bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluating the ecological significance of laboratory response data to predict population-level effects for the estruarine amphipod Ampelisca abdita
Authors: Kuhn Anne , Munns Wayne R. , Serbst Jonathan , Edwards Phillip , Cantwell Mark G. , Gleason Timothy , Pelletier Marguerite C. , Berry Walter 
Published: March 2010

Abstract
Ten-day acute mortality of the benthic amphipod Ampelisca abdita is used in a number of regulatory, research, and monitoring programs to evaluate chemical contamination of marine sediments. Although this endpoint has proven to be valuable for characterizing the relative toxicities of sediments, the significance of acute mortality with respect to population viability has not yet been established. In this study, population modeling along with empirical extrapolation were used to describe a relationship between acute mortality and population-level response of A. abdita. The research involved the performance of a standard 10-d sediment toxicity bioassay and a 70-d full life-cycle chronic population (including reproduction) bioassay exposing A. abdita to sediments spiked with concentrations of the divalent metal cadmium (normalized to acid volatile sulfide) expected to produce a range of biological effects. These data provided age-specific schedules of survival and fecundity that were used to parameterize an age-classified projection matrix model for A. abdita. Measured exposure data and population growth rate estimates, obtained using the demographic information collected during the 70-d assay, were used to develop exposure—response models. These data were also used to develop an empirical relationship between population growth rate (λ) and acute mortality. This relationship describes how acute data may be used to predict concentrations that produce population-level effects. Model manipulations permit extrapolation of early life-stage mortality (the acute endpoint) to changes in population growth rate. These relationships were used to evaluate a range of ecologically acceptable acute mortality for A. abdita.
Effects of chronic dietary exposure to trace elements on banded water snakes (Nerodia fasciata)
Authors: Hopkins William A. , Roe John H. , Snodgrass Joel W. , Staub Brandon P. , Jackson Brian P. , Congdon Justin D. 
Published: March 2010

Abstract
Little currently is known about the accumulation or effects of contaminants on reptiles. To date, most studies examining reptile exposure to trace elements report tissue burdens of field-captured animals, but seldom provide insight into the dose, duration, or mode of exposure involved. For two years, we fed juvenile banded water snakes (Nerodia fasciata) prey items collected from a coal ash—contaminated site that contained elevated levels of As, Cd, Cu, Se, Sr, and V. With the exception of Cu, snakes accumulated significant concentrations of elements, usually in a dose-dependent manner. Accumulation varied significantly among liver, kidney, and gonads, and in most cases between sexes. Selenium accumulation was most notable, greatly exceeding established toxicity thresholds for other vertebrates. Despite the high concentrations of pollutants accumulated, snakes exposed to the contaminated diet survived through the study and exhibited normal food consumption, growth, condition factor, overwinter survival and mass loss, metabolic rate, and gonadosomatic index. The results of this study confirm that diet can be a significant route of exposure to trace elements in snakes and indicate that further studies on snakes are warranted to better understand their responses to contaminants.
Sexually dimorphic morphology of hatchling snapping turtles (Chelydra serpentina) from contaminated and reference sites in the Great Lakes and St. Lawrence River basin, North America
Authors: de Solla Shane R. , Bishop Christine A. , Brooks Ronald J. 
Published: March 2010

Abstract
Some organochlorine pesticides and industrial chemicals may alter sexually dimorphic traits through endocrine disruption. Therefore, we examined a sexually dimorphic trait, precloacal length, of hatchling snapping turtles (Chelydra serpentina) incubated from 31 clutches from a heavily contaminated site (Hamilton Harbour, ON, Canada; n = 14), a moderately contaminated site (Akwesasne Mohawk Territory; n = 3), and from a reference site (Algonquin Provincial Park, ON, Canada; n = 14). The mean sum polychlorinated biphenyls from Algonquin were low (20.33 ng/g wet wt), but were high from both Hamilton and Akwesasne (2,956.28 and 3,377.0 ng/g wet wt, respectively). Organochlorine pesticides, such as dichlorodiphenyldichloroethylene, were low from Algonquin (1.67 ng/g wet wt), moderate from Akwesasne (10.00 ng/g wet wt), and relatively high from Hamilton (135.14 ng/g wet wt). At all sites, the precloacal length of male hatchlings was larger than that of females by an equal amount at any given body size. However, the precloacal length of both males and females from Hamilton increased with body size at a slower rate than of males and females from the other two sites. Our results support an earlier study that found differences in sexually dimorphic morphology of adult snapping turtles among contaminated and uncontaminated sites. Furthermore, these alterations in secondary sexual characteristics previously observed in adults likely are initiated early in development, and may result in permanent organizational changes in morphology.
A dynamic level IV multimedia environmental model: Application to the fate of polychlorinated biphenyls in the United Kingdom over a 60-year period
Authors: Sweetman Andrew J. , Cousins Ian T. , Seth Rajesh , Jones Kevin C. , Mackay Donald 
Published: March 2010

AbstractA dynamic or level IV multimedia model is described and illustrated by application to the fate of three polychlorinated biphenyl (PCB) congeners in the United Kingdom over a 60-year period from their introduction into commerce until the present. Models of this type are shown to be valuable for elucidating the time response of environmental systems to increasing, decreasing, or pulse inputs. The suggestion is made that in addition to the outputs of time-dependent concentrations (which can be compared with monitoring data for validation purposes), it is useful to examine masses, fugacities, and fugacity ratios between media. The relative importance of processes is best evaluated by compiling cumulative intermedia fluxes and quantities lost by reaction and advection and examining the corresponding process rate constants or their reciprocals, the characteristic times. The suggestion is made that uncertainty and sensitivity analyses are desirable, but it must be appreciated that relative sensitivities of input parameters may change during the simulation period, so a single sensitivity analysis conducted at one point in time can be misleading. The use of the model for forecasting future trends in concentration is illustrated. Given the uncertainties in emission and advective inflow rates, the simulation of PCB fate in the United Kingdom is regarded as showing time trends that are in satisfactory agreement with monitoring data.
Selecting internally consistent physicochemical properties of organic compounds
Authors: Beyer Andreas , Wania Frank , Gouin Todd , Mackay Donald , Matthies Michael 
Published: March 2010

Abstract
Methods are presented for selecting values of chemical properties of vapor pressure, water solubility, Henry's law constant, and octanol—water and octanol—air partition coefficients, which are subject to thermodynamic constraints, while taking advantage of all measurements. The aim of the mathematical procedures is to find the one set of internally consistent partitioning parameters that is minimally divergent from the experimental values. Information about the reliability or uncertainty of reported values can be accounted for by weighing factors. A similar approach is applied to the temperature dependence of these properties. The influence of partial miscibility of the octanol—water system is discussed and a correction is suggested for this effect. The selection method is applied to 50 mostly aromatic chemicals for which multiple measured partitioning data are available. The resulting sets of consistent property data are presented and discussed.
Changes in estrogenic and androgenic activities at different stages of treatment in wastewater treatment works
Authors: Kirk Lucy A. , Tyler Charles R. , Lye Christina M. , Sumpter John P. 
Published: March 2010

AbstractEstrogenic and androgenic activities of wastewater were determined during treatment in five wastewater treatment works (WWTWs) in the Untied Kingdom. With one exception, both estrogenic and androgenic activities decreased markedly as wastewater progressed through the plants; removal rates were generally 70% or higher, sometimes reaching 100%. Most of the reduction in activity occurred during secondary (biological) treatment. In both influents and effluents, estrogenic and androgenic activities were appreciably lower in samples collected in August, when the amount of rain had been substantial, compared with samples collected in April and May. Most final effluents contained very low (or nondetectable) estrogenic activity (undetectable to 13 ng/L of estradiol equivalents) and androgenic activity (undetectable to 143 ng/L of dihydrotestosterone [DHT] equivalents), although one (from a WWTW that had only primary treatment) contained relatively high activities (40 ng/L of estradiol equivalents; 4,033 ng/L of DHT equivalents). The type of treatment available at the various WWTWs also affected the activity of the final effluent. The biological significance of these results will depend upon which chemicals contribute to the estrogenic and androgenic activities, because of widely different potencies of different estrogenic chemicals, and on the degree of dilution of the effluents in their receiving waters.
Oxidation chemistry of acid-volatile sulfide during analysis
Authors: Gonzalez Adrian M. 
Published: March 2010

AbstractThe susceptibility of some components of sediment acid-volatile sulfide (AVS) to chemical oxidation is a critical factor impacting accurate measurement of AVS in sediment samples. This well-documented susceptibility to oxidation led to the requirement for oxygen-free conditions in the analytical method developed for AVS. In light of this acute potential to oxidize, the serendipitous finding that air can be used in the analysis of sediment AVS is counterintuitive and unexpected. To demonstrate and investigate this interesting observation, extraction experiments were performed using aqueous and solid-phase sulfide species. Experiments using air as the carrier gas showed a mean percentage recovery of sulfide matching that of traditional (nitrogen gas) analysis (i.e., &gt;91%) and a time to completion of less than 30 min for aqueous sulfide and less than 60 min for sediment samples. These results are consistent with those of sulfide oxidation studies reported in the literature. Using air as the analytical carrier gas can provide an interesting alternative for developing an analytical method to determine AVS parameters in the field.
Using measured octanol-air partition coefficients to explain environmental partitioning of organochlorine pesticides
Authors: Shoeib Mahiba , Harner Tom 
Published: March 2010

Abstract
Octanol-air partition coefficients (Koa) were measured directly for 19 organochlorine (OC) pesticides over the temperature range of 5 to 35°C. Values of log Koa at 25°C ranged over three orders of magnitude, from 7.4 for hexachlorobenzene to 10.1 for 1,1-dichloro-2,2-bis (p-chlorophenyl) ethane. Measured values were compared to values calculated as KowRT/H (where R is the ideal gas constant [8.314 J mol−1 K−1], T is absolute temperature, and H is Henry's law constant) were, in general, larger. Discrepancies of up to three orders of magnitude were observed, highlighting the need for direct measurements of Koa. Plots of Koa versus inverse absolute temperature exhibited a log-linear correlation. Enthalpies of phase transition between octanol and air (ΔHoa) were determined from the temperature slopes and were in the range of 56 to 105 kJ mol−1 K−1. Activity coefficients in octanol (γo) were determined from Koa and reported supercooled liquid vapor pressures (p oL), and these were in the range of 0.3 to 12, indicating near-ideal solution behavior. Differences in Koa values for structural isomers of hexachlorocyclohexane were also explored. A Koa-based model was described for predicting the partitioning of OC pesticides to aerosols and used to calculate particulate fractions at 25 and −10°C. The model also agreed well with experimental results for several OC pesticides that were equilibrated with urban aerosols in the laboratory. A log-log regression of the particle-gas partition coefficient versus Koa had a slope near unity, indicating that octanol is a good surrogate for the aerosol organic matter.
Identification of polychlorinated dibenzo-p-dioxin, dibenzofuran, and coplanar polychlorinated biphenyl sources in Tokyo Bay, Japan
Authors: Yao Yuan , Masunaga Shigeki , Takada Hideshige , Nakanishi Junko 
Published: March 2010

AbstractA dated sediment core collected from Tokyo Bay, Japan, was used to assess the historical inputs of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (Co-PCBs) from multiple sources. The levels, patterns, and profiles of these compounds in the core were congener-specifically investigated, and the results show that the PCDD and PCDF (PCDD/F) and the Co-PCB inputs increased abruptly from the late 1950s and peaked during the period 1967 to 1972. From 1972 to 1981, the inputs decreased continuously and then generally leveled off. Using principal component analysis, two herbicides widely used in the past, pentachlorophenol (PCP) and chloronitrofen (CNP), as well as combustion processes were identified as the major dioxin sources in Tokyo Bay. The PCB formulations and combustion processes were estimated to be the major sources of Co-PCBs. Furthermore, multiple regression analysis was performed for dioxin-source apportioning, and it was found that the herbicides PCP and CNP have mainly contributed to the PCDD/F burdens since the late 1950s. This study suggests that herbicide-derived PCDD/Fs remaining in agricultural land will continue to run off and pollute the aquatic environment in Japan for a long time.
Precautions in the use of 110mAg as a tracer of silver metabolism in ecotoxicology: Preferential bioconcentration of 109Cd by trout gills after 110mAg exposure
Authors: Hansen Heinz J. M. , Grosell Martin , Jacobsen Ulf , Jørgensen Jesper C. , Hogstrand Christer , Wood Christopher M. 
Published: March 2010

Abstract
An often overlooked problem in the use of radiotracers is the possibility of isotopic contamination. Commercially available silver 110mAg was used to study silver uptake and depuration in rainbow trout and European eel. Quality control by means of comparative γ and β counting brought our attention to a contamination of the 110mAg stock with 109Cd, which could be seen only because the 109Cd was markedly bioconcentrated by trout gills. The contamination could not be detected in eel gills or in other tissues of both species. The difference between trout and eel gill structure and function is the probable explanation for the marked difference in 109Cd accumulation. This contamination was identified as 109Cd by γ spectroscopy and its origin by transmutation of natural silver as a result of neutron activation is described. Failure to recognize this contamination problem would have resulted in serious misinterpretation of the data set. Guidance for avoiding this problem is given.
Immunochemical quantification of metallothioneins in marine mollusks: Characterization of a metal exposure bioindicator
Authors: Boutet Isabelle , Tanguy Arnaud , Auffret Michel , Riso Ricardo , Moraga Dario 
Published: March 2010

Abstract
A recombinant metallothionein CgMT1, from the Pacific oyster Crassostrea gigas, was synthesized and used as antigen in the development of antibodies and a specific enzyme-linked immunosorbent assay (ELISA). The ELISA showed that rabbit anti-CgMT1 IgG reacted with purified CgMT1 and MTs from other marine bivalves, indicating its suitability as a reagent to quantify MTs and for monitoring of metal contamination in field animals. Application of this assay to tissues excised from metal exposed C. gigas showed that MT induction reached a saturation level in gills that was not observed in digestive gland. Quantification of MTs in gills and digestive gland of field-collected C. gigas showed that the MT level depended on the metal concentrations at the collection sites and may have been influenced by salinity variations at estuarine sites. Oysters from metal-contaminated estuarine sites showed lower MT concentrations than those from nonestuarine contaminated sites.
Lysosomal response of earthworm (Eisenia fetida) coelomocytes to the fungicide copper oxychloride and relation to life-cycle parameters
Authors: Reinecke Sophiè A. , Helling Beate , Reinecke Adriaan J. 
Published: March 2010

AbstractJuvenile specimens of the earthworm species Eisenia fetida Savigny, 1826, were exposed in the laboratory to a range of concentrations of the fungicide copper oxychloride. After an eight-week exposure period, the neutral-red retention (NRR) times were measured in the coelomocytes of all the worms that had matured. Life-cycle traits (survival, biomass change, cocoon production, cocoon mass, hatching of cocoons, number of hatchlings) were also monitored. Dose-related effects on NRR times, maturation, growth, and reproduction parameters were determined (one-way analysis of variance, p &lt; 0.05). The lowest effect concentration for substrate copper (Cu) measured for the NRR time was 8.9 mg/kg (dry wt). Growth was severely affected at the highest exposure concentration (330 mg/kg substrate dry wt), at which no worms matured and no NRR times could be measured. Negative linear correlations (p &lt; 0.05) were apparent between the NRR times and substrate and body Cu concentrations. Positive linear relationships were found between the NRR times and some life-cycle parameters (p &lt; 0.05). This study showed that the NRR assay can indicate toxic stress due to Cu exposure at an early stage, and that NRR times can be linked to effects on certain life-cycle traits.
Evaluating best management practices at an urban golf course
Authors: Davis Nate M. , Lydy Michael J. 
Published: March 2010

AbstractThis three-year study evaluated the effects of best management practices (BMPs) in reducing surface water contamination at an urban golf course. Water samples were collected before BMP implementation from two ponds on Braeburn Golf Course (Wichita, KS, USA). The pesticides 2,4-dicholorodiphenoxyacetic acid (2,4-D) and simazine were periodically found at concentrations above recommended water quality criteria. Excessive nutrients in the form of nitrates and total phosphorus were also measured. In addition, an assessment of macroinvertebrate populations revealed only a few tolerant species. Beginning in year 2, recommendations to alter chemical applications on the course were implemented as part of the BMPs. Surface water sampling during year 2 showed significant declines in nitrate and total phosphorus levels; however, seasonal contamination from pesticides continued to occur. Beginning in year 3, structural changes to the golf course were made as part of the BMPs. Subsequent water sampling indicated further reductions of nitrates (80%) and total phosphorus (40 and 60% in the two ponds, respectively), and elimination of contamination from spring applications of 2,4-D and simazine. Finally, an assessment of macroinvertebrate populations indicated an improvement in taxa richness, as well as repopulation by less tolerant organisms. Results of this study can be used to develop and refine golf course management procedures to protect aquatic environments.
The agricultural dispersal-valley drift spray drift modeling system compared with pesticide drift data
Authors: Allwine K. Jerry , Thistle Harold W. , Teske Milton E. , Anhold John 
Published: March 2010

Abstract
The coupling of the valley drift (VALDRIFT) atmospheric dispersion/deposition model with the agricultural dispersal (AGDISP) aircraft wake model generates a modeling system for predicting the off-target drift of pesticides sprayed in a mountain valley. The approach uses the AGDISP near-field spray model to estimate the mass fraction of pesticide remaining airborne after initial application, then the VALDRIFT complex terrain model to estimate the drift of pesticide from the target area. The modeling system inputs include detailed spray information, a measure (or estimate) of winds in the valley, and the valley topographic characteristics; the results are pesticide concentrations throughout the valley atmosphere and pesticide deposition to the valley surface. The AGDISP and VALDRIFT models are operated independently, with the results from AGDISP being used as input to VALDRIFT through user-created data files. The modeling system was evaluated using pesticide drift data from spray trials conducted in the Mill Creek Canyon of Utah's Wasatch Mountains, USA, during the late spring of 1993. The predicted deposition compared within a factor of three of the observations (70% of the time) at all sampling locations extending several kilometers down-valley from the spray treatment block. The overall average ratio of predicted-to-observed deposition was 0.9.
Use of physical, chemical, and biological indices to assess impacts of contaminants and physical habitat alteration in urban streams
Authors: Rogers Catriona E. , Brabander Daniel J. , Barbour Michael T. , Hemond Harold F. 
Published: March 2010

AbstractHuman activities in urban areas can lead to both chemical pollution and physical alteration of stream habitats. The evaluation of ecological impacts on urban streams can be problematic where both types of degradation occur. Effects of contaminants, for example, may be masked if stream channelization, loss of riparian vegetation, or other physical stressors exert comparable or larger influences. In the Aberjona watershed (near Boston, MA, USA), we used physical, chemical, and biological indices to discern the relative impacts of physical and chemical stressors. We used standard protocols for assessing the biological condition of low-gradient streams, sampling macroinvertebrate communities from several different habitat types (e.g., overhanging bank vegetation, undercut bank roots, and vegetation on rocks). We strengthened the linkage between chemical exposure and macroinvertebrate response by measuring metal concentrations not only in sediments from the stream bottom but also in the vegetative habitats where the macroinvertebrates were sampled. Linear regression analysis indicated that biological condition was significantly dependent (95% confidence level) on contaminants in vegetative habitats, but not on contaminants in sediments from the stream bottom. Biological condition was also significantly dependent on physical habitat quality; regression analysis on both contaminants and physical quality yielded the best regression model (r2 = 0.49). Similar biological impairment was observed at sites with severe contamination or physical impairment or with moderate chemical and physical impairment. These results have implications for the management of urban streams.