bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vapor pressures, aqueous solubilities, and Henry's law constants of some brominated flame retardants
Authors: Tittlemier Sheryl A. , Halldorson Thor , Stern Gary A. , Tomy Gregg T. 
Published: March 2010

Abstract
The subcooled liquid vapor pressures (P°L,25s) and aqueous solubilities (Sw,25s) were determined and Henry's law constants (H25s) were estimated for a number of brominated flame retardants (BFRs) at 25°C. The established methods of the gas chromatography-retention time and generator column techniques were used to experimentally determine P 0L,25 and Sw,25 for hexabromobenzene and a series of brominated diphenyl ether (BDE) congeners. The H25 was estimated as the ratio of P 0L,25 to the subcooled liquid aqueous solubility. Values of P 0L,25 obtained ranged from 0.000000282 Pa (BDE-190) to 0.259 Pa (BDE-3); Sw,25 ranged from 0.00000087 g/L (BDE-153 and BDE-154) to 0.00013 g/L (BDE-15); and H25 ranged from 0.0074 Pa m3/mol (BDE-183) to 21 Pa m3/mol (BDE-15). An increase in the bromine content of polybrominated diphenyl ether congeners resulted in significant decreases of P 0L,25, Sw,25, and H25. A simple four-compartment equilibrium distribution model suggested that the majority of BFRs being released into the environment would reside in soil and sediment and have localized distributions. The model also suggested that lower brominated congeners tend to be somewhat more mobile. Degradative debromination reactions that yield these congeners would mobilize them environmentally, and ultimately affect the fate and distribution of BFRs.
Environmental cadmium induces histopathological changes in kidneys of roe deer
Authors: Beiglböck Christoph , Steineck Theodora , Tataruch Frieda , Ruf Thomas 
Published: March 2010

AbstractKidney samples of 224 roe deer (113 males, 111 females) aged three months to approximately nine years were collected in eastern Austria. Cadmium contents were examined and histological examinations were performed considering 11 different pathomorphological parameters. Cadmium burden was relatively high (range: 0.010-22.076 ppm) and increased with age. Females aged one to two years had higher contents than males of the same age. The culling site had no influence on cadmium load. The relation between the occurrence of histopathological changes and age, sex, origin, and cadmium concentration in 208 roe deer was tested. The frequency of vacuolic degeneration, pycnotic nuclei, caryolysis, and necrosis was related to increased cadmium levels. Increasing age correlated with lymphohistiocytic infiltration, interstitial fibrosis, and swelling of glomeruli. Pigment deposits and thickening of Bowman's capsule could be related to both cadmium and age. Furthermore, roe deer from an industrialized region showed alterations more frequently than animals from rural areas. We found no relation between morphological changes and sex. Though it remains to be established whether environmental cadmium exposure is the sole cause for the histopathological alterations observed, the results of this study indicate that chronic cadmium poisoning may be an important cofactor in the pathogenic mechanisms of renal damage in roe deer and that cadmium intoxication may be more widespread among wildlife than previously known.
Uptake and loss of chlorpyrifos and atrazine byJuncus effususL. in a mesocosm study with a mixture of pesticides
Authors: Lytle Julia S. , Lytle Thomas F. 
Published: March 2010

AbstractAquatic organisms in agricultural regions typically are exposed to mixtures of agrochemicals, and effects are not adequately predicted from results of single pesticide exposure studies. Thus, a mesocosm study was designed to examine the fate and effects of varying mixtures of three pesticides (chlorpyrifos, atrazine, and monosodium methanearsonate) and mercury-contaminated sediment to the common freshwater macrophyte Juncus effusus L. Exposure doses of pesticides added to mesocosms represented those that might be encountered in a typical runoff or direct spray application. This study reports the uptake and loss of chlorpyrifos and atrazine in the leaves of J. effusus after a single and a repeated dose of the chemical mixture over 94 d. The measured chlorpyrifos levels in leaves were highest on day 1, but levels in both leaves and water dropped rapidly and were at background levels by day 32. Atrazine remained near nominal concentrations in the water through day 16 and reached maximum accumulation in the leaves on day 16. The chemical mixture affected uptake of chlorpyrifos more strongly than atrazine as measured by differences in uptake variability. After the second dose, J. effusus showed a similar uptake pattern for both compounds, although somewhat faster, to that observed after the first dose, with no diminished capacity for uptake of either compound. The greater volatility of chlorpyrifos, the higher solubility of atrazine, and the more efficient transport of atrazine to the root zone are characteristics that are consistent with the differences observed in their uptake and loss behavior.
Biochemical effects of chlorpyrifos on two developmental stages ofXenopus laevis
Authors: Richards Sean M. , Kendall Ron J. 
Published: March 2010

AbstractThe effects of a 96-h static exposure to chlorpyrifos were examined in two developmental stages of larval Xenopus laevis (premetamorph and metamorph). Measures of effect included mortality, deformity, cholinesterase (ChE) activity, and DNA and protein concentration. All parameters indicated that metamorphs were more sensitive than were premetamorphs. For larvae exposed as premetamorphs, the median lethal concentration and median effective concentration were 14.6 mg/L and 1.71 mg/L; for those exposed as metamorphs, values were 0.56 mg/L and 0.24 mg/L, respectively. Cholinesterase activity was the most sensitive biochemical parameter. Exposure to chlorpyrifos at 0.01 mg/L caused significant decreases in the ChE activity of metamorphs; 0.1 mg/L significantly decreased premetamorph ChE activity. Metamorph DNA was significantly decreased at 0.1 mg/L; premetamorph DNA was not reduced until exposure to 1.0 mg/L. Whole-body protein was the least sensitive biochemical measure of effect. Premetamorphs did not experience a reduction in protein concentrations. Metamorph protein concentration was significantly decreased at 1.0 mg/L. Based on current surface water data, the most sensitive effect would not have a high probability (≤4.2%) of occurring in the environment.
Cadmium-induced production of a metallothioneinlike protein inTubifex tubifex(Oligochaeta) andChironomus riparius(Diptera): Correlation with reproduction and growth
Authors: Gillis Patricia L. , Diener Lara C , Reynoldson Trefor B. , Dixon D. George 
Published: March 2010

AbstractLaboratory-cultured Chironomus riparius and Tubifex tubifex were exposed to sediments artificially enriched with a range of cadmium (Cd) concentrations. Both species accumulated Cd in a concentration-dependent manner. The concentration of a metallothioneinlike protein (MTLP), as measured by a mercury saturation assay, increased with increasing Cd exposure. After reaching a threshold of Cd exposure, the whole-body endpoints of reproductive output in T. tubifex and growth in C. riparius declined significantly. The threshold effect concentrations for T. tubifex and C. riparius were 2.68 and 0.134 μmol Cd/g dry sediment, respectively. Metallothioneinlike protein and Cd tissue concentrations were more sensitive indicators of exposure than the whole-body endpoints. For T. tubifex, the concentrations of MTLP and tissue Cd were significantly elevated above control levels after exposure to the 0.67 μmol Cd/g dry sediment treatment. In C. riparius, MTLP concentration and tissue Cd concentration were both significantly elevated above control levels after exposure to the 3.8 × 10−3 μmol Cd/g dry sediment treatment. Analysis of these data suggests that MTLP and tissue Cd concentrations are sensitive subcellular endpoints, which can be used to predict exposure to and the effects of metals at the individual or population level.
Transplanted zebra mussels (Dreissena polymorpha) as active biomonitors in an effluent-dominated river
Authors: Smolders Roel , Bervoets Lieven , Blust Ronny 
Published: March 2010

Abstract
For over 20 years, mussels have been recommended as one of the most suitable biomonitoring organisms for aquatic ecosystems. Though the common mussel (Mytilus edulis) is frequently used for biomonitoring estuarine and marine ecosystems, no freshwater species is promoted for similar monitoring networks. Recently, however, the zebra mussel (Dreissena polymorpha) has been proposed as a suitable monitoring organism in freshwater ecosystems. The aim of this study was to explore the usefulness of transplanted zebra mussels as active biomonitors in an effluent-dominated stream. Results showed that for these purposes, an exposure period of at least a few weeks is required to detect any significant changes in condition status or scope for growth. Wet-tissue-weight:dry-tissue-weight ratio was the most sensitive measure to quantify effects of field exposure on physiological fitness. In case of scope for growth (SfG), energy intake was the factor determining the overall energy budget of the mussels. Based on the dilution rates of the two different effluents present, effluent 2 had the most important effect on the condition status of the exposed organisms. Overall, we conclude that the use of transplanted mussels is a sensitive and easily applicable active biomonitor that can be used to assess water quality, pollution, and subsequent recovery through self-purification in field situations.
Fish (Fundulus heteroclitus) populations with different exposure histories differ in tolerance of creosote-contaminated sediments
Authors: Ownby David R. , Newman Michael C. , Mulvey Margaret , Vogelbein Wolfgang K. , Unger Michael A. , Arzayus L. Felipe 
Published: March 2010

Abstract
Prior studies suggest that field-collected fish (Fundulus heteroclitus) from a creosote-contaminated Superfund site (Atlantic Wood Industries site, Elizabeth River, VA, USA) have enhanced tolerance to local, contaminated sediments. This study was designed to test whether other populations in the Elizabeth River at less contaminated sites also show similar tolerance and whether this tolerance is heritable. To test this, F. heteroclitus populations were sampled from four sites within the Elizabeth River with varying sediment polycyclic aromatic hydrocarbon (PAH) concentrations (3.9–264 ng PAH/g dry wt·103) and one reference site in a nearby, uncontaminated estuary (York River, VA, USA; 0.27 ng PAH/g dry wt·103). Embryo assays were performed to quantify population differences in teratogenic effects during contaminated sediment exposure. Atlantic Wood sediment was mixed with reference sediment to achieve a range of sediment concentrations. Minimal differences were observed in teratogenic effects among fish taken from sites within the Elizabeth River; however, embryos of fish collected from a nearby, uncontaminated York River site and exposed to contaminated sediments had a significantly higher proportion of embryos with cardiac abnormalities than those from the Elizabeth River sites. Embryos from wild-caught and laboratory-reared Elizabeth River F. heteroclitus were simultaneously exposed to contaminated sediments, and no significant tolerance differences were found between embryos from fish taken directly from the field and those reared for a generation in the lab. Differences between fish populations from the two estuaries were larger than differences within the Elizabeth River, and these differences in tolerance were heritable.
Acute and chronic toxicity of zinc to the mottled sculpin Cottus bairdi
Authors: Woodling John , Brinkman Stephen , Albeke Shannon 
Published: March 2010

Abstract
The acute and chronic toxicity of zinc to wild mottled sculpin (Cottus bairdi) was measured with 13-d and 30-d flow-through toxicity tests, respectively. Exposure water hardness was 48.6 mg/L as CaCO3 and 46.3 mg/L as CaCO3 in the acute and chronic tests, respectively; pH was slightly above neutral; and temperature near 12°C. The median lethal concentration (LC50) after 96 h was 156 μg Zn/L, but decreased with exposure duration to a median incipient lethal level (ILL50) of 38 μg Zn/L after 9 d, the lowest zinc LC50 reported for any fish species. The 30-d chronic no-effect and lowest-effect concentrations were 16 μg Zn/L (no mortality) and 27 μg Zn/L (32% mortality), respectively. The ILL50 was 32 μg Zn/L. No sublethal growth differences were observed during the chronic test. Analysis of the results from these tests suggested that mottled sculpin may experience acute and chronic toxicity at zinc concentrations lower than any other fish species tested to date. Protection of aquatic communities in stream reaches contaminated by metals seem to require determination of zinc toxicity to lotic species other than trout and other species amenable to aquaculture.
Relative sensitivity of three terrestrial invertebrate tests to polycyclic aromatic compounds
Authors: Sverdrup Line E. , Krogh Paul Henning , Nielsen Torben , Stenersen Jørgen 
Published: March 2010

AbstractIn a project investigating the ecotoxicity of polycyclic aromatic compounds (PACs), we have previously reported on the sublethal toxicity of eight PACs to springtails (Folsomia fimetaria) and enchytraeids (Enchytraeus crypticus). The model substances included four polycyclic aromatic hydrocarbons (PAHs) and four N-S-O-heterocyclics. Here, new data are presented on the effects of PACs on the survival and growth of the earthworm Eisenia veneta, showing that, in general, earthworm growth was reduced at PAC concentrations above 25 mg/kg soil dry weight. The E. veneta tests were performed using the same soil type and very similar test conditions as for the F. fimetaria and E. crypticus tests, thus providing a good opportunity to compare the sensitivity of these three organisms. Species sensitivity was examined using the 50% reduction in survival (LC50 values) and no-observable-effect concentrations (NOEC values) for growth or reproduction as endpoints. The difference between the least and most sensitive species was generally much larger for LC50 values as compared to the NOEC values, suggesting a higher degree of uncertainty when extrapolating from one species to another for the LC50 data. For the NOEC data, relatively small differences in sensitivity was observed, but as a rather consistent pattern, F. fimetaria was the most sensitive and E. crypticus the least sensitive species. However, one substance (acridine) showed specific toxicity toward E. veneta, which was more sensitive than the two other species by more than one order of magnitude.
Evaluation of androstenedione as an androgenic component of river water downstream of a pulp and paper mill effluent
Authors: Durhan Elizabeth J. , Lambright Christy , Wilson Vickie , Butterworth Brian C. , Kuehl Douglas W , Orlando Edward F. , Guillette Louis J. , Gray L. Earl , Ankley Gerald T. 
Published: March 2010

Abstract
This study evaluates a recent report indicating that androstenedione (4-androsten-3, 17-dione) contributes to the andro-genicity of water downstream of a pulp and paper mill discharge on the Fenholloway River (FL, USA). Extraction and concentration of Fenholloway water with C18 solid-phase extraction columns followed by reverse-phase high-pressure liquid chromatography resulted in clearly defined fractions with in vitro androgenic activity in CV-1 cells that had been transiently cotransfected with human androgen receptor and reporter gene constructs. However, we were unable to detect androstenedione in the active fractions by gas chromatography/mass spectrometry. Mass spectrometry analyses of deionized and Fenholloway River water samples that had been spiked with androstenedione, then extracted and fractionated, revealed that the androgen was found only in inactive fractions. We conclude that, although androstenedione was present at easily detectable concentrations in the river water (&gt;100 ng/L), this compound is not associated with androgenic activity of water from the site.
Application of the luciferase recombinant cell culture bioassay system for the analysis of polycyclic aromatic hydrocarbons
Authors: Ziccardi Michael H. , Gardner Ian A. , Denison Michael S. 
Published: March 2010

AbstractAn aryl hydrocarbon (Ah) receptor-based luciferase cell culture bioassay developed to detect 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and other halogenated aromatics was modified and optimized to detect and quantitate polycyclic aromatics (PAHs). Twenty-four PAHs were analyzed, and subsequent EC50 and EC20 concentrations (based on the median and 20% TCDD maximal response, respectively) and appropriate induction equivalency factors (calculated by comparison to the response obtained with TCDD) were determined from dose-response experiments. Six compounds were shown to be active in the system, with benzo[k]fluoranthene &gt; benz[a,h]anthracene ≈ indeno[1,2,3-cd]pyrene &gt; benzo[a]pyrene &gt; benzo[b]fluoranthene &gt; chrysene. A complex mixture of 16 PAHs was also analyzed using this system, and overall induction equivalency (or I-EQ) of the mixture was shown to be very similar to that predicted from the sum of the activity estimated for each individual PAH. Overall, our results strongly support the use of this system for the detection and relative quantitation of Ah receptor-active PAHs.
Products of aqueous chlorination of 4-nonylphenol and their estrogenic activity
Authors: Hu Jian-Ying , Xie Guo-Hong , Aizawa Takako 
Published: March 2010

Abstract
Seven reaction products (2-chloro-4-nonylphenol [NP], 2,6-dichloro-4-NP, trichlorophenol, 4-propyl-2′-hydroxyphenol, 4-isobutyl-2′-hydroxyphenol, 4-isoamyl-2′-hydroxyphenol, and 4-isopentyl-2′-hydroxyphenol) were identified by gas chromatography/mass spectrometry (GC/MS) in order to assess the estrogenic activity originated from 4-nonylphenol (4-NP) in drinking water. The estrogenic activities of the aqueous chlorinated 4-NP solution at 10, 60, and 120 min chlorination time were assessed by a yeast two-hybrid system based on the ligand-dependent interaction of two proteins, a human estrogen receptor (ER), and a coactivator. It was found that all three solutions inhibited transcriptional activation induction by 4-NP. Further experiments showed that these solutions also inhibited β-galactosidase induction by 17β-estradiol. For the solution at 10 min, the inhibition was found to be due to its toxicity, with an inhibition concentration (IC50) of about 10-fold of concentration of chlorinated 4-NP solution, suggesting the existence of some products with higher yeast toxicity than that of the parent 4-NP. Similar inhibition trends were also found in the dose response of the two solutions at 60 and 120 min, with an IC50 of 10-fold concentration. In these cases, the effects were considered to result from their antagonist action because the two solutions show lower yeast toxicity of which IC50 is 45-fold concentration. This suggests that some products in the chlorinated 4-NP solution elicit the antiestrogenic activities.
Silver concentrations in Colorado, USA, watersheds using improved methodology
Authors: Wen Liang-Saw , Santschi Peter H. , Gill Gary A. , Tang Degui 
Published: March 2010

Abstract
River water samples were collected at five sites in the state of Colorado, USA, to assess the impact of municipal and industrial discharges on Ag concentrations and speciation in surface waters. Samples were collected and analyzed for total (unfiltered collections), filtered (0.1 and 0.4 μm), particulate (≥0.45 μm), and colloidal Ag (3 kDa-0.1 μm) using ultraclean protocols. A series of laboratory experiments were conducted to assess bias from sample storage, digestion, and preconcentration protocols. In general, upstream unfiltered and particulate Ag concentrations fell within a fairly narrow range, 3.1 to 21 ng/L and 0.2 to 1.7 μg/g, respectively. Downstream unfiltered and particulate Ag concentrations showed a more broad range, 2.8 to 1,110 ng/L and 0.5 to 104 μLg/g, respectively, and reflected attenuated impacts of Ag-laden discharge effluents. However, Ag concentrations in the 0.1-μm filter-passing fraction 0.8 to 1.2 km downstream from major treatment plant effluents were all below the chronic silver criteria. On average, more than 60% of the 0.1-μm filter-passing Ag was associated with colloidal macromolecular organic matter. Silver concentrations in colloids (μg/g) were, on average, the same as those in suspended particulate matter. The percentage abundance of colloidal Ag was similar to that of dissolved organic carbon, suggesting that strong Ag binding ligands exist in both the colloidal and the particle size fractions, as these macromolecular ligands likely play a major role in Ag speciation.
Aerobic degradation of ethyl-tert-butyl ether by a microbial consortium: Selection and evaluation of biodegradation ability
Authors: Kharoune Mourad , Kharoune Lynda , Lebault Jean-Michael , Pauss André 
Published: March 2010

Abstract
A microbial consortium that degrades ethyl-tert-butyl ether (ETBE) as the sole source of carbon and energy under aerobic conditions was selected from a gasoline-polluted soil. This consortium consists of a variety of microorganisms with a predominance of filamentous morphology. Degradation of ETBE was found to be solely related to bacterial activity. After prolonged cultivation followed by successive transfers, the consortium's degradation ability was improved and reached a specific degradation rate of 95 mg/gprotein/h (about 146 mg/gdry wt/h). This exceeds the previously reported rates in the literature for ETBE-degrading microorganisms as pure or mixed cultures. Furthermore, a stoichiometric balance of chemical oxygen demand (COD) removal and oxygen uptake with ETBE removal provides indirect evidence of complete degradation. The consortium's activity was not inhibited by high ETBE concentrations (≤1,600 mg/L), and large inoculum sizes (≥120 mgprotein/L) were desirable for a faster and complete degradation of ETBE. The enriched consortium was also able to completely degrade methyl-tert-butyl ether (MTBE), tert-amyl methyl ether (TAME), and tert-butyl alcohol (TBA), both alone and in mixture with ETBE, without any measurable release of major degradation intermediates. In each case, MTBE and TAME exhibited the most significant resistance to degradation while TBA was rapidly degraded.
Effect of pH on cadmium toxicity, speciation, and accumulation during naphthalene biodegradation
Authors: Sandrin Todd R. , Maier Raina M. 
Published: March 2010

Abstract
Lowering pH of a microbiological medium from 7 to 4 decreased cadmium toxicity during naphthalene biodegradation by a Burkholderia sp. Cadmium speciation and cadmium accumulation in the system were studied to explain this effect. Cadmium speciation was determined by direct measurement and by geochemical modeling. Previous studies have implicated the monovalent hydroxylated cadmium (CdOH+) species in the effect of pH on cadmium toxicity. Modeling analysis predicted CdOH+ formation only at very low concentrations (≤0.0128 μM), while the measured concentration of divalent ionic cadmium (Cd2+) was at least three orders of magnitude greater, suggesting that Cd2+ is the more significant metal form. With respect to cadmium accumulation, cells contained in media adjusted to pH 4 accumulated only 2.76 ± 0.76 mg Cd/g cells, whereas cells in media adjusted to pH 7 accumulated 8.52 ± 0.71 mg Cd/g cells. These data suggest that cadmium toxicity is correlated with increased cadmium accumulation rather than the formation of CdOH+ as pH is increased. At low pH, the decrease in cadmium accumulation may be caused by increased competition between hydrogen and cadmium ions for binding sites on the cell surface or by an increase in metal efflux pump activity due to an increase in the proton gradient that drives the efflux pump.