bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application ofCeriodaphnia dubiafor whole effluent toxicity tests in the hawkesbury–nepean watershed, New South Wales, Australia: Method development and validation
Authors: Bailey Howard C , Krassoi Rick , Elphick James R , Mulhall Ann-Maree , Hunt Peta , Tedmanson Louise , Lovell Adam 
Published: March 2010

AbstractUse of Ceriodaphnia dubia for whole effluent toxicity testing programs is widespread in North America. However, the methods used for this species in the United States and Canada have not been validated in Australia for use in local waters with the local variant of the species. Consequently, we compared the effects of container size and volume, diet, and dilution water on the survival and reproduction of the local variant of C. dubia (the Sydney clone). We also evaluated the results of control performance and reference toxicant tests with potassium chloride and diazinon obtained over the course of a whole effluent toxicity testing program conducted on effluents discharged from sewage treatment plants into the Hawkesbury–Nepean drainage basin. Our data indicate that the general guidelines published by the U.S. Environmental Protection Agency for conducting acute and chronic toxicity tests with C. dubia can be successfully applied to the Sydney clone with minor modifications and that both acute and chronic tests can be conducted with a high degree of success, provided that appropriate procedures are followed. Moreover, tests with a variety of chemicals indicated that the Sydney clone responded comparably to its North American counterparts, suggesting that existing databases for C. dubia can be applied to the Sydney clone. In addition, the use of test volumes between 20 and 200 ml did not affect the acute toxicity of the organophosphorous pesticide diazinon to this strain.
Metabolic responses to subacute toxicity of trace metals in a marine microalga (Thalassiosira weissflogii) measured by calorespirometry
Authors: Reinfelder John R , Jablonka Rachel E , Cheney Marcos 
Published: March 2010

Abstract
Metabolic responses to the subacute toxicities(non-growth-rate inhib iting)ofCd, Cu, and Znweremeasured in the coastal marine diatom Thalassiosira weissflogii using calorespirometry. Respiratory heat production and oxygen consumption rates were measured in diatom cells grown with concentrations of Cd2+ (10−12 to 10−8 M), Cu2+ (10−138 to 10−98 M), and Zn2+ (10−109 to 10−6.9 M) that are typical of urban and suburban coastal waters. These trace metals did not significantly inhibit diatom growth rates in high-nutrient, high-light laboratory cultures except for the highest concentrations of Cd (Cd2+ = 10−8 M) and Zn (Zn2+ = 10−6.9 M). Respiratory heat rates in cells grown with elevated, but non-growth-rate-inhibiting free Cu2+ ion concentrations (10−11.8 to 10−9.8 M) were up to 40% higher and oxygen consumption rates were 50 to 75% lower than control ([Cu2+] = 10−13.8 M) cells indicating a subacute depression of respiratory efficiency in Cu-exposed cells. Exposure to elevated free Cd2+ concentrations (10−10 to 10−8 M) caused dramatic short-term (hours) increases (five- to eight-fold) in respiratory oxygen consumption rates, which returned to normal in acclimated cells, suggesting a transient disruption of metabolism upon Cd exposure. Zinc did not significantly affect either respiratory parameter up to a free Zn concentration of 10−7.9 M, above which diatom growth rate was significantly reduced. The subacute toxic effects of Cd and Cu were more pronounced in low Mn than in Mn-replete cells, consistent with proposed Mn-Cd, -Cu antagonisms in marine phytoplankton. The range of free Cu2+ ion concentrations in coastal waters is similar to that found to cause a decrease in respiratory efficiency in T. weissflogii, thus coastal marine diatoms may be subject to the subacute metabolic toxicity of Cu. Free Cd2+ concentrations in coastal waters are below those found to cause transient subacute stress in T. weissflogii. Calorespirometry proved to be a sensitive tool for the assessment of the subacute toxicity of contaminant trace metals.
Hazard assessment of temephos applied to a southwest Florida, USA, salt marsh community
Authors: Pierce Richard H , Henry Michael S , Kelly Dan , Kozlowski Wendy 
Published: March 2010

Abstract
This investigation was undertaken to determine whether the mosquito larvicide temephos (applied as Abate 4-E ®) created an environmental hazard for nontarget organisms in a southwest Florida salt marsh community. Field toxicity tests were performed during routine larvicide applications using larvae of salt marsh crabs (Aratus pesonii and Uca rapax) and adult Mysidopsis bahia. Laboratory toxicity tests were performed using survival through 48 and 96 h and through first molt as toxicity endpoints. Larvae of both species exhibited 96 h lowest observable effects concentration (LOEC) in the range of 15 to 20 μg/L temephos. First-molt LOEC ranged from 7 to 12 μg/L. No effect on M. bahia survival, growth, or fecundity was observed up to 40 μg/L temephos. Field studies of routine temephos application rates produced an expected environmental concentration (EEC) of 12 ± 10 μg/L in marsh water, causing an environmental hazard to crab larvae. Reduction of the application rate effectively reduced the EEC to 4 ± 3 μg/L, indicating no hazard for 48 and 96 h toxicity; however, a hazard was observed for survival through the first molt. This information was used to modify larviciding applications to effect a reduction of the environmental hazard to nontarget organisms in the salt marsh.
What level of effect is a no observed effect?
Authors: Crane Mark , Newman Michael C 
Published: March 2010

Abstract
The no observed effect concentration (NOEC) is currently a major summary statistic in ecotoxicity testing. Its use is heavily criticized, partly because it is a poor estimator of “safe” chemical concentrations. In this short communication, we review the limited information available on the percentage effect that corresponds with the NOEC, a value designated the ECNOEC, and calculate ECNOEC values for fish growth data. The average ECNOEC for different test protocols was found to vary widely, with values for chronic studies ranging from 10 to 34%. Individual results varied even more widely. This analysis suggests that the NOEC is neither a consistent summary statistic nor an indicator of safe concentrations of toxic chemicals.
Cytotoxicity of settling particulate matter and sediments of the Neckar River (Germany) during a winter flood
Authors: Hollert Henner , Dürr Matthias , Erdinger Lothar , Braunbeck Thomas 
Published: March 2010

Abstract
To investigate the cytotoxic and genotoxic potentials of settling particulate matter (SPM) carried by the Neckar River, a well-studied model for a lock-regulated river in central Europe, during a flood, acute cytotoxicity was investigated using the fibroblast-like fish cell line RTG-2 with the neutral red retention, the succinic acid dehydrogenase (MTT), and the lactatedehydro-genase (LDH) release assays as well as microscopic inspection as endpoints. Genotoxicity of water, pore water, sediments, and SPM were assessed using the Ames test. Different extraction methods (Soxhlet extraction with solvents of variable polarity as well as a fluid/fluid extraction according to pH) in addition to a supplementation of biotests with S9 fractions from the liver of β-naphthoflavone/phenobarbital-induced rats allowed a further characterization of the biological damage. Both sediments and SPM extracts caused cytotoxic effects in RTG-2 cells. Cytotoxicity was found to increase significantly with polarity of extracting solvents (NR50 = effective concentration for 50% cell death in the neutral red test: 80 [65], 100 [70], 180 [220], and 225 [270] mg/ml for ethanol, acetone, dichloromethane, and n-hexane extracts, respectively, if measured with [without] S9 supplementation). Following extraction according to pH, cytotoxicity could be attributed mainly to neutral substances (NR50: 80 and 218 mg dry SPM/ml test medium for the neutral and the acid fractions, respectively), whereas the slightly acid and basic fractions already showed little or no cytotoxicity. Samples taken during the period of flood rise showed the highest cytotoxic activities. Cytotoxicity was significantly enhanced by the addition of S9 preparations. In contrast, no genotoxic activity was found in native surface waters, pore waters, and SPM.
Aerobic biodegradation of monobranched aliphatic alcohol polyethoxylates
Authors: Marcomini Antonio , Pojana Giulio , Carrer Claudio , Cavalli Luciano , Cassani Giorgio , Lazzarin Mario 
Published: March 2010

Abstract
Aerobic biodegradation of the 2-butyl-octyl alcohol polyethoxylate (2Bu-C8AE) was investigated under laboratory standardized conditions (Organization for Economic Cooperation and Development 301E and 310B screening test protocols) to study the effect of the 2-alkyl chain length on the biodegradation mechanism of monobranched alcohol polyethoxylates (AEs). The 2Bu-C8AE was compared with linear and monobranched AEs with short 2-alkyl chains, which were simultaneously tested under the same inoculum conditions. The metabolites identified and the primary biodegradation rate constants obtained indicate that the alkyl chain length of the 2-alkyl substituent is the factor governing the biodegradation pathway of monobranched AEs. Short 2-alkyl substituents (i.e., methyl and ethyl groups) allow the central cleavage mechanism to occur, which leads to the formation of polyethylene glycols, whereas AEs with longer alkyl substituents, such as the 2Bu-C8AE, biodegrade through hydrolytic oxidation of the alkyl and polyethoxylic chains, which leads to formation of AE metabolites with carboxylic groups on both the hydrophobic and hydrophilic moieties.
Accumulation of heavy metals by vegetables grown in mine wastes
Authors: Cobb George P , Sands Kristin , Waters Melissa , Wixson Bobby G , Dorward-King Elaine 
Published: March 2010

Abstract
Lead, cadmium, arsenic, and zinc were quantified in mine wastes and in soils mixed with mine wastes. Metal concentrations were found to be heterogeneous in the wastes. Iceberg lettuce, Cherry Belle radishes, Roma bush beans, and Better Boy tomatoes were cultivated in mine wastes and in waste-amended soils. Lettuce and radishes had 100% survival in the 100% mine waste treatments compared to 0% and 25% survival for tomatoes and beans, respectively. Metal concentrations were determined in plant tissues to determine uptake and distribution of metals in the edible plant parts. Individual soil samples were collected beneath each plant to assess metal content in the immediate plant environment. This analysis verified heterogeneous metal content of the mine wastes. The four plant species effectively accumulated and translocated lead, cadmium, arsenic, and zinc. Tomato and bean plants contained the four metals mainly in the roots, and little was translocated to the fruits. Radish roots accumulated less metals compared to the leaves, whereas lettuce roots and leaves accumulated similar concentrations of the four metals. Lettuce leaves and radish roots accumulated significantly more metals than bean and tomato fruits. This accumulation pattern suggests that consumption of lettuce leaves or radish roots from plants grown in mine wastes would pose greater risks to humans and wildlife than would consumption of beans or tomatoes grown in the same area. The potential risk may be mitigated somewhat in humans, as vegetables grown in mine wastes exhibited stunted growth and chlorosis.
Characterizing aquatic ecological risks from pesticides using a diquat dibromide case study. II. Approaches using quotients and distributions
Authors: Campbell Kym Rouse , Bartell Steven M , Shaw Jennifer L 
Published: March 2010

Abstract
Realistic and reliable methods are needed for the accurate characterization of the potential ecological risks posed by pesticides. This study presents a sequence of risk assessment methods that are based on the comparison of exposure concentrations to laboratory-derived toxicity data for representative species of aquatic organisms exposed to pesticides. The sequence of methods progresses from single-value quotient calculations to comparison of cumulative distributions of exposure and toxicity data and culminates with the use of Monte Carlo methods to estimate distributions of quotients. To illustrate the sequence of increasingly quantitative methods, we used a case study of the ecological risks posed by diquat dibromide in U.S. regional lakes and farm ponds. Diquat dibromide is a well-studied aquatic herbicide and is one of only a few pesticides registered for direct use in aquatic systems. The exposure concentration for the farm pond scenario used in the U.S. Environmental Protection Agency reregistration eligibility decision for diquat dibromide was used. In addition, exposure concentrations were developed for several regional lake and farm pond scenarios using the Exposure Analysis Modeling System (EXAMSII) methodology with separate, region-specific parameter values and simulated diquat dibromide application rates. Except for the results obtained in the conservative quotient method, the calculations for diquat dibromide were consistent with its demonstrated high safety. This suggests that a minimal ecological impact to benthic invertebrates and fish exists. Aquatic plants in the vicinity of application to surface waters appear to be at risk, and this is expected, as diquat dibromide kills aquatic plants. Comparisons of cumulative distributions of exposure and toxicity data provided the most quantitative approach to characterizing risks. The probabilistic quotient approach does not specifically estimate ecological risk. However, the implicit correlation between increasing values of quotients and increased potential risk does suggest the utility of these methods for identifying pesticides as acceptable for registration and use (i.e., minimal risk compared to benefits) or unacceptable.
Metal toxicity inferred from algal population density, heterotrophic substrate use, and fatty acid profile in a small stream
Authors: Genter Robert B , Lehman R Michael 
Published: March 2010

AbstractThe purpose of this study was to examine relations between metal concentrations in periphyton and the abundance of algal species, heterotrophic use of 95 carbon sources, and phospholipid fatty acids (PLFA) of the periphyton in a small stream spanning a mine in Lemhi County, Idaho, USA. Two upstream, two mine, and two downstream sites were examined. Elevated concentrations of As and Cu at the mine sites were associated with communities that were depleted of diatoms and filamentous blue-green algae and characterized by a low-diversity community dominated by a single blue-green alga and patchy populations of the diatom Achnanthidium minutissimum and a filamentous green alga. Carbon source use and PLFA profiles provided a rapid assessment of stream conditions that were consistent with algal taxonomy and with our hypotheses constructed from previous reports on periphyton responses to metal stress.
Laboratory to field validation in an integrative assessment of an acid mine drainage–impacted watershed
Authors: Soucek David J , Cherry Donald S , Currie Rebecca J , Latimer Henry A , Trent G Claire 
Published: March 2010

AbstractAn integrative assessment was conducted in the Puckett's Creek watershed of southwestern Virginia, USA, to investigate the environmental impacts of acid mine drainage (AMD) inputs. Twenty-one sampling stations were categorized into groups based on five degrees of AMD input: (1) none, (2) intermittent acidic/circum-neutral AMD, (3) continuous acidic AMD, (4) continuous circum-neutral AMD, and (5) receiving system stations with at least two levels of dilution. Bioassessment techniques included water/sediment chemistry, benthic macroinvertebrate sampling, laboratory acute water column toxicity testing, laboratory chronic sediment toxicity testing, and in situ toxicity testing with Asian clams (Corbicula fluminea [Müller]). Group 3 stations had significantly altered water chemistry (low pH, high conductivity, and high water column metals) relative to the other groups and significantly higher sediment iron concentrations. Both group 3 and group 4 stations had significantly decreased ephemeroptera-plecoptera-trichoptera richness and percent ephemeroptera abundance relative to unimpacted stations. Group 3 stations also had decreased total taxon richness. Water column toxicity testing was sensitive to AMD impacts, with samples from group 3 stations being significantly more toxic than those from groups 2 and 4, which in turn were more toxic than those from groups 1 and 5. Similar results were observed for in situ toxicity testing. No differences in sediment toxicity test survival and impairment results were observed among the station groups. Stepwise multiple linear regression and simple bivariate correlation analyses were used to select parameters for use in an ecotoxicologic rating system, which was successful in differentiating between two levels of environmental impact relative to stations receiving no AMD input.
Bottom-up and top-down approaches to assess multiple stressors over large geographic areas
Authors: Dyer Scott D , White-Hull Charlotte , Carr Gregory J , Smith Eric P , Wang Xinhao 
Published: March 2010

Abstract
The relationship of multiple factors, such as instream habitat, drainage area, gradient, cumulative effluent, conventional pollutants, and chemical mixtures, to fish communities was explored at the subbasin, basin, and state level within the state of Ohio, USA. Two approaches were used: bottom-up, which focused on subbasin- and basin-level relationships within the Great Miami River, Ohio, and top-down, focusing on relationships across the entire state. Data were provided by the Ohio Environmental Protection Agency and the U.S. Environmental Protection Agency. These data were integrated via a geographical information system. Multiple linear regression was used to determine the strength of stressor–response relationships. The greatest amount of variation of the index of biotic integrity (IBI) and selected metrics was addressed at the subbasin level, followed by the basin and state level, respectively. Overall, habitat factors were the best predictors and positively related to the IBI and number of fish species. Chemical factors, such as cumulative effluent, metals, ammonia, and biochemical oxygen demand, were consistently observed as negative, moderating factors for IBI and fish taxa richness and were the best predictors of the percent of fish observed with deformities, fin erosions, lesions, and tumors.
Estrogen receptor- and aryl hydrocarbon receptor-mediated activities of a coal-tar creosote
Authors: Fielden Mark R , Wu Zhi-Fen , Sinal Christopher J , Jury Heather Hodgert , Bend John R , Hammond Geoffrey L , Zacharewski Tim R. 
Published: March 2010

AbstractA coal-tar creosote was examined for estrogen receptor (ER)–and aryl hydrocarbon receptor (AhR)–mediated activity using a battery of mechanistically based assays. In vitro, creosote was found to bind to the mouse ER, bind to the human sex hormone–binding globulin, and elicit partial agonist activity in reporter gene assays in transiently transfected MCF-7 cells. Based on competitive binding to the mouse ER, creosote contains approximately 165 mg/L of estradiol-equivalents. Creosote effectively transformed the AhR in vitro and induced a Cyp1a1-regulated luciferase reporter gene in transiently transfected Hepa 1c1c7 cells. Based on dose–response curves, creosote contains approximately 730 mg/L of dioxin-equivalents. Creosote did not exhibit any AhR-mediated antiestrogenic activity in vitro. In vivo, creosote significantly induced liver pentoxyresorufin O-depentylation and ethoxyresorufin-O-deethylation (EROD) in a dose-dependent manner in ovariectomized (OVX) ICR mice, but did not increase uterine weight wet or vaginal cornification, due possibly to AhR-mediated antiestrogenic activity. In OVX DBA/2 mice, a strain less responsive to AhR ligands, creosote induced liver EROD to a lesser extent, but still did not show an increase in uterine wet weight or vaginal cornification. These results demonstrate that coal-tar creosote exhibits AhR- and ER-mediated activity in vitro, but its dioxinlike activity may suppress estrogenic responses in vivo.
Effects of 4-nonylphenol on fecundity and biomarkers of estrogenicity in fathead minnows (Pimephales promelas)
Authors: Giesy John P. , Pierens Susan L , Snyder Erin M , Miles-Richardson Stephanie , Kramer Vincent J , Snyder Shane A , Nichols Krista M , Villeneuve Daniel A 
Published: March 2010

Abstract
Aultfathead minnows (Pimophales promelas) were exposed to waterborne concentrations of 4-nonylphenol (NP) ranging from 0.05 to 3.4 μg NP/L for 42 d. Results were similar, but slightly different, for two experiments conducted during July and August, near the beginning of the breeding season, and a second experiment conducted during September and October, at the end of the breeding season, during which the adults were maintained continuously in breeding condition. Inverted U–type dose-response relationships were observed for egg production and for concentrations of vitellogenin (Vtg) and 17β-estradiol (E2) in blood plasma. Concentrations of plasma Vtg were significantly different between males and females, with plasma concentrations in females ranging from 20 to 110 μg Vtg/ml. Both experiments had no statistically significant, dose-dependent effect of NP on plasma Vtg in males but significant effects of NP on Vtg concentrations in females. In the first experiment, Vtg concentration generally increased with NP concentration, whereas the second experiment showed a negative correlation. Plasma E2 concentrations in both males and females were significantly affected by NP. The concentration of total estrogen equivalents in the plasma increased 900% because of exposure to NP. Most of this increase resulted from increased plasma E2 concentrations, with only a 4% increase resulting from the estrogen agonist activity of NP. The effects of NP on adult fathead minnows seem not to result from a direct-acting estrogen agonist mechanism but rather from changes in the endogenous concentrations of E2 through an indirect activation mechanism of action.
Some bioaccumulation factors and biota-sediment accumulation factors for polycyclic aromatic hydrocarbons in lake trout
Authors: Burkhard Lawrence P , Lukasewycz Marta T 
Published: March 2010

Abstract
Bioaccumulation factors (BAFs) and biota-sediment accumulation factors (BSAFs) for phenanthrene, fluoranthene, pyrene, benz[a]anthracene, and chrysene/triphenylene were calculated using the tissue data of Zabik et al. for Salvelinus namaycush siscowet with a 20.5% lipid content, the water data of Baker and Eisenreich, and the sediment data of Baker and Eisenreich for the Lake Superior ecosystem. Log BAFs, both lipid normalized and based on the freely dissolved concentration of the chemical in the water, of 1.95, 3.22, 4.72, 4.73, and 3.61 were calculated for phenanthrene, fluoranthene, pyrene, benz[a]anthracene, and chrysene/triphenylene, respectively. The BSAFs for phenanthrene, fluoranthene, pyrene, benz[a]anthracene, and chrysene/triphen-ylene were 0.00011, 0.00016, 0.0071, 0.0054, and 0.00033, respectively.