bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preliminary study to compare body residues and sublethal energetic responses in benthic invertebrates exposed to sediment-bound 2,4,5-trichlorophenol
Authors: Penttinen Olli-Pekka , Kukkonen Jussi , Pellinen Jukka 
Published: March 2010

Abstract
Relationships between concentration of 2,4,5-trichlorophenol (TCP) in sediment, body residues of the chemical, and sublethal biological effects in three benthic invertebrates were studied. Uncontaminated lake sediment was spiked with four concentrations (23–85 μg/g dry sediment) of TCP. Chironomid larvae (Chironomus riparius), oligochaete worms (Lumbriculus variegatus), and sphaeriid bivalves (Sphaerium corneum) were exposed to the sediment. The effect of chlorophenol on the rate of heat dissipation of animals was monitored by direct microcalorimetry. It appeared that both the behavior of the animals and their body residues explained the energetic response. Valve closure behavior of S. corneum reduced the accumulation of toxicant (&lt;0.3 μmol/g) but was observed as a complex energetic response. Heat dissipation of L. variegatus was at the same level in control animals and those with high body residues of TCP (&gt;1.5 μmol/g). Regardless of the amount of TCP accumulated to C. riparius (0.1–0.6 μmol/g), the rate of heat dissipation was almost two times higher than that of the control animals, probably reflecting uncoupling of oxidative phosphorylation, which is the primary mode of toxic action of chlorophenols. However, when a threshold concentration was exceeded there was no concentration-response dependence until acute toxicity appears.
Inhibition of testicular growth in rainbow trout (Oncorhynchus mykiss) exposed to estrogenic alkylphenolic chemicals
Authors: Jobling Susan , Sumpter John P. , Sheahan David , Osborne Julia A. , Matthiessen Peter 
Published: March 2010

Abstract
It is becoming evident that an increasing number of widely used industrial and agricultural chemicals are estrogenic. The biodegradation products of a major group of nonionic surfactants, the alkylphenol polyethoxylates, are one such group. Some of these chemicals are widespread aquatic pollutants, and bioconcentrate in aquatic biota. Exposure of male rainbow trout (Oncorhynchus mykiss) to four different alkylphenolic chemicals caused synthesis of vitellogenin, a process normally dependent on endogenous estrogens, and a concomitant inhibition of testicular growth. The magnitude of these estrogenic effects was dependent on the estrogenic potency of the chemical, the stage of reproductive development of the fish, and the concentration of the chemical in the water. These results support the contention that exposure of wildlife to environmentally persistent estrogenic chemicals can result in deleterious reproductive consequences.
Toxic potencies of lipophilic extracts from sediments and settling particulate matter (SPM) collected in a PCB-contaminated river system
Authors: Engwall Magnus , Broman Dag , Brunström Björn , Ishaq Rasha , Näf Carina , Zebühr Yngve 
Published: March 2010

Abstract
Sediments and settling particulate matter (SPM) were sampled in a polychlorinated biphenyl (PCB)-contaminated lake, Lake Järnsjön, and in lakes located up-/and downstream from Lake Järnsjön. The 7-ethoxyresorufin O-deethylase (EROD)-inducing potencies of lipophilic extracts from sediment and SPM were investigated in organ cultures of chicken embryo livers (denoted in vitro chicken embryo liver bioassay). The extract from sediments collected in Lake Järnsjön had the greatest EROD-inducing potency of the extracts studied, and it also contained the highest concentrations of PCBs, polycyclic aromatic hydrocarbons (PAHs), and polychlorinated dibenzodioxins/furans (PCDDs/Fs). The non-ortho-chlorinated PCBs in the extracts were probably major contributors to the EROD induction noted. The EROD-inducing potency of sediment extract from the lake downstream Lake Järnsjön was higher than that of extract from the upstream lake. This indicates that EROD-inducing substances were transported from Lake Järnsjön sediment to the lake downstream. The extracts from Lake Järnsjön sediment and SPM were separated into three fractions containing aliphatic/monoaromatic, diaromatic, and polyaromatic compounds, respectively, which were tested in the in vitro chicken embryo liver bioassay. In all extracts, the aliphatic/monoaromatic fractions were low in EROD-inducing potency, while the polyaromatic fractions from SPM were more potent than their corresponding diaromatic fractions, indicating that they contained high concentrations of aromatic hydrocarbon (Ah) receptor ligands. Only a small part of the EROD induction caused by the polyaromatic fractions could be attributed to the 15 analyzed PAHs in the samples. The EROD-inducing potencies of the diaromatic fractions correlated quite well with their concentrations of PCDDs/Fs and PCBs. The in vitro chicken embryo liver bioassay detected low concentrations of EROD inducers in the extracts and therefore proved useful for estimating the contents of Ah receptor ligands in environmental samples.
Environmental chemistry for a surfactant ecotoxicology study supports rapid degradation of C12-alkyl sulfate in a continuous-flow stream Mesocosm
Authors: Guckert James B. , Walker David D. , Belanger Scott E. 
Published: March 2010

Abstract
Environmental chemistry is a vital part of ecotoxicology studies conducted in mesocosms. Quantification of exposure can be particularly challenging for biodegradable surfactants in once-through stream mesocosms like the Procter & Gamble Experimental Stream Facility (ESF). In the fall of 1991, a study was conducted with the anionic surfactant C12-alkyl sulfate (C12-AS). Analysis of chemical feed tank concentrates indicated that the in-stream concentrations should be very close to the nominal concentrations (26, 78, 233, 700, 2, 100 μg/L). However, measured concentrations were lower than expected. The concentrations at the head of the streams were 4 to 23% below nominal concentrations and there was an additional 14 to 33% decline in head to tail C12-AS concentrations. Total residence time in the streams is about 4.3 min. Because analytical losses had been minimized using individual sample recovery factors, it was concluded that these losses were due to rapid C12-AS biodegradation. The results of this analytical program are used to define the in-stream C12-AS concentrations to express subsequent community- and ecosystem-level no-observed-effect concentrations. In addition, the environmental chemistry program described will serve as the model for future programs in support of surfactant ecotoxicology studies conducted at the ESF.
Fish bioturbation of cadmium-contaminated sediments: Factors affecting Cd availability to Daphnia magna
Authors: Wall Steven B. , La Point Thomas W. , Isely J. Jeffrey 
Published: March 2010

Abstract
Benthic fish bioturbation of contaminated sediments is thought to enhance exposure and, potentially, bioaccumulation into planktonic organisms. Exposures were conducted with cadmium-spiked sediment, 1.0 mg/kg nominal concentrations, and koi carp (Cyprinus carpio). Daphnia magna were placed in aquaria with and without fish for 6 d and Cd bioaccumulation was measured every 48 h. Koi carp bioturbation increased mean total suspended solids (TSS) in two trials from 0.001 mg/L to 44.4 mg/L and 19.2 mg/L to 762.4 mg/L. Mean aqueous Cd concentrations increased from 1.4 μg/L to 2.8 μg/L, and from 1.6 μg/L to 13.2 μg/L. Cadmium binding capacity increased from 28.9 μg/L to 169.8 μg/L in with-fish treatments when compared to controls. However, Daphnia magna body burdens did not increase. Mean Cd residues of daphnids exposed with fish, 9.2 μg/g, were not statistically different from without-fish exposures, 8.0 μg/g. Body burdens slightly decreased in the first trial after the with-fish treatment, 9.4 μg/g to 8.3 μg/g. Fish size was partially correlated with TSS and aqueous Cd concentrations and TSS positively correlated with binding capacity. Because increased TSS in the with-fish treatment resulted in increased binding capacity, it is probable that cadmium bioavailability decreased. Although koi carp were capable of remobilizing Cd from sediment, Cd bioaccumulation into Daphnia magna was not significant.
Profile of toxic response to sediments using whole-animal and in vitro submitochondrial particle (SMP) assays
Authors: Bettermann Alan D. , Dorofi Jonathan C. , Lazorchak James M. 
Published: March 2010

Abstract
A rapid bioassay for monitoring acute toxicity of wastewater, ground water, and soil and sediment extracts using submitochondrial particles (SMP) has been developed. The assay utilizes the mitochondrial electron transfer enzyme complex, present in all eukaryotic cells. Prior developmental work with pure chemicals chosen from the U.S. Environmental Protection Agency's (EPA) priority pollutant list documented order-of-magnitude predictability between the bioassay response and whole-organism tests (e.g., fathead minnow). Recent work has adapted the assay for analysis of uncharacterized environmental samples, including stormwater runoff, landfill leachate, and soil and sediment extracts. A feasibility study was performed to determine whether the SMP assay could detect toxicity in samples previously assessed for toxicity to amphipods. Acute toxicity tests using Hyalella azteca were performed on 30 sediment samples from Colorado's Arkansas River, Eagle River, and Chalk Creek watersheds, all of which have been directly or indirectly affected by heavy metal mine tailings and drainage. In parallel, two SMP assay protocols designed to differentiate between modes of toxicity were performed on elutriate samples from 23 of the above sites. The results from analysis of the sediments differed widely in the nature and degree of test responses. Significant correlation was found between the responses of the SMP electron transfer protocol and the whole-organism assay, and between the responses of the SMP electron transfer protocol and levels of zinc and sulfur, as determined by inductively coupled plasma spectroscopy.
Buffers in daphnid culture and bioassay
Authors: Keating Kathleen I. , Caffrey Paula B. , Dagbusan Brenda C. 
Published: March 2010

Abstract
When an algal diet is employed, or precipitation of dissolved inorganics during autoclaving is likely, or test circumstances introduce pH changes, addition of a buffer to daphnid culture or bioassay media is appropriate. Glycylglycine, employed in our research for 20 years, is unsuitable for general use because it requires microbe-free cultures. In contrast, n-hydroxyethyl piperazine-n-2-propane sulfonic acid (HEPPSO) and N-2-hydroxyethyl piperazine-N′-2-ethane sulfonic acid (HEPES) offer safe and effective pH control at 300 ppm for animals, 400 ppm for algae (weight excludes Na), with no requirement for microbe-free cultures. No negative effects on fecundity, monitored in both single and multigeneration tests, or on vigor, measured by acute bioassay performance, were observed. The 48-h LC50 for glycylglycine is approximately 4,500 ppm. No deaths occur at or below 10,000 ppm of either HEPES or HEPPSO. When bioassayed against zinc (as chloride), animals reared in cultures buffered by HEPES, HEPPSO, or glycylglycine and tested in unfed acute bioassays performed similarly, allowing 100% survival in 1,000 ppb in 48 h with an LC50 of approximately 1,750 ppb.
Subchronic sensitivity of one-, four-, and seven-day-old fathead minnow (Pimephales promelas) larvae to five toxicants
Authors: Pickering Quentin H. , Lazorchak James M. , Winks Kelly L. 
Published: March 2010

Abstract
The fathead minnow (Pimephales promelas) larval survival and growth test was used to evaluate the relative sensitivity of 1-, 4-, and 7-d-old larvae to five contaminants, KCl, NaCl, 1-octanol, carbaryl, and benzaldehyde. The no observable effect concentration (NOEC) for survival of the two inorganic compounds, KCl and NaCl, was not affected by age of the larvae. The subchronic valve (SCV) for NaCl was always determined by survival. Hypothesis testing of biomass always gave the same NOEC for the three age groups for each of the two inorganic compounds, and a minimum significant difference (MSD) was always calculable. The effect of 1-octanol on growth was more sensitive than the effect on survival in eight of the nine toxicity tests. Within a set of 1-, 4-, and 7-d-old larvae tests the SCV varied only twofold; however, between sets of tests the variation was fourfold. The SCV of carbaryl was determined by the effect on growth in five of six tests. Except for one test the SCV varied only twofold. The 1-d larvae were more sensitive to benzaldehyde than 1- and 7-d larvae in two sets of tests. The SCV was determined on the basis of survival for 1-d-old larvae and on the basis of growth for 4- and 7-d-old larvae.
A method for assessing sublethal effects of contaminants in soils to the earthworm, Eisenia foetida
Authors: Gibbs Mitchell H. , Wicker Linda F. , Stewart Arthur J. 
Published: March 2010

Abstract
We developed and tested a procedure that allows quantification of the effects of soil contaminants on earthworm (Eisenia foetida) growth and reproduction. The procedure monitors isolated pairs of earthworms and generates a higher ratio of data per organism than other commonly used procedures. It also incorporates an accurate technique for measuring adult growth, has high sensitivity compared to the Organization for Economic Cooperation and Development (OECD) 14-d acute toxicity test, and is cost effective. We applied the method to a variety of soil-testing problems. A food-and-substrate trial using artificial soil demonstrated the sensitivity of the method and the need for food supplementation to stimulate earthworm reproduction. Application of the procedure to assess efficacy of a soil bioremediation technology revealed the advantage of measuring both growth and reproduction and highlighted the usefulness of a single integrated measure of these two responses. The method also was used as a fast-screening analysis for field soils in a large-scale ecological risk assessment. Finally, a reference toxicant, used in dilution series, demonstrated that responses of E. foetida using our method were similar to their responses in the OECD artificial-soil test method. The results of this study indicate that this procedure can be used both for regulatory and compliance needs within the framework of ecological risk assessment.
The effects of land-use characteristics and acid sensitivity on the ecological status of maryland coastal plain streams
Authors: Hall Lenwood W. , Scott Mark C. , Killen William D. , Anderson Ronald D. 
Published: March 2010

Abstract
A 2-year study was conducted to evaluate the ecological status of 12 acid-sensitive and 12 non-acid-sensitive Maryland coastal plain streams during the spring, summer, and fall of 1992 to 1993. An index of biotic integrity (IBI) for fish, chemical parameters, and physical habitat conditions were evaluated in these streams. Correlations of land-use activities (forested streams vs. agricultural dominated streams) and watershed size were identified in the coastal plain streams with biological, chemical, and physical conditions. These data were also used to determine if a poor IBI for coastal plain stream fish can be related to stream sensitivity from acidic inputs.
Physical habitat was more important than water quality in determining IBI values for the 2-year period. Acid sensitivity was also important in influencing the IBI but the influence of acid sensitivity was overshadowed by physical habitat. When variation in physical habitat was accounted for among sites, the IBI in nonacid-sensitive streams was higher than in acid-sensitive streams. Initial results demonstrated that IBI values were higher in agricultural dominated streams when compared to forested streams. Consideration of only two dominant land-use types caused oversimplification of these results because urban land use (often associated with negative effects) was positively correlated with forested streams and negatively correlated with agricultural streams.
Effects of chronic pesticide stress on wildlife populations in complex landscapes: Processes at multiple scales
Authors: Maurer Brian A. , Holt Robert D. 
Published: March 2010

Abstract
Populations exposed to pesticides may often be divided into subpopulations, where some subpopulations are exposed to pesticides and others are not. We consider three models for such populations. The first is a simple discrete time model with no density-dependent reproduction. The second is a continuous time model that includes density-dependence for populations not exposed to pesticides. In both models, populations exposed to pesticides are assumed to decline geometrically (exponentially in the continuous time model). Migration between exposed and safe habitat patches is symmetric, so that all individuals leaving safe patches enter exposed patches and vice versa. The rate is assumed to be the same for both kinds of patches. The conditions for persistence of the population in the landscape are the same for both models. Increasing migration rate between patches decreases the ability of the population to persist. Populations that have low rates of increase in safe habitat patches have greater difficulty persisting than those with high rates of increase in safe patches. The toxicity of the pesticide also affects population persistence. More toxic pesticides that result in higher rates of death and/or lower rates of birth in exposed habitat patches lower the ability of the population to persist in the landscape. We consider an additional set of models of a metapopulations that persist because of a balance between colonization and local extinction. In such systems, pesticides may endanger regional persistence by reducing the pool of sites available for colonization. We conclude with an outline of important future directions for theoretical research intended to elucidate the impact of pesticides on populations spatially complex landscapes.
The layered and historical nature of ecological systems and the risk assessment of pesticides
Authors: Landis Wayne G. , Matthews Robin A. , Matthews Geoffrey B. 
Published: March 2010

Abstract
The community conditioning hypothesis is used as a framework in which to place the layers of effects during and after pesticide intoxication. Community conditioning states that information about the history of a system can be and is written at a variety of organismal and ecological levels. This historical component or etiology determines the future dynamics of a system. The storage of information concerning prior stressor events has been observed in a variety of compartments. Fish populations have been observed to have different genetic structures in populations that have been exposed to toxicant stressors. Analysis of biomarker data from field experiments reveals a variety of patterns, some due to the location of the field plots. Treatment groups within a series of microcosm experiments maintain their identities long after the degradation of the toxicant. The dynamics of the treatment groups in multivariate ecological space are characteristic of a particular treatment. Other microcosm systems differentially respond to invasion depending upon the order of the inoculation of the biotic components, even though at the time of the invasion the systems are indistinguishable. A major factor in the uncertainty of pesticide risk assessment will be the unknown etiology of the system of interest.
Biomonitoring with sentinel plants to assess exposure of nontarget crops to atmospheric deposition of herbicide residues
Authors: Felsot Allan S. , Bhatti Muhammad A. , Mink Gaylord I. , Reisenauer G. 
Published: March 2010

Abstract
In regions of highly diversified agriculture, herbicides used in one field may not be compatible with crops growing in nearby fields. Injury to nontarget crops may occur from drift or localized atmospheric transport of herbicide residues. Pea, bean, and corn seedlings have been used as sentinels to detect atmospheric deposition of trace residues. Seedlings were exposed at various locations throughout south central Washington and exchanged on a weekly basis with a new set of plants. Plants were returned to a lath house and observed over 3 weeks for development of symptoms indicative of probable exposure to four classes of herbicides—sulfonylureas, phenoxyacetates, aminophosphonic acids, and bipyridiliniums. The most frequently observed symptoms on sentinel plants were chlorotic spots on the upper leaf surfaces; such symptoms were created under controlled conditions by exposing plants to aerosols of the sulfonylurea (SU) herbicide chlorsulfuron. For 3 years, the greatest incidence of probable SU symptoms was detected during April; however, occurrence of symptoms was not correlated with periods of maximum use of SU herbicides on wheat in the region. The results suggested a general atmospheric loading of herbicides with occasional deposition, rather than point source drift. Further tests are needed to quantitate the exposures of sentinel plants and determine if chlorotic spots are associated with adverse physiological effects.
Interactions of Cd and Cu in anaerobic estuarine sediments. II. Bioavailability, body burdens and respiration effects as related to geochemical partitioning
Authors: Rule Joseph H. , Alden Raymond W. 
Published: March 2010

Abstract
The relationship between Cd and Cu distribution in sediment geochemical fractions and their bioavailability was studied. A fine-sandy textured estuarine sediment was treated with all combinations of 0, 2.5, and 5 mg/kg Cd and 0, 12, and 25 mg/kg Cu using the chloride salts of each metal. Grass shrimp (Palaemonetes pugio), blue mussel (Mytilus edulis), and hard clam (Mercenaria mercenaria) were exposed to the treated sediments in aquaria with 20 ppt artificial seawater for 14 d. Sediments were sequentially extracted before and after organism exposure to determine the exchangeable, easily reducible, organic-sulfide, moderately reducible, and acid extractable phases. Low mortalities were observed for all organism types and none were attributable to any of the treatments. The Cd and Cu concentrations in the easily reducible and organic-sulfide phases were found to be significantly related to the bio-availability of these metals. The most highly significant relationship was established between Cd in the easily reducible phase and body burden of Cd in the blue mussel. Notable interactions were found between Cd and Cu in some of the geochemical phases, body burdens, and respiration rates. Metal uptake, respiration, and interactions were highly dependent on the test species. A significant correlation was found between increased body burden and depressed respiration for Cd but not for Cu. Multiple regression models are used to describe these relationships. It appears that the interactive responses in the organisms are driven primarily by the sediment geochemical effects and mediated by individual organism processes. These results underscore the necessity of multicomponent (multielement) studies in assessing the fate and effects of toxic elements in the environment.
Comparative response of Ceriodaphnia dubia and juvenile Anodonta imbecillis to pulp and paper mill effluents discharged to the tennessee river and its tributaries
Authors: McKinney Aubrey D. , Wade Donald C. 
Published: March 2010

Abstract
The responses of Ceriodaphnia dubia (daphnid) in a 7–d chronic daily-renewal bioassay and 6–d-old juvenile Anodonta imbecillis (paper pondshell mussel) in a 9–d acute daily-renewal bioassay are compared. Values for relative sensitivity to selected complex, industrial, whole-effluent samples were generated following determination of either observed or calculated no-observable-effect concentrations (NOEC). Results from tests using effluents from six pulp and paper products facilities in the Tennessee River Valley indicate that A. imbecillis juveniles are substantially more sensitive than C. dubia to selected effluents. It is suggested that a juvenile mussel bioassay should be used to assess the toxicity of effluent releases to waters with freshwater mussel resources.