bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relative induction of aryl hydrocarbon hydroxylase by 2,3,7,8-TCDD and two coplanar PCBs in rainbow trout (oncorhynchus mykiss)
Authors: Janz David M. , Metcalfe Chris D. 
Published: March 2010

AbstractRelative aryl hydrocarbon hydroxylase (AHH) induction potencies of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and the two coplanar PCB congeners 3,3′,4,4′-tetrachlorobiphenyl (IUPAC congener 77) and 3,3′,4,4′,5-pentachlorobiphenyl (IUPAC congener 126) were determined in rainbow trout (Oncorhynchus mykiss). Trout were injected intraperitoneally with chemicals dissolved in corn oil. The ED50 for AHH induction in TCDD-injected fish was 0.005 μmol/kg. The ED50s for PCB congeners 126 and 77 were 1.0 μmol/kg and 2.2 μmol/kg, respectively. AHH toxic equivalent factors (AHH-TEFs), or TCDD equivalents, were determined as the ratio of the TCDD ED50 to the ED50 for each PCB congener. AHH-TEFs for congeners 126 and 77 were 0.005 and 0.002, respectively. Toxic equivalent quantities for AHH induction (AHH-TEQs) were calculated by multiplying the TCDD equivalent for each chemical by its concentration in fish at environmental levels. AHH-TEQs, based on whole-body TCDD and PCB concentrations in Lake Ontario rainbow trout, were two- to threefold greater for the coplanar PCBs than for TCDD. Although these data do not necessarily indicate that coplanar PCBs are highly toxic to fish, the results indicate that these compounds have the potential to contribute to the environmental effects of compounds structurally related to TCDD.
Use of fractionation procedures and extensive chemical analysis for toxicity identification of a chemical plant effluent
Authors: Jop Krzysztof M. , Kendall Timothy Z. , Askew Ann M. , Foster Robert B. 
Published: March 2010

Abstract
As a part of a National Pollutant Discharge Elimination System (NPDES) biomonitoring program a series of toxicity tests was conducted with process water from a chemical plant using Ceriodaphnia dubia and Pimephales promelas. There were marked differences among the two tested species. The acute (LC50) values from 96-h static toxicity tests with Pimephales promelas were always lower (higher toxicity) than the values obtained from the invertebrate tests. The concentration of ammonia in the effluent, particularly its un-ionized form (250 mg NH4-N/L, which represents 0.7 mg NH3-N/L), was above the threshold concentration for most freshwater species and therefore was the primary suspect of the toxicity present in the effluent.
Prior to initiation of the toxicity identification evaluation (TIE) program, chemical analyses that included measurements of inorganic and organic parameters were conducted with the effluent. During the TIE fractionation, a portion of the sample was purged with nitrogen to remove volatile organics, and a second portion of the sample was pressure-filtered through a 0.45-μm filter. Because toxicity equal to the whole sample was found in these fractions, a portion of the inorganic fraction was subfractionated into zeolite, clinoptilolite, activated carbon, pH-adjustment, aeration, and cation fractions. The results of these tests confirmed that ammonia played a role in the sample's toxicity. However, when ammonia was removed from the effluent sample, toxicity was still present. Next organic chemicals were fractionated as suspected sources of toxicity. At first, organics were removed from the effluent by passing the filtered sample over an XAD-resin column. Because a portion of the reconstituted organic fraction was toxic, the organic fraction was subfractionated further by extracting with dichloromethane at pH &gt; 11, pH &lt; 2, and pH 7.1. The dichloromethane extracts were toxic, whereas the aqueous portions were not toxic. The neutral extract, which was more toxic than the basic and acidic extract, was further fractionated by using HPLC. Seventeen HPLC fractions were isolated and tested for toxicity to determine which constituent(s) were responsible for the observed whole effluent toxicity.
Polycyclic aromatic hydrocarbons and mutagens in ambient air particles sampled in Thessaloniki, Greece
Authors: Viras L. G. , Siskos P. A. , Samara C. , Kouimtzis TH. , Athanasiou K. , Vavatzanidis A. 
Published: March 2010

Abstract
Seventy samples of airborne particulates were sampled from two sites in Thessaloniki, Greece, during the period of one year, starting in July 1987. Thessaloniki is located in the northeastern part of Greece and is the second most highly populated city of the country. The 24-h samples were taken by using high-volume samplers located in two monitoring sites — 1 and 2. Site 1 was located at the center of the city (main pollution sources were traffic and central heating), whereas site 2 was in the industrial zone of the city (main sources were industrial activities and traffic). The collected particulates were examined for their mutagenicity with the Ames test. The analysis of particulates to determine their content in polycyclic aromatic hydrocarbons (PAHs) was done by the gas chromatographic method. The column used to separate the various PAHs was a wide-bore capillary column. Ten PAHs were identified and quantified in the atmosphere of Thessaloniki. No essential differences were found between the mean values of PAH concentrations measured at the two sites, whereas the mutagenicity values at site 1 (central area) were higher than those measured at site 2 (industrial site). The PAH concentrations were moderate if compared with those found in other polluted cities in the world, whereas the mutagenic activity of particulates was low. Higher values of PAH concentrations and mutagenicity were found during winter. During Sundays the PAH concentrations were lower than those measured on weekdays. No significant linear correlation was found between PAH concentrations and mutagenicity for both sites of measurements. The main sources of PAHs were estimated to be the stationary sources in winter and the traffic in summer for both measuring sites. Higher values of both PAH concentrations and mutagenicity were found during days with light winds.
Nitroblue tetrazolium dye reduction by earthworm (lumbricus terrestris) coelomocytes: An enzyme assay for nonspecific immunotoxicity of xenobiotics
Authors: Chen Shing Chong , Fitzpatrick Lloyd C. , Goven Arthur J. , Venables Barney J. , Cooper Edwin L. 
Published: March 2010

Abstract
Earthworm (Lumbricus terrestris) coelomic leukocytes, or coelomocytes, were shown to have sufficient ability to reduce nitroblue tetrazolium dye (NBT) for potential use as a surrogate biomarker to assess nonspecific immunotoxicity of environmental xenobiotics. NBT reduction is used clinically to evaluate potential of human leukocytes to oxidatively kill phagocytosed microorganisms. Coelomocyte NBT reduction, which exhibited time–response patterns similar to those of human and murine neutrophils and murine macrophages, was sensitive to Cu and/or Pb contaminants in refuse-derived fuel fly ash (RDFF). NBT reduction by coelomocytes from earthworms exposed for 5 d to RDFF:commercial soil mixtures decreased significantly with increasing sublethal RDFF concentrations of 10, 30, 50, and 70%. Compared to soil-exposed controls, dye reduction was significantly suppressed in all but the 10% RDFF group: 40, 59, and 64% of controls, respectively. Differences were significant among experimentals, except between 50 and 70% RDFF. Tissue levels of Cu and Pb accorded with RDFF exposure concentrations in which suppression of NBT reduction occurred. NBT reduction was not significantly suppressed in coelomocytes from earthworms exposed to 70% fly ash that had been acid-washed to remove metals.
Allozymic variability in toxicity-testing strains of ceriodaphnia dubia and in natural populations of Ceriodaphnia
Authors: Snyder Thomas P. , Switzer Kristen M. , Keen Robert E. 
Published: March 2010

Abstract
Ceriodaphnia dubia Richard used in 7-d chronic toxicity testing from six environmental testing centers were assayed for allozymic variability at 11 enzymatic loci. Ten of the eleven scored loci were monomorphic and homozygous in all six stocks. One stock was homozygous for an alternative electromorph, as compared to the other five, at the glucose-6-phosphate dehydrogenase (G6PDH) locus. Laboratory stocks comprise two morphologically distinguishable forms of Ceriodaphnia dubia that may be environmentally determined. Ceriodaphnia lacustris and Ceriodaphnia reticulata from natural populations showed within- or between-population allozymic variability at 8 of the 11 loci, suggesting Ceriodaphnia possesses genetic variability equivalent to that of other cladocerans. The three species of Ceriodaphnia are closely related, having only one diagnostic electromorph that separates Ceriodaphnia dubia from the other two species. Possible causes of the monomorphism of the laboratory stocks are discussed.
Response of polyamines to heavy metal stress in oat seedlings
Authors: Wettlaufer S. H. , Osmeloski J. , Weinstein L. H. 
Published: March 2010

Abstract
Polyamine titers in oat seedlings (Avena sativa L.) were evaluated as possible biomarkers for heavy metal stress. The titers were measured in response to the addition of 20 metal salts. Six of those metal salts were chosen for further study: chromium, cobalt, copper, mercury, nickel, and silver. Changes in polyamine titer in response to the addition of the six metal salts were specific for each metal, but were generally smaller when compared to changes in polyamine titer associated with other forms of plant stress reported in the literature. Changes in putrescine titer, over time, were also specific for each metal, but did not correlate well with the changes in the enzymatic activity of its biosynthetic enzyme, arginine decarboxylase. We conclude that polyamine metabolism and arginine decarboxylase activity are not effective as general biomarkers for evaluating heavy metal stress in oat seedlings.
Mutagenicities of hydroxy-substituted carbazoles and dibenzothiophenes using the CHO/HGPRT assay
Authors: Rasmussen Kathy , Booth Gary M. , Lee Milton L. , Castle Raymond N. 
Published: March 2010

Abstract
Eight hydroxylated carbazoles and dibenzothiophenes were tested for mutagenic activity using the CHO/HGPRT mutation assay for thioguanine resistance. All showed increased activity over carbazole and dibenzothiophene. Some of the hydroxycarbazoles showed slightly higher activity than the corresponding hydroxy-dibenzothiophenes (71.4 ± 5.2 mutants/106 survivors for 1-hydroxycarbazoles compared to 21.8 ± 6.1 mutants/106 survivors for 4-hydroxydibenzothiophene at 5 μg/ml, and 32.8 ± 3.3 mutants/106 survivors at 5 μg/ml for 4-hydroxycarbazole as compared to 16.4 ± 0.9 mutants/106 survivors for 1-hydroxydibenzothiophene at 5 μg/ml). The most mutagenic compound was 1-hydroxycarbazole, which also exhibited cytotoxicity. The relative order of mutagenic activity of the hydroxycarbazoles was 1 ≥ 4 &gt; 2 = 3 &gt; carbazole, and the relative activity of the hydroxydibenzothiophenes was 2 ≥ 3 &gt; 1 = 4 &gt; dibenzothiophene. Overall, the mutagenic activity of the hydroxycarbazoles and hydroxydibenzothiophenes was dependent on the structural position of the hydroxy group.
Sensitivity of bacterioplankton in the Rhine river to various toxicants measured by thymidine incorporation and activity of exoenzymes
Authors: Tubbing Diny M.J. , Admiraal Wim 
Published: March 2010

Abstract
Natural populations of bacteria in water samples from the lower Rhine River were tested for their sensitivity to selected toxicants. Bacterial growth, measured as [3H-methyl] thymidine incorporation, was affected by additions of 5 μg Cu L−1; these concentrations were similar to the copper concentrations found in the river. Concentrates of the organic fraction from river water, obtained via XAD-columns, affected thymidine incorporation in samples of river water when added in concentrations corresponding to ambient levels. The exoenzymatic activities of phosphatase and protease decreased systematically at concentrations higher than 5 μg Cu L−1. Potassium dichromate (K2Cr2O7) at a concentration of approximately 3 mg L−1 and a detergent tetrapropylbenzene sulfonate (TPBS) at a concentration of 5 mg L−1 had detectable effects on microbial activity. Atrazine affected the growth rate but not the enzymatic activity of bacterial populations when this herbicide was added in concentrations of 50 to 200 μg L−1. Thymidine incorporation was more sensitive to all test compounds than the enzymatic activities. It is concluded that the present pollution levels, although decreased, are still likely to affect microbial processes in the river.
Variability in the performance of the seven-day fathead minnow (pimephales promelas) larval survival and growth test: An intra- and interlaboratory study
Authors: Degraeve G. M. , Cooney J. D. , Mcintyre D. O. , Pollock T. L. , Reichenbach N. G. , Dean J. H. , Marcus M. D. 
Published: March 2010

Abstract
The U.S. Environmental Protection Agency (EPA) has developed a “Seven-Day Fathead Minnow Larval Survival and Growth Test” for measuring the toxicity of effluents. This study evaluated the ease and performance and the intra- and interlaboratory variability of this 7-d test using two reference toxicants (sodium pentachlorophenate and potassium dichromate), two refinery effluents, and one low-volume internal waste stream from an electric power plant. Ten different laboratories representing academia, private industry, contractors, the state EPA, and the U.S. EPA participated in this study. The reference toxicants were tested twice during two separate test periods, and each effluent and waste stream was tested once. Using EPA's criteria for a successful test, 90% of the 140 planned tests were completed as valid tests. The intralaboratory variability of the survival (LC50) and growth (IC50) results for tests conducted concurrently (spatial variability), expressed as the coefficient of variation (C.V.), ranged between 5.9 and 15.6% and between 9.1 and 26.1%, respectively. The intralaboratory variability of the survival (LC50) and growth (IC50) results for tests conducted at two different times (temporal variability), expressed as C.V., ranged between 14.5 and 25.3% and between 17.6 and 22.7%, respectively. The interlaboratory variability of the survival (LC50) and growth (IC50) results, expressed as C.V., ranged between 24.1 and 43.7% and between 22.4 and 88.0%, respectively. Overall, the variability of the 7-d fathead minnow test was similar to the variability observed with other toxicity tests and with analytical chemistry measurements of environmental samples.
The european system of standardized legal tests for assessing the biodegradability of chemicals
Authors: Nyholm Niels 
Published: March 2010

Abstract
A brief overview is given of the approach to biodegradation testing adopted by the European Economic Community (EEC) as part of the legislation on new chemicals. The tiered system of screening and simulation tests is outlined and the various tests are discussed briefly. It is concluded that the test strategy is logical and cost-effective, but that ongoing work to further harmonize and revise screening tests for ready biodegradability must be completed before these tests perform satisfactorily. The principles governing simulation tests should be further developed, and, in particular, the importance of the applied concentration of test chemical should be addressed.
Silica encapsulation reduces bioavailability
Authors: Pier Stanley M. , Gallo Michael A. , Umbreit Thomas H. , Connor Thomas H. , Gray Donald , Cappelleri Frank A. 
Published: March 2010

Abstract
Lead chromate pigments can be encapsulated within an amorphous silica coating. This reduces both the chemical teachability and the biological availability of the constituents. The chromate moiety is inactive in in vitro mutagenicity assays, even in the presence of a strong chelating solubilizer under conditions where the unencapsulated material gives positive results. Rodent feeding studies demonstrate much reduced absorption of both lead and chromium from the encapsulated lead chromate compared to the analogous unencapsulated material. Encapsulation also reduces the leachability of both lead and chromium in tests used to define the applicable environmental disposal methods for lead chromate pigments. These findings have important implications for health and environmental issues surrounding the use of lead chromate as a pigment material.
Bond contribution method for estimating henry's law constants
Authors: Meylan William M. , Howard Philip H. 
Published: March 2010

Abstract
Bond contribution values, used to estimate Henry's law constant (HLC) (air-to-water partition coefficient) from chemical structure, have been determined for 59 chemical bonds by a least-square analysis of known HLCs for 345 organic compounds. A correlation coefficient (r2) of 0.94 was determined for the relationship between known LWAPCs (log water-to-air partition coefficients) and bond estimated LWAPCs for the 345 compound data set. The correlation coefficient increases to 0.97 when quantified correction factors are applied to selected chemical classes. The ability of the bond method to estimate LWAPCs is demonstrated by a validation test set of 74 diverse and structurally complex compounds that were not included in the least-squares analysis. The correlation coefficient for the validation set is 0.96.
Acid-volatile sulfide as a factor mediating cadmium and nickel bioavailability in contaminated sediments
Authors: Ankley Gerald T. , Phipps Gary L. , Leonard Edward N. , Benoit Duane A. , Mattson Vincent R. , Kosian Patricia A. , Cotter Anne M. , Dierkes Joseph R. , Hansen David J. , Mahony John D. 
Published: March 2010

Abstract
We investigated the influence of sulfide, measured as acid-volatile sulfide (AVS), on the bioavailability of cadmium and nickel in sediments. Seventeen samples from an estuarine system heavily contaminated with cadmium and nickel were analyzed for AVS and simultaneously extracted metals (SEM) and tested in 10-d exposures with the amphipod Hyalella azteca and the oligochaete Lumbriculus vanegatus. Molar SEM (cadmium + nickel)/AVS ratios in the sediments ranged from less than one to greater than 200, with several in the range of 1 to 10. Samples with SEM/AVS ratios greater than one were consistently toxic to Hyalella azteca, whereas sediments with ratios less than one were not. Lumbriculus variegatus was less sensitive to the test sediments than Hyalella azteca, which was consistent with their relative sensitivity to cadmium and nickel in water-only exposures. SEM/AVS ratios in the sediments also appeared to be important in determining bioaccumulation of metals by Lumbriculus variegatus. These results support other studies with metal-spiked samples in demonstrating the importance of AVS in determining metal bioavailability in sediments and suggest that AVS normalization is a reasonable means for assessing the hazard of some sediment-associated metals to aquatic ecosystems.
Differences in acute toxicity test results of three reference toxicants on Daphnia at two temperatures
Authors: Lewis Philip A. , Horning William B. 
Published: March 2010

Abstract
Ten 48-h static acute toxicity tests were conducted with Daphnia magna Straus and Daphnia pulex Leydig with each of the three reference toxicants — sodium dodecyl sulfate (SDS), sodium pentachlorophenate (NaPCP), and cadmium (Cd) (as CdCl2) — at 20 and 26°C to investigate the effect of temperature on test results at the temperature extremes usually encountered during field studies. The mean 48-h LC50 value for SDS with Daphnia pulex at 26°C was lower (10.2 mg/L) than at 20°C (12.6 mg/L), but the difference was not significant (α = 0.05). For Daphnia magna the mean LC50 was significantly (α = 0.05) lower at 26°C (10.8 mg/L) than at 20°C (13.5 mg/L). Sensitivity of either species to NaPCP was not significantly different (α = 0.05) at the two temperatures. The data show a fourfold increase in sensitivity to Cd at the higher temperature with Daphnia magna (mean LC50 = 0.038 mg/L at 20°C and 0.009 mg/L at 26°C) and a sevenfold increase with Daphnia pulex (mean LC50 = 0.042 mg/L at 20°C and 0.006 mg/L at 26°C). These data indicate that toxicity tests conducted at 20 and 26°C may give significantly different results with Daphnia. Because test precision, control survival, and the likelihood of obtaining valid tests are better at 20°C, that temperature is recommended for acute toxicity tests with Daphnia.
Effects of spiked exposure to an oil dispersant on the early life stages of four marine species
Authors: Singer Michael M. , Smalheer Deborah L. , Tjeerdema Ronald S. , Martin Michael 
Published: March 2010

Abstract
Spiked exposure, continuous flow toxicity tests using the oil dispersant Corexit 9527® were performed during the early life stages of four California marine species. Test chambers containing sensitive life stages of the giant kelp (Macrocystis pyrifera), the red abalone (Haliotis rufescens), a kelp forest mysid (Holmesimysis costata), and the topsmelt (Atherinops affinis) were inoculated with concentrated dispersant, then allowed to flush with clean, filtered seawater Spectrophotometric monitoring of tests showed dispersant levels diminishing to below detection limits within 5 to 6 h or less Results showed Hahotis to be the most sensitive species tested, with Atherinops being least sensitive in terms of no-observed effect concentration (NOEC) and Holmesimysis being least sensitive in terms of median effect concentration, Macrocystis was intermediate in both measures. When spiked exposure toxicity results were compared to those of previously reported constant-exposure tests, no consistent conversion factor that might relate spiked- and constant-exposure toxicity data was found.
Collection of ammonia in indoor air by means of a weak cation exchange cartridge
Authors: Risner C. H. , Conner J. M. 
Published: March 2010

Abstract
An active sampling method based on a solid-phase collection medium was used to determine ammonia concentrations in indoor air. A weak cation exchange cartridge was used to collect ammonia, which was then eluted from the cartridge with 0.02 M HCl and determined by cation exchange chromatography (CEC) with conductivity detection. The method was applied to quantify the ammonia in environmental tobacco smoke (ETS) and is compared to an impinger collection technique. The method was reproducible with a relative standard deviation of 2.0%. Percent recovery is about 98%. Analyses of samples collected in a variety of situations showed that ammonia concentrations vary. With a relatively short sampling time of 0.5 to 1 h, this procedure was capable of detecting ammonia above 5 μg m−3 under the sampling conditions.
Sensitivity to uranium of six species of tropical freshwater fishes and four species of cladocerans from Northern Australia
Authors: Bywater John F. , Banaczkowski Robyn , Bailey Megan 
Published: March 2010

Abstract
The toxicity of uranium to the tropical freshwater fishes —black-banded rainbowfish (Melanotaenia nigrans), chequered rainbowfish (Melanotaenia splendida inornata), Mariana's hardy-head (Craterocephalus marianae), delicate blue-eye (Pseudomugil tenellus), reticulated perchlet (Ambassis macleayi), and purple-spotted gudgeon (Mogurnda mogurnda) — and the cladocerans — Diaphanosoma excisum, Latonopsis fasciculata, Dadaya macrops, and Moinodaphnia macleayi — was measured under standard conditions in natural creek water. The fishes' 96-h LC50s for uranium were 1.7 and 1.9 mg/L for 7- and 90-d-old black-banded rainbowfishes, 2.66 and 3.46 mg/L for 7- and 90-d-old chequered rainbowfishes, 1.22 mg/L for Mariana's hardyhead, 0.73 mg/L for delicate blue-eyes, 0.8 mg/L for reticulated perchlet, and 1.11 and 1.46 mg/L for 7- and 90-d-old purple-spotted gudgeon. The cladocerans' 24-h LC50s for uranium were 1.0 mg/L for Diaphanosoma excisum, 0.41 mg/L for Latonopsis fasciculata, 1.10 mg/L for Dadaya macrops, and 1.29 mg/L for Moinodaphnia macleayi. Larval purple-spotted gudgeon, reticulated perchlets, and Moinodaphnia macleayi were identified as the most suitable species for toxicity testing.