bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ammonia variation in sediments: Spatial, temporal and method-related effects
Authors: Sarda Namrata , Burton G. Allen 
Published: March 2010

Abstract
In aquatic systems, ammonia is a common nutrient and pollutant that originates from both natural and anthropogenic sources. The effects of sediment and pore-water collection methods, and sediment spatial and temporal variability on ammonia concentrations, were evaluated. Sediment and pore-water collection methods included grab sampling with an Ekman dredge and hand corer followed by centrifugation, in situ suction, and in situ peeper methods. Samples were collected from three sites over a period of several months, with site replicates spaced from 30 to 60 cm and from 6 to 9 m apart. Pore-water ammonia concentrations differed significantly between the collection methods on most occasions. Ammonia concentrations were highest in the Ekman and corer pore-water samples as compared to the in situ pore waters collected from the peepers and by suction. Spatial heterogeneity in sediment ammonia concentrations was significant and generally increased with distance. Seasonal fluctuations in ammonia concentrations were evident, with high values in warmer months. Storage effects were observed with pore-water ammonia over a 1- to 4-week period. Results show that collection methods and natural variability contribute significantly to measured ammonia concentrations and are important considerations in aquatic ecosystem assessments.
A summary of the acute toxicity of 14 phthalate esters to representative aquatic organisms
Authors: Adams William J. , Biddinger Gregory R. , Robillard Kenneth A. , Gorsuch Joseph W. 
Published: March 2010

Abstract
Acute aquatic toxicity studies were performed with 14 commercial phthalate esters and representative freshwater and marine species. The 14 esters were dimethyl phthalate; diethyl phthalate; di-n-butyl phthalate; butyl benzyl phthalate; dihexyl phthalate; butyl 2-ethylhexyl phthalate; di-(n-hexyl, n-octyl, n-decyl) phthalate; di-(2-ethylhexyl) phthalate; diisooctyl phthalate; diisononyl phthalate; di-(heptyl, nonyl, undecyl) phthalate; diisodecyl phthalate; diundecyl phthalate; and ditridecyl phthalate. Phthalate esters with alkyl chain lengths of four carbon atoms or fewer were determined to be acutely toxic at concentrations ranging from 0.21 to 377 mg/L depending on the ester and the solubility of the test chemical in water. There was a general trend for the lower-molecular-weight phthalate esters (C1 to C4 alkyl chain lengths: dimethyl phthalate; diethyl phthalate; di-n-butyl phthalate; and butyl benzyl phthalate) to become more toxic with decreasing water solubility for all species tested. There were only minor differences in species sensitivity to each of the phthalate esters. Phthalate esters with alkyl chain lengths of six carbon atoms or more were not acutely toxic at concentrations approaching their respective aqueous solubilities. Insufficient mortality occurred to calculate either LC50 or EC50 values or acute no-observed-effect concentrations for these higher-molecular-weight phthalate esters. The lack of toxicity observed for the higher-molecular-weight phthalate esters resulted from their limited water solubility (≤1.1 mg/L).
Polychlorinated biphenyls (PCBs) depress allogeneic natural cytotoxicity by earthworm coelomocytes
Authors: Suzuki Michael M. , Cooper Edwin L. , Eyambe George S. , Goven Arthur J. , Fitzpatrick Lloyd C. , Venables Barney J. 
Published: March 2010

Abstract
Coelomocytes of the earthworm Lumbricus terrestris caused significant spontaneous allogeneic cytotoxicity in a 24-h trypan blue assay, but not in an assay using lactate dehydrogenase (LDH) release. Allogeneic cytotoxicity assays using cells from worms exposed to polychlorinated biphenyls (PCBs) suggest that PCBs can suppress a natural killing (NK-like) reaction. The implications of this work are twofold: understanding the evolution of natural killing (NK-like) activity and providing preliminary information on how spontaneous killing, a component of cellular immunity, may be compromised by pollutants.
Synergistic effect of flyash and SO2 on development of cucumber (Cucumis sativus L.) leaf injury
Authors: Tung Gabrielle , McIlveen William D. , Jones Randall D. 
Published: March 2010

Abstract
In a two-factorial experiment, sulfur dioxide alone at concentration of 131 μg/m3 over long exposures or flyash from either coal or oil combustion alone applied onto cucumber (Cucumis sativus L.) foliage causes no visible injury. However, if both flyash and sulfur dioxide were presented simultaneously, a specific mosaic-chlorosis symptom developed on leaves. A synergistic effect was thus demonstrated. Histopathology of the mosaic-chlorosis symptom was studied. An unusual pattern of tissue abnormally initiated from the collapse of the anticlinal cell walls of the upper epidermal cells and progressed along cell walls into mesophyll tissues. Cellular injury at the lower spongy tissues typical of that caused by SO2 was also observed. A significant elevation of sulfate-sulfur in the leaves treated with a combination of SO2 and flyash was demonstrated. Significant interactions between the two factors were found for both injury and sulfur chemistry. This suggests that flyash deposits on the leaf surface play a catalytic role in oxidizing atmospheric sulfur dioxide continuously to form sulfuric acid (H2SO4) in situ. This acid could infiltrate into mesophyll damage cells and tissues en route.
Evaluation of lipid-containing semipermeable membrane devices for monitoring organochlorine contaminants in the Upper Mississippi river
Authors: Ellis Geoffrey S. , Rostad Colleen E. , Huckins James N. , Schmitt Christopher J. , Petty Jimmie D. , Maccarthy Patrick 
Published: March 2010

Abstract
Organochlorine contaminants sequestered in lipid-containing semipermeable membrane devices (SPMDs) were compared to those found in tangential-flow ultrafilter permeates as part of a pilot study at 10 sites in the Upper Mississippi River system. Caged and feral fish from three primary sites were also analyzed for comparison. Concentrated organochlorine (OC) compounds were readily extracted from the SPMDs by dialysis into hexane, and samples were analyzed by gas chromatography-negative chemical ionization-mass spectrometry. Fish and water samples were processed by conventional methods. Reasonable agreement was found between analyte SPMD-derived water concentrations and measured values of ultrafilter permeates; however, concentrations of the same analytes in caged fish did not appear to be proportional to water concentrations derived from SPMDs and ultrafilter permeates. The greatest number of OC compounds was detected in SPMDs; fewer were detected in caged fish and feral fish.
Comparative fate of [14C]trichloroethylene in the root zone of plants from a former solvent disposal site
Authors: Anderson Todd A. , Walton Barbara T. 
Published: March 2010

Abstract
A comparison of the environmental fate of [14C]trichloroethylene ([14C]TCE) in vegetated and nonvegetated soils from a contaminated field site indicated increased mineralization (14CO2 production) in soils containing vegetation. Mineralization in soils containing Lespedeza cuneata (Dumont), Pinus taeda (L.), Solidago sp. (all collected from a former chlorinated solvent disposal site), and Glycine max, germinated from commercially available seeds, accounted for &gt;26% of the total recovered radioactivity compared with approximately 15% for nonvegetated soil and &lt;9% for control (sterile) soil. Uptake of 14C into plant tissues ranged from 1 to 21% total for leaves (or needles), stems, and roots and appeared to be related to plant species and water use during the experiment. The higher mineralization rates for [14C]TCE in the vegetated soils compared with nonvegetated soils indicates that the rhizosphere provides a favorable environment for microbial degradation of organic compounds. Therefore, vegetation may play an important role in enhancing biological remediation of contaminated surface soils in situ.
Toxicity of aspen wood leachate to aquatic life: Laboratory studies
Authors: Taylor Barry R. , Goudey J. Stephen , Carmichael N. Bruce 
Published: March 2010

Abstract
Trembling aspen (Populus tremuloides Michx.), a common hardwood tree throughout Canada, is being harvested at increasing rates for use in paper and building materials. Piles of aspen logs have been observed to produce a dark, watery, acutely toxic leachate. A laboratory study was undertaken to elucidate the nature, strength, and persistence of aspen leachate toxicity and the chemical composition of the leachate. Leaching from aspen chips in the laboratory was rapid, with 1% mass loss in the first 24 h. Another 2 weeks of immersion was necessary to remove all remaining leachable material (3% total). Fresh aspen leachate derived from a 1:9 wood-water mixture (35 d immersion) was characterized by amber color, low pH (4.0), extremely high BOD (&gt;2,600 mg/L), and high conductivity (1140 μS/cm). The leachate was rich in phenols (30 mg/L), organic carbon (2,480 mg/L), and organic nitrogen (13 mg/L). Median acutely toxic concentrations of leachate were consistently 1 to 2% of full strength for trout and Daphnia. Inhibition of bacterial metabolism began at concentrations below 0.3%. Leachate was less toxic to plant life but inhibited algal growth at concentrations of 12 to 16%. Toxicity of aspen leachate persisted at the same level as in fresh leachate for more than 2 months unless artificial aeration was provided. Persistence was even greater at low temperature (5°C). Aged leachate underwent a transition marked by a rise in pH and dissolved oxygen concentration, a small decline in conductivity, and a color change, from amber to black. Toxicity declined abruptly when the supply of labile toxicants was exhausted, but it sometimes increased again from the products of microbial metabolism. Oxygen depletion, low pH, and phenolic compounds contribute to the toxicity of aspen leachate, but much of the toxic effect must be attributed to other, unidentified constituents.
Gas chromatography-mass spectrometry analysis of the herbicide clopyralid in differentially cultivated soils
Authors: Schütz Stefan , Weißbecker Bernhard , Hummel Hans E. 
Published: March 2010

Abstract
The herbicide clopyralid offers a high selectivity in thistle control using low application rates. Contradictory results in soil leaching experiments using this herbicide indicate the need for a reliable procedure for trace analysis of clopyralid. The problem of poor extraction efficiency from soil that is rich in humic substances was solved by ultrasound-enhanced alkaline extraction. Analysis of the extract was performed by gas chromatography-mass spectrometry after derivatization with pentafluorobenzylbromide in an ultrasound-enhanced phase-transfer catalytic reaction. Tetrabutylammoniumbromide served as a phase-transfer catalyst. For improving analytical reliability, 2,5-dichlorobenzoic acid was used as an internal standard. The achieved detection (1 μg/kg = 1 ppb) and quantification (10 μg/kg) limits of clopyralid in soil were appropriate for determining the degradation behavior in herbicide-treated soils. The half-life of clopyralid in two differentially cultivated soils was determined in laboratory trials. Uncultivated soil that was rich in humic acids showed a higher half-life than cultivated soil.
Effects of low ph on the uptake and distribution of 54Mn(II) in brown trout (Salmo trutta)
Authors: Rouleau Claude , Tjälve Hans , Gottofrey James 
Published: March 2010

Abstract
Goups of seven fish were exposed for 21 d to 0.1 μg 54Mn L−1 at pH 5.3 and 7.5. At the end of the experiment, the whole-body 54Mn concentration offish held in water at pH 5.3 was significantly higher (1.7 times) compared to fish held at pH 7.5. A similar increase was observed in viscera, brain, and eyes. These results suggest that higher Mn levels found in fish living in acidic waters may not only depend on the higher total Mn concentrations usually found in these waters.
Use of Rodeo® and X-77® spreader to control smooth cordgrass (Spartina alterniflora) in a southwestern washington estuary: 1. Environmental fate
Authors: Paveglio Fred L. , Kilbride Kevin M. , Grue Christian E. , Simenstad Charles A. , Fresh Kurt L. 
Published: March 2010

Abstract
A 1-ha plot with smooth cordgrass (Spartina alterniflora) at three locations in Willapa Bay, a southwestern Washington estuary, was aerially treated with 4.7 L/ha Rodeo® and 0.9 L/ha X-77® Spreader to determine the fate of the herbicide formulation. Rates of spray deposit on filter pads placed over treated intertidal mudflats did not differ among locations for glyphosate and aminomethylphosphonic acid (AMPA); however, deposit rates for nonylphenol polyethoxylates (NPEO) did differ among locations. Glyphosate concentrations in sediment cores from treated mudflats declined 51 to 72% during 119 days posttreatment (DPT); NPEO concentrations in sediment declined (42%) between spray day and 14 DPT. The highest concentrations of glyphosate, AMPA, and NPEO in seawater were found in off-site samples collected from the leading edge of the first high tide after application. Glyphosate and AMPA concentrations in depth-integrated seawater samples declined 73 and 42%, respectively, between the first high tide immediately following application and the second high tide at 1 DPT. Glyphosate concentrations in Spartina stems from treated plots declined 91 to 99% between 1 and 28 DPT; whereas, AMPA declined (86 and &gt;96%) during this period. Comparison of maximum concentrations for glyphosate in seawater from this study with acute toxicity values in the literature indicates that under worst-case conditions direct effects to aquatic organisms would not be likely.
Toxicological benchmarks for screening contaminants of potential concern for effects on freshwater biota
Authors: Suter G. W. 
Published: March 2010

Abstract
An important early step in the assessment of ecological risks at contaminated sites is the screening of chemicals detected on the site to identify those that constitute a potential risk. Part of this screening process is the comparison of measured ambient concentrations to concentrations that are believed to be nonhazardous, termed “benchmarks.” This article discusses 13 methods by which benchmarks may be derived for aquatic biota and presents benchmarks for 105 chemicals. It then compares them with respect to their sensitivity, availability, magnitude relative to background concentrations, and conceptual bases. Although some individual values can be shown to be too high to be protective and others are too low to be useful for screening, none of the approaches to benchmark derivation can be rejected without further definition of what constitutes adequate protection. The most appropriate screening strategy is to use multiple benchmark values along with background concentrations, knowledge of waste composition, and physico-chemical properties to identify contaminants of potential concern.
Inorganic polyphosphates in the developing freshwater sponge Ephydatia muelleri: Effect of stress by polluted waters
Authors: Imsiecke Georg , Münkner Jessica , Lorenz Bernd , Müller Werner E. G. , Schroder Heinz C. , Bachinski Nilza 
Published: March 2010

Abstract
Relatively high amounts of inorganic polyphosphates (approximately 55 μg of polyphosphate/g of wet weight) were found in the freshwater sponge Ephydatia muelleri, particularly in the gemmules (260 μg/g). Here we report that the polyphosphate content of this sponge changes during development and in response to adverse environmental conditions. Germination and hatching of gemmules of E. muelleri is accompanied by a strong decrease (by 94% at day 2) in polyphosphate level and a rise in exopolyphosphatase activity. On the other hand, induction of gemmulogenesis by theophylline results in an increase (by 61%) in polyphosphate content of sponge tissue. An increase in polyphosphate content and a decrease in exopolyphosphatase activity also occur during tissue regression when hatched sponges are exposed to polluted water from river. Nonionic organic compounds extracted from this water were identified as contaminants causing a rise in polyphosphate content of E. muelleri. The results show that measurement of polyphosphate level may be a promising method to detect responses of the freshwater sponge to polluted waters.
Effects of a nonionic surfactant (C14–15AE-7) on aquatic invertebrates in outdoor stream mesocosms
Authors: Gillespie William B. , Rodgers John H. , Crossland Norman O. 
Published: March 2010

Abstract
Responses of aquatic invertebrates to a C14–15 linear alcohol ethoxylate (LAE) nonionic surfactant with an average of seven ethylene oxide units per mole of alcohol were evaluated in outdoor stream mesocosms. Two experiments were carried out to evaluate responses of aquatic invertebrates to 28- and 30-d exposures in eight stream mesocosms. Changes in benthic invertebrate densities and in invertebrate drift were monitored during pretreatment, treatment, and posttreatment periods. In Experiment 1, mean measured concentrations of surfactant were 0.08, 0.16, and 0.33 mg LAE/L. In Experiment 2, mean measured concentrations were 0.11, 0.28, and 0.55 mg LAE/L. In each experiment, there were two treated streams at each surfactant concentration and two untreated streams that served as controls. No significant effects (p &gt; 0.05) on population densities of Copepoda, Cladocera, Chironomidae, Nematoda, or Annelida were observed in either experiment. Moreover, no effects were detected on the numbers of any of these organisms collected in drift nets. However, there was a significant decrease (p ≤ 0.05) in the densities of Simuliidae at surfactant concentrations ≥0.16 mg LAE/L. This was accompanied by an increase in the numbers of Simuliidae collected in drift nets. Based on these results, the no-observed-effect concentration for aquatic invertebrates was 0.08 mg LAE/L, and the lowest-observed-effect concentration was 0.16 mg LAE/L.
Lyophilization of thylakoids for improved handling in a bioassay
Authors: Zimmermann Gitta M. , Kramer Gerard N. , Schnabl Heide 
Published: March 2010

Abstract
The thylakoid bioassay is used to determine the effect of herbicides in water. To avoid isolation for each bioassay, lyophilization of thylakoids for continuous, reproducible supply as bioassay material is descibed. This technique maintains the photosynthetic activity after lyophilization at 82 ± 9% (n = 5) of its original level.
Toxicity of organic mixtures containing cyanogenic toxicants
Authors: Chen Chung-Yuan , Huang Chi-Feng 
Published: March 2010

Abstract
In this study we evaluated the joint actions of cyanogenic toxicants with other organic chemicals using Microtoxx® tests. Experimental results indicated that greater than additive effect seldom occurred when these chemicals were mixed with nonreactive toxicants. However, the likelihood of synergistic effects exceeded 30% when reacting with a reactive chemical. Among the cyanogenic toxicants investigated in this study, malononitrile, lactonitrile, and α-hydroxy-isobutyronitrile have an approx. 50% likelihood of acting via synergism mode with other reactive toxicants. On the other hand, the joint actions related to acetonitrile and allyl cyanide are either additive or less than additive. Moreover, the likelihood of encountering synergistic effects markedly increases if the slopes of the dose–response curves for the two chemicals tested are small. Therefore, slope and certain characteristics of a chemical structure can apparently be used as indices to assess the potential hazard for a specific organic mixture. Furthermore, the complex joint action exerts a certain deterministic influence over the joint action mode of cyanogenic toxicants. This type of joint action, which quite frequently leads to an obvious antagonistic or even detoxification phenomena, could have some useful toxicological and pharmacological applications. Lastly, estimating the mixture toxicity on the basis of the concentration addition model is not always appropriate considering the high percentage of cases in this study showing synergism.
Effects of exposure to an organophosphorus pesticide on the behavior and use of cover by captive starlings
Authors: Fryday Steven L. , Hart Andrew D. M. , Langton Stephen D. 
Published: March 2010

Abstract
It has been suggested that reduced behavioral activity of birds exposed to anticholinesterase pesticides could bias measures of exposure in field studies if the worst-affected individuals were underrepresented in samples collected by shooting or netting. To assess the likely scale of such biases, European starlings (Sturnus vulgaris) were housed in large aviaries containing simulated bushes made from natural vegetation. Each bird was given a near-lethal dose of the organophosphorus pesticide chlorfenvinphos, and the proportion of time spent in and out of cover was recorded before and after treatment. Use of cover by exposed birds increased significantly 0 to 7 h after treatment, whereas feeding and flying activity decreased. On the following day, there was little difference in the use of cover by exposed and control birds. Mathematical models were used to estimate the effect of these behavioral changes on the sampling of birds from wild populations. The results confirm the potential for sampling bias to occur after acute pesticide exposure. This bias is reduced in samples taken over 24 h after exposure, but delayed samples are unlikely to be representative of cholinesterase (ChE) inhibition at the time of maximal effect. When poisoned birds seek cover, it is more difficult to find casualties in field trials and the probability that dead birds will be found and recorded in wildlife casualty monitoring schemes is reduced. We conclude that considerable caution is required in using ChE activity as an indicator of exposure in avian field trials.
Effects of different formulations of granular pesticides on birds
Authors: Stafford Tamara R. , Best Louis B. , Fischer David L. 
Published: March 2010

Abstract
Fensulfothion was formulated on granular pesticide carriers to evaluate the effects of carrier type (silica, clay, and corncob), pesticide load per granule (½, ⅛, and 1/32 of the LD50), granule size (0.2 to 0.6 and 1.0 to 1.4 mm), and granule color (white and blue) on avian risk from granular pesticides. Carrier type and pesticide load per granule were evaluated in a separate experiment from granule size and color. In both experiments, captive house sparrows (Passer domesticus) were offered the granular pesticide formulations in bands on soil surfaces. Bird behavior, body weight, survival, and brain and plasma cholinesterase activity were used to assess pesticide exposure. Silica and clay carrier types posed a greater risk to birds than corncob granules. Exposure also was greater with a higher pesticide load per granule. Findings were inconclusive regarding the effect of granule size and color on avian exposure to granular pesticides. Precipitation seemed to increase the possibility of dermal exposure to the pesticide. It is important to consider factors in addition to those used currently by the U.S. Environmental Protection Agency when evaluating the risk to birds from granular pesticides.