bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative evaluation of hepatic cytochrome P4501A transcript, protein, and catalytic activity in the striped sea bream (Lithognathus mormyrus)
Authors: Tom Moshe , Shmul Merav , Shefer Edna , Chen Nir , Slor Hanoch , Rinkevich Baruch , Herut Barak 
Published: November 2004

Abstract
Hepatic cytochrome P4501A (CYP1A) expression was partially characterized in the striped sea bream (Lithognathus mormyrus) from the Mediterranean coast of Israel as part of the process of establishing the CYP1A gene as an environmental biomarker. Reverse transcription-competitive polymerase chain reaction, competitive enzyme-linked immunosorbent assay, and ethoxyresorufin O-deethylase (EROD) assay were used for evaluating transcript, protein, and catalytic activity levels, respectively, in absolute units. Highest elucidated transcript, protein, and catalytic activity levels were 0.264 ± SD 0.084 fmol/μg total RNA, 0.88 ± 0.52 pmol/μg total protein, and 1.11 ± 0.52 pmol resorufin/min/μg total protein, respectively, and the lower levels were 0.009 ± 0.007 fmol/μg total RNA, 0.17 ± 0.08 pmol/μg total protein, and 0.11 ± 0.06 pmol resorufin/min/μg total protein, respectively, demonstrating substantial induction potential. All alternate pairs of seven examined field samples, revealing a transcript-level ratio higher than 1.7, also demonstrated a significant difference between their transcript levels, indicating a potential to detect relatively small biomarker changes (1.7-fold) caused by environmental effects. Simultaneous triple measurements of transcript, protein, and catalytic activity were carried out in individuals from two field samples and during a 318-d decay experiment. Fish from the field samples revealed significant alternate bivariate correlation between transcript, protein, and enzymatic activity. Conflicting results were found when analyzing the decay experiment, in which both protein and catalytic activity levels decreased significantly to basal levels, in contrast to no significant change in transcript levels throughout the experiment. No significant difference was observed between males and females regarding the levels of CYP1A transcript, protein, and EROD.
Bioavailability of the organophosphorous insecticide chlorpyrifos to the suspension-feeding bivalve, Mercenaria mercenaria, following exposure to dissolved and particulate matter
Authors: Bejarano Adriana C. , Widenfalk Anneli , Decho Alan W. , Chandler G. Thomas 
Published: November 2004

Abstract
Under estuarine conditions, hydrophobic, hydrophobic pesticides physical/chemical partitioning into dissolved and particulate fractions of sediments. Our experimental study using 14C-chlorpyrifos (14C-CHPY) showed that sorptive associations of this common insecticide with particulate (&gt;0.2 μm) and dissolved fractions (&lt;0.2 μm) of sediments strongly influenced uptake, tissue absorption, and elimination in the estuarine bivalve Mercenaria mercenaria. Bivalves were fed algae mixed with particulate and dissolved fractions of 14C-CHPY-contaminated estuarine sediment particles, components of estuarine sediments (silica, humic acids), and a naturally occurring food source (phytoplankton) to quantify relative uptake, tissue absorption efficiencies, and elimination of 14C-CHPY. Measurements of 14C-CHPY tissue absorption efficiencies (AE%) indicated that particle source qualities influenced much of the insecticide bioavailability. Mean tissue AE% of 14C-CHPY associated with different particulate fractions ranged from 23 to 31%, while uptake from the dissolved/colloidal forms resulted in low (7-17%) AE%. Our data indicated that 14C-CHPY is more likely to bioaccumulate through ingestion of contaminated particulate material than through filtration/ingestion of dissolved/colloidal material. The high selectivity and digestibility of algae particles by M. mercenaria, a potentially ingested food source, may play an important role in the bioavailability of chlorpyrifos in this animal.
The use of toxicity bioassays to monitor the recovery of oiled wetland sediments
Authors: Mueller Danica C. , Bonner James S. , McDonald Susanne J. , Autenrieth Robin L. , Donnelly Kirby C. , Lee Kenneth , Doe Kenneth , Anderson Jack 
Published: November 2004

Abstract
Six toxicity assays were compared to determine their efficacy in assessing toxicity dynamics during a wetland bioremediation study. The toxicity bioassays used were the Microtox® 100% elutriate test, Microtox Solid Phase Test (SPT), amphipod assay, P450 reporter gene system, Toxi-ChromoPad™ test and a Salmonella/microsome assay. Oiled sediments were analyzed for toxicity in the petroleum biostimulation experiment conducted along the San Jacinto River, near Houston (TX, USA). The bioassays were evaluated for their ability to measure acute toxicity, chronic toxicity, and the mutagenic potential of amended oiled plots as compared to oiled and unoiled control plots. Amendments were diammonium phosphate alone or in combination with potassium nitrate, which served as an alternate electron acceptor. With exception of the Toxi-ChromoPad and Salmonella tests, the bioassays exhibited a significant increase in toxicity after oil application. Microtox bioassays detected significant sediment toxicity up to 29 d after oil and amendment application. The Microtox solid phase test results correlated strongly with gas chromatographymass spectrometry analyses of total target saturate and aromatic hydrocarbons. The amphipod assay detected initial toxicity with a decline to day 70, followed by a significant increase in toxicity on day 140 in plots receiving nutrient amendments, which may be in response to excessive nutrient application. Low levels of enzyme induction were observed with the P450 reporter gene system assay in all oiled sediments throughout the study, suggesting low but persistent levels of polycyclic aromatic hydrocarbons. Of the six tests, the two Microtox tests and the amphipod test showed the most potential in evaluating petroleum toxicity in wetland sediments.
Lead and stable lead isotope ratios in soil, earthworms, and bones of American woodcock (Scolopax minor) from eastern Canada
Authors: Scheuhammer Anton M. , Bond Della E. , Burgess Neil M. , Rodrigue Jean 
Published: November 2004

Abstract
A study to discriminate among different possible sources of elevated Pb exposure for American woodcock (Scolopax minor) in eastern Canada is described. Undamaged wing bones excised from young-of-the-year woodcock collected from several locations in southern Ontario, southern Quebec, New Brunswick, and Nova Scotia, Canada, along with soil and earthworm (Aporrectodea tuberculata and Lumbricus rubellus) samples from the same sites, were analyzed for total Pb, and stable Pb isotopes. Ignoring six soil samples with high (&gt;60 μg/g) Pb concentration from the vicinity of Montreal (QC, Canada), the mean soil-Pb concentration for all sites combined was 19 μg/g (dry wt; n = 64), with a mean 206Pb:207Pb ratio of 1.19, values typical for uncontaminated rural soils in eastern North America. In earthworms, Pb concentrations ranged from 2.4 to 865 (μg/g [dry wt], mean = 24 μg/g). Concentrations of Pb in worms and soils were positively correlated (r = 0.71; p &lt; 0.01), and 206Pb:207Pb ratios for worms and soils were also positively correlated (r = 0.54; p &lt; 0.05). However, most young-of-the-year woodcock with high bone-Pb accumulation (&gt;20 μg/g) had 206Pb:207Pb ratios substantially different from worms and soils sampled from the same areas, even though woodcock feed extensively on soil invertebrates, especially earthworms. The range of 206Pb:207Pb ratios in wing bones of woodcock with elevated Pb exposure was not consistent with exposure to environmental Pb from past gasoline combustion nor Precambrian mining wastes but was consistent with ingestion of spent Pb shotgun pellets.
Response of the zooplankton community and environmental fate of perfluorooctane sulfonic acid in aquatic microcosms
Authors: Boudreau Timothy M. , Wilson Christian J. , Cheong Woo Jay , Sibley Paul K. , Mabury Scott A. , Muir Derek C. G. , Solomon Keith R. 
Published: November 2004

Abstract
Little is known regarding perfluorooctane sulfonic acid (PFOS) toxicity to freshwater organisms. This field evaluation aims to assess the toxicological risk associated with exposure to PFOS across levels of biological organization. The analysis of variance study was conducted in replicate (n = 3) 12,000 L outdoor microcosms. Multivariate techniques were used to assess the response of zooplankton community structure and dynamics, as well as a floating macrophyte, Lemna gibba. The zooplankton community was significantly affected (p &lt; 0.05) by the treatment regime given by the Monte Carlo permutations for all sampling times. A community-level no-observable-effect concentration ([NOEC]community) of 3.0 mg/L was determined for the 35-day study, however, longer term studies are recommended. The most sensitive taxonomic groups, Cladocera and Copepoda, were virtually eliminated in 30 mg/L treatments after 7 d. The 42-d 50% inhibition concentration (IC50) for L. gibba frond number was 19.1 mg/L and the NOEC was 0.2 mg/L. Furthermore, we investigated the persistence of PFOS over 285 d in microcosms under natural conditions. Perfluorooctane sulfonic acid concentration showed no drastic reduction in any treatment microcosm over the entire study period, confirming that this compound undergoes little degradation in aquatic systems. Presently, there appears to be little hazard to these freshwater organisms at reported environmental concentrations.
Microcosm tributyltin bioaccumulation and multibiomarker assessment in the blue mussel Mytilus edulis
Authors: Devier Marie-Hélène , Augagneur Sylvie , Budzinski Hélène , Mora Pascal , Narbonne Jean-Franclois , Garrigues Philippe 
Published: November 2004

Abstract
Blue mussels, Mytilus edulis, were exposed to two different concentrations of tributyltin (TBT) in seawater, 1,000 ng Sn/L (C1 experiment) and 10 ng Sn/L (C2 experiment), for 4 d, in order to evaluate the bioaccumulation of TBT by mussels Mytilus edulis in microcosms and to test the ability of a multimarkers analysis to determine the effects of TBT on the biochemical parameters in mussels. Tissue burdens of Mytilus edulis were 204 ± 7 and 2,120 ± 4 ng Sn/g TBT after the 4-d tests for the C2 and C1 experiments, respectively. Analyses of dissected organs and/or tissues demonstrated that TBT accumulated to the greatest extent in gills in the C1 experiment and in the digestive gland in the C2 experiment. Bioconcentration factors (BCFs) were 12,100 ± 300 and 2,000 ± 10 for mussels exposed in the C2 and C1 experiments, respectively. The four biomarkers used in this work were acetylcholinesterase (AChE), glutathione S-transferase (GST), catalase (CAT) activities, and thiobarbituric acid-reactive substances (TBARS) contents. No significant changes were observed in the measured enzyme activities or in TBARS concentration after the 4-d TBT exposure.
Intraclonal variability in Daphnia acetylcholinesterase activity: The implications for its applicability as a biomarker
Authors: Printes Liane Biehl , Callaghan Amanda 
Published: November 2004

Abstract
The relationship between individual growth and acetylcholinesterase (AChE) activity was evaluated for Daphnia magna. Analysis on the influence of two different culture media on baseline AChE activity was performed with Daphnia similis. The results indicated an inverse relationship between D. magna body length and AChE activity. An increase in total protein, which was not proportional to an increase in the rate of the substrate hydrolysis (Δ absorbance/min), seems to be the reason for this inverse size versus AChE activity relationship. Therefore, toxicants such as phenobarbital, which affect protein and size but not AChE activity directly, have an overall affect on AChE activity. In contrast, the AChE inhibitor parathion altered AChE activity but not protein. Culture medium also had a significant affect on AChE activity in D. similis. Changes in total protein seem to be the main reason for the variations in baseline AChE activity in Daphnia observed in the different evaluations performed in this work. Therefore, AChE activity in Daphnia must be interpreted carefully, and variations related to changes in total protein must be taken into account when applying this enzyme as a biomarker in biological monitoring.
Extraction of spiked metals from contaminated coastal sediments: A comparison of different methods
Authors: Fan Wenhong , Wang Wen-Xiong 
Published: November 2004

Abstract
Various extraction methods have been developed to assess metal bioavailability from sediments. In this study, we compared the extraction of Cd, Cr, and Zn from contaminated sediments using different extractants (normal seawater, acidic seawater of pH = 5, seawater with 1% sodium dodecyl sulfate [SDS], and gut digestive fluids collected in vitro from deposit-feeding peanut worm Sipunculus nudus) coupled with concurrent metal speciation measurements. The influences of sediment aging on metal extraction were also examined using radiotracer-spiked techniques. Sediments aging up to 100 d did not significantly affect the partitioning of spiked Cd and Cr in different geochemical phases, but the spiked Zn was partitioned more into the reducible fraction and less into the carbonate phase with increasing sediment aging. There was a major difference in the partitioning into different geochemical phases between the spiked metals and the native metals within the 100-d sediment aging. The difference between the spiked and native Cd and Zn extraction using gut juices was somewhat smaller than the strong geochemical contrast. Metals bound with the anoxic sediments were hardly extracted by different extractants. There was a significant relationship between the extraction of spiked Cd and its distribution in the exchangeable phase (positive correlation) or in the reducible phase (negative correlation). For Cr and Zn, extraction was not correlated with their partitioning in any of the geochemical phases. Further, extraction of all three metals by digestive gut fluids was not correlated with the concentrations of simultaneously extractable metals (SEM), nor with the difference between SEM and acid volatile sulfide (AVS). Our study suggests that there were large differences in extraction among metals using different extractants and only Cd extraction was significantly related to its geochemical speciation in sediments.
Association mechanisms of europium(III) and curium(III) with Chlorella vulgaris
Authors: Ozaki Takuo , Kimura Takaumi , Ohnuki Toshihiko , Yoshida Zenko , Francis Arokiasamy J. 
Published: November 2004

Abstract
The association of Europium(III) (Eu[III]) and Curium(III) (Cm[III]) with Chlorella vulgaris and with cellulose was studied by a batch method and time-resolved laser-induced fluorescence spectroscopy (TRLFS). The kinetics study performed by the batch method showed that maximum adsorption of Eu(III) and Cm(III) on C. vulgaris was attained within 3 min of contact; afterward, the percentage adsorption decreased with time due to chelation of the ions with exudates released from C. vulgaris with a strong affinity for Eu(III) and Cm(III). The TRLFS revealed that the short-term adsorption of Eu(III) on C. vulgaris was attributable to its coordination with cellulose on the algal cell wall. However, Eu(III) coordinated with the functional groups of cellulose very weakly despite the large distribution coefficients observed. These results indicate that the reactions, both at the cell's surfaces through adsorption and in solution phases through chelation with the exudates, are important in estimating the behavior of Eu(III) and Cm(III) in aqueous environments.
The relationship of bioaccumulative chemicals in water and sediment to residues in fish: A visualization approach
Authors: Burkhard Lawrence P. , Cook Philip M. , Mount David R. 
Published: November 2004

Abstract
A visualization approach is developed and presented for depicting and interpreting bioaccumulation relationships and data (i.e., bioaccumulation factors [BAFs], biota-sediment accumulation factors [BSAFs], and chemical residues in fish) using water–sediment chemical concentration XY plots. The approach is based on five basic parameters that affect bioaccumulation of nonionic organic chemicals: The distribution of chemical between sediment and water, the hydrophobicity of the compound (expressed as the n-octanol/water partition coefficient, Kow), the relationship of food chains to water and sediment, the length of the food chains, and the degree to which the chemical is metabolized. The visualization approach using water–sediment XY plots captures and visually presents the existing bioaccumulation knowledge in a form that is readily understandable from chemical, biological, and ecological aspects and, therefore, useful in the assessment, communication, and management of risk for persistent bioaccumulative toxicants.
Field contamination of the starfish Asterias rubens by metals. Part 1: Short- and long-term accumulation along a pollution gradient
Authors: Coteur Geoffroy , Pernet Philippe , Gillan David , Joly Guillemette , Maage Amund , Dubois Philippe 
Published: November 2004

Abstract
The accumulation of Cd, Pb, Zn, and Cu in the starfish Asterias rubens was studied in a Norwegian fjord characterized by a gradient of metal pollution in the sediments, ranging from very high metal concentrations at its head to much lower levels at its opening. The concentrations of metals in starfish from natural populations along the gradient (long-term accumulation) and in starfish that were transferred up the gradient (short-term accumulation) were compared. At long-term, Cd and Pb accumulations by starfish living at normal salinity (30‰) were related to the level of contamination of of the environment while Cu and, to a lesser extent, Zn accumulations appeared strictly controlled. At short-term, Pb was accumulated steadily, Cd and Zn were accumulated transiently in the pyloric caeca (fast compartment), and Cu was not accumulated at all. Depuration experiments (transfer down the gradient) showed that Cd and Pb were efficiently eliminated from the pyloric caeca but not from the body wall (slow compartment). It is concluded that Pb is chronically accumulated, without apparent control, Cd is subjected to a regulating mechanism in the pyloric caeca which is overwhelmed over the long-term; Zn is tightly controlled in the pyloric caeca and Cu in both pyloric caeca and body wall. A distinct color variety of starfish is restricted to the low salinity (22-26‰) superficial water layer. This variety showed a different pattern of metal accumulation over the long-term. This pattern is attributed to the particular hydrological conditions prevailing in this upper layer.
Factors influencing variability and potential uptake routes of heavy metals in black kites exposed to emissions from a solid-waste incinerator
Authors: Blanco Guillermo , Frías Oscar , Jiménez Begoña , Gómez Gema 
Published: November 2004

Abstract
Exposure to heavy metals from emissions of the solid-waste incinerator (SWI) of Madrid (Spain) was assessed by determining the relationships between the distance from black kite (Milvus migrans) nests to the SWI and metal concentrations in nestling blood and failed eggs. Lead levels increased as the distance to the SWI decreased, while no significant relationship was found for the remaining elements. Analysis of frequency distributions showed that Pb was normally distributed, suggesting a generalized exposure to this contaminant. Variability in metal levels within and between nests indicated a differential nest exposure to contaminant metals with sibling chicks showing similar metal levels. Correlations between essential and contaminant metals suggested detoxifying mechanisms mediated by essential metals. The contribution of metal residues in blood coming from deposition in eggs was minimal compared with residues coming from posthatch exposure. Exposure to particulate volatile Pb in the form of dust from fly ash emitted to the air by the SWI is suggested to be the main route of uptake via inhalation, while both dietary and respiratory routes may contribute to Cd uptake. The increasing human population living close to the SWI may be increasingly at risk from exposure to air-borne contaminants depending on the emission standards from the SWI.
Photoactivated toxicity in amphipods collected from polycyclic aromatic hydrocarbon–contaminated sites
Authors: Diamond Stephen A. , Milroy Nicholas J. , Mattson Vincent R. , Heinis Larry J. , Mount David R. 
Published: November 2004

Abstract
The risk of photoactivated PAH toxicity in contaminated aquatic systems has not been well characterized. To document risk, amphipods (Gammarus spp.) were collected from two polycyclic aromatic hydrocarbon (PAH)-contaminated sites in the lower St. Louis River and Duluth Harbor, USA (Hog Island and USX) as well as a reference site (Chipmunk Cove) and were exposed in two separate, replicate tests to controlled intensities of solar radiation for 3 d. Contaminated site organisms died significantly faster compared to control site organisms. In all tests, mortality was strongly related to ultraviolet-A (UV-A; 320–400 nm) dose. Ultraviolet-B (280–320 nm) radiation did not increase mortality. To compare susceptibility among populations, regressions of arcsine-transformed, proportionate mortality versus UV dose were completed for each, and the slopes were statistically compared. Response slopes for the two contaminated site populations were both significantly greater than the reference site population (p = 0.0001 for test 1; p = 0.0002 for test 2). These results indicate that organisms residing in PAH-contaminated environments can accumulate PAH concentrations sufficient to be at risk for photoactivated toxicity. Although amphipods are not typically at risk of PAH-photoactivated toxicity because they are largely protected from exposure to sunlight, they are representative surrogates for species that may be similarly protected at some life stages (and thus able to accumulate significant PAH tissue concentrations) but not at others.
Effects of surfactants on the dechlorination of chlorinated ethenes
Authors: McGuire Travis , Hughes Joseph B. 
Published: November 2004

Abstract
The influence of surfactants on a perchloroethene (PCE) dechlorinating mixed culture was investigated in laboratory experiments. Surfactants (Steol CS-330, Aerosol MA 80-I, alpha olefin sulfonate 14 to 16, Neodol 25-7, Tween 80, alkyl polyglycoside, C16TAB [trimethylammonium bromide], and sodium dodecyl sulfate) were evaluated for their effects on the rate and extent of PCE reductive dechlorination and their potential biodegradation by the mixed culture. Limited, if any, surfactant biodegradation was observed for the surfactants tested, and all surfactants impaired dechlorination in either the rate of PCE dechlorination or the terminal dechlorination products observed. Based on initial testing, a nonionic surfactant, Tween 80, and an anionic surfactant, Steol CS-330, were selected for additional investigation. Dechlorination of PCE to dichloroethene (DCE), vinyl chloride (VC), and ethene (ETH) occurred in all Tween 80–amended microcosms, with a depressed rate of ETH production as the only adverse effect. Steol CS-330, however, inhibited dechlorination beyond DCE at all surfactant concentrations exceeding 25 mg/L. Attempts to acclimate a culture to Steol CS-330 were unsuccessful. Inhibition of VC and ETH production was reversible on dilution of the surfactant to a concentration of 10 mg/L or less, indicating that surfactant interactions with the enzyme system responsible for reductive dechlorination of DCE may be the cause of inhibition.