of three independent experiments indicated that there is a reproducible transcriptional pattern between treated and control post-hatched larvae. To date, 591 cDNAs have been identified using 13 different anchored primer combinations. Thirty-three of the bands were considered to be anomalous since they did not show reproducibility within the triplicate. Five cDNA bands were significantly increased/decreased in their fluorescent intensities as a result of copper treatment. Two of the cDNA bands were increased whereas three cDNA bands were reduced. The 6% variability observed within the triplicate samples suggests the results are due to either genetic or environmental variations since larval survival under these conditions varied from 56% to 91%. Experiments are in progress to identify the copper stress genes and confirm their induction/repression.
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| PRESENTATION |
Empirical Risk Relationships Between Invertebrates, Habitat and Water Quality in Maia Data Sets |
11/11/2001
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Benjamin, R. B., F. A. Fulk, AND S. M. Cormier. Empirical Risk Relationships Between Invertebrates, Habitat and Water Quality in Maia Data Sets. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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A technique for developing a non-weighted risk index, originally developed for use with Ohio fish assemblage data, was applied to invertebrate, habitat and water quality data collected from Mid-Atlantic streams of the U.S. during 1997-98. Multiple habitat and water quality variables were treated as predictors of individual invertebrate assemblage variables. Conventional multivariate methods were poorly suited for analyzing the observed MAIA data distrubutions. Predictor and response variables were rank ordered and sorted into high, moderate or low categories. Most responses were significantly associated with six to nine predictors which were selected using a combination of discriminant analyses and Chi-Square tests. For each response variable, the Maximum Response Profile (MRP) was defined as the combination of significant predictor categories resulting in the greatest frequencies of high-response categories (one-on-one predictor and response comparisons). A Risk Index (RI) was computed for each response variable at each sampling location. Each RI was the total number of significant, categorized predictors at each time/location not falling into the MRP. Increased RIs were consistently associated with increased frequencies of low-response categories. Results were different between data collected from riffles or pools, and some response variables could not be satisfactorily explained using this approach. Successful application of this empirical technique to both fish and invertebrate assemblages suggests it has broad applicability.
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| PRESENTATION |
Simple Empirical Risk Relationships Between Fish Assemblages, Habitat and Water Quality in Ohio |
11/11/2001
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Benjamin, R. B., F. A. Fulk, AND S. M. Cormier. Simple Empirical Risk Relationships Between Fish Assemblages, Habitat and Water Quality in Ohio. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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To assess the condition of its streams, fish, habitat and water quality data were collected from 1980 to 1998 by the Ohio Environmental Protection Agency. These data were sorted into 190 time/locations by basin, river mile and year. Eighteen fish community variables and 24 habitat or water quality variables were represented in each time/location. Because sample sizes were not constant, the central tendencies for each time/location were described as means (fish and habitat) or as medians (water quality). Approximately one half of the central tendencis were bimodal or multimodal following Box-Cox transformations. Non-parametric analyses of untransformed data simplified data trend analysis and increased statistical robustness. Predictor and response central tendencies were rank ordered and sorted into high, moderate and low categories. Most responses were significantly associated with four to seven predictors as selected by discriminant analyses and confired with Chi-Square tests. For each response variable, one Maximum Response Profile (MRP) was defined as the combination of significant predictor variables resulting in the greatest frequencies of high category responses. A Risk Index (RI) was computed for each of the 18 fish variables at each sampling location. Each RI was the total number of significant, categorized predictors at each time/location not falling into the MRP. Increased RIs were consistently associated with increased frequencies of low-category responses. This is a promising empirical risk assessment tool for use when environmental data are collected from multiple sources.
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| PRESENTATION |
Differential Display Analyses of the Amphipod Hyalella Azteca Exposed to Ethynylestradiol at Three Different Trophic Levels |
11/11/2001
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Flick, R., D. L. Lattier, J. M. Lazorchak, M. E. Smith, D. E. Williams, S. E. Campbell, F. J. deNoyelles, T. V. Reddy, D. W. Graham, AND G. P. Toth. Differential Display Analyses of the Amphipod Hyalella Azteca Exposed to Ethynylestradiol at Three Different Trophic Levels. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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| Abstract:
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A study was conducted to determine if differential display could be used to detect differences in gene expression in the amphipod, Hyalella azteca. In a study of synthetic estrogen attenuation in different aquatic media, amphipods were exposed to 20 ng/L 17 a-ethynylestradiol in mesocosms at low (total N and P, 0.77 and 0.015 mg/L, respectively), medium (total N and P, 1.09 and 0.022 mg/L), and high (total N and P, 1.99 and 0.32 mg/L) nutrient levels. Amphipods were deployed on the bottom and below the surface of mesocosms with and without 17 a-ethynylestradiol for 2 days. PVC couplers (4 x 6 cm) enclosed at each end with 250 micron (#60) Nitex mesh were used as exposure chambers. Amphipods were then recovered and stored in RNAlater (Ambion) until needed for RNA isolation. RNA samples were pooled across replicate nutrient levels into groups exposed at the top and bottoms of the mesocosms. Total RNA was isolated and reverse transcribed using an anchored oligo-dT primer. cDNAs were subsequently amplified in a PCR reaction using fluorescent TMR-labeled anchored oligo-dTprimers and one of several arbitrary decamers. The PCR products were separated on a polyacrylamide gel and visualized with a fluorescent scanner. Several bands were identified that exhibited differential expression between amphipods exposed to 17 a-ethynylestradiol and controls. These bands were excised from the gel, and the cDNAs were re-amplified and sequenced. We plan to verify differential expression through semi-quantitative PCR using primers generated from the cDNA sequences. These techniques promise to expand the use of amphipods as biomonitors of contaminants in sediments and water.
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| PRESENTATION |
Biliary PAH Metabolites as a Biological Indicator of Fish Exposure in Tributaries of Lake Erie |
11/11/2001
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Yang, X., D. S. Peterson, P. C. Baumann, AND E. C. Lin. Biliary PAH Metabolites as a Biological Indicator of Fish Exposure in Tributaries of Lake Erie. Presented at Society of Environmental Toxicology and Chemistry, Baltimore, MD, November 11-15, 2001.
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| Abstract:
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Biliary polynuclear aromatic hydrocarbons (PAH) metabolites have been studied as a biological indicator of fish exposure to PAHs since the mid 1980's. Brown bullheads were collected from the following Lake Erie tributaries: Buffalo River (BUF), Niagara River at Love Canal (NIA), Old Woman Creek (OWC), Ottawa River (OTT), Cuyahoga River-harbor (CRH), Cuyahoga River-upstream (CRUP), Ashtabula River (ASH) and Detroit River (DET). Bile was taken for analysis and fish were examined for external pathology. The concentrations of benzo(a)pyrene type and Naphthalene type PAH metabolites in the bile of fish were estimated using Fixed-wavelength fluorescence (FF). External pathology of fish included counts of raised lesions and counts of abnormalities on each barbel, such as shortening and knobs of scar tissue. Fish from the reference site OWC and the extensively remediated Niagara River at Love Canal contained the lowest levels of biliary PAH metabolites. In fish from BUF, CRH and CRUP, which are industrially polluted, PAH metabolites were about an order of magnitude higher. The same trend was found in the external abnormalities, with fish from CRH and CRUP having seven to sixteen times the barbel deformities and four to six times the raised lesions as fish from OWC. A good correlation was obtained between the biliary PAH concentrations and the prevalence of external abnormalities in the fish from all of the Lake Erie tributaries. Our study provides added evidence that fish biliary PAH metabolites can be used as a biological indicator of fish exposure and effects.
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| PRESENTATION |
Assessment of Large River Macroinvertebrate Assemblages: How Far Is Enough? |
10/30/2001
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Flotemersch, J. E., J. J. Hutchens, K. A. Blocksom, D. J. Klemm, AND B. C. Autrey. Assessment of Large River Macroinvertebrate Assemblages: How Far Is Enough? Presented at Southeastern Water Pollution Biologists Association, Bowling Green, KY, October 30-November 1, 2001.
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During the summer of 2001, twelve sites were sampled for macroinvertebrates, six each on the Great Miami and Kentucky Rivers. Sites were chosen in each river from those sampled in the 1999 methods comparison study to reflect a disturbance gradient. At each site, a total distance equal to 40 times the mean wetted width was sampled at specific intervals. Timed kick net and dip/pick samples were combined into a single sample for each transect and bank. The relationship of distance sampled with metrics and species composition, as well as variability among transects and between banks, will be analyzed to determine the most efficient sampling design for these rivers.
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| PRESENTATION |
The Effect of Varying Electrofishing Design on Bioassessment Results of Four Large Rivers in the Ohio River Basin |
10/30/2001
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Flotemersch, J. E. AND K. A. Blocksom. The Effect of Varying Electrofishing Design on Bioassessment Results of Four Large Rivers in the Ohio River Basin. Presented at Southeastern Water Pollution Biologists Association, Bowling Green, KY, October 30-November 1, 2001.
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In 1999, the effect of electrofishing design (single bank or paired banks) and sampling distance on bioassessment results was studied in four boatable rivers in the Ohio River basin. The relationship between the number of species collected and the total distance electrofished was similar across all four rivers. In addition, the pattern was similar whether a single bank or paired banks design was used, with 75-80% of taxa collected within the first 1000 m of a 2000 m total sampling distance. However, in the Great Miami River, sampling along a single bank collected a slightly higher percentage in the first 1000 m than sampling along both banks. Only one of the rivers showed a bias toward more species collected with a single bank design, but the overall similarity of fish species between the single and paired banks designs was quite high. The similarity of new species collected in non-overlapping sections of the two designs decreased with increasing depth. These results indicate that identifying the appropriate electrofishing design may depend on physical characteristics of a given reach.
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| PRESENTATION |
Large River Assessment Methods for Benthic Macroinvertebrates and Fish |
10/30/2001
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Flotemersch, J. E. AND K. A. Blocksom. Large River Assessment Methods for Benthic Macroinvertebrates and Fish. Presented at Southeastern Water Pollution Biologists Association, Bowling Green, KY, October 30-November 1, 2001.
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Multiple projects are currently underway to increase our understanding of the varying results of different sampling methods and designs used for the biological assessment and monitoring of large (boatable) rivers. Studies include methods used to assess fish, benthic macroinvertebrates, algae and physical habitat. a brief overview of the early results for sampling fish and benthic macroinvertebrates will be presented in more detail during the poster session. Other ongoing large river research being conducted will also be discussed.
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| PUBLISHED REPORT |
Comparisons of Boating and Wading Methods Used to Assess the Status of Flowing Waters |
04/01/2001
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Flotemersch, J. E., B. C. Autrey, AND S. M. Cormier. Comparisons of Boating and Wading Methods Used to Assess the Status of Flowing Waters. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-00/108 (NTIS PB2001-102899), 2001.
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This document has been designed to provide an overview of the biological, physical and chemical methods of selected stream biomonitoring and assessment programs. It was written to satisfy the need to identifiy current methods that exist for sampling large rivers. The primary focus of this document is the boating methods used to assess flowing waters, but both boat-based and wading methods are included. The target audiences are individuals tasked: 1) to work with data generated from one or more of these programs; 2) to design or improve a bioassessment and monitoring program; 3) to conduct field work using methods (or based on methods) reviewed in this text; 4) to conduct field comparisons among these methods to determine the extent of their comparability and when each method is best employed.
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| PUBLISHED REPORT |
Logistics of Ecological Sampling on Large Rivers |
04/01/2001
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Flotemersch, J. E., B. C. Autrey, AND S. M. Cormier. Logistics of Ecological Sampling on Large Rivers. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-00/109 (NTIS PB2001-102900), 2001.
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The objectives of this document are to provide an overview of the logistical problems associated with the ecological sampling of boatable rivers and to suggest solutions to those problems. It is intended to be used as a resource for individuals preparing to collect biological data from large rivers. Its greatest benefit to project planners will be the knowledge and awareness necessary to provide a greater level of safety to the crew members who will be collecting ecological data on large rivers. A large river can be a hazardous work environment, but can be made relatively safe with adequate training and preparation. In addition to the safety benefit, this document will provide the means needed to ensure the accurate and complete collection of data. The execution of preparatory steps outlined in this document will minimize the collection of inaccurate or incomplete data, thereby decreasing wasted time and money. A third benefit that can be derived from this document is the more efficient collection of data in the field. There are many aspects of conducting ecological research on large rivers which can cause delayed or inefficient data collection. A well-designed study with adequate preparation, including thorough training of field crews, will minimize problems and maximize efficiency, which will increase the likelihood of successful field endeavors.
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| PUBLISHED REPORT |
A Survey of Fish Contamination in Small Wadeable Streams in the Mid-Atlantic Region |
02/01/2001
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Fulk, F. A. AND S. M. Cormier. A Survey of Fish Contamination in Small Wadeable Streams in the Mid-Atlantic Region. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-00/107 (NTIS PB2001-101937), 2001.
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In 1993 and 1994, fish tissue samples were collected from first, second and third order streams in the Mid-Atlantic Region of the United States.The tissue samples were prepared from whole fish from prioritized lists of Small Target Species and Large Target Species. The two types of samples were analyzed for 56 contaminants, of which 22 had median values that were above the detection limits for at least one category of fish. For this report, the data analyses were conducted in order to determine 1) exposure to contaminants, 2) the magnitude of exposure, and 3) the location of the sites which exceeded toxicological benchmark values. All sites from which samples were taken show exposure to at least one contaminant. In order to determine the magnitude of this exposure, No Observed Adverse Effects Level (NOAEL) benchmark values for 16 of the analytes were used. These NOAEL benchmark values are estimates of the greatest concentration of contaminants at which it is unlikely that the belted kingfisher (Megaceryle alcyon) would suffer adverse effects from consumption. These NOAEL benchmark values were then compared to the concentration of contaminants found in Small Target Species tissue sampled at each site. Maps were generated which showed the locations of the sites that exceeded at least one NOAEL benchmark value and twenty two sites (10.53%) exceeded four or more NOAEL benchmark values. The number of sites exceeding multiple NOAEL benchmark values suggests a comprehensive study of fish tissue contaminants is warranted for the region.
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| PUBLISHED REPORT |
Stressor Identification: Technical Guidance Document |
03/01/2001
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Cormier, S. M., S. B. Norton, G. Suter, AND D. ReedJudkins. Stressor Identification: Technical Guidance Document. U.S. Environmental Protection Agency, Washington, DC, EPA/822/B-00/025 (NTIS PB2001-104770), 2001.
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| Abstract:
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Since the inception of the Clean Water Act (CWA) in 1972, the rivers, lakes, estuaries, and wetlands of the United States have indeed become cleaner. The standard for meassuring these improvements are both chemical and biological. Yet, we know that many waterbodies still fail to meet the goal of the Clean Water Act--to maintain the chemical, physical and biological integrity of the nation's waters. Biological assessments have become increasingly important tools for managing water quality to meet the goals of the CWA. These methods, which use measurements of aquatic biological communities, are particularly important for evaluating the impact of chemicals for which there are no water quality standards, and for non-chemical stressors such as flow alteration, siltation and invasive species. However, although biological assessments are critical tools for detecting impairment, they do not identify the cause or causes of the impairment. The Office of Water and Office of Research and Development have developed a process for identifying any type of stressor or combination of stressors that cause biological impairment. The Stressor Identification (SI) Guidance is intended to lead water resource managers through a formal and rigorous process that identifies stressors causing biological impairment in aquatic ecosystems, and provides a structure for organizing the scientific evidence supporting the conclusions. The ability to accurately identify stressors and defend the evidence supporting those findings is a critical step in developing strategies that will improve the quality of aquatic resources. The Stressor Identification process is prompted by biological assessment data indicating that a biological impairment has occurred. The general SI process entails critically reviewing available information, forming possible stressor scenarios that might explain the impairment, analyzing those scenarios, and producing conclusions about which stressor or stressors are causing the impairment. The SI process is iterative, usually beginning with a retrospective analysis of available data. The accuracy of the identification depends on the quality of data and other information used in the SI process. In some cases, additional data collection may be necessary to accurately identify the stressor(s). The conclusions can be translated into management actions and the effectiveness of those management actions can be monitored.
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