bluuebunny/crossref_metadata_2025_split huggingface dataset:
A new fathead minnow (Pimephales promelas) subchronic toxicity test
Authors: Norberg Teresa J. , Mount Donald I. 
Published: March 2010

Abstract
The most commonly used test for evaluating the toxicity of effluents to fish and invertebrates has been the acute lethality test. However, effluents frequently are not acutely toxic, and so assessing the sublethal effects on fish and invertebrates is important. Described herein is a rapid method to estimate the chronic toxicity of effluents to the fathead minnow (Pimephales promelas). Tests are initiated using newly hatched minnow larvae and are run for 7 d under static-renewal conditions. It is a cost-effective, simple, short-term toxicity test, and survival and growth are the measures of effects. Approximately 70 tests using this technique have been run with various types of effluents. Included in this article are results from representative effluent tests and also from tests conducted using Dursban, zinc and copper. The results indicate that this subchronic toxicity test gives a good estimate of chronic toxicity.
Biotransformation of chlorinated organic solvents in static microcosms
Authors: Parsons Frances , Lage Gladys Barrio , Rice Ramona 
Published: March 2010

Abstract
The presence of trichloromethane and volatile chlorinated ethene compounds in local groundwater, where no use of these compounds could be determined, prompted a search for their source using models of the aquifer in the laboratory. Preliminary work indicated that chloroethene and cis- and trans-1,2-dichloroethene resulted from subsurface transformation of spilled tetra- and trichloroethene, which are commonly used as industrial degreasers. This study was undertaken to determine the interactions and subsurface factors, including the microbiota and commonly used chlorinated organic solvents, which brought about these transformations.
Static microcosms containing groundwater and sediments were spiked with four organic solvents (tetrachloroethene, trichloroethene, 1,1,1-trichloroethane, and tetrachloromethane) and analyzed by GC at intervals during a 16-week incubation period. Eh and pH were determined concurrently.
The environmental conditions within the microcosms, i.e., neutral to acid pH and reductive potential, indicated that reductive dehalogenation was the pathway by which the observed products were formed. An aqueous milieu and the presence of electron donors and microbial mediators are believed to be influential factors. Evidently, one carbon-halogen bond in each of the solvents was ruptured to yield a compound with one fewer chlorine than its precursor. The products of transformations in microcosms were exotic compounds also found in the groundwater. They were formed only in microcosms from which living microorganisms were cultured.
Bioconcentration kinetics of 2,3,7,8-tetrachlorodibenzo-p-dioxin in rainbow trout
Authors: Branson Dean R. , Takahashi Irene T. , Parker William M. , Blau Gary E. 
Published: March 2010

Abstract
The uptake and depuration rate constants for [14C]2,3,7,8-tetrachlorodibenzo-p-dioxin (14C-TCDD) in growing rainbow trout were obtained in a laboratory experiment involving a 6-h static water uptake exposure at 107 ng/L (ppt) followed by a 139-d flow-through depuration period. Improved mathematics were developed for estimating uptake and depuration rate constants and an equilibrium bioconcentration constant that accounts for growth dilution of the total chemical body burden. The uptake and depuration rate constants (k1' and k2) for 14C-TCDD in rainbow trout (whole fish) were determined to be 108 ± 3 ml water/g whole fish/d and 0.012 ± 0.001 d−1, respectively. Based on these data, the equilibrium bioconcentration constant for TCDD, defined as the ratio of uptake to depuration rate constants, was 9,270 ± 1,050, and the elimination half-life, t1/2, of the total body burden was 58 ± 5 d. Clinical observations of the fish concurred with those previously reported by other researchers.
Plasma leucine aminonaphthylamidase as an indicator of acute sublethal toxicant stress in rainbow trout
Authors: Dixon D. G. , Hill C. E. A. , Kempe E. J. , Hodson P. V. , Kaiser K. L. E. 
Published: March 2010

Abstract
Leucine aminonaphthylamidase (LAN) is a lysosomal enzyme that appears in blood plasma after cell death. Levels of plasma LAN (PLAN) were assayed to quantify toxicant stress in rainbow trout in a series of experiments. Blood samples were taken from groups of fish weighing 80 to 100 g following intraperitoneal (i.p.) and/or waterborne exposure to p-methylphenol (PMP) or carbon tetrachloride (CCl4).
The duration of postinjection holding significantly affected PLAN activity in control and PMP-dosed rainbow trout; the largest increases occurred after 96 h. There were significant correlations between dose and PLAN activity after both PMP and CCl4 injection. PLAN levels of fish injected with PMP at doses of 0.075 to 0.75 of the 96-h i.p. LD50 were elevated by 27 to 63% relative to controls 96 h after injection. PLAN levels of fish injected with CCl4 at doses of 0.18 to 0.79 of the i.p. LD50 were elevated by 38 to 135% relative to controls 48 h after injection. Exposure of fish to a waterborne concentration of 0.028 mM PMP (0.41 96-h LC50) significantly increased PLAN activity after 48, 96 and 192 h; activities increased by 38 to 87% relative to controls. Elevated PLAN activity was strongly correlated with decreased plasma protein levels. The temperature and duration of plasma storage affected the measured PLAN activity of control and PMP-dosed rainbow trout. While diet modified PLAN activity, the gender of immature fish had no effect.
Hepatic lesions visible by light microscope were observed with waterborne PMP exposure; parenchymatous edema was closely associated with increased liver somatic index. There were, however, no visible lesions or changes in the index associated with the pulse i.p. doses of PMP and CCl4. In these cases, biochemical lesions preceded any evidence of histopathology.
Static acute toxicity of dibromonitrilopropionamide and selected degradation products to the fathead minnow (Pimephales Promelas rafinesque)
Authors: Mayes Monte A. , Blanchard Fred A. , Hopkins Daniel L. , Takahashi Irene T. 
Published: March 2010

Abstract
Dibromonitrilopropionamide (DBNPA) is the active ingredient in Dow Antimicrobials 7287® and 8536®. An important environmental feature of DBNPA is that it degrades very rapidly in water to a series of compounds including monobromonitrilopropionamide (MBNPA) and dibromoacetonitrile (DBAN). The objective of this study was to determine the toxicity of DBNPA, including the separate influences of the compound itself and of its degradation products, to the fathead minnow Pimephales promelas Rafinesque. The lability of DBNPA and the degradation products confounded the interpretation of the results. To aid in explaining the observed toxicity data, a model was used that treated DBNPA and its degradation products as a complex mixture, with the components having an assumed additive effect on the test species. Only DBNPA, MBNPA and DBAN were included in the evaluations because they were the primary components contributing to the toxicity of DBNPA, with 96-h LC50 values of 1.8, 3.4 and 0.55 mg/L, respectively. Analyses of the degradation and toxicity data confirmed the major role played by DBAN in the toxicity of initially applied DBNPA. They also suggested that in systems with nucleophilic activity, such as found in natural waters, there is a tendency to form more of the mono- and debrominated degradation products and fewer of the dibrominated degradation products, thus reducing the toxicity of initially introduced DBNPA.
Decomposition by planktonic and attached microorganisms improves chemical fate models
Authors: Lassiter R. R. , Burns L. A. , Parrish R. S. 
Published: March 2010

Abstract
Terms for decomposition by both suspended and attached microorganisms were included in a model to calculate the fate of chemicals in aquatic systems. This model differs from previous models primarily by the inclusion of a term for decomposition by aufwuchs in addition to a term for decomposition by planktonic microorganisms. Decomposition by aufwuchs is represented as occurring at a rate limited by the serial processes of transport to a planar surface and decomposition at the surface. Two sets of experiments were conducted using replicate laboratory microcosms, each maintained with six different environments. The predictive capability was good, as indicated by the absence of statistically detectable differences between predictions and laboratory measurements. In making the predictions, a set of parameters describing the characteristics of the chemical was required. Included in these parameters were the rate coefficients for the two microbial decomposition terms. With both microbial decomposition terms included, the fate model accounted satisfactorily for observed methyl parathion concentrations using only a single, environment-independent rate coefficient for each term.
Dynamics of organochlorine compounds in herring gulls (Larus argentatus): I. distribution and clearance of [14C]DDE in free-living herring gulls (Larus argentatus)
Authors: Norstrom Ross J. , Clark Thomas P. , Jeffrey Deborah A. , Won Henry T. , Gilman Andrew P. 
Published: March 2010

AbstractRadiolabelled [14C]DDE was used as a model compound to determine important factors in the clearance of persistent lipophilic compounds in free-living herring gulls (Larus argentatus). Adult, breeding male and female gulls were dosed orally during incubation and then captured one week and one year later. After one week, [14C]DDE had equilibrated with native DDE in all tissues. The ratios of DDE levels on a lipid weight basis relative to whole body were as follows: muscle, 0.8 to 0.9; liver, 0.5 to 0.7; egg, 0.4; and brain, 0.1. The plasma/whole body lipid partition coefficient was 0.0041 ± 0.0014. The whole body annual average clearance rate was 0.95 ± 0.51 year−1 (half-life = 264 d). Native DDE levels in males were twice those in females, but no differences were found for [14C)DDE after one year. The lower levels in females do not appear to be related to excretion of DDE in eggs or higher monooxygenase activity, but they may be related to differences in feeding ecology. Additional physiological and ecological factors must therefore be included in a proposed two-compartment (plasma/whole body lipid) model of residue levels in eggs based on experimental data from caged gulls.
Growth inhibition and morphological effects of several chemicals in Arabidopsis thaliana (L.) HEYNH
Authors: Ratsch H. C. , Johndro D. J. , McFarlane J. C. 
Published: March 2010

Abstract
A plant life-cycle bioassay using Arabidopsis thaliana (L.) Heynh. was used to evaluate effects of several toxic chemicals. Plants were grown in vermiculite in a hydroponic system, with test chemicals added to the nutrient solution reservoir. Reduction in total biomass followed different patterns with the chemicals tested, and sensitivity increased in the order: fly ash &gt; 2-(2-ethoxyethoxy)ethanol (DGME) &gt; dalapon &gt; trichloroacetic acid (TCA) &gt; copper sulfate &gt; bromacil &gt; metribuzin. DGME, TCA and dalapon induced unusual morphological effects in which flower development was altered and pollination prevented. Reduced biomass, altered distribution of plant dry weight among vegetative, reproductive and mature seed, and morphological effects indicate that a plant life-cycle test is a valuable screening test.
Effect of simulated acid rain on growth and yield of Valencia orange, floradade tomato and slash pine in Florida
Authors: Hart Robin , Biggs R. H. , Webb P. G. 
Published: March 2010

Abstract
Direct effects of simulated acidic deposition on vegetation were studied in the laboratory under controlled conditions for three commercially important resources: slash pine, Floradade tomato and Valencia orange. Treatment was similar to convective rain in Florida in ion composition, total volume, frequency and rate of application, intensity and sulfate/nitrate ratio. The surface of the growth medium was covered with plastic during application of the solution. Water and nutrients optimum for growth were provided directly to the growth medium. No visible injury resulted from application of the simulated rain. No effects of pH treatments on vegetative growth of slash pine, orange or tomato were observed. However, fruit yield of tomato and orange differed significantly between plants subjected to different pH treatments. The yield of tomato was lower and that of orange was higher at the lower pH treatments. Calcium and magnesium levels were highest in the foliage of tomato plants receiving the pH 5.5 treatment. No differences in element levels of orange foliage were observed.
Toxicity of fluridone to aquatic invertebrates and fish
Authors: Hamelink Jerry L. , Buckler Denny R. , Mayer Foster L. , Palawski Donald U. , Sanders Herman O. 
Published: March 2010

Abstract
The acute and chronic toxicities of the herbicide fluridone to aquatic invertebrates and fish were evaluated. The acute median lethal concentrations (LC50s) of fluridone were 4.3 ± 3.7 mg/L (x̄±SD) for invertebrates (n = 15) and 10.4±3.9 mg/L for fish (n = 28). In chronic studies, no effects were detected when daphnids (Daphnia magna) were continuously exposed to fluridone concentrations of 0.2 mg/L or less for 32 d, amphipods (Gammarus pseudolimnaeus) to 0.6 mg/L or less for 60 d or midge larvae (Chironomus plumosus) to 0.6 mg/L or less for 30 d. Fathead minnows (Pimephales promelas) were not affected by continuous exposure to fluridone concentrations of 0.48 mg/L or less over their life cycle. The growth and survival of channel catfish (Ictalurus punctatus) were not adversely affected by continuous exposure to fluridone concentrations of 0.5 mg/L or less for 60 d after hatching. The channel catfish accumulated fluridone concentrations two to nine times greater than that in the water. The recommended application rate of 1 lb/acre of fluridone to a pond with an average depth of 3 ft provides a theoretical concentration of 0.1 mg/L. Thus, an initial fluridone concentration of 0.1 mg/L or less is recommended to control weeds in ponds. Consequently, fluridone is not expected to have adverse effects on the species tested or on similar nontarget aquatic organisms.
Acute toxicity of cadmium, copper, mercury and zinc to Tropocyclops prasinus mexicanus (Cyclopoida, copepoda) from three quebec lakes
Authors: Lalande Marc , Pinel-Alloul B. 
Published: March 2010

Abstract
This study deals with cultures of Tropocyclops prasinus mexicanus, a Cyclopoid copepod from three Quebec lakes (one polluted and two unpolluted), in a comparative toxicity test involving four heavy metals. Experiments were performed according to a static toxicity protocol. The 48-h EC50 of each individual metal and of the combination of metals were determined for each culture. The overall toxicity trend is mixture &gt; Hg &gt; Cu ≥ Cd ≥ Zn. Cultures from unpolluted and low-hardness lakes showed lower EC50 mean values than did the strain originating from the polluted lake with high water hardness.
Trace metals in mussels transplanted to San Francisco Bay
Authors: Smith D. R. , Stephenson M. D. , Flegal A. R. 
Published: March 2010

Abstract
Mussels (Mytilus californianus) transplanted to San Francisco Bay exhibited elevated trace metal concentrations compared with those in other mussel watch studies on the west coast of the United States. The highest concentrations of Ag, Cu, Hg, Mn, Pb and Zn were at the South Bay stations, and often in the Redwood Creek area. Ag and Hg concentrations were linearly correlated with station distance from the North Bay (San Pablo Bay), indicating that the South Bay is a major reservoir of these pollutants within San Francisco Bay.
Toxicity of sodium monofluoroacetate (Compound 1080) to mink and European ferrets
Authors: Hornshaw T.C. , Ringer R.K. , Aulerich R.J. , Casper H.H. 
Published: March 2010

Abstract
The toxicity of sodium monofluoroacetate (Compound 1080) to mink (Mustela vison) and European ferrets (Mustela putorius furo) was evaluated through LC50 and reproduction tests. Subacute dietary exposure to Compound 1080 resulted in dose-dependent decreases in body weights and feed consumption in both species. The mink were more sensitive to Compound 1080 than were the ferrets. The 28-d dietary LC50 for mink and for ferrets was calculated to be 3.2 and 9.4 ppm, respectively. Dietary exposure to 0.80 ppm Compound 1080 for 2 months prior to breeding severely impaired reproduction in the mink, which was presumed to be due to oligo- or aspermia. In young, rapidly growing ferrets, red and white blood cell counts were adversely affected by dietary concentrations of Compound 1080 as low as 1.08 ppm. The 28-d LC50 test, however, revealed that young, rapidly growing animals may be unsuitable for tests of this duration unless precautions are taken to assure that they do not “outgrow” potentially lethal concentrations of the test chemical.
A method for measuring the biodegradation of organic chemicals
Authors: Boatman Rodney J. , Cunningham Suzanne L. , Ziegler Donald A. 
Published: March 2010

Abstract
An automated gas-chromatographic measurement of carbon dioxide is described and its application to a biodegradation screening test procedure is demonstrated. The biodegradation test system consists of 20-ml glass vials containing aqueous solutions of a test chemical and an acclimated microbial inoculum. The vials and their contents are sealed with rubber septa. At specified time intervals, the contents of selected vials are acidified. Subsequent automated headspace determination of carbon dioxide provides a measure of cumulative biological degradation. To demonstrate the validity of the overall test procedure, the biodegradabilities of eight organic compounds were measured: aniline, benzaldehyde, ethylenediaminetetraacetic acid, ethylene glycol, linear alkylbenzene sulfonate, nitrilotriacetic acid, p-nitrophenol and N-methylaniline. Biological degradation was also monitored by measuring residual test chemical concentrations. There was excellent internal consistency of results by comparison of carbon dioxide evolution values with specific chemical analyses. Both the results of carbon dioxide measurements and specific chemical analyses are discussed in relation to literature values derived from similar screening test procedures. It is concluded from this study that automated headspace determination of carbon dioxide has several advantages over existing test methods. It is further concluded that application of this headspace procedure in the screening test described provides an accurate, albeit conservative, estimate of biodegradability, with positive results indicating a low potential for environmental persistence.
Diatoms in daphnid culture and bioassay
Authors: Keating Kathleen Irwin , Dagbusan Brenda Caballero 
Published: March 2010

Abstract
For daphnids, the diatom Nitzschia frustulum is both a nutritionally desirable food and a source of essential organics not adequately provided by several green algae commonly fed daphnids in bioassays. Although a diet based on only one alga, Chlamydomonas reinhardti, generated more progeny per individual Daphnia pulex, progeny from broodmates fed diets differing only in that they also included diatoms were consistently more tolerant in acute toxicity bioassays. Feeding studies and bioassays were done in wholly defined inorganic media (MS system) that had contributed all essential inorganic nutrients for more than 100 consecutive generations of test daphnids. This limited the possibility of misinterpretation due either to deficiencies resulting from the absence of essential inorganics or to variations in media. Algae were grown in wholly defined inorganic media, versions of A-MS (algal version) that were similar to animal media excepting that additional N, P and Si, and the three vitamins (B12, thiamine, biotin) known to be needed by many algae were included.
Chloroform sorption to New Jersey coastal plain ground water aquifer solids
Authors: Uchrin Christopher G. , Mangels Gary 
Published: March 2010

Abstract
Studies examining the adsorption/desorption characteristics of chloroform to New Jersey coastal plain aquifer solids were performed. Adsorption to the Cohansey aquifer solids, a coarse-to-fine-grade sand with a 4.4% organic matter content (2.6% organic carbon content), and to the Potomac-Raritan-Magothy aquifer solids, a sandy loam with a 2.2% organic matter content (1.3% organic carbon content), was found to be dependent on adsorber mass. Equilibrium adsorption could be characterized by either linear or Freundlich isotherms. Greater adsorption was achieved to the Cohansey material, which was attributed to its greater organic matter (carbon) content. Calculated normalized organic carbon partition coefficients were compared with values obtained from literature correlations. Consecutive desorption experiments displayed an apparent hysteresis.
Relative sensitivity of three daphnid species to selected organic and inorganic chemicals
Authors: Elnabarawy Mohamed T. , Welter Alphonse N. , Robideau Rochelle R. 
Published: March 2010

Abstract
Static acute and renewal chronic tests were conducted with Daphnia magna, Daphnia pulex and Ceriodaphnia reticulata to determine their relative sensitivities to selected organic and inorganic chemicals: 2-chloroethanol, 2,4-pentanedione, pentachlorophenol, hexachloroethane, 2,2,2-trichloroethanol, 2-methyl-1-propanol, 2-methyl-2,4-pentadiol, Endrin®, silver, lead, chromium, cadmium, copper, arsenic and mercury. The three species tested yielded comparable acute EC50 values for most chemicals tested. The acute EC50 values for D. magna, D. pulex and C. reticulata varied twofold for hexachloroethane, Endrin, cadmium, arsenic and mercury. Chronic EC50 values for the three species were within one order of magnitude for 2-chloroethanol, 2,4-pentanedione, cadmium, chromium and silver. Differences in the sensitivities of these three popular cladoceran test species were within one order of magnitude. Reproductive impairment in all three test species appeared to be a more sensitive indicator of chronic toxicity than survival. This study suggests that the 7-d Ceriodaphnia chronic test may be used as an alternative short-term method for the screening of chemical toxicities.
Water quality-based criteria for toxics: Scientific, regulatory, and political considerations: Site-specific water quality criteria from in-stream monitoring data
Authors: Van Hassel John H. , Gaulke Alan E. 
Published: March 2010

AbstractThe determination of site-specific water quality criteria generally involves the recalculation of national criteria using laboratory-derived toxicity data or the conducting of bioassays using site water. Because of uncertainty of predictions of in-stream biological responses to contamination, an alternative procedure using stream benthic surveys and water quality data was applied at the Appalachian Power Company Clinch River Plant on the Clinch River in southwestern Virginia. Benthic surveys of riffle transects at four stations located upstream and downstream of the plant showed no significant differences among sites, except just below the effluent discharge site. During low-flow periods there were significant decreases at this site in the percentage of mayflies in the organisms collected.Effluent and ambient chemical data were examined statistically with respect to the biological data. Increased copper concentrations were significantly associated with decreases, from reference levels, in percent mayflies at the impacted area. A linear equation was derived relating decreased percent mayflies to increased copper concentrations. A no effect level based on the least detectable difference in percent mayflies produced a total recoverable copper criterion of 34.2 μg/L. Criteria or impact estimates derived from in-stream data possess many advantages; they are a valuable tool for reducing uncertainty through integrated field-laboratory assessments.