bluuebunny/crossref_metadata_2025_split huggingface dataset:
Temporal and geographic trends in mercury concentrations in muscle tissue in five species of hudson river, USA, fish
Authors: Levinton Jeffrey S , Ochron Sharon T. P 
Published: July 2008

Abstract
We analyzed a New York (USA) state database of mercury concentrations in muscle tissue for five species of fish (striped bass, yellow perch, largemouth bass, smallmouth bass, and carp) over a range of locations in the Hudson River (USA) between 1970 and 2004. We used regression models to discern temporal and geographic change in the fish while controlling for a positive correlation between mercury concentration and body mass. Mercury concentrations significantly increased in fish from New York Harbor waters to the mid-Hudson River. Striped bass and yellow perch showed a shallower increase in mercury concentration with river mile than did carp, largemouth bass, and smallmouth bass. Mercury concentrations declined over the 34-year period. These results imply that a geographically restricted source of mercury may be spread throughout the watershed by toxin-laden dispersing species. The increase of mercury toward the north may relate to a point source in the mid-Hudson River, or it may indicate mercury released from the Adirondack watershed. The decline of mercury over three decades corresponds to a reduction of various inputs in the region. The temporal and geographic pattern of mercury in sediments corresponds to the geographic trend of mercury in fish.
DNA microarrays detect effects of soil contamination onArabidopsis thalianagene expression
Authors: Magrini Kimberly D , Basu Amit , Spotila James R , Avery Harold W , Bergman Lawrence W , Hammond Rachel , Anandan Shivanthi 
Published: July 2008

AbstractSoil contamination, such as heavy metals and benzene compounds, is a widespread problem on military installations. It is important to be able to determine the effects of soil contamination before any adverse effects appear in organisms in surrounding areas. We examined gene expression in Arabidopsis thaliana grown in soil from three sites at the Radford Army Ammunition Plant in Radford, Virginia, USA, using DNA microarrays. We analyzed soil, germination, and growth rate to compare with the microarray data. Soil contamination affected both external phenotype and gene expression. Plants grown in soil with high levels of contaminants were chloritic and were smaller than control plants grown in potting soil. Plants grown in soil with the highest copper concentration had the lowest growth rates and had genes up-regulated across several functional groups. Plants grown in soils with elevated lead had many genes down-regulated that were related to photosystem II, metabolism, cellular transport, and protein synthesis. Genes consistently up-regulated across most microarrays were genes related to photosystem I, genes related to water deprivation and oxidative stress response, heat shock proteins, and toxin catabolism genes such as glutathiones. DNA microarrays, in concert with a model genetic organism such as A. thaliana, were an effective assessment tool to determine the presence of toxic substances in soil at a site used for the production of military explosives.
Determination of physicochemical properties of tetrabromobisphenol A
Authors: Kuramochi Hidetoshi , Kawamoto Katsuya , Miyazaki Kohei , Nagahama Kunio , Maeda Kouji , Li Xian-Wei , Shibata Etsuro , Nakamura Takashi , Sakai Shin-Ichi 
Published: July 2008

Abstract
Aqueous solubility (Sw), 1-octanol/water partition coefficient (KOW), and vapor pressure of the nonionic form of 2,2′,6,6′-tetrabromo-4,4′-isopropylidenediphenol (tetrabromobisphenol A or TBBP-A) were measured. From this, enthalpies of solution and vaporization were estimated. Furthermore, enthalpy of fusion and melting point were measured to estimate subcooled liquid vapor pressure, the infinite dilution activity coefficient, and Henry's law constant. Since TBBP-A is expected to exit in both ionic and nonionic forms at near neutral pH, pH effects on physicochemical properties were also examined. Because of the ionization of TBBP-A, Sw increased by five orders of magnitude, while KOW decreased by eight orders of magnitude. Furthermore, an analytical model based on mass balance and dissociation of TBBP-A was applied to represent the pH dependence.
How to deal with lipophilic and volatile organic substances in microtiter plate assays
Authors: Schreiber René , Altenburger Rolf , Paschke Albrecht , Küster Eberhard 
Published: July 2008

Abstract
Microtiter plate-based assays are a promising technique for toxicity assessment of substances. Chemicals with physicochemical properties such as high volatility and/or high lipophilicity, however, can be lost from the exposure solution during an experiment, so that exposure concentrations are not consistent. The aim of the present study was to determine and reduce the proportion of the reference compounds phenanthrene and phenanthridine lost during exposure in the zebra fish (Danio rerio) embryo test regime. It could be shown that under the standard exposure regime (48 h), the concentration of phenanthrene decreased strongly, by more than 99%, whereas that of phenanthridine decreased by 17% during a 48-h experiment. After modifications to the microtiter plate exposure regime, the phenanthrene concentration showed a decrease of only 40%, while the phenanthridine concentration remained unchanged. The major processes of substance loss could be assigned to accumulations of these substances into the glue of commercially available adhesive foils and the polystyrene walls of the microtiter plates. Furthermore, by investigating the sorption capacity of different plastics, it was found that the phenanthrene concentration decreased less when using a plexiglass specimen (28%) compared with the same-sized polystyrene specimen (94%). Moreover, it was found, for a constant exposure regime, that concentration profiles of different phenanthrene concentrations in the microtiter plate assay during an experiment were similar. A mathematical method is proposed to predict concentration profiles in an exposure solution by scaling a determined profile.
Chemical and biological analysis of endocrine-disrupting hormones and estrogenic activity in an advanced sewage treatment plant
Authors: Muller Mathieu , Rabenoelina Fanja , Balaguer Patrick , Patureau Dominique , Lemenach Karin , Budzinski Hélène , Barceló Damia , López de Alda Miren , Kuster Marina , Delgenès Jean-Philippe , Hernandez-Raquet Guillermina 
Published: July 2008

Abstract
The steroid hormones estrone (E1), 17β-estradiol (E2), estriol (E3), 17α-ethinylestradiol (EE2), and their conjugated forms were surveyed throughout an advanced sewage treatment plant (STP). The estrogen concentrations in water and sludge samples, collected in October 2004 and April 2005, were determined by gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry. Simultaneously, the estrogenic activity was quantified using estrogen-responsive reporter cell lines (MELN) to investigate the behavior of overall estrogenic compounds. The estrogen concentrations in the inlet ranged from 200 to 500 ng/L, with the contribution of conjugated forms being higher than 50%. The major estrogens in influent were E1 and E3. The estrogenic activity was between 25 and 130 ng/L of E2 equivalents (EEQs). Estrogen concentrations and estrogenicity measured in the inlet and in primary treated sewage were similar, showing a weak impact of primary treatment on hormone removal. In contrast, both estrogen concentration and estrogenicity decreased during biological treatment, with high removal efficiencies (&gt;90%). Estrone, E2, and EE2 persisted in the treated water below 10 ng/L, whereas the estrogenicity was lower than 5 ng/L of EEQs. Estrogen mass flux in the effluent and sludge represented less than 2 and 4%, respectively, of the inlet. Consequently, the fraction of estrogens sorbed into the sludge was very small, and biodegradation was the main vehicle for estrogen elimination. This dual approach, comparing chemical and biological analysis, allowed us to confirm that most of the estrogenic activity occurring in this STP, which receives mainly domestic sewage, resulted from sex hormones.
Influence of soil properties on copper toxicity for two soil invertebrates
Authors: Criel Peggy , Lock Koen , Van Eeckhout Hilde , Oorts Koen , Smolders Erik , Janssen Colin R 
Published: July 2008

AbstractAlthough a large body of evidence indicates that metal toxicity to soil organisms is affected by physicochemical soil properties, use of this knowledge in ecological risk assessments is limited because of the lack of a model applicable to a wide range of soils. To study the effect of soil characteristics on the toxicity of copper to terrestrial invertebrates, chronic toxicity tests with Eisenia fetida and Folsomia candida were performed in 19 European field soils. These soils were carefully selected to cover the range of toxicity-influencing parameters encountered in the European Union. Toxicity values varied greatly among soils, with 28-d median effect concentrations ranging from 72.0 to 781 mg Cu/kg dry weight for E. fetida and from 45.4 to 2,270 mg Cu/kg dry weight for F. candida. For both species, variation in copper toxicity values was best explained by differences in the actual cation-exchange capacity (CEC) at soil pH. Using the obtained regression algorithms, the observed toxicity could, in most cases, be predicted within a factor of two for E. fetida and within a factor of three for F. candida. The developed models were validated in three additional European field soils, a standard artificial soil and a standard field soil. The presented regression equations, based on the actual CEC, offer an easy-to-apply method for taking the influence of soil properties on metal toxicity into account.
Development and validation of a congener-specific photodegradation model for polybrominated diphenyl ethers
Authors: Zeng Xia , Simonich Staci L. Massey , Robrock Kristin R , Korytár Peter , Alvarez-Cohen Lisa , Barofsky Douglas F 
Published: July 2008

Abstract
With the phaseout of the manufacture of some polybrominated diphenyl ether (PBDE) formulations, namely penta-brominated diphenyl ether (BDE) and octa-BDE, and the continued use of the deca-BDE formulation, it is important to be able to predict the photodegradation of the more highly brominated congeners. A model was developed and validated to predict the products and their relative concentrations from the photodegradation of PBDEs. The enthalpies of formation of the 209 PBDE congeners were calculated, and the relative reaction rate constants were obtained. The predicted reaction rate constants for PBDEs show linear correlation with previous experimental results. Because of their large volume use, their presence in the environment, and/or importance in the photodegradation of the deca-BDE formulation, BDE-209, BDE-184, BDE-100, and BDE-99 were chosen for further ultraviolet photodegradation experiments in isooctane. The photodegradation model successfully predicted the products of the photochemical reactions of PBDEs in experimental studies. A gas chromatography retention time model for PBDEs was developed using a multiple linear regression analysis and, together with the photodegradation model and additional PBDE standards, provided a way to identify unknown products from PBDE photodegradation experiments. Based on the results of the photodegradation experiments, as well as the model predictions, it appears that the photodegradation of PBDEs is a first-order reaction and, further, that the rate-determining step is the stepwise loss of bromine. Our results suggest that, based on photodegradation, over time, BDE-99 will remain the most abundant penta-BDE, while BDE-49 and BDE-66 will increase greatly and will be comparable in abundance to BDE-47.
Utilization of protein expression profiles as indicators of environmental impairment of smallmouth bass (Micropterus dolomieu) from the Shenandoah River, Virginia, USA
Authors: Ripley Jennifer , Iwanowicz Luke , Blazer Vicki , Foran Christy 
Published: July 2008

Abstract
The Shenandoah River (VA, USA), the largest tributary of the Potomac River (MD, USA) and an important source of drinking water, has been the site of extensive fish kills since 2004. Previous investigations indicate environmental stressors may be adversely modulating the immune system of smallmouth bass (Micropterus dolomieu) and other species. Anterior kidney (AK) tissue, the major site of blood cell production in fish, was collected from smallmouth bass at three sites along the Shenandoah River. The tissue was divided for immune function and proteomics analyses. Bactericidal activity and respiratory burst were significantly different between North Fork and mainstem Shenandoah River smallmouth bass, whereas South Fork AK tissue did not significantly differ in either of these measures compared with the other sites. Cytotoxic cell activity was highest among South Fork and lowest among North Fork AK leukocytes. The composite two-dimension gels of the North Fork and mainstem smallmouth bass AK tissues contained 584 and 591 spots, respectively. South Fork smallmouth bass AK expressed only 335 proteins. Nineteen of 50 proteins analyzed by matrix-assisted laser desorption ionization-time of flight were successfully identified. Three of the four identified proteins with increased expression in South Fork AK tissue were involved in metabolism. Seven proteins exclusive to mainstem and North Fork smallmouth bass AK and expressed at comparable abundances serve immune and stress response functions. The proteomics data indicate these fish differ in metabolic capacity of AK tissue and in the ability to produce functional leukocytes. The variable responses of the immune function assays further indicate disruption to the immune system. Our results allow us to hypothesize underlying physiological changes that may relate to fish kills and suggest relevant contaminants known to produce similar physiological disruption.
Ecotoxicological environmental risk limits for total petroleum hydrocarbons on the basis of internal lipid concentrations
Authors: Verbruggen Eric M. J , Beek Margriet , Pijnenburg Janny , Traas Theo P 
Published: July 2008

AbstractA method is described for deriving ecotoxicological environmental risk limits (ERLs) for total petroleum hydrocarbons (TPH). Toxicity data for two oil types (light and heavy) to benthic organisms and corresponding estimated internal lipid concentrations, calculated by equilibrium partitioning, are used as a measure of toxicity by narcosis. It is assumed that uptake by organisms takes place from the aqueous phase, and for partitioning, both oil droplets or coating and organic carbon of sediment are taken into account. To distinguish between the different fractions of TPH, the method used is based on a fraction analysis approach in which aliphatic and aromatic compounds are regarded separately and both are further divided into different fractions. A toxic unit approach is applied to these fractions to take additivity into account. Lethality of the lighter oil type (internal concentration 28–204 mmol/Llipid) was in good agreement with data on internal concentrations retrieved from the literature. For the heavier oil type the observed toxicity was slightly higher and can probably be attributed to physical soiling of the organisms by oil or oxygen depletion due to biodegradation of the oil. For deriving ERLs, chronic endpoints are considered. The most sensitive chronic endpoints appear to be similar for both types of oil. The distribution of estimated total internal concentrations for chronic endpoints (1.38–149 mmol/Llipid) is used as a basis for the ERLs. The resulting ERLs for the mixture of TPH are comparable with ERLs for single compounds.
Development of a new assay for evaluation of l-3,4-dihydroxyphenylalanine cytotoxicity in catalase-mutant Escherichia coli
Authors: Wang Da-Hong , Horita Masako , Tsutsui Ken , Sano Kuniaki , Sauriasari Rani , Masuoka Noriyoshi , Takemura Yoko , Takigawa Tomoko , Takaki Jiro , Ogino Keiki 
Published: July 2008

Abstract
The present study aimed to assess whether a newly constructed, catalase-deficient Escherichia coli strain that express mammalian catalase gene could be used to identify oxidative stress-generating chemicals. We tested L-3,4-dihydroxyphenylalanine (L-DOPA), a well-known agent that induces reactive oxygen species. We found that L-DOPA exposure reduced the survival of catalase-mutant E. coli in a dose-dependent manner, especially in the strains with lower catalase activities, implying the usefulness of these strains in assessment of oxidative chemicals.
Water-column concentrations and partitioning of polybrominated diphenyl ethers in the New York/New Jersey Harbor, USA
Authors: Zarnadze Archil , Rodenburg Lisa A 
Published: July 2008

Abstract
Despite the emerging concern regarding polybrominated diphenyl ethers (BDEs), very few measurements of BDE concentrations in ambient water have been published. In the present study, BDEs were measured in water samples from the New York/New Jersey Harbor (USA). Samples were taken in Raritan Bay west of Sandy Hook during four intensive sampling campaigns in 2000 and 2001. Congeners 17, 47, 99, 100, 153, 154, 183, and 209 were detected. Total BDE (σBDE) concentrations (average ± standard deviation) were 175 ± 75 ng/g in the particle phase and 110 ± 72 pg/L in the apparent dissolved phase. The deca-congener, BDE 209, constituted 85 and 9% of σBDEs in the particle and apparent dissolved phases, respectively. The σBDE levels are significantly higher than those measured in Lake Ontario, USA, and in The Netherlands, but they are similar to concentrations measured in Lake Michigan and San Francisco Bay (both USA). Calculated values of the organic carbon-water partition coefficient (KOC) were strongly correlated with literature values of the octanol-water partition coefficient (KOW). The data suggest that sorption of BDEs to colloids is important in this system, although quantifying the extent of colloid sorption is difficult.
Toxicodynamic assumptions in ecotoxicological hazard models
Authors: Ashauer Roman , Brown Colin D 
Published: July 2008

AbstractExisting toxicokinetic and toxicodynamic models and dynamic formulations of popular ecotoxicological concepts (e.g., the critical body residue concept) are examined. Their underlying assumptions about speed of recovery and thresholds are clarified, and a rigorous mathematical treatment shows that they can all be placed within a unifying framework. Such analysis aids in the selection of appropriate ecotoxicological models.
Toxicity and metal speciation in acid mine drainage treated by passive bioreactors
Authors: Neculita Carmen-Mihaela , Vigneault Bernard , Zagury Gérald J 
Published: July 2008

Abstract
Sulfate-reducing passive bioreactors treat acid mine drainage (AMD) by increasing its pH and alkalinity and by removing metals as metal sulfide precipitates. In addition to discharge limits based on physicochemical parameters, however, treated effluent is required to be nontoxic. Acute and sublethal toxicity was assessed for effluent from 3.5-L column bioreactors filled with mixtures of natural organic carbon sources and operated at different hydraulic retention times (HRTs) for the treatment of a highly contaminated AMD. Effluent was first tested for acute (Daphnia magna and Oncorhynchus mykiss) and sublethal (Pseudokirchneriella subcapitata, Ceriodaphnia dubia, and Lemna minor) toxicity. Acute toxicity was observed for D. magna, and a toxicity identification evaluation (TIE) procedure was then performed to identify potential toxicants. Finally, metal speciation in the effluent was determined using ultrafiltration and geochemical modeling for the interpretation of the toxicity results. The 10-d HRT effluent was nonacutely lethal for O. mykiss but acutely lethal for D. magna. The toxicity to D. magna, however, was removed by 2 h of aeration, and the TIE procedure suggested iron as a cause of toxicity. Sublethal toxicity of the 10-d HRT effluent was observed for all test species, but it was reduced compared to the raw AMD and to a 7.3-d HRT effluent. Data regarding metal speciation indicated instability of both effluents during aeration and were consistent with the toxicity being caused by iron. Column bioreactors in operation for more than nine months efficiently improved the physicochemical quality of highly contaminated AMD at different HRTs. The present study, however, indicated that design of passive treatment should include sufficient HRT and posttreatment aeration to meet acute toxicity requirements.
Changes in morphology of the ground beetle Pterostichus oblongopunctatus F. (coleoptera; carabidae) from vicinities of a zinc and lead smelter
Authors: Lagisz Malgorzata 
Published: July 2008

Abstract
The present study investigated the response of the ground beetle Pterostichus oblongopunctatus F. (Coleoptera, Carabidae) to heavy metal pollution by assessing morphological traits (elytra length and wing length). Elytra length (a measure of body size) decreased with increasing pollution levels, whereas wing length (an indicator of flight dispersal ability) showed little change. The decrease in body size suggests negative effects of pollutants on the development and, subsequently, fitness of this species.
Effects of malathion on embryonic development and latent susceptibility to trematode parasites in ranid tadpoles
Authors: Budischak Sarah A , Belden Lisa K , Hopkins William A 
Published: July 2008

Abstract
We investigated the effects of embryonic exposure to the widely used organophosphate malathion (15–600 μg/L) on the early development and latent susceptibility of pickerel frog (Rana palustris) tadpoles to the trematode parasite Echinostoma trivolvis. The latent effects of contaminant exposure are rarely examined but could have important implications for individual survival and population viability. Malathion decreased hatching success by 6.5% and viability rates by 17% at 600 μg/L, which is a lower concentration than previously documented for anuran embryos. Incidence of malformations increased from 0.5% in controls to 11.2% in the 600-μg/L malathion treatment. The primary malformations documented in the two highest pesticide concentrations were ventralization and axial shortening. After seven weeks of development in water with no malathion, tadpoles previously exposed as embryos for only 96 h to 60 and 600 μg/L malathion suffered increased parasite encystment rates when compared to controls. Our research identifies embryonic development as a sensitive window for establishing latent susceptibility to infection in later developmental stages.