bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bioaccumulation of metals by Hyalella azteca exposed to contaminated sediments from the upper clark fork river, montana
Authors: Ingersoll Chris G. , Brumbaugh William G. , Dwyer F. James , Kemble Nile E. 
Published: March 2010

Abstract
Macroinvertebrates contaminated with metals in the Clark Fork River of Montana have been demonstrated to be a potentially toxic component in the diet of trout Because sediment was the suspected source of metals to these invertebrates, bioaccumulation of As, Cd, Cu, Pb, and Zn from sediment was evaluated by exposing the amphipod Hyalella azteca for 28 d in the laboratory to samples of sediment collected from depositional areas of the Clark Fork River Benthic invertebrates collected from riffles adjacent to the depositional areas were also analyzed for metals The pattern of metal accumulation between laboratory-exposed and field-collected animals was similar, however, the concentrations of metals in laboratory exposed amphipods were often 50 to 75% less than were the concentrations of metals in the field collected invertebrates These findings indicate that sediment is a significant source of metals to invertebrates in the Clark Fork River Additional studies should be conducted to determine threshold concentrations for effects of dietary metals on fish Long-term monitoring of the river should include sampling benthic invertebrates for metal accumulation
Dietary and waterborne exposure of rainbow trout (Oncorhynchus mykiss) to copper, cadmium, lead and zinc using a live diet
Authors: Mount David R. , Barth Anita K. , Garrison Tyler D. , Barten Karen A. , Hockett J. Russell 
Published: March 2010

Abstract
In two 60 d exposures, rainbow trout fry were fed brine shrimp (Artemia sp) enriched with Cu, Cd, Pb, and Zn both individually and as a mixture combined with As Dietary concentrations fed to trout were selected based on metal concentrations measured in invertebrates collected from the Clark Fork River (CFR), Montana In addition to dietary exposure, treatments also included simultaneous exposure to a mixture of waterborne metals at sublethal concentrations Fish in all treatments showed increased tissue metal concentrations from water and/or dietary exposure Despite these accumulations, trout showed no effects on survival or growth from dietary concentrations as high as 55 μg Cd/g dry weight, 170 μg Pb/g dry weight, or 1,500 μg Zn/g dry weight (corrected for depuration) Dietary Cu concentrations up to 350 μg Cu/g dry weight did not reduce survival or growth Fish fed Cu concentrations higher than those typical of CFR invertebrates (660 and 800 μg Cu/g dry weight, corrected for depuration) showed about 30% mortality with no effect on growth, waterborne Cu released from Artemia may have contributed to this mortality Trout exposed to diets with a mixture of Cu, Cd, Pb, Zn, and As close to that measured in CFR invertebrates showed lower weight than did control fish after 35 d, but this difference was no longer present after 60 d
Characterization of ecological risks at the milltown reservoir-clark fork river sediments superfund site, montana
Authors: Pascoe Gary A. , Blanchet Richard J. , Linder Greg , Palawski Don , Brumbaugh William G. , Canfield Tim J. , Kemble Nile E. , Ingersoll Chris G. , Farag Aïda , Dalsoglio Julie A. 
Published: March 2010

AbstractA comprehensive field and laboratory approach to the ecological risk assessment for the Milltown Reservoir-Clark Fork River Sediments Site, a Superfund site in the Rocky Mountains of Montana, has been described in the preceding reports of this series. The risk assessment addresses concerns over the ecological impacts of upstream releases of mining wastes to fisheries of the upper Clark Fork River (CFR) and the benthic and terrestrial habitats further downstream in Milltown Reservoir. The risk characterization component of the process integrated results from a triad of information sources: (a) chemistry studies of environmental media to identify and quantify exposures of terrestrial and aquatic organisms to site-related contaminants; (b) ecological or population studies of terrestrial vegetation, birds, benthic communities, and fish; and (c) in situ and laboratory toxicity studies with terrestrial and aquatic invertebrates and plants, small mammals, amphibians, and fish exposed to contaminated surface water, sediments, wetland soils, and food sources. Trophic transfer studies were performed on waterfowl, mammals, and predatory birds using field measurement data on metals concentrations in environmental media and lower trophic food sources. Studies with sediment exposures were incorporated into the Sediment Quality Triad approach to evaluate risks to benthic ecology. Overall results of the wetland and terrestrial studies suggested that acute adverse biological effects were largely absent from the wetland; however, adverse effects to reproductive, growth, and physiological end points of various terrestrial and aquatic species were related to metals exposures in more highly contaminated depositional areas. Feeding studies with contaminated diet collected from the upper CFR indicated that trout are at high risk from elevated metals concentrations in surface water, sediment, and aquatic invertebrates. Integration of chemical analyses with toxicological and ecological evaluations of metal effects on the wetland and fishery has provided an important foundation for environmental decisions at this site.
Contact toxicity of metals in sewage sludge: evaluation of alternatives to sodium chloride in the microtox® assay
Authors: Carlson-Ekvall C. E. Annika , Morrison Gregory M. 
Published: March 2010

Abstract
The presence of chloride ions in the Microtox® test can cause problems when testing metal toxicity, both due to extraction of metals from solid samples and formation of chloro complexes of metals in the liquid phase. To investigate alternatives to NaCl in the Microtox test, the toxicity of Cu, Cd, Pb, and Zn to Photobacterium phosphoreum was tested in 28 osmotic surrogates for NaCl. It was found that Na+ must be present to keep the blank luminescence stable for 30 min. The results point to NaClO4 as the most satisfactory surrogate solution as it has an inert behaviour and does not form complexes with any metal of environmental interest. Raw, digested, and reference sewage sludges were tested in the osmotic surrogates. The EC50 values for sludges were lower in solutions of NaNO3, Na2SO4, and NaClO4, and higher in sucrose, mannitol, and KCl, compared to NaCl. NaClO4 can be recommended as an osmotic surrogate for sewage sludge testing. Another problem with the Microtox assay is the lack of pH control in the cuvette. Copper toxicity tests were carried out in Tris buffer and KH2PO4 at two different concentrations and at pH 7 and 8. The results show that 1 mM phosphate buffer, pH 7.0, can be recommended for solid samples. However, owing to formation of KClO4 a buffer containing potassium is not recommended in combination with NaClO4.
Behavioral responses of Daphnia pulex exposed to carbaryl and Chaoborus kairomone
Authors: Dodson Stanley I. , Hanazato Takayuki , Gorski Patrick R. 
Published: March 2010

Abstract
An analysis of digitized three-dimensional video records of free-swimming Daphnia pulex identified six measurements of swimming behavior that can be used to quantify individual behavioral responses to pesticides or natural chemical signals. Protocols are given for measuring the parameters that showed statistically significant changes in pesticide treatments. The most efficient experimental design would involve observing as many animals as possible, with one observation per animal. Parameters most likely to be useful in future studies are velocity, turning angle, upward and downward angles during hops, variance in vertical position, and hopping frequency. The parameters varied in usefulness, defined as the ratio of within-treatment to among-treatment variance (F ratios). Velocity was the most useful (i.e., had the highest F ratio); hopping frequency was the least useful. Daphnia exhibited three kinds of swimming behavior, as defined by eight parameters: (a) “spinning” (extreme and continuous escape response) to acutely toxic levels of Carbaryl (40 ppb); (b) “irritation” (an increase in escape-like behavior) to low levels of Carbaryl (1 ppb); and (c) “null” behavioral responses to Chaoborus-conditioned water, in which there was no detectable change in any measurement of swimming behavior. In predation trials, bluegill sunfish preferentially selected individuals showing “spinning” behavior. Results from this and other studies of Daphnia swimming behavior suggest a conservative-swimming hypothesis for understanding constraints on Daphnia swimming behavior.
Development and field validation of a microcosm to simulate the mercury cycle in a contaminated pond
Authors: Saouter Erwan , Gillman Mark , Turner Ralph , Barkay Tamar 
Published: March 2010

Abstract
A microcosm consisting of water, sediment, and air compartments was used to simulate mercury geochemical cycling in a mercury-contaminated (μg L−1) pond at Oak Ridge, Tennessee. Total and dissolved mercury and total methylmercury were analyzed in water and sediment; total gaseous mercury and head-space mercury were analyzed in the water and head space, respectively. The production of gaseous mercury was correlated to dissolved mercury (0.2-μm filtration), and methylmercury was mainly produced in the sediment compartment. Addition of mercuric chloride to the system increased the production of head-space mercury by a factor of 10 but did not affect the methylation rate. Saturation of gaseous mercury in microcosm water varied from 480 to 1,500% of the solubility of elemental mercury and was controlled by unidentified factors. The microcosm maintained stable conditions for up to 3 weeks, and a mass balance indicated that it reasonably simulated the cycling of mercury in the pond. This microcosm could be used to test remedial treatments aimed at decreasing the amount of mercury that is available for accumulation by biota.
Identification of potential fish carcinogens in sediment from hamilton harbour, ontario, canada
Authors: Balch G.C. , Metcalfe C.D. , Huestis S.Y. 
Published: March 2010

Abstract
A carcinogenicity- and mutagenicity-directed fractionation approach was used to identify the carcinogenic compounds in contaminated sediments that are putatively responsible for the high prevalence of tumors in bottom-dwelling fish from Hamilton Harbour, Ontario. Mutagenic activity was detected with Ames tester strains (TA98, TA100) in relatively nonpolar fractions of sediment extract containing PAHs and nitrogen-containing aromatic compounds (NCACs). These fractions were also carcinogenic in an in vivo carcinogenicity bioassay with rainbow trout (Oncorhynchus mykiss). When a more polar extract fraction was tested for mutagenicity and carcinogenicity, weak mutagenic activity was detected with an O-acetyltransferase-enriched Ames tester strain (YG1024), and weak carcinogenic activity was detected in the rainbow trout assay. These data indicate that PAHs in contaminated Hamilton Harbour sediments are potent fish carcinogens, but it is also evident that other organic compounds in the sediment, such as NCACs and nitroarenes, may contribute to carcinogenicity.
The role of acid-volatile sulfide and interstitial water metal concentrations in determining bioavailability of cadmium and nickel from contaminated sediments to the marine polychaete Neanthes arenaceodentata
Authors: Pesch Carol E. , Hansen David J. , Boothman Warren S. , Berry Walter J. , Mahony John D. 
Published: March 2010

Abstract
This study investigated the influence of acid-volatile sulfide (AVS) and interstitial water (IW) metal concentrations on bioavailability and toxicity of Cd and Ni to an infaunal sediment-ingesting marine worm, Neanthes arenaceodentata. Ten-d exposures were conducted with sediments, contaminated primarily with Cd and Ni, from Foundry Cove (Hudson River, NY), and with uncontaminated sediments spiked with Cd or Ni. Molar ratios of simultaneously extracted metal (SEM)/AVS ranged from &lt;0.02 to 44 for Cd-spiked, 0.02 to 241 for Ni-spiked, and &lt;0.06 to 125 for Foundry Cove sediments. In all experiments, significant mortality was not observed when SEM/AVS ratios were &lt;1.0 and interstitial water toxic units (IWTU) were &lt;1.0 (toxic unit = IW metal concentration/LC50 value of water-only exposure). In the Cd and Ni-spiked experiments, when SEM/AVS ratios or IWTUs were &gt;1.0, sediments were either lethal or worms did not burrow. Mortality of worms in Foundry Cove sediments was ≤20%, and worms burrowed in all these sediments. However, IW contained &lt;1.0 TU (Ni + Cd) in all Foundry Cove sediments except one (IWTU = 1.69). Metal concentrations in worms generally increased with increases in sediment metal concentration, SEM/AVS molar ratio, and IW metal concentration. The presence of metal in worms from sediments with SEM/AVS ratios &lt;1.0 may be evidence of release of Cd or Ni from oxidized metal sulfide (a result of burrowing), uptake of metal from ingested sediment, or adsorption to body surfaces. These results support the hypothesis that when the concentration of AVS in sediments exceeds that of divalent metals (Cd, Cu, Hg, Ni, Pb, Zn) sediments will not be acutely toxic. However, a greater number of sediments was correctly predicted to be nontoxic when interstitial water metal concentration of &lt;1.0 TU was used.
A field evaluation of cytochrome P4501A as a biomarker of contaminant exposure in three species of flatfish
Authors: Collier Tracy K , Anulacion Bernadita F , Stein John E , Varanasi Usha , Goksøyr Anders 
Published: March 2010

AbstractA study was conducted over the course of a year to determine the induction of hepatic cytochrome P4501A (CYP1A) in three species of benthic fish collected from a contaminated site compared to fish sampled from a less-contaminated site Juvenile fish were used to minimize effects of reproductive status and migration CYP1A was determined by two catalytic assays [aryl hydrocarbon hydroxylase (AHH) and ethoxyresorufin O deethylase (EROD)] and by an immunoassay (ELISA) utilizing polyclonal antibodies raised against purified CYP1A from cod AHH activities were measured by a standard method (AHHstd) and by two variations of the standard method All three primary CYP1A measures (AHHstd, EROD, and ELISA) showed consistent between site differences, indicating that induction of CYP1A can be a reliable biomarker of contaminant exposure in fish if appropriate biological variables are controlled for in field studies Multiple ANOVA demonstrated that the AHHstd and ELISA data showed less variability due to species or temporal differences, and less unexplained variability, compared to the data from the EROD assay or either variation of the AHH assay For all measures, variability associated with site differences far outweighed species or temporal variability Immunoassay, while less sensitive than the AHHstd assay, is nonetheless recommended to be used in conjunction with catalytic assays because of the potential for samples to lose catalytic activity if not handled properly The current results suggest that the lower noncontaminant related variability of AHHstd makes this CYP1A measure potentially more useful for monitoring programs in which analysis of trends is a primary goal
Seasonal variation in the mixed-function oxygenase system and antioxidant enzymes of the mussel Mytilus galloprovincialis
Authors: Solé M. , Porte C. , Albaigés J. 
Published: March 2010

Abstract
Seasonal variations in the mixed-function oxygenase (MFO) system components (cytochrome P450, “418” peak, and NADPH-cytochrome c[P450] reductase) and antioxidant enzymes (catalase, superoxide dismutase [SOD], glutathione peroxidase [GPX], and DT-diaphorase) of the mussel Mytilus galloprovincialis have been evaluated. Its relation with contaminant body burden (PAHs, PCBs, DDTs, and lindane) as well as environmental parameters (water temperature, salinity, oxygen concentrations, and suspended matter) was determined. As a general trend, low MFO and antioxidant enzyme activities were detected in February-March, a peak in late April, and a gradual decrease with a minimum in June. This pattern was similar to tissue concentrations of PAHs, PCBs, DDTs, and lindane normalized to lipid weight. Cytochrome P450 content, however, exhibited a steady decrease from February to June. The observed seasonal variations are presumably related to the metabolic status of the animal, itself dependent on such factors as gonadal ripening, food availability, and the hydrological cycle, which regulates productivity in the area.
A modeling procedure to evaluate the coherence of independently derived environmental quality objectives for air, water and soil
Authors: van de Meent D. , de Bruijn J.H.M. 
Published: March 2010

Abstract
Sets of independently derived environmental quality objectives (EQOs) for air, water, and soil may not be coherent in that maintaining the concentration at EQO level in one compartment may lead to exceeding EQO levels in other compartments. A methodology to evaluate this coherence is suggested. Starting from a steady concentration in the compartment of focus (the primary compartment), steady-state concentrations in the adjacent (secondary) compartments are estimated using a multimedia fate model. If air is the primary compartment, steady-state concentrations in water and soil close to the equilibrium concentrations can be expected, and coherence of EQOs can be evaluated easily by means of an extended equilibrium partitioning procedure. If water or soil is the primary compartment, the steady-state concentration in air is usually well below the equilibrium concentration. Subequilibrium steady-state concentrations are sensitive to assumed model parameters. The procedure is illustrated with the results of a coherence analysis for seven chemicals for The Netherlands.
Enrichment of biogenic lipids, hydrocarbons and PCBs in stream-surface foams
Authors: Napolitano Guillermo E. , Richmond Jacqueline E. 
Published: March 2010

Abstract
Water and foam samples from five streams in eastern Tennessee were analyzed for lipid content, lipid-class composition, and polychlorinated biphenyls (PCBs). Total lipid contents and lipid-class compositions varied substantially among streams and between the water and foam fractions within streams. However, lipid contents in foams were always greater than in the water from the same site (up to 100-fold). Major lipid classes in the water and foam samples were phospholipids, free fatty acids, and hydrocarbons; these lipid classes indicate the stream status with respect to viable microbial biomass, organic decay, and petroleum pollution, respectively. Concentrations of PCBs in stream-water and foam samples were also measured, and a laboratory experiment using stream water, reconstituted natural foam, and Aroclor 1254 was conducted to assess partition ratios of PCBs for water and foam. The results of the field and laboratory studies showed that the foam concentrated PCBs (relative to the parent waters) by factors of up to 10. The concentration of biogenic lipids and lipophilic pollutants in natural foams may influence the downstream transport of pollutants and affect their bioavailability to stream organisms.
Facile synthesis and physical and spectral characterization of 2,6-di-tert-butyl-4-nitrophenol (DBNP): A potentially powerful uncoupler of oxidative phosphorylation
Authors: Rivera-Nevares José A. , Wyman John F. , Von Minden David L. , Lacy Nathan , Chabinyc Michael L. , Fratini Albert V. , Macys David A. 
Published: March 2010

Abstract
The compound 2,6-di-tert-butyl-4-nitrophenol (DBNP), a potentially powerful uncoupler of ATP-generating oxidative phosphorylation, has been physically and spectroscopically characterized using X-ray crystallography, differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), GC-MS spectrometry, Fourier-transformed IR (FTIR) spectrophotometry, UV-Vis spectrophotometry, and FT 1H- and 13C-NMR spectroscopy. However, DBNP is not commercially available; therefore, it had to be synthesized in the laboratory prior to toxicity studies. The DBNP was prepared from 2,6-di-tert-butylphenol (DBP) precursor in hexane through an electrophilic aromatic substitution process using NO2. A collective yield of 75% was obtained by using two empirically determined end points that prevented the coprecipitation of reaction by-products and resulted in the formation of DBNP in high purity. Excessive amounts of NO2 in reaction mixtures resulted in the decomposition of preformed DBNP. With a pKa value of 6.8 and a higher degree of lipophilicity, DBNP may prove to be a stronger uncoupler of oxidative phosphorylation than 2,4-dinitrophenol (pKa = 4.09) due to the expected enhancement of passive-diffusion kinetics across biological membranes at the physiological pH of 7.4. The present study is intended to provide analytical toxicologists, industrial hygiene monitors, and other professionals involved in chemical health and safety with a comprehensive source of basic information on the synthesis and analytical chemistry of DBNP.
Uptake, metabolism and toxicity of terbufos in the earthworm (Lumbricus terrestris) exposed to counter®-15G in artificial soils
Authors: Cobb G P , Hol E H , Allen P W , Gagne J A , Kendall R J 
Published: March 2010

AbstractEarthworms (Lumbricus terrestris) were exposed to COUNTER® 15G in artificial soils for 32 d in four treatment blocks Simulated rainfall and temperatures were used to approximate conditions during planting time in the U S corn belt Maximum mean uptake of terbufos was noted on the 8th d following pesticide treatment Terbufos sulfoxide uptake by earthworms was higher than terbufos uptake, and the concentration maximum was observed on day 16 post application Maximum concentrations of terbufos sulfone were detected in earthworm tissues on day 32 post application No significant earthworm mortality was observed on any single collection date, but temporal differences in mortalities were noted between control and treatment groups Total concentrations of terbufos and oxidative metabolites in L terrestris substantiate existing residue data from field investigations
A semistatic microplate-based phytotoxicity test
Authors: Radetski Claudemir Marcos , Ferard Jean-François , Blaise Christian 
Published: March 2010

Abstract
A novel phytotoxicity test is described herein that employs a microplate equipped with membrane-bottomed wells. This MultiScreen™ (Millipore Corp., Bedford, MA) microplate allows performance of a semistatic algal test, in which test medium is renewed periodically. With such a design, the algal test becomes comparable to other short-term tests used to evaluate chronic toxicity of chemicals and effluents. The EC50s obtained for Cu2+, Cd2+, Cr6+, atrazine, and one leachate sample (municipal sludge incinerator residue) with static and semistatic algal microplate tests were compared in this study. The semistatic microplate test revealed greater sensitivity than did the static microplate test.
PCB congeners and hexachlorobenzene biota sediment accumulation factors for Macoma nasuta exposed to sediments with different total organic carbon contents
Authors: Boese Bruce L. , Winsor M. , Lee H. , Echols S. , Pelletier J. , Randali R. 
Published: March 2010

Abstract
Deposit-feeding marine clams (Macoma nasuta) were exposed for 119 d to three sediment types that varied in total organic carbon (TOC) from 0.8 to 2.5%. Sediments were spiked with equal concentrations of 13 polychlorinated biphenyl congeners and hexachlorobenzene. Tissue residues were measured, and steady-state bioaccumulation factors (BAFs), the corresponding lipid, and TOC-normalized biota sediment accumulation factors (BSAFs) were determined. The BSAFs were less variable than were the BAFs with the exception of compounds with log Kow &gt; 7. Many of the BSAFs exceeded 1.7, which is a calculated maximum value based on partitioning alone. Although BSAFs varied with sediment type and compound, the use of a BSAF of 4 as a screening level for neutral organic compounds in assessing dredge materials is supported by the present study.