bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of three concentrations of mixed fatty acids on dechlorination of tetrachloroethene in aquifer microcosms
Authors: Gibson Susan A. , Roberson D. Scott , Russell Hugh H. , Sewell Guy W. 
Published: March 2010

Abstract
Chloroethenes are among the most common organic contaminants of ground water. The biotransformation of these compounds by reductive dechlorination is a promising technology for in situ treatment. The effects of three concentrations of a fatty acids mixture on the reductive dehalogenation of tetrachloroethene (PCE) were studied in methanogenic microcosms. These microcosms were constructed with slurries of aquifer solids collected from an area impacted both by aviation gasoline and chlorinated ethenes at Traverse City, Michigan. The microcosms were amended with approximately 30 μM PCE and one of three concentrations (0.1, 1, or 10 mM total acids) of a mixture of low-molecular-weight organic acids, or were part of a control set that received no amendment. The observed lag or adaptation times before the onset of PCE dehalogenation were 51 d (10 mM acids), 65 d (1 mM acids), 86 d (0.1 mM acids), and &gt;233 d (no acids). After 233 d of incubation, no PCE was detectable in any of the fatty-acid-supplemented microcosms, but 23 to 27 μM of combined tri- and dichloroethenes (TCEs, DCEs) was detected. PCE was not dechlonnated in microcosms without a fatty acid supplement. Although there were observed differences in the length of the lag time, the amount of ultimately dechlorinated PCE was similar. A zero-order rate constant of 0.3 μM d−1 was calculated for PCE dechlorination and for TCE dechlorination for the two series of microcosms receiving 0.1 and 1.0 mM fatty acid supplements. Of the fatty acids tested in the mixture, butyrate oxidation appeared to be the most probable link to PCE dechlorination.
Microbial potential for the anaerobic degradation of simple aromatic compounds in sediments of the Milwaukee Harbor, Green Bay and Lake Erie
Authors: Myers Charles R. , Alatalo Laura J. , Myers Judith M. 
Published: March 2010

Abstract
The ability of microbial populations to mediate the anaerobic transformation of six aromatic compounds in sedi ments from the Milwaukee Harbor, Green Bay, and Lake Erie was examined Sediment slurries were incubated in an anaerobic mineral salts medium that was amended with multiple electron acceptors, including manganese(IV) and Fe(III) oxides, and the concentrations of the aromatic substrates were followed over a six to 18 month period Most sediment samples showed a com plete loss of benzoate and 4 hydroxybenzoate within approximately two months Benzoate losses were partially to markedly inhibited by the addition of molybdate, whereas losses of 4 hydroxybenzoate were not molybdate inhibited Significant losses of aniline, 3 chlorobenzoate, and 2,4-dichlorophenoxyacetic acid were observed with many of the sediments after approximately 18 months Molybdate markedly inhibited the metabolism of 3 chlorobenzoate with all sediments, and of aniline with some sed lments Increases in free chloride, which are indicative of reductive dechlorination were coincident with losses of 3 chlorobenzoate and 2,4 dichlorophenoxyacetic acid No significant metabolism of 4 chlorobenzoate was apparent in any of the sediments Over all, the results indicate that microbes with the ability to degrade at least certain aromatic compounds are present at various sites within these environments
Polychlorinated dibenzo-P-dioxins and dibenzofurans in mya arenaria in the newark/raritan bay estuary
Authors: Brown Richard P. , Cooper Keith R. , Cristini Angela , Rappe Christoffer , Bergqvist Per-Anders 
Published: March 2010

Abstract
The objectives of this study were to examine the bioavailability, bioaccumulation, and elimination of several poly-chlorinated dibenzo-p-dioxins and dibenzofurans in the soft-shell clam, Mya arenaria Linneaus. Clams were collected from three sites in the Newark/Raritan Bay estuary (Newark, NJ; Elizabeth, NJ; Wards Point, NY), from Little Egg Harbor (Tuckerton, NJ), and from the Chesapeake Bay (Prince Frederick, MD). Collections were made between 1986 and 1990, and samples were prepared for isomer-specific analysis. Clams from the Newark site contained TCDD concentrations that ranged from 11 to 20 parts per trillion (pptr), from the Elizabeth site 4.8 to 10 pptr, and from Wards Point 0.5 to 1.1 pptr. Clams collected from Tuckerton and Chesapeake Bay ranged from 0.1 to 0.6 pptr. Transplantation of clams from Chesapeake Bay into the Elizabeth site resulted in bioaccumulation of dioxins and furans to concentrations comparable with the natural Elizabeth population by three months post-transplant. Transplantation of soft-shell clams from the Elizabeth into the Tuckerton site resulted in elimination of dioxins and furans to concentrations comparable with the natural Tuckerton population within four months post-transplant. The calculated half-life of elimination for TCDD was 45 d, for TCDF 111d, and for I-TEF 66 d.
Modeling the reactions of 1-naphthylamine and 4-methylaniline with humic acids: Spectroscopic investigations of the covalent linkages
Authors: Ononye Aloysius I. , Graveel John G. 
Published: March 2010

AbstractThe covalent binding of two aromatic amines, 1-naphthylamine and 4-methylaniline, to substituted quinones in aqueous solutions has been studied as a model for the covalent binding of amines to humic acids. An inline compound was the only type of product identified for the reactions between 1-naphthylamine and selected quinones. Reactions of 4-methylaniline with the same quinones gave a 1,4- addition product in addition to the imine compound, although only the imine product was formed when the quinone had bulky substituents at the 2- and 6- positions. These results provide additional insight into the reactions of aromatic amines with humic acid quinones.
Assessing acute toxicities of pre- and post-treatment industrial wastewaters with Hydra attenuata: A comparative study of acute toxicity with the fathead minnow, Pimephales promelas
Authors: Fu Li-Jie , Staples Robert E , Stahl Ralph G 
Published: March 2010

Abstract
This study was undertaken to (a) determine wastewater treatment effectiveness using two freshwater organisms (b) compare acute toxicity results from the two species exposed to the wastewaters, and (c) link acute and potential develop mental toxicity of wastewaters in one organism The acute toxicities of several pretreatment and post treatment industrial waste water samples were evaluated with adult Hydra attenuata (92 or 96 h exposure) and fathead minnows (96 h exposure) The acute LC50s agreed closely when results in Hydra attenuata were compared with those from fathead minnow tests Acute LC50s ranged from 3 to &gt; 100% of sample with hydra, and from 1 0 to &gt; 100% of sample with fathead minnows The results provided strong evidence of treatment effectiveness because toxicity decreased with progressive stages of treatment Previously the Hydra Developmental Toxicity Assay (Hydra Assay) was used as a prescreen mainly for in vitro assessment of developmental toxicity with pure compounds and to prioritize toxicants according to selective toxicity to the developing embryo (A/D ratio) Recently we modified the assay for testing natural waters and wastewaters, hence, some of the wastewater samples also were tested for their developmental toxicity In this case, the relative selective toxicity (A/D ratio) of these wastewater samples ranged from 0 7 to 2 1, indicating that no sample was uniquely toxic to the developing embryo, although acute toxicity was manifested Over all, our results indicate the Hydra Assay functions appropriately in assessments of acute and developmental toxicity of industrial wastewaters and may be a simple and useful tool in a battery of tests for broader scale detection of environmental hazards
Temporal changes in lead levels in common tern feathers in New York and relationship of field levels to adverse effects in the laboratory
Authors: Burger Joanna , Lavery Meredith Horoszewski , Gochfeld Michael 
Published: March 2010

Abstract
In this paper we examine lead levels in the feathers of adult common terns (Sterna hirundo) from 1978 to 1992, compare them to values for other species breeding in the same or nearby colonies from one year (1989), and contrast these levels with those associated with sublethal behavioral and physiological effects in the lab. Lead levels in feathers of common tern decreased significantly from 1978 through 1985, were stable until 1988, and then increased through 1992. The mean levels of lead in feathers of roseate tern (Sterna dougallii), herring gull (Larus argentatus), and black skimmer (Rynchops niger) were slightly higher than those for common terns in 1989. Levels in feathers of some individuals of all species in the wild were within the range associated with behavioral impairment and growth retardation in the lab.
Phytoplankton colonization and seasonal succession in new experimental ponds
Authors: Rosenzweig Michael S. , Buikema Arthur L. 
Published: March 2010

Abstract
Following the U.S. Environmental Protection Agency's specifications for pesticide registration tests, 12 experimental ponds were constructed. Colonization and succession of the pond phytoplankton communities were investigated during the first year after filling. Taxon richness and densities and biomass as chlorophyll-a were measured. In addition, water-quality data were collected and analyzed. The dominant taxonomic groups were the Cyanophyceae, Chlorophyceae (with Desmidiaceae dominating), Dinobryon (in the Chrysophyceae), Dinophyceae, and Bacillariophyceae. Similar successional patterns in all 12 ponds occurred; however, the community structure between ponds was not similar at any time. Although the ponds had statistically similar environmental characteristics, they varied in their community structure, indicating that after one year they were not mature enough for use as replicate test systems. The heterogeneity of the pond phytoplankton communities indicates that meso-cosms need to be managed to produce replicate experimental units.
Lysozyme activity in earthworm (Lumbricus terrestris) coelomic fluid and coelomocytes: Enzyme assay for immunotoxicity of xenobiotics
Authors: Goven Arthur J. , Chen Shing Chong , Fitzpatrick Lloyd C. , Venables Barney J. 
Published: March 2010

Abstract
Lysozyme activity in earthworm (Lumbricus terrestris) coelomic fluid and coelomocytes appears sufficiently sensitive for use as a nonmammalian biomarker to detect toxic effects of sublethal body burdens of Cu2+ (28.5 ± 2.67 and 73.1 ± 5.68 μg/g dry mass). Lysozyme, a phylogenetically conserved enzyme, is capable of bactericidal activity via action on peptido-glycan of gram-positive bacterial cell walls and functions as a component of an organism's innate antimicrobial defense mechanism. Coelomic fluid and coelomocyte lysozyme activities, which exhibited temperature-response patterns similar to those of human saliva, plasma, serum and leukocyte extracts, were sensitive to Cu2+ exposure. Lysozyme activity of coelomic fluid and coelomocyte extracts from earthworms exposed for 5 d to CuSO4, using filter paper contact exposure, decreased with increasing sublethal Cu2+ concentrations of 0.05 and 0.1 μg/cm2. Compared to controls, coelomic fluid lysozyme activity was suppressed significantly at both exposure concentrations, whereas coelomocyte extract lysozyme activity was suppressed significantly at the 0.1-μg/cm2 exposure concentration. Low inherent natural variability and sensitivity to sublethal Cu2+ body burdens indicate that lysozyme activity has potential as a biomarker for assaying immunotoxicity of metals.
Interactive effects between EBI fungicides (prochloraz, propiconazole and penconazole) and OP insecticides (dimethoate, chlorpyrifos, diazinon and malathion) in the hybrid red-legged partridge
Authors: Johnston Gail , Walker Colin H. , Dawson Alistair 
Published: March 2010

AbstractThe toxicokinetic interactions between the ergosterol-biosynthesis-inhibiting (EBI) fungicides prochloraz, propicon-azole, and penconazole and the organophosphorus (OP) insecticides dimethoate, chlorpyrifos, and diazinon have been studied in the hybrid red-legged partridge. The inhibition of serum butyrylcholinesterase (BuChE) activity provided a useful biochemical indicator of the generation of the toxic oxon metabolites of these OP insecticides. Birds pretreated with 180 mg/kg prochloraz tended to show a greater inhibition of serum BuChE activity at 1, 4, and 24 h following oral exposure to either of the OPs dimethoate (3 mg/kg) or chlorpyrifos (9 mg/kg) compared to birds pretreated with corn oil. Prochloraz-pretreated birds also showed a tendency toward an increased inhibition at 24 h following dosing with the OP diazinon (4.3 mg/kg) compared to corn oil controls. In the case of dimethoate, the inhibition of serum BuChE activity was significantly greater in treated birds than controls at 24 h. Birds pretreated with the EBI fungicide propiconazole (200 mg/kg) showed a similar inhibition of serum BuChE activity to those pretreated with corn oil following administration of 167 mg/kg malathion. Pretreatment with the EBI fungicide penconazole (200 mg/kg) produced significantly greater depression of serum BuChE activity at 1, 4, and 24 h after dosing with malathion, when compared to corn oil controls. The tendency toward increased inhibition of serum BuChE activity by each of the OPs in prochloraz-pretreated birds was attributed to an increased activation of the compound to its active oxon form as a consequence of induction of microsomal monooxygenases by prochloraz.
Comparative effects of oil dispersants to the early life stages of topsmelt (Atherinops affinis) and kelp (Macrocystis pyrifera)
Authors: Singer Michael M , George Saji , Jacobson Susan , Lee Ina , Tjeerdema Ronald S , Sowby Michael L 
Published: March 2010

AbstractThe acute effects of two oilspill dispersants were compared using the early life stages of two common nearshore marine organisms the topsmelt (Athennops affinis), a common fish in bays and estuaries, and the giant kelp (Macrocystis pyrifera), a canopy forming brown alga Testing was done under closed, flow through conditions, with spiked dispersant concentrations measured in real time using UV spectrophotometry Both dispersants were composed of complex mixtures of anionic and nonionic surfactants and solvents Median effect concentration data showed Athennops tests to be more sensitive to both dispersants than Macrocystis tests, with values ranging from 48 2 to 72 9 ppm (LC50) and 73 0 to 79 4 ppm (IC50), respectively, for Nokomis® 3, and from 43 7 to 45 8 ppm (LC50) and 73 0 to 95 9 ppm (IC50), respectively, for Slik A Way A different pattern was seen in NOECs, in which both species showed significantly higher sensitivity to Slik A Way than to Nokomis 3 (α = 0 05) Comparison of the present data with those previously compiled for the same products with two other species the red abalone (Hahotis rufescens) and a mysid (Holmesimysis costata), showed fairly consistent interspecific patterns among three of the four species, Holmesimysis tests were seen to be least sensitive to Nokomis 3 and second most sensitive to Shk A Way In addition, Shk A Way was more toxic to all species except Macrocystis
Effects of low concentrations of forest-use pesticides on frog embryos and tadpoles
Authors: Berrill Michael , Bertram Susan , McGilliray Lise , Kolohon Mark , Pauli Bruce 
Published: March 2010

Abstract
Management of coniferous forests of eastern Canada may involve spraying with the insecticide femtrothion and the herbicides triclopyr and hexazinone Because ranid frogs breed in ponds that are unavoidably contaminated by spraying, we measured the toxicity of these chemicals to embryos and tadpoles of Rana pipiens (leopard frog), Rana clamitans (green frog), and Rana catesbeiana (bullfrog) under lab conditions Embryos were exposed during late neurula stage and tadpoles within 48 h after hatching to femtrothion (24 h, 0 5-8 0 ppm), tnclopyr (48 h, 0 6-4 8 ppm), and hexazmone (8 d, 100 ppm) We measured hatching success of embryos, and for tadpoles, mortality, ability to swim away when prodded, and total body length one week after exposure Hexazinone had no effects on embryos or tadpoles, even at the unreasonably high levels to which they were exposed Hatching success of embryos and subsequent avoidance behavior were unaffected in all species by exposures to triclopyr and femtrothion Newly hatched tadpoles of all species were very sensitive to 2 4 and 4 8 ppm tnclopyr and to 4 0 and 8 0 ppm femtrothion, either dying or remaining paralyzed following exposure Tadpoles initially affected by exposure to lower concentrations of femtrothion or tnclopyr usually recovered within 1 to 3 d Bullfrog and green frog tadpoles appear to be more sensitive than leopard frog tadpoles, and bullfrog tadpoles were consistently more sensitive than green frog tadpoles
Predicting chronic lethality of chemicals to fishes from acute toxicity test data: Concepts and linear regression analysis
Authors: Mayer Foster L , Krause Gary F , Ellersieck Mark R , Lee Gunhee , Buckler Denny R 
Published: March 2010

AbstractA comprehensive approach to predicting chronic lethality from acute toxicity data was developed in which simultaneous consideration is given to concentration, degree of response, and time course of effect A consistent end point (lethality) and degree of response (0%) were used to compare acute and chronic tests Predicted NOECs were highly accurate 84 to 92% of the time (within a factor of 2 0 of the limits of the maximum acceptable toxicant concentrations for lethality) and did not vary by more than a factor of 3 6 97% of the time when the technique was applied to a database of 18 chemicals and seven fish species Growth effects can be predicted from chronic lethality, but reproductive or other chronic effects should not
Substrate- and nutrient-limited toluene biotransformation in sandy soil
Authors: Allen-King Richeixe M. , Barker James F. , Gillham Robert W. , Jensen BjøRn K. 
Published: March 2010

Abstract
Lab microcosm tests of the rate of toluene biodegradation were performed using soil from the A, B, and C horizons of the unsaturated zone of a sandy field site. Most of the soil samples had been previously exposed to toluene. Toluene biodegradation was rapid, occurring at a time scale comparable to the rate of sorption in many of the microcosms and demonstrating the potential for bioremediation of these contaminants in unsaturated soil. In the A horizon, with an initial toluene concentration in the solution phase of 4.5 mg/L, degradation was controlled by substrate-limited growth on toluene as the primary substrate. Soil from the B and C horizons initially showed similar behavior with a lower toluene concentration of about 2.5 mg/L. The maximum utilization rate (μmax) for soil from all three depths was 2.0 d−1. With repeated exposure to moderate to high concentrations of toluene, transformation in the B- and C-horizon soil appeared to be zero order, at a rate of 1.0 to 2.0 μg tol-uene/g soil/d. In C-horizon soil that had been taken directly from the field, the transformation rate was almost immeasurably slow. Addition of nitrogen as either ammonium or nitrate accelerated the degradation, showing that nitrogen was the most limiting nutrient.
The apparent adaptation period observed before rapid toluene removal was fit by a substrate-limited growth model. Greater numbers of toluene-degrading microorganisms were found in soil exposed to toluene than in unexposed soil, supporting bio-mass growth as the explanation for the adaptation period. The results of enumeration of heterotrophs compared to the numbers of toluene degraders suggested that a small proportion of the total viable microorganisms were responsible for degradation of toluene.
Synchronous fluorometric measurement of metabolites of polycyclic aromatic hydrocarbons in the bile of brown bullhead
Authors: Lin Edith L. C. , Cormier Susan M. , Racine Richard N. 
Published: March 2010

AbstractA synchronous fluorescent spectroscopy (SFS) method was developed to measure pyrene-type metabolites in the bile of brown bullhead (Ameiurus nebulosus) and to estimate the exposure of fish to PAHs in four Lake Erie tributaries collected in the spring and fall of 1990 and 1991. For comparison, fish biliary benzo[a]pyrene (B[a]P) metabolites were also measured by HPLC/fluorescent detection (HPLC/F). Both methods showed that concentrations of biliary PAH metabolites of fish collected in polluted rivers were significantly higher than those collected from reference rivers. Concentrations of biliary metabolites of fish caught in the Black River were five to 20 times greater than those collected in Old Woman Creek by SFS and three to five times greater by HPLC/F. Fish from the Cuyahoga River had four to 24 times more biliary PAH metabolites than fish from Old Woman Creek, measured by SFS, and five to 10 times more, measured by HPLC/F. Brown bullhead from the Tous-saint River had fewer PAH metabolites than fish from Old Woman Creek. Correlation analyses of the two sets of data obtained by SFS and HPLC/F showed significance by both Pearson's sample correlation and Spearman's rank correlation. This study indicates that pyrene-type metabolites determined by SFS can be used to estimate B[a]P-type metabolites in fish bile. SFS appears to be a highly sensitive method for detecting PAH metabolites and, because of its simplicity, a cost-efficient method for screening large numbers of samples for exposure to PAHs in fish.
Mercury pollution in doha (Qatar) coastal environment
Authors: Al-Madfa H. , Dahab O. Aboul , Holail H. 
Published: March 2010

Abstract
Surface water and sediment samples were collected from the Doha coastal area and analyzed for content of physico-chemical forms of mercury. Dissolved reactive Hg (2.9 ng L−1) represented 81.0% of the total dissolved Hg (3.5 ng L−1). Organic Hg (0.6 ng L−1) contributed only 5.0% of total Hg. Mercury showed a strong tendency to be associated with suspended matter in Doha coastal waters, as it represented about 73.0% of the total. Total Hg in bulk Doha surface sediments fluctuated between 0.14 and 1.75 μg g−1 dry weight, with an average of 0.54 ± 0.46 μg g−1 dry weight. The sediment fraction past 63 μm contained 0.73 μ0.60μg g−1 dry weight total Hg. Leachable and methyl Hg averaged 0.10 ± 0.11 and 0.02 ±0.03 μg g−1 dry weight, respectively, in the &lt;63-μm sediment fraction. There is a general trend for all Hg species determined in water and sediments to decrease seaward. The significantly elevated Hg levels at certain locations indicated that the main Hg sources to Doha coastal environment are leachate from the solid waste disposal site, the two harbors, and surface-water discharge.