bluuebunny/crossref_metadata_2025_split huggingface dataset:
Toxicokinetic modeling of mixtures of organic chemicals
Authors: McCarty L. S. , Dixon D. G. , Ozburn G. W. , Smith A. D. 
Published: March 2010

Abstract
A residue-based one-compartment, first-order-kinetics model (1CFOK) was used to investigate the toxicity of mixtures of organic chemicals to the American flagfish, Jordanella floridae. Four sets of chemicals (chloroethanes, chloroethylenes, chlorobenzenes, and chlorophenols) were used to examine within-set mixtures. Component chemicals of the mixtures appeared to be simply additive at threshold LC50. Kinetics rate constants and critical body residue (CBR) data estimated from single chemical toxicity test data, along with bioconcentration factor information calculated from log Kow, were used to model the time course of toxicant action of the mixtures and compare them against independently observed mixture toxicity test results. Agreement between observed and modeled information was good, in terms of both threshold toxicity estimates and the time course of toxicant action.
Historical declines and diebacks of central European forests and present conditions
Authors: Kandler Otto 
Published: March 2010

Abstract
Human activities had reduced the central European forested area to less than 20% by the end of the Middle Ages but increased it again to 30% of the original area during the industrial period. Detailed reports on declines and diebacks have been available since the 18th century. Beginning in the second half of the 19th century, in highly industrialized areas, smoke damage occurred until effective measures were taken to lower SO2 concentrations. Almost complete recolonization of devastated areas by conifers has been observed since the 1960s, with few exceptions, for example, the Ore Mountains in Czechoslovakia. The suggestion that a large-scale decline of European forests (Waldsterben) has taken place since 1979/1980 is not corroborated by 10 years of intensive research. Annual surveys fail to show the expected increase in foliage deficit, a shift from lower to higher damage classes, an increase in mortality, or increasing growth depression in recent decades. No correlation between the spatial and temporal distribution of air pollutants and damage classes has been found. Comparison of old and new photographs and evaluation of old studies on leaf indexes show that similar patterns of crown conditions caused by fluctuating site conditions and diseases have always occurred to a similar extent. Thus, Waldsterben may be understood as a problem of new awareness of old and only partly explained phenomena.
The toxicity of sulfur to microtox® from acetonitrile extracts of contaminated sediments
Authors: Jacobs Mark W. , Delfino Joseph J. , Bitton Gabriel 
Published: March 2010

Abstract
Toxicity bioassays of solvent extracts of sediments are used to evaluate the toxicological effects of extracted hydrophobic organic contaminants. However, this type of bioassay assesses the toxicity of all extracted compounds, natural or anthropogenic. Sediment extracts are typically subjected to cleanup procedures before chemical analysis to remove interfering, coextracted substances. This study evaluated the effect of cleanup procedures on the toxicity of acetonitrile extracts of contaminated sediments by using the Microtox® bioluminescence bioassay. Extract cleanup significantly reduced toxicity of most extracts when copper powder was added to remove coextracted sulfur. Microtox was shown to be highly sensitive (EC50 of 24.7-35.8 μg/L) to elemental sulfur dissolved in several organic solvents. Toxicity tests utilizing solvent extracts of sediments must take into account the toxic effects of coextracted sulfur on bioassay organisms to accurately assess the environmental impacts of extracted hydrophobic contaminants.
Use of three artificial sea salts to maintain fertile sea urchins (arbacia punctulata) and to conduct fertilization tests with copper and sodium dodecyl sulfate
Authors: Neiheisel Timothy W. , Young Melba E. 
Published: March 2010

Abstract
Fertile sea urchins were maintained over six months in three commercial artificial sea-waters (Forty Fathoms®, HW Marinemix®, and Instant Ocean®). Fertilization tests using the reference toxicants copper (Cu) and sodium dodecyl sulfate (SDS) were conducted with the sea urchins in the artificial sea salt in which the organisms were maintained. The ranges of Cu and SDS no-observed-effect concentrations (NOECs) for the tests in the three artificial seawaters overlapped one another and also the ranges of published results for animals maintained and tested in natural sea-water. The 50% effect concentration (EC50) values of Cu for the tests using the three artificial sea-waters were not significantly different. The EC50 value for SDS using HW Marinemix was significantly lower than values for tests using the other artificial seawaters. The artificial seawaters were judged acceptable for maintaining Arbacia punctulata and conducting fertilization tests, although additional research is required to optimize long-term maintenance of fertile animals.
Uptake and accumulation of selenium by terrestrial plants growing on a coal fly ash landfill. Part 3. Forbs and grasses
Authors: Arthur Mary A. , Schneider Robert E. , Weinstein Leonard H. , Rubin Gail 
Published: March 2010

Abstract
Plants grown on coal fly ash landfills can accumulate relatively high concentrations of selenium (Se), which may be ameliorated with gypsum application to the soil. In 1988 and 1989, experiments were conducted to measure the accumulation of Se in forbs and grasses growing on a coal fly ash landfill. In 1990, a dose-response study was conducted to determine whether forbs and grasses growing on a fly ash landfill would respond to gypsum applications with reduced tissue levels of Se and increased levels of S. Higher concentrations of Se were found in plants grown on the landfill than on nonlandfill control plots, and leguminous species tended to accumulate more Se than nonlegumes. Two of the four studied species—bird's-foot trefoil (Lotus corniculatus L.) and bitterweed (Picris hieracioides L.)—had higher concentrations of S when grown with gypsum. However, only bird's-foot trefoil showed significantly reduced Se. The difference in tissue levels of Se and S was a presence/absence response, not a monotonic response to the rate of applied gypsum. Although it is clear that gypsum applications have the potential for mitigating Se uptake by some plants, the response is quite variable on a fly ash landfill, probably due to variability in concentration and availability of Se in the soil cap.
Physiological effects of red phosphorus smoke inhalation on prairie dogs and rock doves
Authors: Johns Brad E. , Thompson R. D. , Crane Kenneth A. 
Published: March 2010

Abstract
Pulmonary function, blood chemistry, and hematology studies were conducted with prairie dogs (Cynomys ludovicianus) and rock doves (Columba livia) under resting conditions to assess environmental risk of exposing wildlife species to multiple applications of red phosphorus/butyl rubber smoke (0.0, 1.0, and 4.0 mg/L). Four daily 80-min smoke exposures had no significant physiological effect on prairie dogs. However, with rock doves, two daily 80-min smoke exposures resulted in elevated respiratory frequency in two males followed by death, a significant concentration × day effect on carbon dioxide production, respiratory exchange ratio, metabolic rate, lymphocytes, and heterophiles, and a significant sex × concentration effect on hemoglobin and methemoglobin. Although results showed that rock doves are more vulnerable to red phosphorus/butyl rubber smoke than prairie dogs, it appears that exposure to the smoke is unlikely to pose a significant risk to either species under field conditions.
Free and conjugated concentrations of nine resin acids in rainbow trout (Oncorhynchus mykiss) following waterborne exposure
Authors: Niimi A. J. , Lee H. B. 
Published: March 2010

Abstract
Rainbow trout (Oncorhynchus mykiss) were exposed to nine resin acids that included abietic, dehydroabietic, chlorodehydroabietic, dichlorodehydroabietic, neoabietic, pimaric, isopimaric, sandaracopimaric, and palustric acids. Bioconcentration factors (BCFs) for these acids ranged from &lt;25 to 130 among fish that were exposed to mean waterborne concentrations of 0.7 to 3.6 μg/L for 20 d. Total free and conjugated acid concentrations ranged from 1 to 3 mg/kg on a wholebody basis. There was a significant relationship (P &lt; 0.01) between decreasing percentage of conjugated/total acid and increasing BCF. Elimination rates were also monitored over a 10-d period, although no detectable levels were observed. Based on initial chemical concentrations, it was concluded that the half-lives of these acids were &lt;4 d.
Extracts from settling particulate matter collected in the Stockholm archipelago waters: Embryolethality, immunotoxicity and erod-inducing potency of fractions containing aliphatics/monoaromatics, diaromatics or polyaromatics
Authors: Veilens Emilie , Brunström Björn , Broman Dag , Näf Carina , Zeböhr Yngve , Dencker Lennart 
Published: March 2010

AbstractBioassays previously used for evaluating the toxic potency of specific compounds as well as mixtures proved useful for testing extracts of environmental samples. Samples of settling seston, that is, settling particulate matter in water, were collected with sediment traps placed in the Stockholm archipelago. The samples were Soxhlet extracted with toluene, the extracts run through an Si column, and the eluates separated by HPLC into (a) aliphatics and monoaromatics, (b) diaromatics (e.g., polychlorinated dibenzo-p-dioxins [PCDDs] and dibenzofurans [PCDFs] and polychlorinated biphenyls [PCBs]), and (c) polyaromatics. Toxic potency was evaluated in terms of mortality in chick embryos, induction of 7-ethoxyresorufin-O-deethylase (EROD) in chick embryos, inhibition of lymphoid development in chick embryo bursae, and inhibition of lymphoid development in mouse thymus anlagen in vitro. The polyaromatic fraction from seston collected at a location (inner archipelago) close to the center of Stockholm was the most potent of the tested fractions. The polyaromatic fractions were analyzed to determine their contents of 15 polycyclic aromatic hydrocarbons (PAHs) that had previously been toxicity tested. The concentrations of these PAHs were too low to explain the toxicities of the polyaromatic fractions. The diaromatic fraction from the inner archipelago was about four- to fivefold less potent as an EROD inducer and at inhibiting lymphoid development in mouse thymus anlagen in vitro, compared with the polyaromatic fraction from this location. Analysis of PCDD/Fs and three coplanar PCBs in this diaromatic fraction revealed that these compounds were responsible only for a minor part of the toxicity of the fraction.
Toxicity of endosulfan to native and introduced fish in Australia
Authors: Sunderam R. I. M. , Thompson G. B. , Cheng D. M. H. 
Published: March 2010

AbstractSemistatic bioassays of endosulfan with native and introduced Australian fish indicated that they are sensitive to this insecticide at low concentrations. The introduced European carp (Cyprinus carpio) was the most sensitive species, with a measured 96-h LC50 of 0.1 μg/L, whereas the native eastern rainbow fish (Melanotaenia duboulayi) and silver perch (Bidyanus bidyanus) were the least sensitive, with measured 96-h LC50 values of 2.4μg/L. The measured 96-h LC50 values of endosulfan for bony bream (Nematolosa erebi), golden perch (Macquaria ambigua), and rainbow trout (Oncorhynchus mykiss) were 0.2, 0.5, and 1.6 μ/L, respectively. Toxicities of endosulfan in Sydney mains water and Mehi River water were similar when rainbow fish, golden perch, and silver perch were used as test animals. The initial measured concentration was about 42% of the nominal concentration, whereas final measured concentration after 24 h in semistatic tests declined to 5.6% of the nominal concentration. The toxicity of endosulfan was similar in Australian native and introduced fish and in overseas fish, but varied markedly with test method. The 96-h LC50 values for one species, the rainbow fish, varied from 0.5μg/L when reported as measured concentrations in a flow-through test to 11.4 μg/L as nominal values in a static test. These differences span much of the variation found in 96-h LC50 values for all fish species described in the world literature.
Granular insecticides and birds: Factors to be considered in understanding exposure and reducing risk
Authors: Best Louis B. , Fischer David L. 
Published: March 2010

Abstract
Granular insecticides are used extensively, and many are highly toxic to birds. Here we discuss potential routes of avian exposure to granular insecticides and factors influencing those routes, suggest possible corrective measures for reducing exposure, and identify areas of needed research. Potential routes of exposure include inhalation or dermal absorption, inadvertent ingestion of granules, ingestion of prey or plant material containing pesticide residues, mistaking granules for food, and consuming granules as a source of grit. Bird consumption of granules for grit depends on factors affecting availability, bird behavior, grit/granule characteristics preferred by birds, and grit/granule retention in the gizzard. Avian exposure to granular insecticides may be reduced by taking into account factors such as application rate/incorporation of granules, habitat-use patterns of birds, granule integrity in the field, rate of release of insecticide from the granules, and consumption of granules as a source of grit or food. Altering certain physical characteristics of insecticide granules may reduce avian exposure; these include granule size, shape and surface texture, composition, color, and insecticide load. Research needs include evaluations of the U.S. Environmental Protection Agency's current granular risk index, the relative importance of the various potential routes of exposure, grit-use patterns of birds, and bird habitat use and behavior in treated fields.
The biological significance of contaminants in sediment from hamilton harbour, Lake Ontario
Authors: Krantzberg Gail , Boyd Duncan 
Published: March 2010

Abstract
Sediment from regions within Hamilton Harbour is highly contaminated with metals and polyaromatic hydrocarbons (PAHs); nevertheless, macroinvertebrates are present in situ and not all contaminated sites were toxic to laboratory organisms. Most sediment did elicit sublethal and/or lethal responses in bioassay species. Results of analyses of tissue residues in bioassay organisms, and the amelioration of toxicity by chemical treatments, implicate trace metals as contributing to sediment toxicity. Sediment oxygen demand, however, apparently contributed to the restricted benthic community in situ and some of the toxicity observed in vitro. In addition, for some stations there was evidence that PAHs were responsible for the detected deleterious effects. The study concluded that the suitability for colonization by benthic invertebrates of sediment in some areas of Hamilton Harbour is apparently limited both by contaminants and by high sediment oxygen demand. Remedial options aimed at eliminating oxygen depletion of the bottom waters of the harbor should result in improvements in the benthic invertebrate community directly, by providing a suitable oxygen regime for organisms less tolerant of temporal anoxia, and indirectly, by decreasing metal bioavailability, possibly through the coprecipitation of trace metals with iron hydroxides. The use of chemical treatments in sediment bioassays provides a technique for evaluating the source of sediment-associated toxicity.
Relationships between physiological and fish population responses in a contaminated stream
Authors: Adams S. Marshall , Crumby W. Dennis , Greeley Mark S. , Ryon Michael G. , Schilling Elizabeth M. 
Published: March 2010

Abstract
Relationships between toxicant exposure, physiological effects, and population-level responses were investigated in redbreast sunfish (Lepomis auritus) from a stream receiving chronic inputs of mixed contaminants. Elevated levels of detoxification enzymes, which provided evidence of direct toxicant exposure, were associated with low lipid levels, histopathological damage, and reduced growth for fish at the upper three sites in the contaminated stream. Decreased fecundity, exhibited by fish at the upper site, might have been due to the reduced capacity of the liver to manufacture yolk proteins. Reduction in lipid pools due to metabolic drains might have decreased the amount of physiological useful energy needed for growth resulting in smaller age-specific sizes of fish at the upper three sites. This approach for investigating relationships between contaminant exposure, physiological effects, and population-level responses such as growth and size distributions could serve as a model for designing biomonitoring studies and for stimulating further research to improve our ability to evaluate the ecological significance of chronic contaminant stressors on aquatic ecosystems.
Biodegradation of acrylonitrile in soil
Authors: Donbero Phyllis A. , Odelson David A. , Klecka Gary M. , Markham Daniel A. 
Published: March 2010

Abstract
The aerobic biodegradation of [14Clacrylonitrile at concentrations ranging from 10 to 1,000 ppm was examined in a variety of surface soils. At concentrations up to 100 ppm, complete degradation of the compound occurred in &lt;2 d in a Londo soil. Greater than 50% of the radioactivity was recovered as [14C]carbon dioxide following 6 d of incubation. Because the soil had no known previous exposure to acrylonitrile, dissimilation did not appear to require acclimation of the microorganisms. Transient formation of acrylamide and acrylic acid as intermediates of degradation was also observed. These results appear to be consistent with previously published results of acrylonitrile transformation by axenic microbial cultures. Similar results were obtained in studies conducted with Tappan loam (10, 50, 100 ppm) and sand (10 and 50 ppm). Acclimation of the microorganisms was required before degradation of 100 ppm acrylonitrile in sand. Degradation of higher concentrations (500 and 1,000 ppm in Londo soil) was relatively slow and may be due to inhibitory effects of the parent compound.
Competition potentials of environmentally applied bacteria with human fecal microbiota
Authors: Nelson Gail M. , Claxton L. D. , Creason J. P. , George S. E. 
Published: March 2010

Abstract
One of the potential human health effects associated with the environmental release of microorganisms is colonization of the intestinal tract. This study uses serial transfer techniques to monitor the in vitro survival and competition with human fecal microbiota of Pseudomonas aeruginosa strains BC16 and AC869. Strain BC16 was isolated from a commercial product for polychlorinated biphenyl (PCB) degradation, and AC869 is a 3,5–dichlorobenzoate degrader. In addition, a mouse intestinal isolate, Pseudomonas aeruginosa strain PAMG, was studied as a positive control. Results were compared to previously published mouse fecal microbiota studies. Quantitative comparison of the fecal microbiota populations enumerated on selective media found human and mouse cultures to be nearly identical. Survival of the competitor strains was also similar in both the human and the mouse systems. By culture 5 of the human serial transfer experiments, strains AC869 and PAMG were present at significantly higher levels than strain BC16. In previous serial transfer experiments with mouse fecal flora, strain AC869 was present at a higher level than strains PAMG and BC16 by culture 5. No alterations of the microbiota populations due to the addition of a competitor strain were found. This system can be helpful in identifying environmental strains with a high potential for colonizing the intestinal tract.
Effects of bleached kraft mill effluent on fish in the St. Maurice River, Quebec
Authors: Hodson Peter V. , Thivierge Denis , Levesque Marie-Claude , McWhirter Michelle , Ralph Karen , Gray Bruce , Whittle D. Michael , Carey John H. , Van Der Kraak Glen 
Published: March 2010

Abstract
Tissue levels of chlorinated dioxins and furans and the physiological and biochemical responses of fish were measured upstream and downstream of a bleached kraft mill in the St. Maurice River, Quebec. Relative to fish 10 km upstream of the source, white suckers (Catostomus commersoni) downstream showed evidence of chemical exposure, chemical metabolism, stress, and altered energy use. Levels of 2,3,7,8–tetrachlorodibenzo-p-dioxin and tetrachlorodibenzofuran in gutted whole fish averaged 23 and 260 pg/g immediately downstream of the plant and declined to 18 and 112 pg/g at 95 km downstream. The activity of hepatic aryl hydrocarbon hydroxylase (AHH) was 10X higher immediately downstream and 5X higher 95 km downstream. There were corresponding increases in relative liver size, hematocrit, serum glucose, serum protein, and fin-ray asymmetries, with a pattern of response that matched enzyme induction. These responses pointed to a strong effluent effect and followed the patterns of tissue contamination by dioxins and furans and of water contamination by chlorinated phenolics and guaiacols. There were strong correlations between AHH induction and tissue contamination. Whereas lipid levels increased at all downstream sites, condition factor decreased at 95 km from the source, indicating that there may be disturbances in energy metabolism. Effects on sexual maturation, as shown by levels of serum hormones and gonad somatic index, were inconclusive.
Distribution and metabolism of polycyclic aromatic hydrocarbons (PAHs) injected into eggs of chicken (Gallus domesticus) and common eider duck (Somateria mollissima)
Authors: Näf Carina , Broman Dag , Brunström Björn 
Published: March 2010

Abstract
The present study focuses on the uptake, distribution, and metabolism of 16 polycyclic aromatic hydrocarbons (PAHs) injected into eggs of chicken (Gallus domesticus) and common eider (Somateria mollissima). Of the total dose of 0.2 ppm, injected on day 4 of incubation, 94% was metabolized within the chicken egg by day 18. The gallbladder showed the highest PAH concentrations of the analyzed organs/structures (gallbladder, liver, kidney, adipose tissue) of the chick and eider embryos. The proportion of the total PAH content present in these organs/structures was higher in the eider embryo (40%) than in the chick embryo (16%). Chick embryos, eider embryos, and wild juvenile eiders had similar PAH concentrations and PAH profiles. The characteristics of this “PAH pool” seemed to be largely unrelated to the relative concentrations of the PAHs to which the birds were exposed, the age of the organisms, and the routes of exposure. The largest studied PAH molecule, coronene, was not taken up from the yolk by the embryo as efficiently as the other PAHs, but once taken up it was metabolized as readily as the others. Basal aryl hydrocarbon (benzo[apyrene) hydroxylase (AHH) activities of chick and eider embryos were of similar magnitude.