bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of surface films on the fate of deltamethrin following aerial application to prairie ponds
Authors: Muir Derek C. G. , Yarechewski Alvin L. , Neal B. Richard 
Published: March 2010

Abstract
The dissipation of the insecticide deltamethrin was studied in natural prairie ponds (0 3–1 3 ha, 1–1 5 m depth) following aerial application Four ponds were treated at normal field rates (7 5 g/ha) with deltamethrin, two in June 1986 and two others in June 198− Parts per billion concentrations of deltamethrin were observed in the surface microlaver (0 12 mm, sampled with a glass plate) in all treatments during the first 8 to 12 h after application Levels of deltamethrin were about 1000-fold lower in subsurface water (10–20 cm depth) Pseudo first order half-lives of deltamethrin in the surface film varied from 0 6 to 5 h and were influenced by macrophvte density and amount of sprav deposit Half-lives of deltamethrin in subsurface waters were less variable, averaging 14 h Deltamethrin was not detected in sediments (0–2 5 cm depth containers, detection limit 10 ng/g dry weight) following sprav application in either year The stereoisomer (α R, 1R/α S 1S-cis-) was detected in subsurface water along with a cyclopropvl acid derivative (DBCA) and phenoxybenzoic acid (PBA) Concentrations of DBCA and PBA 10 to 100 fold higher than that of the parent compound persisted in subsurface water for 18 to 25 d after spray deposition The surface film influenced the overall fate of deltamethrin by reducing diffusive transport to subsurface waters and increasing the amount of the insecticide available for volatilization and degradation
Time effects on enzyme activity in the mosquitofish, Gambusia Holbrooki
Authors: Heagler M. G. , Mulvey M. 
Published: March 2010

Abstract
A study to examine the maximum interval between time of death and enzymatic sampling was conducted to determine the appropriate interval to procure reliable data from electrophoretic analysis of mosquitofish, Gambusia holbrooki. Dead fish were sampled at regular time intervals (0, 8, 12, 24 hours) and electrophoresed. All 26 of the enzyme systems assayed were reliably scorable 8 hours after death, with a large number remaining scorable up to 24 hours after death.
A simple method of pH control for static and static-renewal aquatic toxicity tests
Authors: Mount David R. , Mountz Donald I. 
Published: March 2010

AbstractIn response to the need for pH control in aquatic toxicity tests we developed methods to control pH by manipulating the carbon dioxide concentration in the atmosphere over test solutions We believe the use of CO, is preferable to other types of pH control advantages include less alteration of normal test solution chemistry and use of a natural buffer system to achieve ongoing pH control Physical requirements for the use of this method and currently known limits of its use are described Several methodological variations are discussed, along with example applications of the technique
Fate and biological effects of contaminated vegetation in a tennessee stream
Authors: Stewart A. J. , Haynes G. J. , Martinez M. I. 
Published: March 2010

Abstract
Potamogeton foliosus (an aquatic plant) and filamentous algae from a settling basin with contaminated sediment became enriched with polychlorinated biphenyls (PCBs), Co, Cd, Cu, Hg, Ni, Mn, U, and Zn During the growing season, large amounts of the contaminated Potamogeton foliosus and algae were exported downstream from this basin to East Fork Poplar Creek (EFPC) We used drift nets to estimate the loading rates of the plants to EFPC, analyzed samples of the plants for metals, and conducted a series of experiments with snails (Elimia clavaeformis), amphipods (Gammarus sp), and a microcrustacean (Ceriodaphnia dubia) to evaluate the possible effects of inputs of the vegetation to EFPC biota Little of the vegetation that entered the stream was transported intact as far as 1 4 km During the growing season, inputs of organic carbon to this 1 4-km segment of stream due to the deposition of the plants were at least 2 4 times greater than autochthonous production Thus the vegetation was bioenergetically important to at least a 1 to 3-km reach of EFPC The experiments showed that all three types of animals could distinguish between contaminated (CON) and noncontaminated (NC) Potamogeton foliosus Snails preferred the NC plants over the CON plants, these animals also had lower growth rates on CON plants than on NC plants Amphipods preferred CON plants over NC plants in a 48-h experiment, but preferred NC plants over CON plants in a 7 d experiment Leachates prepared from CON Potamogeton foliosus were toxic to Ceriodaphnia, those prepared from NC Potamogeton foliosus were not Energy-subsidy and/or contaminated food aspects of the Potamogeton inputs could help explain why pollution sensitive invertebrates such as mayflies and stoneflies are not present in EFPC immediately downstream from the settling basin
Genetic indicators of environmental stress in central mudminnow (Umbra Limi) populations exposed to acid deposition in the Adirondack Mountains
Authors: Kopp Richard L. , Guttman Sheldon I. , Wissing Thomas E. 
Published: March 2010

Abstract
Horizontal starch gel electrophoresis was used to characterize the genetic structure of central mudminnow (Umbra limi) populations from acid stressed (low pH/high Al) and nonacid-stressed sites in the north branch of the Moose River (NBMR), New York, in order to determine if environmental shifts were accompanied by detectable shifts in genetic structure Central mudminnow populations in the NBMR were characterized by significantly (p ≥ 0 05) lower heterozygosity levels at stressed sites (H (mean number of heterozygotes per locus per individual) = 0 060 0 102) than reference sites (H = 0 130, 0 142) Additionally, several genetic loci demonstrated either consistent (isocitrate dehydrogenase, phosphogluconate dehydrogenase) or moderately consistent (glucose 6 phosphate isomerase 1 malate dehydrogenase-1, mannose-6 phosphate isomerase) genotypic shifts in comparisons between populations at reference and low pH/high Al sites Populations at acid stressed sites were characterized by higher frequencies of one particular allozyme, suggesting that environmental conditions were acting as a selective force In acute laboratory toxicity tests (pH, 4 5, Al, 7 5 mg/L), the most tolerant fish were significantly more genetically variable, indicating that genetic diversity may be beneficial to the survival of individual fish experiencing physiological stress
Effects of aqueous and dietary exposure of dieldrin on survival, growth and bioconcentration in mallard ducklings
Authors: Nebeker Alan V. , Griffis William L. , Stutzman Thomas W. , Schuytema Gerald S. , Carey Lori A. , Scherer Susan M. 
Published: March 2010

Abstract
Tests were conducted to determine the effects of dieldrin in continuous flow water and in food on survival, growth, and bioconcentration in mallard ducklings (Anas platyrhynchos) Di eldrin had no effect on survival or growth at concentrations at or below water saturation (0 2 mg/L), but tissue (lipid, skin, liver, muscle, brain, blood) dieldrin concentrations increased rapidly (up to a mean of 217 μg/g) and bioconcentration factors (BCFs) showed up to 1,995 times (mean steady state lipid BCF of 1,345) more dieldrin in tissues than in the water Significant effects on survival, growth, and behavior were observed in ducks fed dieldrin spiked food, and tissues rapidly concentrated dieldrin up to five times more than those in the water-only test (mean of 1,000 μg/g), although the BCFs were much lower (water BCFs were up to 18 times higher) The dietary 96 h LC50 value (50% death at 96 h) was 165 μg/g dieldrin, the 24-d dietary LC50 was 29 5 μg/g The lowest 24 d LOAEL (lowest observed adverse effect level) and NOAEL (no observed adverse effect level) values were 16 4 and 0 3 μg/g, respectively, based on growth (total weight) A screening level wildlife criteria (SLWC) value of 0 0001 mg/L was derived by using data from this study Steady-state tissue dieldrin concentrations at which growth impairment occurred were near 140 (lipid), 80 (skin), 20 (liver), 10 (brain), and 5 (muscle) μg/g dieldrin Tissue dieldrin concentrations where no growth impairment was observed were near 3 0 (lipid), 1 0 (skin), and &lt;1 0 (liver, brain, and muscle) μg/g
Matrix decision procedure to assess new pesticides based on relative groundwater leaching potential and chronic toxicity
Authors: Britt Janice K. , Mcdowell Ted C. , Dwinell Steven E. 
Published: March 2010

Abstract
The high usage of pesticides in the subtropical climate of Florida presents a worst case scenario under which registrations that may impact public health and the environment must be judged A methodology is presented that utilizes chemical environmental fate factors in conjunction with chronic toxicity parameters to better assess new active ingredients that are submitted for registration A ranking index related to leaching potential is assigned to a pesticide as a preliminary screening process If the index falls within a certain numerical range, then a more in depth analysis of the environmental fate and toxicological data for the pesticide occurs A decision matrix that incorporates the results of chronic toxicity analysis and computer simulation of leaching behavior is then applied to the pesticide to decide which registration action may be appropriate This tool has widespread potential for assessing the leaching potential of pesticides to, and the chronic toxicity of pesticides in, ground water
Pesticides in ground water, surface water and spring runoff in a small saskatchewan watershed
Authors: Waite D.T. , Sommerstad H. , Grover R. , Kerr L. , Westcott N.D. 
Published: March 2010

Abstract
The movement of several pesticides was studied from 1985 to 1987 in a small, agricultural watershed The watershed contained a distinct, ephemeral stream bed and two permanent, small reservoirs The five herbicides measured −2,4 dichlorophenoxyacetic acid (2,4 D), dicamba, bromoxynil, diclofop-methyl, and triallate – were those most commonly used in the watershed Of the 105 collected ground water samples 47% contained residues of one or more herbicides Residues in surface water samples were less frequent, and concentrations were lower than those in ground water All spring snowmelt runoff samples were collected in 1985 and 1987 and contained some pesticide residues The significance of these findings will be discussed and related to potential environmental toxicological effects Severe grasshopper infestations in 1985 and 1986 resulted in insecticide treatments in the study area Water samples were tested for the insecticides carbofuran, carbaryl, chlorpyrifos, dimethoate, and deltamethrin Three samples of spring runoff, collected from one site in 1987, contained approximately 1 ppb carbofuran All other samples were less than the detection levels
Biodehalogenation: The metabolism of vinyl chloride byMethylosinus trichosporiumOB-3b. A sequential oxidative and reductive pathway through chloroethylene oxide
Authors: Castro C.E. , Riebeth D.M. , Belser N.O. 
Published: March 2010

AbstractResting cell suspensions of the soil methylotroph Methylosinus trichosporium OB-3b rapidly metabolize vinyl chloride The half-life of the reaction, based on Cl release at pH 7 4, 0 1 in phosphate buffer with a cell density of 0 1 g/ml, is 0 61 h The path of metabolism is complicated but proceeds through the intermediacy of chloroethylene oxide Independent studies of the hydrolysis of this oxirane in water set its chemical half life at 3 9 min The products of its reaction with water are chloroacetaldehyde and hydroxyacetaldehyde They are produced in a ratio of 2 1, as judged by Cl release and 1H and 13C nuclear magnetic resonance analysis Incubations with vinyl chloride 1,2-13C and vinyl chloride 1,2 14C establish that the dominant metabolic pathway entails a quick reduction of chloroethylene oxide to ethylene oxide Ethylene oxide is then converted in sequence to ethylene glycol, hydroxyacetaldehyde, glycolic acid, and CO2 This process is competitive with the chemical hydrolysis of chloroethylene oxide Similarly, chloroacetaldehyde is con verted to chloroacetic acid The latter is only slowly metabolized by this organism, and it accumulates throughout incubation to a final yield of 10% It is concluded that the organism participates in the hydrolysis of both chloroethylene oxide and ethylene oxide
Biodehalogenation: Rapid metabolism of Vinyl Chloride by a soilPseudomonassp. Direct hydrolysis of a vinyl CCl bond
Authors: Castro C.E. , Wade R.S. , Riebeth D.M. , Bartnicki E.W. , Belser N.O. 
Published: March 2010

AbstractResting cell suspensions of a soil Pseudomonas sp readily metabolize vinyl chloride Studies with a combination of 13C and 14C labeled vinyl chloride and metabolites establish that the initial dehalogenation step formally entails a direct hydroxylation of the CCl bond to produce acetaldehyde This substance undergoes biochemical oxidation at both the carbonyl and the methyl carbons to produce acetic acid and hydroxyacetaldehyde These are both further oxidized by the organism to hydroxyacetic acid (glycolic acid), and the latter is converted to carbon dioxide The rate of Cl liberation from vinyl chloride is a function of growth conditions Cells grown on 3 chloropropanol carry out the dehalogenation of vinyl chloride with a t1/2 of 1 3 h at a cell density of 0 1 g/ml
Variability in the performance of the 7-dCeriodaphnia dubiasurvival and reproduction test: An intra- and interlaboratory study
Authors: Degraeve G.M. , Cooney J.D. , Marsh B.H. , Pollock T.L. , Reichenbach N.G. 
Published: March 2010

AbstractThe U.S. Environmental Protection Agency (EPA) has developed a 7-day Ceriodaphnia dubia survival and reproduction test for measuring the toxicity of effluents. This study evaluated the ease of performance and the intra- and interlaboratory variability of this 7-d test, using two reference toxicants (sodium chloride and potassium dichromate), two pulp and paper effluents, and two utility effluents Eleven different laboratories, representing academia, private industry, contractors, and the state EPA and federal EPA, participated in the study. The reference toxicants were tested twice during two separate test periods, and each industrial effluent was tested once. Using the EPA's criteria for a successful test (®80% survival and ® 15 young per female in controls), 56% of the 116 planned tests were completed as valid tests. Most tests were invalid because the laboratories were unable to initiate the tests successfully or because control survival was &lt;80%. Seventy-eight percent of the tests that were initiated were successfully completed. Reproduction no-observed-effect-concentration (NOEC) values were generally somewhat lower than those for survival but had greater variability than survival NOEC values. The interlaboratory variability of the survival (LC50) and reproduction (IC50) results, expressed as the C V., ranged between 29.8 and 30.8% and between 28.9 and 39.0%, respectively. The study demonstrated that about half (56%) of the laboratories participating in the study were able to routinely complete the test successfully. Some of the laboratories experienced with other effluent toxicity tests were less prepared to complete this test successfully. Overall, the variability of the 7-d Ceriodaphnia tests that were completed was similar to the variability observed with other toxicity tests and with analytical chemistry measurements of environmental samples.
Residue-based interpretation of toxicity and bioconcentration QSARs from aquatic bioassays: Neutral narcotic organics
Authors: McCarty L. S. , Dixon D. G. , MacKay D. , Smith A. D. , Ozburn G. W. 
Published: March 2010

AbstractThe critical body residue (CBR), estimated from aquatic toxicity QSARs and bioconcentration-log Kow relationships, appears to be relatively constant, at about 4 mmol L−1 of fish, for the acute toxicity of a variety of hydrophobic narcotic organic chemicals examined by the U.S. Environmental Protection Agency (Duluth, MN) in tests with the fathead minnow. However, for hydrophilic chemicals (log Kow &lt; 1.5) the bulk of the toxicant is in the water phase rather than the organic/lipid phase of the organism, so the whole-body residues in these cases should be similar to the LC50 water concentration. Over the log Kow range of – 1.5 to 6, acutely toxic whole-body residues for narcotics can be approximated by the QSAR-derived equation: CBR (mM) = 2.5 mM + 50/Kow. Estimates obtained by this method are in reasonable agreement with the limited literature data available for acutely toxic whole-body residues of hydrophobic narcotic organic chemicals. Elimination half-lives estimated from nonlinear curve fitting to time-toxicity information were relatively constant for the Duluth bioassay data at approximately 3 h. Despite the relatively high variability of this type of kinetics data, the literature information for small aquatic organisms, from both toxicity-and bioconcentration-based tests, was in a similar range. It appears that QSARs created with raw aquatic bioassay data occur primarily as a result of the influence of chemical-physical properties on the partitioning process. Log Kow appears to have little to do with the inherent potency of the neutral, narcotic organic chemicals examined.
Quantitative analysis of structure-toxicity relationships of substituted anilines by use of Balb/3T3 cells
Authors: Harada Akihisa , Hashimoto Kazuo , Hanzawa Masahiko , Saito Jun 
Published: March 2010

Abstract
The acute toxicities of 24 substituted anilines in terms of 50% inhibition concentrations (150) for viability of cells and their adenosine triphosphate (ATP) content were measured with monolayer cultures of Balb/3T3 cells. The quantitative relationship (QSAR) was analyzed for the pI50 (viability) value with physicochemical substituent parameters. The pI50 (viability) value of substituted anilines was parabolically related with log P, P being the 1-octanol/water partition coefficient, where electronic and hydrogen bonding effects were separately considered. There was a good correspondence between pI50 values for cellular viability and ATP content. None of the test compounds, however, showed any specific depletion of cellular ATP content, suggesting that substituted anilines do not specifically damage the energy metabolism of the cells.
A simple stream-side test system for determining acute lethal and behavioral effects of pesticides on aquatic insects
Authors: Kreutzweiser David P. , Capell Scott S. 
Published: March 2010

Abstract
A stream-side test system was developed to measure direct lethal and behavioral effects of pesticides on stream insects under simulated natural conditions. The system allowed for quantitative analysis of drift response to pesticide exposure (proportion of test species that drifted), drift profile (drift response over time), survival of displaced insects, and survival of test species remaining in the substrate. The design, procedure, analysis, and advantages of this system are presented.
Sublethal effects of cadmium on physiological responses in the pocketbook mussel, Lampsilis ventricosa
Authors: Naimo Teresa J. , Atchison Gary J. , Holland-Bartels Leslie E. 
Published: March 2010

Abstract
Recent studies indicate that the density and diversity of freshwater mussels are declining in many large river systems, possibly from low-level chemical contamination. Exposure of Lam-psilis ventricosa (Barnes, 1823) to 0, 22, 111, and 305 μg/L of cadmium for 28 d in a proportional diluter resulted in a significant decrease (p ≤ 0.05) in respiration rate as cadmium concentration increased. Although variations in cadmium concentrations did not significantly affect food clearance rates or ammonia excretion rates, mussels exposed to 305 μg cadmium per liter showed a decrease in ammonia excretion rates and a decrease in food clearance rates over the 28-d study. Assimilation efficiencies increased during the test in all treatments. Oxygen-to-nitrogen ratios were significantly increased in mussels exposed to either 111 or 305 μg cadmium per liter by day 28. Tissue condition index (TCI) values were significantly lower in mussels in the toxicity test than those in a field sample. The significant change in respiration rate after only a 28-d exposure to cadmium suggests that freshwater mussels may be sensitive indicators of sublethal contaminant exposure. However, the large variability in other physiological responses indicates that the study of contaminant effects requires careful selection of appropriate physiological indicators.
A global perspective on forest decline
Authors: Mueller-Dombois Dieter 
Published: March 2010

Abstract
—,;Carbon dioxide, the major plant food, is on the rise, but forests on both sides of the Atlantic are known to be declining, and industrial pollution is widely suspected to be the principal cause. However, significant contemporary forest declines also are occurring in several Pacific forests, in areas completely unaffected by industrial pollution. This paper focuses on researched forest declines in the Pacific area (New Zealand, Japan, and the Hawaiian and Galápagos islands), where canopy dieback was found to be a natural aspect of forest dynamics. It then summarizes characteristics of forest decline in central Europe (Czechoslovakia and Germany), where decline relates mostly to anthropogenic causes. Commonalities among the natural causes in the Pacific and anthropogenic causes in the European forests are emphasized through recognition of a third factor complex, the demographic component, which so far has been largely neglected in the European forest decline research. The natural cause complexes identified as demographic, disturbance, and biotic components are placed into a causal hierarchy theory based on cohort senescence. It is suggested that this may serve as a framework for comparative ecosystem research of forest declines at the global level, which includes a consideration of ongoing biotic impoverishment and climate change.
Implications of physiological responses to chronic air pollution for forest decline in the southeastern United States
Authors: Richardson Curtis J. , Sasek Thomas W. , Fendick Edward A. 
Published: March 2010

Abstract
The effects of acidic precipitation and ozone on physiological processes in loblolly pine (Pinus taeda L.) were assessed over time to determine dose-response relationships of cumulative exposure to varying levels of ozone and acid rain in combination. Seedlings of known provenance were grown in open-top field chambers in a clear-cut forest site in Duke Forest in the Piedmont of North Carolina and were exposed to pH 5.2 or 3.5 precipitation and several proportional ozone treatments (0.5-3.0x ambient ozone). No direct effects of acid precipitation on gas exchange and carbon fixation were found. Elevated ozone exposures had strong negative effects on needle abscission and net photosynthesis. Exposure-response relationships for photosynthesis indicated that a threshold level of approximately 100 ppm·h of cumulative ozone exposure (12-h summation) had to be reached before significant inhibition occurred. Results suggest that chronic pollutant exposure over the growing season has direct negative effects on carbon fixation in loblolly pine that can significantly reduce long-term growth potential. Current ambient ozone levels in the southeastern United States could be responsible for an approximate 19% reduction in instantaneous carbon fixation rates in loblolly pine by the end of one growing season. An 80 to 90% decrease in net photosynthesis was found at 2.25 and 3.0x ambient ozone concentrations, levels often found in major cities and surrounding areas in the South.