bluuebunny/crossref_metadata_2025_split huggingface dataset:
Toxicity of conventional, elemental chlorine-free, and totally chlorine-free kraft-pulp bleaching effluents assessed by shortterm lethal and sublethal bioassays
Authors: Tarkpea Maria , Eklund Britta , Linde Margareta , Bengtsson Bengt-Erik 
Published: March 2010

Abstract
The toxicity of nine effluents from Swedish kraft-pulp mills using conventional, elemental chlorine-free (ECF) and totally chlorine-free (TCF) bleaching processes was studied. Effluents represented six different processes: conventional-softwood 30% ClO2; ECF-softwood; TCF-hardwood, for which all the samples were taken before and after secondary treatment; conventional-softwood 8% ClO2; TCF-softwood O3/H2O2; and TCF-softwood H2O2. Comparison of effluents, which had not undergone secondary treatment, suggested that those from mills using conventional bleached pulp were the most toxic, with toxic emission factors (TEF) ≈ 1,000 according to the Microtox® test (AZUR Environmental, Carlsbad, CA, USA). In the acute Nitocra spinipes test, the conventional-softwood 8% ClO2 and the ECF-softwood effluents before secondary treatment were the most toxic, with TEF ≈ 700. In the reproduction test, N. spinipes was two to three times more sensitive than in the lethal test. The species most sensitive to the effluents investigated was the macroalga Ceramium strictum, with TEF values up to 3,000. The conventional effluent using a substitution of 8% ClO2 was the most toxic, and the TCF effluents were the least toxic. Degradation treatment of the ECF and TCF effluents for 28 d in the laboratory did not eliminate acute lethal effects on N. spinipes and the Microtox bacterium.
Multiple Computer-Automated structure evaluation program study of aquatic toxicity 1: Guppy
Authors: Klopman Gilles , Saiakhov Roustem , Rosenkranz Herbert S , Hermens Joop L M 
Published: March 2010

Abstract
An acute fish toxicity model was constructed on the basis of a wide series of experimental data for guppy. The Multiple Computer-Automated Structure Evaluation program was used to construct the model. The created model possesses very good predictive ability. It can correctly predict acute toxicity for guppy for 80% of compounds with an average error of only 0.63 log unit per median lethal concentration. The importance of the narcosis effect was demonstrated. The main toxicophores, corresponding to polar narcosis and to the reactive chemicals, were identified.
Methods for the diagnosis of acute 3-chloro-p-toluidine hydrochloride poisoning in birds and the estimation of secondary hazards to wildlife
Authors: Johnston John J , Hurlbut Daniel B , Avery Michael L , Rhyan Jack C 
Published: March 2010

Abstract
Female boat-tailed grackles poisoned with 3-chloro-p-toluidine hydrochloride (CPTH) were analyzed by necropsy and gas chromatography-mass spectrometry (GC-MS). The necropsies identified the presence of a white precipitate in the pericardium, which had been previously reported as a characteristic of CPTH-exposed birds. The GC-MS method, which utilized deuterated CPTH as a surrogate, quantified CPTH residues in the breast tissue and gastrointestinal tract of CPTH-exposed birds. Comparison of these techniques indicated that the GC-MS method was more accurate for assessing CPTH poisoning in birds. Regression analyses of consumption versus residue data indicated that the sum of breast and gastrointestinal residues can be used as an estimator of CPTH exposure. Comparison of CPTH residues in grackles with toxicity data for a variety of scavenger and predator species provided risk quotients of less than 0.1. Analysis of these data suggests that secondary hazards associated with the use of CPTH as an avicide for the control of pest birds are minimal.
Sensitivity of amphibian embryos and tadpoles to Mimic® 240 LV insecticide following single or double exposures
Authors: Pauli Bruce D , Coulson Donna R , Berrill Michael 
Published: March 2010

Abstract
Mimic® 240 LV is a novel, narrow-spectrum insecticide containing the active ingredient tebufenozide. Tebufenozide mimics the action of the insect molting hormone ecdysone and shows specific activity toward larval Lepidoptera. In Canada, Mimic 240 LV has been proposed for use in forest pest control, whereas a different formulation has been registered for use in agriculture. We examined the effects of single and double pulses of Mimic 240 LV (tebufenozide) on the development, growth, and predator avoidance behavior of four frog species (wood frogs Rana sylvatica, leopard frogs R. pipiens, green frogs R. clamitans, and bullfrogs R. catesbeiana) exposed in the laboratory as embryos or tadpoles. Nominal doses ranged from 3.0 mg/L to 9.0 mg/L tebufenozide, and exposures were terminated at 96 h following single, or 192 h following double, exposures. More than 90% of the animals exposed as embryos hatched. Embryos exposed late in development and subsequently hatching into tebufenozide-contaminated water all hatched and responded normally. Tadpole growth was not delayed following exposure, and premetamorphic green frogs successfully completed metamorphosis following exposure to the highest concentration. The results suggest that Mimic 240 LV, when used at the suggested application rates, will not severely affect the aquatic stages of ranid amphibians.
Vitamins A1, A2, and E in minks exposed to polychlorinated biphenyls (Aroclor 1242®) and copper, VIA diet based on freshwater or marine fish
Authors: Käkelä Reijo , Käkelä Anne , Hyvärinen Heikki , Asikainen Juha , Dahl Sanna-Kaisa 
Published: March 2010

AbstractMinks (Mustela vison) fed diets based on either freshwater fish or marine fish were exposed to 1 mg of polychlorinated biphenyls (PCBs) (Aroclor 1242®) daily for 28 d. To minks on the freshwater diet, copper (62 mg/kg food) was also given with or without PCBs. The marine diet (vitamin-rich plus additional supplements) included more vitamin A1 and E than the freshwater diet. We studied how the exposures affected levels of vitamins A1, A2, and E in liver and adipose tissues and levels of vitamins A1 and A2 in plasma. In females and males on the freshwater diet, the hepatic level of vitamin A2 was decreased because of the PCBs, and in these males the hepatic levels of vitamin E also decreased. Interestingly, with coexposure to PCBs and copper, the vitamin levels were, in general, close to the control values. In adipose tissues also, the PCBs induced significant changes in the concentrations of vitamins A1 and A2. In plasma, vitamins A1 and A2 were decreased in all patterns of exposure and on both diets. However, plasma thyroxine was slightly increased, a finding opposite to that reported previously in rodent studies. The results suggest that, in mink, diet greatly modulates the responses to PCBs, which may also differ in males and females. Furthermore, vitamins A1 and A2 may not be metabolized equally during PCB administration.
Prediction of ecotoxicity of hydrocarbon-contaminated soils using physicochemical parameters
Authors: Wong Diana C L , Chai Eric Y , Chu Karin K , Dorn Philip B 
Published: March 2010

AbstractThe physicochemical properties of eight hydrocarbon-contaminated soils were used to predict toxicity to earthworms (Eisenia fetida) and plants. The toxicity of these preremediated soils was assessed using earthworm avoidance, survival, and reproduction and seed germination and root growth in four plant species. No-observed-effect and 25% inhibitory concentrations were determined from the earthworm and plant assays. Physical property measurements and metals analyses of the soils were conducted. Hydrocarbon contamination was characterized by total petroleum hydrocarbons, oil and grease, and GC boiling-point distribution. Univariate and multivariate statistical methods were used to examine relationships between physical and chemical properties and biological endpoints. Soil groupings based on physicochemical properties and toxicity from cluster and principal component analyses were generally similar. Correlation analysis identified a number of significant relationships between soil parameters and toxicity that were used in univariate model development. Total petroleum hydrocarbons by gas chromatography and polars were identified as predictors of earthworm avoidance and survival and seed germination, explaining 65 to 75% of the variation in the data. Asphaltenes also explained 83% of the variation in seed germination. Gravimetric total petroleum hydrocarbons explained 40% of the variation in earthworm reproduction, whereas 43% of the variation in plant root growth was explained by asphaltenes. Multivariate one-component partial least squares models, which identified predictors similar to those identified by the univariate models, were also developed for worm avoidance and survival and seed germination and had predictive powers of 42 and 29%, respectively.
Lifetime pharmacokinetic model for hydrophobic contaminants in marine mammals
Authors: Hickie Brendan E , Mackay Donald , de Koning Jason 
Published: March 2010

Abstract
A physiologically based pharmacokinetic model is developed that describes the uptake and release of a hydrophobic organic chemical by a marine mammal over its entire lifetime, i.e., from birth to death. This model is applied to polychlorinated biphenyls (PCBs) in the beluga whale (Delphinapterus leucas). The processes treated are growth; uptake from food, milk, and air; disposition of the chemical among arterial and venous blood, liver, muscle, blubber, and rapidly perfused tissues; and losses by metabolism, release in exhaled air, and by egestion. A separate model is developed for females, which includes pregnancy, birth, and lactation. Food consumption is deduced from size, growth, and from activity-dependent bioenergetic data. The results obtained by simulating continuous PCB exposure over a 30-year period are in accordance with reported concentrations and show the importance of milk transfer to both mother and progeny and the tendency for continued accumulation over the animal's lifetime. Implications of the results are discussed, especially the need for improved data on diets, gut absorption characteristics, and various physiological parameters used in the model.
Environmental monitoring for linear alkylbenzene sulfonate, alcohol ethoxylate, alcohol ethoxy sulfate, alcohol sulfate, and soap
Authors: Matthijs Eddy , Holt Martin S , Kiewiet Anton , Rijs Gerard B J 
Published: March 2010

Abstract
An extensive monitoring program was executed jointly by the Dutch Soap Association (NVZ) and the Dutch authorities. Flow proportional samples of raw, settled, and treated sewage from seven representative municipal sewage treatment plants were collected over three consecutive days. The samples were analyzed for detergent surfactants, including linear alkylbenzene sulfonate (LAS), alcohol ethoxylate (AE), alcohol ethoxylated sulfate (AES), alcohol sulfate, (AS) and soap, using state-of-the-art analytical methods. All surfactants were removed by more than 99% during sewage treatment. The concentrations of the surfactants in the treated sewage averaged 39 μg/L for LAS, 6.2 μg/L for AE, 6.5 μg/L for AES, 5.7 μg/L for AS, and 174 μg/L for soap. These measured surfactant concentrations form the basis for the exposure element of the aquatic risk assessment for the surfactants studied. In addition, the field studies indicated that in-sewer removal can play a significant role in reducing the concentrations of surfactants entering the sewage treatment plant.
Effects and bioavailability of 2,4,6-trinitrotoluene in spiked and field-contaminated soils to indigenous microorganisms
Authors: Gong Ping , Siciliano Steven D , Greer Charles W , Paquet Louise , Hawari Jalal , Sunahara Geoffrey I 
Published: March 2010

Abstract
The response of potential nitrification activity (PNA), nitrogen-fixation activity (NFA), and dehydrogenase activity (DHA) in soil to 2,4,6-trinitrotoluene (TNT) was assessed. Two garden soils of contrasting texture (sandy loam vs clay loam) were spiked with TNT (25–1,000 mg TNT/kg). Soil microbial activities and TNT residues were analyzed 1 week later. The estimated IC50 (concentration causing 50% inhibition) ranged from 39 to 533 mg/kg of the acetonitrile-extractable (AE) TNT (1 week after spiking), depending on indicators and soils. The lowest LOEC (lowest-observed-effect concentration) was 1 mg AE TNT/kg. Field soil (0–15 cm) was collected from three known contaminated sites in an abandoned TNT manufacturing facility. Microbial toxicity significantly correlated to TNT levels in these soils. The LOEC and NOEC (no-observed-effect concentration) values were site and indicator specific, with the lowest LOEC being 1 mg AE TNT/kg and the lowest NOEC being 0.4 mg AE TNT/kg. The IC50 of the pooled field samples was 51 mg AE TNT/kg for PNA or 157 mg AE TNT/kg for DHA. These results indicate that microbial responses were consistent and comparable between the laboratory and the field and that TNT could significantly inhibit soil microbial activities at very low levels. Both AE TNT and deionized water–extractable (DW) TNT concentrations correlated well with microbial toxicity, but AE TNT provided a better evaluation of TNT bioavailability than did DW TNT.
Reductive dechlorination of polychlorinated biphenyls: Interactions of dechlorinating microorganisms with methanogens and sulfate reducers
Authors: Kim Jongseol , Rhee G-Yull 
Published: March 2010

Abstract
The potential role of methanogens and sulfate reducers in polychlorinated biphenyl (PCB) dechlorination was investigated using the specific inhibitors 2-bromoethanesulfonate for methanogens and molybdate for sulfate reducers and the most probable number technique. Sediments were spiked with Aroclor® 1248 (300 μg/g). The inhibition of sulfate reducers did not have any effect on Aroclor 1248 dechlorination or on the size of dechlorinating populations, which indicates that they were not directly involved. On the other hand, the inhibition of methanogens reduced the rate and extent of dechlorination but did not affect the size of dechlorinating populations. These results indicate that there are at least two different dechlorinating populations—one of which requires the presence of methanogens for dechlorination and the other of which can dechlorinate independently. In the absence of methanogenesis, meta-substituted congeners, such as 25-2′5′-, 23-2′5′-, and 25-2′-chlorobiphenyls, were not dechlorinated. When both inhibitors were added, there was no dechlorination or growth of dechlorinating microorganisms, probably because of the growth inhibition by the high redox potential stemming from the absence of the two major respirators or because of the combined effects of inhibitors themselves.
Enhanced anaerobic transformations of carbon tetrachloride by soil organic matter
Authors: Collins Richard , Picardal Flynn 
Published: March 2010

Abstract
Aaerobic, reductive dehalogenation of carbon tetrachloride (CT) by Shewanella putrefaciens 200 is enhanced by the presence of a high-organic-carbon soil. In microbial incubations without soil, 29% of the initial 3 ppm (19.5 μM) CT was transformed after 33 h, whereas 64% was transformed after only 18 h when soil was present. In sterile, biomimetic systems using a chemical reductant, 20 mM dithiothreitol, similar results were observed, suggesting that abiotic electron-transfer mediators in the soil were catalyzing the reaction. Destruction of 62% of the soil organic carbon by H2O2 resulted in a soil that was less effective in enhancing CT dechlorination. Following separation of the soil organic matter into three humic fractions, the humic acid (HA) fraction catalyzed the dechlorination reaction to a greater extent (270–442 μg of CT per gram of HA) than did the fulvic acid (FA) fraction (149–234 μg of CT per gram of FA), and both were more effective than the fraction containing humin and inorganic minerals (19–26 μg of CT per gram). The results are consistent with a mechanism involving humic functional groups that serve as electron-transfer mediators able to enhance the reductive transformation of CT in the presence of a microbial or chemical reductant. Humic functional group analyses showed that the FA contained more total acidity and carboxylic acidity than did the HA; however, both fractions contained similar amounts of total carbonyl groups and quinone carbonyls. Abiotic, HA-mediated CT transformation in the presence or absence of 20 mM dithiothreitol was found to be pH dependent. At pH 3.6, little CT transformation was observed regardless of whether dithiothreitol was present or not. At circumneutral pH, HA-mediated CT transformation required the presence of dithiothreitol. At pH 8.7, HA-mediated reductive CT transformation occurred both in the absence or presence of dithiothreitol although the transformation was greater in the presence of a reductant. Trichloromethane (chloroform [CF]) production at pH 8.7 was much lower than at circumneutral pH, and volatile organic compounds other than CF were not detected as products in any case.
Comparison of four methods of predicting newly measured octanol/water coefficients (log Kow) for heterocyclic nitrogen compounds and the partition mechanism
Authors: Li Li , Wang Liansheng , Han Shuokui , Zhang Zheng 
Published: March 2010

Abstract
Log Kow values for 14 heterocyclic nitrogen compounds (by traditional shake-flask method) were reported. Reverse phase–high-performance liquid chromatography (RP-HPLC) method and three estimation models—linear solvation energy relationship, molecular connectivity indices (MCIs), and quantum chemical descriptors—were used to study the partition mechanism and to establish the correlations of the models with the measured log Kow values by stepwise variable regression. Research on the partition mechanism showed that the molecular bulk properties and the hydrogen bond interaction were the most important factors influencing the partition process. Comparison of the quality of the models was made among the four methods. According to the simplicity of the method, the availability of the descriptors, and the closeness of correlation with the measured log Kow values, the RP-HPLC method was not satisfactory, while the MCIs method introducing the non–disperse force factor was the most satisfactoy.
Qualification of spontaneous undirected locomotor behavior of fish for sublethal toxicity testing. Part I. Variability of measurement parameters under general test conditions
Authors: Vogl Claus , Grillitsch Britta , Wytek Rudolf , Spieser O Hunrich , Scholz Wilfried 
Published: March 2010

Abstract
An automated, personal computer–based video-processing, object-recognition, and object-tracing system was used to record and analyze undirected spontaneous locomotor behavior of small groups of undisturbed semiadult zebra fish (Brachydanio rerio) in laboratory tanks. The primary data provided by the monitoring system were the individually assigned, time-stamped coordinates of the fish in two-dimensional projection. Secondary parameters (position, velocity of movement in the horizontal and the vertical direction, and temporal intraindividual and interindividual association) were calculated. The computed parameters offered a multidimensional description of spontaneous undirected swimming behavior of the fish and proved to be largely independent of water temperature, length, weight, and sex ratio of the zebra fish within the standardized range, but varied significantly with the feeding regime, time of day, number of fish per tank, and batch. Statistical characteristics of the behavioral parameters confirmed them as being appropriate for parametric statistical analyses.
Qualification of spontaneous undirected locomotor behavior of fish for sublethal toxicity testing. Part II. Variability of measurement parameters under toxicant-induced stress
Authors: Grillitsch Britta , Vogl Claus , Wytek Rudolf 
Published: March 2010

Abstract
Spontaneous locomotor behavior of semiadult zebra fish (Brachydanio rerio) was recorded under sublethal short-term exposure to the anionic technical surfactant, linear alkylbenzene sulfonate (C10–13-LAS) and cadmium in single compound tests using an automated video-monitoring and object-tracing system. Vertical position and swimming velocity in the horizontal and vertical directions were used as behavioral measurement parameters. Data were analyzed by different statistical methods. In pairwise comparisons, consistent, statistically significant, and toxicant-induced alterations of locomotor behavior were observed only for test concentrations, which also caused aspectoric symptoms of intoxication. This comparatively low sensitivity of the behavioral indication criteria was related to high variation in the measurement parameters and corresponding high, minimum detectable, statistically significant, and toxicant-induced deviations. In contrast, results obtained by regression analysis showed significant trends in locomotor activity over the range of toxicant concentrations tested. Thus, our findings support the inappropriateness of no observed effect concentrations and the lowest observed effect concentrations as summary measures of toxicity and indicate that the regression analysis approach is superior to the analysis of variance approach.
Effects of humic substances on the bioconcentration of polycyclic aromatic hydrocarbons: Correlations with spectroscopic and chemical properties of humic substances
Authors: Haitzer Markus , Abbt-Braun Gudrun , Traunspurger Walter , Steinberg Christian EW 
Published: March 2010

Abstract
The presence of dissolved humic substances (HS, fulvic and humic acids) generally reduces the up take of hydrophobic organic compounds into aquatic organisms. The extent of this effect depends both on the concentration and on the origin of the HS. The aim of this study was to investigate the role of qualitative differences between HS from different origins. The effects of seven different HS on the bioconcentration of pyrene and benzo[a]pyrene (BaP) in the nematode Caenorhabditis elegans were related to the spectroscopic and chemical properties of the HS. The effect of each humic material on the bioconcentration of pyrene or BaP was quantified as a “biologically determined” partition coefficient KDOC. We observed significant linear relationships between KDOC and the atomic H/C ratio, the specific absorptivity at 254 nm, the content of aromatic carbons (as determined by 13C nuclear magnetic resonance spectroscopy, the copper-complexing capacity, the content of phenolic OH groups, and the molecular weight of the HS. There was no discernible relationship of KDOC with the atomic (N + O)/C ratio, an indicator of the polarity of HS. Taken together, our results show that the variability in the effects of HS from different origins could be related to variations in bulk properties of the HS. Parameters describing the aromaticity of the humic materials seemed to be most useful for estimating effects of HS on the bioconcentration of pyrene and BaP.