bluuebunny/crossref_metadata_2025_split huggingface dataset:
In situ toxicity evaluations of turbidity and photoinduction of polycyclic aromatic hydrocarbons
Authors: Ireland D. Scott , Burton G. Allen , Hess George G. 
Published: March 2010

Abstract
Polycyclic aromatic hydrocarbons (PAHs) are prevalent pollutants in the aquatic environment that can cause a wide range of toxic effects. Earlier studies have shown that toxicity of PAHs can be enhanced by ultraviolet (UV) radiation. In situ and laboratory exposures with Ceriodaphnia dubia were used to evaluate photoinduced toxicity of PAHs in wet-weather runoff and in turbid conditions. Exposure to UV increased the toxicity of PAH-contaminated sediment to C. dubia. Toxicity was removed when UV wavelengths did not penetrate the water column to the exposed organisms. A significant correlation was observed between in situ C. dubia survival and turbidity when organisms were exposed to sunlight. Stormwater runoff samples exhibited an increase in chronic toxicity (reproduction) to C. dubia when exposed to UV wavelengths as compared to C. dubia not exposed to UV wavelengths. Toxicity was reduced significantly in the presence of UV radiation when the organic fraction of stormwater runoff was removed. The PAHs are bound to the sediment and resuspended into the water column once the sediment is disturbed (e.g., during a storm). The in situ and laboratory results showed that photoinduced toxicity occurred frequently during low flow conditions and wet weather runoff and was reduced in turbid conditions.
An elisa assay for cytochrome P4501A in fish liver cells
Authors: Brüschweiler Beat J. , Fent Karl , Würgler Friedrich E. 
Published: March 2010

Abstract
An enzyme-linked immunosorbent assay (ELISA) for measuring cytochrome P4501A (CY1A) expression in vitro in fish hepatoma cells is described. Cells were cultured as monolayers in 96–microwell cell culture plates and exposed to polychlorinated biphenyl (PCB) congeners 77, 105, 153, and 169; 3–methylcholanthrene (3–MC), and β-naphthoflavone (BNF) for 3 d. Relative CYP1A protein content, CYP1A enzymatic activity, and total protein content were determined directly within the wells. At low concentrations of PCB 77, PCB 169, and 3–MC, the ethoxyresorufin-O - deethylase (EROD) activity was induced, but it was inhibited at high concentrations of these compounds. However, CYP1A protein content measured in an ELISA performed with intact cells increased monotonically in response to the concentration. No CYP1A induction was observed for PCB 105 and PCB 153. Because comparison between EROD activity and CYP1A amount gives information about the catalytic efficiency of CYP1A in the cells, this noncompetitive, solid-phase ELISA is recommended as a complementary method to the EROD assay. This novel ELISA method may be an accurate in vitro technique for a rapid and sensitive screening of CYP1A-inducible compounds.
Benzo[a]pyrene hydroxylase and glutathione s-transferase activities as biomarkers in Lymnaea palustris (mollusca, gastropoda) exposed to atrazine and hexachlorobenzene in freshwater mesocosms
Authors: Baturo Wojciech , Lagadic Laurent 
Published: March 2010

Abstract
Freshwater pond mesocosms were used to validate xenobiotic-metabolizing enzymes as biomarkers of contamination by atrazine and hexachlorobenzene (HCB) in a basommatophoran gastropod, Lymnaea palustris (Müller). Over long-term (21-d) exposure to 5, 25, and 125 μg/L atrazine and to 0.5, 1.25, and 5 μg/L HCB, the uptake and internal concentration of both pesticides were followed, and the activities of benzo[a]pyrene hydroxylase (BaPH) and glutathione S-transferases (GSTs) of pesticide-exposed snails were compared with those of control animals maintained in untreated mesocosms. Internally recovered HCB concentrations were much higher than internal atrazine concentrations, but the uptake of atrazine was faster than that of HCB. Although it affected the integrity of microsomal membranes, HCB had no relevant effects on BaPH and GST activities at concentrations which affected growth and fecundity, thus confirming the low inducibility of mollusc xenobiotic-metabolizing enzymes by chlorinated compounds. In contrast, atrazine markedly inhibited BaPH and both postmitochondrial and cytosolic GSTs at the same concentrations, which had no effects on growth or reproduction. Enzyme inhibition was negatively correlated with the maximal internal amount of atrazine and positively correlated with the bioconcentration factor, suggesting that effects on xenobiotic-metabolizing enzymes may affect pharmacokinetics of atrazine within the snail body. Correlation between the bioconcentration factor and enzyme inhibition may serve as a descriptor of the physiological status of animals and can also be used to indirectly estimate the pesticide concentration in the environment. Laboratory data were considered for the interpretation of results obtained in the mesocosms. In the biomarker context, BaPH and GST activities are proposed, along with other biochemical markers already identified in atrazine- and HCB-exposed L. palustris, as elements of a multiparametric approach of the ecotoxicological effects of pesticides on freshwater ecosystems.
Evaluation of interstitial water as a route of exposure for ammonia in sediment tests with benthic macroinvertebrates
Authors: Whiteman Frank W. , Kahl Michael D. , Rau Daniel M. , Balcer Mary D. , Ankley Gerald T. 
Published: March 2010

AbstractAmmonia commonly is present at detectable concentrations in overlying and interstitial water in solid-phase sediment toxicity tests. There are scenarios in which it is desirable to discern ammonia toxicity from that caused by other contaminants. The objective of this study was to verify the technical basis for defining the bioavailability of ammonia in solid-phase sediment toxicity tests based on interstitial-(pore-) water concentrations of the compound. We compared the toxicity of ammonia in spiked-sediment versus water-only exposures with the oligochaete Lumbriculus variegatus, the midge Chironomus tentans, and the amphipod Hyalella azteca. Sediment exposures were conducted in a test system that enabled the maintenance of target concentrations of ammonia in pore water, while keeping overlying water concentrations of the compound below potential effect levels. To enable direct comparison of the water-only and sediment exposures, the same test conditions (including pH) were used for each. There was good correspondence between the LC50 values of water-only tests and spiked-sediment toxicity tests for both L. variegatus and C. tentans. Hyalella azteca apparently avoided the spiked sediments and was frequently observed in the less contaminated overlying water, thus limiting the evaluation of a pore-water exposure model for the amphipod. Overall, at least for some benthic species, ammonia bioavailability and toxicity can be accurately predicted from pore-water concentrations of the compound; however, the model maybe less robust for more epibenthic organisms, such as H. azteca.
Phytotoxicity, uptake and metabolism of 1,4-dichlorobenzene by plant cells
Authors: Jones Kevin C. , Wang Min-Jian , Bokern Maria , Boehme Christian , Harms Hans 
Published: March 2010

Abstract
Phytotoxicity, uptake, and metabolism of 14-dichlorobenzene (1,4-DCB) by carrot (Daucus carota L.), soybean (Glycine max. L.), tomato (Lycopersicon esculentum Mill.), and red goosefoot (Chenopodiun rubrum L.) cell suspension cultures were studied. Sealed glass systems were utilized for the investigation because 1,4-DCB is volatile. The sealed systems affect the growth of plant cells, but do not provide different results when testing xenobiotic uptake and metabolism. 1,4-Dichlorobenzene (40 μg in 40 ml medium) was taken up by carrot (49%), soybean (50%), and red goosefoot (62%) cells. Only the soybean cell cultures provided evidence of the existence of metabolites of this compound, probably conjugates of chlorophenols. Conditions for phytotoxicity tests were modified because the growth of cell cultures was affected when sealed for longer than 2 d. 1,4-Dichlorobenzene is toxic to cell cultures of the three tested plant species (tomato, soybean, and carrot). Concentrations of 0.5 mM caused 50% growth inhibition in carrot and soybean cultures. The tomato cultures were more sensitive, with 0.05 mM causing 50% growth inhibition.
A dynamic new alarm system for use in biological early warning systems
Authors: Sluyts Hilde , Van Hoof François , Cornet Anja , Paulussen Jozef 
Published: March 2010

Abstract
The Musselmonitor® (Delta Consult, Kapelle, The Netherlands) is a biomonitor that uses the valve position and the activity of eight Dreissena polymorpha to monitor the water quality. The normal behavior was studied to evaluate whether eight mussels are sufficient for reliable and reproducible data. The Musselmonitor was placed on a location with strong fluctuations of physical and chemical parameters. The results clearly indicate significant correlations between the valve position and the activity of the mussels and several parameters, such as temperature and concentration of suspended material (represented as turbidity and chlorophyll concentration). The valve position also indicates diurnal and seasonal rhythms in the natural behavior. A new data analyzing system was developed for the Musselmonitor, which takes into account the natural fluctuations in the behavior. The sensitivity of the dynamic data analyzing system was evaluated with copper (20, 40, 50, and 80 μg/L) in dosage experiments and the results were compared with the existing static alarm system. The study revealed that static threshold levels are insensitive and require a lot of experience. The dynamic alarm system works satisfactorily with the Musselmonitor and is very useful for the detection of discontinuities in the normal behavior.
Acute toxicity of three fire-retardant and two fire-suppressant foam formulations to the early life stages of rainbow trout (Oncorhynchus mykiss)
Authors: Gaikowski Mark P. , Hamilton Steven J. , Buhl Kevin J. , McDonald Susan F. , Summers Cliff H. 
Published: March 2010

Abstract
Laboratory studies were conducted with five early life stages of rainbow trout, Oncorhynchus mykiss, to determine the acute toxicities of five fire-fighting chemical formulations in standardized soft and hard water. Eyed egg, embryo–larvae, swim-up fry, and 60- and 90-d posthatch juveniles were exposed to three fire retardants (Fire-Trol LCG-R, Fire-Trol GTS-R, and Phos-Chek D75-F) and two fire-suppressant foams (Phos-Chek WD-881 and Silv-Ex). Swim-up fry were generally the most sensitive life stage, whereas the eyed-egg was the least sensitive. Toxicity of fire-fighting formulations was greater in hard water than in soft water for all life stages tested with Fire-Trol GTS-R and Silv-Ex and for 90-d-old juveniles tested with Fire-Trol LCG-R. The fire-suppressant foams were more toxic than the fire retardants. The 96-h median lethal concentrations (LC50s) were ranked from the most toxic to the least toxic formulation as follows (ranges are the lowest and highest 96-h LC50 calculated for each formulation): Phos-Chek WD-881 (11–44 mg/L), Silv-Ex (11–78 mg/L), Phos-Chek D75-F (218–&gt;3,600 mg/L), Fire-Trol GTS-R (207–&gt;6,000 mg/L), and Fire-Trol LCG-R (872–&gt;10,000 mg/L). Toxicity values suggest that accidental entry of fire-fighting chemicals into aquatic environments could adversely affect fish populations.
Quantitative description of mixture toxicity: Effect of level of response on interactions
Authors: Haas Charles N. , Cidambi Kaushik , Kersten Sean , Wright Kenneth 
Published: March 2010

AbstractThe simultaneous exposure of a biological system to a mixture of toxic substances may result in an ideal or nonideal combination of effects. In an extension of linear isobole theory, models are quantitatively developed to describe these combinations, in which the nature of the nonideal effect combination may or may not be a function of the magnitude of predicted response (as opposed to only the proportions of the substances in a mixture). The approach is tested using data on rat carcinogenesis, drug action, and aquatic toxicity of pesticides. In the cases examined, the models predict substantial deviation from ideal behavior even under low doses.
Factors that affect the degradation of naphthenic acids in oil sands wastewater by indigenous microbial communities
Authors: Lai June W. S. , Pinto Linda J. , Bendell-Young Leah I. , Moore Margo M. , Kiehlmann Eberhard 
Published: March 2010

Abstract
The acute toxicity of wastewater generated during the extraction of bitumen from oil sands is believed to be due to naphthenic acids (NAs). To determine the factors that affect the rate of degradation of representative NAs in microcosms containing wastewater and the acute toxicity of treated and untreated wastewater, the effects of temperature, dissolved oxygen concentration, and phosphate addition on the rate of 14CO2 release from two representative naphthenic acid substrates, (linear) U-14C-palmitic acid (PA) and (bicyclic) decahydro-2-naphthoic acid-8-14C (DHNA), were monitored. Tailings pond water (TPW) contained microorganisms well adapted to mineralizing both PA and DHNA: PA was degraded more quickly (10–15% in 4 weeks) compared to DHNA (2–4% in 8 weeks). On addition of phosphate, the rate of NA degradation increased up to twofold in the first 4 weeks, with a concurrent increase in the rate of oxygen consumption by oil sands TPW. The degradation rate then declined to levels equivalent to those measured in flasks without phosphate. The observed plateau was not due to phosphate limitation. Decreases in either the dissolved oxygen concentration or the temperature reduced the rate. Phosphate addition also significantly decreased the acute toxicity of TPW to fathead minnows. In contrast, Microtox® analyses showed no reduction in the toxicity of treated or untreated TPW after incubation for up to 8 weeks at 15°C.
Enhanced accumulation of PCB congeners by baltic sea blue mussels, Mytilus edulis, with increased algae enrichment
Authors: Gilek Michael , Björk Mikael , Kautsky Nils , Broman Dag , Näf Carina 
Published: March 2010

Abstract
The objective of this study was to examine if natural variations in the quantity of phytoplankton-derived particulate and dissolved organic carbon influences the accumulation of polychlorinated biphenyls (PCBs) in the tissues of Baltic Sea blue mussels (Mytilus edulis L.). In a laboratory flow-through experiment we exposed M. edulis to the technical PCB mixture Aroclor® 1248 for 21 d at three different enrichments of the unicellular green algae Chlamydomonas sp., 0.10, 0.16, and 0.32 mg particulate organic carbon (POC)/L. Tissue and water concentrations were determined for seven PCB congeners (International Union of Pure and Applied Chemistry [IUPAC] 52, 101, 105, 118, 138, 153, and 180), and 21-d bioaccumulation factors were calculated against total water concentrations. Contrary to what would be expected, an increase in algae enrichment from 0.10 to 0.32 mg POC/L resulted in an enhanced PCB accumulation by a factor of approx. 2. This increase in PCB accumulation was more pronounced for PCB congeners with lower hydrophobicity. These observations have implications for the design of laboratory accumulation studies and potentially for PCB accumulation and cycling in field populations of suspension-feeding mussels in response to changes in eutrophication status.
Assessing the fate of new and existing chemicals: A five-stage process
Authors: Mackay Donald , Di Guardo Antonio , Paterson Sally , Kicsi Gabriel , Cowan Christina E. 
Published: March 2010

Abstract
A five-stage process is described for obtaining an understanding of the fate of a substance after discharge to the environment and for predicting the concentrations to which organisms in various environmental media will be exposed. These five stages are: classifying the substance as to its chemical type and collecting the appropriate physical, chemical, and reactivity data based on this classification; obtaining information on the substance's past, present, and/or proposed production, use, and discharges and, if appropriate, background concentrations; conducting an evaluative fate assessment with the objective of determining the general features of the substance's behavior; conducting a regional or far-field fate evaluation using regional climatic and geographic conditions, to determine the role of environmental conditions on the substance's behavior and estimate average regional concentrations; and conducting one or more local or near-field evaluations on points of entry and other potentially impacted sites to predict the exposure concentration. With this information on fate, risk can be assessed by comparing predicted environmental concentrations with no-effect concentrations. This paper contains a detailed discussion of stage 1 (classification into one of five categories) and a discussion of how multimedia models can be used to conduct the evaluative (stage 3), regional (stage 4), and near-field (stage 5) assessments.
The accumulation in lysosomes of the anionic detergent linear alkylbenzene sulfonate
Authors: Bragadin Marcantonio , Perin Guido , Raccanelli Stefano , Manente Sabrina 
Published: March 2010

Abstract
This in vitro study provides evidence that the anionic detergent linear alkylbenzene sulfonate (LAS) enters energized lysosomes from rat liver. Because LAS is lipophilic and negatively charged, the uptake is due to the presence of a positive inside potential induced by energization of lysosomes. This accumulation could explain some damage caused by sublethal doses of detergent in some aquatic species, as it has been found that LAS inhibits lysosomal enzymes such as acid phosphatase and alkaline phosphatase.
A 7-D toxicity test for marine pollutants using the pacific mysidMysidopsis intii.1. Culture and protocol development
Authors: Langdon Chris J. , Vance Mitch M. , Harmon Valerie L. , Kreeger Karen E. , Kreeger Dan A. , Chapman Gary A. 
Published: March 2010

AbstractThe purpose of this study was to develop a short-term (7-d) toxicity test for marine pollutants that is practical to perform at sites remote from a source of test organisms. Laboratory culture methods were developed that allowed successful long-term rearing of populations of the mysid Mysidopsis intii, a species indigenous to the Pacific coast of the United States. Mysidopsis intii was found to have a short life cycle of 20 d at 20°C, making it useful for chronic toxicity tests. A 7-d toxicity test was developed by comparing the sensitivities of various life stages of M. intii to sodium dodecyl sulfate (SDS). The most sensitive end point was found to be growth (final body length) of juveniles during the first 7 d after release. The sensitivity of mysids to SDS decreased with increasing age. To allow for shipping newly released juveniles to remote sites, a 7-d test was evaluated starting with 2-d-old mysids. The median lethal concentration for M. intii exposed to SDS at ages from 2 to 9 d was 4.59 mg/L (95% confidence limits, 4.21–5.00), and the maximum acceptable SDS concentration was 4.99 mg/L for both survival and growth.
The body ion loss biomarker. 2. Field validation in coal mine-polluted streams
Authors: Grippo Richard S. , Dunson William A. 
Published: March 2010

Abstract
We performed a field validation of the body ion loss biomarker by developing a predictive model of the level of impact of coal mining on receiving streams. Hatchery brook charr (Salvelinus fontinalis; wet mass = 1.25 to 32.2 g) were exposed in four mine-impacted streams that exhibited differing levels of acid and trace metals and in two unimpacted control streams. Net whole-body ion (Na, Ca) fluxes over a 4-h exposure were determined. Stepwise regression was used to develop predictive models of body ion flux over 4 h from measured stream water chemistry variables. The predictive power of the best model was assessed using cross validation. The best model predicting net sodium flux explained 48% of the variability in the model with six chemical variables (Mn, Zn, Mg, Al, Fe, and Na). The model of calcium flux explained 42% of the variation with eight variables (H+, Ca, Na, Mn, Al, Ni, Mg, and Zn). A multiple regression model derived from principal components analysis did not significantly improve the predictive power of these models. We conclude that whole-body net sodium flux and to a lesser extent whole-body net calcium flux are acute indicators of the level of impact of acid and trace metals in streams polluted by coal mine discharge and may be useful as biomarkers under field conditions.
Ethoxyresorufin-O-deethylase induction potency of polychlorinated diphenyl ethers in H4IIE rat hepatoma cells
Authors: Koistinen Jaana , Sanderson J. Thomas , Giesy John P. , Nevalainen Tapio , Paasivirta Jaakko 
Published: March 2010

Abstract
Polychlorinated diphenyl ethers (PCDEs) are structurally similar to polychlorinated biphenyls (PCBs), and some PCDE congeners have been reported to cause toxic responses similar to those caused by some of the non-ortho-substituted PCBs, which are mediated by the aryl hydrocarbon receptor (AhR). Twenty-nine PCDEs were tested for their potency as AhR agonists relative to 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) by measuring their ability to induce the cytochrome P-450 1A1-associated enzyme activity, ethoxyresorufin-O-deethylase (EROD), in the H4IIE rat hepatoma cell bioassay. All PCDE congeners tested were found to be inactive as EROD inducers except for PCDE 156, which was a weak EROD inducer with a 2,3,7,8-TCDD equivalency factor of about 1.2 × 10−5. During this study we determined that small amounts of polychlorinated dibenzofurans (PCDFs) that occurred as impurities in the PCDE preparations were the cause of the apparent EROD induction initially measured in our experiments. Once the PCDF impurities were removed by purification on florisil, little or no activity could be attributed to the PCDEs.
Effects of acid-volatile sulfide on zinc bioavailability and toxicity to benthic macroinvertebrates: A spiked-sediment field experiment
Authors: Liber Karsten , Call Daniel J. , Markee Thomas P. , Schmude Kurt L. , Balcer Mary D. , Whiteman Frank W. , Ankley Gerald T. 
Published: March 2010

Abstract
Acid-volatile sulfide (AVS) has been proposed as the primary normalization phase for the development of sediment quality criteria for certain cationic metals. This study was designed to assist in this development by providing necessary field data on the relationships among season, AVS concentrations, and zinc bioavailability and toxicity in freshwater sediments. Zinc was spiked into uncontaminated sediments collected from a local pond, creating five simultaneously extracted metal (SEM) concentrations ranging from 0.8 to 12.0 μmol/g dry weight. The spiked sediments were transferred to 4-L plastic trays, returned to the bottom of the pond, and sampled on five dates during 1993-1994. Results revealed a pronounced increase in AVS concentration with increasing zinc concentration. Acid-volatile sulfide concentrations in zinc-spiked sediments displayed only minor seasonal variation but were lowest in surficial (0-2 cm) sediments. Acid-volatile sulfide concentrations always exceeded SEM concentrations at ≤6.0 μmol SEM/g; only at 12.0 μmol SEM/g did SEM/AVS ratios exceed 1.0. Zinc was rarely detected in pore water at any treatment and never at concentrations which should have posed a hazard to benthic macroinvertebrates. No substantial effect on colonization of zinc-spiked sediments by benthic macroinvertebrates was observed. Only oligochaetes (Naididae) were significantly reduced in abundance at the high zinc treatment, although reductions were occasionally evident for other taxa. Lack of noteworthy pore-water zinc concentrations and lack of associated, ecologically meaningful effects were attributed to the increase in AVS levels observed with increasing SEM zinc sediment concentration. The increases in AVS theoretically resulted from a replacement of natural iron and manganese sulfides with the more stable zinc sulfide complex.