bluuebunny/crossref_metadata_2025_split huggingface dataset:
Concentrations of selenium, mercury, and lead in blood of emperor geese in western Alaska
Authors: Franson J Christian , Schmutz Joel A , Creekmore Lynn H , Fowler Ada C 
Published: March 2010

Abstract
We found up to 10 ppm wet weight of selenium in blood samples collected from emperor geese (Chen canagica) on their breeding grounds on the Yukon-Kuskokwim Delta in western Alaska, USA. Incubating adult females captured in late May through mid-June 1997 had significantly higher concentrations of selenium in their blood (mean = 5.60 ppm) than adult females captured during wing molt in late July 1996 (mean = 2.78 ppm). Females that nested early or were in good body condition had higher concentrations of selenium in their blood than did other nesting females. Blood samples from 4 of 29 goslings had detectable levels of selenium (mean = 0.14 ppm). Our findings suggest that emperor geese are exposed to more selenium in the marine environment of their wintering and staging areas on the Alaska Peninsula than on the breeding grounds. The highest concentration of mercury found in the blood of emperor geese was 0.24 ppm. One bird had a blood lead concentration of 0.67 ppm, but 82% had no detectable lead in their blood, suggesting that lead exposure from the ingestion of lead shot poses little threat for emperor geese in western Alaska, contrary to findings reported for sympatric spectacled eiders (Somateria fischeri).
Effect of high aluminum consumption on mechanics and composition of furculae of free-ranging coots
Authors: Hui Clifford A , Ellers Olaf 
Published: March 2010

Abstract
High levels of ingested Al can affect mechanical properties of bones. Because of the spring action of the furcula during the wingbeat, small changes in the mechanical properties of this bone may have measurable impacts on long-distance flight. We examined the furculae and ingesta of free-ranging American coots (Fulica americana) in San Francisco Bay (California, USA), where they consume a diet high in Al. We measured the spring stiffness and phase angle (δ) of the furculae and the concentrations of Al, Ca, F, Mg, and P in both the furculae and ingesta. The ingesta had mean Al concentrations (2,384 μg/g, dry weight) and Al:P molar ratios (6.4:1) predicted to affect bone integrity but the bone concentrations of Al were near the normal range and the furcula stiffness did not change with Al concentration. The tan δ of the furculae changed with Al concentration but the relationship was weak. The chemical speciation of the ingested Al may have affected its physiologic role and the high mean levels of ingested calcium (71,283 μg/g, dry weight) very likely neutralized the activity of the Al. Controlled feeding studies have shown that F strengthens avian bones. The bones in our study had molar concentrations of F more than two orders of magnitude greater than Al (170:1) but F appears to have insignificant influence on bone mechanics. The coots in San Francisco Bay apparently are not suffering furcula impairment despite a diet high in Al.
Biochemicall and ultrastructural changes in the liver of baltic salmon SAC FRY suffering from high mortality (M74)
Authors: Pesonen Maija , Andersson Tommy B , Sorri Virpi , Korkalainen Merja 
Published: March 2010

AbstractA high percentage of feral Baltic salmon suffers from an abnormal type of sac fry mortality, designated as the M74 syndrome. Although the cause of the mortality is not known, it has been proposed that a high burden of lipophilic xenobiotics is a contributing factor. The objective of the present study was to investigate hepatocyte ultrastructure and liver biochemical anomalies that could be related to exposure to lipophilic xenobiotics in feral Baltic salmon sac fry. Electron microscopy of M74 sac fry liver revealed a dilatation of endoplasmic reticulum, numerous myelin figures, some swelling mitochondria, and an accumulation of lipid droplets. The ratio of reduced glutathione to oxidized glutathione content in M74 sac fry liver was about 60% of that found in the control sac fry liver. Glutathione reductase, an enzyme responsible for reducing oxidized glutathione to reduced glutathione (GSH), was elevated in the M74 sac fry liver, indicating an adaptive response to an increased demand for GSH. Hepatic glutathione S-transferase activity was significantly higher in the M74-affected sac fry liver compared with that of the normally developing sac fry liver, whereas glutathione peroxidase activity was at about the same level in the two groups. Hepatic cytochrome P4501A (CYP1A) activity and protein content and NADPH cytochrome c reductase activity were higher in the liver of M74 sac fry than in the liver of normally developing sac fry. Anti-trout LMC2 (CYP2K1) recognized two protein bands, one of which was elevated in the M74 sac fry liver. In conclusion, the damage and biochemical changes recorded here, in combination with poor vitamin status in the M74 sac fry, may contribute substantially to the mortality.
Chronic effects of atrazine on tolerance of a benthic diatom
Authors: Nelson Karen J , Hoagland Kyle D , Siegfried Blair D 
Published: March 2010

Abstract
The effects of prior chronic exposure to atrazine on responses to subsequent acute exposures were investigated using a common benthic diatom. Clonal, axenic cultures of Craticula cuspidata were established from the Platte River (Nebraska) and obtained from a culture collection (unlikely prior exposure to atrazine). All cultures received a chronic 67-d treatment of 1 μg/L atrazine, and growth was monitored using fluorometric detection of chlorophyll a. Chronic atrazine exposure significantly reduced growth rate only during the first day of treatment (p = 0.0001); no significant effect was detected throughout the remainder of the 67-d period. Following the chronic treatment, clones were exposed to six atrazine concentrations (83, 188, 402, 860, 1,782, and 3,250 μg/L) to ascertain whether prior exposure influenced the tolerance of this diatom. Prior chronic exposure had a negative effect on growth following subsequent exposures to higher concentrations. A significant decline in growth was detected on days 7, 9, and 12 between previously exposed and control clones at 83 μg/L of atrazine. The lack of increased tolerance in C. cuspidata after a realistic chronic exposure indicates that the levels of atrazine presently found in many lotic systems may inhibit the growth of periphyton during periods of higher pulses of atrazine characteristic of spring runoff events.
Effects of 3,3′,4,4′,5,5′-hexachlorobiphenyl on cytochrome P4501A and estrogen-induced vitellogenesis in rainbow trout (Oncorhynchus mykiss)
Authors: Donohoe Regina M , Wang-Buhler Jun-Lan , Buhler Donald R , Curtis Lawrence R 
Published: March 2010

AbstractEstrogen-regulated synthesis of vitellogenin (Vg), a yolk-protein equired for reproduction, was monitored to explore the potential antiestrogenic effects of the coplanar polychlorinated biphenyl (PCB), 3,3′,4,4′,5,5′-hexachlorobiphenyl (3,4,5-HCB), in juvenile rainbow trout (Oncorhynchus mykiss). The effects of 17β-estradiol on 3,4,5-HCB induction of cytochrome P4501A (CYP1A) were also examined. Trout were injected with 3,4,5-HCB (0.25, 2.5, 25, 50, or 100 mg/kg) or a vehicle control, and after 10 weeks, they were sampled or injected with 17β-estradiol (0.1 mg/kg). Markers of vitellogenesis, such as liver somatic index, hepatic estrogen-binding sites, and plasma Vg concentrations, in 17β-estradiol-treated fish were not affected by 3,4,5-HCB. Maximal induction of CYP1A protein and mRNA occurred at doses above 2.5 mg/kg, and 17β-estradiol reduced CYP1A protein content at a single dose (0.25 μg 3,4,5-HCB/kg). Ethoxyresorufin-O-deethylase (EROD) activity was induced by 3,4,5-HCB doses of between 0.25 and 2.5 mg/kg, but induction was reduced at higher doses, indicating that 3,4,5-HCB suppressed CYP1A catalytic activity. In 3,4,5-HCB/17β-estradiol—treated fish, plasma estradiol was significantly reduced at 100 mg 3,4,5-HCB/kg, but the depression was not associated with CYP1A induction or with other antiestrogenic effects. Although CYP1A was induced, 3,4,5- HCB did not interfere with vitellogenesis, which suggests that the PCB congener is not a potent antiestrogen in rainbow trout.
Remediating hexahydro-1,3,5-trinitro-1,2,5-trazine-contaminated water and soil by fenton oxidation
Authors: Bier Eleanor L , Singh Jasbir , Li Zhengming , Comfort Steve D , Shea Patrick J 
Published: March 2010

Abstract
Soils surrounding the former Nebraska Ordnance Plant (NOP) and other military installations are highly contaminated with hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). Because RDX is mobile in soil and recalcitrant at high concentrations, soil remediation is needed to reduce environmental hazards. Conventional treatment by incineration is costly and often creates strong public opposition. We propose an alternative treatment using the Fenton reagent (Fe2 + H2O2) to remediate RDX-contaminated water and soil. Treating an aqueous solution of RDX with the Fenton reagent resulted in complete RDX destruction within 24 h. Ultraviolet irradiation in combination with Fenton reagent enhanced both RDX transformation and mineralization. Mass balance experiments with 14C-RDX indicated that, within 12 h of Fenton oxidation, 76% of the initial 14C activity was lost from solution, the majority of which (68%) was recovered as 14CO2. Additional products resulting from Fenton oxidation of RDX included NH+4, NO−3, and formic acid; we also present evidence that methylene dinitramine is formed. The U.S. EPA remediation goal (5.8 mg RDX/kg) for the NOP site was achieved when the Fenton reagent was added incrementally to RDX-contaminated soil slurries at elevated temperature (45°C). These results support the use of the Fenton reaction for remediating RDX-contaminated water and soil.
Aqueous solubility, octanol solubility, and octanol/water partition coefficient of nine hydrophobic dyes
Authors: Sijm Dick T H M , Schüürmann Gerrit , de Vries Pieter J , Opperhuizen Antoon 
Published: March 2010

AbstractThe aqueous solubilities (Sw), the octanol/water partition coefficients (Kow), and the solubilities in octanol (Soct) of a series of nine hydrophobic anthraquinone and azo dyes have been experimentally determined. Some dyes show more than one aqueous solubility, which is probably due to their polymorphic crystalline forms. Sw ranged from 1 μg/L to 1 mg/L, the log Kow ranged from 3.6 to &gt; 5.8, and Soct ranged from 10 to 3,000 mg/L. The dyes are not only hydrophobic but lipophobic as well. The most important finding is that there is a discrepancy between the Kow and the ratio Soct/Sw for the dyes, while there is a relatively good relationship between either Sw or Soct and the ratio Soct/Sw. The discrepancy probably explains why estimated values of Sw and Kow generally underestimated the experimental ones and that none of the calculated molecular properties (molecular weight, surface area, and volume) was highly correlated to either Sw or Kow. The results show that insufficient knowledge is available to understand and predict the magnitude of the physicochemical properties of the dyes. Therefore, these properties should be preferably experimentally determined.
Fate of a metal-resistant inoculum in contaminated and pristine soils assessed by denaturing gradient gel electrophoresis
Authors: Stephen John R , Chang Yun-Juan , Macnaughton Sarah J , Whitaker S Leigh , Hicks Christopher L , Leung Kam T , Flemming Cecily A , White David C. 
Published: March 2010

Abstract
Cesium, cadmium, cobalt, and strontium are four contaminants frequently found in soils at biotoxic levels. Introduction of certain nongenetically modified bacteria has been frequently suggested as a method for the immobilization of heavy metal contaminants in soil, thereby reducing runoff and bioavailability. In this study, we have used the polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) to track the survival of five bacterial species added to soil microcosms with and without the addition of a mixture of these metals. The PCR primers targeted conserved regions of the 16S rDNA molecule present in all bacteria. The reaction products were shown to reflect the relative abundance of the bacteria both in mixtures of pure cultures and against a background of all the eubacterial species present in the soil following inoculation. Three of the species (Pseudomonas aeruginosa FRD-1, Shewanella putrifaciens 200, and Desulfovibrio vulgaris Hildenborough) decreased rapidly following inoculation into both soils. The proportion of Alcaligenes eutrophus CH34 remained at a constant level throughout the 8-week experiment in both soil treatments. Sphingomonas aromaticivorans B0695 showed toxic metal-dependent survival in that its relative abundance dropped rapidly in pristine soil but remained at approximately inoculation levels throughout the experiment in contaminated microcosms.
Genotoxicity of two polycyclic aromatic hydrocarbons declines as they age in soil
Authors: Alexander Renee R , Alexander Martin 
Published: March 2010

AbstractRifampicin-resistant mutations were induced in Pseudomonas putida A11rUV growing in soil containing 9,10-dimethyl-1,2-benzanthracene and benzo[a]pyrene. Aging of the compounds for 7 d caused a marked decrease in the mutation rates, and the number of mutants was further reduced after 15 d of aging. Longer persistence of the compound in soil did not further diminish the number of mutants. Vigorous solvent extraction showed that the concentration of the compounds had not diminished with the marked decline in genotoxicity. The data demonstrate that genotoxicity of such compounds aged in soil declines with little or no loss of the compound.
Three-phase modeling of polycyclic aromatic hydrocarbon association with pore-water-dissolved organic carbon
Authors: Mitra Siddhartha , Dickhut Rebecca M 
Published: March 2010

Abstract
Log–log plots of measured organic carbon-normalized sediment pore-water distribution coefficients (K′OCS) for several polycyclic aromatic hydrocarbons (PAHs) versus their octanol-water partition coefficients (K′owS) at two sites in the Elizabeth River, Virginia, show large deviations from linearity. Organic-carbon normalized distribution coefficients for these PAHs between sediments and pore waters decreased by more than two orders of magnitude with depth as well. To determine to what extent pore water dissolved and colloidal organic carbon (DOC) was responsible for the observed nonlinearity and decrease in K′OC, a three-phase model was used to estimate pore-water PAH-DOC binding coefficients (KDOC). Partitioning of PAHs to pore-water DOC (i.e., KDOC) enhances the observed “dissolved” phase PAH concentration, especially for high-Kow compounds, contributing to the nonlinearity in K′OC-Kow plots. However, our application of the three-phase partitioning model to these data indicate that, at most, pore-water PAH-DOC binding accounts for one order of magnitude of the observed decrease in K′OC with depth in the sediment bed. The results of this study are consistent with three-phase partitioning theory for hydrophobic organic compounds between sediment organic matter, pore-water DOC, and freely dissolved aqueous phases in natural systems.
Organochlorine pesticides and polychlorinated biphenyls in household composts and earthworms (Eisenia foetida)
Authors: Wågman Nadja , Strandberg Bo , van Bavel Bert , Bergqvist Per-Anders , Öberg Lars , Rappe Christoffer 
Published: March 2010

AbstractThree indoor, household composts and the earthworms living in them were analyzed for their congener-specific content of polychlorinated biphenyls (PCBs) and organochlorine pesticides, including DDTs, chlordanes, dieldrin, and penta- and hexachlorobenzene. The concentrations of the chlordanes were 0.01 to 0.2 ng/g dry weight (dw) in compost and 0.03 to 0.06 ng/g wet weight (ww) in the worms. Of all the pesticides, the DDTs and chlorobenzenes were found in the highest concentrations. The levels of PCBs found in the composts were 32 to 440 ng sum PCB/g dw and 23 to 290 ng/g ww in the worms. These observations are in strong agreement with reported data from studies of outdoor composts. The PCB congener pattern was similar to that of commercial technical mixtures (dominated by tetrachlorinated PCBs) in contrast with data reported from outdoor composts.
Long-term bioconcentration kinetics of hydrophobic chemicals inSelenastrum capricornutumandMicrocystis aeruginosa
Authors: Koelmans Albert A , van der Woude Hannelore , Hattink Jasper , Niesten Dominique J M 
Published: March 2010

AbstractThe bioconcentration of two chlorobenzenes (CBs) and of seven polychlorobiphenyls (PCBs) to Selenastrum capricornutum and Microcystis aeruginosa was studied with accumulation experiments followed by gas purge elimination experiments. Henry's law constants at 10°C were needed to interpret the gas purge results and were measured in control experiments. For the M. aeruginosa culture, steady-state uptake was reached within days, whereas uptake by S. capricornutum took several weeks. The relationships between the log bioconcentration factors (BCF) and log octanol–water partition coefficients (Kow) were nonlinear, with relatively low values for the more hydrophobic PCBs. Rate constants for the elimination of CBs and PCBs from the algal cells were shown to be larger than 1 per day when calculated with a one-compartment model. With such large rate constants, it is unlikely that the curvature observed for these species is caused by slow kinetics or that algal growth affects BCF by dilution of CB or PCB concentrations. The log BCF–log Kow relationships could be described by a simple three-phase model that accounted for the binding of CBs and PCBs to dissolved organic carbon (DOC). Modeling bioconcentration of hydrophobic chemicals in phytoplankton should account for the binding to DOC.
Toxicity of copper-spiked sediments to Tubifex tubifex (oligochaeta, tubificidae): Comparison of the 28-day reproductive bioassay with an early-life-stage bioassay
Authors: Vecchi Martina , Reynoldson Trefor B , Pasteris Andrea , Bonomi Giuliano 
Published: March 2010

Abstract
Two sediment bioassay methods using Tubifex tubifex (Müller, 1774) as the test species were compared. The first was an adult reproduction test, the second an early-life-stage survival test. The duration of both bioassays is 28 d and the amount of work required was similar; they may be useful alternatives to each other in different circumstances (e.g., the early life stage bioassay could be carried out with smaller volumes of sediment). The two bioassays were performed simultaneously on copper-spiked sediments. Sediments from two freshwater and two terrestrial sites were used; five separate, nonsimultaneous experiments were performed, one for each sediment or soil and a further experiment with soil with a food supplement. In the adult bioassay, there were large differences in the production of cocoons, eggs, and young among the control treatments of the five experiments. There were also major differences in the NOEC (no-observed-effect concentration) and LOEC (lowest-observed-effect concentration) for copper between the tested substrates. The early life stage bioassay appears to be less sensitive to copper toxicity than the adult reproductive bioassay since NOECs and LOECs are higher for early survival than for the most sensitive endpoints of the adult bioassay in three experiments out of five.
Copper binding affinity of rainbow trout (Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis) gills: Implications for assessing bioavailable metal
Authors: MacRae Russell K , Smith Darren E , Swoboda-Colberg Norbert , Meyer Joeseph S , Bergman Harold L 
Published: March 2010

AbstractIn this study, we determined the conditional stability constant (log K′) of copper for the gills of rainbow trout (Oncorhynchus mykiss; RBT) and brook trout (Salvelinus fontinalis; BT). Using toxicity-based complexation bioassays, which measure the effect of competing organic ligands on copper toxicity, the RBT gill copper log K′ range was 6.4 to 7.2. Using a Scatchard analysis of gill Cu accumulation, the RBT log K′ was 7.50 and the BT log K′ was 7.25. The close agreement in RBT log K′ values between these two methods suggests that measurement of gill copper accumulation is an acceptable alternative for determining a toxicity-based gill copper binding affinity. Our results also suggest that there is either a single gill copper binding component or, more realistically, multiple components with similar binding properties that function collectively to define a single toxicologically relevant copper conditional stability constant. These results suggest analytical approaches to measuring bioavailable metal concentrations, such as geochemical modeling where biological ligands are included in speciation calculations, may adequately simulate complex biological ligands. A method to convert gill copper accumulation to a bioavailable water criterion is also discussed.
Lead exposure in passerines inhabiting lead-contaminated floodplains in the Coeur D'Alene River Basin, Idaho, USA
Authors: Johnson Gregory D , Audet Daniel J , Kern John W , LeCaptain Leonard J , Strickland M Dale , Hoffman David J , McDonald Lyman L 
Published: March 2010

AbstractBlood collected from song sparrows (Melospiza melodia) and American robins (Turdus migratorius) captured with mist nets in a lead-contaminated (assessment) area and nearby uncontaminated (reference) areas within the Coeur d'Alene Basin in northern Idaho was analyzed for δ-aminolevulinic acid dehydratase activity (ALAD) and hematocrit levels, and livers were analyzed for lead. Mean ALAD inhibition in the assessment area was 51% in song sparrows and 75% in American robins. The proportion of the sampled population with ALAD inhibition &gt;50% was calculated to be 43% for song sparrows and 83% for American robins. Assessment area hematocrit values for song sparrows (x = 39.9) and American robins (x = 39.5) were lower than in reference areas (x = 42.4 for song sparrows and 40.2 for American robins); however, differences were not statistically significant (p &gt; 0.05). Significantly higher levels of lead (wet weight) were found in livers from song sparrows captured on the assessment area (x = 1.93 ppm) than on reference areas (x = 0.10 ppm) (p = 0.0079). Study results indicate that 43% (95% confidence interval [CI] = 12.9-77.5%) of the song sparrows and 83% (95% CI = 41.8-99.2%) of the American robins inhabiting the floodplain along the Coeur d'Alene River in the assessment area are being exposed to lead at levels sufficient to inhibit ALAD by &gt; 50%. Variability in lead exposure indicators was attributed to high variability in environmental lead concentrations in the Coeur d'Alene River Basin.
Ecotoxicological assessment of solid wastes: A combined liquid- and solid-phase testing approach using a battery of bioassays and biomarkers
Authors: Ferrari Benoit , Radetski Claudemir Marcos , Veber Anne-Marie , Ferard Jean-Francois 
Published: March 2010

Abstract
Municipal solid waste incinerator bottom ash (MSWIBA) was used as a test matrix for comparing the responses of different variables (solid phase vs leachate media) through toxicity tests and resulting endpoints. Toxicity of leachate and solid-phase MSWIBA was evaluated with three terrestrial plants, namely oats (Avena sativa L.), Chinese cabbage (Brassica campestris L. cv. chinensis), and lettuce (Lactuca sativa L.). Assessment endpoints for these plant tests were biomass fresh weight, germination rate, and oxidant stress enzyme activities (superoxide dismutase, catalase, peroxidase, and glutathione reductase). Leachate MSWIBA toxicity was tested with bacteria (Vibrio fischeri), algae (Pseudokirchneriella subcapitata), and microcrustaceans (Daphnia magna and Ceriodaphnia dubia). A large range of toxicity responses was obtained with the various bioassays. With plant tests, the phytotoxicity of MSWIBA was revealed by the solid-phase approach, whereas no toxicity was observed with the MSWIBA leachate. The increase of oxidant stress enzyme activities was demonstrated to be a good indicator of solid or leachate phase toxicity.