bluuebunny/crossref_metadata_2025_split huggingface dataset:
Persistent organic pollutants in air and vegetation from the canadian rocky mountains
Authors: Davidson Deborah A. , Wilkinson Andrew C. , Kimpe Lynda E. , Blais Jules M. 
Published: March 2005

Abstract
The exchange of chlorinated organic pollutants between air and vegetation in cold, mountain environments was investigated through the extraction of coniferous vegetation and high-volume air samples collected from the Canadian Rocky Mountains during the summers of 1999 and 2000. Concentrations of several compounds in vegetation increased as temperatures decreased, whereas atmospheric concentrations were not related to temperature. Daily cycling of these compounds between air and vegetation as a result of diurnal temperature changes was not observed. Compared with concentrations in vegetation from the Canadian Rocky Mountains, plant samples from the western valley in British Columbia (Canada) showed higher pollutant levels. Chemical partitioning between vegetation and air was not correlated with temperature, indicating that air contamination is governed by long-range transport and not by local revolatilization events. Based on these observations, we show that both deposition at higher altitudes and long-range atmospheric transport influence chemical accumulation in vegetation from the Canadian Rocky Mountains.
European starling (Sturnus vulgaris): Avian model and monitor of polychlorinated biphenyl contamination at a Superfund site in Southern Illinois, USA
Authors: Arenal Christine A. , Halbrook Richard S. , Woodruff Maryjo 
Published: March 2005

Abstract
Accumulation and effects of polychlorinated biphenyls (PCBs) in avian species were evaluated at a Superfund site located at Crab Orchard National Wildlife Refuge (IL, USA). European starlings (Sturnus vulgaris) were monitored at nest boxes constructed at each of two study and two reference sites. During the breeding season, starling productivity and adult provisioning behavior were monitored. At 15 d after hatch, chicks and adults were collected for contaminant and biomarker analyses. Chicks and adults were necropsied, ethoxyresorufin-O-deethylase (EROD) activity was measured in liver tissue, and polychlorinated biphenyl (PCB; Aroclor 1254) and 34 chlorinated biphenyl (CB) congener concentrations were measured in carcasses. Polychlorinated biphenyl and CB concentrations also were measured in eggs that failed to hatch. Mean Aroclor 1254 and quantified CB concentrations were greater (p &lt; 0.001) in eggs that failed to hatch, 15-d-old chicks, and adults collected from PCB-contaminated sites (hereafter PCB sites) compared to those collected from reference sites. The EROD activity was greater (p = 0.005) in 15-d-old chicks, but not adults (p = 0.972), collected from PCB sites compared to those collected from reference sites. No differences were found among study and reference sites in number of eggs laid or percent of eggs hatched; however, reduced nest provisioning behavior and decreased chick survival were observed at PCB sites. Polychlorinated biphenyl concentrations measured in samples collected from the PCB sites are similar to concentrations previously associated with adverse effects in avian species. Other avian species utilizing these sites also may be exposed to PCBs with associated adverse effects. This study demonstrates that starling nestlings are good biological monitors of local contamination and continued monitoring may provide useful data for evaluating the effectiveness of proposed remediation.
Copper tolerance in fathead minnows: II. Maternal transfer
Authors: Peake Elizabeth B. , Locke Jessica C. , Tierney Laura L. , Kolok Alan S. 
Published: March 2005

Abstract
Female fathead minnows (Pimephales promelas) exposed to copper (Cu) maternally transfer Cu tolerance to their larval offspring. Larvae produced after female parents received a sublethal 5-d, 100 μg/L Cu exposure had significantly greater survivorship in potentially lethal Cu solutions than larvae produced before those females were exposed to Cu.
Assessment of bioavailability limitations during slurry biodegradation of petroleum hydrocarbons in aged soils
Authors: Huesemann Michael H. , Hausmann Tom S. , Fortman Tim J. 
Published: March 2005

Abstract
In an effort to determine whether bioavailability limitations are responsible for the slow or incomplete hydrocarbon biodegradation in aged soils, both the rate of desorption (rdes) and biodegradation (rbio) was measured for n-alkanes and polynuclear aromatic hydrocarbons (PAHs) at different times during the slurry biotreatment of six different soils. While all n-alkanes were biodegraded to various degrees depending on their respective carbon number and the soil organic matter content, none of them were desorbed to a significant extent, indicating that these saturated hydrocarbons do not need to be transferred from the soil particles into the aqueous phase in order to be metabolized by microorganisms. Most two- and three-ring PAHs biodegraded as fast as they were desorbed (rbio = rdes); that is, desorption rates controlled biodegradation rates. By contrast, the biodegradation kinetics of four-, five-, and six-ring PAHs was limited by microbial factors during the initial phase (rbio &lt; rdes) while becoming mass-transfer rate limited during the final phase of bioremediation treatment (rbio = rdes). Whenever PAH biodegradation stalled or did not occur at all (rbio = 0), it was never due to bioavailability limitations (rdes ≫ 0) but was more likely caused by microbial factors, such as the absence of specific PAH degraders or cometabolic substrates. Consequently, PAHs that are found to be microbially recalcitrant in aged soils may not be so because of limited bioavailability and thus could pose a greater risk to the environment than previously thought.
Mechanisms of cadmium toxicity in terrestrial pulmonates: Programmed cell death and metallothionein overload
Authors: Chabicovsky Monika , Klepal Waltraud , Dallinger Reinhard 
Published: March 2005

Abstract
A sublethal dose of cadmium (Cd2+) administered via the diet during short-term exposure over 10 d induced programmed cell death in the hepatopancreas of the terrestrial pulmonate snail Helix pomatia. Condensed cell residues were predominantly phagocytosed by calcium cells, suggesting a specific function of these epithelial cells in metal detoxification or in clearing the organ of cellular debris from cell death. The considerable cell loss recorded by histological analysis was accompanied by enhanced cell proliferation. Intoxication with Cd was further associated with the pronounced abundance of residual bodies, predominantly recorded in excretory cells, and with pathological changes in the endoplasmic reticulum. During long-term Cd exposure, mortality increased with increasing Cd concentrations in the diet, as demonstrated by feeding experiments in the laboratory. Lethal effects of Cd appeared to be correlated with Cd overloading of the Cd-specific metallothionein isoform (Cd-MT), isolated and characterized previously from the animal's hepatopancreas. Stoichiometric analysis shows that the capacity of Cd-MT to bind six molar equivalents of Cd corresponds to a tissue Cd concentration of approximately 4 μmol/g dry weight. At this tissue concentration, all high-affinity metal-binding sites of Cd-MT are occupied by Cd2+. Cadmium exposure beyond this level gives rise to progressive destabilization of Cd-MT cluster structure in vitro, resulting in increasing proportions of weakly bound, or even unbound, Cd2+ ions. Our results suggest that in vivo, the observed overburdening of Cd-MT with Cd2+ reduces the viability of affected animals.
Acute and chronic toxicity of nickel to a cladoceran (Ceriodaphnia dubia) and an amphipod (Hyalella azteca)
Authors: Keithly James , Brooker John A. , Deforest David K. , Wu Benjamin K. , Brix Kevin V. 
Published: March 2005

Abstract
This study evaluated acute and chronic nickel (Ni) toxicity to Ceriodaphnia dubia and Hyalella azteca with the objective of generating information for the development of a biotic ligand model for Ni. Testing with C. dubia was used to evaluate the effect of ambient hardness on Ni toxicity, whereas the larger H. azteca was used to derive lethal body burden information for Ni toxicity. As was expected, acute C. dubia median lethal concentrations (LC50s) for Ni increased with increasing water hardness. The 48-hLC50s were 81, 148, 261, and 400 μg/L at hardnesses of 50, 113, 161, and 253 mg/L (as CaCO3), respectively. Ceriodaphnia dubia was found to be significantly more sensitive in chronic exposures than other species tested (including other daphnids such as Daphnia magna); chronic toxicity was less dependent on hardness than was acute toxicity. Chronic 20% effective concentrations (EC20s) were estimated at &lt;3.8, 4.7, 4.0, and 6.9 μg/L at hardnesses of 50, 113, 161, and 253 mg/L, respectively. Testing with H. azteca resulted in a 96-h LC50 of 3,045 μg/L and a 14-d EC20 of 61 μg/L at a hardness of 98 mg/L (as CaCO3). Survival was more sensitive than was growth in the chronic study with H. azteca. The 20% lethal accumulation effect level based on measured Ni body burdens was 247 nmol/g wet weight.
Toxicity of endosulfan to Atalophlebia spp. (Ephemeroptera) in the laboratory, mesocosm, and field
Authors: Hose Grant C. , Hyne Ross V. , Lim Richard P. 
Published: March 2005

Abstract
A series of single-species toxicity tests was conducted in the laboratory and in outdoor stream mesocosms. The mayfly nymphs of Atalophlebia spp. (A. av2 and A. av6) were exposed to the organochlorine pesticide endosulfan for either 12- or 48-h periods, with mortality recorded after 96 h. For both exposure periods, the lethal concentration (LC50 and LC10) values were not significantly different between laboratory and mesocosm single-species tests, suggesting that the absence of natural environmental conditions and biological interactions in laboratory single-species tests did not influence the toxicity of technical endosulfan to Atalophlebia spp. Interpolation of toxicity test data indicates that peak endosulfan concentrations recorded in the rivers during storm events are likely to cause only minimal impact on Atalophlebia spp. populations. This suggests that changes in the abundance of populations observed in the field, if due to total endosulfan alone, are the result of chronic rather than acute exposure.
Gender and spatial patterns in metal concentrations in brown anoles (Anolis sagrei) in Southern Florida, USA
Authors: Burger Joanna , Campbell Kym Rouse , Campbell Todd S. 
Published: March 2005

Abstract
Comparatively little is known about heavy metal levels in reptiles, particularly for lizards. Yet lizards often are common predators that could serve as bioindicators of contamination on a small spatial scale. This study examined the differences in metal concentrations of adult brown anoles (Anolis sagrei) for arsenic, cadmium, chromium, lead, manganese, mercury, and selenium in six locations in southern Florida, USA, from Lake Okeechobee (Pahokee) south to Key West. We predicted that levels of contaminants would be higher in the industrialized ports (Port Everglades, Port of Miami) and at a landfill (in Key West) compared to a campground, tropical garden, and marine laboratory. Males were significantly larger than females, as expected. Although there were significant locational differences in metal concentrations, they did not fit a consistent pattern, either among sites or between reference and study sites. However, the lowest levels were generally found at Everglades Marina and Campground (except for selenium) and at Fairchild Tropical Garden (except for manganese). For females, size was significantly correlated with cadmium, lead, and mercury levels, while for males, there were significant correlations between length and arsenic, chromium, and manganese concentrations. Where there were gender differences in metal levels, females had significantly higher levels than males even though they were smaller. We attribute these gender differences to differences in diet due to microhabitat differences in foraging locations. Females spend more time feeding near the ground and males spend more time feeding on tree trunks and branches where they consume more flying insects. This is the first study that examines concentrations of metals in lizards in the United States, and suggests that nonnative lizards may be useful in toxicological studies.
A comparison of the fish bioconcentration factors for brominated flame retardants with their nonbrominated analogues
Authors: Hardy Marcia L. 
Published: March 2005

Abstract
Flame retardants (FR) play a significant role in reducing the flammability of many consumer products. On a volume basis, approximately 25% of the FRs in use today utilize bromine as the active flame-retarding moiety. Their applications are those requiring high FR performance or in resins needing an FR that is active during the gas phase. Laboratory fish bioconcentration factors (BCFs) for 11 brominated FRs (BFRs) or their components were compared with those for their nonbrominated analogues. Bioconcentration, defined here as a BCF of greater than 1,000, was not observed in those brominated molecules examined with molecular weights of 700 or greater. These included the decabromodiphenyl oxide and octabromodiphenyl oxide commercial products, ethane 1,2-bis(pentabromophenyl), ethylene bis-tetrabromophthalimide, and decabromobiphenyl. Tetrabromobisphenol A, with a molecular weight of less than 700, also did not bioconcentrate. This likely relates to the ease with which it is metabolized and eliminated. Within the BFR class of polybrominated diphenyl oxides/ethers, the BCFs for those congeners with molecular weights of between approximately 450 and 700 varied with the number and position of the bromine atoms. The BCF of hexabromocyclododecane appeared to be related to its cyclododecane substructure, not to its bromine content. Bioconcentration was not a characteristic feature of the BFRs examined here.
Microbial transformation of pyrethroid insecticides in aqueous and sediment phases
Authors: Lee Sangjin , Gan Jianying , Kim Jong-Sik , Kabashima John N. , Crowley David E. 
Published: March 2005

Abstract
Recent studies showed that synthetic pyrethroids(SPs)can move via surface runoff into aquatic systems. Fifty-six of SP-degrading bacteria strains were isolated from contaminated sediments, of which six were evaluated for their ability to transform bifenthrin and permethrin in the aqueous phase and bifenthrin in the sediment phase. In the aqueous phase, bifenthrin was rapidly degraded by strains of Stenotrophomonas acidaminiphila, and the half-life (t1/2) was reduced from &gt;700 h to 30 to 131 h. Permethrin isomers were degraded by Aeromonas sobria, Erwinia carotovora, and Yersinia frederiksenii. Similar to bifenthrin, the t1/2 of cis- and trans -permethrin was reduced by approximately 10-fold after bacteria inoculation. However, bifenthrin degradation by S. acidaminiphila was significantly inhibited in the presence of sediment, and the effect was likely caused by strong adsorption to the solid phase. Bifenthrin t1/2 was 343 to 466 h for a field sediment, and increased to 980 to 1200 h for a creek sediment. Bifenthrin degradation in the inoculated slurry treatments was not greatly enhanced when compared with the noninoculated system. Therefore, although SP-degrading bacteria may be widespread in aquatic systems, adsorption to sediment could render SPs unavailable to the degraders, thus prolonging their persistence.
Fipronil effects on estuarine copepod (Amphiascus tenuiremis) development, fertility, and reproduction: A rapid life-cycle assay in 96-well microplate format
Authors: Chandler G. Thomas , Cary Tawnya L. , Volz David C. , Walse Spencer S. , Ferry John L. , Klosterhaus Susan L. 
Published: March 2005

Abstract
Fipronil is a novel γ-aminobutyric acid receptor-specific phenylpyrazole insecticide commonly used near estuarine environments for rice production, turf-grass management, and residential insect control. In this study, we evaluated the acute, developmental, and reproductive toxicity of fipronil to the estuarine harpacticoid copepod Amphiascus tenuiremis. Fipronil was highly toxic to A. tenuiremis (adult 96-h median lethal concentration [LC50] = 6.8 μg/L) and was more toxic to male copepods (96-h LC50 = 3.5 μg/L) than to nongravid female copepods (96-h LC50 = 13.0 μg/L). By using a newly developed 96-well microplate-based life-cycle toxicity test, we successfully reared single individuals of A. tenuiremis to adulthood in 200-μl microwells and concurrently assessed developmental and reproductive effects (after paired virginal matings) of environmentally relevant aqueous fipronil concentrations (0.16, 0.22, and 0.42 μg/L measured). Throughout the entire life cycle, copepod survival in all treatments was &gt;90%. However, fipronil at 0.22 μg/L and higher significantly delayed male and female development from stage 1 copepodite to adult by approximately 2 d. More importantly, fipronil significantly halted female egg extrusion by 71% in the 0.22-μg/L fipronil treatment, and nearly eliminated reproduction (94% failure) in the 0.42-μg/L fipronil treatment. A three-generation Leslie matrix-based population growth model of fipronil reproductive and life-cycle impacts predicted a 62% decline in population size of A. tenuiremis relative to controls at only 0.16 μg/L.
Trivalent chromium alters gene expression in the mummichog (Fundulus heteroclitus)
Authors: Maples Nikki L. , Bain L Isa J. 
Published: March 2005

Abstract
Mummichogs (Fundulus heteroclitus) were used as a model fish species to study the effects of trivalent chromium exposure. To ascertain chromium's effects, we examined altered gene expression by differential display between fish exposed in the laboratory and fish collected from a chromium-impacted estuarine site. Twenty differentially expressed genes were found from either laboratory-exposed fish or in fish collected from the field site. Database sequence searches indicated that several of these genes are highly homologous to known sequences, including a fatty acid-binding protein (FABP), cytochrome P4502N2 (CYP2N2), and a precursor to the translation initiation factor eIF2B. Verification of the differentially expressed genes by real-time polymerase chain reaction (PCR) revealed that the fatty acid-binding protein was repressed to a 3.6-times greater extent (3.6-fold) in the field-site animals as compared to a reference site, eIF2B was repressed 2-fold, and an expressed sequence tag (EST) termed A31 was induced 2.6-fold. In the laboratory-exposed animals, A31 was also induced between 2- and 4-fold. However, in contrast to the field-site fish, FABP was upregulated in the chromium-exposed animals. We hope to be able to use A31 as a biomarker for ascertaining the impacts of chromium exposure on fish.
Recommendations for the assessment of TNT toxicity in sediment
Authors: Conder Jason M. , La Point Thomas W. , Steevens Jeffery A. , Lotufo Guilherme R. 
Published: March 2005

Abstract
Previous investigations of the ecotoxicity of TNT in spiked sediments noted the rapid degradation and disappearance of the toxicant, yet little is understood regarding the effects of this process on toxicity and subsequent derivation of toxicity reference values. We conducted environmental fate studies and 28-d sediment toxicity tests with benthic oligochaete worms (Tubifex tubifex) with sediments spiked at three different TNT concentrations (440, 1,409, and 4,403 nmol/g dry wt) aged for 1, 8, and 29 d. Because of rapid degradation of TNT, disappearance of degradation products, and partitioning to overlying water, only 25 to 40% of the added nitroaromatic mass balance was associated with sediment immediately after spiking. Lethal toxicity decreased with aging time and was best described by measured sediment nitroaromatic concentrations (sum of TNT and degradation products) at the beginning of exposure, with a median lethal concentration of nitroaromatic compounds of 184 nmol/g dry weight. To accurately describe the ephemeral exposure doses of TNT and its degradation products during toxicity tests with spiked sediments, we suggest that sediments should be aged at least 8 to 14 d after spiking, exposure should be based on measured sediment concentrations or chemical measures of availability, exchange of overlying water should be avoided or minimized, and short-term toxicity tests should be considered.
Biomonitoring of contaminants in birds from two trophic levels in the North Pacific
Authors: Rocque Deborah A. , Winker Kevin 
Published: March 2005

Abstract
The presence and accumulation of persistent contaminants at high latitudes from long-range transport is an important environmental issue. Atmospheric transport has been identified as the source of pollutants in several arctic ecosystems and has the potential to severely impact high-latitude populations. Elevated levels of contaminants in Aleutian Island avifauna have been documented, but the great distance from potential industrial sources and the region's complex military history have confounded identification of contaminant origins. We sampled bird species across the natural longitudinal transect of the Aleutian Archipelago to test three contaminant source hypotheses. We detected patterns in some polychlorinated biphenyl congeners and mercury that indicate abandoned military installations as likely local point sources. Carbon isotopes were distinct among island groups, enabling us to rule out transfer through migratory prey species as a contaminant source. The long-range transport hypothesis was supported by significant west-to-east declines in contaminant concentrations for most detected organochlorines and some trace metals. Although relatively low at present, concentrations may increase in Aleutian fauna as Asian industrialization increases and emitted contaminants are atmospherically transported into the region, necessitating continued monitoring in this unique ecosystem.
Sorption of steroid estrogens to soils and sediments
Authors: Yu Zhiqiang , Xiao Baohua , Huang Weilin , Peng Ping'An 
Published: March 2005

Abstract
Steroid estrogens at sub-micrograms per liter levels are frequently detected in surface water, and increasingly cause public concern of their potential impacts on ecosystems and human health. Assessing the environmental fate and risks of steroid estrogens requires accurate characterization of various physicochemical and biological processes involving these chemicals in aquatic systems. This paper reports sorption of three estrogens, 17β-estradiol (estradiol), estrone, and 17α-ethinyl estradiol (EE2), by seven soil and sediment samples at both equilibrium and rate-limiting conditions. The results indicated that attainment of sorption equilibrium needs about 2 d when aqueous estrogen concentrations (Cts) are 25 to 50% of their solubility limits (SWs), but equilibrium requires 10 to 14 d when the Ct is 20 times lower than the SW. The measured sorption isotherms are all nonlinear, with the Freundlich model parameter n ranging from 0.475 to 0.893. The observed isotherm nonlinearity correlates to a gradual increase of single-point organic carbon-normalized sorption distribution coefficient (capacity) (KOC) as the equilibrium estrogen concentration (Ce) decreases. At Ce = 0.5SW, all three estrogens have log KOC values of 3.14 to 3.49, whereas at Ce = 0.02SW, the log KOC values for estrone, EE2, and estradiol are within ranges of 3.40 to 3.81, 3.45 to 3.85, and 3.71 to 4.12, respectively. This study suggests that, when at sub-micrograms per liter levels, these estrogenic chemicals may exhibit even slower rates and greater capacities of sorption by soils and sediments.