WorldWideScience

Sample records for environmental fate properties

  1. Predicting the environmental fate properties of petroleum hydrocarbon mixtures

    International Nuclear Information System (INIS)

    Pisigan, R.A. Jr.; Tucker, W.A.

    1995-01-01

    The environmental fate and transport of petroleum products for risk assessment can be evaluated based on the physico-chemical properties of an indicator chemical or a surrogate compound, or the whole mixture. A study was conducted to develop a simple representation of the hydrocarbon mixture as if it contained only few constituents, each of which represents a large number of compounds. The products considered are gasoline, diesel fuel, and jet fuel (JP4). Each petroleum hydrocarbon was characterized as a mixture of six constituents: short chain alkanes, long chain alkanes, short chain cycloalkanes and alkenes, long chain cycloalkanes and alkenes, BTEX, and other aromatics. The carbon number used as a cut-off between short and long chain alkanes, alkenes, and cycloalkanes varies with the type of product. Each mixture has different average molecular weight, water solubility, vapor pressure, organic carbon partition coefficient, and air diffusivity. The properties of each constituent of gasoline were derived from the weighted average of all compounds belonging to each constituent group. For diesel fuel and JP4, the properties of each constituent were generated from the properties of the component most representative of the group. Any property that is missing or not available from common literature sources was derived from regression equations developed from the data base for gasoline. These regression equations express the property as function of the number of carbon atoms. The R 2 values of the regression equations range from 0.82--0.92. Some case studies involving petroleum product contamination in which the estimated properties were applied are presented

  2. OPERA models for predicting physicochemical properties and environmental fate endpoints.

    Science.gov (United States)

    Mansouri, Kamel; Grulke, Chris M; Judson, Richard S; Williams, Antony J

    2018-03-08

    The collection of chemical structure information and associated experimental data for quantitative structure-activity/property relationship (QSAR/QSPR) modeling is facilitated by an increasing number of public databases containing large amounts of useful data. However, the performance of QSAR models highly depends on the quality of the data and modeling methodology used. This study aims to develop robust QSAR/QSPR models for chemical properties of environmental interest that can be used for regulatory purposes. This study primarily uses data from the publicly available PHYSPROP database consisting of a set of 13 common physicochemical and environmental fate properties. These datasets have undergone extensive curation using an automated workflow to select only high-quality data, and the chemical structures were standardized prior to calculation of the molecular descriptors. The modeling procedure was developed based on the five Organization for Economic Cooperation and Development (OECD) principles for QSAR models. A weighted k-nearest neighbor approach was adopted using a minimum number of required descriptors calculated using PaDEL, an open-source software. The genetic algorithms selected only the most pertinent and mechanistically interpretable descriptors (2-15, with an average of 11 descriptors). The sizes of the modeled datasets varied from 150 chemicals for biodegradability half-life to 14,050 chemicals for logP, with an average of 3222 chemicals across all endpoints. The optimal models were built on randomly selected training sets (75%) and validated using fivefold cross-validation (CV) and test sets (25%). The CV Q 2 of the models varied from 0.72 to 0.95, with an average of 0.86 and an R 2 test value from 0.71 to 0.96, with an average of 0.82. Modeling and performance details are described in QSAR model reporting format and were validated by the European Commission's Joint Research Center to be OECD compliant. All models are freely available as an open

  3. Environmental properties of long chain alcohols. Part 1: Physicochemical, environmental fate and acute aquatic toxicity properties

    DEFF Research Database (Denmark)

    Fisk, Peter; Sanderson, Hans; Wildey, Ross

    2009-01-01

    )SARs). This allows predictions of data relating to human and environmental safety profiles and patterns. These alcohols have been shown to be rapidly degradable under standard conditions up to C18. Furthermore, evidence suggests that longer chain lengths are also rapidly biodegradable. While log Kow values suggest......This paper summarises the physicochemical, biodegradation and acute aquatic ecotoxicity properties of long chain aliphatic alcohols. Properties of pure compounds are shown to follow somewhat predictable trends, which are amenable to estimation by quantitative structure-activity relationships ((Q...

  4. Environmental properties of long chain alcohols. Part 1: Physicochemical, environmental fate and acute aquatic toxicity properties

    DEFF Research Database (Denmark)

    Fisk, Peter; Sanderson, Hans; Wildey, Ross

    2009-01-01

    )SARs). This allows predictions of data relating to human and environmental safety profiles and patterns. These alcohols have been shown to be rapidly degradable under standard conditions up to C18. Furthermore, evidence suggests that longer chain lengths are also rapidly biodegradable. While log Kow values suggest...

  5. Investigating the Toxicity and Environmental Fate of Graphene Nanomaterials

    Science.gov (United States)

    The Hersam Laboratory at Northwestern University works with the Center for Environmental Implications of Nanotechnology and the United States Environmental Protection Agency to study the toxicity and environmental fate of emergent nanomaterials, specifically carbon-based nanomate...

  6. Fate and transport of fragrance materials in principal environmental sinks.

    Science.gov (United States)

    Zhang, Xiaolei; Brar, Satinder Kaur; Yan, Song; Tyagi, Rajeshwar Dayal; Surampalli, Rao Y

    2013-10-01

    Fragrance materials are widely present in the environment, such as air, water, and soil. Concerns have been raised due to the increasing utilization and suspected impact on human health. The bioaccumulating property is considered as one of the causes of the toxicity to human beings. The removal of fragrance materials from environmental sinks has not been paid enough attention due to the lack of regulation and research on their toxicity. This paper provides systematic information on how fragrance materials are transferred to the environment, how do they affect human lives, and what is their fate in water, wastewater, wastewater sludge, and soil. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Environmental fate of tungsten from military use

    International Nuclear Information System (INIS)

    Clausen, Jay L.; Korte, Nic

    2009-01-01

    This manuscript describes the distribution, fate and transport of tungsten used in training rounds at three small arms ranges at Camp Edwards on the Massachusetts Military Reservation (MMR), USA. Practice with tungsten/nylon rounds began in 2000 subsequent to a 1997 US Environmental Protection Agency ban on training with lead. Training with the tungsten rounds was halted in 2005 because of concerns regarding tungsten's environmental mobility and potential toxicity. This study, therefore, examines how tungsten partitions in the environment when fired on a small arms training range. Soil sampling revealed surface soil concentrations, highest at the berm face, up to 2080 mg/kg. Concentrations decreased rapidly with depth-at least by an order of magnitude by 25 cm. Nonetheless, tungsten concentrations remained above background to at least 150 cm. Pore-water samples from lysimeters installed in berm areas revealed a range of concentrations (< 1-400 mg/L) elevated with respect to background although there was no discernable trend with depth. Groundwater monitoring well samples collected approximately 30 m below ground surface showed tungsten (0.001-0.56 mg/L) attributable to range use

  8. Environmental fate of tungsten from military use

    Energy Technology Data Exchange (ETDEWEB)

    Clausen, Jay L. [Research and Development Center, Cold Regions Research and Engineering Laboratory, 72 Lyme Road, Hanover, New Hampshire, 03755 (United States)], E-mail: Jay.L.Clausen@erdc.usace.army.mil; Korte, Nic [1946 Clover Ct., Grand Junction, Colorado, 81506 (United States)

    2009-04-01

    This manuscript describes the distribution, fate and transport of tungsten used in training rounds at three small arms ranges at Camp Edwards on the Massachusetts Military Reservation (MMR), USA. Practice with tungsten/nylon rounds began in 2000 subsequent to a 1997 US Environmental Protection Agency ban on training with lead. Training with the tungsten rounds was halted in 2005 because of concerns regarding tungsten's environmental mobility and potential toxicity. This study, therefore, examines how tungsten partitions in the environment when fired on a small arms training range. Soil sampling revealed surface soil concentrations, highest at the berm face, up to 2080 mg/kg. Concentrations decreased rapidly with depth-at least by an order of magnitude by 25 cm. Nonetheless, tungsten concentrations remained above background to at least 150 cm. Pore-water samples from lysimeters installed in berm areas revealed a range of concentrations (< 1-400 mg/L) elevated with respect to background although there was no discernable trend with depth. Groundwater monitoring well samples collected approximately 30 m below ground surface showed tungsten (0.001-0.56 mg/L) attributable to range use.

  9. Environmental fate and behaviour of nanomaterials

    DEFF Research Database (Denmark)

    Hartmann, Nanna Isabella Bloch; Skjolding, Lars Michael; Hansen, Steffen Foss

    In the current report, the existing knowledge on the fate of nanomaterials in the environment is reviewed and the major knowledge gaps are identified.......In the current report, the existing knowledge on the fate of nanomaterials in the environment is reviewed and the major knowledge gaps are identified....

  10. 40 CFR 158.1300 - Environmental fate data requirements table.

    Science.gov (United States)

    2010-07-01

    ... transformation products. 7. Environmental chemistry methods used to generate data associated with this study must... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Environmental fate data requirements table. 158.1300 Section 158.1300 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED...

  11. Environmental fate of pesticides applied on coffee crops in ...

    African Journals Online (AJOL)

    The aim of this paper was evaluate the environmental fate of pesticides applied in coffee crops in southeast of Brazil, using the level I fugacity model. Chemical and physical characteristics of the pesticides were considered in different environmental compartments and applied fugacity equations. The preliminary evaluation ...

  12. The environmental release and fate of antibiotics.

    Science.gov (United States)

    Manzetti, Sergio; Ghisi, Rossella

    2014-02-15

    Antibiotics have been used as medical remedies for over 50 years and have recently emerged as new pollutants in the environment. This review encompasses the fate of several antibiotics in the environment, including sulfonamides, nitrofurans, terfenadines, cephalosporins and cyclosporins. It investigates the cycle of transfer from humans and animals including their metabolic transformation. The results show that antibiotic metabolites are of considerable persistence and are localized to ground-water and drinking water supplies. Furthermore, the results also show that several phases of the cycle of antibiotics in the environment are not well understood, such as how low concentrations of antibiotic metabolites in the diet affect humans and animals. This review also shows that improved wastewater decontamination processes are remediating factors for these emerging pollutants. The results obtained here may help legislators and authorities in understanding the fate and transformation of antibiotics in the environment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Surface Immobilization of Engineered Nanomaterials for in Situ Study of their Environmental Transformations and Fate

    Science.gov (United States)

    The transformation and environmental fate of engineered nanomaterials (ENMs) is the focus of intense research due to concerns about their potential impacts in the environment as a result of their uniquely engineered properties. Many approaches are being applied to investigate th...

  14. Challenges in assessing the environmental fate and exposure of nano silver

    International Nuclear Information System (INIS)

    Whiteley, Cherrie M; Jones, Kevin C; Sweetman, Andy J; Dalla Valle, Matteo

    2011-01-01

    There are significant challenges in assessing the fate and exposure of nano particles (NPs) owing to the lack of information on their use and potential pathways and sinks in the environment. This paper discusses these issues using nanosilver as a case study. The approach taken is to assess the production of nanosilver, the range of products that utilise its properties, potential environmental release pathways and subsequent fate. Estimates of UK nanosilver released into the environment have been made and sewage sludge identified as an important receiving compartment. This work aims to highlight the on-going challenges faced when assessing NPs in the environment. Using nanosilver as an example, difficulties in assessing production, use and release are discussed. The study also recommends a potential approach to assess the fate and behaviour assessment of nanosilver in the environment.

  15. Environmental fate of rice paddy pesticides in a model ecosystem.

    Science.gov (United States)

    Tomizawa, C; Kazano, H

    1979-01-01

    The distribution and metabolic fate of several rice paddy pesticides were evaluated in a modified model ecosystem. Among the three BHC isomers, beta-isomer was the most stable and bioconcentrated in all of the organisms. Alpha- and gamma-isomers were moderately persistent and degraded to some extent during the 33 day period. Disulfoton was relatively persistent due to the transformation to its oxidation products. Pyridaphenthion was fairly biodegradable. N-Phenyl maleic hydrazide derived from the hydrolysis of pyridaphenthion was not detected in the organisms though it was found in the aquarium water after 33 days. Cartap and edifenphos were considerably biodegradable, and the ratio of the conversion to water soluble metabolites was very high. There was a distinct difference in the persistence of Kitazin P and edifenphos in the aquarium water. It appeared that the hydrolysis rate of the pesticides affected their fate in the organisms. PCP appeared to be moderately biodegradable. CNP was considerably stable and stored in the organisms though the concentration in the aquarium water was relatively low. The persistence and distribution of the pesticides in the model ecosystem were dependent on their chemical structures. In spite of the limitation derived from short experimental period, the model ecosystem may be applicable for predicting the environmental fate of pesticides.

  16. Regulatory relevant and reliable methods and data for determining the environmental fate of manufactured nanomaterials

    DEFF Research Database (Denmark)

    Baun, Anders; Sayre, Phil; Steinhäuser, Klaus Günter

    2017-01-01

    The widespread use of manufactured nanomaterials (MN) increases the need for describing and predicting their environmental fate and behaviour. A number of recent reviews have addressed the scientific challenges in disclosing the governing processes for the environmental fate and behaviour of MNs,...... data. Gaps do however exist in test methods for environmental fate, such as methods to estimate heteroagglomeration and the tendency for MNs to transform in the environment.......The widespread use of manufactured nanomaterials (MN) increases the need for describing and predicting their environmental fate and behaviour. A number of recent reviews have addressed the scientific challenges in disclosing the governing processes for the environmental fate and behaviour of MNs......, however there has been less focus on the regulatory adequacy of the data available for MN. The aim of this paper is therefore to review data, testing protocols and guidance papers which describe the environmental fate and behaviour of MN with a focus on their regulatory reliability and relevance. Given...

  17. Fate of triazoles in softwood upon environmental exposure.

    Science.gov (United States)

    Kukowski, Klara; Martinská, Veronika; Sedgeman, Carl A; Kuplic, Paige; Kozliak, Evguenii I; Fisher, Stephen; Kubátová, Alena

    2017-10-01

    Determining the fate of preservatives in commercial wood products is essential to minimize their losses and improve protective impregnation techniques. The fate of triazole fungicides in ponderosa pine wood was investigated in both outdoor and controlled-environment experiments using a representative triazole, tebuconazole (TAZ), which was accompanied by propiconazole (PAZ) in selected experiments. The study was designed to mimic industrial settings used in window frame manufacturing. To investigate the TAZ fate in detail, loosely and strongly bound fractions were differentiated using a multi-step extraction. The loosely bound TAZ fraction extracted through two sonications accounted for 85± 5% of the total TAZ, while the strongly bound TAZ was extracted only with an exhaustive Soxhlet extraction and corresponded to the remaining 15± 5%. A significant fraction (∼80%) of the original TAZ remained in the wood despite a six-month exposure to harsh environmental conditions, maintaining wood preservation and assuring minimal environmental impact. Depletion of loosely bound TAZ was observed from cross-sectional surfaces when exposed to rain, high humidity and sunlight. Water leaching was deemed to be the major route leading to triazole losses from wood. Leaching rate was found to be slightly higher for TAZ than for PAZ. The contribution of bio-, photo- and thermal degradation of triazoles was negligible as both PAZ and TAZ sorbed in wood remained intact. Triazole evaporation was also found to be minor at the moderate temperature (20-25 °C) recorded throughout the outdoor study. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. [Environmental behavior of graphene and its effect on the transport and fate of pollutants in environment].

    Science.gov (United States)

    Ren, Wen-Jie; Teng, Ying

    2014-09-01

    Graphene is one of the most popular research topics in carbon nanomaterials. Because of its special physical and chemical properties, graphene will have wide applications. As the production and application amount is increasing, graphene will be inevitably released to the environment, resulting in risks of ecological environment and human health. It is of very vital significance for evaluating environmental risks of graphene scientifically and objectively to understand its environmental behavior and fate and explore its effect on the environmental behaviors of pollutants. This paper reviewed the environmental behavior of graphene, such as colloid properties and its stability in the aqueous environment and its transport through porous media. Additionally, the paper reviewed the effect of graphene on the transport and fate of pollutants. The interactions between graphene and heavy metals or organic compounds were especially discussed. Important topics should be explored including sorption mechanisms, interactions between graphene and soil components, influence of graphene on the transport and bioavailability of pollutants in environment, as well as approaches to quantifying graphene. The review might identify potential new ideas for further research in applications of graphene.

  19. Environmental fate and transport of chemical signatures from buried landmines -- Screening model formulation and initial simulations

    Energy Technology Data Exchange (ETDEWEB)

    Phelan, J.M.; Webb, S.W.

    1997-06-01

    The fate and transport of chemical signature molecules that emanate from buried landmines is strongly influenced by physical chemical properties and by environmental conditions of the specific chemical compounds. Published data have been evaluated as the input parameters that are used in the simulation of the fate and transport processes. A one-dimensional model developed for screening agricultural pesticides was modified and used to simulate the appearance of a surface flux above a buried landmine, estimate the subsurface total concentration, and show the phase specific concentrations at the ground surface. The physical chemical properties of TNT cause a majority of the mass released to the soil system to be bound to the solid phase soil particles. The majority of the transport occurs in the liquid phase with diffusion and evaporation driven advection of soil water as the primary mechanisms for the flux to the ground surface. The simulations provided herein should only be used for initial conceptual designs of chemical pre-concentration subsystems or complete detection systems. The physical processes modeled required necessary simplifying assumptions to allow for analytical solutions. Emerging numerical simulation tools will soon be available that should provide more realistic estimates that can be used to predict the success of landmine chemical detection surveys based on knowledge of the chemical and soil properties, and environmental conditions where the mines are buried. Additional measurements of the chemical properties in soils are also needed before a fully predictive approach can be confidently applied.

  20. A review of the environmental corrosion, fate and bioavailability of munitions grade depleted uranium

    Energy Technology Data Exchange (ETDEWEB)

    Handley-Sidhu, Stephanie, E-mail: s.handley-sidhu@bham.ac.uk [Water Sciences Research Group, School of Geography, Earth, Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Keith-Roach, Miranda J. [Biogeochemistry and Environmental Analytical Chemistry Research Group, and School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Lloyd, Jonathan R.; Vaughan, David J. [Williamson Research Centre for Molecular Environmental Science, and School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Manchester M13 9PL (United Kingdom)

    2010-11-01

    Depleted uranium (DU) is a by-product of nuclear fuel enrichment and is used in antitank penetrators due to its high density, self-sharpening, and pyrophoric properties. Military activities have left a legacy of DU waste in terrestrial and marine environments, and there have been only limited attempts to clean up affected environments. Ten years ago, very little information was available on the dispersion of DU as penetrators hit their targets or the fate of DU penetrators left behind in environmental systems. However, the marked increase in research since then has improved our knowledge of the environmental impact of firing DU and the factors that control the corrosion of DU and its subsequent migration through the environment. In this paper, the literature is reviewed and consolidated to provide a detailed overview of the current understanding of the environmental behaviour of DU and to highlight areas that need further consideration.

  1. Environmental fate and exposure models: advances and challenges in 21st century chemical risk assessment.

    Science.gov (United States)

    Di Guardo, Antonio; Gouin, Todd; MacLeod, Matthew; Scheringer, Martin

    2018-01-24

    Environmental fate and exposure models are a powerful means to integrate information on chemicals, their partitioning and degradation behaviour, the environmental scenario and the emissions in order to compile a picture of chemical distribution and fluxes in the multimedia environment. A 1995 pioneering book, resulting from a series of workshops among model developers and users, reported the main advantages and identified needs for research in the field of multimedia fate models. Considerable efforts were devoted to their improvement in the past 25 years and many aspects were refined; notably the inclusion of nanomaterials among the modelled substances, the development of models at different spatial and temporal scales, the estimation of chemical properties and emission data, the incorporation of additional environmental media and processes, the integration of sensitivity and uncertainty analysis in the simulations. However, some challenging issues remain and require research efforts and attention: the need of methods to estimate partition coefficients for polar and ionizable chemical in the environment, a better description of bioavailability in different environments as well as the requirement of injecting more ecological realism in exposure predictions to account for the diversity of ecosystem structures and functions in risk assessment. Finally, to transfer new scientific developments into the realm of regulatory risk assessment, we propose the formation of expert groups that compare, discuss and recommend model modifications and updates and help develop practical tools for risk assessment.

  2. Assessment of the Environmental Fate of the Herbicides Flufenacet and Metazachlor with the SWAT Model.

    Science.gov (United States)

    Fohrer, Nicola; Dietrich, Antje; Kolychalow, Olga; Ulrich, Uta

    2014-01-01

    This study aims to assess the environmental fate of the commonly used herbicides flufenacet and metazachlor in the Northern German Lowlands with the ecohydrological Soil and Water Assessment Tool (SWAT model) and to test the sensitivity of pesticide-related input parameters on the modeled transport dynamics. The river discharge of the Kielstau watershed was calibrated (Nash-Sutcliffe efficiency [NSE], 0.83; = 0.84) and validated (NSE, 0.76; = 0.77) for a daily time step. The environmental fate of metazachlor (NSE, 0.68; = 0.62) and flufenacet (NSE, 0.13; = 0.51) was simulated adequately. In comparison to metazachlor, the simulated flufenacet concentration and loads show a lower model efficiency due to the weaker simulation of the stream flow. The in-stream herbicide loads were less than 0.01% of the applied amount in the observed time period and thus not in conflict with European Environmental Legislation. The sensitivity analysis showed that, besides the accurate simulation of stream flow, the parameterization of the temporal and spatial distribution of the herbicide application throughout the watershed is the key factor for appropriate modeling results, whereas the physicochemical properties of the pesticides play a minor role in the modeling process. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  3. Environmental fate of TCDD and Agent Orange and bioavailability to troops in Vietnam

    Energy Technology Data Exchange (ETDEWEB)

    Karch, N.J.; Watkins, D.K.; Ginevan, M.E. [Exponent, Inc., Washington, DC (United States); Young, A.L. [Oklahoma Univ., Norman, OK (United States)

    2004-09-15

    This paper reviews the environmental fate of Agent Orange and the contaminant, 2,3,7,8- tetrachlorodibenzo-p-dioxin (TCDD), and discusses how this affects the bioavailability of TCDD for ground troops in Vietnam.

  4. Environmental Behavior and Fate of Explosives in Groundwater from the Milan Army Ammunition Plant in Aquatic and Wetland Plants. Fate of TNT and RDX

    National Research Council Canada - National Science Library

    Best, Elly

    1998-01-01

    The present study was performed to elucidate the environmental behavior and fate of TNT and RDX in aquatic and wetland plants collected from a field-scale wetland demonstration deployed at Milan Army...

  5. Prediction of the Fate of Organic Compounds in the Environment From Their Molecular Properties: A Review.

    Science.gov (United States)

    Mamy, Laure; Patureau, Dominique; Barriuso, Enrique; Bedos, Carole; Bessac, Fabienne; Louchart, Xavier; Martin-Laurent, Fabrice; Miege, Cecile; Benoit, Pierre

    2015-06-18

    A comprehensive review of quantitative structure-activity relationships (QSAR) allowing the prediction of the fate of organic compounds in the environment from their molecular properties was done. The considered processes were water dissolution, dissociation, volatilization, retention on soils and sediments (mainly adsorption and desorption), degradation (biotic and abiotic), and absorption by plants. A total of 790 equations involving 686 structural molecular descriptors are reported to estimate 90 environmental parameters related to these processes. A significant number of equations was found for dissociation process (pK a ), water dissolution or hydrophobic behavior (especially through the K OW parameter), adsorption to soils and biodegradation. A lack of QSAR was observed to estimate desorption or potential of transfer to water. Among the 686 molecular descriptors, five were found to be dominant in the 790 collected equations and the most generic ones: four quantum-chemical descriptors, the energy of the highest occupied molecular orbital (E HOMO ) and the energy of the lowest unoccupied molecular orbital (E LUMO ), polarizability (α) and dipole moment (μ), and one constitutional descriptor, the molecular weight. Keeping in mind that the combination of descriptors belonging to different categories (constitutional, topological, quantum-chemical) led to improve QSAR performances, these descriptors should be considered for the development of new QSAR, for further predictions of environmental parameters. This review also allows finding of the relevant QSAR equations to predict the fate of a wide diversity of compounds in the environment.

  6. 40 CFR 158.2150 - Microbial pesticides nontarget organisms and environmental fate data requirements table.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Microbial pesticides nontarget... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2150 Microbial pesticides nontarget organisms and environmental fate data...

  7. Addressing the complexity of water chemistry in environmental fate modeling for engineered nanoparticles.

    Science.gov (United States)

    Sani-Kast, Nicole; Scheringer, Martin; Slomberg, Danielle; Labille, Jérôme; Praetorius, Antonia; Ollivier, Patrick; Hungerbühler, Konrad

    2015-12-01

    Engineered nanoparticle (ENP) fate models developed to date - aimed at predicting ENP concentration in the aqueous environment - have limited applicability because they employ constant environmental conditions along the modeled system or a highly specific environmental representation; both approaches do not show the effects of spatial and/or temporal variability. To address this conceptual gap, we developed a novel modeling strategy that: 1) incorporates spatial variability in environmental conditions in an existing ENP fate model; and 2) analyzes the effect of a wide range of randomly sampled environmental conditions (representing variations in water chemistry). This approach was employed to investigate the transport of nano-TiO2 in the Lower Rhône River (France) under numerous sets of environmental conditions. The predicted spatial concentration profiles of nano-TiO2 were then grouped according to their similarity by using cluster analysis. The analysis resulted in a small number of clusters representing groups of spatial concentration profiles. All clusters show nano-TiO2 accumulation in the sediment layer, supporting results from previous studies. Analysis of the characteristic features of each cluster demonstrated a strong association between the water conditions in regions close to the ENP emission source and the cluster membership of the corresponding spatial concentration profiles. In particular, water compositions favoring heteroaggregation between the ENPs and suspended particulate matter resulted in clusters of low variability. These conditions are, therefore, reliable predictors of the eventual fate of the modeled ENPs. The conclusions from this study are also valid for ENP fate in other large river systems. Our results, therefore, shift the focus of future modeling and experimental research of ENP environmental fate to the water characteristic in regions near the expected ENP emission sources. Under conditions favoring heteroaggregation in these

  8. Environmental Application, Fate, Effects, and Concerns of Ionic Liquids: A Review.

    Science.gov (United States)

    Amde, Meseret; Liu, Jing-Fu; Pang, Long

    2015-11-03

    Ionic liquids (ILs) comprise mostly of organic salts with negligible vapor pressure and low flammability that are proposed as replacements for volatile solvents. ILs have been promoted as "green" solvents and widely investigated for their various applications. Although the utility of these chemicals is unquestionable, their toxic effects have attracted great attention. In order to manage their potential hazards and design environmentally benign ILs, understanding their environmental behavior, fate and effects is important. In this review, environmentally relevant issues of ILs, including their environmental application, environmental behavior and toxicity are addressed. In addition, also presented are the influence of ILs on the environmental fate and toxicity of other coexisting contaminants, important routes for designing nontoxic ILs and the techniques that might be adopted for the removal of ILs.

  9. Environmental fate of natural radioactive contaminants in fertilizers and phosphogypsum

    International Nuclear Information System (INIS)

    Batalha, Marcia Salamoni; Genuchten, Martinus Theodorus van

    2010-01-01

    Agricultural soils often require the use of fertilizers and soil conditioners for optimal production. Phosphate fertilizers produced from igneous phosphate rock often contain small amounts of natural radionuclides (notably uranium and thorium), while the byproduct phosphogypsum (dihydrated calcium sulfate) is typically enriched in radium and lead. It is important to understand the long-term fate of these radionuclides when routinely applied via fertilizers ( 238 U and 234 U) and phosphogypsum as an amendment ( 226 Ra and 210 Pb) to agricultural lands. This study addresses the results of modeling their transport in a typical Cerrado soil profile. The HYDRUS-1D code was used to compare possible soil and groundwater pollution scenarios following the long term use of fertilizers and phosphogypsum in agricultural operations. Results using the equilibrium transport approach suggest that radionuclide concentrations originating from the use of phosphate fertilizers and phosphogypsum are relatively modest and will not pose a major risk to polluting underlying groundwater resources. (author)

  10. Environmental fate of natural radioactive contaminants in fertilizers and phosphogypsum

    Energy Technology Data Exchange (ETDEWEB)

    Batalha, Marcia Salamoni; Genuchten, Martinus Theodorus van, E-mail: msbatalha@oi.com.b, E-mail: rvangenuchten@yahoo.co [Federal University of Rio de Janeiro (LTTC/COPPE/UFRJ), RJ (Brazil). Dept. of Mechanical Engineering. Lab. de Transmissao e Tecnologia do Calor; Bezerra, Camila Rosa, E-mail: camila.rosabz@gmail.co [Federal University of Rio de Janeiro (COPPE/UFRJ), RJ (Brazil). Dept. of Civil Engineering; Pontedeiro, Elizabeth May, E-mail: bettymay@cnen.gov.b [Brazilian Nuclear Energy Commission (CNEN), Rio de Janeiro, RJ (Brazil)

    2010-07-01

    Agricultural soils often require the use of fertilizers and soil conditioners for optimal production. Phosphate fertilizers produced from igneous phosphate rock often contain small amounts of natural radionuclides (notably uranium and thorium), while the byproduct phosphogypsum (dihydrated calcium sulfate) is typically enriched in radium and lead. It is important to understand the long-term fate of these radionuclides when routinely applied via fertilizers ({sup 238}U and {sup 234}U) and phosphogypsum as an amendment ({sup 226}Ra and {sup 210}Pb) to agricultural lands. This study addresses the results of modeling their transport in a typical Cerrado soil profile. The HYDRUS-1D code was used to compare possible soil and groundwater pollution scenarios following the long term use of fertilizers and phosphogypsum in agricultural operations. Results using the equilibrium transport approach suggest that radionuclide concentrations originating from the use of phosphate fertilizers and phosphogypsum are relatively modest and will not pose a major risk to polluting underlying groundwater resources. (author)

  11. Environmental Fate and Analysis of Ptaquiloside from the Bracken Fern

    DEFF Research Database (Denmark)

    Clauson-Kaas, Frederik

    The naturally occurring phytotoxin ptaquiloside (PTA) has long been known to be both acute toxic and carcinogenic. Contents of more than 1% ptaquiloside on dry weight has been detected in bracken (Pteridium spp.), a fern distributed across the globe in often dense populations. This work focused...... on the fate of PTA in the soil-water system, from where it may leach to drinking water sources. PTA was detected in concentrations up to 2.2 µg/L in natural waters receiving drainage from bracken populations, and was found in both surface and groundwater. It was shown that ptaquiloside leached off bracken...... fronds (the leaves of ferns) in concentrations up to 169 µ/L during rainfall events. Rainfall further determined the concentration in a stream that drained a bracken-covered catchment, suggesting that this is a potent driver of ptaquiloside exposure in the environment. In both pure and natural waters, p...

  12. Illustrating sensitivity in environmental fate models using partitioning maps - application to selected contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, T.; Wania, F. [Univ. of Toronto at Scarborough - DPES, Toronto (Canada)

    2004-09-15

    Generic environmental multimedia fate models are important tools in the assessment of the impact of organic pollutants. Because of limited possibilities to evaluate generic models by comparison with measured data and the increasing regulatory use of such models, uncertainties of model input and output are of considerable concern. This led to a demand for sensitivity and uncertainty analyses for the outputs of environmental fate models. Usually, variations of model predictions of the environmental fate of organic contaminants are analyzed for only one or at most a few selected chemicals, even though parameter sensitivity and contribution to uncertainty are widely different for different chemicals. We recently presented a graphical method that allows for the comprehensive investigation of model sensitivity and uncertainty for all neutral organic chemicals simultaneously. This is achieved by defining a two-dimensional hypothetical ''chemical space'' as a function of the equilibrium partition coefficients between air, water, and octanol (K{sub OW}, K{sub AW}, K{sub OA}), and plotting sensitivity and/or uncertainty of a specific model result to each input parameter as function of this chemical space. Here we show how such sensitivity maps can be used to quickly identify the variables with the highest influence on the environmental fate of selected, chlorobenzenes, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), hexachlorocyclohexanes (HCHs) and brominated flame retardents (BFRs).

  13. Model ecosystem determination of the metabolic and environmental fate of tetrachloro-DDT

    International Nuclear Information System (INIS)

    Cole, R.B.; Metcalf, R.L.

    1987-01-01

    A potential hazardous waste site investigation was conducted by the Environmental Protection Agency to determine whether ground water, surface water, or area soils and sediments were contaminated as a result of waster water discharges or improper solid waste disposal practices of a pesticide manufacturer. One of the compounds discharged into the environment was 1,1,1,2-tetrachloro-2,2-bis(p-chlorophenyl)ethane, commonly referred to as tetrachloro-DDT. Unlike a great many of the DDT analogs, tetrachloro-DDT has come under only limited scrutiny, mainly because it was dismissed as having poor insecticidal properties relative to DDT and other analogs. Its metabolism in ingesting organisms, and degradative pathways in the environment have consequently been left uncertain. This model ecosystem study was undertaken to examine the unanswered questions concerning the metabolic and environmental fate of tetrachloro-DDT. The relevance of this study pertains to disposal practices of pesticide manufacturers who use tetrachloro-DDT as a product precursor

  14. Climate-based archetypes for the environmental fate assessment of chemicals.

    Science.gov (United States)

    Ciuffo, Biagio; Sala, Serenella

    2013-11-15

    Emissions of chemicals have been on the rise for years, and their impacts are greatly influenced by spatial differentiation. Chemicals are usually emitted locally but their impact can be felt both locally and globally, due to their chemical properties and persistence. The variability of environmental parameters in the emission compartment may affect the chemicals' fate and the exposure at different orders of magnitude. The assessment of the environmental fate of chemicals and the inherent spatial differentiation requires the use of multimedia models at various levels of complexity (from a simple box model to complex computational and high-spatial-resolution models). The objective of these models is to support ecological and human health risk assessment, by reducing the uncertainty of chemical impact assessments. The parameterisation of spatially resolved multimedia models is usually based on scenarios of evaluative environments, or on geographical resolutions related to administrative boundaries (e.g. countries/continents) or landscape areas (e.g. watersheds, eco-regions). The choice of the most appropriate scale and scenario is important from a management perspective, as a balance should be reached between a simplified approach and computationally intensive multimedia models. In this paper, which aims to go beyond the more traditional approach based on scale/resolution (cell, country, and basin), we propose and assess climate-based archetypes for the impact assessment of chemicals released in air. We define the archetypes based on the main drivers of spatial variability, which we systematically identify by adopting global sensitivity analysis techniques. A case study that uses the high resolution multimedia model MAPPE (Multimedia Assessment of Pollutant Pathways in the Environment) is presented. Results of the analysis showed that suitable archetypes should be both climate- and chemical-specific, as different chemicals (or groups of them) have different traits

  15. Sources and fate of environmental radioactivity at the earth's surface

    International Nuclear Information System (INIS)

    El-Daoushy, F.

    2010-01-01

    Sources and fate of environmental radioactivity at the earth surface This is to link environmental radioactivity to RP in Africa? To describe the benefits of Africa from this field in terms of RP, safety and security policies. To create a mission and a vision to fulfil the needs of ONE PEOPLE, ONE GOAL, ONE FAITH. Sources, processes and fate of environmental radioactivity Previous experience helps setting up an African agenda.(1) Factors influencing cosmogenic radionuclides(2) Factors influencing artificial radionuclides: (a) nuclear weapon-tests (b) nuclear accidents (c) Energy, mining and industrial waste (3) Factors influencing the global Rn-222 and its daughters. (4) Dynamics of cycles of natural radioactivity, e.g. Pb-210. (5) Environmental radiotracers act as DIAGNOSTIC TOOLS to assess air and water quality and impacts of the atmospheric and hydrospheric compartments on ecosystems.6) Definition of base-lines for rehabilitation and protection. Climate influences sources/behaviour/fate of environmental radioactivity. Impacts on life forms in Africa would be severe. Assessing environmental radioactivity resolves these issue

  16. Monitoring fate and behaviour of Nanoceria under relevant environmental conditions

    CSIR Research Space (South Africa)

    Tancu, Y

    2014-11-01

    Full Text Available ). The results revealed significant tendency of nCeO¬2 to undergo aggregation, agglomeration and certain degree of deagglomeration processes under different environmental conditions. Moreover, the findings suggested that both electrostatic and steric interactions...

  17. Study of the photodegradation of a fragrance ingredient for aquatic environmental fate assessment.

    Science.gov (United States)

    Lin, Jianming; Emberger, Matthew

    2017-04-01

    Photodegradation is an important abiotic degradation process to be taken into account for more accurate assessment of the fate of chemicals in the aquatic environment, especially those that are not readily biodegradable. Although the significant role of indirect photodegradation in the environmental fate of chemicals has been revealed in recent research, because of the many confounding factors affecting its kinetics, no straightforward approaches can be used to investigate this degradation process for environmental fate assessment. The indirect photodegradation of a fragrance ingredient named Pamplewood was studied in this work for its fate assessment. Indirect photodegradation rates under various indoor and outdoor conditions were measured by using an LC-MS method. Although the half-lives varied from 4 to 13 days, they collectively indicated that Pamplewood is intrinsically photolabile and can undergo rapid photodegradation. Results from quencher experiments revealed that ⋅OH was the main reactive intermediate responsible for indirect photodegradation, with a half-life of about 18 days in sunlit surface water, based on the experimentally determined second-order rate constant (8.48 ± 0.19 × 10 9  M -1  s -1 ). Photodegradation products of Pamplewood were also studied by GC-MS, LC-MS and total organic carbon content analyses. The results indicated that intermediates of Pamplewood photodegradation continued to photodegrade into smaller and more polar species. Complete mineralization of Pamplewood was observed when it was reacted with hydroxyl radicals in an aqueous solution. This novel approach can be applied for a more realistic environmental fate assessment of other non-readily biodegradable, hydrolysis-resistant, and non-sunlight-absorbing fragrance ingredients. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Evaluating the Environmental Fate of Short-Chain Chlorinated Paraffins (SCCPs) in the Nordic Environment Using a Dynamic Multimedia Model

    OpenAIRE

    Krogseth, Ingjerd Sunde; Breivik, Knut; Arnot, Jon A; Wania, Frank; Borgen, Anders; Schlabach, Martin

    2013-01-01

    Short chain chlorinated paraffins (SCCPs) raise concerns due to their potential for persistence, bioaccumulation, long-range transport and adverse effects. An understanding of their environmental fate remains limited, partly due to the complexity of the mixture. The purpose of this study was to evaluate whether a mechanistic, integrated, dynamic environmental fate and bioaccumulation multimedia model (CoZMoMAN) can reconcile what is known about environmental emissions and human exposure of SC...

  19. Aquatic Environmental Contamination: The fate of Asejire Lake in ...

    African Journals Online (AJOL)

    titi_aladesanmi

    In Nigeria major cities face serious water pollution crises, in which lack of environmental control of ... stocks are at the upper end of the food chains and are vital food supplies to local ... massive fish kills and loss of aquatic life and habitats in.

  20. Aqueous chemistry of chlorine: chemistry, analysis, and environmental fate of reactive oxidant species

    Energy Technology Data Exchange (ETDEWEB)

    Jolley, R.L.; Carpenter, J.H.

    1982-01-01

    This report reviews (1) the chemistry of chlorine relative to its reactions in fresh, estuarine, and marine waters and the formation of reactive oxidant species; (2) the current status of chemical analysis of reactive chlorine species and chlorine-produced oxidant species relative to analysis of low concentrations (microgram-per-liter range) and determination of accuracy and precision of methods; and (3) the environmental fate of chlorine and chlorine-produced oxidant species.

  1. Environmental Fate and Effects of Organotin Biocides: A Molecular and Microbiological Assessment.

    Science.gov (United States)

    1986-12-12

    and effects of the toxic tributyltin species, an active agent in new ship antifouling coatings. -44-4eiped- vltratrace’butyltin measurement’ ehdl c d...environments. However, the environmental occurrence, fate and effects of the highly toxic tributyltin species leached from the paints was virtually unexplored...biodegradation of tributyltin species; and 4) provided novel molecular topological correlations between molecular geometry and toxicity of organotin

  2. Environmental fate and effects of nicotine released during cigarette production.

    Science.gov (United States)

    Seckar, Joel A; Stavanja, Mari S; Harp, Paul R; Yi, Yongsheng; Garner, Charles D; Doi, Jon

    2008-07-01

    A variety of test methods were used to study the gradation, bioaccumulation, and toxicity of nicotine. Studies included determination of the octanol-water partition coefficient, conversion to CO2 in soil and activated sludge, and evaluation of the effects on microbiological and algal inhibition as well as plant germination and root elongation. The partitioning of nicotine between octanol and water indicated that nicotine will not bioaccumulate regardless of the pH of the medium. The aqueous and soil-based biodegradation studies indicated that nicotine is readily biodegradable in both types of media. The microbiological inhibition and aquatic and terrestrial toxicity tests indicated that nicotine has low toxicity. The U.S. Environmental Protection Agency Persistence, Bioaccumulation, and Toxicity Profiler model, based on the structure of nicotine and the predictive rates of hydroxyl radical and ozone reactions, estimated an atmospheric half-life of less than 5.0 h. Using this value in the Canadian Environmental Modeling Center level III model, the half-life of nicotine was estimated as 3.0 d in water and 0.5 d in soil. This model also estimated nicotine discharge into the environment; nicotine would be expected to be found predominantly in water (93%), followed by soil (4%), air (3%), and sediment (0.4%). Using the estimated nicotine concentrations in water, soil, and sediment and the proper median effective concentrations derived from the algal growth, biomass inhibition, and buttercrunch lettuce (Lactuca sativa) seed germination and root elongation studies, hazard quotients of between 10(-7) and 10(-8) were calculated, providing further support for the conclusion that the potential for nicotine toxicity to aquatic and terrestrial species in the environment is extremely low.

  3. Controls on the Environmental Fate of Compounds Controlled by Coupled Hydrologic and Reactive Processes

    Science.gov (United States)

    Hixson, J.; Ward, A. S.; McConville, M.; Remucal, C.

    2017-12-01

    Current understanding of how compounds interact with hydrologic processes or reactive processes have been well established. However, the environmental fate for compounds that interact with hydrologic AND reactive processes is not well known, yet critical in evaluating environmental risk. Evaluations of risk are often simplified to homogenize processes in space and time and to assess processes independently of one another. However, we know spatial heterogeneity and time-variable reactivities complicate predictions of environmental transport and fate, and is further complicated by the interaction of these processes, limiting our ability to accurately predict risk. Compounds that interact with both systems, such as photolytic compounds, require that both components are fully understood in order to predict transport and fate. Release of photolytic compounds occurs through both unintentional releases and intentional loadings. Evaluating risks associated with unintentional releases and implementing best management practices for intentional releases requires an in-depth understanding of the sensitivity of photolytic compounds to external controls. Lampricides, such as 3-trifluoromethyl-4-nitrophenol (TFM), are broadly applied in the Great Lakes system to control the population of invasive sea lamprey. Over-dosing can yield fish kills and other detrimental impacts. Still, planning accounts for time of passage and dilution, but not the interaction of the physical and chemical systems (i.e., storage in the hyporheic zone and time-variable decay rates). In this study, we model a series of TFM applications to test the efficacy of dosing as a function of system characteristics. Overall, our results demonstrate the complexity associated with photo-sensitive compounds through stream-hyporheic systems, and highlight the need to better understand how physical and chemical systems interact to control transport and fate in the environment.

  4. Assessment of the environmental fate of cycloxaprid in flooded and anaerobic soils by radioisotopic tracing

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xuanqi; Xu, Xiaoyong; Li, Chao [Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China, University of Science and Technology, Shanghai 200237 (China); Zhang, Hanxue; Fu, Qiuguo [Institute of Nuclear Agricultural Sciences, Zhejiang University, Hangzhou 310029 (China); Shao, Xusheng [Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China, University of Science and Technology, Shanghai 200237 (China); Ye, Qingfu, E-mail: qfye@zju.edu.cn [Institute of Nuclear Agricultural Sciences, Zhejiang University, Hangzhou 310029 (China); Li, Zhong, E-mail: lizhong@ecust.edu.cn [Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China, University of Science and Technology, Shanghai 200237 (China)

    2016-02-01

    Cycloxaprid (CYC) is a novel broad-spectrum neonicotinoid insecticide that has been developed for agricultural pest control. The fate of the {sup 14}C-labeled racemic and enantio-pure CYC isomers in flooded and anaerobic soil was investigated using radioisotope tracing techniques. After 100 d of incubation, only a minor portion (< 1%) of the applied CYC isomers is mineralized by each of the four tested soil types. The fraction of initially applied radioactive CYC dissipated into the bound or non-extractable residues (BR) increases with increase in the length of the incubation period, reaching up to 53.0–81.6%. The dissipation of the CYC through mineralization or formation of BR is strongly influenced by soil properties, such as humic content, pH value, and retained microbial activity. Amongst the soils studied, the fluvio-marine yellow loamy soil displayed the highest tendency to mineralize CYC while the coastal saline soil exhibited the strongest tendency to form BR. The observation that the water phase retained the large portion(> 60%) of the radioactivity attributed to the total extractable residue suggested that under the experimental condition, the initially applied {sup 14}C-labeled CYC residues were readily available for leaching or offsite transport. Additionally, no enantiomer-specific behaviors are observed. The results from this study provide a framework for assessing the environmental impact resulting from the use of this pesticide. - Highlights: • Only a minor portion (<1%) of the applied CYC was mineralized. • The bound residue increased over time, reaching up to 53.0-81.6%. • CYC residues were readily available for leaching. • No enantiomer-specific behaviors were observed.

  5. Human population intake fractions and environmental fate factors of toxic pollutants in life cycle impact assessment

    NARCIS (Netherlands)

    Huijbregts, M.A.J.; Struijs, Jaap; Goedkoop, Mark; Heijungs, Reinout; Jan Hendriks, A.; Van De Meent, Dik

    2005-01-01

    The present paper outlines an update of the fate and exposure part of the fate, exposure and effects model USES-LCA. The new fate and exposure module of USES-LCA was applied to calculate human population intake fractions and fate factors of the freshwater, marine and terrestrial environment for 3393

  6. Biomaterial property-controlled stem cell fates for cardiac regeneration

    Directory of Open Access Journals (Sweden)

    Yanyi Xu

    2016-09-01

    Full Text Available Myocardial infarction (MI affects more than 8 million people in the United States alone. Due to the insufficient regeneration capacity of the native myocardium, one widely studied approach is cardiac tissue engineering, in which cells are delivered with or without biomaterials and/or regulatory factors to fully regenerate the cardiac functions. Specifically, in vitro cardiac tissue engineering focuses on using biomaterials as a reservoir for cells to attach, as well as a carrier of various regulatory factors such as growth factors and peptides, providing high cell retention and a proper microenvironment for cells to migrate, grow and differentiate within the scaffolds before implantation. Many studies have shown that the full establishment of a functional cardiac tissue in vitro requires synergistic actions between the seeded cells, the tissue culture condition, and the biochemical and biophysical environment provided by the biomaterials-based scaffolds. Proper electrical stimulation and mechanical stretch during the in vitro culture can induce the ordered orientation and differentiation of the seeded cells. On the other hand, the various scaffolds biochemical and biophysical properties such as polymer composition, ligand concentration, biodegradability, scaffold topography and mechanical properties can also have a significant effect on the cellular processes.

  7. A review of ecological effects and environmental fate of illicit drugs in aquatic ecosystems.

    Science.gov (United States)

    Rosi-Marshall, E J; Snow, D; Bartelt-Hunt, S L; Paspalof, A; Tank, J L

    2015-01-23

    Although illicit drugs are detected in surface waters throughout the world, their environmental fate and ecological effects are not well understood. Many illicit drugs and their breakdown products have been detected in surface waters and temporal and spatial variability in use translates into "hot spots and hot moments" of occurrence. Illicit drug occurrence in regions of production and use and areas with insufficient wastewater treatment are not well studied and should be targeted for further study. Evidence suggests that illicit drugs may not be persistent, as their half-lives are relatively short, but may exhibit "pseudo-persistence" wherein continual use results in persistent occurrence. We reviewed the literature on the ecological effects of these compounds on aquatic organisms and although research is limited, a wide array of aquatic organisms, including bacteria, algae, invertebrates, and fishes, have receptors that make them potentially sensitive to these compounds. In summary, illicit drugs occur in surface waters and aquatic organisms may be affected by these compounds; research is needed that focuses on concentrations of illicit drugs in areas of production and high use, environmental fate of these compounds, and effects of these compounds on aquatic ecosystems at the concentrations that typically occur in the environment. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. An evaluation of the environmental fate and behavior of munitions materiel (Tetryl and polar metabolites of TNT) in soil and plant systems. Environmental fate and behavior of tetryl

    Energy Technology Data Exchange (ETDEWEB)

    Fellows, R.J.; Harvey, S.D.; Cataldo, D.A.

    1993-09-01

    The objective of the present studies was to elucidate the environmental behavior and fate of 2,4,6trintrophenylmethylnitramine (tetryl) in the soil/plant system in three different types of soils incubated for 60 days. No tetryl was detectable after 11 days; most of the radiolabel was associated with non-extractable soil components and four transformation products appeared rapidly, of which two were identified as N-methyl-2,4,6-trintroaniline and N-methyl-aminodinitroaniline isomer. Short-term hydroponic studies indicated no significant difference in uptake rates for the three plant species employed. Kinetic studies indicated that plants have a high affinity and capacity for absorbing tetryl. Partitioning patterns indicated that the root is the major accumulation site for tetryl. Chemical fractionation and analyses of tissues showed rapid metabolism of tetryl in tissues of all species, which proceeded toward more polar metabolic products. Plant maturity studies indicated significant differences in the total relative uptake of tetryl by all three plant species based on soil type.

  9. Effects of pH upon the environmental fate of [14C]fenitrothion in an aquatic microcosm

    International Nuclear Information System (INIS)

    Fisher, S.W.

    1985-01-01

    The environmental fate of [ 14 C]fenitrothion was evaluated in aquatic microcosms held at pH 8.3 or 6.7. No general effect attributable to pH was observed; however, several significant interactions were identified. Of these, the findings that statistically higher amounts of radioactivity were present in water held at pH 6.7 and that significantly less metabolism of the parent compound occurred in the organisms at pH 8.3 were preeminent. These differences seen in metabolism and environmental fate between pH values are relatively minor and do not compromise the safety of the compound

  10. Environmental indicators for evaluating properties

    Directory of Open Access Journals (Sweden)

    Mario Grosso

    2015-06-01

    Full Text Available Property evaluation for tax purposes has traditionally relied on urban and building criteria, mostly resulting from concepts driven by the commercial attractiveness of the property under evaluation, its building and the site itself. Due to the world climate and ecological crisis, awareness has risen about the need for other indicators, which can evaluate the quality of a property, even referring to its potential environmental impact. Technical standards for the evaluation of buildings’ environmental sustainability, which have been developed since the first years of this century, both nationally and internationally, take into account the impact of the building and its relevance for the life-cycle of materials and elements, with reference to the three sectors of sustainability: environmental, economic and social. The social sector includes indicators referring to the user’s health and comfort, which also interact with the morphological and spatial characteristics of the building. However, there is a lack of methodological tools for the evaluation of said indicators and existing ones are mainly of a qualitative type. This paper suggests a methodological approach for the quantitative evaluation of sustainability indicators, relying on the accessibility of a site’s climate resources by the property, as a criterion to evaluate the potential for the reduction of negative environmental impact, as well as a criterion to improve users’ life quality.

  11. Effects of nanoplastics and microplastics on toxicity, bioaccumulation, and environmental fate of phenanthrene in fresh water.

    Science.gov (United States)

    Ma, Yini; Huang, Anna; Cao, Siqi; Sun, Feifei; Wang, Lianhong; Guo, Hongyan; Ji, Rong

    2016-12-01

    Contamination of fine plastic particles (FPs), including micrometer to millimeter plastics (MPs) and nanometer plastics (NPs), in the environment has caught great concerns. FPs are strong adsorbents for hydrophobic toxic pollutants and may affect their fate and toxicity in the environment; however, such information is still rare. We studied joint toxicity of FPs with phenanthrene to Daphnia magna and effects of FPs on the environmental fate and bioaccumulation of 14 C-phenanthrene in fresh water. Within the five sizes particles we tested (from 50 nm to 10 μm), 50-nm NPs showed significant toxicity and physical damage to D. magna. The joint toxicity of 50-nm NPs and phenanthrene to D. magna showed an additive effect. During a 14-days incubation, the presence of NPs significantly enhanced bioaccumulation of phenanthrene-derived residues in daphnid body and inhibited the dissipation and transformation of phenanthrene in the medium, while 10-μm MPs did not show significant effects on the bioaccumulation, dissipation, and transformation of phenanthrene. The differences may be attributed to higher adsorption of phenanthrene on 50-nm NPs than 10-μm MPs. Our findings underlined the high potential ecological risks of FPs, and suggested that NPs should be given more concerns, in terms of their interaction with hydrophobic pollutants in the environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. The environmental fate of polybrominated diphenyl ethers in the centre of Stockholm - Assessment using a multimedia fugacity model

    Energy Technology Data Exchange (ETDEWEB)

    Palm, Anna

    2001-01-01

    A local-scale assessment of the environmental fate of three congeners of polybrominated diphenyl ethers (PBDEs) has been performed for the centre of Stockholm. The partitioning properties and main transport processes of these congeners in Stockholm are identified using a site-specific multimedia fugacity model, called CeStoc, that was developed and parameterized for the area of interest. CeStoc was based on level III and IV fugacity models. Five compartments were included: air, water, soil, sediment and an organic film covering the impervious surfaces in the city. The model was satisfactory calibrated with the PAH fluoranthene, before it was run for the compounds of interest. Validation with environmental levels of PBDEs was made where possible, showing reasonable agreement with model results. According to the CeStoc results, the majority of the PBDEs emitted are transported out of the region through air advection, implying that Stockholm may act as a source for chemical release to other regions. The largest sink for PBDEs in Stockholm is soil, closely followed by sediment, the two compartments together accounting for about 98 % of the total amount remaining in the system. The degree of bromination does not seem to have a large impact on the environmental distribution in this area, but further research on e.g. physical-chemical properties is necessary before this can be finally concluded. Predicted concentrations of individual PBDE congeners in sediment and water lie in the same range as measured levels of individual PCB-congeners, indicating that PBDEs could have an environmental impact of about the same size as the PCBs.

  13. Evaluating the environmental fate of pharmaceuticals using a level III model based on poly-parameter linear free energy relationships

    International Nuclear Information System (INIS)

    Zukowska, Barbara; Breivik, Knut; Wania, Frank

    2006-01-01

    We recently proposed how to expand the applicability of multimedia models towards polar organic chemicals by expressing environmental phase partitioning with the help of poly-parameter linear free energy relationships (PP-LFERs). Here we elaborate on this approach by applying it to three pharmaceutical substances. A PP-LFER-based version of a Level III fugacity model calculates overall persistence, concentrations and intermedia fluxes of polar and non-polar organic chemicals between air, water, soil and sediments at steady-state. Illustrative modeling results for the pharmaceuticals within a defined coastal region are presented and discussed. The model results are highly sensitive to the degradation rate in water and the equilibrium partitioning between organic carbon and water, suggesting that an accurate description of this particular partitioning equilibrium is essential in order to obtain reliable predictions of environmental fate. The PP-LFER based modeling approach furthermore illustrates that the greatest mobility in aqueous phases may be experienced by pharmaceuticals that combines a small molecular size with strong H-acceptor properties

  14. Evaluating the environmental fate of pharmaceuticals using a level III model based on poly-parameter linear free energy relationships

    Energy Technology Data Exchange (ETDEWEB)

    Zukowska, Barbara [Department of Analytical Chemistry, Chemical Faculty, Gdansk University of Technology, 11/12 G. Narutowicza St., 80-952 Gdansk (Poland); Breivik, Knut [NILU- Norwegian Institute for Air Research, P.O. Box 100, NO-2027 Kjeller (Norway)]. E-mail: knut.breivik@nilu.no; Wania, Frank [Department of Physical and Environmental Sciences, University of Toronto at Scarborough, 1265 Military Trail, Scarborough, Ontario, M1C 1A4 (Canada)

    2006-04-15

    We recently proposed how to expand the applicability of multimedia models towards polar organic chemicals by expressing environmental phase partitioning with the help of poly-parameter linear free energy relationships (PP-LFERs). Here we elaborate on this approach by applying it to three pharmaceutical substances. A PP-LFER-based version of a Level III fugacity model calculates overall persistence, concentrations and intermedia fluxes of polar and non-polar organic chemicals between air, water, soil and sediments at steady-state. Illustrative modeling results for the pharmaceuticals within a defined coastal region are presented and discussed. The model results are highly sensitive to the degradation rate in water and the equilibrium partitioning between organic carbon and water, suggesting that an accurate description of this particular partitioning equilibrium is essential in order to obtain reliable predictions of environmental fate. The PP-LFER based modeling approach furthermore illustrates that the greatest mobility in aqueous phases may be experienced by pharmaceuticals that combines a small molecular size with strong H-acceptor properties.

  15. Environmental impact of petroleum products in the soil. Part II: Petroleum products composition and key properties

    International Nuclear Information System (INIS)

    Zerlia, T.

    2001-01-01

    The fate of petroleum hydrocarbons in the soil depends on the chemical-physic properties of each hydrocarbon, as well as on the soil characteristics. The mean composition of various petroleum products, the key chemical compounds and their characteristics are focused in order to outline the environmental behaviour of petroleum hydrocarbons in the soil [it

  16. The fate of cyanide in leach wastes at gold mines: An environmental perspective

    International Nuclear Information System (INIS)

    Johnson, Craig A.

    2015-01-01

    Highlights: • This paper reviews the fate of cyanide in mineral processing wastes at gold mines. • Ore leaching produces numerous cyanide-containing species besides the gold complex. • Many cyanide species are eliminated or sequestered naturally over time. • Sequestered cyanide can be remobilized if conditions change. • Toxicity of released solutions can be reduced by photolytic reactions or offgassing. - Abstract: This paper reviews the basic chemistry of cyanide, methods by which cyanide can be analyzed, and aspects of cyanide behavior that are most relevant to environmental considerations at mineral processing operations associated with gold mines. The emphasis is on research results reported since 1999 and on data gathered for a series of U.S. Geological Survey studies that began in the late 1990s. Cyanide is added to process solutions as the CN − anion, but ore leaching produces numerous other cyanide-containing and cyanide-related species in addition to the desired cyanocomplex of gold. These can include hydrogen cyanide (HCN); cyanometallic complexes of iron, copper, zinc, nickel, and many other metals; cyanate (CNO − ); and thiocyanate (SCN − ). The fate of these species in solid wastes and residual process solutions that remain once gold recovery activities are terminated and in any water that moves beyond the ore processing facility dictates the degree to which cyanide poses a risk to aquatic organisms and aquatic-dependent organisms in the local environment. Cyanide-containing and cyanide-related species are subject to attenuation mechanisms that lead to dispersal to the atmosphere, chemical transformation to other carbon and nitrogen species, or sequestration as cyanometallic precipitates or adsorbed species on mineral surfaces. Dispersal to the atmosphere and chemical transformation amount to permanent elimination of cyanide, whereas sequestration amounts to storage of cyanide in locations from which it can potentially be remobilized by

  17. Environmental fate of hexabromocyclododecane from a new Canadian electronic recycling facility.

    Science.gov (United States)

    Tomko, Geoffrey; McDonald, Karen M

    2013-01-15

    An electronics recycling facility began operation at the municipal landfill site for the City of Edmonton, Canada in March 2008 with the goal of processing 30,000 tonnes of electronic wastes per year. Of the many by-products from the process, brominated fire retardants such as hexabromocyclododecane (HBCD) can evolve off of e-wastes and be released into the environmental media. HBCD has been identified by many countries and international bodies as a chemical of concern because of its ability to bioaccumulate in the ecosystem. An evaluation of the potential emission of HBCD indicates that up to 500 kg per year may be released from a landfill and recycling facility such as that operating in Edmonton. A multimedia fugacity model was used to evaluate the dispersion and fate of atmospherically emitted HBCD traveling into surrounding agricultural land and forested parkland. The model indicates that the three isomers of HBCD partitioned into environmental media similarly. Much of the HBCD is lost through atmospheric advection, but it is also found in soil and sediment. Modeled air concentrations are similar to those measured at locations with a history of e-waste recycling. Since HBCD has been shown to bioaccumulate, the HBCD released from this source has the long-term potential to affect agricultural food crops and the park ecosystem. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. A Review of Environmental Occurrence, Fate, Exposure, and Toxicity of Benzothiazoles.

    Science.gov (United States)

    Liao, Chunyang; Kim, Un-Jung; Kannan, Kurunthachalam

    2018-05-01

    Benzothiazole and its derivatives (BTs) are high production volume chemicals that have been used for several decades in a large number of industrial and consumer products, including vulcanization accelerators, corrosion inhibitors, fungicides, herbicides, algicides, and ultraviolet (UV) light stabilizers. Several benzothiazole derivatives are used commercially, and widespread use of these chemicals has led to ubiquitous occurrence in diverse environmental compartments. BTs have been reported to be dermal sensitizers, respiratory tract irritants, endocrine disruptors, carcinogens, and genotoxicants. This article reviews occurrence and fate of a select group of BTs in the environment, as well as human exposure and toxicity. BTs have frequently been found in various environmental matrices at concentrations ranging from sub-ng/L (surface water) to several tens of μg/g (indoor dust). The use of BTs in a number of consumer products, especially in rubber products, has resulted in widespread human exposure. BTs undergo chemical, biological, and photolytic degradation in the environment, creating several transformation products. Of these, 2-thiocyanomethylthio-benzothiazole (2-SCNMeS-BTH) has been shown to be the most toxic. Epidemiological studies have shown excess risks of cancers, including bladder cancer, lung cancer, and leukemia, among rubber factory workers, particularly those exposed to 2-mercapto-benzothiazole (2-SH-BTH). Human exposure to BTs continues to be a concern.

  19. The environmental fate of polybrominated diphenyl ethers in the Great Lakes Basin

    Science.gov (United States)

    Gouin, Todd William

    Semi-volatile organic compounds, such as the polybrominated diphenyl ethers (PBDEs) have the potential to undergo long-range atmospheric transport (LRAT) to remote locations, which can increase the exposure of sensitive ecosystems to potentially harmful substances. Regulatory instruments, such as the Stockholm Convention on persistent organic pollutants (POPs), have been implemented to limit and/or prevent this exposure. Through the acquisition of scientific data, knowledge can be gained about the environmental fate and human exposure of chemical substances, and the risks associated with using those substances assessed. PBDEs are a class of flame retardants that are used in a wide range of commercial products. In response to growing concern over the detection of PBDEs in remote regions, a number of regulatory bodies have implemented measures to restrict the use of PBDEs. Using a suite of environmental fate models it is shown that PBDEs will most likely partition to organic carbon in soil and sediment, and that their persistence in the environment will be strongly influenced by their reactivity in those compartments. The transport potential of the PBDEs is investigated using the transport and persistence level III model TaPL3, using model environments with and without vegetation. It is suggested that the LRAT potential of the PBDEs is likely to be greater for the more volatile lower brominated congeners than for the higher brominated congeners, and that the LRAT may be sensitive to seasonal changes in the environment, such as temperature, vegetation and changes in precipitation. Furthermore, model results suggest that the PBDEs may be subject to a "spring pulse" effect, whereby concentrations are elevated in air during the early spring. Field studies support the theory of a "spring pulse" effect, where concentrations were observed to be five times greater during the period between snowmelt and bud burst than the average concentration before and after, but conclude

  20. Superficial physicochemical properties of polyurethane biomaterials as osteogenic regulators in human mesenchymal stem cells fates.

    Science.gov (United States)

    Shahrousvand, Mohsen; Sadeghi, Gity Mir Mohamad; Shahrousvand, Ehsan; Ghollasi, Marzieh; Salimi, Ali

    2017-08-01

    All of the cells' interactions are done through their surfaces. Evaluation of surface physicochemical scaffolds along with other factors is important and determines the fate of stem cells. In this work, biodegradable and biocompatible polyester/polyether based polyurethanes (PUs) were synthesized by polycaprolactone diol (PCL) and poly (tetra methylene ether) glycol (PTMEG) as the soft segment. To assess better the impact of surface parameters such as stiffness and roughness effects on osteogenic differentiation of the human mesenchymal stem cell (hMSC), the dimension effect of substrates was eliminated and two-dimensional membranes were produced by synthesized polyurethane. Surface and bulk properties of prepared 2D membranes such as surface chemistry, roughness, stiffness and tensile behavior were evaluated by Attenuated total reflectance Fourier transform infrared (ATR-FTIR), atomic force microscopy (AFM) and tensile behavior. The prepared 2D PU films had suitable hydrophilicity, biodegradability, water absorption, surface roughness and bulk strength. The hMSCs showed greater osteogenesis expression in PU substrates with more roughness and stiffness than others. The results demonstrated that surface parameters along with other differentiation cues have a synergistic effect on stem cells fates. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. An Evaluation of the Environmental Fate and Behavior of Munitions Material (TNT, RDX) in Soil and Plant Systems. Environmental Fate and Behavior of RDX

    Science.gov (United States)

    1990-08-01

    2.2 2.2 SOIL CHARACTERIZATION AND SAMPLING ............................................. 2.7 2.3 PLANT CULTIVATION ...cycle. 2.3 Plant Cultivation and Samoling The chemical fate of RDX in plants was evaluated using bush beans K (Phaseolus vulgaris), wheat (Triticum...particularly in light of the high tissue concentrations observed, may be important from the standpoint of food-chain transfer and ecotoxicology

  2. Fate and Transport of Mercury in Environmental Media and Human Exposure

    Science.gov (United States)

    Kim, Moon-Kyung

    2012-01-01

    Mercury is emitted to the atmosphere from various natural and anthropogenic sources, and degrades with difficulty in the environment. Mercury exists as various species, mainly elemental (Hg0) and divalent (Hg2+) mercury depending on its oxidation states in air and water. Mercury emitted to the atmosphere can be deposited into aqueous environments by wet and dry depositions, and some can be re-emitted into the atmosphere. The deposited mercury species, mainly Hg2+, can react with various organic compounds in water and sediment by biotic reactions mediated by sulfur-reducing bacteria, and abiotic reactions mediated by sunlight photolysis, resulting in conversion into organic mercury such as methylmercury (MeHg). MeHg can be bioaccumulated through the food web in the ecosystem, finally exposing humans who consume fish. For a better understanding of how humans are exposed to mercury in the environment, this review paper summarizes the mechanisms of emission, fate and transport, speciation chemistry, bioaccumulation, levels of contamination in environmental media, and finally exposure assessment of humans. PMID:23230463

  3. Environmental effect and fate of selected phenols in aquatic ecosystems using microcosm approaches

    International Nuclear Information System (INIS)

    Portier, R.J.; Chen, H.M.; Meyers, S.P.

    1983-01-01

    Microbiological studies, together with physicochemical analyses of selected industrial source phenols of environmental significance, were conducted in continuous flow and carbon metabolism microcosms to determine the behavior of these priority pollutants in soil and sediment-water systems typical of coastal wetlands. Phenols used included 4- nitrophenol, 2,4,6-trichlorophenol, 2-chlorophenol, and phenol. The organophosphate, 14 C-UL-Methyl Parathion, was used as a benchmark toxicant control while 14 C-Ring-Phenol was employed for all phenolic compound additions. Microbial diversity, ATP, and specific enzyme systems (i.e., phosphatase, dehydrogenase) were continuously monitored along with 14 CO 2 expiration and 14 C assimilation by the cellular component. Residual analysis of all microcosm tests employed procedures using combined gas chromatography/high-performance liquid chromatography. Statistical analyses were conducted of variations of testing criteria, along with a ranking profile of relative biotransformation and biodegradation potential. Data presented confirm the validity of microcosm approaches and related correlation analysis in toxic substance fate investigations. 17 references, 6 figures, 1 table

  4. Fate and potential environmental effects of methylenediphenyl diisocyanate and toluene diisocyanate released into the atmosphere.

    Science.gov (United States)

    Tury, Bernard; Pemberton, Denis; Bailey, Robert E

    2003-01-01

    Information from a variety of sources has been collected and summarized to facilitate an overview of the atmospheric fate and potential environmental effects of emissions of methylenediphenyl diisocyanate (MDI) or toluene diisocyanate (TDI) to the atmosphere. Atmospheric emissions of both MDI and TDI are low, both in terms of concentration and mass, because of their low volatility and the need for careful control over all aspects of their lifecycle from manufacture through disposal. Typical emission losses for TDI are 25 g/t of TDI used in slabstock foam production. MDI emission losses are lower, often less than 1 g/t of MDI used. Dispersion modeling predicts that concentrations at the fenceline or beyond are very low for typical releases. Laboratory studies show that TDI (and by analogy MDI) does not react with water in the gas phase at a significant rate. The primary degradation reaction of these aromatic diisocyanates in the atmosphere is expected to be oxidation by OH radicals with an estimated half-life of one day. Laboratory studies also show that this reaction is not expected to result in increased ground-level ozone accumulation.

  5. The fate of cyanide in leach wastes at gold mines: an environmental perspective

    Science.gov (United States)

    Johnson, Craig A.

    2015-01-01

    This paper reviews the basic chemistry of cyanide, methods by which cyanide can be analyzed, and aspects of cyanide behavior that are most relevant to environmental considerations at mineral processing operations associated with gold mines. The emphasis is on research results reported since 1999 and on data gathered for a series of U.S. Geological Survey studies that began in the late 1990s. Cyanide is added to process solutions as the CN− anion, but ore leaching produces numerous other cyanide-containing and cyanide-related species in addition to the desired cyanocomplex of gold. These can include hydrogen cyanide (HCN); cyanometallic complexes of iron, copper, zinc, nickel, and many other metals; cyanate (CNO−); and thiocyanate (SCN−). The fate of these species in solid wastes and residual process solutions that remain once gold recovery activities are terminated and in any water that moves beyond the ore processing facility dictates the degree to which cyanide poses a risk to aquatic organisms and aquatic-dependent organisms in the local environment.

  6. Environmental transport and fate of endocrine disruptors from non-potable reuse of municipal wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Hudson, B; Beller, H; Bartel, C M; Kane, S; Campbell, C; Grayson, A; Liu, N; Burastero, S

    2005-11-16

    This project was designed to investigate the important but virtually unstudied topic of the subsurface transport and fate of Endocrine Disrupting Compounds (EDCs) when treated wastewater is used for landscape irrigation (non-potable water reuse). Although potable water reuse was outside the scope of this project, the investigation clearly has relevance to such water recycling practices. The target compounds, which are discussed in the following section and include EDCs such as 4-nonylphenol (NP) and 17{beta}-estradiol, were studied not only because of their potential estrogenic effects on receptors but also because they can be useful as tracers of wastewater residue in groundwater. Since the compounds were expected to occur at very low (part per trillion) concentrations in groundwater, highly selective and sensitive analytical techniques had to be developed for their analysis. This project assessed the distributions of these compounds in wastewater effluents and groundwater, and examined their fate in laboratory soil columns simulating the infiltration of treated wastewater into an aquifer (e.g., as could occur during irrigation of a golf course or park with nonpotable treated water). Bioassays were used to determine the estrogenic activity present in effluents and groundwater, and the results were correlated with those from chemical analysis. In vitro assays for estrogenic activity were employed to provide an integrated measure of estrogenic potency of environmental samples without requiring knowledge or measurement of all bioactive compounds in the samples. For this project, the Las Positas Golf Course (LPGC) in the City of Livermore provided an ideal setting. Since 1978, irrigation of this area with treated wastewater has dominated the overall water budget. For a variety of reasons, a group of 10 monitoring wells were installed to evaluate wastewater impacts on the local groundwater. Additionally, these wells were regularly monitored for tritium ({sup 3}H

  7. Environmental fate and transport of nitroglycerin from propellant residues at firing positions in the unsaturated zone

    Energy Technology Data Exchange (ETDEWEB)

    Bellavance-Godin, A. [Institut National de la Recherche Scientifique, Quebec, PQ (Canada). Eau, Terre et Environnement; Martel, R. [Institut National de la Recherche Scientifique, Varennes, PQ (Canada). Eau, Terre et Environnement, Earth Sciences

    2008-07-01

    In response to environmental concerns, the Canadian Forces Base (CFB) have initiated studies to better evaluate the impact of various military activities. This paper presented the results of a study in which the fate of propellant residues on large soil columns was investigated. The sites selected for the study were the antitank ranges at Garrison Valcartier, Quebec and those at the CFB Petawawa, Ontario. The shoulder rockets fired on those ranges were propelled by solid propellants based on a nitrocellulose matrix in which nitroglycerine and ammonium perchlorate were dispersed as oxidizer and energetic materials. Propellant residues accumulated in the surface soils because the combustion processes in the rockets was incomplete. This study evaluated the contaminants transport through the unsaturated zone. Sampling was conducted in 2 steps. The first involved collecting uncontaminated soil samples representative of the geological formations of the 2 sites. The second step involved collecting soils containing high levels of propellant residues behind antitank firing positions, which was later spread across the surface of the uncontaminated soil columns and which were representative of the contaminated zone. The soils were watered in the laboratory following the precipitation patterns of the respective regions and interstitial water output of the columns was also sampled. The compounds of interest were nitroglycerine and its degradation metabolites, dinitroglycerine, mononitroglycerine and nitrates as well as perchlorate and bromides. Results presented high concentrations of nitrites, nitrates and perchlorates. Both the NG and its degradation products were monitored using a newly developed analytical method that provides for a better understanding of NG degradation pathways in anaerobic conditions. 12 refs., 3 tabs., 12 figs.

  8. Source apportionment and environmental fate of lead chromates in atmospheric dust in arid environments.

    Science.gov (United States)

    Meza-Figueroa, Diana; González-Grijalva, Belem; Romero, Francisco; Ruiz, Joaquin; Pedroza-Montero, Martín; Rivero, Carlos Ibañez-Del; Acosta-Elías, Mónica; Ochoa-Landin, Lucas; Navarro-Espinoza, Sofía

    2018-03-07

    The environmental fate of lead derived from traffic paint has been poorly studied in developing countries, mainly in arid zones. For this purpose, a developing city located in the Sonoran desert (Hermosillo, Mexico), was chosen to conduct a study. In this paper the lead chromate (crocoite) sources in atmospheric dust were addressed using a combination of Raman microspectroscopy, X-ray diffraction, scanning electron microscopy (SEM), and Pb isotope measurements. A high concentration of Pb and Cr as micro- and nanostructured pigments of crocoite is reported in yellow traffic paint (n=80), road dust (n=146), settled dust in roofs (n=21), and atmospheric dust (n=20) from a developing city located in the Sonoran Desert. 10 samples of peri-urban soils were collected for local geochemical background. The paint photodegradation and erosion of the asphaltic cover are enhanced by the climate, and the presence of the mineral crocoite (PbCrO 4 ) in road dust with an aerodynamic diameter ranging from 100nm to 2μm suggests its integration into the atmosphere by wind resuspension processes. A positive PbCr correlation (R 2 =0.977) was found for all studied samples, suggesting a common source. The Pb-isotope data show signatures in atmospheric dust as a product of the mixing of two end members: i) local soils and ii) crocoite crystals as pigments in paint. The presence of lead chromates in atmospheric dust has not been previously documented in Latin America, and it represents an unknown health risk to the exposed population because the identified size of crystals can reach the deepest part of lungs. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Evaluating the environmental fate of short-chain chlorinated paraffins (SCCPs) in the Nordic environment using a dynamic multimedia model.

    Science.gov (United States)

    Krogseth, Ingjerd S; Breivik, Knut; Arnot, Jon A; Wania, Frank; Borgen, Anders R; Schlabach, Martin

    2013-12-01

    Short chain chlorinated paraffins (SCCPs) raise concerns due to their potential for persistence, bioaccumulation, long-range transport and adverse effects. An understanding of their environmental fate remains limited, partly due to the complexity of the mixture. The purpose of this study was to evaluate whether a mechanistic, integrated, dynamic environmental fate and bioaccumulation multimedia model (CoZMoMAN) can reconcile what is known about environmental emissions and human exposure of SCCPs in the Nordic environment. Realistic SCCP emission scenarios, resolved by formula group, were estimated and used to predict the composition and concentrations of SCCPs in the environment and the human food chain. Emissions at the upper end of the estimated range resulted in predicted total concentrations that were often within a factor of 6 of observations. Similar model performance for a complex group of organic contaminants as for the well-known polychlorinated biphenyls strengthens the confidence in the CoZMoMAN model and implies a relatively good mechanistic understanding of the environmental fate of SCCPs. However, the degree of chlorination predicted for SCCPs in sediments, fish, and humans was higher than observed and poorly established environmental half-lives and biotransformation rate constants contributed to the uncertainties in the predicted composition and ∑SCCP concentrations. Improving prediction of the SCCP composition will also require better constrained estimates of the composition of SCCP emissions. There is, however, also large uncertainty and lack of coherence in the existing observations, and better model-measurement agreement will require improved analytical methods and more strategic sampling. More measurements of SCCP levels and compositions in samples from background regions are particularly important.

  10. Biological degradation of triclocarban and triclosan in a soil under aerobic and anaerobic conditions and comparison with environmental fate modelling

    Energy Technology Data Exchange (ETDEWEB)

    Guangguo, Ying [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); CSIRO Land and Water, Adelaide Laboratory, PMB2, Glen Osmond SA 5064 (Australia)], E-mail: guang-guo.ying@gig.ac.cn; Xiangyang, Yu [CSIRO Land and Water, Adelaide Laboratory, PMB2, Glen Osmond SA 5064 (Australia); Food Safety Research Institute, Jiangsu Academy of Agricultural Sciences, Nanjing 210014 (China); Kookana, Rai S [CSIRO Land and Water, Adelaide Laboratory, PMB2, Glen Osmond SA 5064 (Australia)

    2007-12-15

    Triclocarban and triclosan are two antimicrobial agents widely used in many personal care products. Their biodegradation behaviour in soil was investigated by laboratory degradation experiments and environmental fate modelling. Quantitative structure-activity relationship (QSAR) analyses showed that triclocarban and triclosan had a tendency to partition into soil or sediment in the environment. Fate modelling suggests that either triclocarban or triclosan 'does not degrade fast' with its primary biodegradation half-life of 'weeks' and ultimate biodegradation half-life of 'months'. Laboratory experiments showed that triclocarban and triclosan were degraded in the aerobic soil with half-life of 108 days and 18 days, respectively. No negative effect of these two antimicrobial agents on soil microbial activity was observed in the aerobic soil samples during the experiments. But these two compounds persisted in the anaerobic soil within 70 days of the experimental period. - Triclocarban and triclosan can be degraded by microbial processes in aerobic soil, but will persist in anaerobic soil.

  11. Biological degradation of triclocarban and triclosan in a soil under aerobic and anaerobic conditions and comparison with environmental fate modelling

    International Nuclear Information System (INIS)

    Ying Guangguo; Yu Xiangyang; Kookana, Rai S.

    2007-01-01

    Triclocarban and triclosan are two antimicrobial agents widely used in many personal care products. Their biodegradation behaviour in soil was investigated by laboratory degradation experiments and environmental fate modelling. Quantitative structure-activity relationship (QSAR) analyses showed that triclocarban and triclosan had a tendency to partition into soil or sediment in the environment. Fate modelling suggests that either triclocarban or triclosan 'does not degrade fast' with its primary biodegradation half-life of 'weeks' and ultimate biodegradation half-life of 'months'. Laboratory experiments showed that triclocarban and triclosan were degraded in the aerobic soil with half-life of 108 days and 18 days, respectively. No negative effect of these two antimicrobial agents on soil microbial activity was observed in the aerobic soil samples during the experiments. But these two compounds persisted in the anaerobic soil within 70 days of the experimental period. - Triclocarban and triclosan can be degraded by microbial processes in aerobic soil, but will persist in anaerobic soil

  12. Fate of Eight Different Polymers under Uncontrolled Composting Conditions: Relationships Between Deterioration, Biofilm Formation, and the Material Surface Properties.

    Science.gov (United States)

    Mercier, Anne; Gravouil, Kevin; Aucher, Willy; Brosset-Vincent, Sandra; Kadri, Linette; Colas, Jenny; Bouchon, Didier; Ferreira, Thierry

    2017-02-21

    With the ever-increasing volume of polymer wastes and their associated detrimental impacts on the environment, the plastic life cycle has drawn increasing attention. Here, eight commercial polymers selected from biodegradable to environmentally persistent materials, all formulated under a credit card format, were incubated in an outdoor compost to evaluate their fate over time and to profile the microbial communities colonizing their surfaces. After 450 days in compost, the samples were all colonized by multispecies biofilms, these latest displaying different amounts of adhered microbial biomass and significantly distinct bacterial and fungal community compositions depending on the substrate. Interestingly, colonization experiments on the eight polymers revealed a large core of shared microbial taxa, predominantly composed of microorganisms previously reported from environments contaminated with petroleum hydrocarbons or plastics debris. These observations suggest that biofilms may contribute to the alteration process of all the polymers studied. Actually, four substrates, independently of their assignment to a polymer group, displayed a significant deterioration, which might be attributed to biologically mediated mechanisms. Relevantly, the deterioration appears strongly associated with the formation of a high-cell density biofilm onto the polymer surfaces. The analysis of various surface properties revealed that roughness and hydrophilicity are likely prominent parameters for driving the biological interactions with the polymers.

  13. Environmental audits of oil and gas properties

    International Nuclear Information System (INIS)

    Moody, T.D.; Forbes, S.

    1991-01-01

    The growing concern over one, the cost of correcting environmental damage and two, the potential financial liabilities associated with the acquisition, sale or lease of oil and gas properties, has led many prospective buyers to investigate the environmental liabilities associated with the property transfer. The environmental audit provides a tool or mechanism to assist the prudent investor in identifying environmental problems that could adversely effect an otherwise normal business activity. Accordingly, an environmental audit can identify potential environmental liabilities associated with the property, thus allowing the investor an opportunity to better assess financial risks. In addition, should the negative findings of the environmental audit be limited, the findings could be used by the buyer in negotiating the final price of the subject property to account for potential or known liabilities. As this suggests, environmental damage to an oil and gas property does not necessarily render the property worthless. This paper provides a brief guide on environmental audits of oil and gas properties as well as general information on the most common exploration and production wastes

  14. Exposure levels, environmental fate modelling and human health risk assessment of lindane in Ghana

    International Nuclear Information System (INIS)

    Adu-Kumi, S.

    2011-01-01

    -HCH which is a known environmental estrogen, was predominant contaminant measured (geometric mean concentrations 4.18 ng g -1 lipid wt. and 4.35 ng g -1 lipid wt. for pooled and individual samples respectively). The levels of Lindane, α-HCH and β-HCH in edible fish (catfish and tilapia) sourced from Lake Bosumtwi and the Weija Lake, were concurrently investigated using HRGC/HRMS. Concentrations of HCHs were found to be generally low (mainly limits of detection) probably reflecting the historical use of Lindane and technical HCH mixtures. Catfish sourced from Lake Volta (purchased from the Madina market) however contained appreciable amounts of Lindane (average concentration of 0.72 ng g -1 lipid wt). Measured values are lower than the maximum acceptable limit for human consumption established by the FAO/WHO (FAO/WHO, 1986). Hence there is no potential health risk from HCHs (Lindane, α-HCH and β-HCH) in fish for the general population of Ghana. Level III and level IV fugacity models were successfully applied to investigate the environmental fate of Lindane in the compartments of air, water, sediment, soil and biota (fish). Model estimates showed that air, water, soil and fish constitute important exposure pathways of Lindane for the general population of Ghana. The estimated total amount of Lindane accumulated in all media at steady-state was 136 tonnes, the soil compartment accounting for ore than 97% of the total accumulation. Time trends in concentration and fluxes simulated in for the period 1959-2020 predicted that less than 1% of the 2002 concentration levels of Lindane in air, water and soil, respectively, will be left in 2020. Finally, health risks associated with the exposure of the general population of Ghana to Lindane via the pathways of air, water, soil, food (or diet) were characterized using the combined field measurements and results of the multi-media environmental fate modelling. Diet (mainly vegetables), soil and to a lesser extent water constituted

  15. Interaction of Physical and Chemical Processes Controlling the Environmental Fate and Transport of Lampricides Through Stream-Hyporheic Systems

    Science.gov (United States)

    Hixson, J.; Ward, A. S.; Schmadel, N.; McConville, M.; Remucal, C.

    2016-12-01

    The transport and fate of contaminants of emerging concern through the environment is complicated by the heterogeneity of natural systems and the unique reaction pathways of individual compounds. Our current evaluation of risk is often simplified to controls assumed to be homogeneous in space and time. However, we know spatial heterogeneity and time-variable reaction rates complicate predictions of environmental transport and fate, and therefore risk. These complications are the result of the interactions between the physical and chemical systems and the time-variable equilibrium that exists between the two. Compounds that interact with both systems, such as photolytic compounds, require that both components are fully understood in order to predict transport and fate. Release of photolytic compounds occurs through both unintentional releases and intentional loadings. Evaluating risks associated with unintentional releases and implementing best management practices for intentional releases requires an in-depth understanding of the sensitivity of photolytic compounds to external controls. Lampricides, such as 3-trifluoromethyl-4-nitrophenol (TFM), are broadly applied in the Great Lakes system to control the population of invasive sea lamprey. Over-dosing can yield fish kills and other detrimental impacts. Still, planning accounts for time of passage and dilution, but not the interaction of the physical and chemical systems (i.e., storage in the hyporheic zone and time-variable decay rates). In this study, we model a series of TFM applications to test the efficacy of dosing as a function of system characteristics. Overall, our results demonstrate the complexity associated with photo-sensitive compounds through stream-hyporheic systems, and highlight the need to better understand how physical and chemical systems interact to control transport and fate in the environment.

  16. Parameters for the Evaluation of the Fate, Transport, and Environmental Impacts of Chemical Agents in Marine Environments

    Science.gov (United States)

    2007-07-01

    Anal. Bering/Chukchi, accessed 3 January 2007, http://www.osdpd.noaa.gov/PSB/EPS/SST/data/beringst.c.gif. RE-2 15 Brewer , P. G.; Glover, D. M...Highly Purified Mustard Gas and its Action on Yeast , ” J. Am. Chem. Soc., 1947, 69(7), 1808-1809. 135 Redemann, C. E.; Chaikin, S. W.; Fearing, R. B...171 MacNaughton, M. G.; Brewer , J. H., Environmental Chemistry and Fate of Chemical Warfare Agents, Southwest Research Institute, San Antonio TX, 1994

  17. Characterizing fate and transport properties in karst aquifers under different hydrologic conditions

    Science.gov (United States)

    Rodriguez, E.; Padilla, I. Y.

    2017-12-01

    Karst landscapes contain very productive aquifers. The hydraulic and hydrogeological characteristics of karst aquifers make these systems capable of storing and transporting large amount of water, but also highly vulnerable to contamination. Their extremely heterogeneous nature prevents accurate prediction in contaminant fate and transport. Even more challenging is to understand the impact of hydrologic conditions changes on fate and transport processes. This studies aims at characterizing fate and transport processes in the karst groundwater system of northern Puerto Rico under different hydrologic conditions. The study involves injecting rhodamine and uranine dyes into a sinkhole, and monitoring concentrations at a spring. Results show incomplete recovery of tracers, but breaking curves can be used to estimate advective, dispersive and mass transfer characteristic of the karst system. Preliminary results suggest significant differences in fate and transport characteristics under different hydrologic conditions.

  18. Enantioselective stable isotope analysis (ESIA) — A new concept to evaluate the environmental fate of chiral organic contaminants

    International Nuclear Information System (INIS)

    Badea, Silviu-Laurentiu; Danet, Andrei-Florin

    2015-01-01

    Since 2011, the enantiospecific stable carbon isotope analysis (ESIA) has emerged as an innovative technique to assess the environmental fate of chiral emerging compounds by combining in one experimental technique both compound specific isotope analysis (CSIA) and enantioselective analysis. To date, the ESIA was applied for four classes of compounds: α-hexachlorocyclohexane (α-HCH), polar herbicides (phenoxy acids), synthetic polycyclic musk galaxolide (HHCB), and phenoxyalkanoic methyl herbicides. From an analytical point of view there are factors that are hindering the application of ESIA methods for the field samples: (i.e. amounts of target analyte, matrix effects, GC resolution) and overcoming these factors is challenging. While ESIA was shown as a mature technique for the first three abovementioned class of compounds, no isotope analysis of individual enantiomers could be performed for phenoxyalkanoic methyl herbicides. With respect to field studies, one study showed that ESIA might be a promising tool to distinguish between biotic and abiotic transformation pathways of chiral organic contaminants and even to differentiate between their aerobic and anaerobic biotransformation pathways. The development of ESIA methods for new chiral emerging contaminants in combination with development of multi-element isotope analysis will contribute to a better characterization of transformation pathways of chiral organic contaminants. - Highlights: • ESIA is an innovative technique to assess the environmental fate of chiral pollutants • Overcoming the analytical limitations of ESIA is challenging • Development of ESIA methods for new chiral emerging contaminants is needed

  19. Enantioselective stable isotope analysis (ESIA) — A new concept to evaluate the environmental fate of chiral organic contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Badea, Silviu-Laurentiu, E-mail: badeasilviu@gmail.com [Department of Chemistry, Umeå University, SE-901 87 Umeå (Sweden); Danet, Andrei-Florin [Department of Analytical Chemistry, University of Bucharest, Faculty of Chemistry, 90-92 Panduri Str., Bucharest 050657 (Romania)

    2015-05-01

    Since 2011, the enantiospecific stable carbon isotope analysis (ESIA) has emerged as an innovative technique to assess the environmental fate of chiral emerging compounds by combining in one experimental technique both compound specific isotope analysis (CSIA) and enantioselective analysis. To date, the ESIA was applied for four classes of compounds: α-hexachlorocyclohexane (α-HCH), polar herbicides (phenoxy acids), synthetic polycyclic musk galaxolide (HHCB), and phenoxyalkanoic methyl herbicides. From an analytical point of view there are factors that are hindering the application of ESIA methods for the field samples: (i.e. amounts of target analyte, matrix effects, GC resolution) and overcoming these factors is challenging. While ESIA was shown as a mature technique for the first three abovementioned class of compounds, no isotope analysis of individual enantiomers could be performed for phenoxyalkanoic methyl herbicides. With respect to field studies, one study showed that ESIA might be a promising tool to distinguish between biotic and abiotic transformation pathways of chiral organic contaminants and even to differentiate between their aerobic and anaerobic biotransformation pathways. The development of ESIA methods for new chiral emerging contaminants in combination with development of multi-element isotope analysis will contribute to a better characterization of transformation pathways of chiral organic contaminants. - Highlights: • ESIA is an innovative technique to assess the environmental fate of chiral pollutants • Overcoming the analytical limitations of ESIA is challenging • Development of ESIA methods for new chiral emerging contaminants is needed.

  20. In silico environmental chemical science: properties and processes from statistical and computational modelling

    Energy Technology Data Exchange (ETDEWEB)

    Tratnyek, P. G.; Bylaska, Eric J.; Weber, Eric J.

    2017-01-01

    Quantitative structure–activity relationships (QSARs) have long been used in the environmental sciences. More recently, molecular modeling and chemoinformatic methods have become widespread. These methods have the potential to expand and accelerate advances in environmental chemistry because they complement observational and experimental data with “in silico” results and analysis. The opportunities and challenges that arise at the intersection between statistical and theoretical in silico methods are most apparent in the context of properties that determine the environmental fate and effects of chemical contaminants (degradation rate constants, partition coefficients, toxicities, etc.). The main example of this is the calibration of QSARs using descriptor variable data calculated from molecular modeling, which can make QSARs more useful for predicting property data that are unavailable, but also can make them more powerful tools for diagnosis of fate determining pathways and mechanisms. Emerging opportunities for “in silico environmental chemical science” are to move beyond the calculation of specific chemical properties using statistical models and toward more fully in silico models, prediction of transformation pathways and products, incorporation of environmental factors into model predictions, integration of databases and predictive models into more comprehensive and efficient tools for exposure assessment, and extending the applicability of all the above from chemicals to biologicals and materials.

  1. In silico environmental chemical science: properties and processes from statistical and computational modelling.

    Science.gov (United States)

    Tratnyek, Paul G; Bylaska, Eric J; Weber, Eric J

    2017-03-22

    Quantitative structure-activity relationships (QSARs) have long been used in the environmental sciences. More recently, molecular modeling and chemoinformatic methods have become widespread. These methods have the potential to expand and accelerate advances in environmental chemistry because they complement observational and experimental data with "in silico" results and analysis. The opportunities and challenges that arise at the intersection between statistical and theoretical in silico methods are most apparent in the context of properties that determine the environmental fate and effects of chemical contaminants (degradation rate constants, partition coefficients, toxicities, etc.). The main example of this is the calibration of QSARs using descriptor variable data calculated from molecular modeling, which can make QSARs more useful for predicting property data that are unavailable, but also can make them more powerful tools for diagnosis of fate determining pathways and mechanisms. Emerging opportunities for "in silico environmental chemical science" are to move beyond the calculation of specific chemical properties using statistical models and toward more fully in silico models, prediction of transformation pathways and products, incorporation of environmental factors into model predictions, integration of databases and predictive models into more comprehensive and efficient tools for exposure assessment, and extending the applicability of all the above from chemicals to biologicals and materials.

  2. Linking the environmental loads to the fate of PPCPs in Beijing: Considering both the treated and untreated wastewater sources

    International Nuclear Information System (INIS)

    Wang, Bin; Dai, Guohua; Deng, Shubo; Huang, Jun; Wang, Yujue; Yu, Gang

    2015-01-01

    The environmental loads of pharmaceutical and personal care products (PPCPs) in Beijing were estimated from direct discharge of untreated wastewater and WWTP treated effluent. The annual environmental loads of 15 PPCP components ranged from 16.3 kg (propranolol) to 9.85 tons (caffeine). A fugacity model was developed to successfully estimate the PPCP pollution based on the estimated environmental load. The modeled results approximated the observed PPCP concentrations in Beijing. The untreated wastewater contributed significantly to PPCP pollution in Beijing, ranging from 46% (propranolol) to 99% (caffeine). The total environmental burden of target PPCPs ranged from 0.90 kg (propranolol) to 536 kg (caffeine). Water is the most important media for the fate of PPCPs. Monte Carlo-based concentration distributions of PPCPs are consistent with the observed results. The most important way to reduce the PPCP pollution is to both improve wastewater collection rate and adopt deep treatment technologies. - Highlights: • Annual environmental loads of PPCPs ranged from 16.3 kg to 9.85 tons in Beijing. • The environmental loads can be linked to PPCP pollution by fugacity model. • Untreated wastewater significantly contributed to PPCP pollution in Beijing. • The environmental burden of 15 PPCPs in Beijing ranged from 0.90 kg to 536 kg. • Uncertainty simulation successfully generated PPCP concentration distribution. - The environmental loads from both the treated and untreated wastewater sources contribute to PPCPs pollution in the surface water in Beijing, China

  3. Elemental mercury: Its unique properties affect its behavior and fate in the environment

    International Nuclear Information System (INIS)

    Gonzalez-Raymat, Hansell; Liu, Guangliang; Liriano, Carolina; Li, Yanbin; Yin, Yongguang; Shi, Jianbo; Jiang, Guibin; Cai, Yong

    2017-01-01

    Elemental mercury (Hg 0 ) has different behavior in the environment compared to other pollutants due to its unique properties. It can remain in the atmosphere for long periods of time and so can travel long distances. Through air-surface (e.g., vegetation or ocean) exchange (dry deposition), Hg 0 can enter terrestrial and aquatic systems where it can be converted into other Hg species. Despite being ubiquitous and playing a key role in Hg biogeochemical cycling, Hg 0 behavior in the environment is not well understood. The objective of this review is to provide a better understanding of how the unique physicochemical properties of Hg 0 affects its cycling and chemical transformations in different environmental compartments. The first part focuses on the fundamental chemistry of Hg 0 , addressing why Hg 0 is liquid at room temperature and the formation of amalgam, Hg halide, and Hg chalcogenides. The following sections discuss the long-range transport of Hg 0 as well as its redistribution in the atmosphere, aquatic and terrestrial systems, in particular, on the sorption/desorption processes that occur in each environmental compartment as well as the involvement of Hg 0 in chemical transformation processes driven by photochemical, abiotic, and biotic reactions. - Highlights: • Unique property of Hg 0 make it to behave differently with other toxic metals. • Hg 0 is considered the only global metal pollutant due to its uniqueness. • Hg 0 can be easily transformed and efficiently redistributed in the environments. - A better understanding of the properties and behavior of Hg 0 is the key to elucidate the biogeochemical cycling of mercury, a global pollutant in the environment.

  4. Environmental fate of fungicides and other current-use pesticides in a central California estuary

    Science.gov (United States)

    Smalling, Kelly L.; Kuivila, Kathryn; Orlando, James L.; Phillips, Bryn M.; Anderson, Brian S.; Siegler, Katie; Hunt, John W.; Hamilton, Mary

    2013-01-01

    The current study documents the fate of current-use pesticides in an agriculturally-dominated central California coastal estuary by focusing on the occurrence in water, sediment and tissue of resident aquatic organisms. Three fungicides (azoxystrobin, boscalid, and pyraclostrobin), one herbicide (propyzamide) and two organophosphate insecticides (chlorpyrifos and diazinon) were detected frequently. Dissolved pesticide concentrations in the estuary corresponded to the timing of application while bed sediment pesticide concentrations correlated with the distance from potential sources. Fungicides and insecticides were detected frequently in fish and invertebrates collected near the mouth of the estuary and the contaminant profiles differed from the sediment and water collected. This is the first study to document the occurrence of many current-use pesticides, including fungicides, in tissue. Limited information is available on the uptake, accumulation and effects of current-use pesticides on non-target organisms. Additional data are needed to understand the impacts of pesticides, especially in small agriculturally-dominated estuaries.

  5. Predictions by the multimedia environmental fate model SimpleBox compared to field data: Intermedia concentration ratios of two phthalate esters

    NARCIS (Netherlands)

    Struijs J; Peijnenburg WJGM; ECO

    2003-01-01

    The multimedia environmental fate model SimpleBox is applied to compute steady-state concentration ratios with the aim to harmonize environmetal quality objectives of air, water, sediment and soil. In 1995 the Dutch Health Council recommended validation of the model. Several activities were

  6. Environmental Fate of the Herbicide Fluazifop-P-butyl and Its Degradation Products in Two Loamy Agricultural Soils: A Combined Laboratory and Field Study

    DEFF Research Database (Denmark)

    Badawi, Nora; Rosenbom, Anette E.; Olsen, Preben

    2015-01-01

    The herbicide fluazifop-P-butyl (FPB) is used against grasses in agricultural crops such as potato, oilseed rape and sugar beet. Limited information is available in Scientific literature on its environmental fate, therefore extensive monitoring at two agricultural test fields was combined...

  7. Environmental fate of roxarsone in poultry litter. I. Degradation of roxarsone during composting

    Science.gov (United States)

    Garbarino, J.R.; Bednar, A.J.; Rutherford, D.W.; Beyer, R.S.; Wershaw, R. L.

    2003-01-01

    Roxarsone, 3-nitro-4-hydroxyphenylarsonic acid, is an organoarsenic compound that is used extensively in the feed of broiler poultryto control coccidial intestinal parasites, improve feed efficiency, and promote rapid growth. Nearly all the roxarsone in the feed is excreted unchanged in the manure. Poultry litter composed of the manure and bedding material has a high nutrient content and is used routinely as a fertilizer on cropland and pasture. Investigations were conducted to determine the fate of poultrylitter roxarsone in the environment. Experiments indicated that roxarsone was stable in fresh dried litter; the primary arsenic species extracted with water from dried litter was roxarsone. However, when water was added to litter at about 50 wt % and the mixture was allowed to compost at 40oC, the speciation of arsenic shifted from roxarsone to primarily arsenate in about 30 days. Increasing the amount of water increased the rate of degradation. Experiments also suggested that the degradation process most likely was biotic in nature. The rate of degradation was directly proportional to the incubation temperature; heat sterilization eliminated the degradation. Biotic degradation also was supported by results from enterobacteriaceae growth media that were inoculated with litter slurry to enhance the biotic processes and to reduce the concomitant abiotic effects from the complex litter solution. Samples collected from a variety of litter windrows in Arkansas, Oklahoma, and Maryland also showed that roxarsone originally present had been converted to arsenate.

  8. Phytoaccumulation of antimicrobials from biosolids: impacts on environmental fate and relevance to human exposure.

    Science.gov (United States)

    Aryal, Niroj; Reinhold, Dawn M

    2011-11-01

    Triclocarban and triclosan, two antimicrobials widely used in consumer products, can adversely affect ecosystems and potentially impact human health. The application of biosolids to agricultural fields introduces triclocarban and triclosan to soil and water resources. This research examined the phytoaccumulation of antimicrobials, effects of plant growth on migration of antimicrobials to water resources, and relevance of phytoaccumulation in human exposure to antimicrobials. Pumpkin, zucchini, and switch grass were grown in soil columns to which biosolids were applied. Leachate from soil columns was assessed every other week for triclocarban and triclosan. At the end of the trial, concentrations of triclocarban and triclosan were determined for soil, roots, stems, and leaves. Results indicated that plants can reduce leaching of antimicrobials to water resources. Pumpkin and zucchini growth significantly reduced soil concentrations of triclosan to less than 0.001 mg/kg, while zucchini significantly reduced soil concentrations of triclocarban to 0.04 mg/kg. Pumpkin, zucchini, and switch grass accumulated triclocarban and triclosan in mg per kg (dry) concentrations. Potential human exposure to triclocarban from consumption of pumpkin or zucchini was substantially less than exposure from product use, but was greater than exposure from drinking water consumption. Consequently, research indicated that pumpkin and zucchini may beneficially impact the fate of antimicrobials in agricultural fields, while presenting minimal acute risk to human health. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. From consumption to harvest: Environmental fate prediction of excreted ionizable trace organic chemicals

    DEFF Research Database (Denmark)

    Polesel, Fabio; Plósz, Benedek G.; Trapp, Stefan

    2015-01-01

    Excreted trace organic chemicals, e.g., pharmaceuticals and biocides, typically undergo incomplete elimination in municipal wastewater treatment plants (WWTPs) and are released to surface water via treated effluents and to agricultural soils through sludge amendment and/or irrigation with freshwa......Excreted trace organic chemicals, e.g., pharmaceuticals and biocides, typically undergo incomplete elimination in municipal wastewater treatment plants (WWTPs) and are released to surface water via treated effluents and to agricultural soils through sludge amendment and/or irrigation...... with freshwater or reclaimed wastewater. Recent research has shown the tendency for these substances to accumulate in food crops. In this study, we developed and applied a simulation tool to predict the fate of three ionizable trace chemicals (triclosan-TCS, furosemide-FUR, ciprofloxacin-CIP) from human...... and a recently developed dynamic soil-plant uptake model. The simulation tool was tested using country-specific (e.g., consumption/emission rates, precipitation and temperature) input data. A Monte Carlo-based approach was adopted to account for the uncertainty associated to physico-chemical and biokinetic model...

  10. Transformation of triphenyltin by Eubacteria: Fate and effects in environmental system

    Digital Repository Service at National Institute of Oceanography (India)

    Jadhav, S.

    and organisms. Knowledge about the environmental concentrations of any chemical compound is required to understand its effects on the system. Presence of such compounds in the environment is a serious threat and danger for human health and aquatic organisms...

  11. Environmental fate of depleted uranium at three sites contaminated during the balkan conflict

    International Nuclear Information System (INIS)

    Radenkovic, M.; Joksic, J.; Todorovic, D.; Kovacevic, M.

    2006-01-01

    A study on depleted uranium fate in the sites contaminated during the 1999 war conflict in Serbia was conducted in phases until the clean up activities were completed. The ammunition remains found at the locations in the surface soil were collected in the first phase during the radiation survey of the affected areas. The most of depleted uranium penetrators left buried deep into the ground exposed to the weathering and corrosion processes. The contamination level in the air, water, soil and bio -indicators was controlled all the time by routine gamma and alpha spectrometry measurements. Depleted uranium migration was studied through the soil profile surrounding the penetrator during the 2001 at the Bratoselce location showing the contamination level fall to the 1% of its value at approximately 15 cm distance to the source. The samples taken from the soil layers at different distances in the profile are subjected to a modified Tessiers five-step sequential extraction procedure. The uranium and heavy metals contents were determined in the obtained fractions. Results have specified carbonates and iron hydrous-oxides as the most probable substrates for uranium physical/chemical associations formed in the soil for the time elapsed. A very strong dependence of substrate onto contamination level was found. The correlation of uranium and other heavy metals was obtained. The 234 U/ 238 U and 235 U/ 238 U ratios are determined in extracts by alpha spectrometry after appropriate radiochemical separation procedure and thin alpha sources electroplating. The analysis has shown the share of depleted in total uranium content in exchangeable, carbonate, hydrous or crystalline iron/manganese, organic and residue phases indicating the bioavailability of depleted uranium present in the soil. The results are discussed related to detailed geochemical analysis of the particular soil type common for this region. Depleted uranium content in soil samples taken at the locations after the

  12. US Geological Survey research on the environmental fate of uranium mining and milling wastes

    International Nuclear Information System (INIS)

    Landa, E.R.; Gray, J.R.

    1995-01-01

    Studies by the US Geological Survey (USGS) of uranium mill tailings (UMT) have focused on characterizing the forms in which radionuclides are retained and identifying factors influencing the release of radionuclides to air and water. Selective extraction studies and studies of radionuclide sorption by and reaching from components of UMT showed alkaline earth sulfate and hydrous ferric oxides to be important hosts of radium-226 ( 226 Ra) in UMT. Extrapolating from studies of barite dissolution in anerobic lake sediments, the leaching of 226 Ra from UMT by sulfate-reducing bacteria was investigated; a marked increase in 226 Ra release to aqueous solution as compared to sterile controls was demonstrated. A similar action of iron(III)-reducing bacteria was later shown. Ion exchangers such as clay minerals can also promote the dissolution of host-phase minerals and thereby influence the fate of radionuclides such as 226 Ra. Radon release studies examined particle size and ore composition as variables. Aggregation of UMT particles was shown to mask the higher emanating fraction of finer particles. Studies of various ores and ore components showed that UMT cannot be assumed to have the same radon-release characteristics as their precursor ores, nor can 226 Ra retained by various substrates be assumed to emanate the same fraction of radon. Over the last decade, USGS research directed at offsite mobility of radionuclides form uranium mining and milling processes has focused on six areas: the Midnite Mine in Washington; Ralston Creek and Reservoir, Colorado; sites near Canon City, Colorado; the Monument Valley District of Arizona and Utah; the Cameron District of Arizona; and the Puerco River basin of Arizona and New Mexico. 48 refs., 6 figs., 4 tabs

  13. 40 CFR 158.2174 - Experimental use permit microbial pesticides nontarget organisms and environmental fate data...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Experimental use permit microbial... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS... controls the target insect pest by a mechanism of infectivity; i.e., may create an epizootic condition in...

  14. Some basic properties of environmentally adapted oils

    Energy Technology Data Exchange (ETDEWEB)

    Hoeglund, E. [Div. of Machine Elements, Luleaa University of Technology (Sweden)

    1998-11-01

    Environmental concern has led to a development of lubricants that are less harmful to the environmental than traditional mineral based oils. Biodegradability and non-toxicity are desired properties together with a competitive price and if possible they should also be derived from renewable raw materials. In order to have a major breakthrough for the new, environmentally adapted lubricating oils they must perform well in mechanical and hydraulic systems. They must reduce wear, increase efficiency and reduce maintenance costs equally well, or preferably better than mineral based oils. This paper presents primary results from an investigation where four environmentally adapted oils (rape seed, pine tree, diester and TMP-ester) are compared to a conventional naphthenic mineral oil. Viscosity and viscosity-pressure coefficients, limiting shear stress, friction properties and film forming ability have been evaluated under elastohydrodynamic conditions. It was found that the mineral oil had the highest values of pressure-viscosity coefficient, limiting shear stress and coefficient of friction. Rape seed oil had the second highest pressure-viscosity coefficient but the lowest limiting shear stress and coefficient of friction. Pine tree oil, diester and TMP-ester formed an intermediate group with rather similar results. The Hamrock-Dowson equation for central film thickness was found to overestimate film thickness by about 10-20 per cent with the least discrepancy for the mineral oil. (orig.) 8 refs.

  15. Development and application of the microbial fate and transport module for the Agricultural Policy/Environmental eXtender (APEX) model

    Science.gov (United States)

    Hong, E.; Park, Y.; Muirhead, R.; Jeong, J.; Pachepsky, Y. A.

    2017-12-01

    Pathogenic microorganisms in recreational and irrigation waters remain the subject of concern. Water quality models are used to estimate microbial quality of water sources, to evaluate microbial contamination-related risks, to guide the microbial water quality monitoring, and to evaluate the effect of agricultural management on the microbial water quality. The Agricultural Policy/Environmental eXtender (APEX) is the watershed-scale water quality model that includes highly detailed representation of agricultural management. The APEX currently does not have microbial fate and transport simulation capabilities. The objective of this work was to develop the first APEX microbial fate and transport module that could use the APEX conceptual model of manure removal together with recently introduced conceptualizations of the in-stream microbial fate and transport. The module utilizes manure erosion rates found in the APEX. Bacteria survival in soil-manure mixing layer was simulated with the two-stage survival model. Individual survival patterns were simulated for each manure application date. Simulated in-stream microbial fate and transport processes included the reach-scale passive release of bacteria with resuspended bottom sediment during high flow events, the transport of bacteria from bottom sediment due to the hyporheic exchange during low flow periods, the deposition with settling sediment, and the two-stage survival. Default parameter values were available from recently published databases. The APEX model with the newly developed microbial fate and transport module was applied to simulate seven years of monitoring data for the Toenepi watershed in New Zealand. Based on calibration and testing results, the APEX with the microbe module reproduced well the monitored pattern of E. coli concentrations at the watershed outlet. The APEX with the microbial fate and transport module will be utilized for predicting microbial quality of water under various agricultural

  16. Remediation challenges posed by the fate and transport properties of MTBE

    International Nuclear Information System (INIS)

    Day, M.J.

    2002-01-01

    Releases of fuel from underground tank systems have been a major source of groundwater contamination for several decades. The fate and transport characteristics of fuel components significantly influence the potential risk to groundwater supplies and the methodologies to manage and remediate contamination at fuel release sites. The recognition that MTBE can be more mobile in groundwater systems than other components of oxygenated fuels has put an increased emphasis on early detection and response to fuel leaks and spills. Remediation of oxygenated fuel releases usually follows a sequence of tasks: receptor protection, source control, residual and dissolved phase remediation, and monitored natural attenuation. Good characterization of hydrogeological and geochemical conditions is required because understanding the fate and transport of fuel components is critical to developing an appropriate management plan and an efficient remediation program. Understanding the specific site conditions allows appropriate selection and sequencing of remedial technologies. The physical and chemical characteristics of MTBE can result in a higher mobility in the subsurface, compared with the BTEX components of a gasoline release. These same characteristics make MTBE more readily extractable from the subsurface compared with BTEX. There is an impression that remediating gasoline releases containing MTBE requires costly, specialized technologies compared with those employed to deal with non-oxygenated fuel releases. However, the characteristics of MTBE are well suited to traditional, physical remedial approaches that have proven to be effective with the other components of gasoline. Technologies such as groundwater extraction, soil vapor extraction (SVE), and thermal desorption work exceptionally well with MTBE due to its low adsorptive and high vapor pressure characteristics. Similarly, recent studies have demonstrated that MTBE is biodegradable under a wide variety of conditions

  17. Environmental fate and behaviour of the biocontrol agent Bacillus amyloliquefaciens CPA-8 after preharvest application to stone fruit.

    Science.gov (United States)

    Vilanova, Laura; Teixidó, Neus; Usall, Josep; Balsells-Llauradó, Marta; Gotor-Vila, Amparo; Torres, Rosario

    2018-02-01

    Bacillus amyloliquefaciens strain CPA-8 has been described as an effective biocontrol agent to control brown rot in stone fruit for both preharvest and postharvest applications. However, no information about the environmental fate and behaviour of this strain under field conditions is available. The dispersion of the CPA-8 application was evaluated using water-sensitive papers, and complete coverage was observed on the leaves of treated trees, while treatment. On non-treated trees, CPA-8 was detected on leaves until 180 days after treatment, and on weeds, the CPA-8 population was dependent on the distance from the treated trees. A high persistence of CPA-8 was detected on inert materials, such as clothes and gloves worn by handlers and plastic harvesting boxes. More than 99% of the samples with a CPA-8 phenotype were confirmed as CPA-8 using polymerase chain reaction (PCR). This work demonstrated a good distribution, persistence and adaptation of the CPA-8 strain to field and postharvest conditions. Monitoring of dispersion and persistence is an excellent tool to determine the time of application and provides valuable information for registering issues. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  18. Role of environmental factors and microorganisms in determining the fate of polycyclic aromatic hydrocarbons in the marine environment

    Science.gov (United States)

    Duran, Robert; Cravo-Laureau, Cristiana

    2016-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are widespread in marine ecosystems and originate from natural sources and anthropogenic activities. PAHs enter the marine environment in two main ways, corresponding to chronic pollution or acute pollution by oil spills. The global PAH fluxes in marine environments are controlled by the microbial degradation and the biological pump, which plays a role in particle settling and in sequestration through bioaccumulation. Due to their low water solubility and hydrophobic nature, PAHs tightly adhere to sediments leading to accumulation in coastal and deep sediments. Microbial assemblages play an important role in determining the fate of PAHs in water and sediments, supporting the functioning of biogeochemical cycles and the microbial loop. This review summarises the knowledge recently acquired in terms of both chronic and acute PAH pollution. The importance of the microbial ecology in PAH-polluted marine ecosystems is highlighted as well as the importance of gaining further in-depth knowledge of the environmental services provided by microorganisms. PMID:28201512

  19. Sorption of lipophilic organic compunds to wood and implications for their environmental fate

    DEFF Research Database (Denmark)

    Trapp, Stefan; Miglioranza, S.B.; Mosbæk, Hans

    2001-01-01

    The sorption from water to wood (KWood) of 10 organic chemicals (logKOW, 1.48-6.20) was experimentally determined for oak (Quercus robur) and basket willow (Salix viminalis). Linear regression yielded log KWood ) -0.27 (( 0.25) + 0.632 (( 0.063)log KOW for oak (r ) 0.90, n ) 27) and log KWood ) -...... time. If metabolism inside the stem occurs, wood can serve as a “safe sink” for environmental chemicals. This might be of use in phytoremediation....

  20. Fate, behaviour and toxicity of engineered nanomaterials in the environmental systems

    CSIR Research Space (South Africa)

    Musee, N

    2012-04-01

    Full Text Available ? Environmental risks of ENMs to biological organisms in the environment MUST satisfy two conditions: Hazard & Exposure ? Hazard (toxic effect): due to nano/bio interface ?interactions of ENMs with: Biomolecules, cell membranes, the cellular interior...., Langmuir, 2011, Effect of surface coating A: Unmodified AgNPs B: Modified SDS AgNPs Steric effects due to EDL, increased zeta potential and enhanced AgNPs stability DLS size measurements B: Modified Tween 80 AgNPs A: Unmodified AgNPs A: 0 ?L...

  1. The role of direct photolysis and indirect photochemistry in the environmental fate of ethylhexyl methoxy cinnamate (EHMC) in surface waters.

    Science.gov (United States)

    Vione, D; Calza, P; Galli, F; Fabbri, D; Santoro, V; Medana, C

    2015-12-15

    The aquatic environmental fate of ethylhexyl methoxy cinnamate (EHMC), one of the most used UVB filters worldwide, was studied by assessing its environmental persistence and photoinduced transformations. The role of direct and indirect photolysis was evaluated. Direct photolysis was shown to play a key role, and this process is expected to be the main attenuation route of EHMC in sunlit surface waters. In contrast, the reaction with OH radicals would be negligible and that with (3)CDOM* would at most be a secondary process. The measurement of the quantum yield of direct photolysis and of the rate constants of reaction with photogenerated transient species (or, sometimes, the use of reasonable values for the latter) allowed the prediction of the EHMC half-life time in surface waters, by means of a validated photochemical model. The predicted EHMC lifetime is of the order of hours to a few days in fair-weather summertime, and the main factors controlling the EHMC phototransformation in sunlit surface waters would be the water depth and the dissolved organic carbon (DOC) content. The formation of transformation products (TPs) was followed as well via HPLC/HRMS. Three TPs were detected in the samples exposed to UVA radiation, while one additional TP was detected in the samples exposed to UVB radiation. The detected TPs comprised 4-methoxybenzaldehyde, a hydroxylated derivative and dimeric species. Through the use of heterogeneous photocatalysis with TiO2, seven additional TPs were identified, most of them resulting from the further degradation of primary TPs formed through direct photolysis and that might be detected in aquatic systems as well. The photodegradation of EHMC in the presence of TiO2 yielded more toxic TPs than the parent compound (as determined with the Vibrio fischeri Microtox assay). The increased toxicity is partially accounted for by the formation of 4-methoxybenzaldehyde. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Environmental fate and quantitative analysis of oilsands naphthenic acids : a review

    Energy Technology Data Exchange (ETDEWEB)

    McMartin, D. [Regina Univ., SK (Canada). Faculty of Engineering; Peru, K.M.; Headley, J. [Environment Canada, Saskatoon, SK (Canada). National Water Research Inst.

    2006-07-01

    Naphthenic acids (NA) are toxic to aquatic species and mammals. Significant concentrations of NA are found in oil sands tailings ponds. This presentation reviewed some of the analytical tools used by industry and environmentalists to remediate NA. Environmental persistence results were presented, as well as detailed information regarding the origin of NA in tailings ponds. Chemistry and toxicological considerations were examined, and current analytical methods for aquatic sampling were reviewed. Issues concerning photodegradation and phytoremediation were discussed. Details of the environmental effects of NA exposure were presented. Studies investigating the microbial populations required to degrade NA in water were discussed, as well as recent research investigating the phytoremediation of wetlands exposed to NA. It was noted that research is currently being conducted to optimize algae culture for use in phytoremediation methods. However, many of the components of NA are resistant to the biodegradation, photodegradation and phytoremediation methods currently used. It was concluded that further research is needed to complete mass balance studies in riverine systems and to evaluate the cellular level toxicity of NA in plants. refs., tabs., figs.

  3. Environmental fate model for ultra-low-volume insecticide applications used for adult mosquito management

    Science.gov (United States)

    Schleier, Jerome J.; Peterson, Robert K.D.; Irvine, Kathryn M.; Marshall, Lucy M.; Weaver, David K.; Preftakes, Collin J.

    2012-01-01

    One of the more effective ways of managing high densities of adult mosquitoes that vector human and animal pathogens is ultra-low-volume (ULV) aerosol applications of insecticides. The U.S. Environmental Protection Agency uses models that are not validated for ULV insecticide applications and exposure assumptions to perform their human and ecological risk assessments. Currently, there is no validated model that can accurately predict deposition of insecticides applied using ULV technology for adult mosquito management. In addition, little is known about the deposition and drift of small droplets like those used under conditions encountered during ULV applications. The objective of this study was to perform field studies to measure environmental concentrations of insecticides and to develop a validated model to predict the deposition of ULV insecticides. The final regression model was selected by minimizing the Bayesian Information Criterion and its prediction performance was evaluated using k-fold cross validation. Density of the formulation and the density and CMD interaction coefficients were the largest in the model. The results showed that as density of the formulation decreases, deposition increases. The interaction of density and CMD showed that higher density formulations and larger droplets resulted in greater deposition. These results are supported by the aerosol physics literature. A k-fold cross validation demonstrated that the mean square error of the selected regression model is not biased, and the mean square error and mean square prediction error indicated good predictive ability.

  4. Photodegradation of antibiotics under simulated solar radiation: implications for their environmental fate.

    Science.gov (United States)

    Batchu, Sudha Rani; Panditi, Venkata R; O'Shea, Kevin E; Gardinali, Piero R

    2014-02-01

    Roxithromycin, erythromycin, ciprofloxacin and sulfamethoxazole are frequently detected antibiotics in environmental waters. Direct and indirect photolysis of these problematic antibiotics were investigated in pure and natural waters (fresh and salt water) under irradiation of different light sources. Fundamental photolysis parameters such as molar absorption coefficient, quantum yield and first order rate constants are reported and discussed. The antibiotics are degraded fastest under ultraviolet 254 nm, followed by 350 nm and simulated solar radiation. The composition of the matrix (pH, dissolved organic content, chloride ion concentration) played a significant role in the observed photodegradation. Under simulated solar radiation, ciprofloxacin and sulfamethoxazole degrade relatively quickly with half-lives of 0.5 and 1.5h, respectively. However, roxithromycin and erythromycin, macrolides are persistent (half-life: 2.4-10 days) under solar simulation. The transformation products (15) of the targeted antibiotics produced under irradiation experiments were identified using high resolution mass spectrometry and degradation pathways were proposed. © 2013.

  5. Development of Cortical GABAergic Neurons: Interplay of progenitor diversity and environmental factors on fate specification

    Directory of Open Access Journals (Sweden)

    Juliana Alves Brandão

    2015-04-01

    Full Text Available Cortical GABAergic interneurons constitute an extremely diverse population of cells organized in a well-defined topology of precisely interconnected cells. They play a crucial role regulating inhibitory-excitatory balance in brain circuits, gating sensory perception and regulating spike timing to brain oscillations during distinct behaviors. Dysfunctions in the establishment of proper inhibitory circuits have been associated to several brain disorders such as autism, epilepsy and schizophrenia. In the rodent adult cortex, inhibitory neurons are generated during the second gestational week from distinct progenitor lineages located in restricted domains of the ventral telencephalon. However, only recently, studies have revealed some of the mechanisms generating the heterogeneity of neuronal subtypes and their modes of integration in brain networks. Here we will discuss some the events involved in the production of cortical GABAergic neuron diversity with focus on the interaction between intrinsically driven genetic programs and environmental signals during development.

  6. Environmentally Persistent Free Radical (EPFRs) - Ambient Air Particulates, Soils and Fate of Some Pollutants

    Science.gov (United States)

    Lomnicki, S. M.

    2017-12-01

    Environmentally Persistent Free Radicals (EPFRs) are relatively recently discovered species that are present on ambient air particulates. Their origin is typically associated with the combustion borne PM, where in the cool zone of the combustion process aromatic precursors react with the metal centers of particulates forming surface-organic complex with radical characteristics. EPFRs have been found to be sufficiently resistant to be emitted from the combustion sources and persist in the ambient air on particulates. Their inhalation has been associated with severe health effects, and potentially are one of the major agents contributing the epidemiological risks of PM exposure. Interestingly, EPFRs can be formed not only at the elevated temperatures but also in ambient conditions, where the contact of precursor molecules with transition metal (but not only) domains can result in adsorbate complexes. In fact, EPFRs have been detected in the contaminated soils, or during the oil spill incidents. It is very likely, that the interaction of some molecules released to the air can result in the formation of EPFRs on the ambient air particulates in atmospheric conditions. These species can be a natural degradation by-products that lead to the formation of oxygenated organics in ambient atmosphere.

  7. Occurrence, control and fate of contaminants of emerging concern in environmental compartments in Brazil.

    Science.gov (United States)

    Starling, Maria Clara V M; Amorim, Camila C; Leão, Mônica Maria D

    2018-04-22

    This is the first review to present data obtained in Brazil over the years regarding contaminants of emerging concern (CEC) and to contrast it with contamination in other countries. Data gathered indicated that caffeine, paracetamol, atenolol, ibuprofen, cephalexin and bisphenol A occur in the μg L -1 range in streams near urban areas. While endocrine disruptors are frequently detected in surface waters, highest concentrations account for 17α-ethynylestradiol and 17β-estradiol. Organochlorine pesticides are the most frequently found and persistent in sediments in agricultural regions. Moreover, in tropical agricultural fields, pesticide volatilization and its implications to ecosystem protection must be better investigated. The reality represented here for Brazil may be transposed to other developing countries due to similarities related to primitive basic sanitation infrastructure and economic and social contexts, which contribute to continuous environmental contamination by CEC. Municipal wastewater treatment facilities in Brazil, treat up to the secondary stage and lead to limited CEC removal. This is also true for other nations in Latin America, such as Argentina, Colombia and Mexico. Therefore, it is an urgent priority to improve sanitation infrastructure and, then, the implementation of tertiary treatment shall be imposed. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Development and evaluation of the bacterial fate and transport module for the Agricultural Policy/Environmental eXtender (APEX) model.

    Science.gov (United States)

    Hong, Eun-Mi; Park, Yongeun; Muirhead, Richard; Jeong, Jaehak; Pachepsky, Yakov A

    2018-02-15

    The Agricultural Policy/Environmental eXtender (APEX) is a watershed-scale water quality model that includes detailed representation of agricultural management. The objective of this work was to develop a process-based model for simulating the fate and transport of manure-borne bacteria on land and in streams with the APEX model. The bacteria model utilizes manure erosion rates to estimate the amount of edge-of-field bacteria export. Bacteria survival in manure is simulated as a two-stage process separately for each manure application event. In-stream microbial fate and transport processes include bacteria release from streambeds due to sediment resuspension during high flow events, active release from the streambed sediment during low flow periods, bacteria settling with sediment, and survival. Default parameter values were selected from published databases and evaluated based on field observations. The APEX model with the newly developed microbial fate and transport module was applied to simulate fate and transport of the fecal indicator bacterium Escherichia coli in the Toenepi watershed, New Zealand that was monitored for seven years. The stream network of the watershed ran through grazing lands with daily bovine waste deposition. Results show that the APEX with the bacteria module reproduced well the monitored pattern of E. coli concentrations at the watershed outlet. The APEX with the microbial fate and transport module will be utilized for predicting microbial quality of water as affected by various agricultural practices, evaluating monitoring protocols, and supporting the selection of management practices based on regulations that rely on fecal indicator bacteria concentrations. Published by Elsevier B.V.

  9. Evaluation of biological properties and fate in the environment of a new class of biosurfactants.

    Science.gov (United States)

    Liwarska-Bizukojc, Ewa; Olejnik, Dorota; Delbeke, Elisabeth I P; Van Geem, Kevin M; Stevens, Christian V

    2018-06-01

    Selected sophorolipid quaternary ammonium salts (SQAS), being a new class of modified biosurfactants, were studied in this work for the first time with regard to their biodegradability and fate in the environment. It was made to find whether environment-friendly bioproducts like biosurfactants are still safe to the environment after their chemical modification. The susceptibility of these SQAS for biodegradation was estimated together with the evaluation of their influence on activated sludge microorganisms. Additionally, the mechanisms of removal of the SQAS from wastewater and from the aquatic environment, were analysed. The evaluated SQAS were potentially biodegradable, although none of them could be classified as readily biodegradable. The biodegradation degrees after 28 days ranged from 4 to 42%, dependent on the SQAS tested, i.e. below the required OECD 301D Closed Bottle Test level of 60%. Simultaneously, the analysis of the mass spectra revealed the presence of the breakdown products of each SQAS studied. Biodegradation was preceded by sorption of the SQAS on sludge particles, which occurred to be a main mechanism of the removal of these newly synthesized biosurfactants from wastewater. The mean degree of sorption calculated on the basis of SQAS determination was from 75 to 96%, dependent on the studied SQAS. The presence of SQAS in wastewater did not deteriorate the operation of the activated sludge system, although the products of the SQAS biodegradation remained in the liquid phase and might contribute to the increase of COD of the effluent to be introduced to the environment. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. The role of direct photolysis and indirect photochemistry in the environmental fate of ethylhexyl methoxy cinnamate (EHMC) in surface waters

    International Nuclear Information System (INIS)

    Vione, D.; Calza, P.; Galli, F.; Fabbri, D.; Santoro, V.; Medana, C.

    2015-01-01

    The aquatic environmental fate of ethylhexyl methoxy cinnamate (EHMC), one of the most used UVB filters worldwide, was studied by assessing its environmental persistence and photoinduced transformations. The role of direct and indirect photolysis was evaluated. Direct photolysis was shown to play a key role, and this process is expected to be the main attenuation route of EHMC in sunlit surface waters. In contrast, the reaction with ·OH radicals would be negligible and that with "3CDOM* would at most be a secondary process. The measurement of the quantum yield of direct photolysis and of the rate constants of reaction with photogenerated transient species (or, sometimes, the use of reasonable values for the latter) allowed the prediction of the EHMC half-life time in surface waters, by means of a validated photochemical model. The predicted EHMC lifetime is of the order of hours to a few days in fair-weather summertime, and the main factors controlling the EHMC phototransformation in sunlit surface waters would be the water depth and the dissolved organic carbon (DOC) content. The formation of transformation products (TPs) was followed as well via HPLC/HRMS. Three TPs were detected in the samples exposed to UVA radiation, while one additional TP was detected in the samples exposed to UVB radiation. The detected TPs comprised 4-methoxybenzaldehyde, a hydroxylated derivative and dimeric species. Through the use of heterogeneous photocatalysis with TiO_2, seven additional TPs were identified, most of them resulting from the further degradation of primary TPs formed through direct photolysis and that might be detected in aquatic systems as well. The photodegradation of EHMC in the presence of TiO_2 yielded more toxic TPs than the parent compound (as determined with the Vibrio fischeri Microtox assay). The increased toxicity is partially accounted for by the formation of 4-methoxybenzaldehyde. - Highlights: • Study of the photolytic and photocatalytic transformation

  11. The role of direct photolysis and indirect photochemistry in the environmental fate of ethylhexyl methoxy cinnamate (EHMC) in surface waters

    Energy Technology Data Exchange (ETDEWEB)

    Vione, D. [Department of Chemistry, University of Torino, via P. Giuria 5, 10125 Torino (Italy); Calza, P., E-mail: paola.calza@unito.it [Department of Chemistry, University of Torino, via P. Giuria 5, 10125 Torino (Italy); Galli, F.; Fabbri, D. [Department of Chemistry, University of Torino, via P. Giuria 5, 10125 Torino (Italy); Santoro, V.; Medana, C. [Department of Molecular Biotechnology and Health Sciences, University of Torino, via P. Giuria 5, 10125 Torino (Italy)

    2015-12-15

    The aquatic environmental fate of ethylhexyl methoxy cinnamate (EHMC), one of the most used UVB filters worldwide, was studied by assessing its environmental persistence and photoinduced transformations. The role of direct and indirect photolysis was evaluated. Direct photolysis was shown to play a key role, and this process is expected to be the main attenuation route of EHMC in sunlit surface waters. In contrast, the reaction with ·OH radicals would be negligible and that with {sup 3}CDOM* would at most be a secondary process. The measurement of the quantum yield of direct photolysis and of the rate constants of reaction with photogenerated transient species (or, sometimes, the use of reasonable values for the latter) allowed the prediction of the EHMC half-life time in surface waters, by means of a validated photochemical model. The predicted EHMC lifetime is of the order of hours to a few days in fair-weather summertime, and the main factors controlling the EHMC phototransformation in sunlit surface waters would be the water depth and the dissolved organic carbon (DOC) content. The formation of transformation products (TPs) was followed as well via HPLC/HRMS. Three TPs were detected in the samples exposed to UVA radiation, while one additional TP was detected in the samples exposed to UVB radiation. The detected TPs comprised 4-methoxybenzaldehyde, a hydroxylated derivative and dimeric species. Through the use of heterogeneous photocatalysis with TiO{sub 2}, seven additional TPs were identified, most of them resulting from the further degradation of primary TPs formed through direct photolysis and that might be detected in aquatic systems as well. The photodegradation of EHMC in the presence of TiO{sub 2} yielded more toxic TPs than the parent compound (as determined with the Vibrio fischeri Microtox assay). The increased toxicity is partially accounted for by the formation of 4-methoxybenzaldehyde. - Highlights: • Study of the photolytic and photocatalytic

  12. Development and evaluation of the microbial fate and transport module for the Agricultural Policy/Environmental eXtender (APEX) model

    Science.gov (United States)

    Hong, Eun-Mi; Park, Yongeun; Muirhead, Richard; Pachepsky, Yakov

    2017-04-01

    Pathogenic microorganisms in recreational and irrigation waters remain the subject of concern. Water quality models are used to estimate microbial quality of water sources, to evaluate microbial contamination-related risks, to guide the microbial water quality monitoring, and to evaluate the effect of agricultural management on the microbial water quality. The Agricultural Policy/Environmental eXtender (APEX) is the watershed-scale water quality model that includes highly detailed representation of agricultural management. The APEX currently does not have microbial fate and transport simulation capabilities. The objective of this work was to develop the first APEX microbial fate and transport module that could use the APEX conceptual model of manure removal together with recently introduced conceptualizations of the in-stream microbial fate and transport. The module utilizes manure erosion rates found in the APEX. The total number of removed bacteria was set to the concentrations of bacteria in soil-manure mixing layer and eroded manure amount. Bacteria survival in soil-manure mixing layer was simulated with the two-stage survival model. Individual survival patterns were simulated for each manure application date. Simulated in-stream microbial fate and transport processes included the reach-scale passive release of bacteria with resuspended bottom sediment during high flow events, the transport of bacteria from bottom sediment due to the hyporheic exchange during low flow periods, the deposition with settling sediment, and the two-stage survival. Default parameter values were available from recently published databases. The APEX model with the newly developed microbial fate and transport module was applied to simulate seven years of monitoring data for the Toenepi watershed in New Zealand. The stream network of the watershed ran through grazing lands with the daily bovine waste deposition. Based on calibration and testing results, the APEX with the microbe module

  13. The OECD expert meeting on ecotoxicology and environmental fate — Towards the development of improved OECD guidelines for the testing of nanomaterials

    International Nuclear Information System (INIS)

    Kühnel, Dana; Nickel, Carmen

    2014-01-01

    On behalf of the OECD Working Party on Manufactured Nanomaterials (WPMN) an expert meeting on ecotoxicology and environmental fate of nanomaterials (NMs) took place in January 2013 in Berlin. At this meeting experts from science, industry and regulatory bodies discussed the applicability of OECD test guidelines (TGs) for chemicals to nanomaterials. The objective was to discuss the current state of the relevant science and provide recommendations to the OECD WPMN on (1) the need for updating current OECD TGs and the need for developing new ones specific to nanomaterials; and (2) guidance needed for the appropriate and valid testing of environmental fate and ecotoxicity endpoints for NMs. Experts at the workshop agreed that the majority of the OECD TG for chemicals were generally applicable for the testing of NM, with the exception of TG 105 (water solubility) and 106 (adsorption-desorption). Additionally, the workshop also highlighted considerations when conducting OECD chemical TG on nanomaterials (e.g., sample preparation, dispersion, analysis, dosimetry and characterisation). These considerations will lead to the future development of proposals for new TG and guidance documents (GDs) to ensure that OECD TG give meaningful, repeatable, and accurate results when used for nanomaterials. This report provides a short overview of topics discussed during the meeting and the main outcomes. A more detailed report of the workshop will become available through the OECD, however, due to the urgency of having OECD TG relevant for nanomaterials, this brief report is being shared with the scientific community through this communication. - Highlights: • OECD test guidelines (TGs) were developed for the testing of conventional chemicals. • Need for discussion on applicability of current TGs to nanomaterials • An expert meeting addressing this issue was held. • The focus was on TGs covering ecotoxicology and environmental fate. • Recommendations for updating current OECD

  14. Environmental properties related to active galactic nuclei

    Science.gov (United States)

    Manzer, Lianne H.

    There continues to be significant controversy regarding the mechanisms responsible for the initiation of activity in galactic nuclei. It is well understood that the non-thermal energy produced by an AGN is due to accretion onto a supermassive black hole. It has not yet been determined, however, what leads particular galaxies to become active. An accurate exploration into what triggers an AGN demands an analysis of a large sample of galaxies across a diverse set of environments. In this work, we investigate possible environmental influences by carrying out a statistical investigation of galaxy groups. Using the catalogue of Yang et al. (2007), in which groups of galaxies containing between 2 and 20 members with redshifts between 0.01 -- 0.20 were taken from the Sloan Digital Sky Survey, we investigate the fraction of active galactic nuclei (AGN) within these groups and compare it to the sample of isolated galaxies also obtained from Yang et al. (2007). After correcting our spectroscopic data for extinction and underlying stellar absorption, we classify the galaxy sample using relevant emission-line ratios. We propose an alternate method for classifying emission-line galaxies, including AGN, which builds upon standard diagnostic utilities used for optical classification and includes uncertainties. Such classification probabilities offer a more robust and consistent method of investigating the effect of group environments with galaxy type. We find our sample to be a fair representation of the local universe by comparing the luminosity function of our entire data set to that of Blanton et al. (2001), Blanton et al. (2003b), and Montero-Dorta & Prada (2009). The evidence also suggests that the luminosity function of galaxies differs between isolated galaxies and galaxies in groups. We find a significant increase in the fraction of AGNs identified in grouped environments. On the other hand, we find a higher fraction of starforming galaxies within isolated systems. We

  15. Fate modelling of chemical compounds with incomplete data sets

    DEFF Research Database (Denmark)

    Birkved, Morten; Heijungs, Reinout

    2011-01-01

    Impact assessment of chemical compounds in Life Cycle Impact Assessment (LCIA) and Environmental Risk Assessment (ERA) requires a vast amount of data on the properties of the chemical compounds being assessed. These data are used in multi-media fate and exposure models, to calculate risk levels...... in an approximate way. The idea is that not all data needed in a multi-media fate and exposure model are completely independent and equally important, but that there are physical-chemical and biological relationships between sets of chemical properties. A statistical model is constructed to underpin this assumption...... and other indicators. ERA typically addresses one specific chemical, but in an LCIA, the number of chemicals encountered may be quite high, up to hundreds or thousands. This study explores the development of meta-models, which are supposed to reflect the “true”multi-media fate and exposure model...

  16. Fully in Silico Calibration of Empirical Predictive Models for Environmental Fate Properties of Novel Munitions Compounds

    Science.gov (United States)

    2016-04-01

    constants using several IMC related aromatic amines. To develop QSARs with these data, many possible descriptors were evaluated , ranging from simple to...converted to approximate half-lives to give. The blue symbols are experimental data, obtained with IMC related amino compounds...calibrated “in silico” that predict the hydrolysis behavior of the diverse range of energetic NACs. However, new experimental and computational

  17. Environmental Factors And Surface Properties Of Nanoparticles Governing Their Fate, Reactivity, And Mobility

    Science.gov (United States)

    The application of nanoparticles (NPs) for industrial processes and consumer products is rising at an exponential rate. While NPs are leading to new discoveries and improvements in our daily lives, little consideration is put forth to understand the impact of NPs in the environm...

  18. OPERA: A free and open source QSAR tool for predicting physicochemical properties and environmental fate endpoints

    Science.gov (United States)

    Collecting the chemical structures and data for necessary QSAR modeling is facilitated by available public databases and open data. However, QSAR model performance is dependent on the quality of data and modeling methodology used. This study developed robust QSAR models for physi...

  19. An overview of chemical additives present in plastics: Migration, release, fate and environmental impact during their use, disposal and recycling.

    Science.gov (United States)

    Hahladakis, John N; Velis, Costas A; Weber, Roland; Iacovidou, Eleni; Purnell, Phil

    2018-02-15

    Over the last 60 years plastics production has increased manifold, owing to their inexpensive, multipurpose, durable and lightweight nature. These characteristics have raised the demand for plastic materials that will continue to grow over the coming years. However, with increased plastic materials production, comes increased plastic material wastage creating a number of challenges, as well as opportunities to the waste management industry. The present overview highlights the waste management and pollution challenges, emphasising on the various chemical substances (known as "additives") contained in all plastic products for enhancing polymer properties and prolonging their life. Despite how useful these additives are in the functionality of polymer products, their potential to contaminate soil, air, water and food is widely documented in literature and described herein. These additives can potentially migrate and undesirably lead to human exposure via e.g. food contact materials, such as packaging. They can, also, be released from plastics during the various recycling and recovery processes and from the products produced from recyclates. Thus, sound recycling has to be performed in such a way as to ensure that emission of substances of high concern and contamination of recycled products is avoided, ensuring environmental and human health protection, at all times. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  20. Impact of surface coating and environmental conditions on the fate and transport of silver nanoparticles in the aquatic environment

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, Laura-Jayne A.; Valsami-Jones, Eugenia [School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Lead, Jamie R., E-mail: Jlead@mailbox.sc.edu [School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Center for Environmental Nanoscience and Risk (CENR), Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia 29208 (United States); Baalousha, Mohammed, E-mail: Mbaalous@mailbox.sc.edu [Center for Environmental Nanoscience and Risk (CENR), Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia 29208 (United States)

    2016-10-15

    The role of surface coating (polyvinylpyrrolidone (PVP) and citrate) and water chemistry on the fate and behavior of AgNPs in aquatic microcosms is reported in this study. The migration and transformation of the AgNPs was examined in low (ultrapure water-UPW) and high ionic strength (moderately hard water – MHW) preparations, and in the presence of modeled natural organic matter (NOM) of Suwannee River Fulvic Acid (SRFA). The migration and fate of the AgNPs in the microcosms was validated using a sedimentation-diffusion model and the aggregation behavior was monitored by UV–visible spectrometry (UV–vis). Dissolved and particulate Ag concentrations (% Ag) were analyzed by ultrafiltration methods. Imaging of the AgNPs was captured using transmission electron microscopy (TEM). Results indicate that PVP-coated AgNPs (PVP-AgNPs) remained stable for 28 days with similarly distributed concentrations of the PVP-AgNPs throughout the columns in each of the water conditions after approximately 96 h (4 days). The sedimentation-diffusion model confirmed PVP-AgNP stability in each condition, by showing diffusion dominated transport by using the original unaltered AgNP sizes to fit the parameters. In comparison, citrate AgNPs were largely unstable in the more complex water preparations (MHW). In MHW, aggregation dominated behavior followed by sedimentation/dissolution controlled transport was observed. The addition of SRFA to MHW resulted in small stabilizing effects, to the citrate coated AgNPs, producing smaller sized AgNPs (TEM) and mixed sedimentation and diffusion migration compared the studies absent of SRFA. The results suggest that surface coating and solution chemistry has a major impact on AgNP stability, furthermore the corresponding modeling will support the experimental understanding of the overall fate of AgNPs in the environment. - Highlights: • Aquatic microcosms were used to study the transport and behavior of AgNPs • Experiments were conducted in low

  1. Impact of surface coating and environmental conditions on the fate and transport of silver nanoparticles in the aquatic environment

    International Nuclear Information System (INIS)

    Ellis, Laura-Jayne A.; Valsami-Jones, Eugenia; Lead, Jamie R.; Baalousha, Mohammed

    2016-01-01

    The role of surface coating (polyvinylpyrrolidone (PVP) and citrate) and water chemistry on the fate and behavior of AgNPs in aquatic microcosms is reported in this study. The migration and transformation of the AgNPs was examined in low (ultrapure water-UPW) and high ionic strength (moderately hard water – MHW) preparations, and in the presence of modeled natural organic matter (NOM) of Suwannee River Fulvic Acid (SRFA). The migration and fate of the AgNPs in the microcosms was validated using a sedimentation-diffusion model and the aggregation behavior was monitored by UV–visible spectrometry (UV–vis). Dissolved and particulate Ag concentrations (% Ag) were analyzed by ultrafiltration methods. Imaging of the AgNPs was captured using transmission electron microscopy (TEM). Results indicate that PVP-coated AgNPs (PVP-AgNPs) remained stable for 28 days with similarly distributed concentrations of the PVP-AgNPs throughout the columns in each of the water conditions after approximately 96 h (4 days). The sedimentation-diffusion model confirmed PVP-AgNP stability in each condition, by showing diffusion dominated transport by using the original unaltered AgNP sizes to fit the parameters. In comparison, citrate AgNPs were largely unstable in the more complex water preparations (MHW). In MHW, aggregation dominated behavior followed by sedimentation/dissolution controlled transport was observed. The addition of SRFA to MHW resulted in small stabilizing effects, to the citrate coated AgNPs, producing smaller sized AgNPs (TEM) and mixed sedimentation and diffusion migration compared the studies absent of SRFA. The results suggest that surface coating and solution chemistry has a major impact on AgNP stability, furthermore the corresponding modeling will support the experimental understanding of the overall fate of AgNPs in the environment. - Highlights: • Aquatic microcosms were used to study the transport and behavior of AgNPs • Experiments were conducted in low

  2. ENVIRONMENTAL EFFECTS OF ABANDONED PROPERTIES IN ...

    African Journals Online (AJOL)

    Osondu

    Effects observed include pollution, health problem, city's financial loss, obscenity, crime, property value decline, ... fundamental preoccupation of planning for public purpose; is to ... are found with slum characteristics. ... Results and Discussion.

  3. Ethical perspectives on the environmental impact of property ...

    African Journals Online (AJOL)

    What perspectives on environmental concerns exist in philosophical literature? Do these perspectives have implications for ethical property development? What are ...... implications for business ethics', PhD thesis, Department of Philosophy,.

  4. The OECD expert meeting on ecotoxicology and environmental fate--towards the development of improved OECD guidelines for the testing of nanomaterials.

    Science.gov (United States)

    Kühnel, Dana; Nickel, Carmen

    2014-02-15

    On behalf of the OECD Working Party on Manufactured Nanomaterials (WPMN) an expert meeting on ecotoxicology and environmental fate of nanomaterials (NMs) took place in January 2013 in Berlin. At this meeting experts from science, industry and regulatory bodies discussed the applicability of OECD test guidelines (TGs) for chemicals to nanomaterials. The objective was to discuss the current state of the relevant science and provide recommendations to the OECD WPMN on (1) the need for updating current OECD TGs and the need for developing new ones specific to nanomaterials; and (2) guidance needed for the appropriate and valid testing of environmental fate and ecotoxicity endpoints for NMs. Experts at the workshop agreed that the majority of the OECD TG for chemicals were generally applicable for the testing of NM, with the exception of TG 105 (water solubility) and 106 (adsorption-desorption). Additionally, the workshop also highlighted considerations when conducting OECD chemical TG on nanomaterials (e.g., sample preparation, dispersion, analysis, dosimetry and characterisation). These considerations will lead to the future development of proposals for new TG and guidance documents (GDs) to ensure that OECD TG give meaningful, repeatable, and accurate results when used for nanomaterials. This report provides a short overview of topics discussed during the meeting and the main outcomes. A more detailed report of the workshop will become available through the OECD, however, due to the urgency of having OECD TG relevant for nanomaterials, this brief report is being shared with the scientific community through this communication. Copyright © 2013. Published by Elsevier B.V.

  5. Environmental Reporting and Disclosure Practices - In Malaysian Property Industry

    OpenAIRE

    Natthondan, Shankari

    2009-01-01

    This research examined and analyzed the extent of environmental reporting and disclosure practices of the Kuala Lumpur Composite Index Companies (KLCI) as listed on the Bursa Malaysia on 21 January 2008. In particular the property industry companies were identified as a high profile sector as it is more sensitively exposed to environmental activities. The degree of reporting on environmental matters by this category of listed companies is indicative of the trend of the overall compliance and ...

  6. The Possibility of Deduction of Environmental Liabilities in Expropriation for Each Breach of Environmental Rural Property

    Directory of Open Access Journals (Sweden)

    Ricardo Nasser Sefer

    2016-10-01

    Full Text Available This study aims to address the deductibility of environmental liability indemnification of quantum measured in the expropriation of rural property that failed to fulfill its environmental function. The Federal Constitution of 1988, provided for the possibility to expropriate rural property that failed to comply with its social and environmental role. On the subject, the Federal Regional Court of the 1st Region does not signed a single position on this opportunity to deduct the environmental liability, generating as a result, legal uncertainty for landowners and the community itself, being the Institute of Colonization and Agrarian Reform - INCRA the correct deduction.

  7. Environmental effects on properties of structural alloys

    International Nuclear Information System (INIS)

    Chopra, O.K.; Smith, D.L.

    1984-01-01

    Corrosion data are presented for several austenitic and ferritic steels exposed at temperatures between 700 and 755 K in flowing lithium and Pb-17Li environments. The results indicate that dissolution rates for both steels are an order of magnitude greater in Pb-Li than in lithium. Tensile data for cold-worked type 316 stainless steel show that a flowing environment has no effect on the tensile properties of type 316 stainless steel at temperatures between 473 and 773 K

  8. Environmental Fate and Transport of Poly- and Perfluoroalkyl Substances at Aqueous Film-Forming Foam Impacted Sites

    Science.gov (United States)

    Higgins, C.

    2017-12-01

    Poly and perfluoroalkyl substances (PFASs) are constituents in aqueous film-forming foam (AFFF) used to extinguish fuel fires. Substantially elevated PFAS groundwater concentrations have been observed at firefighter protection training areas, where co-contaminants such as chlorinated solvents and fuel hydrocarbons are also commonly present. Research into the fate and transport potential of PFASs at AFFF-impacted sites will be presented, with a particular focus on how co-contaminants and co-contaminant remediation technologies may alter the composition and transport behavior of PFASs at these sites. A detailed analysis of data collected from a U.S. Air Force site (Ellsworth Air Force Base, South Dakota) indicates that that conversion of polyfluoroalkyl chemicals to perfluoroalkyl acids (PFAAs) in situ due to natural and enhanced remediation of petroleum hydrocarbons. In addition, bench-scale studies examining the effects of various chemical oxidants, typically employed via in situ chemical oxidation (ISCO), indicates that oxidation-based remediation technologies have the potential to alter the release and composition of PFASs in AFFF-impacted source zones. Future challenges in addressing PFAS contamination will be discussed, particularly with respect to closing the mass balance on PFAAs and their precursors at AFFF-impacted sites.

  9. The Property Right and the Requirements of Environmental Protection

    Directory of Open Access Journals (Sweden)

    Vasilica NEGRUŢ

    2014-11-01

    Full Text Available The environmental protection has lately become an essential component of the concept of sustainable development, along with the economic, social and cultural components. Being an objective of public interest, the environmental protection and conservation are essential to ensure the habitat necessary for continuing the human existence. Considering this aspect, the limitation of ownership required by certain laws has both a social and moral justification, the environmental protection having a direct link with the level of public health, which is a value of national interest. The legal limits of the ownership are restrictions brought by the law, considering aspects regarding the general interest of society. In this article we intend to emphasize, on the analysis and comparison of legislation and case law, the nature of the relationship between ownership of property and environmental rights, as well as the limitations of property rights in favor of environmental protection. As a conclusion, the environmental easements meet a wide national and international recognition and guarantee, the holder of the property having to exercise it in the interest of the whole community, including the protection and conservation of the environment. At the same time, we must consider that the right to property and environment are fundamental rights guaranteed by the Romanian Constitution itself, which makes us conclude that they converge and mutually enrich across the fundamental duties as well.

  10. The influence of global climate change on the environmental fate of persistent organic pollutants: A review with emphasis on the Northern Hemisphere and the Arctic as a receptor

    Science.gov (United States)

    Ma, Jianmin; Hung, Hayley; Macdonald, Robie W.

    2016-11-01

    Following worldwide bans and restrictions on the use of many persistent organic pollutants (POPs) from the late 1970s, their regional and global distributions have become governed increasingly by phase partitioning between environmental reservoirs, such as air, water, soil, vegetation and ice, where POPs accumulated during the original applications. Presently, further transport occurs within the atmospheric and aquatic reservoirs. Increasing temperatures provide thermodynamic forcing to drive these chemicals out of reservoirs, like soil, vegetation, water and ice, and into the atmosphere where they can be transported rapidly by winds and then recycled among environmental media to reach locations where lower temperatures prevail (e.g., polar regions and high elevations). Global climate change, widely considered as global warming, is also manifested by changes in hydrological systems and in the cryosphere; with the latter now exhibiting widespread loss of ice cover on the Arctic Ocean and thawing of permafrost. All of these changes alter the cycling and fate of POPs. There is abundant evidence from observations and modeling showing that climate variation has an effect on POPs levels in biotic and abiotic environments. This article reviews recent progress in research on the effects of climate change on POPs with the intention of promoting awareness of the importance of interactions between climate and POPs in the geophysical and ecological systems.

  11. Pesticide Environmental Fate Research for the 21st Century: Building Bridges Between Laboratory and Field Studies at Varying Scales

    Science.gov (United States)

    Accurate determination of predicted environmental concentrations (PECs) is a continuing and often elusive goal of pesticide risk assessment. PECs are typically derived using simulation models that depend on laboratory generated data for key input parameters (t1/2, Koc, etc.). Model flexibility in ...

  12. Marble wastes and pig slurry improve the environmental and plant-relevant properties of mine tailings.

    Science.gov (United States)

    Kabas, S; Faz, A; Acosta, J A; Arocena, J M; Zornoza, R; Martínez-Martínez, S; Carmona, D M

    2014-02-01

    Poor soil fertility is often the biggest challenge to the establishment of vegetation in mine wastes deposits. We conducted field trials in the El Gorguel and El Lirio sites in SE Spain, two representative tailing ponds of similar properties except for pH, to understand the environmental and plant-relevant benefits of marble waste (MW) and pig slurry (PS) applications to mine tailings. Low pH (5.4) tailings (El Lirio) exhibit reduction of up to fourfold in bio-availability of metals as shown by the DTPA-Zn, Pb, water-soluble Zn, Pb and up to 3× for water-soluble Cd. Tailings in El Gorguel have high pH (7.4) and did not exhibit significant trends in the reductions of water-extractable Zn, Pb, Cd and Cu. Improvements to the edaphic (plant-relevant) properties of tailings after the amendments are not as sensitive to pH compared to the environmental characteristics. The two sites had increases in aggregate stability, organic matter (total N and organic C) although total N is higher in the El Gorguel (up to 212 μg N kg(-1)) than the El Lirio (up to 26 μg N kg(-1)). However, cation exchange capacities are similar in both sites at 15.2 cmol(+) kg(-1). We conclude that the characteristics, especially pH, of tailing materials significantly influence the fate of metals but not improvements to plant-relevant properties such as cation exchange capacity and aggregate stability 1 year after the application of MW and PS amendments.

  13. Environmental Effects of Abandoned Properties in Ogbomoso and ...

    African Journals Online (AJOL)

    ... reptiles, accident and vagrancy. The brunt of abandonment is found to be more in the medium residential density. The study thus recommends an aggressive environmental management that offsets blighted conditions in the environment. Keywords: Effects, Buildings, Lots, Abandonment, Landed Properties, Environment ...

  14. Fate of linear alkylbenzenes and benzothiazoles of anthropogenic origin and their potential as environmental molecular markers in the Pearl River Delta, South China

    International Nuclear Information System (INIS)

    Ni Honggang; Shen Rulang; Zeng Hui; Zeng, Eddy Y.

    2009-01-01

    The mass emissions of linear alkylbenzenes (LABs), benzothiazole (BT), and 2-[4-morpholinyl]benzothiazole (24MoBT) from anthropogenic activities within one year were estimated according to the population and the number of automobiles in the Pearl River Delta (PRD), South China. Based on the estimation, the distribution of these compounds among various environmental media was simulated with a mass balance box model established in the present study. The results showed that 79% of LABs generated in the PRD was stored in sediment while only 1.3% of LABs was presumably transported to the adjacent South China Sea (SCS). On the contrary, 47% of BT and 77% of 24MoBT generated in the region were carried with riverine runoff to the coastal ocean. The results from the present study suggest that hydrophobic compounds tend to stay in the watershed of the PRD, whereas hydrophilic ones mainly outflow to the coastal ocean. - A simple mass balance box model examines the fate of linear alkylbenzenes and benzothiazoles in the Pearl River Delta, South China.

  15. Organochlorine pesticides and polychlorinated biphenyls in riverine runoff of the Pearl River Delta, China: Assessment of mass loading, input source and environmental fate

    International Nuclear Information System (INIS)

    Guan Yufeng; Wang Jizhong; Ni Honggang; Zeng, Eddy Y.

    2009-01-01

    A large-scale sampling program was conducted to simultaneously collect water samples at the eight major riverine runoff outlets of the Pearl River Delta (PRD), South China to assess the importance of riverine runoff in transporting anthropogenic pollutants from terrestrial sources to the coastal ocean. The concentrations of Σ 21 OCPs (sum of 21 OCP components) and Σ 20 PCBs (sum of 20 PCB congeners) were 2.57-41.2 and 0.12-1.47 ng/L, respectively. Compositional distributions of DDTs suggested the possibility of new input sources in the study area, but contributions from dicofol seemed considerably low. The annual inputs of Σ 21 OCPs and Σ 20 PCBs were 3090 and 215 kg, with those of total HCHs and DDTs being 1110 and 1020 kg, respectively. A mass balance consideration indicated that riverine runoff is the major mode carrying OCPs from the PRD to the coastal ocean, and the majority of OCPs is further dissipated to open seas. - Mass loadings, input sources and environmental fate of organochlorine pesticides and polychlorinated biphenyls in riverine runoff of the Pearl River Delta, China are assessed

  16. Degradation of Fluorotelomer-Based Polymers Contributes to the Global Occurrence of Fluorotelomer Alcohol and Perfluoroalkyl Carboxylates: A Combined Dynamic Substance Flow and Environmental Fate Modeling Analysis.

    Science.gov (United States)

    Li, Li; Liu, Jianguo; Hu, Jianxin; Wania, Frank

    2017-04-18

    Using coupled dynamic substance flow and environmental fate models, CiP-CAFE and BETR-Global, we investigated whether the degradation of side-chain fluorotelomer-based polymers (FTPs), mostly in waste stocks (i.e., landfills and dumps), serves as a long-term source of fluorotelomer alcohols (FTOHs) and perfluoroalkyl carboxylates (PFCAs) to the global environment. The modeling results indicate that, in the wake of the worldwide transition from long-chain to short-chain products, in-use stocks of C8 FTPs will peak and decline afterward, while the in-use stocks of C6 FTPs, and the waste stocks of both FTPs will generally grow. FTP degradation in waste stocks is making an increasing contribution to FTOH generation, the bulk of which readily migrates from waste stocks and degrades into PFCAs in the environment; the remaining part of the generated FTOHs degrade in waste stocks, which makes those stocks reservoirs that slowly release PFCAs into the environment over the long run because of the low leaching rate and extreme persistence of PFCAs. Short-chain FTPs have higher relative release rates of PFCAs from waste stocks than long-chain ones. Estimates of in-use and waste stocks of FTPs were more sensitive to the selected lifespan of finished products, while those of the emissions of FTOHs and PFCAs were more sensitive to the degradation half-life of FTPs in waste stocks. Our preliminary calculations highlight the need for environmentally sound management of obsolete FTP-containing products into the foreseeable future.

  17. Short- and medium-chain chlorinated paraffins in air and soil of subtropical terrestrial environment in the pearl river delta, South China: distribution, composition, atmospheric deposition fluxes, and environmental fate.

    Science.gov (United States)

    Wang, Yan; Li, Jun; Cheng, Zhineng; Li, Qilu; Pan, Xiaohui; Zhang, Ruijie; Liu, Di; Luo, Chunling; Liu, Xiang; Katsoyiannis, Athanasios; Zhang, Gan

    2013-03-19

    Research on the environmental fate of short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) in highly industrialized subtropical areas is still scarce. Air, soil, and atmospheric deposition process in the Pearl River Delta of South China were investigated, and the average SCCP and MCCP concentrations were 5.2 μg/sampler (17.69 ng/m(3)) and 4.1 μg/sampler for passive air samples, 18.3 and 59.3 ng/g for soil samples, and 5.0 and 5.3 μg/(m(2)d) for deposition samples, respectively. Influenced by primary sources and the properties of chlorinated paraffins (CPs), a gradient trend of concentrations and a fractionation of composition from more to less industrialized areas were discovered. Intense seasonal variations with high levels in summer air and winter deposition samples indicated that the air and deposition CP levels were controlled mainly by the vapor and particle phase, respectively. Complex environmental processes like volatilization and fractionation resulted in different CP profiles in different environment matrixes and sampling locations, with C(10-11) C(l6-7) and C(14) C(l6-7), C(10-12) C(l6-7) and C(14) C(l6-8), and C(11-12) C(l6-8) and C(14) C(l7-8) dominating in air, soil, and atmospheric deposition, respectively. Shorter-chain and less chlorinated congeners were enriched in air in the less industrialized areas, while longer-chain and higher chlorinated congeners were concentrated in soil in the more industrialized areas. This is suggesting that the gaseous transport of CPs is the dominant mechanism responsible for the higher concentrations of lighter and likely more mobile CPs in the rural areas.

  18. The environmental behavior and chemical fate of energetic compounds (TNT, RDX, tetryl) in soil and plant systems

    International Nuclear Information System (INIS)

    Cataldo, D.A.; Harvey, S.D.; Fellows, R.J.

    1993-06-01

    Munitions materials can accumulate or cycle in terrestrial environs at production and manufacturing facilities and thus pose potential heath and environmental concerns. To address questions related to food chain accumulation, the environmental behavior of energetic compounds (2,4,6-trinitrotoluene,TNT; hexahydro-1,3,5-trinitro-1,3,5-triazine, RDX; 2,4,6-trinitrophenylmethylnitramine, tetryl) was evaluated. Emphasis was placed on determining the potential for soil/plant transfer of munitions residues, translocation and distribution within the plant, the extent to which compounds were metabolized following accumulation, and the chemical nature and form of accumulated residues. Both TNT and tetryl undergo extensive chemical transformation in soil, forming aminodinitrotoluene isomers and N-methyl-2,4,6-trinitroaniline residues, respectively, along with a series of unknowns. After 60 days, only 30% of the amended TNT and 8% of the amended tetryl remained unchanged in the soil. In contrast, 78% of the soil-amended RDX remained unchanged after 60 days. After 60 days, plants grown in soils containing 10 ppm residues contained from 5 μg TNT/g to 600 μg RDX/G fresh wt. tissue. TNT and tetryl residues were primarily accumulated in roots (75%), while RDX was concentrated in leaves and seed. The principal transport form for TNT (root to shoot) was an acid labile conjugate of aminodinitrotoluene; RDX was transported unchanged. On accumulation in roots and leaves, highly polar and non-extractable TNT metabolites dominated, with the aminodinitrotoluene isomers accounting for less than 20% of the residues present. Only a few percent were present as the parent TNT. RDX was partitioned similarly to TNT, with 8 to 30% of the RDX appearing as polar metabolites, 20--50% as parent RDX, and the balance as non-extractable residues. Tetryl was metabolized to N-methyl-2,4,6-trinitroaniline and a variety of polar metabolites

  19. Polybrominated diphenyl ethers fate in China: a review with an emphasis on environmental contamination levels, human exposure and regulation.

    Science.gov (United States)

    Chen, Yuan; Li, Jinhui; Liu, Lili; Zhao, Nana

    2012-12-30

    Because of their highly effective flame-retardant capability, polybrominated diphenyl ethers (PBDEs) have been extensively used as flame retardants in consumer goods. However, compelling evidence shows that many congeners of PBDEs have been accumulating in the environment, in biota and in human populations worldwide. In China, although octabrominated diphenyl ether (octaBDE) has never been produced or used, pentabrominated diphenyl ether (pentaBDE) and decabrominated diphenyl ether (decaBDE) have been produced and used in large quantities. In the face of increasing evidence about PBDE pollution and the adoption of international conventions, there is a growing push for China to develop more stringent methods of managing PBDE waste. This paper summarizes the information about PBDE production and application, describes the flame-retarding mechanism, and then reviews the toxicity and levels of PBDEs in China's environmental media and human tissues. Based on international regulations on PBDEs, the paper finally puts forward some suggestions for Chinese policy making and for self-regulation within the flame retardant industry. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Toxicological Impacts of Pharmaceuticals and Personal Care Products on Water Quality: Environmental Fate, Transformation and Health Effects

    Science.gov (United States)

    Rubasinghege, G. R. S.; Rijal, H.; Gurung, R.; Maldonado-Torres, S.; Rogelj, S.; Piyasena, M.

    2016-12-01

    The growing medical and personal needs of the human population have escalated release of pharmaceuticals and personal care products (PPCPs) to the nature. The current work investigated abiotic degradation pathways of selected PPCPs in the presence of major mineral components of soil and the acute health effects of degraded PPCPs. Degradation of selected PPCPs (ibuprofen and clofibric acid) was carried out using custom-built glass reactors in batch studies. The secondary products of PPCPs were analyzed and identified using modified HPLC and LC-MS methods. Results from these studies showed that the extent of degradation depends on the type of the clay or mineral oxide, and solar radiation. In the absence of solar radiation (night time chemistry), the dominant reaction mechanism was observed to be the adsorption of PPCPs on to clay particles where surface functional groups and particle size play a key role. In contrast, under solar radiation, PPCPs break down to several fractions in the presence of clay particles. The decay rates were at least 3-fold higher for irradiated samples compared to that of dark conditions. Acute toxicity of selected PPCPs and their degradation products were tested on three microorganisms: gram-positive soil bacteria, Bacillus megaterium; gram-negative marine bacteria, Pseudoaltermonas atlantica; and algae from the Chlorella genus. Growth inhibition was measured using optical density measurements, MTT viability assay, and flow cytometer. The results suggest that the concentrations of primary compounds, Ibuprofen and Clofibric Acid, found in the environment that ranges from μg/L to ng/L are not sufficient to inhibit growth of either three microorganisms. However, selected organisms showed significant differences in sensitivity to degraded products. Results from current work advance our knowledge and understanding in the fields of environmental toxicology, chemistry in aqueous phases, and geochemistry.

  1. Ethical perspectives on the environmental impact of property development

    Directory of Open Access Journals (Sweden)

    A. Sentle Mokori

    2016-08-01

    Full Text Available Three perspectives that can be found in ethical decision-making are explored to suggest guidelines for ethical property development: the instrumental, the intrinsic and the pluralist perspective. Given the limitations of the instrumental and the intrinsic perspectives, it is suggested that the appropriate perspective to be adopted by ethical property developers is that of pragmatism, as being a system of moral pluralism. This perspective can be utilised as a flexible toolbox which unites both traditional ethical values and the diversity of environmental ethics, as well as allowing new values to emerge without adhering to relativism.

  2. Environmental importance, composition and properties of pervious concrete

    Directory of Open Access Journals (Sweden)

    Topličić-Ćurčić Gordana

    2016-01-01

    Full Text Available Porous or pervious concrete was in use since the 60's of the previous century. It was first used in the USA and afterwards in Europe. The environmental importance of pervious concrete can be seen through fast collection of stormwater from the pavements, parking lots and other impervious surfaces. . Special purification systems remove the detrimental matter from the collected strormwater. As such, it can be used for other purposes. The pervious concrete has little or almost no fine aggregates. Its porosity is high, and ranges between 15 and 30 % in comparison to the concrete volume. Prior to massive usage of pervious concrete, it was necessary to prove, i.e. to examine its properties in service conditions. The paper elucidates the environmental character of pervious concrete, provides its usual composition and its properties.

  3. Assessing the environmental fate of selected polybrominated diphenyl ethers in the region surrounding the Zhuoshui River of Taiwan based on an Equilibrium Constant fugacity model

    Science.gov (United States)

    O'Driscoll, Kieran; Doherty, Rory; Robinson, Jill; Chiang, Wen-Son; Kao Kao, Ruey-Chy

    2015-04-01

    Polybrominated diphenyl ethers (PBDEs) are a group of flame retardants that have been in use since the 1970s. They are included in the list of hazardous substances known as persistent organic pollutants (POPs) because they are extremely hazardous to the environment and human health. PBDEs have been extensively used in industry and manufacturing in Taiwan, thus its citizens are at high risk of exposure to these chemicals. An assessment of the environmental fate of these compounds in the Zhuoshui river and Changhua County regions of western Taiwan, and also including the adjacent area of the Taiwan Strait, was conducted for three high risk congeners, BDE-47, -99 and -209, to obtain information regarding the partitioning, advection, transfer and long range transport potential of the PBDEs in order to identify the level of risk posed by the pollutants in this region. The results indicate that large amounts of PBDEs presently reside in all model compartments - air, soil, water, and sediment - with particularly high levels found in air and especially in sediment. The high levels found in sediment, particularly for BDE-209, are significant, since there is the threat of these pollutants entering the food chain, either directly through benthic feeding, or through resuspension and subsequent feeding in the pelagic region of the water column which is a distinct possibility in the strong currents found within the Taiwan Strait. Another important result is that a substantial portion of emissions leave the model domain directly through advection, particularly for BDE-47 (58%) and BDE-209 (75%), thus posing a risk to adjacent communities. Model results were generally in reasonable agreement with available measured concentrations. In air, model concentrations are in reasonably good agreement with available measured values. For both BDE-47 and -99, model concentrations are a factor of 2-3 higher and BDE-209 within the range of measured values. In soil, model results are somewhat

  4. Recycled aggregates in concrete production: engineering properties and environmental impact

    Directory of Open Access Journals (Sweden)

    Seddik Meddah Mohammed

    2017-01-01

    Full Text Available Recycled concrete aggregate is considered as the most abundant and used secondary aggregate in concrete production, other types of solid waste are also being used in concrete for specific purposes and to achieve some desired properties. Recycled aggregates and particularly, recycled concrete aggregate substantially affect the properties and mix design of concrete both at fresh and hardened states since it is known by high porosity due to the adhered layer of old mortar on the aggregate which results in a high water absorption of the recycled secondary aggregate. This leads to lower density and strength, and other durability related properties. The use of most recycled aggregate in concrete structures is still limited to low strength and non-structural applications due to important drop in strength and durability performances generated. Embedding recycled aggregates in concrete is now a current practice in many countries to enhance sustainability of concrete industry and reduce its environmental impacts. The present paper discusses the various possible recycled aggregates used in concrete production, their effect on both fresh and hardened properties as well as durability performances. The economic and environmental impacts of partially or fully substituting natural aggregates by secondary recycled aggregates are also discussed.

  5. Modeling the Environmental Fate of Graphene Oxide and Its Phototransformation Products in Brier Creek Watershed Using the Water Quality Analysis Simulation Program 8 (WASP8)

    Science.gov (United States)

    Han, Y.; Bouchard, D.; Chang, X.; Hsieh, H. S.; Knightes, C. D.; Spear, J.; Zepp, R. G.

    2017-12-01

    The production of graphene-family nanoparticles (GFNs) appreciably increased in recent years. Among GFNs, graphene oxide (GO) is one of the most highly studied members due to its inexpensive synthesis cost compared to graphene, its stability in aqueous media and its broad application. However, GO also has been found to be the most toxic among GFNs. Lab studies showed that GO undergoes phototransformation in surface waters, resulting in products that include reduced GO (rGO) and polycyclic aromatic hydrocarbons (PAHs). Due to technical and analytical limitations, it is still difficult to conduct in-situ measurement of GO and rGO concentrations released in the environment, and it is of utmost importance to establish a model that can predict their environmental exposure concentrations in the environment. In this study, we develop a fate and transport model to predict time-dependent environmental exposure concentrations of GO for the Brier Creek Watershed in the GA coastal plain. We investigate the influence of sunlight radiation on the distribution of GO and its phototransformation products in the watershed over a 20-year period using the most updated Water Quality Analysis Simulation Program (WASP8). Flow rate, sediment transport data and sunlight radiation data are input into WASP8, and WASP8 is used to internally calculate a GO phototransformation rate and productions of rGO and PAHs. Heteroaggregation coefficients of GO and rGO with suspended solids were measured in an EPA laboratory, and then input into WASP8. GO and rGO concentrations in the watershed are calculated by WASP8. Mass fraction results show that GO is the predominant species among GO derived species, which account for 99% of the mass throughout the whole watershed of interest, while rGO species, including free rGO and rGO heteroaggregated to suspended solids, only account for 1%. We also found that almost all free GO and rGO are present in water column due to their extremely low settling velocity. r

  6. Solar Sail Material Performance Property Response to Space Environmental Effects

    Science.gov (United States)

    Edwards, David L.; Semmel, Charles; Hovater, Mary; Nehls, Mary; Gray, Perry; Hubbs, Whitney; Wertz, George

    2004-01-01

    The National Aeronautics and Space Administration's (NASA) Marshall Space Flight Center (MSFC) continues research into the utilization of photonic materials for spacecraft propulsion. Spacecraft propulsion, using photonic materials, will be achieved using a solar sail. A solar sail operates on the principle that photons, originating from the sun, impart pressure to the sail and therefore provide a source for spacecraft propulsion. The pressure imparted to a solar sail can be increased, up to a factor of two, if the sun-facing surface is perfectly reflective. Therefore, these solar sails are generally composed of a highly reflective metallic sun-facing layer, a thin polymeric substrate and occasionally a highly emissive back surface. Near term solar sail propelled science missions are targeting the Lagrange point 1 (Ll) as well as locations sunward of L1 as destinations. These near term missions include the Solar Polar Imager and the L1 Diamond. The Environmental Effects Group at NASA s Marshall Space Flight Center (MSFC) continues to actively characterize solar sail material in preparation for these near term solar sail missions. Previous investigations indicated that space environmental effects on sail material thermo-optical properties were minimal and would not significantly affect the propulsion efficiency of the sail. These investigations also indicated that the sail material mechanical stability degrades with increasing radiation exposure. This paper will further quantify the effect of space environmental exposure on the mechanical properties of candidate sail materials. Candidate sail materials for these missions include Aluminum coated Mylar[TM], Teonex[TM], and CPl (Colorless Polyimide). These materials were subjected to uniform radiation doses of electrons and protons in individual exposures sequences. Dose values ranged from 100 Mrads to over 5 Grads. The engineering performance property responses of thermo-optical and mechanical properties were

  7. Les hydrocarbures aromatiques polycycliques dans l'environnement. Première partie. Propriété, origines, devenir Polycyclic Aromatic Hydrocarbons in the Environment. Part One. Properties, Origins, Fates

    Directory of Open Access Journals (Sweden)

    Bouchez M.

    2006-11-01

    Full Text Available Les hydrocarbures aromatiques polycycliques (HAP sont des contaminants produits notamment dans les processus de combustion. Leur caractère ubiquiste et leur génotoxicité sont à l'origine d'une activité de recherche importante. Après avoir présenté les structures chimiques et les propriétés physico-chimiques et biologiques principales de ces composés, on résume les connaissances actuelles concernant leur présence dans l'environnement. Les critères géochimiques de leurs différentes origines pyrolytique, diagénétique ou pétrolière, sont exposés. On examine la contribution des différentes sources d'émission, le transport et la diffusion dans l'environnement de ces composés, ainsi que les modifications qu'ils subissent et leur sort ultime. La distribution qualitative et quantitative des HAP de combustion dans les sols d'environnements variés est présentée. Polycyclic aromatic hydrocarbons (PAH are environmental contaminants produced in particular in combustion processes. As a consequence of their genotoxicity and ubiquity, they are the subject of an important research activity. After a presentation of the chemical structures and of the main physico-chemical and biological properties of these compounds, the current knowledge regarding their presence in the environment is summarized. The geochernical criteria of the different,origins, pyrolytic, diagenetic and petroleum of PAH are presented. The respective contributions of their various emission sources are discussed , as well as the transfer and diffusion in the environment, the modifications undergone and the ultimate fate of these compounds. The qualitative and quantitative distribution of combustion PAH in soils in different environmental situations is presented.

  8. Optical And Environmental Properties Of NCAP Glazing Products

    Science.gov (United States)

    van Konynenburg, Peter; Wipfler, Richard T.; Smith, Jerry L.

    1989-07-01

    The first large area, commercially available, electrically-controllable glazing products sold under the tradename VARILITETM are based on a new liquid crystal film technology called NCAP. The glazing products can be switched in milliseconds between a highly translucent state (for privacy and glare control) to a transparent state (for high visibility) with the application of an AC voltage. The optical and environmental properties are demonstrated to meet the general requirements for architectural glazing use. The first qualified indoor product is described in detail.

  9. Biochar physico-chemical properties as affected by environmental exposure

    International Nuclear Information System (INIS)

    Sorrenti, Giovambattista; Masiello, Caroline A.; Dugan, Brandon; Toselli, Moreno

    2016-01-01

    To best use biochar as a sustainable soil management and carbon (C) sequestration technique, we must understand the effect of environmental exposure on its physical and chemical properties because they likely vary with time. These properties play an important role in biochar's environmental behavior and delivery of ecosystem services. We measured biochar before amendment and four years after amendment to a commercial nectarine orchard at rates of 5, 15 and 30 t ha −1 . We combined two pycnometry techniques to measure skeletal (ρ s ) and envelope (ρ e ) density and to estimate the total pore volume of biochar particles. We also examined imbibition, which can provide information about soil hydraulic conductivity. Finally, we investigated the chemical properties, surface, inner layers atomic composition and C1s bonding state of biochar fragments through X-ray photoelectron spectroscopy (XPS). Ageing increased biochar skeletal density and reduced the water imbibition rate within fragments as a consequence of partial pore clogging. However, porosity and the volume of water stored in particles remained unchanged. Exposure reduced biochar pH, EC, and total C, but enhanced total N, nitrate-N, and ammonium-N. X-ray photoelectron spectroscopy analyses showed an increase of O, Si, N, Na, Al, Ca, Mn, and Fe surface (0–5 nm) atomic composition (at%) and a reduction of C and K in aged particles, confirming the interactions of biochar with soil inorganic and organic phases. Oxidation of aged biochar fragments occurred mainly in the particle surface, and progressively decreased down to 75 nm. Biochar surface chemistry changes included the development of carbonyl and carboxylate functional groups, again mainly on the particle surface. However, changes were noticeable down to 75 nm, while no significant changes were measured in the deepest layer, up to 110 nm. Results show unequivocal shifts in biochar physical and chemical properties/characteristics over short (~ years

  10. Biochar physico-chemical properties as affected by environmental exposure

    Energy Technology Data Exchange (ETDEWEB)

    Sorrenti, Giovambattista, E-mail: g.sorrenti@unibo.it [Department of Agricultural Sciences, University of Bologna, viale G. Fanin 44, 40127 Bologna (Italy); Masiello, Caroline A., E-mail: masiello@rice.edu [Departments of Earth Science, BioSciences, and Chemistry, Rice University, Houston, TX 77005 (United States); Dugan, Brandon, E-mail: dugan@rice.edu [Department of Earth Science, Rice University, Houston, TX 77005 (United States); Toselli, Moreno, E-mail: moreno.toselli@unibo.it [Department of Agricultural Sciences, University of Bologna, viale G. Fanin 44, 40127 Bologna (Italy)

    2016-09-01

    To best use biochar as a sustainable soil management and carbon (C) sequestration technique, we must understand the effect of environmental exposure on its physical and chemical properties because they likely vary with time. These properties play an important role in biochar's environmental behavior and delivery of ecosystem services. We measured biochar before amendment and four years after amendment to a commercial nectarine orchard at rates of 5, 15 and 30 t ha{sup −1}. We combined two pycnometry techniques to measure skeletal (ρ{sub s}) and envelope (ρ{sub e}) density and to estimate the total pore volume of biochar particles. We also examined imbibition, which can provide information about soil hydraulic conductivity. Finally, we investigated the chemical properties, surface, inner layers atomic composition and C1s bonding state of biochar fragments through X-ray photoelectron spectroscopy (XPS). Ageing increased biochar skeletal density and reduced the water imbibition rate within fragments as a consequence of partial pore clogging. However, porosity and the volume of water stored in particles remained unchanged. Exposure reduced biochar pH, EC, and total C, but enhanced total N, nitrate-N, and ammonium-N. X-ray photoelectron spectroscopy analyses showed an increase of O, Si, N, Na, Al, Ca, Mn, and Fe surface (0–5 nm) atomic composition (at%) and a reduction of C and K in aged particles, confirming the interactions of biochar with soil inorganic and organic phases. Oxidation of aged biochar fragments occurred mainly in the particle surface, and progressively decreased down to 75 nm. Biochar surface chemistry changes included the development of carbonyl and carboxylate functional groups, again mainly on the particle surface. However, changes were noticeable down to 75 nm, while no significant changes were measured in the deepest layer, up to 110 nm. Results show unequivocal shifts in biochar physical and chemical properties/characteristics over

  11. Modeling Engineered Nanomaterials (ENMs) Fate and Transport in Aquatic Ecosystems

    Science.gov (United States)

    Under the Toxic Substances Control Act (TSCA), the Environmental Protection Agency (EPA) is required to perform new chemical reviews of engineered nanomaterials (ENMs) identified in pre-manufacture notices. However, environmental fate models developed for traditional contaminants...

  12. Scandinavian belief in fate

    Directory of Open Access Journals (Sweden)

    Åke Ström

    1967-02-01

    Full Text Available In point of principle, Christianity does not give room for any belief in fate. Astrology, horoscopes, divination, etc., are strictly rejected. Belief in fate never disappeared in Christian countries, nor did it in Scandinavia in Christian times. Especially in folklore we can find it at any period: People believed in an implacable fate. All folklore is filled up with this belief in destiny. Nobody can escape his fate. The future lies in the hands of fate, and the time to come takes its form according to inscrutable laws. The pre-Christian period in Scandinavia, dominated by pagan Norse religion, and the secularized epoch of the 20th century, however, show more distinctive and more widespread beliefs in fate than does the Christian period. The present paper makes a comparison between these forms of belief.

  13. Environmental fate and ecotoxicological risk of the antibiotic sulfamethoxazole across the Katari catchment (Bolivian Altiplano) : application of the GREAT-ER model

    OpenAIRE

    Archundia, D.; Boithias, Laurie; Duwig, Céline; Morel, M. C.; Aviles, G. F.; Martins, J. M. F.

    2018-01-01

    Antibiotics are emergent contaminants that can induce adverse effects in terrestrial and aquatic organisms. The surface water compartment is of particular concern as it receives direct waste water discharge. Modeling is highlighted as an essential tool to understand the fate and behavior of these compounds and to assess their eco-toxicological risk. This study aims at testing the ability of the GREAT-ER model in simulating sulfamethoxazole (SMX) concentrations in the surface waters of the ari...

  14. Environmentally friendly properties of vegetable oil methyl esters

    Directory of Open Access Journals (Sweden)

    Gateau Paul

    2005-07-01

    Full Text Available Measurements were carried out on Vegetable Oil Methyl Esters (VOME or FAME answering the most recent specifications. The products tested are RME (Rapeseed oil Methyl Ester, ERME (Erucic Rapeseed oil Methyl Esters, SME (Sunflower oil Methyl Esters, and HOSME (High Oleic Sunflower oil Methyl Esters. They contain more than 99.5% of fatty acid mono esters. The compositions are given. VOME are not volatile and they are not easily flammable. They are not soluble in water and they are biodegradable. According to the methods implemented for the determination of the German classification of substances hazardous to waters WGK, they are not toxic on mammals and unlike diesel fuel they are not toxic on fish, daphnia, algae and bacteria. The RME is not either toxic for shrimps. According to tests on rabbits, RME and SME are not irritating for the skin and the eyes. VOME display particularly attractive environmental properties.

  15. Oil and gas property transfers: Analyzing the environmental risk through the environmental site assessment process

    International Nuclear Information System (INIS)

    Bratberg, D.; Hocker, S.

    1994-01-01

    The Superfund Act made anyone buying contaminated real estate liable for cleanup costs whether they know about the contamination or contributed to the contamination. In 1986, SARA amended the Superfund Act to include a provision known as the ''Innocent Landowner Defense.'' This provision created a defense for purchasers of contaminated property who did not contribute to the contamination and had no reason to believe that the property was contaminated at the time of the real estate transfer. SARA allows the purchasers and lenders to perform an environmental assessment using ''due diligence'' to identify contamination problems existing at a site. Since the passing of SARA, the environmental site assessment (ESA) process has become commonplace during the transfer of commercial real estate. Since the introduction of SARA, many professional associations, governmental agencies, and proposed federal legislation have struggled to produce a standard for conducting Phase 1 ESAs. Only recently has a standard been produced. Until recently, the domestic oil and gas industry has been relatively unconcerned about the Superfund liability issues. This approach was created by Congress's decision in 1980 to temporarily exempt the majority of oil and gas exploration and production wastes from federal hazardous waste rulings. However, new stringent rules governing oil and gas waste management practices are being considered by federal and state regulatory agencies. Based upon this knowledge and the awakening of public awareness, the use of ESAs for oil and gas transactions is increasing

  16. "Fate: The short film"

    OpenAIRE

    Maya Quintana, Jennifer

    2014-01-01

    "Fate: The Short Film" is a four minute short film which reflects the idea that nobody can escape from the fate. It has a good picture and sound quality with an understandable message for all public and with the collaboration of actors, filmmaker, stylist, script advisor and media technician.

  17. USEtox fate and ecotoxicity factors for comparative assessment of toxic emissions in Life Cycle Analysis

    DEFF Research Database (Denmark)

    Andrew D, Henderson; Hauschild, Michael Zwicky; Van de Meent, Dik

    2011-01-01

    orders of magnitude. However, for an emission to air or soil, differences in chemical properties may decrease the CF by up to 10 orders of magnitude, as a result of intermedia transfer and degradation. This result brings new clarity to the relative contributions of fate and freshwater ecotoxicity...... with characteristic properties, this work provides understanding of the basis for calculations of CFs in USEtox. In addition, it offers insight into the chemical properties and critical mechanisms covering the continuum from chemical emission to freshwater ecosystem toxicity. For an emission directly to water......The USEtox model was developed in a scientific consensus process involving comparison of and harmonization between existing environmental multimedia fate models. For freshwater ecosystem toxicity, it covers the entire impact pathway, i.e., transforming a chemical emission into potential impacts...

  18. Experimental methodology for assessing the environmental fate of organic chemicals in polymer matrices using column leaching studies and OECD 308 water/sediment systems: Application to tire and road wear particles

    International Nuclear Information System (INIS)

    Unice, Kenneth M.; Bare, Jennifer L.; Kreider, Marisa L.; Panko, Julie M.

    2015-01-01

    Automobile tires require functional rubber additives including curing agents and antioxidants, which are potentially environmentally available from tire and road wear particles (TRWP) deposited in soil and sediment. A novel methodology was employed to evaluate the environmental fate of three commonly-used tire chemicals (N-cyclohexylbenzothiazole-2-sulfenamide (CBS), N-(1,3-dimethylbutyl)-N′-phenyl-1,4-phenylenediamine (6-PPD) and 1,3-diphenylguanidine (DPG)), using a road simulator, an artificial weathering chamber, column leaching tests, and OECD 308 sediment/water incubator studies. Environmental release factors were quantified for curing (f C ), tire wear (f W ), terrestrial weathering (f S ), leaching from TRWP (f L ), and environmental availability from TRWP (f A ) by liquid chromatography–tandem mass spectroscopy (LC/MS/MS) analyses. Cumulative fractions representing total environmental availability (F T ) and release to water (F R ) were calculated for the tire chemicals and 13 transformation products. F T for CBS, DPG and 6-PPD inclusive of transformation products for an accelerated terrestrial aging time in soil of 0.1 years was 0.08, 0.1, and 0.06, respectively (equivalent to 6 to 10% of formulated mass). In contrast, a wider range of 5.5 × 10 −4 (6-PPD) to 0.06 (CBS) was observed for F R at an accelerated age of 0.1 years, reflecting the importance of hydrophobicity and solubility for determining the release to the water phase. Significant differences (p < 0.05) in the weathering factor, f S , were observed when chemicals were categorized by boiling point or hydrolysis rate constant. A significant difference in the leaching factor, f L , and environmental availability factor, f A, was also observed when chemicals were categorized by log K ow . Our methodology should be useful for lifecycle analysis of other functional polymer chemicals. - Highlights: • Studied two vulcanization accelerators and an antioxidant additive used in tire tread

  19. Experimental methodology for assessing the environmental fate of organic chemicals in polymer matrices using column leaching studies and OECD 308 water/sediment systems: Application to tire and road wear particles

    Energy Technology Data Exchange (ETDEWEB)

    Unice, Kenneth M., E-mail: ken.unice@cardno.com; Bare, Jennifer L.; Kreider, Marisa L.; Panko, Julie M.

    2015-11-15

    Automobile tires require functional rubber additives including curing agents and antioxidants, which are potentially environmentally available from tire and road wear particles (TRWP) deposited in soil and sediment. A novel methodology was employed to evaluate the environmental fate of three commonly-used tire chemicals (N-cyclohexylbenzothiazole-2-sulfenamide (CBS), N-(1,3-dimethylbutyl)-N′-phenyl-1,4-phenylenediamine (6-PPD) and 1,3-diphenylguanidine (DPG)), using a road simulator, an artificial weathering chamber, column leaching tests, and OECD 308 sediment/water incubator studies. Environmental release factors were quantified for curing (f{sub C}), tire wear (f{sub W}), terrestrial weathering (f{sub S}), leaching from TRWP (f{sub L}), and environmental availability from TRWP (f{sub A}) by liquid chromatography–tandem mass spectroscopy (LC/MS/MS) analyses. Cumulative fractions representing total environmental availability (F{sub T}) and release to water (F{sub R}) were calculated for the tire chemicals and 13 transformation products. F{sub T} for CBS, DPG and 6-PPD inclusive of transformation products for an accelerated terrestrial aging time in soil of 0.1 years was 0.08, 0.1, and 0.06, respectively (equivalent to 6 to 10% of formulated mass). In contrast, a wider range of 5.5 × 10{sup −4} (6-PPD) to 0.06 (CBS) was observed for F{sub R} at an accelerated age of 0.1 years, reflecting the importance of hydrophobicity and solubility for determining the release to the water phase. Significant differences (p < 0.05) in the weathering factor, f{sub S}, were observed when chemicals were categorized by boiling point or hydrolysis rate constant. A significant difference in the leaching factor, f{sub L}, and environmental availability factor, f{sub A,} was also observed when chemicals were categorized by log K{sub ow}. Our methodology should be useful for lifecycle analysis of other functional polymer chemicals. - Highlights: • Studied two vulcanization

  20. Development and Validation of Improved Techniques for Cloud Property Retrieval from Environmental Satellites

    National Research Council Canada - National Science Library

    Gustafson, Gary

    2000-01-01

    ...) develop extensible cloud property retrieval algorithms suitable for expanding existing cloud analysis capabilities to utilize data from new and future environmental satellite sensing systems; (2...

  1. Fate of pollutants

    International Nuclear Information System (INIS)

    Chapta, S.C.; Boyer, J.M.

    1990-01-01

    A literature review is presented of the fate of pollutants in sediment and water systems. Topics of discussion include the following: modeling, observations, and general studies; chlorinated xenobiotic chemicals; nonchlorinated xenobiotic chemicals; pesticides; heavy metals; and radionuclides

  2. Environmental fate of Ra in cation-exchange regeneration brine waste disposed to septic tanks, New Jersey Coastal Plain, USA: migration to the water table.

    Science.gov (United States)

    Szabo, Zoltan; Jacobsen, Eric; Kraemer, Thomas F; Parsa, Bahman

    2010-01-01

    Fate of radium (Ra) in liquid regeneration brine wastes from water softeners disposed to septic tanks in the New Jersey Coastal Plain was studied. Before treatment, combined Ra ((226)Ra plus (228)Ra) concentrations (maximum, 1.54 Bq L(-1)) exceeded the 0.185 Bq L(-1) Maximum Contaminant Level in 4 of 10 studied domestic-well waters (median pH, 4.90). At the water table downgradient from leachfields, combined Ra concentrations were low (commonly 5.3, indicating sequestration; when pH was septic-tank effluents (maximum, 0.243 Bq L(-1))), indicating Ra mobilization from leachfield sediments. Confidence in quantification of Ra mass balance was reduced by study design limitations, including synoptic sampling of effluents and ground waters, and large uncertainties associated with analytical methods. The trend of Ra mobilization in acidic environments does match observations from regional water-quality assessments.

  3. Experimental methodology for assessing the environmental fate of organic chemicals in polymer matrices using column leaching studies and OECD 308 water/sediment systems: Application to tire and road wear particles.

    Science.gov (United States)

    Unice, Kenneth M; Bare, Jennifer L; Kreider, Marisa L; Panko, Julie M

    2015-11-15

    Automobile tires require functional rubber additives including curing agents and antioxidants, which are potentially environmentally available from tire and road wear particles (TRWP) deposited in soil and sediment. A novel methodology was employed to evaluate the environmental fate of three commonly-used tire chemicals (N-cyclohexylbenzothiazole-2-sulfenamide (CBS), N-(1,3-dimethylbutyl)-N'-phenyl-1,4-phenylenediamine (6-PPD) and 1,3-diphenylguanidine (DPG)), using a road simulator, an artificial weathering chamber, column leaching tests, and OECD 308 sediment/water incubator studies. Environmental release factors were quantified for curing (f(C)), tire wear (f(W)), terrestrial weathering (f(S)), leaching from TRWP (f(L)), and environmental availability from TRWP (f(A)) by liquid chromatography-tandem mass spectroscopy (LC/MS/MS) analyses. Cumulative fractions representing total environmental availability (F(T)) and release to water (FR) were calculated for the tire chemicals and 13 transformation products. F(T) for CBS, DPG and 6-PPD inclusive of transformation products for an accelerated terrestrial aging time in soil of 0.1 years was 0.08, 0.1, and 0.06, respectively (equivalent to 6 to 10% of formulated mass). In contrast, a wider range of 5.5×10(-4) (6-PPD) to 0.06 (CBS) was observed for F(R) at an accelerated age of 0.1 years, reflecting the importance of hydrophobicity and solubility for determining the release to the water phase. Significant differences (p<0.05) in the weathering factor, f(S), were observed when chemicals were categorized by boiling point or hydrolysis rate constant. A significant difference in the leaching factor, f(L), and environmental availability factor, f(A), was also observed when chemicals were categorized by log K(ow). Our methodology should be useful for lifecycle analysis of other functional polymer chemicals. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. A multimedia fate model to evaluate the fate of PAHs in Songhua River, China

    International Nuclear Information System (INIS)

    Wang Ce; Feng Yujie; Sun Qingfang; Zhao Shanshan; Gao Peng; Li Bailian

    2012-01-01

    A multimedia fate model coupling dynamic water flow with a level IV fugacity model has been developed and applied to simulate the temporal and spatial fate of Polycyclic Aromatic Hydrocarbons (PAHs) in the Songhua River, China. The model has two components: in the first, the one-dimensional network kinematic wave equation is used to calculate varying water flow and depth. In the second, Fugacity IV equations are implemented to predict contaminant distributions in four environmental media. The estimated concentrations of eight PAHs in Songhua River are obtained, and all simulated results are in acceptable agreement with monitoring data, as verified with the Theil’s inequality coefficient test. The sensitivity of PAH concentration in each environmental phase to input parameters are also evaluated. Our results show the model predicts reasonably accurate contaminant concentrations in natural rivers, and that it can be used to supply necessary information for control and management of water pollution. - Highlights: ► The model used was developed based on kinematic wave equation and level IV fugacity principle. ► The model was applied to describe the fate and transport of organic chemicals in natural river. ► The concentrations of PAHs in water column were satisfactorily simulated when compared with monitoring data. ► Temporal and spatial variability of PAHs concentration among multimedia environmental phases was illustrated. - A dynamic water flow based multimedia fate model is developed to characterize the fate and transport of organic contaminant in natural rivers.

  5. Improving substance information in usetox®, part 2: Data for estimating fate and ecosystem exposure factors

    DEFF Research Database (Denmark)

    Saouter, Erwan; Aschberger, Karin; Fantke, Peter

    2017-01-01

    substance properties, USEtox® quantifies potential human toxicity and freshwater ecotoxicity impacts by combining environmental fate, exposure and toxicity effects information, considering multimedia fate and multi-pathway exposure processes. The main source to obtain substance properties for USEtox® 1......The scientific consensus model USEtox® is developed since 2003 under the auspices of the UNEP-SETAC Life Cycle Initiative as a harmonized approach for characterizing human and freshwater toxicity in life cycle assessment (LCA) and other comparative assessment frameworks. Using physicochemical.......01 and 2.0 is the Estimation Program Interface (EPI SuiteTM ) from the U.S. Environmental Protection Agency. However, since the development of the original USEtox® substance databases, new chemical regulations have been enforced in Europe such as the REACH and the Plant Protection Products regulations...

  6. Specialists meeting on properties of primary circuit structural materials including environmental effects

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1977-07-01

    The Specialists Meeting on Properties of Primary Circuit Structural Materials of LMFBRs covered the following topics: overview of materials program in different countries; mechanical properties of materials in air; fracture mechanics studies - component related activities; impact of environmental influences on mechanical properties; relationship of material properties and design methods. The purpose of the meeting was to provide a forum for exchange of information on structural materials behaviour in primary circuit of fast breeder reactors. Special emphasis was placed on environmental effects such as influence of sodium and irradiation on mechanical properties of reactor materials.

  7. Specialists meeting on properties of primary circuit structural materials including environmental effects

    International Nuclear Information System (INIS)

    1977-01-01

    The Specialists Meeting on Properties of Primary Circuit Structural Materials of LMFBRs covered the following topics: overview of materials program in different countries; mechanical properties of materials in air; fracture mechanics studies - component related activities; impact of environmental influences on mechanical properties; relationship of material properties and design methods. The purpose of the meeting was to provide a forum for exchange of information on structural materials behaviour in primary circuit of fast breeder reactors. Special emphasis was placed on environmental effects such as influence of sodium and irradiation on mechanical properties of reactor materials

  8. Title: Elucidation of Environmental Fate of Artificial Sweeteners (Aspartame, Acesulfame K and Saccharin) by Determining Bimolecular Rate Constants with Hydroxyl Radical at Various pH and Temperature Conditions and Possible Reaction By-Products

    Science.gov (United States)

    Teraji, T.; Arakaki, T.; Suzuka, T.

    2012-12-01

    Use of artificial sweeteners in beverages and food has been rapidly increasing because of their non-calorie nature. In Japan, aspartame, acesulfame K and sucralose are among the most widely used artificial sweeteners. Because the artificial sweeteners are not metabolized in human bodies, they are directly excreted into the environment without chemical transformations. We initiated a study to better understand the fate of artificial sweeteners in the marine environment. The hydroxyl radical (OH), the most potent reactive oxygen species, reacts with various compounds and determines the environmental oxidation capacity and the life-time of many compounds. The steady-state OH concentration and the reaction rate constants between the compound and OH are used to estimate the life-time of the compound. In this study, we determine the bimolecular rate constants between aspartame, acefulfame K and saccharin and OH at various pH and temperature conditions using a competition kinetics technique. We use hydrogen peroxide as a photochemical source of OH. Bimolecular rate constant we obtained so far for aspartame was (2.6±1.2)×109 M-1 s-1 at pH = 3.0 and (4.9±2.3)×109 M-1 s-1 at pH = 5.5. Little effect was seen by changing the temperatures between 15 and 40 oC. Activation energy (Ea) was calculated to be -1.0 kJ mol-1 at pH = 3.0, +8.5 kJ mol-1 at pH = 5.5, which could be regarded as zero. We will report bimolecular rate constants at different pHs and temperatures for acesulfame K and saccharin, as well. Possible reaction by-products for aspartame will be also reported. We will further discuss the fate of aspartame in the coastal environment.

  9. ENVIRONMENTAL RESEARCH BRIEF: THERMOPHYSICAL PROPERTIES OF HFE-125

    Science.gov (United States)

    Thermophysical properties of HFE-125 (pentafluorodimethylether) suggest that it could serve as an alternative non-ozone depleting refrigerant for certain low temperature applications. This Brief presents the thermophysical properties of HFE-125 (Tables 1-4) which have been obtai...

  10. Fate of As(V)-treated nano zero-valent iron: determination of arsenic desorption potential under varying environmental conditions by phosphate extraction.

    Science.gov (United States)

    Dong, Haoran; Guan, Xiaohong; Lo, Irene M C

    2012-09-01

    Nano zero-valent iron (NZVI) offers a promising approach for arsenic remediation, but the spent NZVI with elevated arsenic content could arouse safety concerns. This study investigated the fate of As(V)-treated NZVI (As-NZVI), by examining the desorption potential of As under varying conditions. The desorption kinetics of As from As-NZVI as induced by phosphate was well described by a biphasic rate model. The effects of As(V)/NZVI mass ratio, pH, and aging time on arsenic desorption from As-NZVI by phosphate were investigated. Less arsenic desorption was observed at lower pH or higher As(V)/NZVI mass ratio, where stronger complexes (bidentate) formed between As(V) and NZVI corrosion products as indicated by FTIR analysis. Compared with the fresh As-NZVI, the amount of phosphate-extractable As significantly decreased in As-NZVI aged for 30 or 60 days. The results of the sequential extraction experiments demonstrated that a larger fraction of As was sorbed in the crystalline phases after aging, making it less susceptible to phosphate displacement. However, at pH 9, a slightly higher proportion of phosphate-extractable As was observed in the 60-day sample than in the 30-day sample. XPS results revealed the transformation of As(V) to more easily desorbed As(III) during aging and a higher As(III)/As(V) ratio in the 60-day sample at pH 9, which might have resulted in the higher desorption. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Environmental Correlation and Spatial Autocorrelation of Soil Properties in Keller Peninsula, Maritime Antarctica

    Directory of Open Access Journals (Sweden)

    André Geraldo de Lima Moraes

    2018-01-01

    Full Text Available ABSTRACT: The pattern of variation in soil and landform properties in relation to environmental covariates are closely related to soil type distribution. The aim of this study was to apply digital soil mapping techniques to analysis of the pattern of soil property variation in relation to environmental covariates under periglacial conditions at Keller Peninsula, Maritime Antarctica. We considered the hypothesis that covariates normally used for environmental correlation elsewhere can be adequately employed in periglacial areas in Maritime Antarctica. For that purpose, 138 soil samples from 47 soil sites were collected for analysis of soil chemical and physical properties. We tested the correlation between soil properties (clay, potassium, sand, organic carbon, and pH and environmental covariates. The environmental covariates selected were correlated with soil properties according to the terrain attributes of the digital elevation model (DEM. The models evaluated were linear regression, ordinary kriging, and regression kriging. The best performance was obtained using normalized height as a covariate, with an R2 of 0.59 for sand. In contrast, the lowest R2 of 0.15 was obtained for organic carbon, also using the regression kriging method. Overall, results indicate that, despite the predominant periglacial conditions, the environmental covariates normally used for digital terrain mapping of soil properties worldwide can be successfully employed for understanding the main variations in soil properties and soil-forming factors in this region.

  12. Optimal environmental policy and the dynamic property in LDCs

    Directory of Open Access Journals (Sweden)

    Masahiro Yabuta

    2002-01-01

    Full Text Available This paper has provided a model framework of foreign assistance policy in the context of dynamic optimal control and investigated the environmental policies in LDCs that received some financial support from abroad. The model framework features a specific behavior of the social planner who determines the level of voluntary expenditure for preservation of natural environment. Because more financial needs for natural environmental protection means less allowance of growth-oriented investment, the social planner confronts a trade-off problem between economic growth and environmental preservation. To tackle with this clearly, we have built a dynamic model with two control variables: per-capita consumption and voluntary expenditure for natural environment.

  13. Environmentally friendly polymer nanocomposites: types, processing and properties

    CSIR Research Space (South Africa)

    Sinha Ray, S

    2013-07-01

    Full Text Available In recent years, the development of eco-friendly polymeric materials with balanced properties has become a subject of research attention due to concerns with increasing global-warming, carbon-emission, and limited natural resources. Nano...

  14. Recycled aggregates in concrete production: engineering properties and environmental impact

    OpenAIRE

    Seddik Meddah Mohammed

    2017-01-01

    Recycled concrete aggregate is considered as the most abundant and used secondary aggregate in concrete production, other types of solid waste are also being used in concrete for specific purposes and to achieve some desired properties. Recycled aggregates and particularly, recycled concrete aggregate substantially affect the properties and mix design of concrete both at fresh and hardened states since it is known by high porosity due to the adhered layer of old mortar on the aggregate which ...

  15. 41 CFR 102-80.10 - What are the basic safety and environmental management policies for real property?

    Science.gov (United States)

    2010-07-01

    ... safety and environmental management policies for real property? 102-80.10 Section 102-80.10 Public... MANAGEMENT REGULATION REAL PROPERTY 80-SAFETY AND ENVIRONMENTAL MANAGEMENT General Provisions § 102-80.10 What are the basic safety and environmental management policies for real property? The basic safety and...

  16. Potential environmental implications of nanoscale zero-valent iron particles for environmental remediation

    Directory of Open Access Journals (Sweden)

    Min-Hee Jang

    2014-12-01

    Full Text Available Objectives Nanoscale zero-valent iron (nZVI particles are widely used in the field of various environmental contaminant remediation. Although the potential benefits of nZVI are considerable, there is a distinct need to identify any potential risks after environmental exposure. In this respect, we review recent studies on the environmental applications and implications of nZVI, highlighting research gaps and suggesting future research directions. Methods Environmental application of nZVI is briefly summarized, focusing on its unique properties. Ecotoxicity of nZVI is reviewed according to type of organism, including bacteria, terrestrial organisms, and aquatic organisms. The environmental fate and transport of nZVI are also summarized with regards to exposure scenarios. Finally, the current limitations of risk determination are thoroughly provided. Results The ecotoxicity of nZVI depends on the composition, concentration, size and surface properties of the nanoparticles and the experimental method used, including the species investigated. In addition, the environmental fate and transport of nZVI appear to be complex and depend on the exposure duration and the exposure conditions. To date, field-scale data are limited and only short-term studies using simple exposure methods have been conducted. Conclusions In this regard, the primary focus of future study should be on 1 the development of an appropriate and valid testing method of the environmental fate and ecotoxicity of reactive nanoparticles used in environmental applications and 2 assessing their potential environmental risks using in situ field scale applications.

  17. Final Environmental Assessment Travis Air Force Base Burke Property Housing

    National Research Council Canada - National Science Library

    1999-01-01

    ... (40 CFR Parts 1500-1508) and Air Force Instruction 32-7061, the U.S. Air Force conducted an assessment of the potential environmental consequences of the construction of up to 281 military family housing units at Travis AFB...

  18. Effect of Environmental Quality on Property Rental Values in Peri ...

    African Journals Online (AJOL)

    The study examined the effect of environmental quality on rental values of residential accommodation at the peripheral neighbourhoods of Minna, Nigeria. Cluster sampling method was employed in the selection of sampled areas and, six neighbourhoods were randomly selected. Sample size of 600 was drawn out of the ...

  19. Simplified fate modelling in respect to ecotoxicological and human toxicological characterisation of emissions of chemical compounds

    DEFF Research Database (Denmark)

    Birkved, Morten; Heijungs, Reinout

    2011-01-01

    The impact assessment of chemical compounds in Life Cycle Impact Assessment (LCIA) and Environmental Risk Assessment (ERA) requires a vast amount of data on the properties of the chemical compounds being assessed. The purpose of the present study is to explore statistical options for reduction...... of the data demand associated with characterisation of chemical emissions in LCIA and ERA.Based on a USEtox™ characterisation factor set consisting of 3,073 data records, multi-dimensional bilinear models for emission compartment specific fate characterisation of chemical emissions were derived by application...... the independent chemical input parameters from the minimum data set, needed for characterisation in USEtox™, according to general availability, importance and relevance for fate factor prediction.Each approach (63% and 75% of the minimum data set needed for characterisation in USEtox™) yielded 66 meta...

  20. The effects of wildfire and environmental amenities on property values in northwest Montana, USA

    Science.gov (United States)

    Kyle M. Stetler; Tyron J. Venn; David E. Calkin

    2010-01-01

    This study employed the hedonic price framework to examine the effects of 256 wildfires and environmental amenities on home values in northwest Montana between June 1996 and January 2007. The study revealed environmental amenities, including proximity to lakes, national forests, Glacier National Park and golf courses, have large positive effects on property values in...

  1. Development and evaluation of the microbial fate and transport module for the Agricultural Policy/Environmental eXtender (APEX) model

    Science.gov (United States)

    Microbial contamination of waters in agricultural watershed is the critical public health issue. The watershed-scale model has been proven to be one of the candidate tools for predicting microbial water quality and evaluating management practices. The Agricultural Policy/Environmental eXtender (APEX...

  2. Ethical perspectives on the environmental impact of property ...

    African Journals Online (AJOL)

    Given the limitations of the instrumental and the intrinsic perspectives, it is suggested that the appropriate perspective to be adopted by ethical property developers is that of pragmatism, as being a system of moral pluralism. This perspective can be utilised as a flexible toolbox which unites both traditional ethical values and ...

  3. Chemical Transformation System: Cloud Based Cheminformatic Services to Support Integrated Environmental Modeling

    Science.gov (United States)

    Integrated Environmental Modeling (IEM) systems that account for the fate/transport of organics frequently require physicochemical properties as well as transformation products. A myriad of chemical property databases exist but these can be difficult to access and often do not co...

  4. Chemical Transformation System: Cloud Based Cheminformatic Services to Support Integrated Environmental Modeling (proceedings)

    Science.gov (United States)

    Integrated Environmental Modeling (IEM) systems that account for the fate/transport of organics frequently require physicochemical properties as well as transformation products. A myriad of chemical property databases exist but these can be difficult to access and often do not co...

  5. Applications of contaminant fate and bioaccumulation models in assessing ecological risks of chemicals: A case study for gasoline hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    MacLeod, Matthew; McKone, Thomas E.; Foster, Karen L.; Maddalena, Randy L.; Parkerton, Thomas F.; Mackay, Don

    2004-02-01

    Mass balance models of chemical fate and transport can be applied in ecological risk assessments for quantitative estimation of concentrations in air, water, soil and sediment. These concentrations can, in turn, be used to estimate organism exposures and ultimately internal tissue concentrations that can be compared to mode-of-action-based critical body residues that correspond to toxic effects. From this comparison, risks to the exposed organism can be evaluated. To illustrate the practical utility of fate models in ecological risk assessments of commercial products, the EQC model and a simple screening level biouptake model including three organisms, (a bird, a mammal and a fish) is applied to gasoline. In this analysis, gasoline is divided into 24 components or ''blocks'' with similar environmental fate properties that are assumed to elicit ecotoxicity via a narcotic mode of action. Results demonstrate that differences in chemical properties and mode of entry into the environment lead to profound differences in the efficiency of transport from emission to target biota. We discuss the implications of these results and insights gained into the regional fate and ecological risks associated with gasoline. This approach is particularly suitable for assessing mixtures of components that have similar modes of action. We conclude that the model-based methodologies presented are widely applicable for screening level ecological risk assessments that support effective chemicals management.

  6. The fate of pharmaceuticals and personal care products (PPCPs), endocrine disrupting contaminants (EDCs), metabolites and illicit drugs in a WWTW and environmental waters.

    Science.gov (United States)

    Archer, Edward; Petrie, Bruce; Kasprzyk-Hordern, Barbara; Wolfaardt, Gideon M

    2017-05-01

    A large number of emerging contaminants (ECs) are known to persist in surface waters, and create pressure on wastewater treatment works (WWTW) for their effective removal. Although a large database for the levels of these pollutants in water systems exist globally, there is still a lack in the correlation of the levels of these pollutants with possible long-term adverse health effects in wildlife and humans, such as endocrine disruption. The current study detected a total of 55 ECs in WWTW influent surface water, 41 ECs in effluent, and 40 ECs in environmental waters located upstream and downstream of the plant. A list of ECs persisted through the WWTW process, with 28% of all detected ECs removed by less than 50%, and 18% of all ECs were removed by less than 25%. Negative mass balances of some pharmaceuticals and metabolites were observed within the WWTW, suggesting possible back-transformation of ECs during wastewater treatment. Three parental illicit drug compounds were detected within the influent of the WWTW, with concentrations ranging between 27.6 and 147.0 ng L -1 for cocaine, 35.6-120.6 ng L -1 for mephedrone, and 270.9-450.2 ng L -1 for methamphetamine. The related environmental risks are also discussed for some ECs, with particular reference to their ability to disrupt endocrine systems. The current study propose the potential of the pharmaceuticals carbamazepine, naproxen, diclofenac and ibuprofen to be regarded as priority ECs for environmental monitoring due to their regular detection and persistence in environmental waters and their possible contribution towards adverse health effects in humans and wildlife. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Cell fate determination dynamics in bacteria

    Science.gov (United States)

    Kuchina, Anna; Espinar, Lorena; Cagatay, Tolga; Garcia-Ojalvo, Jordi; Suel, Gurol

    2010-03-01

    The fitness of an organism depends on many processes that serve the purpose to adapt to changing environment in a robust and coordinated fashion. One example of such process is cellular fate determination. In the presence of a variety of alternative responses each cell adopting a particular fate represents a ``choice'' that must be tightly regulated to ensure the best survival strategy for the population taking into account the broad range of possible environmental challenges. We investigated this problem in the model organism B.Subtilis which under stress conditions differentiates terminally into highly resistant spores or initiates an alternative transient state of competence. The dynamics underlying cell fate choice remains largely unknown. We utilize quantitative fluorescent microscopy to track the activities of genes involved in these responses on a single-cell level. We explored the importance of temporal interactions between competing cell fates by re- engineering the differentiation programs. I will discuss how the precise dynamics of cellular ``decision-making'' governed by the corresponding biological circuits may enable cells to adjust to diverse environments and determine survival.

  8. Characteristics and environmental fate of the anionic surfactant sodium lauryl ether sulphate (SLES) used as the main component in foaming agents for mechanized tunnelling

    International Nuclear Information System (INIS)

    Barra Caracciolo, Anna; Cardoni, Martina; Pescatore, Tanita; Patrolecco, Luisa

    2017-01-01

    The anionic surfactant sodium lauryl ether sulphate (SLES) is the main component of most commercial products used for soil conditioning in the excavation industry, in particular as lubricants for mechanized tunnelling. Its use during the excavation processes can result in either the subsequent possible re-use of the huge amount of soil debris as by-products (e.g. land covering) or its discharge as waste. Currently, there are neither SLES soil threshold limits in European legislation, nor comprehensive studies on the environmental risk for soil ecosystems in these exposure scenarios. In this context, the present paper reviews the available data on the intrinsic characteristics of persistence and the ecotoxicological effects of the anionic surfactant SLES. Although SLES is generally reported to be biodegradable in standard tests, with degradation rates between 7 h and 30 days, depending on the initial conditions, data on its biodegradation in environmental studies are quite scarce. Consequently, assessing SLES biodegradation rates in field conditions is crucial for evaluating if in residual concentrations (typically in the range 40–500 mg/kg in excavated soils) it can or not be a potential hazard for terrestrial and water organisms. Laboratory ecotoxicological tests pointed out detrimental effects of SLES for aquatic organisms, while data on the terrestrial species are rather poor so far and further studies at the expected environmental concentrations are necessary. Finally, the review reports the main analytical methods available for detecting anionic surfactants in solid matrices and the future research needed to improve knowledge on the possible environmental risks posed by the use of SLES in foaming agents for mechanized tunnelling. - Highlights: • Tons of excavated soil containing SLES are reused posing an environmental risk. • SLES can have detrimental effects on aquatic organisms exposed in lab test. • There is a need to improve knowledge on SLES

  9. Null Environmental Effects of the Cosmic Web on Dark Matter Halo Properties

    Science.gov (United States)

    Goh, Tze; Primack, Joel; Aragon-Calvo, Miguel; Hellinger, Doug; Rodriguez-Puebla, Aldo; Lee, Christoph; Eckleholm, Elliot; Johnston, Kathryn

    2018-01-01

    We study the effects of the cosmic web environment (filaments, voids and walls) and environmental density on key properties of dark matter halos at redshift z = 0 using the Bolshoi-Planck ΛCDM. The z=0 Bolshoi-Planck simulation is analysed into filaments, voids and walls using the SpineWeb method, as well as VIDE method, both of which use Voronoi tessellation and the watershed transform. The key halo properties that we study are the mass accretion rate, spin parameter, concentration, prolateness, scale factor of the last major merger, and scale factor when the halo had half of its z=0 mass. For all these properties, we find that there is no discernible difference between the halo properties in filaments, walls or voids when compared at the same environmental density. As a result, we conclude that environmental density is the core attribute that affects these properties. This conclusion is in line with recent findings that properties of galaxies in redshift surveys are independent of their cosmic web environment at the same environmental density. We also find that the local web environment of the Milky Way and the Andromeda galaxy near the centre of a cosmic wall does not appear to have any effect on the key properties of these galaxies' dark matter halos, although we find that it is rather rare to have such massive halos near the centre of a relatively small cosmic wall.

  10. Radionuclide fate and effects

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    The studies reported here deal with the full range of contaminant behavior and fate, from the initial physicochemical factors that govern radionuclide availability in terrestrial and aquatic environments to studies of contaminant transport by biological means. By design, we focus more on the biologically and chemically mediated transport processes and food-chain pathways than on the purely physical forms of contaminant transport, such as transport by wind and water

  11. Tuning CNT Properties for Metal-Free Environmental Catalytic Applications

    Directory of Open Access Journals (Sweden)

    Raquel P. Rocha

    2016-06-01

    Full Text Available The application of carbon nanotubes (CNTs as metal-free catalysts is a novel approach for heterogeneous liquid phase catalytic systems. Textural and chemical modifications by liquid/gas phase or mechanical treatments, as well as solid state reactions, were successfully applied to obtain carbon nanotubes with different surface functionalities. Oxygen, nitrogen, and sulfur are the most common heteroatoms introduced on the carbon surface. This short-review highlights different routes used to develop metal-free carbon nanotube catalysts with enhanced properties for Advanced Oxidation Processes.

  12. Assessing the transport and fate of bioengineered microorganisms in the environment

    International Nuclear Information System (INIS)

    Barnthouse, L.W.; Palumbo, A.V.

    1985-01-01

    We review the methods currently available for quantifying the transport and fate of microbes in atmospheric and aqueous media and assess their adequacy for purposes of risk assessment. We review the literature on transport and fate of microorganisms, including studies of: (1) pathways of migration, (2) the survival of microorganisms during transport and fate. In addition, we review the transport and fate models that have been used in environmental risk assessments for radionuclides and toxic chemicals and evaluate their applicability to the problem of assessing environmental risks of bioengineered microorganisms

  13. Production of environmentally friendly aerated concrete with required construction and operational properties

    Directory of Open Access Journals (Sweden)

    Tkach Evgeniya

    2018-01-01

    Full Text Available The purpose of these studies is to justify the feasibility of recycling different types of industrial waste instead of conventional expensive raw materials in production of environmentally friendly aerated concrete with required construction and operational properties. The impact of wastes from various industries on the environmental condition of affected areas, as well as the results of their environmental assessment were analyzed to determine whether these wastes could be used in production of high-performance building materials. The assessment of industrial wastes in aerated concrete production suggests that industrial wastes of hazard class IV can be recycled to produce aerated concrete. An environmentally friendly method for large-scale waste recycling, including a two-step environmentally sustainable mechanism, was developed. The basic quality indicators of the modified aerated concrete proved that the environmental safety could be enhanced by strengthening the structure, increasing its uniformity and improving thermal insulation properties. The modified non-autoclaved aerated concrete products with improved physical and operational properties were developed. They have the following properties: density – D700; class of concrete – B3.5; thermal transmittance coefficient – 0.143 W/(m·°C; frost resistance – F75.

  14. Plant trait-species abundance relationships vary with environmental properties in subtropical forests in eastern china.

    Directory of Open Access Journals (Sweden)

    En-Rong Yan

    Full Text Available Understanding how plant trait-species abundance relationships change with a range of single and multivariate environmental properties is crucial for explaining species abundance and rarity. In this study, the abundance of 94 woody plant species was examined and related to 15 plant leaf and wood traits at both local and landscape scales involving 31 plots in subtropical forests in eastern China. Further, plant trait-species abundance relationships were related to a range of single and multivariate (PCA axes environmental properties such as air humidity, soil moisture content, soil temperature, soil pH, and soil organic matter, nitrogen (N and phosphorus (P contents. At the landscape scale, plant maximum height, and twig and stem wood densities were positively correlated, whereas mean leaf area (MLA, leaf N concentration (LN, and total leaf area per twig size (TLA were negatively correlated with species abundance. At the plot scale, plant maximum height, leaf and twig dry matter contents, twig and stem wood densities were positively correlated, but MLA, specific leaf area, LN, leaf P concentration and TLA were negatively correlated with species abundance. Plant trait-species abundance relationships shifted over the range of seven single environmental properties and along multivariate environmental axes in a similar way. In conclusion, strong relationships between plant traits and species abundance existed among and within communities. Significant shifts in plant trait-species abundance relationships in a range of environmental properties suggest strong environmental filtering processes that influence species abundance and rarity in the studied subtropical forests.

  15. Environmental effects on the compressive properties - Thermosetting vs. thermoplastic composites

    Science.gov (United States)

    Haque, A.; Jeelani, S.

    1992-01-01

    The influence of moisture and temperature on the compressive properties of graphite/epoxy and APC-2 materials systems was investigated to assess the viability of using APC-2 instead of graphite/epoxy. Data obtained indicate that the moisture absorption rate of T-300/epoxy is higher than that of APC-2. Thick plate with smaller surface area absorbs less moisture than thin plate with larger surface area. The compressive strength and modulus of APC-2 are higher than those of T-300/epoxy composite, and APC-2 sustains higher compressive strength in the presence of moisture. The compressive strength and modulus decrease with the increase of temperature in the range of 23-100 C. The compression failure was in the form of delamination, interlaminar shear, and end brooming.

  16. Characterization of the Flow Field and Wind Speed Profiles in Microbalance Wind Tunnels for Measurement of Agent Fate

    National Research Council Canada - National Science Library

    Weber, Daniel J; Molnar, John W; Scudder, Mary K; Shuely, Wendel

    2005-01-01

    An important goal is to model chemical warfare agent fate on environmental and interior surfaces and therefore, rigorously measured evaporation and desorption rates are required to develop equations...

  17. A review of environmental fate, body burdens, and human health risk assessment of PCDD/Fs at two typical electronic waste recycling sites in China

    International Nuclear Information System (INIS)

    Chan, Janet Kit Yan; Wong, Ming H.

    2013-01-01

    This paper reviews the levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in different environmental media, human body burdens and health risk assessment results at e-waste recycling sites in China. To provide an indication of the seriousness of the pollution levels in the e-waste recycling sites in China, the data are compared with guidelines and available existing data for other areas. The comparison clearly shows that PCDD/Fs derived from the recycling processes lead to serious pollution in different environmental compartments (such as air, soil, sediment, dust and biota) and heavy body burdens. Of all kinds of e-waste recycling operations, open burning of e-waste and acid leaching activities are identified as the major sources of PCDD/Fs. Deriving from the published data, the estimated total exposure doses via dietary intake, inhalation, soil/dust ingestion and dermal contact are calculated for adults, children and breast-fed infants living in two major e-waste processing locations in China. The values ranged from 5.59 to 105.16 pg WHO-TEQ/kg bw/day, exceeding the tolerable daily intakes recommended by the WHO (1–4 pg WHO-TEQ/kg bw/day). Dietary intake is the most important exposure route for infants, children and adults living in these sites, contributing 60–99% of the total intakes. Inhalation is the second major exposure route, accounted for 12–30% of the total exposure doses of children and adults. In order to protect the environment and human health, there is an urgent need to control and monitor the informal e-waste recycling operations. Knowledge gaps, such as comprehensive dietary exposure data, epidemiological and clinical studies, body burdens of infants and children, and kinetics about PCDD/Fs partitions among different human tissues should be addressed. - Highlights: ► PCDD/F levels at e-waste recycling sites in China were reviewed. ► Data on environment and body burden and health risk assessment results were reviewed

  18. A review of environmental fate, body burdens, and human health risk assessment of PCDD/Fs at two typical electronic waste recycling sites in China

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Janet Kit Yan, E-mail: chanjky@hku.hk [School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong (China); Wong, Ming H., E-mail: mhwong@hkbu.edu.hk [Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University, Hong Kong (China)

    2013-10-01

    This paper reviews the levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in different environmental media, human body burdens and health risk assessment results at e-waste recycling sites in China. To provide an indication of the seriousness of the pollution levels in the e-waste recycling sites in China, the data are compared with guidelines and available existing data for other areas. The comparison clearly shows that PCDD/Fs derived from the recycling processes lead to serious pollution in different environmental compartments (such as air, soil, sediment, dust and biota) and heavy body burdens. Of all kinds of e-waste recycling operations, open burning of e-waste and acid leaching activities are identified as the major sources of PCDD/Fs. Deriving from the published data, the estimated total exposure doses via dietary intake, inhalation, soil/dust ingestion and dermal contact are calculated for adults, children and breast-fed infants living in two major e-waste processing locations in China. The values ranged from 5.59 to 105.16 pg WHO-TEQ/kg bw/day, exceeding the tolerable daily intakes recommended by the WHO (1–4 pg WHO-TEQ/kg bw/day). Dietary intake is the most important exposure route for infants, children and adults living in these sites, contributing 60–99% of the total intakes. Inhalation is the second major exposure route, accounted for 12–30% of the total exposure doses of children and adults. In order to protect the environment and human health, there is an urgent need to control and monitor the informal e-waste recycling operations. Knowledge gaps, such as comprehensive dietary exposure data, epidemiological and clinical studies, body burdens of infants and children, and kinetics about PCDD/Fs partitions among different human tissues should be addressed. - Highlights: ► PCDD/F levels at e-waste recycling sites in China were reviewed. ► Data on environment and body burden and health risk assessment results were reviewed

  19. Modelling the fate of organic micropollutants in stormwater ponds

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Eriksson, Eva; Ledin, Anna

    2011-01-01

    ). The four simulated organic stormwater MP (iodopropynyl butylcarbamate — IPBC, benzene, glyphosate and pyrene) were selected according to their different urban sources and environmental fate. This ensures that the results can be extended to other relevant stormwater pollutants. All three models use......Urban water managers need to estimate the potential removal of organic micropollutants (MP) in stormwater treatment systems to support MP pollution control strategies. This study documents how the potential removal of organic MP in stormwater treatment systems can be quantified by using multimedia...... models. The fate of four different MP in a stormwater retention pond was simulated by applying two steady-state multimedia fate models (EPI Suite and SimpleBox) commonly applied in chemical risk assessment and a dynamic multimedia fate model (Stormwater Treatment Unit Model for Micro Pollutants — STUMP...

  20. Environmental and management influences on temporal variability of near saturated soil hydraulic properties.

    Science.gov (United States)

    Bodner, G; Scholl, P; Loiskandl, W; Kaul, H-P

    2013-08-01

    Structural porosity is a decisive property for soil productivity and soil environmental functions. Hydraulic properties in the structural range vary over time in response to management and environmental influences. Although this is widely recognized, there are few field studies that determine dominant driving forces underlying hydraulic property dynamics. During a three year field experiment we measured temporal variability of soil hydraulic properties by tension infiltrometry. Soil properties were characterized by hydraulic conductivity, effective macroporosity and Kosugi's lognormal pore size distribution model. Management related influences comprised three soil cover treatment (mustard and rye vs. fallow) and an initial mechanical soil disturbance with a rotary harrow. Environmental driving forces were derived from meteorological and soil moisture data. Soil hydraulic parameters varied over time by around one order of magnitude. The coefficient of variation of soil hydraulic conductivity K(h) decreased from 69.5% at saturation to 42.1% in the more unsaturated range (- 10 cm pressure head). A slight increase in the Kosugi parameter showing pore heterogeneity was observed under the rye cover crop, reflecting an enhanced structural porosity. The other hydraulic parameters were not significantly influenced by the soil cover treatments. Seedbed preparation with a rotary harrow resulted in a fourfold increase in macroporosity and hydraulic conductivity next to saturation, and homogenized the pore radius distribution. Re-consolidation after mechanical loosening lasted over 18 months until the soil returned to its initial state. The post-tillage trend of soil settlement could be approximated by an exponential decay function. Among environmental factors, wetting-drying cycles were identified as dominant driving force explaining short term hydraulic property changes within the season (r 2  = 0.43 to 0.59). Our results suggested that beside considering average

  1. A conceptual study on the formulation of a permeable reactive pavement with activated carbon additives for controlling the fate of non-point source environmental organic contaminants.

    Science.gov (United States)

    Huang, Shengyi; Liang, Chenju

    2018-02-01

    To take advantage of the road pavement network where non-point source (NPS) pollution such as benzene, toluene, ethyl-benzene, and xylene (BTEX) from vehicle traffic exhaust via wet and dry atmospheric deposition occurs, the asphalt pavement may be used as a media to control the NPS pollution. An experiment to prepare an adsorptive porous reactive pavement (PRP) was initiated to explore the potential to reduce environmental NPS vehicle pollution. The PRP was prepared and studied as follows: various activated carbons (AC) were initially screened to determine if they were suitable as an additive in the porous asphalt mixture; various mixtures of a selected AC were incorporated with the design of porous asphalt concrete (PAC) to produce PRP, and the PRP formulations were tested to ensure that they comply with the required specifications; qualified specimens were subsequently tested to determine their adsorption capacity for BTEX in aqueous solution, as compared to conventional PAC. The PRP08 and PRP16 samples, named for the design formulations of 0.8% and 1.6% of AC (by wt. in the formulation), exhibited low asphalt drain-down and low abrasion loss and also met all regulated specifications. The BTEX adsorption capacity measurements of PRP08 and PRP16 were 33-46%, 36-51%, 20-22%, and 6-8% respectively, higher than those obtained from PACs. Based on the test results, PRPs showed good physical performance and adsorption and may be considered as a potential method for controlling the transport of NPS vehicle pollutants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Group contribution modelling for the prediction of safety-related and environmental properties

    DEFF Research Database (Denmark)

    Frutiger, Jerome; Abildskov, Jens; Sin, Gürkan

    warming potential and ozone depletion potential. Process safety studies and environmental assessments rely on accurate property data. Safety data such as flammability limits, heat of combustion or auto ignition temperature play an important role in quantifying the risk of fire and explosions among others......We present a new set of property prediction models based on group contributions to predict major safety-related and environmental properties for organic compounds. The predicted list of properties includes lower and upper flammability limits, heat of combustion, auto ignition temperature, global...... models like group contribution (GC) models can estimate data. However, the estimation needs to be accurate, reliable and as little time-consuming as possible so that the models can be used on the fly. In this study the Marrero and Gani group contribution (MR GC) method has been used to develop the models...

  3. The dispense of legal reserve in the registration of property: decrease of environmental protection?

    Directory of Open Access Journals (Sweden)

    Thiago de Miranda Carneiro

    2016-12-01

    Full Text Available It is intended to analyze the rural environmental registry and exemption from the registration of the legal reserve on the basis of Law 12.651/12. They will be addressed elements of environmental protection and real estate to handle the revocation of registration of the legal reserve in real estate registry and their inclusion in the CAR, as well as property registration paper and registral advertising in order to ascertain the legal traffic safety real estate. We used exploratory method  through literature and document analysis starting at the constitutional and environmental law through the registral law.

  4. Environmental Risk Assessment of antimicrobials applied in veterinary medicine-A field study and laboratory approach.

    Science.gov (United States)

    Slana, Marko; Dolenc, Marija Sollner

    2013-01-01

    The fate and environmental risk of antimicrobial compounds of different groups of veterinary medicine pharmaceuticals (VMP's) have been compared. The aim was to demonstrate a correlation between the physical and chemical properties of active compounds and their metabolism in target animals, as well as their fate in the environment. In addition, the importance of techniques for manure management and agricultural practice and their influence on the fate of active compounds is discussed. The selected active compounds are shown to be susceptible to at least one environmental factor (sun, water, bacterial or fungal degradation) to which they are exposed during their life cycle, which contributes to its degradation. Degradation under a number of environmental factors has also to be considered as authentic information additional to that observed in the limited conditions in laboratory studies and in Environmental Risk Assessment calculations. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Choice of pesticide fate models

    International Nuclear Information System (INIS)

    Balderacchi, Matteo; Trevisan, Marco; Vischetti, Costantino

    2006-01-01

    The choice of a pesticide fate model at field scale is linked to the available input data. The article describes the available pesticide fate models at a field scale and the guidelines for the choice of the suitable model as function of the data input requested [it

  6. Modeling Engineered Nanomaterials (ENMs) Fate and ...

    Science.gov (United States)

    Under the Toxic Substances Control Act (TSCA), the Environmental Protection Agency (EPA) is required to perform new chemical reviews of engineered nanomaterials (ENMs) identified in pre-manufacture notices. However, environmental fate models developed for traditional contaminants are limited in their ability to simulate the environmental behavior of nanomaterials due to incomplete understanding and representation of the processes governing nanomaterial distribution in the environment and by scarce empirical data quantifying the interaction of nanomaterials with environmental surfaces. We have updated the Water Quality Analysis Simulation Program (WASP), version S, to incorporate nanomaterials as an explicitly simulated state variable. WASPS now has the capability to simulate nanomaterial fate and transport in surface waters and sediments using heteroaggregation, the kinetic process governing the attachment of nanomaterials to particles and subsequently ENM distribution in the aqueous and sediment phases. Unlike dissolved chemicals which use equilibrium partition coefficients, heteroaggregation consists of a particle collision rate and an attachment efficiency ( lXhet) that generally acts as a one direction process. To demonstrate, we used a derived a het value from sediment attachment studies to parameterize WASP for simulation of multi walled carbon nanotube (MWCNT) transport in Brier Creek, a coastal plain river located in central eastern Georgia, USA and a tr

  7. Fate factors and emission flux estimates for emerging contaminants in surface waters

    Directory of Open Access Journals (Sweden)

    Hoa T. Trinh

    2016-01-01

    Full Text Available Pharmaceuticals, personal care products, hormones, and wastewater products are emerging environmental concerns for manifold reasons, including the potential of some compounds found in these products for endocrine disruption at a very low chronic exposure level. The environmental occurrences and sources of these contaminants in the water, soil, sediment and biota in European nations and the United States are well documented. This work reports a screening-level emission and fate assessment of thirty compounds, listed in the National Reconnaissance of the United States Geological Survey (USGS, 1999–2000 as the most frequently detected organic wastewater contaminants in U.S. streams and rivers. Estimations of the surface water fate factors were based on Level II and Level III multimedia fugacity models for a 1000 km2 model environment, the size of a typical county in the eastern United States. The compounds are categorized into three groups based upon the sensitivity of their predicted surface water fate factors to uncertainties in their physicochemical property values and the landscape parameters. The environmental fate factors, mass distributions, and loss pathways of all of the compounds are strongly affected by their assumed modes of entry into the environment. It is observed that for thirteen of the thirty organic wastewater contaminants most commonly detected in surface waters, conventional treatment strategies may be ineffective for their removal from wastewater effluents. The surface water fate factors predicted by the fugacity models were used in conjunction with the surface water concentrations measured in the USGS reconnaissance to obtain emission flux estimates for the compounds into U.S. streams and rivers. These include estimated fluxes of 6.8 × 10−5 to 0.30 kg/h km2 for the biomarker coprostanol; 1.7 × 10−5 to 6.5 × 10−5 kg/h km2 for the insect repellent N,N-diethyltoluamide; and 4.3 × 10−6 to 3.1 × 10−5 kg/h km2 for

  8. EVALUATION OF THE STATE-OF-THE-ART CONTAMINATED SEDIMENT TRANSPORT AND FATE MODELING SYSTEM

    Science.gov (United States)

    Modeling approaches for evaluating the transport and fate of sediment and associated contaminants are briefly reviewed. The main emphasis is on: 1) the application of EFDC (Environmental Fluid Dynamics Code), the state-of-the-art contaminated sediment transport and fate public do...

  9. Pollutant transport and fate in ecosystems

    International Nuclear Information System (INIS)

    Coughtrey, P.J.; Martin, M.H.; Unsworth, M.H.

    1987-01-01

    This publication contains a selection of the papers that were presented at a meeting of the Industrial Ecology Group of the British Ecological Society, held at the University of Bristol 1-4 April 1985. The aim of the meeting was to discuss the processes and mechanisms underlying the transfer of pollutants and contaminants in ecological systems. The discussion of the impact of pollutants on individual organisms, populations and communities was specifically excluded. Parallels between transfer, distribution and fate of a wide range of materials were identified. The papers presented at the meeting provided examples of mechanisms and processes involved in pollutant transport through ecosystems as well as of the significance of long-term or widespread investigations in the identification of temporal or geographical trends. Examples were also provided of studies involving complex systems and diverse materials with the aim of identifying underlying principles. Topics of current environmental concern e.g. acid deposition, heavy metals, radioactivity, etc. for which information is being collated in order to provide a basis for assessments concerning future impact were presented. Such assessments will require a combination of the information on transport and fate within ecosystems with knowledge of the effects of pollutants on the system. The interpretation of data concerning effects of a pollutant needs to be placed in the wider context of the occurrence, distribution and fate of that pollutant. The purpose of this publication is to provide that wider context. (author)

  10. Prediction of soil properties for agricultural and environmental applications from infrared and X-ray soil spectral properties

    International Nuclear Information System (INIS)

    Towett, Erick Kibet

    2013-01-01

    Many of today's most pressing problems facing developing countries, such as food security, climate change, and environmental protection, require large area data on soil functional capacity. Conventional assessments (methods and measurements) of soil capacity to perform specific agricultural and environmental functions are time consuming and expensive. In addition, repeatability, reproducibility and accuracy of conventional soil analytical data are major challenges. New, rapid methods to quantify soil properties are needed, especially in developing countries where reliable data on soil properties is sparse, and to take advantage of new opportunities for digital soil mapping. Mid infrared diffuse reflectance spectroscopy (MIR) has already shown promise as a rapid analytical tool and there are new opportunities to include other high-throughput techniques, such as total X-ray fluorescence (TXRF), and X-ray diffraction (XRD) spectroscopy. In this study TXRF and XRD were tested in conjunction with IR to provide powerful diagnostic capabilities for the direct prediction of key soil properties for agricultural and environmental applications especially for Sub-Saharan Africa (SSA) soils. Optimal combinations of spectral methods for use in pedotransfer functions for low cost, rapid prediction of chemical and physical properties of African soils as well as prediction models for soil organic carbon and soil fertility properties (soil extractable nutrients, pH and exchangeable acidity) were tested in this study. This study has developed and tested a method for the use of TXRF for direct quantification of total element concentrations in soils using a TXRF (S2 PICOFOX trademark) spectrometer and demonstrated that TXRF could be used as a rapid screening tool for total element concentrations in soils assuming sufficient calibration measures are followed. The results of the current study have shown that TXRF can provide efficient chemical fingerprinting which could be further

  11. Prediction of soil properties for agricultural and environmental applications from infrared and X-ray soil spectral properties

    Energy Technology Data Exchange (ETDEWEB)

    Towett, Erick Kibet

    2013-12-09

    Many of today's most pressing problems facing developing countries, such as food security, climate change, and environmental protection, require large area data on soil functional capacity. Conventional assessments (methods and measurements) of soil capacity to perform specific agricultural and environmental functions are time consuming and expensive. In addition, repeatability, reproducibility and accuracy of conventional soil analytical data are major challenges. New, rapid methods to quantify soil properties are needed, especially in developing countries where reliable data on soil properties is sparse, and to take advantage of new opportunities for digital soil mapping. Mid infrared diffuse reflectance spectroscopy (MIR) has already shown promise as a rapid analytical tool and there are new opportunities to include other high-throughput techniques, such as total X-ray fluorescence (TXRF), and X-ray diffraction (XRD) spectroscopy. In this study TXRF and XRD were tested in conjunction with IR to provide powerful diagnostic capabilities for the direct prediction of key soil properties for agricultural and environmental applications especially for Sub-Saharan Africa (SSA) soils. Optimal combinations of spectral methods for use in pedotransfer functions for low cost, rapid prediction of chemical and physical properties of African soils as well as prediction models for soil organic carbon and soil fertility properties (soil extractable nutrients, pH and exchangeable acidity) were tested in this study. This study has developed and tested a method for the use of TXRF for direct quantification of total element concentrations in soils using a TXRF (S2 PICOFOX trademark) spectrometer and demonstrated that TXRF could be used as a rapid screening tool for total element concentrations in soils assuming sufficient calibration measures are followed. The results of the current study have shown that TXRF can provide efficient chemical fingerprinting which could be further

  12. Mechanical Properties of Air Plasma Sprayed Environmental Barrier Coating (EBC) Materials

    Science.gov (United States)

    Richards, Bradley; Zhu, Dongming; Ghosn, Louis; Wadley, Haydn

    2015-01-01

    Development work in Environmental Barrier Coatings (EBCs) for Ceramic Matrix Composites (CMCs) has focused considerably on the identification of materials systems and coating architectures to meet application needs. The evolution of these systems has occurred so quickly that modeling efforts and requisite data for modeling lag considerably behind development. Materials property data exists for many systems in the bulk form, but the effects of deposition on the critical properties of strength and fracture behavior are not well studied. We have plasma sprayed bulk samples of baseline EBC materials (silicon, ytterbium disilicate) and tested the mechanical properties of these materials to elicit differences in strength and toughness. We have also endeavored to assess the mixed-mode fracture resistance, Gc, of silicon in a baseline EBC applied to SiCSiC CMC via four point bend test. These results are compared to previously determined properties of the comparable bulk material.

  13. Models of Fate and Transport of Pollutants in Surface Waters

    Science.gov (United States)

    Okome, Gloria Eloho

    2013-01-01

    There is the need to answer very crucial questions of "what happens to pollutants in surface waters?" This question must be answered to determine the factors controlling fate and transport of chemicals and their evolutionary state in surface waters. Monitoring and experimental methods are used in establishing the environmental states.…

  14. Programmatic Environmental Report for remedial actions at UMTRA [Uranium Mill Tailings Remedial Action] Project vicinity properties

    International Nuclear Information System (INIS)

    1985-03-01

    This Environmental Report (ER) examines the environmental consequences of implementing a remedial action that would remove radioactive uranium mill tailings and associated contaminated materials from 394 vicinity properties near 14 inactive uranium processing sites included in the Uranium Mill Tailings Remedial Action (UMTRA) Project pursuant to Public Law 95--604, the Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978. Vicinity properties are those properties in the vicinity of the UMTRA Project inactive mill sites, either public or private, that are believed to be contaminated by residual radioactive material originating from one of the 14 inactive uranium processing sites, and which have been designated under Section 102(a)(1) of UMTRCA. The principal hazard associated with the contaminated properties results from the production of radon, a radioactive decay product of the radium contained in the tailings. Radon, a radioactive gas, can diffuse through the contaminated material and be released into the atmosphere where it and its radioactive decay products may be inhaled by humans. A second radiation exposure pathway results from the emission of gamma radiation from uranium decay products contained in the tailings. Gamma radiation emitted from contaminated material delivers an external exposure to the whole body. If the concentration of radon and its decay products is high enough and the exposure time long enough, or if the exposure to direct gamma radiation is long enough, cancers (i.e., excess health effects) may develop in persons living and working at the vicinity properties. 3 refs., 7 tabs

  15. Exploiting the Physicochemical Properties of Dendritic Polymers for Environmental and Biological Applications

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Priyanka; Geitner, Nicholas K.; Sarupria, Sapna; Ke, Pu Chun

    2013-04-07

    In this Perspective we first examine the rich physicochemical properties of dendritic polymers for hosting cations, anions, and polyaromatic hydrocarbons. We then extrapolate these conceptual discussions to the use of dendritic polymers for humic acid antifouling, oil dispersion, copper sensing, and fullerenol remediation. In addition, we review the state-of-the-art of dendrimer research and elaborate on their 10 implications for water purification, environmental remediation, nanomedicine, and energy harvesting.

  16. Safeprops: A Software for Fast and Reliable Estimation of Safety and Environmental Properties for Organic Compounds

    DEFF Research Database (Denmark)

    Jones, Mark Nicholas; Frutiger, Jerome; Abildskov, Jens

    We present a new software tool called SAFEPROPS which is able to estimate major safety-related and environmental properties for organic compounds. SAFEPROPS provides accurate, reliable and fast predictions using the Marrero-Gani group contribution (MG-GC) method. It is implemented using Python...... as the main programming language, while the necessary parameters together with their correlation matrix are obtained from a SQLite database which has been populated using off-line parameter and error estimation routines (Eq. 3-8)....

  17. Environmental impact estimation of municipal solidwaste treatment based on their composition and properties

    Directory of Open Access Journals (Sweden)

    Il'inykh Galina Viktorovna

    2014-02-01

    Full Text Available Municipal solid waste (MSW is a significant environmental and sanitarian problem for urban areas. Different, often alternative, measures are considered in order to reduce the environmental impact of MSW management system, so adequate technique of comparative assessment of their environmental efficiency is needed. The problem is that waste composition, dangerous and organic matter content are often ignored when environmental impacts of MSW management system are calculated. Therefore, an algorithm of environmental impact estimation of municipal solid waste treatment based on their composition and properties is a question of considerable importance.The main difficulty in performing environmental impact calculation in compliance with MSW composition is the evaluation of the emissions per waste unit. Waste component content and biodegradable carbon content in every component are taken into account as basic waste features for emission estimation. Methane generation potential is calculated as a function of biodegradable carbon content.Environmental impacts of waste treatment on manual sorting plant in Yekaterinburg are given as an example. Waste composition analysis was carried out there in 2012. Material flow analysis allowed clarifying mass balance of the process. About 10 % of income waste mass are going out of the waste management system as a recyclables and determine the decreasing of environmental impacts. 1.24 % of biodegradable carbon don’t reach landfills, so it means that production of about ten cubic meters of biogas per ton of income MSW are prevented. When converting this data in money, it results in 47.1 rubles per ton of MSW or about 4.7 million rubles annually.

  18. Risk methodology for geologic disposal of radioactive waste: asymptotic properties of the environmental transport model

    International Nuclear Information System (INIS)

    Helton, J.C.; Brown, J.B.; Iman, R.L.

    1981-02-01

    The Environmental Transport Model is a compartmental model developed to represent the surface movement of radionuclides. The purpose of the present study is to investigate the asymptotic behavior of the model and to acquire insight with respect to such behavior and the variables which influence it. For four variations of a hypothetical river receiving a radionuclide discharge, the following properties are considered: predicted asymptotic values for environmental radionuclide concentrations and time required for environmental radionuclide concentrations to reach 90% of their predicted asymptotic values. Independent variables of two types are used to define each variation of the river: variables which define physical properties of the river system (e.g., soil depth, river discharge and sediment resuspension) and variables which summarize radionuclide properties (i.e., distribution coefficients). Sensitivity analysis techniques based on stepwise regression are used to determine the dominant variables influencing the behavior of the model. This work constitutes part of a project at Sandia National Laboratories funded by the Nuclear Regulatory Commission to develop a methodology to assess the risk associated with geologic disposal of radioactive waste

  19. Nonlinear Dielectric Properties of Yeast Cells Cultured in Different Environmental Conditions

    Science.gov (United States)

    Kawanishi, Gomon; Fukuda, Naoki; Muraji, Masafumi

    The harmonics of the electric current through yeast suspensions, the nonlinear dielectric properties of yeast cells, have particular patterns according to the biological activity of the cells and the measurement of these patterns is a technique for determining the activity of living cells. The concentration of glucose and oxygen in yeast culture medium influences the manifestation of fermentation or respiration of yeast cells. Measurements were made with yeast cells (Saccharomyces cerevisiae) cultured aerobically and anaerobically in sufficient glucose concentration, aerobic fermentation and anaerobic fermentation, and aerobically in limited glucose concentration, respiration. The results showed that the harmonics were barely apparent for yeast cells in aerobic fermentation and respiratory; however, cells in the anaerobic fermentation displayed substantial third and fifth harmonics. We can say that environmental condition affects the yeast cells' nonlinear properties, from another viewpoint, the measurements of the nonlinear properties are available to determine the activity of yeast cells adjusted to the conditions of their cultivation.

  20. Evaluating the fate of organic compounds in the Cameroon ...

    African Journals Online (AJOL)

    Furthermore, a sensitivity analysis was performed to identify the key input parameters. Model simulations indicated significant differences in the fate of the chemicals that could be explained by the variation in physical-chemical properties. The log KOW, emission rate to water (EW), volume of the water compartment (VW) and ...

  1. Environmental Safety of the Use of Major Surfactant Classes in North America

    DEFF Research Database (Denmark)

    Cowan-Ellsberry, Christina; Sanderson, Hans; Belanger, Scott

    2014-01-01

    to the aquatic or sediment environments. This paper also highlights the many years of research that the surfactant and cleaning products industry has supported, as part of their environmental sustainability commitment, to improve environmental tools, approaches, and develop innovative methods appropriate...... to address environmental properties of personal care and cleaning product chemicals, many of which have become approved international standard methods.......This paper brings together over 250 published and unpublished studies on the environmental properties, fate and toxicity of the four major, high volume surfactant classes and relevant feedstocks. The surfactants and feedstocks covered include alcohol sulfate (AS), alcohol ethoxysulfate (AES...

  2. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Nighttime Cloud Optical Microphysical Properties (NCOMP) Environmental Data Record (EDR) from NDE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains a high quality Environmental Data Record (EDR) of nighttime cloud optical and microphysical properties (NCOMP) from the Visible Infrared...

  3. Evaluation of the environmental aging and mechanical properties of the polypropylene/sugarcane bagasse composites

    International Nuclear Information System (INIS)

    Paiva, Rayane Lima de Moura; Mulinari, Daniella Regina

    2013-01-01

    Polypropylene (PP) reinforced with fibers from sugarcane bagasse composites in different proportions were prepared. Also environmental aging was conducted for the composites and their mechanical properties determined. The results showed that chemical treatment caused changes in color and chemical composition of the fibers, removing impurities and amorphous constituents such as lignin and hemicellulose, techniques of FTIR, X-ray diffraction and scanning electron microscopy confirmed these data. Also, it was observed that addition of natural fiber in PP matrix provided an improvement in the mechanical properties materials. The weathering test revealed a slight mass gain after 75 days, but it was clear that the inclusion of fibers has a higher mass gain compared to pure PP. (author)

  4. Fate of nanoparticles during life cycle of polymer nanocomposites

    International Nuclear Information System (INIS)

    Nguyen, T; Pellegrin, B; Bernard, C; Gu, X; Gorham, J M; Stutzman, P; Stanley, D; Shapiro, A; Byrd, E; Hettenhouser, R; Chin, J

    2011-01-01

    Nanoparticles are increasingly used in consumer and structural polymeric products to enhance a variety of properties. Under the influence of environmental factors (e.g., ultraviolet, moisture, temperature) and mechanical actions (e.g., scratching, vibrations, abrasion), nanoparticles could potentially release from the products and thus have negative effects on the environment, health and safety. The fate of nanoparticles in polymer nanocomposites during their exposure to UV environment has been investigated. Epoxy polymer containing multi-walled carbon nanotubes (MWCNTs) and silica nanoparticles were studied. Specially-designed cells containing nanocomposite specimens were irradiated with UV radiation between 295 nm and 400 nm. Chemical degradation, mass loss and surface morphology of the epoxy nanocomposites, and release of nanoparticles were measured. Epoxy containing MWCNTs exposed to UV radiation degraded at a much slower rate than the unfilled epoxy or the epoxy/nanosilica composite. Photodegradation of the matrix resulted in substantial accumulation of nanoparticles on the composite surfaces. Silica nanoparticles were found to release into the environment, but MWCNTs formed a dense network on the composite surface, with no evidence of release even after prolonged exposure. Conceptual models for silica nanoparticle release and MWCNT retention on the surface during UV exposure of nanocomposites are presented.

  5. Understanding the fate and biological effects of Ag- and TiO2-nanoparticles in the environment: The quest for advanced analytics and interdisciplinary concepts

    International Nuclear Information System (INIS)

    Schaumann, Gabriele E.; Philippe, Allan; Bundschuh, Mirco; Metreveli, George; Klitzke, Sondra; Rakcheev, Denis; Grün, Alexandra

    2015-01-01

    Engineered inorganic nanoparticles (EINP) from consumers' products and industrial applications, especially silver and titanium dioxide nanoparticles (NP), are emitted into the aquatic and terrestrial environments in increasing amounts. However, the current knowledge on their environmental fate and biological effects is diverse and renders reliable predictions complicated. This review critically evaluates existing knowledge on colloidal aging mechanisms, biological functioning and transport of Ag NP and TiO 2 NP in water and soil and it discusses challenges for concepts, experimental approaches and analytical methods in order to obtain a comprehensive understanding of the processes linking NP fate and effects. Ag NP undergo dissolution and oxidation with Ag 2 S as a thermodynamically determined endpoint. Nonetheless, Ag NP also undergo colloidal transformations in the nanoparticulate state and may act as carriers for other substances. Ag NP and TiO 2 NP can have adverse biological effects on organisms. Whereas Ag NP reveal higher colloidal stability and mobility, the efficiency of NOM as a stabilizing agent is greater towards TiO 2 NP than towards Ag NP, and multivalent cations can dominate the colloidal behavior over NOM. Many of the past analytical obstacles have been overcome just recently. Single particle ICP-MS based methods in combination with field flow fractionation techniques and hydrodynamic chromatography have the potential to fill the gaps currently hampering a comprehensive understanding of fate and effects also at a low field relevant concentrations. These analytical developments will allow for mechanistically orientated research and transfer to a larger set of EINP. This includes separating processes driven by NP specific properties and bulk chemical properties, categorization of effect-triggering pathways directing the EINP effects towards specific recipients, and identification of dominant environmental parameters triggering fate and effect of

  6. Understanding the fate and biological effects of Ag- and TiO{sub 2}-nanoparticles in the environment: The quest for advanced analytics and interdisciplinary concepts

    Energy Technology Data Exchange (ETDEWEB)

    Schaumann, Gabriele E., E-mail: schaumann@uni-landau.de [Universität Koblenz-Landau, Institute for Environmental Sciences, Group of Environmental and Soil Chemistry, Fortstr. 7, D-76829 Landau (Germany); Philippe, Allan, E-mail: philippe@uni-landau.de [Universität Koblenz-Landau, Institute for Environmental Sciences, Group of Environmental and Soil Chemistry, Fortstr. 7, D-76829 Landau (Germany); Bundschuh, Mirco, E-mail: mirco.bundschuh@slu.se [Universität Koblenz-Landau, Institute for Environmental Sciences, Group of Ecotoxicology and Environment, Fortstr. 7, D-76829 Landau (Germany); Swedish University of Agricultural Sciences, Department of Aquatic Sciences and Assessment, Lennart Hjelms väg 9, SE-75007 Uppsala (Sweden); Metreveli, George, E-mail: metreveli@uni-landau.de [Universität Koblenz-Landau, Institute for Environmental Sciences, Group of Environmental and Soil Chemistry, Fortstr. 7, D-76829 Landau (Germany); Klitzke, Sondra, E-mail: sondra.klitzke@tu-berlin.de [Albert-Ludwigs-Universität Freiburg, Institute of Forest Sciences, Chair of Soil Ecology, 79085 Freiburg i.Br. (Germany); Berlin University of Technology, Institute of Ecology, Department of Soil Science, Ernst-Reuter-Platz 1, D-10587 Berlin (Germany); Rakcheev, Denis, E-mail: rakcheev@uni-landau.de [Universität Koblenz-Landau, Institute for Environmental Sciences, Group of Environmental and Soil Chemistry, Fortstr. 7, D-76829 Landau (Germany); Grün, Alexandra, E-mail: alexg@uni-koblenz.de [Universität Koblenz-Landau, Institute for Integrated Natural Sciences, Dept. of Biology, Universitätsstr. 1, D-56070 Koblenz (Germany); and others

    2015-12-01

    Engineered inorganic nanoparticles (EINP) from consumers' products and industrial applications, especially silver and titanium dioxide nanoparticles (NP), are emitted into the aquatic and terrestrial environments in increasing amounts. However, the current knowledge on their environmental fate and biological effects is diverse and renders reliable predictions complicated. This review critically evaluates existing knowledge on colloidal aging mechanisms, biological functioning and transport of Ag NP and TiO{sub 2} NP in water and soil and it discusses challenges for concepts, experimental approaches and analytical methods in order to obtain a comprehensive understanding of the processes linking NP fate and effects. Ag NP undergo dissolution and oxidation with Ag{sub 2}S as a thermodynamically determined endpoint. Nonetheless, Ag NP also undergo colloidal transformations in the nanoparticulate state and may act as carriers for other substances. Ag NP and TiO{sub 2} NP can have adverse biological effects on organisms. Whereas Ag NP reveal higher colloidal stability and mobility, the efficiency of NOM as a stabilizing agent is greater towards TiO{sub 2} NP than towards Ag NP, and multivalent cations can dominate the colloidal behavior over NOM. Many of the past analytical obstacles have been overcome just recently. Single particle ICP-MS based methods in combination with field flow fractionation techniques and hydrodynamic chromatography have the potential to fill the gaps currently hampering a comprehensive understanding of fate and effects also at a low field relevant concentrations. These analytical developments will allow for mechanistically orientated research and transfer to a larger set of EINP. This includes separating processes driven by NP specific properties and bulk chemical properties, categorization of effect-triggering pathways directing the EINP effects towards specific recipients, and identification of dominant environmental parameters triggering

  7. Mechanical properties of cellulose electro-active paper under different environmental conditions

    International Nuclear Information System (INIS)

    Kim, Heung Soo; Kim, Jaehwan; Jung, Woochul; Ampofo, Joshua; Craft, William; Sankar, Jagannathan

    2008-01-01

    The mechanical properties of cellulose-based electro-active paper (EAPap) are investigated under various environmental conditions. Cellulose EAPap has been discovered as a smart material that can be used as both sensor and actuator. Its advantages include low voltage operation, light weight, low power consumption, biodegradability and low cost. EAPap is made with cellulose paper coated with thin electrodes. EAPap shows a reversible and reproducible bending movement as well as longitudinal displacement under an electric field. However, EAPap is a complex anisotropic material which has not been fully characterized. This study investigates the mechanical properties of cellulose-based EAPap, including Young's modulus, yield strength, ultimate strength and creep, along with orientation directions, humidity and temperature levels. To test the materials in different humidity and temperature levels, a special material testing system was made that can control the testing environmental conditions. The initial Young's modulus of EAPap is in the range of 4–9 GPa, which was higher than that of other polymer materials. Also, the Young's modulus is orientation dependent, which may be associated with the piezoelectricity of EAPap materials. The elastic strength and stiffness gradually decreased when the humidity and temperature were increased. Creep and relaxation were observed under constant stress and strain, respectively. Through scanning electron microscopy, EAPap is shown to exhibit both layered and oriented cellulose macromolecular structures that impact both the elastic and plastic behavior

  8. Methods for assessing environmental impacts of a FUSRAP property-cleanup/interim-storage remedial action

    International Nuclear Information System (INIS)

    Wyman, D.J.

    1982-12-01

    This document provides a description of a property-cleanup/interim-storage action, explanation of how environmental impacts might occur, comprehensive treatment of most potential impacts that might occur as a result of this type of action, discussion of existing methodologies for estimating and assessing impacts, justification of the choice of specific methodologies for use in FUSRAP environmental reviews, assessments of representative impacts (or expected ranges of impacts where possible), suggested mitigation measures, and some key sources of information. The major topical areas covered are physical and biological impacts, radiological impacts, and socioeconomic impacts. Some project-related issues were beyond the scope of this document, including dollar costs, specific accident scenarios, project funding and changes in Congressional mandates, and project management (contracts, labor relations, quality assurance, liability, emergency preparedness, etc.). These issues will be covered in other documents supporting the decision-making process. Although the scope of this document covers property-cleanup and interim-storage actions, it is applicable to other similar remedial actions. For example, the analyses discussed herein for cleanup activities are applicable to any FUSRAP action that includes site cleanup

  9. Critical Evaluation of Environmental, Social and Governance Disclosures of Malaysian Property and Construction Companies

    Directory of Open Access Journals (Sweden)

    Renard Yung Jhien Siew

    2017-06-01

    Full Text Available There is an increasing demand from stakeholders for higher transparency on environmental, social and governance (ESG disclosures. Yet not much is known about the state of sustainability reporting in Malaysia especially in the property and construction industry. This paper aims to fill this gap accordingly. Content analysis of corporate websites, sustainability and annual reports was adopted as the main methodology in this study. Findings show that corporate governance indicators are most reported by Malaysian construction companies compared to other environmental or social indicators. It was also found that details on actual health and safety performance of these companies and the initiatives implemented were largely absent from their reporting. Given the increasing number of rating tools in the capital markets which serve to rank and file companies based on their sustainability disclosures and performance such as the Dow Jones Sustainability Index (DJSI and FTSE4Good Index, it is questionable as to how reliable this can be done for the Malaysian property and construction market. The paper will be useful to construction management practitioners and ESG analysts with a focus on Asian markets.

  10. [The tragic fate of physicians].

    Science.gov (United States)

    Ohry, Avi

    2013-10-01

    Physicians and surgeons were always involved in revolutions, wars and political activities, as well as in various medical humanities. Tragic fate met these doctors, whether in the Russian prisons gulags, German labor or concentration camps, pogroms or at the hands of the Inquisition.

  11. Fate of acetone in water

    Science.gov (United States)

    Rathbun, R.E.; Stephens, D.W.; Shultz, D.J.

    1982-01-01

    The physical, chemical, and biological processes that might affect the concentration of acetone in water were investigated in laboratory studies. Processes considered included volatilization, adsorption by sediments, photodecomposition, bacterial degradation, and absorption by algae and molds. It was concluded that volatilization and bacterial degradation were the dominant processes determining the fate of acetone in streams and rivers. ?? 1982.

  12. Effect of special environmental factors exerted on mechanical properties of CFRP

    International Nuclear Information System (INIS)

    Sonoda, Katsumi; Kaneda, Yoshiharu; Tani, Isao; Nakazaki, Koichi; Enomoto, Junzo; Murayama, Kunihiko; Nakano, Norihiko; Hasegawa, Sumiko; Fukuta, Kenji

    1984-01-01

    This research aims at clarifying the behavior of deterioration of composite materials in the special environment of single factor or compound factors, examining the similarity of the acceleration of deterioration to actual environment and extracting the singularity, and establishing the method of evaluating the properties to withstand environmental effect. In this study, the test on the exposure to various special environments, such as thermal shock, low temperature-high temperature cycle fatigue, electron beam irradiation and heat and vacuum, was carried out. An Instron type testing machine was used, and measurement was carried out at room temperature. The results of the examination of the change of properties due to the change of testing condition by thermal shock test, the electron beam irradiation test at 7.5 x 10 8 rad/h, and the examination of the degasing from CFRP by heat and vacuum test are reported. It was found that bending stress loading method was effective as an accelerated test method because the lowering of residual bending fracture strength was accelerated by thermal shock test. The mechanical properties of CFRP did not change by electron beam irradiation up to 5000 Mrad. The degasing from CFRP under heat and vacuum increased with rising temperature. (Kako, I.)

  13. (Environmental technology)

    Energy Technology Data Exchange (ETDEWEB)

    Boston, H.L.

    1990-10-12

    The traveler participated in a conference on environmental technology in Paris, sponsored by the US Embassy-Paris, US Environmental Protection Agency (EPA), the French Environmental Ministry, and others. The traveler sat on a panel for environmental aspects of energy technology and made a presentation on the potential contributions of Oak Ridge National Laboratory (ORNL) to a planned French-American Environmental Technologies Institute in Chattanooga, Tennessee, and Evry, France. This institute would provide opportunities for international cooperation on environmental issues and technology transfer related to environmental protection, monitoring, and restoration at US Department of Energy (DOE) facilities. The traveler also attended the Fourth International Conference on Environmental Contamination in Barcelona. Conference topics included environmental chemistry, land disposal of wastes, treatment of toxic wastes, micropollutants, trace organics, artificial radionuclides in the environment, and the use biomonitoring and biosystems for environmental assessment. The traveler presented a paper on The Fate of Radionuclides in Sewage Sludge Applied to Land.'' Those findings corresponded well with results from studies addressing the fate of fallout radionuclides from the Chernobyl nuclear accident. There was an exchange of new information on a number of topics of interest to DOE waste management and environmental restoration needs.

  14. State of Academic Knowledge on Toxicity and Biological Fate of Quantum Dots

    Science.gov (United States)

    Pelley, Jennifer L.; Daar, Abdallah S.; Saner, Marc A.

    2009-01-01

    Quantum dots (QDs), an important class of emerging nanomaterial, are widely anticipated to find application in many consumer and clinical products in the near future. Premarket regulatory scrutiny is, thus, an issue gaining considerable attention. Previous review papers have focused primarily on the toxicity of QDs. From the point of view of product regulation, however, parameters that determine exposure (e.g., dosage, transformation, transportation, and persistence) are just as important as inherent toxicity. We have structured our review paper according to regulatory risk assessment practices, in order to improve the utility of existing knowledge in a regulatory context. Herein, we summarize the state of academic knowledge on QDs pertaining not only to toxicity, but also their physicochemical properties, and their biological and environmental fate. We conclude this review with recommendations on how to tailor future research efforts to address the specific needs of regulators. PMID:19684286

  15. Transport and Fate of Volatile Organic Chemical in Soils

    DEFF Research Database (Denmark)

    Petersen, Lis Wollesen

    Recently much attention has been paid to the behavior of volatile organic chemicals (VOCs) in the environment. This is due to the fact that the environmental pollution with these hazardous chemicals has drastically increased during the last decades. The present study is limited to consider...... the transport and fate of VOCs in the gaseous phase, thus contributing to the overall understanding of VOCs behavior in soil, which eventually will facilitate future cleanup....

  16. Evaluate and characterize mechanisms controlling transport, fate, and effects of army smokes in the aerosol wind tunnel: Transport, transformations, fate, and terrestrial ecological effects of hexachloroethane obscurant smokes

    Energy Technology Data Exchange (ETDEWEB)

    Cataldo, D.A.; Ligotke, M.W.; Bolton, H. Jr.; Fellows, R.J.; Van Voris, P.; McVeety, B.D.; Li, Shu-mei W.; McFadden, K.M.

    1989-09-01

    The terrestrial transport, chemical fate, and ecological effects of hexachloroethane (HC) smoke were evaluated under controlled wind tunnel conditions. The primary objectives of this research program are to characterize and assess the impacts of smoke and obscurants on: (1) natural vegetation characteristic of US Army training sites in the United States; (2) physical and chemical properties of soils representative of these training sites; and (3) soil microbiological and invertebrate communities. Impacts and dose/responses were evaluated based on exposure scenarios, including exposure duration, exposure rate, and sequential cumulative dosing. Key to understanding the environmental impacts of HC smoke/obscurants is establishing the importance of environmental parameters such as relative humidity and wind speed on airborne aerosol characteristics and deposition to receptor surfaces. Direct and indirect biotic effects were evaluated using five plant species and two soil types. HC aerosols were generated in a controlled atmosphere wind tunnel by combustion of hexachloroethane mixtures prepared to simulate normal pot burn rates and conditions. The aerosol was characterized and used to expose plant, soil, and other test systems. Particle sizes of airborne HC ranged from 1.3 to 2.1 {mu}m mass median aerodynamic diameter (MMAD), and particle size was affected by relative humidity over a range of 20% to 85%. Air concentrations employed ranged from 130 to 680 mg/m{sup 3}, depending on exposure scenario. Chlorocarbon concentrations within smokes, deposition rates for plant and soil surfaces, and persistence were determined. The fate of principal inorganic species (Zn, Al, and Cl) in a range of soils was assessed.

  17. Integrated fate and toxicity assessment for site contaminants

    International Nuclear Information System (INIS)

    MacDonell, Margaret; Peterson, John; Finster, Molly; Douglas, R.

    2007-01-01

    Understanding the fate and toxicity of environmental contaminants is essential to framing practical management decisions. Forms and bioavailable concentrations often change over time due to natural physical, chemical, and biological processes. For some sites, hundreds of contaminants may be of initial interest, and even small projects can involve a substantial number of contaminants. With multiple assessments common, attention to effectiveness and efficiency is important, and integrating fate and toxicity information provides a valuable way to focus the analyses. Fate assessments help identify what forms may be present where and when, while toxicity information indicates what health effects could result if people were exposed. The integration process is illustrated by an application for the Hanford site, to support long-term management decisions for the cesium and strontium capsules. Fate data, health-based benchmarks, and related toxicity information were effectively combined to indicate performance targets for chemicals and radionuclides identified for capsule leachate that could migrate to groundwater. More than 50 relevant benchmarks and toxicity context were identified for 15 of the 17 study contaminants; values for chronic drinking water exposure provided the common basis for selected indicators. For two chemicals, toxicity information was identified from the scientific literature to guide the performance targets. (authors)

  18. Evaluate and characterize mechanisms controlling transport, fate and effects of army smokes in an aerosol wind tunnel: Transport, transformations, fate and terrestrial ecological effects of fog oil obscurant smokes: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Cataldo, D.A.; Van Voris, P.; Ligotke, M.W.; Fellows, R.J.; McVeety, B.D.; Li, Shu-mei W.; Bolton, H. Jr.; Fredrickson, J.K.

    1989-01-01

    The terrestrial transport, chemical fate, and ecological effects of fog oil (FO) smoke obscurants were evaluated under controlled wind tunnel conditions. The primary objectives of this research program are to characterize and assess the impacts of smoke and obscurants on: (1) natural vegetation characteristic of US Army training sites in the United States; (2) physical and chemical properties of soils representative of these training sites; and (3) soil microbiological and invertebrate communities. Impacts and dose/responses were evaluated based on an exposure scenario, including exposure duration, exposure rate, and sequential cumulative dosing. Key to understanding the environmental impacts of fog oil smoke/obscurants is establishing the importance of environmental parameters, such as relative humidity and wind speed on airborne aerosol characteristics and deposition to receptor surfaces. Direct and indirect biotic effects were evaluated using five plant species and three soil types. 29 refs., 35 figs., 32 tabs.

  19. Specifying pancreatic endocrine cell fates.

    Science.gov (United States)

    Collombat, Patrick; Hecksher-Sørensen, Jacob; Serup, Palle; Mansouri, Ahmed

    2006-07-01

    Cell replacement therapy could represent an attractive alternative to insulin injections for the treatment of diabetes. However, this approach requires a thorough understanding of the molecular switches controlling the specification of the different pancreatic cell-types in vivo. These are derived from an apparently identical pool of cells originating from the early gut endoderm, which are successively specified towards the pancreatic, endocrine, and hormone-expressing cell lineages. Numerous studies have outlined the crucial roles exerted by transcription factors in promoting the cell destiny, defining the cell identity and maintaining a particular cell fate. This review focuses on the mechanisms regulating the morphogenesis of the pancreas with particular emphasis on recent findings concerning the transcription factor hierarchy orchestrating endocrine cell fate allocation.

  20. Ultimate fate of constrained voters

    International Nuclear Information System (INIS)

    Vazquez, F; Redner, S

    2004-01-01

    We examine the ultimate fate of individual opinions in a socially interacting population of leftists, centrists and rightists. In an elemental interaction between agents, a centrist and a leftist can both become centrists or both become leftists with equal rates (and similarly for a centrist and a rightist). However leftists and rightists do not interact. This interaction step between pairs of agents is applied repeatedly until the system can no longer evolve. In the mean-field limit, we determine the exact probability that the system reaches consensus (either leftist, rightist or centrist) or a frozen mixture of leftists and rightists as a function of the initial composition of the population. We also determine the mean time until the final state is reached. Some implications of our results for the ultimate fate in a limit of the Axelrod model are discussed

  1. Ultimate fate of constrained voters

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez, F [Department of Physics, Center for BioDynamics, Boston University, Boston, MA 02215 (United States); Redner, S [Department of Physics, Center for Polymer Studies, Boston University, Boston, MA 02215 (United States)

    2004-09-03

    We examine the ultimate fate of individual opinions in a socially interacting population of leftists, centrists and rightists. In an elemental interaction between agents, a centrist and a leftist can both become centrists or both become leftists with equal rates (and similarly for a centrist and a rightist). However leftists and rightists do not interact. This interaction step between pairs of agents is applied repeatedly until the system can no longer evolve. In the mean-field limit, we determine the exact probability that the system reaches consensus (either leftist, rightist or centrist) or a frozen mixture of leftists and rightists as a function of the initial composition of the population. We also determine the mean time until the final state is reached. Some implications of our results for the ultimate fate in a limit of the Axelrod model are discussed.

  2. Some Properties of Emulsified Asphalt Paving Mixture at Iraqi Environmental Conditions

    Directory of Open Access Journals (Sweden)

    Shakir.A.Al-Mishhadani* Hasan.H.Al-Baid

    2014-04-01

    Full Text Available Cold emulsified asphalt mixture is generally a mix made of emulsified asphalt withaggregate. Emulsified asphalt is manufactured from base asphalt, emulsifier agent and waterwith approximate percentage of 40% to 75% asphalt, 0.1% to 2.5% emulsifier and 25% to60% water plus some minor components. This study aims to use the cold emulsified asphaltmixtures for road construction and maintenance in Iraq as an alternative to the hot asphaltmixtures, due to its economical, practical and environmental advantages. This studyfocusedto test and evaluates the emulsified asphalt material properties to be used as paving mixture.The tested properties of emulsified asphalt mixture were bulk density, air voids, dry Marshallstability, wet Marshall stability, retained Marshall stability, flow tests and compared with thecommon used specification.The results indicate that the emulsified asphalt type cationic slowsetting low viscosity (CSS-1 is very suitable with quartz type of aggregate from Al-Nibaayquarry. From many trial mixes it is found that the best percentages of initial residual bitumencontent to produced adequateresults for coating test ,mixing ,compaction ,curing and Marshallstability were ranged from (2.5%, 3%,3.5%,4% and 4.5%, andthe optimum percentage is(3.5%.Finally it can be conducted that the emulsified asphalt mixture is a suitable alternativemixture to the hot asphalt mixture for road construction and maintenance in Iraq.  

  3. Some Properties of Emulsified Asphalt Paving Mixture at Iraqi Environmental Conditions

    Directory of Open Access Journals (Sweden)

    Shakir.A.Al-Mishhadani

    2014-02-01

    Full Text Available Cold emulsified asphalt mixture is generally a mix made of emulsified asphalt withaggregate. Emulsified asphalt is manufactured from base asphalt, emulsifier agent and waterwith approximate percentage of 40% to 75% asphalt, 0.1% to 2.5% emulsifier and 25% to60% water plus some minor components. This study aims to use the cold emulsified asphaltmixtures for road construction and maintenance in Iraq as an alternative to the hot asphaltmixtures, due to its economical, practical and environmental advantages. This studyfocusedto test and evaluates the emulsified asphalt material properties to be used as paving mixture.The tested properties of emulsified asphalt mixture were bulk density, air voids, dry Marshallstability, wet Marshall stability, retained Marshall stability, flow tests and compared with thecommon used specification.The results indicate that the emulsified asphalt type cationic slowsetting low viscosity (CSS-1 is very suitable with quartz type of aggregate from Al-Nibaayquarry. From many trial mixes it is found that the best percentages of initial residual bitumencontent to produced adequateresults for coating test ,mixing ,compaction ,curing and Marshallstability were ranged from (2.5%, 3%,3.5%,4% and 4.5%, andthe optimum percentage is(3.5%.Finally it can be conducted that the emulsified asphalt mixture is a suitable alternativemixture to the hot asphalt mixture for road construction and maintenance in Iraq.

  4. Environmental effects on electrical properties of Cr-Si-Ni resistive films deposited by magnetron sputtering

    International Nuclear Information System (INIS)

    Zhang Yuqin; Dong Xianping; Wu Jiansheng

    2005-01-01

    The present paper investigated the environmental effects on electrical properties stability and long-term reliability of magnetron sputtered Cr-Si-Ni resistive films in 3.5% NaCl, 0.5 M Na 2 SO 4 and 0.5 M HCl solutions at 25 deg. C, which simulated marine, industrial and acidic environments. The relative resistance change (ΔR/R) for the annealed films revealed that the films had the best electrical properties stability and long-term reliability in industrial environments at 25 deg. C. After immersion in corrosion solutions for 480 h, the value of ΔR/R for the films was only 0.41% in industrial environments, and the values were 0.56 and 1.96% in marine and acidic environments, respectively. The polarization measurements and AES results indicated that the films presented a spontaneous trend to passivation, and could form a dense and stable protective oxide layer (Si oxide) on its surface rapidly that protected the films from further corrosion in three different environments. Furthermore, the formed passive film in industrial environments exhibited much more protective effects on the films than in marine and acidic environments

  5. Facile approach to fabricate waterborne polyaniline nanocomposites with environmental benignity and high physical properties

    Science.gov (United States)

    Wang, Haihua; Wen, Huan; Hu, Bin; Fei, Guiqiang; Shen, Yiding; Sun, Liyu; Yang, Dong

    2017-03-01

    Waterborne polyaniline (PANI) dispersion has got extensive attention due to its environmental friendliness and good processability, whereas the storage stability and mechanical property have been the challenge for the waterborne PANI composites. Here we prepare for waterborne PANI dispersion through the chemical graft polymerisation of PANI into epichlorohydrin modified poly (vinyl alcohol) (EPVA). In comparison with waterborne PANI dispersion prepared through physical blend and in situ polymerisation, the storage stability of PANI-g-EPVA dispersion is greatly improved and the dispersion keeps stable for one year. In addition, the as-prepared PANI-g-EPVA film displays more uniform and smooth morphology, as well as enhanced phase compatibility. PANI is homogeneously distributed in the EPVA matrix on the nanoscale. PANI-g-EPVA displays different morphology at different aniline content. The electrical conductivity corresponds to 7.3 S/cm when only 30% PANI is incorporated into the composites, and then increases up to 20.83 S/cm with further increase in the aniline content. Simultaneously, the tensile strength increases from 35 MPa to 64 MPa. The as-prepared PANI-g-EPVA dispersion can be directly used as the conductive ink or coatings for cellulose fibre paper to prepare flexible conductive paper with high conductivity and mechanical property, which is also suitable for large scalable production.

  6. Dispersion stability and thermophysical properties of environmentally friendly graphite oil–based nanofluids used in machining

    Directory of Open Access Journals (Sweden)

    Yu Su

    2016-01-01

    Full Text Available As environmentally friendly cutting fluids, vegetable-based oil and ester oil are being more and more widely used in metal cutting industry. However, their cooling and lubricating properties are required to be further improved in order to meet more cooling and lubricating challenges in high-efficiency machining. Nanofluids with enhanced heat carrying and lubricating capabilities seem to give a promising solution. In this article, graphite oil–based nanofluids with LB2000 vegetable-based oil and PriEco6000 unsaturated polyol ester as base fluids were prepared by ultrasonically assisted two-step method, and their dispersion stability and thermophysical properties such as viscosity and thermal conductivity were experimentally and theoretically investigated at different ultrasonication times. The results indicate that graphite-PriEco6000 nanofluid showed better dispersion stability, higher viscosity, and thermal conductivity than graphite-LB2000 nanofluid, which made it more suitable for application in high-efficiency machining as coolant and lubricant. The theoretical classical models showed good agreement with the thermal conductivity values of graphite oil–based nanofluids measured experimentally. However, the deviation between the experimental values of viscosity and the theoretical models was relatively big. New empirical correlations were proposed for predicting the viscosity of graphite oil–based nanofluids at various ultrasonication times.

  7. Determination of fluorotelomer alcohols in selected consumer products and preliminary investigation of their fate in the indoor environment

    Science.gov (United States)

    The U.S. Environmental Protection Agency (EPA) has established an ongoing effort to identify the major perfluorocarboxylic acid (PFCA) sources in nonoccupational indoor environments and characterize their transport and fate. This study determined the concentrations of perfluorote...

  8. Global fate of POPs: Current and future research directions

    International Nuclear Information System (INIS)

    Lohmann, Rainer; Breivik, Knut; Dachs, Jordi; Muir, Derek

    2007-01-01

    For legacy and emerging persistent organic pollutants (POPs), surprisingly little is still known in quantitative terms about their global sources and emissions. Atmospheric transport has been identified as the key global dispersal mechanism for most legacy POPs. In contrast, transport by ocean currents may prove to be the main transport route for many polar, emerging POPs. This is linked to the POPs' intrinsic physico-chemical properties, as exemplified by the different fate of hexachlorocyclohexanes in the Arctic. Similarly, our current understanding of POPs' global transport and fate remains sketchy. The importance of organic carbon and global temperature differences have been accepted as key drivers of POPs' global distribution. However, future research will need to understand the various biogeochemical and geophysical cycles under anthropogenic pressures to be able to understand and predict the global fate of POPs accurately. - Future studies into the global fate of POPs will need to pay more attention to the various biogeochemical and anthropogenic cycles to better understand emissions, transport and sinks

  9. Global fate of POPs: Current and future research directions

    Energy Technology Data Exchange (ETDEWEB)

    Lohmann, Rainer [Graduate School of Oceanography, University of Rhode Island, Narragansett, RI 02882-1197 (United States)], E-mail: lohmann@gso.uri.edu; Breivik, Knut [Norwegian Institute for Air Research, PO Box 100, NO-2027 Kjeller (Norway); University of Oslo, Department of Chemistry, PO Box 1033, NO-0315 Oslo (Norway); Dachs, Jordi [Department of Environmental Chemistry, Institute of Chemical and Environmental Research (IIQAB-CSIC), Jordi Girona 18-26, Barcelona 08034 (Spain); Muir, Derek [Aquatic Ecosystem Protection Research Division, Environment Canada, 867 Lakeshore Road, Burlington, ON L7R4A6 (Canada)

    2007-11-15

    For legacy and emerging persistent organic pollutants (POPs), surprisingly little is still known in quantitative terms about their global sources and emissions. Atmospheric transport has been identified as the key global dispersal mechanism for most legacy POPs. In contrast, transport by ocean currents may prove to be the main transport route for many polar, emerging POPs. This is linked to the POPs' intrinsic physico-chemical properties, as exemplified by the different fate of hexachlorocyclohexanes in the Arctic. Similarly, our current understanding of POPs' global transport and fate remains sketchy. The importance of organic carbon and global temperature differences have been accepted as key drivers of POPs' global distribution. However, future research will need to understand the various biogeochemical and geophysical cycles under anthropogenic pressures to be able to understand and predict the global fate of POPs accurately. - Future studies into the global fate of POPs will need to pay more attention to the various biogeochemical and anthropogenic cycles to better understand emissions, transport and sinks.

  10. Ecosystem properties of semiarid savanna grassland in West Africa and its relationship with environmental variability.

    Science.gov (United States)

    Tagesson, Torbern; Fensholt, Rasmus; Guiro, Idrissa; Rasmussen, Mads Olander; Huber, Silvia; Mbow, Cheikh; Garcia, Monica; Horion, Stéphanie; Sandholt, Inge; Holm-Rasmussen, Bo; Göttsche, Frank M; Ridler, Marc-Etienne; Olén, Niklas; Lundegard Olsen, Jørgen; Ehammer, Andrea; Madsen, Mathias; Olesen, Folke S; Ardö, Jonas

    2015-01-01

    The Dahra field site in Senegal, West Africa, was established in 2002 to monitor ecosystem properties of semiarid savanna grassland and their responses to climatic and environmental change. This article describes the environment and the ecosystem properties of the site using a unique set of in situ data. The studied variables include hydroclimatic variables, species composition, albedo, normalized difference vegetation index (NDVI), hyperspectral characteristics (350-1800 nm), surface reflectance anisotropy, brightness temperature, fraction of absorbed photosynthetic active radiation (FAPAR), biomass, vegetation water content, and land-atmosphere exchanges of carbon (NEE) and energy. The Dahra field site experiences a typical Sahelian climate and is covered by coexisting trees (~3% canopy cover) and grass species, characterizing large parts of the Sahel. This makes the site suitable for investigating relationships between ecosystem properties and hydroclimatic variables for semiarid savanna ecosystems of the region. There were strong interannual, seasonal and diurnal dynamics in NEE, with high values of ~-7.5 g C m(-2)  day(-1) during the peak of the growing season. We found neither browning nor greening NDVI trends from 2002 to 2012. Interannual variation in species composition was strongly related to rainfall distribution. NDVI and FAPAR were strongly related to species composition, especially for years dominated by the species Zornia glochidiata. This influence was not observed in interannual variation in biomass and vegetation productivity, thus challenging dryland productivity models based on remote sensing. Surface reflectance anisotropy (350-1800 nm) at the peak of the growing season varied strongly depending on wavelength and viewing angle thereby having implications for the design of remotely sensed spectral vegetation indices covering different wavelength regions. The presented time series of in situ data have great potential for dryland dynamics

  11. Quality assurance of MSWI bottom ash. Environmental properties; Kvalitetssaekring av slaggrus. Miljoemaessiga egenskaper

    Energy Technology Data Exchange (ETDEWEB)

    Flyhammar, Peter [Lund Univ. (Sweden). Engineering Geology

    2006-04-15

    In Sweden, several hundred tonnes of MSWI bottom ash are generated annually at 29 incineration plants for municipal solid waste. So far bottom ash has mainly been disposed in to landfills or used as cover material in landfills or in other construction works at landfills. A few applications of bottom ash in construction works outside landfills have been reported. A large problem for the market of bottom ash and other secondary materials outside Swedish waste treatment plants is the lack of roles and regulations for a non-polluting use. During 2002 Hartlen and Groenholm presented a proposal to a system to assure the quality of bottom ash after homogenization and stabilization. They notice that the leaching of salts and metals to ground water constitutes the largest risk for the environment during use of bottom ash. Therefore, a quality assurance of environmental properties should be based on leaching tests. The aim of this project was to study how the control of environmental properties of bottom ash (at first hand leaching properties) earlier described in e.g. a product information sheet should be worked out. The starting-point has been a control system for bottom ash developed by Sysav. Different leaching tests illustrate however different aspects of the environmental properties, e.g. short-term and long-term leaching. Limit and target values for different variables could affect both the possibilities to use bottom ash as well as the sampling from storage heaps. We have chosen to investigate pH, availability and leached amount and the connection between these variables. the possibilities to use pH or the availability to assess both short-term and longterm leaching properties. how the number of subsamples that should be collected from a storage heap is affected by different control variables and quality requirements. how bottom ash is stabilized by today's storage technology and how the technology could be improved. Our sample test of bottom ash from Swedish

  12. Organic pollutants and heavy metals in rainwater runoff and their fate in the unsaturated soil zone. Final report

    International Nuclear Information System (INIS)

    Grotehusmann, D.; Rohlfing, R.; Weyer, G.; Dittrich, D.; Gowik, P.; Pernak, P.

    1991-01-01

    This bibliographic study is part of the BMFT intergrated project ''Possibilitiis and limits of [ drainage in consederation of the soil and groundwater protection''. Subjects: Environmental relevance and general distribution of organic pollutants; organic pollutants in rain water, soil, and groundwater; fate of organic pollutants in soil; environmental relevance of heavy metals in soil, rain water, and runof; fate of heavy metals in the unsaturated soil rare. (orig./BBR) [de

  13. Effect of carbon nanospheres on algal growth: the influence of physicochemical properties and environmental chemistry

    CSIR Research Space (South Africa)

    Nyembe, DW

    2013-08-01

    Full Text Available Fate and behaviour of ZnO engineered nanoparticles in a simulated domestic wastewater treatment plant E. F. C. Chaúquea, J. N. Zvimbab, J. C. Ngilaa, N. Museeb,c,* aDepartment of Applied Chemistry, UJ, Doornfontein 2028 Johannesburg, South Africa... and toxicity of engineered nanomaterials in aquatic ecosystems, Mary Ondiaka, PhD, US 11:40 –12:00 Statistical modelling approach to derive quantitative nanowastes classification index: estimation of nanomaterials exposure, Loyiso Ntaka, MSc, UJ 12:00 –12...

  14. Quality assurance of MSWI bottom ash. Environmental properties; Kvalitetssaekring av slaggrus. Miljoemaessiga egenskaper

    Energy Technology Data Exchange (ETDEWEB)

    Flyhammar, Peter [Lund Univ. (Sweden). Dept. of Engineering Geology

    2006-04-15

    In Sweden several hundred tonnes of MSWI bottom ash are generated annually at 29 incineration plants for municipal solid waste. So far bottom ash has mainly been disposed in to landfills or used as cover material in landfills or in other construction works at landfills. A few applications of bottom ash in construction works outside landfills have been reported. A large problem for the market of bottom ash and other secondary materials outside Swedish waste treatment plants is the lack of roles and regulations for a non-polluting use. During 2002 Hartlen and Groenholm (HG) presented a proposal to a system to assure the quality of bottom ash after homogenization and stabilization. A quality assurance of environmental properties should be based on leaching tests. The aim of this project was to study how the control of environmental properties of bottom ash earlier described in e.g. a product information sheet should be worked out. The starting-point has been a control system for bottom ash developed by the Sysav company. Different leaching tests illustrate however different aspects of the environmental properties, e.g. short-term and long-term leaching. Limit and target values for different variables could affect both the possibilities to use bottom ash as well as the sampling from storage heaps. We have chosen to investigate: pH, availability and leached amount and the connection between these variables; the possibilities to use pH or the availability to assess both short-term and long term leaching properties; how the number of subsamples that should be collected from a storage heap is affected by different control variables and quality requirements; how bottom ash is stabilized by today's storage technology and how the technology could be improved. Our sample test of bottom ash from Swedish incineration plants indicates that the availability of elements such as Cd, Cu, Cr, Ni, Pb and Zn in bottom ash usually is below Sysav's target values. Extreme values

  15. Environmental properties and microbial communities in coastal waters of Barrow, Alaska from July 11, 2007 to January 14, 2009 (NODC Accession 0073540)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data set consists of basic water column properties of the Beaufort Sea and the Chukchi Sea near Barrow, Alaska. The environmental properties include salinity,...

  16. Hazardous properties and environmental effects of materials used in solar heating and cooling (SHAC) technologies: interim handbook

    Energy Technology Data Exchange (ETDEWEB)

    Searcy, J.Q.

    1978-12-01

    General background informaion related to SHAC systems, how a particular material was chosen for this handbook, and codes and standards are given. Materials are categorized according to their functional use in SHAC systems as follows: (1) heat transfer fluids and fluid treatment chemicals, (2) insulation materials, (3) seals and sealant materials, (4) glazing materials, (5) collector materials, and (6) storage media. The informaion is presented under: general properties, chemical composition, thermal degradation products, and thermoxidative products of some commercial materials; toxic properties and other potential health effects; fire hazard properties; and environmental effects of and disposal methods for SHAC materials. (MHR)

  17. Casein films: effects of formulation, environmental conditions, and addition of citric pectin on the structure and mechanical properties

    Science.gov (United States)

    Thin casein films for food packaging applications reportedly possess good strength and low oxygen permeability, but low water-resistance and elasticity. Modifying and customizing the mechanical properties of the films to target specific behaviors depending on environmental conditions would enable a...

  18. 78 FR 68859 - Draft Environmental Impact Statement for the Proposed Fee-to-Trust Transfer of Property and...

    Science.gov (United States)

    2013-11-15

    ... Environmental Impact Statement for the Proposed Fee-to- Trust Transfer of Property and Subsequent Development of... Agency regarding the Tribe's application for the conveyance into trust of title to lands located in... announces that the DEIS is now available for public review and that public hearings will be held to receive...

  19. Effects of moulding and environmental conditions on the mechanical and surface properties of injection moulded santoprene rubber

    DEFF Research Database (Denmark)

    Islam, Aminul; Ruby, Tobias M.; Jessen, Rikke L.

    the electronics inside from environmental hazards. The sealing ring is injection moulded in Santoprene-a thermoplastic vulcanizate consisting of Polypropelene and highly vulcanized EPDM rubber. The scope of the project was therefore to investigate the properties of Santoprene and make an immediate evaluation...

  20. Environmental Synthesis of Few Layers Graphene Sheets Using Ultrasonic Exfoliation with Enhanced Electrical and Thermal Properties.

    Directory of Open Access Journals (Sweden)

    Monir Noroozi

    Full Text Available In this paper, we report how few layers graphene that can be produced in large quantity with low defect ratio from exfoliation of graphite by using a high intensity probe sonication in water containing liquid hand soap and PVP. It was founded that the graphene powder obtained by this simple exfoliation method after the heat treatment had an excellent exfoliation into a single or layered graphene sheets. The UV-visible spectroscopy, FESEM, TEM, X-ray powder diffraction and Raman spectroscopy was used to analyse the graphene product. The thermal diffusivity of the samples was analysed using a highly accurate thermal-wave cavity photothermal technique. The data obtained showed excellent enhancement in the thermal diffusivity of the graphene dispersion. This well-dispersed graphene was then used to fabricate an electrically conductive polymer-graphene film composite. The results demonstrated that this low cost and environmental friendly technique allowed to the production of high quality layered graphene sheets, improved the thermal and electrical properties. This may find use in the wide range of applications based on graphene.

  1. Secondary materials: Engineering properties, environmental consequences, and social and economic impacts. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Breslin, V.; Reaven, S.; Schwartz, M.; Swanson, L.; Zweig, M.; Bortman, M.; Schubel, J.

    1993-08-01

    This report investigates two secondary materials, plastic lumber made from mixed plastic waste, and cement blocks and structures made with incinerator ash. Engineering properties, environmental impacts, and energy costs and savings of these secondary materials are compared to standard lumber products and cement blocks. Market capacity and social acceptance of plastic lumber and stabilized ash products are analyzed. These secondary materials apparently have potential markets; however, their economic value is primarily that they will not take up landfill space. For plastic lumber and stabilized incinerator ash products, marine and highway construction seem ideal public works applications. Incinerator ash may be suitable to use in seawalls, jetties, fishing reefs, highway barriers, and roadbed applications. Docks, piers, highway sound barriers, parking stops, and park furniture may all be made from plastic lumber. To encourage public acceptance and improve the market potential of secondary materials, these activities could be beneficial: industry should emphasize developing useful, long-lived products; industry and governments should create product performance criteria; government should provide rigorous testing and demonstration programs; and government and industry should cooperate to improve public outreach and educational programs.

  2. On the Environmental Factors Affecting the Structural and Cytotoxic Properties of IAPP Peptides

    Directory of Open Access Journals (Sweden)

    Marianna Flora Tomasello

    2015-01-01

    Full Text Available Pancreatic islets in type 2 diabetes mellitus (T2DM patients are characterized by reduced β-cells mass and diffuse extracellular amyloidosis. Amyloid deposition involves the islet amyloid polypeptide (IAPP, a neuropancreatic hormone cosecreted with insulin by β-cells. IAPP is physiologically involved in glucose homeostasis, but it may turn toxic to β-cells owing to its tendency to misfold giving rise to oligomers and fibrils. The process by which the unfolded IAPP starts to self-assemble and the overall factors promoting this conversion are poorly understood. Other open questions are related to the nature of the IAPP toxic species and how exactly β-cells die. Over the last decades, there has been growing consensus about the notion that early molecular assemblies, notably small hIAPP oligomers, are the culprit of β-cells decline. Numerous environmental factors might affect the conformational, aggregation, and cytotoxic properties of IAPP. Herein we review recent progress in the field, focusing on the influences that membranes, pH, and metal ions may have on the conformational conversion and cytotoxicity of full-length IAPP as well as peptide fragments thereof. Current theories proposed for the mechanisms of toxicity will be also summarized together with an outline of the underlying molecular links between IAPP and amyloid beta (Aβ misfolding.

  3. Improved concrete properties to resist the saline water using environmental by-product

    Directory of Open Access Journals (Sweden)

    Mohamed Anwar

    2013-10-01

    Full Text Available This paper investigates the influence of using environmental by-product materials (silica fume and fly ash in concrete on the chloride ion permeability of concrete. Nine concrete mixtures were designed to have the same degree of workability and air content with water/cementitious material ratio of 0.4. The studied parameters include the main fresh and hardened concrete properties such as slump, air content, unit weight, compressive strength, tensile strength, flexural strength, static Young's modulus, and dynamic elastic modulus. Concrete samples were kept in water for 28 days, then immersed in artificial sea water for 5 months. The total and soluble chloride contents were measured through the concrete using the potentiometric titration analysis. The obtained test results indicated that the use of ternary systems in concrete improved the different characteristics of the product concrete and showed a significant resistance to chloride penetration. The weights of chloride in mix 9 (10% silica fume and 25% fly ash at depths from the concrete surface to 30 mm were less than the weights of control mix 1 (100% ordinary Portland cement by about 60%. Further, the ternary systems can be used in concrete industry with considerable proportions.

  4. The effect of environmental factors on selected mechanical properties of zirconium dioxide

    Science.gov (United States)

    Wirwicki, W.; Andrzejewska, A.; Andryszczyk, M.; Siemianowski, P.

    2018-04-01

    In many centers around the world, research studies are carried out on the mechanical strength of dental materials and glued joints. A literature review shows the variety of testing techniques related to analyzing the strength and durability of the material itself and the glued joints. In dental ceramics, zirconium dioxide is most often used as a base material, and chemically it consists of 97% ZrO2 and 3% Y2O3. This study was to determine the mechanical properties of zirconium dioxide under different environmental conditions. The material is used for the production of dental crowns and tooth bridges in the CAD/CAM technology. This medium is currently one of the most advanced-generation materials used for prosthetic and implant restorations. They were then subjected to a three-point bending test on the Instron ElektroPlus E3000 durability machine. Storage conditions and time have a positive influence on reducing variation in zirconium resistance for active forces and destructive stresses.

  5. Properties of the bentonite from Lieskovec deposit and their possible environmental applications

    International Nuclear Information System (INIS)

    Andrejkovicova, S.

    2008-01-01

    The community increasingly focuses on broader uses of raw materials, occurring in relatively sufficient amounts. Among them, bentonite play very important role in the environmental applications. Results presented herein are related to the yet comprehensively unexplored Fe-rich bentonite from Lieskovec deposit, Central Slovakia. The objective of this study was complex investigation of Lieskovec bentonite deposit. This bentonite was developed from andesitic pyroclastics; the dominant mineral in all the samples is iron-rich montmorillonite, covering 29 to 56 mass % in the samples. The accessory minerals include kaolinite (5-17 mass %), quartz (3-28 mass %), muscovite/illite (3-16 mass %), volcanic glass (6-14 mass %), orthoclase (1-12 mass %), opal (1-8 mass %) and cristobalite (1-3 mass %). Structural Fe(III) is mainly in phyllosilicates accounting for 70 % to 90 % of the total Fe in the unfractionated samples; less than 5 % is Fe(II). The remainder of the Fe is present in oxide and/or oxyhydroxide phases dominated by poorly ordered goethite and hematite with possibly some maghemite. Basic properties of bentonites result from the structure of the smectites. Size fractionation did not lead to pure smectite. Kaolinite and mica were not successfully removed. Quartz and feldspars were dismantled effectively. Non-clay minerals contribution decreased. Smectite content increased after separation up to 75 mass %. Low cation exchange capacities between 35 and 61 meq/100 g are caused also by low magnesium content in the octahedral sheets of montmorillonite, suggesting lower isomorphic Mg for Al substitution in the octahedral sheets of smectite and thus its lower octahedral charge. The main factor influencing CECs is smectite content affecting dominantly also the geotechnical properties. Geotechnical properties of Lieskovec bentonite, such as liquid limit in range 64-80 % and water adsorption by Enslin test 123-265 % were insufficient for utilization in geo-synthetic clay

  6. THE FATE OF TRACE METALS IN A ROTARY KILN INCINERATOR WITH A VENTURI/PACKED COLUMN SCRUBBER - VOLUME I: TECHNICAL RESULTS

    Science.gov (United States)

    A five week series of pilot-scale incineration tests, using a synthetic waste feed, was performed at the Environmental Protection Agency's Incineration Research Facility to evaluate the fate of trace metals fed to a rotary kiln incinerator. Eight tests studied the fate of five ha...

  7. Fate of 14C-labelled compounds in marine environment

    International Nuclear Information System (INIS)

    Kale, S.P.; Raghu, K.; Sherkhane, P.D.; Murthy, N.B.K.

    1999-01-01

    Model ecosystems have played an important role in predicting environmental behavior of agrochemicals. The microcosms used in these studies generally include soil units containing usual biotic components common for that ecosystem. In present studies, scope of two such ecosystems has been extended to study the fate of 14 C-labelled pesticides in marine environment. 14 C-labelled pesticides used in these studies were chlorpyrifos, DDT and HCH. Two systems were developed in laboratory simulating marine environment to study the fate of these pesticides. The first system was developed in an all glass aquarium tank with marine sediments, seawater, clams and algae and is referred to as marine ecosystem. The second system was developed to permit the total 14 C-mass balance studies. It contained marine sediments under moist (60% water holding capacity) or flooded conditions and it is referred to as continuous flow system. Fate of 14 C-DDT was studied in marine ecosystem while degradation of 14 C-chlorpyrifos and 14 C-HCH was studied in continuous flow system. 14 C-DDT did not bioaccumulate in clams while at the end of 60 days 50% of the applied 14 C-activity was present in sediment fraction of marine ecosystem. 14 C-HCH degradation showed about 22-26% mineralization while 45-55% of the applied activity was recovered as organic volatiles. No significant bound residues were formed. 14 C-chorpyrifos underwent considerable degradation in marine environment. TCP was the major degradation product. (author)

  8. Ecosystem properties of semi-arid savanna grassland in West Africa and its relationship to environmental variability

    DEFF Research Database (Denmark)

    Tagesson, Torbern; Fensholt, Rasmus; Guiro, Idrissa

    2015-01-01

    he Dahra field site in Senegal, West Africa, was established in 2002 to monitor ecosystem properties of semiarid savanna grassland and their responses to climatic and environmental change. This article describes the environment and the ecosystem properties of the site using a unique set of in situ......), biomass, vegetation water content, and land-atmosphere exchanges of carbon (NEE) and energy. The Dahra field site experiences a typical Sahelian climate and is covered by coexisting trees (~3% canopy cover) and grass species, characterizing large parts of the Sahel. This makes the site suitable...

  9. Fates of Chemical Elements in Biomass during Its Pyrolysis.

    Science.gov (United States)

    Liu, Wu-Jun; Li, Wen-Wei; Jiang, Hong; Yu, Han-Qing

    2017-05-10

    Biomass is increasingly perceived as a renewable resource rather than as an organic solid waste today, as it can be converted to various chemicals, biofuels, and solid biochar using modern processes. In the past few years, pyrolysis has attracted growing interest as a promising versatile platform to convert biomass into valuable resources. However, an efficient and selective conversion process is still difficult to be realized due to the complex nature of biomass, which usually makes the products complicated. Furthermore, various contaminants and inorganic elements (e.g., heavy metals, nitrogen, phosphorus, sulfur, and chlorine) embodied in biomass may be transferred into pyrolysis products or released into the environment, arousing environmental pollution concerns. Understanding their behaviors in biomass pyrolysis is essential to optimizing the pyrolysis process for efficient resource recovery and less environmental pollution. However, there is no comprehensive review so far about the fates of chemical elements in biomass during its pyrolysis. Here, we provide a critical review about the fates of main chemical elements (C, H, O, N, P, Cl, S, and metals) in biomass during its pyrolysis. We overview the research advances about the emission, transformation, and distribution of elements in biomass pyrolysis, discuss the present challenges for resource-oriented conversion and pollution abatement, highlight the importance and significance of understanding the fate of elements during pyrolysis, and outlook the future development directions for process control. The review provides useful information for developing sustainable biomass pyrolysis processes with an improved efficiency and selectivity as well as minimized environmental impacts, and encourages more research efforts from the scientific communities of chemistry, the environment, and energy.

  10. Fate of a mutation in a fluctuating environment

    Science.gov (United States)

    Cvijović, Ivana; Good, Benjamin H.; Jerison, Elizabeth R.; Desai, Michael M.

    2015-01-01

    Natural environments are never truly constant, but the evolutionary implications of temporally varying selection pressures remain poorly understood. Here we investigate how the fate of a new mutation in a fluctuating environment depends on the dynamics of environmental variation and on the selective pressures in each condition. We find that even when a mutation experiences many environmental epochs before fixing or going extinct, its fate is not necessarily determined by its time-averaged selective effect. Instead, environmental variability reduces the efficiency of selection across a broad parameter regime, rendering selection unable to distinguish between mutations that are substantially beneficial and substantially deleterious on average. Temporal fluctuations can also dramatically increase fixation probabilities, often making the details of these fluctuations more important than the average selection pressures acting on each new mutation. For example, mutations that result in a trade-off between conditions but are strongly deleterious on average can nevertheless be more likely to fix than mutations that are always neutral or beneficial. These effects can have important implications for patterns of molecular evolution in variable environments, and they suggest that it may often be difficult for populations to maintain specialist traits, even when their loss leads to a decline in time-averaged fitness. PMID:26305937

  11. ENM fate in freshwater through adaption of USEtox

    DEFF Research Database (Denmark)

    Miseljic, Mirko; Birkved, Morten; Olsen, Stig Irving

    Engineered nanomaterials (ENMs) have in recent time received substantial attention, both in scientific and consumer circles, as these materials are introduced to a steadily increasing number of consumer products. This has led to environmental concerns on how this new material class behaves...... in the environment, at which concentrations organisms are exposed to the materials and what effects these materials may have on the environment. In relation to metal-oxide engineered nanomaterials (ENMs), as is the general case for ENMs, many environmental aspects are still unknown and/or hence not properly...... scientifically mapped. One approach that has not been given much attention in relation to environmental assessment of ENM, more precisely the fate, exposure and effect modelling of metal-oxide ENMs is the application of adapted characterization modelling (ACM) and hence application of characterisation models...

  12. Review of nitrogen fate models applicable to forest landscapes in the Southern U.S.

    Science.gov (United States)

    D. M. Amatya; C. G. Rossi; A. Saleh; Z. Dai; M. A. Youssef; R. G. Williams; D. D. Bosch; G. M. Chescheir; G. Sun; R. W. Skaggs; C. C. Trettin; E. D. Vance; J. E. Nettles; S. Tian

    2013-01-01

    Assessing the environmental impacts of fertilizer nitrogen (N) used to increase productivity in managed forests is complex due to a wide range of abiotic and biotic factors affecting its forms and movement. Models developed to predict fertilizer N fate (e.g., cycling processes) and water quality impacts vary widely in their design, scope, and potential application. We...

  13. Impacts of soil redistribution on the transport and fate of organic carbon in loess soils

    NARCIS (Netherlands)

    Wang, X.

    2014-01-01

    Soil erosion is an important environmental process leading to loss of topsoil including carbon (C) and nutrients, reducing soil quality and loss of biomass production. So far, the fate of soil organic carbon (SOC) in eroding landscapes is not yet fully understood and remains an important uncertainty

  14. GLOBOX : A spatially differentiated global fate, intake and effect model for toxicity assessment in LCA

    NARCIS (Netherlands)

    Wegener Sleeswijk, Anneke; Heijungs, Reinout

    GLOBOX is a model for the calculation of spatially differentiated LCA toxicity characterisation factors on a global scale. It can also be used for human and environmental risk assessment. The GLOBOX model contains equations for the calculation of fate, intake and effect factors, and equations for

  15. Modeling the fate and transport of bacteria in agricultural and pasture lands using APEX

    Science.gov (United States)

    The Agricultural Policy/Environmental eXtender (APEX) model is a whole farm to small watershed scale continuous simulation model developed for evaluating various land management strategies. The current version, APEX0806, does not have the modeling capacity for fecal indicator bacteria fate and trans...

  16. Ion Exchange Equilibrium and Kinetic Properties of Polyacrylate Films and Applications to Chemical Analysis and Environmental Decontamination

    Science.gov (United States)

    Tanner, Stephen P.

    1997-01-01

    One of the goals of the original proposal was to study how cross-linking affects the properties of an ion exchange material(IEM) developed at Lewis Research Center. However, prior to the start of this work, other workers at LERC investigated the effect of cross-linking on the properties of this material. Other than variation in the ion exchange capacity, the chemical characteristics were shown to be independent of the cross-linking agent, and the degree of cross-linking. New physical forms of the film were developed (film, supported film, various sizes of beads, and powder). All showed similar properties with respect to ion exchange equilibria but the kinetics of ion exchange depended on the surface area per unit mass; the powder form of the IEM exchanging much more rapidly than the other forms. The research performed under this grant was directed towards the application of the IEM to the analysis of metal ions at environmental concentrations.

  17. Mechanical properties of MEMS materials: reliability investigations by mechanical- and HRXRD-characterization related to environmental testing

    Science.gov (United States)

    Bandi, T.; Shea, H.; Neels, A.

    2014-06-01

    The performance and aging of MEMS often rely on the stability of the mechanical properties over time and under harsh conditions. An overview is given on methods to investigate small variations of the mechanical properties of structural MEMS materials by functional characterization, high-resolution x-ray diffraction methods (HR-XRD) and environmental testing. The measurement of the dynamical properties of micro-resonators is a powerful method for the investigation of elasticity variations in structures relevant to microtechnology. X-ray diffraction techniques are used to analyze residual strains and deformations with high accuracy and in a non-destructive manner at surfaces and in buried micro-structures. The influence of elevated temperatures and radiation damage on the performance of resonant microstructures with a focus on quartz and single crystal silicon is discussed and illustrated with examples including work done in our laboratories at CSEM and EPFL.

  18. Phase 2 environmental site investigation procedures and technologies for property transfer and PS and E development

    Science.gov (United States)

    1999-05-01

    The purpose of this project is to provide TxDOT with an improved procedure for conducting environmental site investigations at various stages during transportation infrastructure development. The project seeks to identify modern assessment technologi...

  19. Genesis and properties of wetland soils by VIS-NIR-SWIR as a technique for environmental monitoring.

    Science.gov (United States)

    Demattê, José Alexandre Melo; Horák-Terra, Ingrid; Beirigo, Raphael Moreira; Terra, Fabrício da Silva; Marques, Karina Patrícia Prazeres; Fongaro, Caio Troula; Silva, Alexandre Christófaro; Vidal-Torrado, Pablo

    2017-07-15

    Wetlands are important ecosystems characterized by redoximorphic environments producing typical soil forming processes and organic carbon accumulation. Assessments and management of these areas are dependent on knowledge about soil characteristics and variability. By reflectance spectroscopy, information about soils can be obtained since their spectral behaviors are directly related to their chemical, physical, and mineralogical properties reflecting the pedogenetic processes and environment conditions. Our aims were: (a) to characterize the main soil classes of wetlands regarding their spectral behaviors in VIS-NIR-SWIR (350-2500 nm) and relate them to pedogenesis and environmental conditions, (b) to determine spectral ranges (bands) with greater expression of the main soil properties, (c) to identify spectral variations and similarities between hydromorphic soils from wetlands and other soils under different moisture conditions, and (d) to propose spectral models to quantify some chemical and physical soil properties used as environmental quality indicators. Nine soil profiles from the Pantanal region (Mato Grosso State, Brazil) and one from the Serra do Espinhaço Meridional (Minas Gerais State, Brazil) were investigated. Spectral morphology interpretation allowed identifying horizon differences regarding shape, absorption features and reflectance intensity. Some pedogenetic processes of wetland soils related to organic carbon accumulation and oxide iron variation were identified by spectra. Principal Component Analysis allowed discriminating soils from wetland and outside this area (oxidic environment). Quantification of organic carbon was possible with R 2 of 0.90 and low error. Quantification of clay content was masked by soils with organic carbon content over 2% where it was not possible to quantify with high R 2 and low error both properties when dataset has soil samples with high organic carbon content. By reflectance spectroscopy, important

  20. Mathematical modelling of oil spill fate and transport in the marine environment incorporating biodegradation kinetics of oil droplets

    Science.gov (United States)

    Spanoudaki, Katerina

    2016-04-01

    Oil biodegradation by native bacteria is one of the most important natural processes that can attenuate the environmental impacts of marine oil spills. However, very few numerical models of oil spill fate and transport include biodegradation kinetics of spilled oil. Furthermore, in models where biodegradation is included amongst the oil transformation processes simulated, it is mostly represented as a first order decay process neglecting the effect of several important parameters that can limit biodegradation rate, such as oil composition and oil droplets-water interface. To this end, the open source numerical model MEDSKIL-II, which simulates oil spill fate and transport in the marine environment, has been modified to include biodegradation kinetics of oil droplets dispersed in the water column. MEDSLIK-II predicts the transport and weathering of oil spills following a Lagrangian approach for the solution of the advection-diffusion equation. Transport is governed by the 3D sea currents and wave field provided by ocean circulation models. In addition to advective and diffusive displacements, the model simulates several physical and chemical processes that transform the oil (evaporation, emulsification, dispersion in the water column, adhesion to coast). The fate algorithms employed in MEDSLIK-II consider the oil as a uniform substance whose properties change as the slick weathers, an approach that can lead to reduced accuracy, especially in the estimation of oil evaporation and biodegradation. Therefore MEDSLIK-II has been modified by adopting the "pseudo-component" approach for simulating weathering processes. Spilled oil is modelled as a relatively small number of discrete, non-interacting components (pseudo-components). Chemicals in the oil mixture are grouped by physical-chemical properties and the resulting pseudo-component behaves as if it were a single substance with characteristics typical of the chemical group. The fate (evaporation, dispersion

  1. Variations in Carabidae assemblages across the farmland habitats in relation to selected environmental variables including soil properties

    Directory of Open Access Journals (Sweden)

    Beáta Baranová

    2018-03-01

    Full Text Available The variations in ground beetles (Coleoptera: Carabidae assemblages across the three types of farmland habitats, arable land, meadows and woody vegetation were studied in relation to vegetation cover structure, intensity of agrotechnical interventions and selected soil properties. Material was pitfall trapped in 2010 and 2011 on twelve sites of the agricultural landscape in the Prešov town and its near vicinity, Eastern Slovakia. A total of 14,763 ground beetle individuals were entrapped. Material collection resulted into 92 Carabidae species, with the following six species dominating: Poecilus cupreus, Pterostichus melanarius, Pseudoophonus rufipes, Brachinus crepitans, Anchomenus dorsalis and Poecilus versicolor. Studied habitats differed significantly in the number of entrapped individuals, activity abundance as well as representation of the carabids according to their habitat preferences and ability to fly. However, no significant distinction was observed in the diversity, evenness neither dominance. The most significant environmental variables affecting Carabidae assemblages species variability were soil moisture and herb layer 0-20 cm. Another best variables selected by the forward selection were intensity of agrotechnical interventions, humus content and shrub vegetation. The other from selected soil properties seem to have just secondary meaning for the adult carabids. Environmental variables have the strongest effect on the habitat specialists, whereas ground beetles without special requirements to the habitat quality seem to be affected by the studied environmental variables just little.

  2. Model environmental assessment for a property-cleanup/interim-storage remedial action at a formerly utilized site

    International Nuclear Information System (INIS)

    Merry-Libby, P.

    1982-07-01

    This document has been prepared as a model for the preparation of an Environmental Assessment (EA) for a property-cleanup/interim-storage type of remedial action under the Formerly Utilized Sites Remedial Action Program (FUSRAP) of the US Department of Energy (DOE). For major federal actions significantly affecting the quality of the human environment, an Environmental Impact Statement (EIS) must be prepared to aid DOE in making its decision. However, when it is not clear that an action is major and the impacts are significant, an EA may be prepared to determine whether to prepare an EIS or a finding of no significant impact (FONSI). If it is likely that an action may be major and the impacts significant, it is usually more cost-effective and timely to directly prepare an EIS. If it is likely that a FONSI can be reached after some environmental assessment, as DOE believes may be the case for most property-cleanup/interim-storage remedial actions, preparation of site-specific EAs is an effective means of compliance with NEPA

  3. Fate and effect of hexabromocyclododecane in the environment

    Energy Technology Data Exchange (ETDEWEB)

    Hunziker, R.W.; Friederich, U. [Dow Europe, GmbH, Horgen (Switzerland); MacGregor, J.A.; Desjardins, D. [Wildlife International, Ltd., Easton, MD (United States); Ariano, J. [Great Lakes Chemical Corp., West Lafayette, IN (United States); Gonsior, S.

    2004-09-15

    Hexabromocyclododecane (HBCD) is used as a flame retardant mainly in building insulation composed of extruded or expanded polystyrene foam. A minor use is in flame retardant back-coats of some upholstery textiles. Sales in Europe are estimated to be 9000 t/yr. HBCD has been detected in a number of environmental samples mainly in sediment of urban areas. In a series of acute aquatic toxicity tests, no effect was exhibited at concentrations equal to or below the water solubility of the technical product which consists of ca. 85% {gamma} diastereomer. However, considerable bioconcentration has been reported (log BCF=4). In recent work it has been reported that a shift occurs along the food chain, from {gamma}, the predominant isomer in the technical product, to the {alpha} isomer. HBCD is very hydrophobic and not readily biodegradable, and has been presumed to be persistent in the environment. It is therefore important to have a good understanding of the environmental fate and lifetime of all HBCD isomers. This paper describes new findings on the water solubility of HBCD with respect to its 3 individual isomers, presents results on the acute toxicity in the marine alga Skeletonema costatum at the limit of solubility of all individual isomers and shows first data of an ongoing fate study with {sup 14}C-HBCD where the primary biodegradation of the individual metabolites is differentiated.

  4. Fate and effects of clothianidin in fields using conservation practices.

    Science.gov (United States)

    de Perre, Chloé; Murphy, Tracye M; Lydy, Michael J

    2015-02-01

    Despite the extensive use of the neonicotinoid insecticide clothianidin, and its known toxicity to beneficial insects such as pollinators, little attention has been given to its fate under agricultural field conditions. The present study investigated the fate and toxicity of clothianidin applied every other year as a corn seed-coating at 2 different rates, 0.25 mg/seed and 0.50 mg/seed, in an agricultural field undergoing a corn-soybean annual rotation, and conservation tillage. Concentrations were measured in soil, surface runoff, infiltration, and groundwater from 2011 to 2013. Clothianidin was detected at low concentrations in soil and water throughout the 2-yr corn and soybean rotation. Low and no-tillage had little or no effect on clothianidin concentrations. Laboratory toxicity bioassays were performed on nontarget species, including Daphnia magna, Hyalella azteca, Chironomus dilutus, Pimephales promelas and Eisenia fetida. Risk quotients were calculated from clothianidin concentrations measured in the field and compared with the laboratory toxicity bioassay results to assess the environmental risk of the insecticide. The risk quotient was found to be lower than the level of concern for C. dilutus, which was the most sensitive species tested; therefore, no short-term environmental risk was expected for the species investigated in the present study. © 2014 SETAC.

  5. Arginine and Polyamines Fate in Leishmania Infection

    Science.gov (United States)

    Muxel, Sandra M.; Aoki, Juliana I.; Fernandes, Juliane C. R.; Laranjeira-Silva, Maria F.; Zampieri, Ricardo A.; Acuña, Stephanie M.; Müller, Karl E.; Vanderlinde, Rubia H.; Floeter-Winter, Lucile M.

    2018-01-01

    Leishmania is a protozoan parasite that alternates its life cycle between the sand fly and the mammalian host macrophages, involving several environmental changes. The parasite responds to these changes by promoting a rapid metabolic adaptation through cellular signaling modifications that lead to transcriptional and post-transcriptional gene expression regulation and morphological modifications. Molecular approaches such as gene expression regulation, next-generation sequencing (NGS), microRNA (miRNA) expression profiling, in cell Western blot analyses and enzymatic activity profiling, have been used to characterize the infection of murine BALB/c and C57BL/6 macrophages, as well as the human monocytic cell-lineage THP-1, with Leishmania amazonensis wild type (La-WT) or arginase knockout (La-arg-). These models are being used to elucidate physiological roles of arginine and polyamines pathways and the importance of arginase for the establishment of the infection. In this review, we will describe the main aspects of Leishmania-host interaction, focusing on the arginine and polyamines pathways and pointing to possible targets to be used for prognosis and/or in the control of the infection. The parasite enzymes, arginase and nitric oxide synthase-like, have essential roles in the parasite survival and in the maintenance of infection. On the other hand, in mammalian macrophages, defense mechanisms are activated inducing alterations in the mRNA, miRNA and enzymatic profiles that lead to the control of infection. Furthermore, the genetic background of both parasite and host are also important to define the fate of infection. PMID:29379478

  6. The Spatial Properties of Radical Environmental Organizations in the UK: Do or Die!

    Directory of Open Access Journals (Sweden)

    Zack W Almquist

    Full Text Available Radical environmental groups and their members have a wide and varied agenda which often encompasses both local and global issues. In their efforts to call attention to environmental problems, communicate with like-minded groups, and mobilize support for their activities, radical environmental organizations also produce an enormous amount of text, which can be used to estimate the complex communications and task-based networks that underlie these organizations. Moreover, the tactics employed to garnish attention for these groups' agenda can range from peaceful activities such as information dissemination to violent activities such as fire-bombing buildings. To obtain these varied objectives, radical environmental organizations must harness their networks, which have an important spatial component that structures their ability to communicate, coordinate and act on any given agenda item. Here, we analyze a network built from communications and information provided by the semi-annual "Do or Die" (DoD magazine published in the UK over a 10 year period in the late 1990s and early 2000s. We first employ structural topic model methods to discover violent and nonviolent actors within the larger environmental community. Using this designation, we then compare the spatial structure of these groups, finding that violent groups are especially likely to engage in coordination and/or communication if they are sufficiently close, but exhibit a quickly decreasing probability of interaction over even a few kilometers. Further, violent and nonviolent groups each have a higher probability of coordination with their own group than across groups over even short distances. In these respects, we see that violent groups are especially local in their organization and that their geographic reach is likely very limited. This suggests that nonviolent environmental groups seek each other out over both large and short distances for communication and coordination, but violent

  7. The Spatial Properties of Radical Environmental Organizations in the UK: Do or Die!

    Science.gov (United States)

    Almquist, Zack W; Bagozzi, Benjamin E

    2016-01-01

    Radical environmental groups and their members have a wide and varied agenda which often encompasses both local and global issues. In their efforts to call attention to environmental problems, communicate with like-minded groups, and mobilize support for their activities, radical environmental organizations also produce an enormous amount of text, which can be used to estimate the complex communications and task-based networks that underlie these organizations. Moreover, the tactics employed to garnish attention for these groups' agenda can range from peaceful activities such as information dissemination to violent activities such as fire-bombing buildings. To obtain these varied objectives, radical environmental organizations must harness their networks, which have an important spatial component that structures their ability to communicate, coordinate and act on any given agenda item. Here, we analyze a network built from communications and information provided by the semi-annual "Do or Die" (DoD) magazine published in the UK over a 10 year period in the late 1990s and early 2000s. We first employ structural topic model methods to discover violent and nonviolent actors within the larger environmental community. Using this designation, we then compare the spatial structure of these groups, finding that violent groups are especially likely to engage in coordination and/or communication if they are sufficiently close, but exhibit a quickly decreasing probability of interaction over even a few kilometers. Further, violent and nonviolent groups each have a higher probability of coordination with their own group than across groups over even short distances. In these respects, we see that violent groups are especially local in their organization and that their geographic reach is likely very limited. This suggests that nonviolent environmental groups seek each other out over both large and short distances for communication and coordination, but violent groups tend to be

  8. Mechanical Properties and Durability of Advanced Environmental Barrier Coatings in Calcium-Magnesium-Alumino-Silicate Environments

    Science.gov (United States)

    Miladinovich, Daniel S.; Zhu, Dongming

    2011-01-01

    Environmental barrier coatings are being developed and tested for use with SiC/SiC ceramic matrix composite (CMC) gas turbine engine components. Several oxide and silicate based compositons are being studied for use as top-coat and intermediate layers in a three or more layer environmental barrier coating system. Specifically, the room temperature Vickers-indentation-fracture-toughness testing and high-temperature stability reaction studies with Calcium Magnesium Alumino-Silicate (CMAS or "sand") are being conducted using advanced testing techniques such as high pressure burner rig tests as well as high heat flux laser tests.

  9. the clash of property and environmental rights in the niger delta

    African Journals Online (AJOL)

    RAYAN_

    Property Rights in Economic History: Implications for. Research” (1986) 23 .... mechanisms of collective decision-making, for instance, a leisurely debate among the ..... with Multinational Oil Firms: The Nigerian Experience (Ed-Linform Services,.

  10. Effects of environmental factors and soil properties on topographic variations of soil respiration

    OpenAIRE

    Tamai, K.

    2010-01-01

    Soil respiration rates were measured along different parts of a slope in (a) an evergreen forest with common brown forest soil and (b) a deciduous forest with immature soil. The effects of soil temperature, soil moisture and soil properties were estimated individually, and the magnitudes of these effects in the deciduous and evergreen forests were compared. In the evergreen forest with common brown forest soil, soil properties had the greatest effect on soil respiration rates, followed by soi...

  11. Sequential use of the STICS crop model and of the MACRO pesticide fate model to simulate pesticides leaching in cropping systems.

    Science.gov (United States)

    Lammoglia, Sabine-Karen; Moeys, Julien; Barriuso, Enrique; Larsbo, Mats; Marín-Benito, Jesús-María; Justes, Eric; Alletto, Lionel; Ubertosi, Marjorie; Nicolardot, Bernard; Munier-Jolain, Nicolas; Mamy, Laure

    2017-03-01

    The current challenge in sustainable agriculture is to introduce new cropping systems to reduce pesticides use in order to reduce ground and surface water contamination. However, it is difficult to carry out in situ experiments to assess the environmental impacts of pesticide use for all possible combinations of climate, crop, and soils; therefore, in silico tools are necessary. The objective of this work was to assess pesticides leaching in cropping systems coupling the performances of a crop model (STICS) and of a pesticide fate model (MACRO). STICS-MACRO has the advantage of being able to simulate pesticides fate in complex cropping systems and to consider some agricultural practices such as fertilization, mulch, or crop residues management, which cannot be accounted for with MACRO. The performance of STICS-MACRO was tested, without calibration, from measurements done in two French experimental sites with contrasted soil and climate properties. The prediction of water percolation and pesticides concentrations with STICS-MACRO was satisfactory, but it varied with the pedoclimatic context. The performance of STICS-MACRO was shown to be similar or better than that of MACRO. The improvement of the simulation of crop growth allowed better estimate of crop transpiration therefore of water balance. It also allowed better estimate of pesticide interception by the crop which was found to be crucial for the prediction of pesticides concentrations in water. STICS-MACRO is a new promising tool to improve the assessment of the environmental risks of pesticides used in cropping systems.

  12. In Silico Prediction of Physicochemical Properties of Environmental Chemicals Using Molecular Fingerprints and Machine Learning

    Science.gov (United States)

    There are little available toxicity data on the vast majority of chemicals in commerce. High-throughput screening (HTS) studies, such as those being carried out by the U.S. Environmental Protection Agency (EPA) ToxCast program in partnership with the federal Tox21 research progra...

  13. Emerging organic contaminants in sludges. Analysis, fate and biological treatment

    Energy Technology Data Exchange (ETDEWEB)

    Vicent, Teresa [Univ. Autonoma de Barcelona, Bellaterra (Spain). Chemical Engineering Dept.; Eljarrat, Ethel [IDAEA-CSIC, Barcelona (Spain). Dept. of Environmental Chemistry; Caminal, Gloria [IQAC-CSIC, Barcelona (Spain). Grupo de biocatalisis Aplicada y biodegradacion; Barcelo, Damia (eds.) [IDAEA-CSIC, Barcelona (Spain). Dept. of Environmental Chemistry; Girona Univ. (Spain). Catalan Inst. for Water Research

    2013-07-01

    A comprehensive review. Written by experts. Richly illustrated. There are a growing number of new chemicals in the environment that represent an ascertained or potential risk. Many of them can be found in sewage sludge and are the subject of this volume. Experts in the field highlight their occurrence and fate, risks of biosolid use, advanced chemical analysis methods, and degradation techniques with a special focus on biodegradation using fungi. In the final chapter conclusions and trends are offered as a point of departure for future studies. The double-disciplinary approach combining environmental analysis and engineering makes the book a valuable and comprehensive source of information for a broad audience, such as environmental chemists and engineers, biotechnologists, ecotoxicologists and professionals responsible for waste and water management.

  14. Cell volume change through water efflux impacts cell stiffness and stem cell fate

    NARCIS (Netherlands)

    Guo, Ming; Pegoraro, Adrian F.; Mao, Angelo; Zhou, Enhua H.; Arany, Praveen R.; Han, Yulong; Burnette, Dylan T.; Jensen, Mikkel H.; Kasza, Karen E.; Moore, Jeffrey R.; Mackintosh, Frederick C.; Fredberg, Jeffrey J.; Mooney, David J.; Lippincott-Schwartz, Jennifer; Weitz, David A.

    2017-01-01

    Cells alter their mechanical properties in response to their local microenvironment; this plays a role in determining cell function and can even influence stem cell fate. Here, we identify a robust and unified relationship between cell stiffness and cell volume. As a cell spreads on a substrate, its

  15. Environmental dynamic, business strategy, and financial performance: An empirical study of Indonesian property and real estate industry

    Directory of Open Access Journals (Sweden)

    Imam Wahyudi

    2013-04-01

    Full Text Available Firm’s strategic orientation involves synchronizing environmental dynamics, corporate strategy and capital structure in order to achieve firm performance targets. The co-alignment model used successfully in the hospitality industry might be used in a wider context as a framework in explain- ing these relationships simultaneously. Using the data of public firms in Indonesia during the pe- riod of 1996-2010, we found that co-alignment model can be implemented in property and real estate industry as well as in hospitality industry.

  16. Environmental effect on the mechanical properties of commingled-yarn-based carbon fibre/polyamide 6 composites

    DEFF Research Database (Denmark)

    Raghavalu Thirumalai, Durai Prabhakaran; Toftegaard, Helmuth Langmaack

    2014-01-01

    The main objective of this experimental investigation was to evaluate the changes from accelerated ageing on selected properties of carbon fibre/polyamide 6 composites based on hybrid yarns. In this study, two types of mechanical tests were performed to measure the environmental influence...... on the material properties. They are three-point bending to measure the flexural strength and stiffness, and short beam three-point bending to measure the interlaminar shear strength. The 10-mm-thick quasi-isotropic carbon fibre/polyamide 6 composites with 52% volume fraction of carbon fibre to be tested were...... temperature. The interlaminar shear strength values also drop to about 75% at both −45 and 115. Extreme temperatures and long-time exposure to humidity of quasi-isotropic carbon fibre/polyamide 6 laminates can thus reduce the bending stiffness and strength by up to 35% and the interlaminar shear strength...

  17. Effects of environmental factors and soil properties on topographic variations of soil respiration

    Directory of Open Access Journals (Sweden)

    K. Tamai

    2010-03-01

    Full Text Available Soil respiration rates were measured along different parts of a slope in (a an evergreen forest with common brown forest soil and (b a deciduous forest with immature soil. The effects of soil temperature, soil moisture and soil properties were estimated individually, and the magnitudes of these effects in the deciduous and evergreen forests were compared. In the evergreen forest with common brown forest soil, soil properties had the greatest effect on soil respiration rates, followed by soil moisture and soil temperature. These results may be explained by the fact that different soil properties matured within different environments. It can be argued that the low soil respiration rates in the low parts of the slope in the evergreen forest resulted from soil properties and not from wet soil conditions. In the deciduous forest, soil respiration rates were more strongly affected by soil moisture and soil temperature than by soil properties. These effects were likely due to the immaturity of the forest soil.

  18. Mechanical and thermal properties of environmentally friendly composites derived from sugar palm tree

    International Nuclear Information System (INIS)

    Sahari, J.; Sapuan, S.M.; Zainudin, E.S.; Maleque, M.A.

    2013-01-01

    Highlights: ► We successfully developed biocomposites derived from sugar palm tree. ► The addition of SPF improve the mechanical properties of biocomposites. ► The thermal stability of biocomposites increase with increasing of SPF. ► The water absorption of biocomposites decrease with increasing of SPF. ► We investigate the morphological fracture through scanning electron microscopy. - Abstract: The aim of this paper is to study the effect of fibre content on mechanical properties, water absorption behaviour and thermal properties of sugar palm fibre (SPF) reinforced plasticized sugar palm starch (SPF/SPS) biocomposites. The biocomposites were prepared with different amounts of fibres (i.e. 10%, 20% and 30% by weight percent) by using glycerol as plasticizer for the starch. The mechanical properties of plasticized SPS improved with the incorporation of fibres. Fibre loading also increased the thermal stability of the biocomposite in this investigation. Water uptake and moisture content of SPF/SPS biocomposites decreased with the incorporation of fibres, which is due to better interfacial bonding between the matrix and fibres as well as the hindrance to absorption caused by the fibres. Fractographic studies through scanning electron microscopy showed homogeneous distribution of fibres and matrix with good adhesion which play an important role in improving the mechanical properties of biocomposites

  19. Corrosive effect of environmental change on selected properties of polymer composites

    Science.gov (United States)

    Markovičová, L.; Zatkalíková, V.

    2017-11-01

    The development of composite materials and the related design and manufacturing technologies is one of the most important advances in the history of materials. Composites are multifunctional materials having unprecedented mechanical and physical properties that can be tailored to meet the requirements of a particular application. Ageing is also important and it is defined as the process of deterioration of engineering materials resulting from the combined effects of atmospheric radiation, heat, oxygen, water, micro-organisms and other atmospheric factors. The present article deals with monitoring the changes in the mechanical properties of composites with polymer matrix. The composite was formed from the PA matrix and glass fibers (GF). The composite contains 10, 20 and 30 % of glass fibers. The mechanical properties were evaluated on samples of the composite before and after UV radiation on the sample. Light microscopy was evaluated distribution of glass fibers in the polymer matrix and the presence of cracks caused by UV radiation.

  20. AFM studies of environmental effects on nanomechanical properties and cellular structure of human hair

    International Nuclear Information System (INIS)

    Bhushan, Bharat; Chen, Nianhuan

    2006-01-01

    Characterization of cellular structure and physical and mechanical properties of hair are essential to develop better cosmetic products and advance biological and cosmetic science. Although the morphology of the cellular structure of human hair has been traditionally investigated using scanning electron microscopy and transmission electron microscopy, these techniques provide limited capability to in situ study of the physical and mechanical properties of human hair in various environments. Atomic force microscopy (AFM) overcomes these problems and can be used for characterization in ambient conditions without requiring specific sample preparations and surface treatment. In this study, film thickness, adhesive forces and effective Young's modulus of various hair surfaces were measured at different environments (humidity and temperature) using force calibration plot technique with an AFM. Torsional resonance mode phase contrast images were also taken in order to characterize the morphology and cellular structure changes of human hair at different humidity. The correlation between the nanomechanical properties and the cellular structure of hair is discussed

  1. Human mammary progenitor cell fate decisions are productsof interactions with combinatorial microenvironments

    DEFF Research Database (Denmark)

    LaBarge, Mark A.; Nelson, Celeste M.; Villadsen, René

    2009-01-01

    factors, ECM, and other cells, as well as physical properties of the ECM. To understand regulation of fate decisions, therefore, would require a means of understanding carefully choreographed combinatorial interactions. Here we used microenvironment protein microarrays to functionally identify...... combinations of cell-extrinsic mammary gland proteins and ECM molecules that imposed specific cell fates on bipotent human mammary progenitor cells.Micropatterned cell culture surfaces were fabricated to distinguish between the instructive effects of cell-cell versus cell-ECM interactions, as well...

  2. Tensile properties of human collagen fibrils and fascicles are insensitive to environmental salts

    DEFF Research Database (Denmark)

    Svensson, René B; Hassenkam, Tue; Grant, Colin A

    2010-01-01

    loading direction of tendon is along its longitudinal axis. Thus, in this study, we focus on the tensile mechanical properties of two hierarchical levels from human patellar tendon, namely: individual collagen fibrils and fascicles. Investigations on collagen fibrils and fascicles were made at pH 7...... was observed at the highest phosphate-buffered saline concentration for both the fibrils and fascicles, indicating a stabilizing effect of ionic screening, but changes were much less than reported for radial compression. Due to the small magnitude of the effects, the tensile mechanical properties of collagen...

  3. The Idea of Sustainable Development to Reconcile the Environmental and Intellectual Property Protection of Plants

    DEFF Research Database (Denmark)

    Gebreselassie, Abeba T.

    2010-01-01

    Sustainable development calls for environmental sustainability, economic sustainability and socio-political sustainability.The concept of sustainable development is enshrined in a number of global and regional treaties, declarations, and reports such as the Brundtland Commission Report, the Rio...... Declaration, Agenda 21, the Millennium Development Goals[MDGs], the Johannesburg Declaration and the Johannesburg Plan of Implementation, and the 2000 Cotonou Agreement between African, Caribbean and Pacific States and the European Union [the Cotonou Agreement]. The purpose of this Article is to integrate...... in the following sections shows, the successful implementation of the CBD partly depends on the cooperation of other states and that there is thus a need for an international integration of environmental protection into development laws, policies and programs. Second, the intersection between the CBD...

  4. U02 pellets surface properties and environmental conditions effects on the wet adsorption

    International Nuclear Information System (INIS)

    Junqueira, Fabio da S.; Carnaval, Joao Paulo R.

    2013-01-01

    Angra power plants fuels are made bye en riche uranium dioxide (UO 2 ) pellets which are assembled inside metal tubes. These tubes are welded and arranged in order to perform the final product, the fuel assembly. The UO 2 pellets have a specified humidity tolerance designed to comply with security and performance requirements when working under operating conditions in the reactor. This work intends to verify the pellet opened porosity and the environmental conditions (relative humidity and temperature) influence on the wet adsorption by UO 2 pellet. The work was done in 2 parts: Firstly, pallets groups from 3 opened porosity levels were tested under a fixed relative humidity, temperature and time. In the second part of the work, the most critical pallet group upon wet adsorption was tested under different relative humidity and temperature conditions, regarding design of experiments. The opened porosity and environmental conditions tests allowed the evolution of the wet adsorption by the UO 2 pallet. (author)

  5. Prediction of long-term properties of by-products - Technical and environmental properties in roads; Foerutsaegelse av laangtidsegenskaper hos restprodukter - Teknik och miljoe i vaegar

    Energy Technology Data Exchange (ETDEWEB)

    Arm, Maria; Suer, Pascal; Arvidsson, Haakan; Lindqvist, Jan-Erik; Frogner-Kockum, Paul; Larsson, Lennart; Toomvaeli, Cecilia

    2008-12-15

    In Sweden, use of industrial by-products is still hindered by concern for their long-term properties. This report describes a three-year research project aiming to: - Identify the key processes of ageing related to the usefulness of by-products in roads; - investigate the consequences of these processes for technical and environmental properties of the by-products, and - propose a method for accelerated ageing to predict the long-term properties. The project has compared naturally aged samples of two by-products used as sub-bases in existing asphalt paved roads with samples of fresh by-products from producers' piles. Steel slag of electric arc furnace type and municipal solid waste incinerator (MSWI) bottom ash was chosen. The samples were thoroughly characterized in order to identify which ageing processes had been crucial. The following properties were studied: grain size distribution, water content, compaction properties, deformation properties according to cyclic load triaxial tests, mineralogy and micro structure according to SEM and XRD, chemical composition, pH and leaching properties. For the bottom ash also organic content and electric conductivity was studied. Furthermore the pH was mapped in both roads and the conductivity was mapped in the bottom ash road. The working hypothesis was that ageing processes lead to changes in pH, effective particle size and mineralogy, which in turn determine leaching, stiffness and stability of the material. The test results confirmed that the pavement edge material is ageing faster than the road centre material is. In addition it was concluded that: - Steel slag from the pavement edge showed traces of carbonation and leaching processes, whereas slag from the road centre was identical to fresh slag. - Bottom ash from the pavement edge was more aged than bottom ash from the road centre. However, no difference in pH was found, instead the differences were said to be caused by differences in water exposure. - Water

  6. Evaluation, maintenance and improvement of biodiversity for environmental protection and crop nutritional properties

    OpenAIRE

    Fusaro, Silvia

    2015-01-01

    Biodiversity is expected to be an assurance for agroecosystem resilience because it seems fundamental to preserve basic ecosystem services (ES). To examine in depth these topics, the present research aims: a) to evaluate, in real farms, the environmental sustainability by measuring the efficiency of some key ES in agroecosystems with different management; b) to search for relationships among biodiversity groups and ES and c) to explore the existence of correlations between different bioindica...

  7. Comparative fate of an organochlorine, chlordecone, and a related compound, chlordecone-5b-hydro, in soils and plants.

    Science.gov (United States)

    Clostre, Florence; Cattan, Philippe; Gaude, Jean-Marie; Carles, Céline; Letourmy, Philippe; Lesueur-Jannoyer, Magalie

    2015-11-01

    We address the problem of the comparative environmental fate of a pesticide, chlordecone (CLD), and a related compound, chlordecone-5b-hydro (CLD-5b-hydro). We used a large database including data from two types of contaminated volcanic soils, andosol and nitisol, and thirteen crops grown in the French West Indies in historically polluted soils. We performed in-depth statistical analysis of the effect of different parameters (soil type, crop, organ, etc.) on the ratio of CLD-5b-hydro to CLD in both soils and plants. The environmental fate of the two compounds differed depending on the type of soil. Proportionally, more CLD-5b-hydro than CLD was measured in nitisols than in andosols. Compared to CLD, we also found a preferential transfer of CLD-5b-hydro from the soil to the plant. Finally, mobilization of the two compounds differed according to the species of crop but also within the plant, with increasing ratios from the roots to the top of the plant. The properties of the compound played a key role in the underlying processes. Because CLD-5b-hydro is more soluble in water and has a lower K(ow) than CLD, CLD-5b-hydro (1) was more easily absorbed from soils by plants, (2) was less adsorbed onto plant tissues and (3) was transported in greater quantities through the transpiration stream. Due to the amounts of CLD-5b-hydro we measured in some plant parts such as cucurbit fruits, an assessment of the toxicity of this CLD monodechlorinated product is recommended. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Environmental Chemistry Methods (ECM) Index - N

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with N as the first character.

  9. Environmental Chemistry Methods (ECM) Index - K

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with K as the first character.

  10. Environmental Chemistry Methods (ECM) Index - M

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with M as the first character.

  11. Environmental Chemistry Methods (ECM) Index - R

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with R as the first character.

  12. Environmental Chemistry Methods (ECM) Index - G

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with G as the first character.

  13. Environmental Chemistry Methods (ECM) Index - O

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with O as the first character.

  14. Environmental Chemistry Methods (ECM) Index - S

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with S as the first character.

  15. Environmental Chemistry Methods (ECM) Index - B

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with B as the first character.

  16. Environmental Chemistry Methods (ECM) Index - C

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with C as the first character.

  17. Environmental Chemistry Methods (ECM) Index - F

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with F as the first character.

  18. Environmental Chemistry Methods (ECM) Index - P

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with P as the first character.

  19. Environmental Chemistry Methods (ECM) Index - L

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with L as the first character.

  20. Environmental Chemistry Methods (ECM) Index - H

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with H as the first character.

  1. Environmental Chemistry Methods (ECM) Index - I

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with I as the first character.

  2. Environmental Chemistry Methods (ECM) Index - Z

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with Z as the first character.

  3. Environmental Chemistry Methods (ECM) Index - A

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with A as the first character.

  4. Environmental Chemistry Methods (ECM) Index - E

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with E as the first character.

  5. Environmental Chemistry Methods (ECM) Index - T

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with T as the first character.

  6. Environmental Chemistry Methods (ECM) Index - D

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with D as the first character.

  7. Environmental Chemistry Methods (ECM) Index - Q

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with Q as the first character.

  8. Environmental and management impacts on temporal variability of soil hydraulic properties

    Science.gov (United States)

    Bodner, G.; Scholl, P.; Loiskandl, W.; Kaul, H.-P.

    2012-04-01

    Soil hydraulic properties underlie temporal changes caused by different natural and management factors. Rainfall intensity, wet-dry cycles, freeze-thaw cycles, tillage and plant effects are potential drivers of the temporal variability. For agricultural purposes it is important to determine the possibility of targeted influence via management. In no-till systems e.g. root induced soil loosening (biopores) is essential to counteract natural soil densification by settling. The present work studies two years of temporal evolution of soil hydraulic properties in a no-till crop rotation (durum wheat-field pea) with two cover crops (mustard and rye) having different root systems (taproot vs. fibrous roots) as well as a bare soil control. Soil hydraulic properties such as near-saturated hydraulic conductivity, flow weighted pore radius, pore number and macroporosity are derived from measurements using a tension infiltrometer. The temporal dynamics are then analysed in terms of potential driving forces. Our results revealed significant temporal changes of hydraulic conductivity. When approaching saturation, spatial variability tended to dominate over the temporal evolution. Changes in near-saturated hydraulic conductivity were mainly a result of changing pore number, while the flow weighted mean pore radius showed less temporal dynamic in the no-till system. Macroporosity in the measured range of 0 to -10 cm pressure head ranged from 1.99e-4 to 8.96e-6 m3m-3. The different plant coverage revealed only minor influences on the observed system dynamics. Mustard increased slightly the flow weighted mean pore radius, being 0.090 mm in mustard compared to 0.085 mm in bare soil and 0.084 mm in rye. Still pore radius changes were of minor importance for the overall temporal dynamics. Rainfall was detected as major driving force of the temporal evolution of structural soil hydraulic properties at the site. Soil hydraulic conductivity in the slightly unsaturated range (-7 cm to -10

  9. Properties of biochar derived from wood and high-nutrient biomasses with the aim of agronomic and environmental benefits.

    Directory of Open Access Journals (Sweden)

    Rimena R Domingues

    Full Text Available Biochar production and use are part of the modern agenda to recycle wastes, and to retain nutrients, pollutants, and heavy metals in the soil and to offset some greenhouse gas emissions. Biochars from wood (eucalyptus sawdust, pine bark, sugarcane bagasse, and substances rich in nutrients (coffee husk, chicken manure produced at 350, 450 and 750°C were characterized to identify agronomic and environmental benefits, which may enhance soil quality. Biochars derived from wood and sugarcane have greater potential for improving C storage in tropical soils due to a higher aromatic character, high C concentration, low H/C ratio, and FTIR spectra features as compared to nutrient-rich biochars. The high ash content associated with alkaline chemical species such as KHCO3 and CaCO3, verified by XRD analysis, made chicken manure and coffee husk biochars potential liming agents for remediating acidic soils. High Ca and K contents in chicken manure and coffee husk biomass can significantly replace conventional sources of K (mostly imported in Brazil and Ca, suggesting a high agronomic value for these biochars. High-ash biochars, such as chicken manure and coffee husk, produced at low-temperatures (350 and 450°C exhibited high CEC values, which can be considered as a potential applicable material to increase nutrient retention in soil. Therefore, the agronomic value of the biochars in this study is predominantly regulated by the nutrient richness of the biomass, but an increase in pyrolysis temperature to 750°C can strongly decrease the adsorptive capacities of chicken manure and coffee husk biochars. A diagram of the agronomic potential and environmental benefits is presented, along with some guidelines to relate biochar properties with potential agronomic and environmental uses. Based on biochar properties, research needs are identified and directions for future trials are delineated.

  10. The Fate of Exomoons when Planets Scatter

    Science.gov (United States)

    Kohler, Susanna

    2018-03-01

    Four examples of close-encounter outcomes: a) the moon stays in orbit around its host, b) the moon is captured into orbit around its perturber, c) and d) the moon is ejected from the system from two different starting configurations. [Adapted from Hong et al. 2018]Planet interactions are thought to be common as solar systems are first forming and settling down. A new study suggests that these close encounters could have a significant impact on the moons of giant exoplanets and they may generate a large population of free-floating exomoons.Chaos in the SystemIn the planetplanet scattering model of solar-system formation, planets are thought to initially form in closely packed systems. Over time, planets in a system perturb each other, eventually entering an instability phase during which their orbits cross and the planets experience close encounters.During this scattering process, any exomoons that are orbiting giant planets can be knocked into unstable orbits directly by close encounters with perturbing planets. Exomoons can also be disturbed if their host planets properties or orbits change as a consequence of scattering.Led by Yu-Cian Hong (Cornell University), a team of scientists has now explored the fate of exomoons in planetplanet scattering situations using a suite of N-body numerical simulations.Chances for SurvivalHong and collaborators find that the vast majority roughly 80 to 90% of exomoons around giant planets are destabilized during scattering and dont survive in their original place in the solar system. Fates of these destabilized exomoons include:moon collision with the star or a planet,moon capture by the perturbing planet,moon ejection from the solar system,ejection of the entire planetmoon system from the solar system, andmoon perturbation onto a new heliocentric orbit as a planet.Unsurprisingly, exomoons that have close-in orbits and those that orbit larger planets are the most likely to survive close encounters; as an example, exomoons on

  11. Effects of Environmental Surface Modification Methods on Physical Properties of Hemp Fibers

    Directory of Open Access Journals (Sweden)

    Nigar MERDAN

    2017-11-01

    Full Text Available In this study, hemp fibers have been pre-treated with laccase enzyme in different concentrations (1%, 2% and 3% w/v for different durations using conventional, ultrasonic energy and microwave energy methods. Weight loss (%, tensile strength, elongation (%, whiteness (%, and surface topography (SEM properties of pre-treated hemp fibers were investigated. After processing with laccase enzyme, the energy consumptions of these three methods were compared. Best results have been obtained in 20 minutes with the conventional method, 5 minutes with the ultrasonic energy method, and 1 minute with the microwave energy method. With laccase enzyme, microwave treated hemp fibers were improved after 3 minutes treatment. SEM results have also proved the improved physical properties and color changes due to the rough surface structure. DOI: http://dx.doi.org/10.5755/j01.ms.23.4.17469

  12. Final Environmental Assessment for the Transfer of the Mukilteo Tank Farm Property Snohomish County, Washington

    Science.gov (United States)

    2012-10-01

    terms of level of service (LOS). The LOS is a qualitative description of traffic flow based on such factors as speed, travel time, delay, and...south to Whidbey Island on the north. It provides one basic lane in each direction of travel ; however, in the vicinity of the Mukilteo Tank Farm...Wildlife, 2006). 3.7.2 Ground Water The Mukilteo Tank Farm Property overlies the Intercity Plateau Aquifer, an unconsolidated sand and gravel aquifer

  13. Casein Films: The Effects of Formulation, Environmental Conditions and the Addition of Citric Pectin on the Structure and Mechanical Properties

    Directory of Open Access Journals (Sweden)

    Laetitia M. Bonnaillie

    2014-07-01

    Full Text Available Thin casein films for food packaging applications reportedly possess good strength and low oxygen permeability, but low elasticity and high sensitivity to moisture. Modifying the films to target specific behaviors depending on environmental conditions can enable a variety of commercial applications for casein-based films. The mechanical properties of solvent-cast (15% solids calcium-caseinate/glycerol films (CaCas:Gly ratio of 3:1 were characterized as a function of processing and environmental conditions, including film thickness, solution formulation and ambient humidity (from 22% to 70% relative humidity (RH at ~20 °C. At constant RH, the elongation at break (EAB had a strong positive dependence on the film thickness. When RH increased, the tensile strength (TS and modulus (E decreased approximately linearly, while EAB increased. From 0.05% to 1% (w/w of citric pectin (CP was then incorporated into CaCas/Gly films following seven different formulations (mixing sequences, to alter the protein network and to evaluate the effects of CP on the tensile properties of CaCas/Gly/CP films. At constant film thickness and ~60% RH, the addition of 0.1% or 1.0% CP to the films considerably increased or decreased EAB, TS and E in different directions and to different extents, depending on the formulation, while optical micrographs also showed vastly differing network configurations, suggesting complex formulation- and stoichiometry-dependent casein-pectin interactions within the dried films. Depending on the desired film properties and utilization conditions, pectin may be a useful addition to casein film formulations for food packaging applications.

  14. Fate of Pyrethroids in Farmland Ponds

    DEFF Research Database (Denmark)

    Mogensen, B. B.; Sørensen, P. B.; Stuer-Lauridsen, F.

    Pyrethroids constitute a group of widely used insecticides, which are toxic to aquatic organisms. This report presents the results from a 2-year study of the fate of pyrethroids in ponds, i.e. their distribution in the water column, the sediment and the surface microlayer respectively. The measur......Pyrethroids constitute a group of widely used insecticides, which are toxic to aquatic organisms. This report presents the results from a 2-year study of the fate of pyrethroids in ponds, i.e. their distribution in the water column, the sediment and the surface microlayer respectively...

  15. Environmental radon

    International Nuclear Information System (INIS)

    Majumdar, S.K.; Schmalz, R.F.; Miller, E.W.

    1990-01-01

    This book covers many aspects of environmental radon, including: historical perspectives; occurrence and properties; detection, measurement, and mitigation, radon and health; and political, economic, and legislative impacts

  16. Influence of environmental properties on macrobenthos in the northwest Indian shelf.

    Science.gov (United States)

    Jayaraj, K A; Jayalakshmi, K V; Saraladevi, K

    2007-04-01

    The paper deals with the standing stock of macrobenthic infauna and associated environmental factors influencing the benthic community in the shelf region of the northwest Indian coast. The data were collected onboard FORV Sagar Sampada during the winter monsoon (January-February, 2003) to understand the community structure and the factors influencing the benthic distribution. The environmental parameters, sediment characteristics and macrobenthic infauna were collected at 26 stations distributed in the depths between 30 and 200 m extending from Mormugao to Porbander. Total benthic abundance was high in lower depths (50-75 m), and low values noticed at 30 m depth contour was peculiar. Polychaetes were the dominant group and were more abundant in shallow and middle depths with moderate organic matter, clay and relatively high dissolved oxygen. On the other hand crustaceans and molluscs were more abundant in deeper areas having sandy sediment and low temperature. High richness and diversity of whole benthic groups observed in deeper depths counter balanced the opposite trend shown by polychaete species. Generally benthos preferred medium grain sized texture with low organic matter and high organic matter had an adverse effect especially on filter feeders. Deposit feeding polychaetes dominated in shallow depths while carnivore species in the middle depths. Ecologically, benthos were controlled by a combination of factors such as temperature, salinity, dissolved oxygen, sand and organic matter and no single factor could be considered as an ecological master factor.

  17. Release Properties and Electrochemical Characterization of Encapsulated Corrosion Inhibitors for Environmentally Friendly Smart Coatings

    Science.gov (United States)

    Pearman, B. P.; Calle, L. M.; Zhang, X.; Li, W.; Buhrow, J. W.; Johnsey, M. N.; Montgomery, E. L.; Fitzpatrick, L.; Surma, J. M.

    2015-01-01

    The NASA Kennedy Space Center's Corrosion Technology Lab at the Kennedy Space Center in Florida, U.S.A. has been developing multifunctional smart coatings based on the microencapsulation of environmentally friendly corrosion indicators, inhibitors and self-healing agents. This allows for the incorporation of autonomous corrosion control functionalities, such as corrosion detection and inhibition as well as the self-healing of mechanical damage, into coatings. This paper presents technical details on the characterization of inhibitor-containing particles and their corrosion inhibitive effects using electrochemical and mass loss methods. Three organic environmentally friendly corrosion inhibitors were encapsulated in organic microparticles that are compatible with desired coatings. The total inhibitor content and the release of one of the inhibitors from the microparticles in basic solution was measured. Particles with inhibitor contents of up 60 wt% were synthesized. Fast release, for immediate corrosion protection, as well as long-term release for continued protection, was observed. The inhibition efficacy of the inhibitors, both as the pure materials and in microparticles, on carbon steel was evaluated. Polarization curves and mass loss measurements showed that, in the case of 2MBT, its corrosion inhibition effectiveness was greater when it was delivered from microparticles.

  18. Effect of Environmental Degradation on Mechanical Properties of Kenaf/Polyethylene Terephthalate Fiber Reinforced Polyoxymethylene Hybrid Composite

    Directory of Open Access Journals (Sweden)

    Mohamad Zaki Abdullah

    2013-01-01

    Full Text Available The main objective of this research is to investigate the effect of environmental degradation on the mechanical properties of kenaf/PET fiber reinforced POM hybrid composite. Kenaf and PET fibers were selected as reinforcements because of their good mechanical properties and resistance to photodegradation. The test samples were produced by compression molding. The samples were exposed to moisture, water spray, and ultraviolet penetration in an accelerated weathering chamber for 672 hours. The tensile strength of the long fiber POM/kenaf (80/20 composite dropped by 50% from 127.8 to 64.8 MPa while that of the hybrid composite dropped by only 2% from 73.8 to 72.5 MPa. This suggests that the hybrid composite had higher resistance to tensile strength than the POM/kenaf composite. Similarly, the results of flexural and impact strengths also revealed that the hybrid composite showed less degradation compared to the kenaf fiber composite. The results of the investigation revealed that the hybrid composite had better retention of mechanical properties than that of the kenaf fiber composites and may be suitable for outdoor application in the automotive industry.

  19. The PdBI arcsecond whirlpool survey (PAWS): Environmental dependence of giant molecular cloud properties in M51

    International Nuclear Information System (INIS)

    Colombo, Dario; Hughes, Annie; Schinnerer, Eva; Meidt, Sharon E.; Leroy, Adam K.; Pety, Jérôme; Dumas, Gaëlle; Schuster, Karl F.; Dobbs, Clare L.; García-Burillo, Santiago; Thompson, Todd A.; Kramer, Carsten

    2014-01-01

    Using data from the PdBI Arcsecond Whirlpool Survey (PAWS), we have generated the largest extragalactic giant molecular cloud (GMC) catalog to date, containing 1507 individual objects. GMCs in the inner M51 disk account for only 54% of the total 12 CO(1-0) luminosity of the survey, but on average they exhibit physical properties similar to Galactic GMCs. We do not find a strong correlation between the GMC size and velocity dispersion, and a simple virial analysis suggests that ∼30% of GMCs in M51 are unbound. We have analyzed the GMC properties within seven dynamically motivated galactic environments, finding that GMCs in the spiral arms and in the central region are brighter and have higher velocity dispersions than inter-arm clouds. Globally, the GMC mass distribution does not follow a simple power-law shape. Instead, we find that the shape of the mass distribution varies with galactic environment: the distribution is steeper in inter-arm region than in the spiral arms, and exhibits a sharp truncation at high masses for the nuclear bar region. We propose that the observed environmental variations in the GMC properties and mass distributions are a consequence of the combined action of large-scale dynamical processes and feedback from high-mass star formation. We describe some challenges of using existing GMC identification techniques for decomposing the 12 CO(1-0) emission in molecule-rich environments, such as M51's inner disk.

  20. Influence of Environmental Pollution on Leaf Properties of Urban Plane Trees, Platanus orientalis L.

    Science.gov (United States)

    Pourkhabbaz, Alireza; Rastin, Nayerah; Olbrich, Andrea; Langenfeld-Heyser, Rosemarie

    2010-01-01

    To investigate whether leaves of plane trees (Platanus orientalis) are damaged by traffic pollution, trees from a megacity (Mashhad, Iran) and a rural area were investigated. Soil and air from the urban centre showed enrichment of several toxic elements, but only lead was enriched in leaves. Leaf size and stomata density were lower at the urban site. At the urban site leaf surfaces were heavily loaded by dust particles but the stomata were not occluded; the cuticle was thinner; other anatomical properties were unaffected suggesting that plane trees can cope with traffic exhaust in megacities. PMID:20577871

  1. Comparison of chemical and physical properties of carbon blacks for sampling and analysis of environmental pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Mastrogiacomo, A.R.; Ottaviani, M.F.; Pierini, E.; Cangiotti, M.; Mangani, F. [Ist. di Scienze Chimiche ' ' Fabrizio Bruner' ' dell' Univ. degli Studi di Urbino, Urbino (Italy); Mauro, M. [Dipt. di Chimica dell' Univ. degli Studi di Firenze, Firenze (Italy)

    2002-03-01

    Some of the most commonly employed carbon blocks (Carbograph 1, 2, 4, 5 from Lara and Carbopack X from Supelco), were evaluated by the BET surface characterization method for pore size distribution, porosity and specific surface. This information is often incomplete as furnished by manufacturers and is needed for a deeper understanding of carbon adsorption properties in chromatography. The data on surface characterization were obtained before and after graphitisation treatment (except for Carbopack X which could not be obtained in non-graphitized form). The nature of the active sites present on these carbons was investigated by BET analysis, atomic absorption and FT-IR. (orig.)

  2. Mechanical properties and environmental effects of epoxy resins in the neat state and in composites

    International Nuclear Information System (INIS)

    Yang, C.M.P.

    1984-01-01

    The dynamic mechanical properties of graphite fiber reinforced, epoxy matrix composite laminates subjected to loading perpendicular to the plane of lamination and of neat epoxy resin are reported. The centrosymmetric deformation (CSD) test geometry provides an accurate and convenient test mode for the study of the viscoelastic behavior of very stiff graphite-epoxy laminates. It is found that the in-phase and out-of-phase stiffness superpose to form master curves covering a frequency range of 12 decades. By a suitable scaling procedure of the master curves, it is found that the in-phase stiffness has the same shape and the out-of-phase has the same dispersion for all laminates irrespective of the stacking sequence. The dispersion characteristics of in-situ and neat resin epoxy were nearly identical, but with the neat resin having a lower glass-transition temperature. The graphite/epoxy composites and neat resin epoxy have been shown to be sensitive to hygrothermal environment. For postcured specimens the plasticization and inhomogeneous swelling effects due to the moisture absorbed are found to be reversible, in the sense that the initially dry properties of the laminate are recovered after redrying the wet specimen. On the other hand, for as cured specimens, the plasticization and inhomogeneous swelling effects are found to be irreversible under the same hygrothermal environment

  3. Impact of long-term land application of broiler litter on environmentally related soil properties

    Energy Technology Data Exchange (ETDEWEB)

    Kingery, W.L. [Mississippi State Univ., MS (United States); Wood, C.W.; Mullins, G.L. [Auburn Univ., AL (United States)] [and others

    1994-01-01

    The largest portion of Alabama`s rapidly growing poultry industry is geographically concentrated in the Sand Mountain region of northern Alabama. The result is that large amounts of waste are applied to relatively small areas of agricultural soils. A study was conducted to determine the effects of long-term broiler waste (litter) application on environmentally related soil conditions in the region. The region has an average annual rainfall of 1325 mm, which is evenly distributed throughout the year, a thermic temperature regime, and soils in the region are of the Ultisol order. In each of four major broiler-producing counties, three pairs of sites consisting of long-term (15-28 yr) littered and nonlittered fields on matching soil series and maintained under perennial tall fescue (Festuca arundinacea Schreb.) were sampled. Soil cores were taken to 3 m or lithic contact and depth-incremented samples (0-15, 15-30, and each subsequent 30-cm interval) were analyzed for organic C, total N, NO{sub 3}-N, pH, electrical conductivity, and acid-extractable P, K, Ca, Mg, Co, and Zn. Litter application increased organic C and total N to depths of 15 and 30 cm, respectively, as compared with nonlittered soils, whereas pH was 0.5 units higher to a depth of 60 cm under littered soils. Significant accumulation of NO{sub 3}N was found in littered soils to or near bedrock. Extractable P concentrations in littered soils were more than six times greater than in nonlittered soils to a depth of 60 cm. Elevated levels of extractable K, Ca, and Mg to depths greater than 60 cm also were found as a result of long-term litter use. Extractable Cu and Zn had accumulated in littered soils to a depth of 45 cm. These findings indicate that long-term land application of broiler litter, at present rates, has altered soil chemical conditions and has created a potential for adverse environmental impacts in the Sand Mountain region of Alabama. 43 refs., 6 figs., 3 tabs.

  4. Concentrations and fate of decamethylcyclopentasiloxane (D(5)) in the atmosphere.

    Science.gov (United States)

    McLachlan, Michael S; Kierkegaard, Amelie; Hansen, Kaj M; van Egmond, Roger; Christensen, Jesper H; Skjøth, Carsten A

    2010-07-15

    Decamethylcyclopentasiloxane (D(5)) is a volatile compound used in personal care products that is released to the atmosphere in large quantities. Although D(5) is currently under consideration for regulation, there have been no field investigations of its atmospheric fate. We employed a recently developed, quality assured method to measure D(5) concentration in ambient air at a rural site in Sweden. The samples were collected with daily resolution between January and June 2009. The D(5) concentration ranged from 0.3 to 9 ng m(-3), which is 1-3 orders of magnitude lower than previous reports. The measured data were compared with D(5) concentrations predicted using an atmospheric circulation model that included both OH radical and D(5) chemistry. The model was parametrized using emissions estimates and physical chemical properties determined in laboratory experiments. There was good agreement between the measured and modeled D(5) concentrations. The results show that D(5) is clearly subject to long-range atmospheric transport, but that it is also effectively removed from the atmosphere via phototransformation. Atmospheric deposition has little influence on the atmospheric fate. The good agreement between the model predictions and the field observations indicates that there is a good understanding of the major factors governing D(5) concentrations in the atmosphere.

  5. Black carbon mixing state impacts on cloud microphysical properties: effects of aerosol plume and environmental conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ching, Ping Pui; Riemer, Nicole; West, Matthew

    2016-05-27

    Black carbon (BC) is usually mixed with other aerosol species within individual aerosol particles. This mixture, along with the particles' size and morphology, determines the particles' optical and cloud condensation nuclei properties, and hence black carbon's climate impacts. In this study the particle-resolved aerosol model PartMC-MOSAIC was used to quantify the importance of black carbon mixing state for predicting cloud microphysical quantities. Based on a set of about 100 cloud parcel simulations a process level analysis framework was developed to attribute the response in cloud microphysical properties to changes in the underlying aerosol population ("plume effect") and the cloud parcel cooling rate ("parcel effect"). It shows that the response of cloud droplet number concentration to changes in BC emissions depends on the BC mixing state. When the aerosol population contains mainly aged BC particles an increase in BC emission results in increasing cloud droplet number concentrations ("additive effect"). In contrast, when the aerosol population contains mainly fresh BC particles they act as sinks for condensable gaseous species, resulting in a decrease in cloud droplet number concentration as BC emissions are increased ("competition effect"). Additionally, we quantified the error in cloud microphysical quantities when neglecting the information on BC mixing state, which is often done in aerosol models. The errors ranged from -12% to +45% for the cloud droplet number fraction, from 0% to +1022% for the nucleation-scavenged black carbon (BC) mass fraction, from -12% to +4% for the effective radius, and from -30% to +60% for the relative dispersion.

  6. Low-Dimensional Material: Structure-Property Relationship and Applications in Energy and Environmental Engineering

    Science.gov (United States)

    Xiao, Hang

    In the past several decades, low-dimensional materials (0D materials, 1D materials and 2D materials) have attracted much interest from both the experimental and theoretical points of view. Because of the quantum confinement effect, low-dimensional materials have exhibited a kaleidoscope of fascinating phenomena and unusual physical and chemical properties, shedding light on many novel applications. Despite the enormous success has been achieved in the research of low-dimensional materials, there are three fundamental challenges of research in low-dimensional materials: 1) Develop new computational tools to accurately describe the properties of low-dimensional materials with low computational cost. 2) Predict and synthesize new low-dimensional materials with novel properties. 3) Reveal new phenomenon induced by the interaction between low-dimensional materials and the surrounding environment. In this thesis, atomistic modelling tools have been applied to address these challenges. We first developed ReaxFF parameters for phosphorus and hydrogen to give an accurate description of the chemical and mechanical properties of pristine and defected black phosphorene. ReaxFF for P/H is transferable to a wide range of phosphorus and hydrogen containing systems including bulk black phosphorus, blue phosphorene, edge-hydrogenated phosphorene, phosphorus clusters and phosphorus hydride molecules. The potential parameters were obtained by conducting global optimization with respect to a set of reference data generated by extensive ab initio calculations. We extended ReaxFF by adding a 60° correction term which significantly improved the description of phosphorus clusters. Emphasis was placed on the mechanical response of black phosphorene with different types of defects. Compared to the nonreactive SW potential of phosphorene, ReaxFF for P/H systems provides a significant improvement in describing the mechanical properties of the pristine and defected black phosphorene, as well

  7. A facile route to controlled synthesis of Co3O4 nanoparticles and their environmental catalytic properties

    International Nuclear Information System (INIS)

    Dong Yuming; He Kun; Yin Lin; Zhang Aimin

    2007-01-01

    Using ammonia and Co(CH 3 COO) 2 ·4H 2 O as starting materials, a facile and surfactant-free route to controlled synthesis of Co 3 O 4 nanoparticles was proposed. Co 3 O 4 nanoparticles with average sizes of 3.5, 6, 11, 19 and 70 nm were obtained through adjusting the ethanol amount in the solvent (the ratio of ethanol to water) or the concentration of raw materials. In this process, the presence of enough O 2 was crucial for the formation of pure Co 3 O 4 phase. The environmental catalytic properties of as-obtained Co 3 O 4 nanoparticles were investigated. The results indicated their remarkable catalysis for ozonation degradation of phenol, which denoted a promising application as catalyst in waste-water treatment

  8. Anti-biofilm potential of phenolic acids: the influence of environmental pH and intrinsic physico-chemical properties.

    Science.gov (United States)

    Silva, Sara; Costa, Eduardo M; Horta, Bruno; Calhau, Conceição; Morais, Rui M; Pintado, M Manuela

    2016-09-13

    Phenolic acids are a particular group of small phenolic compounds which have exhibited some anti-biofilm activity, although the link between their activity and their intrinsic pH is not clear. Therefore, the present work examined the anti-biofilm activity (inhibition of biomass and metabolic activity) of phenolic acids in relation to the environmental pH, as well as other physico-chemical properties. The results indicate that, while Escherichia coli was not inhibited by the phenolic acids, both methicillin resistant Staphylococcus aureus and methicillin resistant Staphylococcus epidermidis were susceptible to the action of all phenolic acids, with the pH playing a relevant role in the activity: a neutral pH favored MRSE inhibition, while acidic conditions favored MRSA inhibition. Some links between molecular polarity and size were associated only with their potential as metabolic inhibitors, with the overall interactions hinting at a membrane-based mechanism for MRSA and a cytoplasmic effect for MRSE.

  9. Transformation and distribution processes governing the fate and behaviour of nanomaterials in the environment: an overview

    DEFF Research Database (Denmark)

    Hansen, Steffen Foss; Hartmann, Nanna B.; Baun, Anders

    2015-01-01

    assessment. Chemical fate modelling is one approach to fill this gap within a short time frame. To ensure the reliability of predicted environmental concentrations informed choices are needed during model formulation and development. A major knowledge gap, hampering the further development of such model...... present in the environment. Specific nanomaterials are used as case studies to illustrate these processes. Key environmental processes are identified and ranked and key knowledge gaps are identified, feeding into the longer-term goal of improving the existing models for predicted environmental...

  10. Environmental fate of pesticides applied on coffee crops in ...

    African Journals Online (AJOL)

    Veronica Umukoro

    behavior of the compound in the soil and volatilization, leaching, superficial runoff and .... chemical reaction, advective flow and nondiffusive transport rate equations into fugacity ... R: Gas constant (8,314 Pa.m³/mol K). T: Absolute temperature ...

  11. Environmental fate and effects of the lampricide TFM: A review

    Science.gov (United States)

    Hubert, T.D.

    2003-01-01

    Use of 3-trifluoromethyl-4-nitrophenol (TFM) is limited geographically to the Great Lakes basin where it is the principal agent used in control of the sea lamprey (Petromyzon marinus). It is clear from available data that TFM has effects on the environment, but the effects reported are transient. Individual organisms and aquatic communities return to pretreatment conditions after lampricide treatments have concluded. TFM is not persistent, is detoxified, and presents minimal long-term toxicological risk. TFM is relatively nontoxic to mammals. Treatment levels do not pose a threat to wildlife. However, TFM is an estrogen agonist and additional testing to define the nature and magnitude of this effect will likely be required. Because stream treatments are done on 3 to 5 year cycles, and exposures are limited to approximately 12 h, minimal risk to aquatic organisms is expected.

  12. Aquatic Environmental Contamination: The fate of Asejire Lake in ...

    African Journals Online (AJOL)

    A study of catfish from Asejire Lake (located at the outskirt of Ibadan, a major city in Oyo State of South-West Nigeria) was carried out to assess the level of contamination due to effluents from various industries in Ibadan, Oyo State particularly the Nigerian Bottling Company, Plc (NBC). The industrial site is located close to ...

  13. Environmental fate and transport analysis with compartment modeling

    National Research Council Canada - National Science Library

    Little, Keith W

    2012-01-01

    .... Discussing various modeling issues in a single volume, this text provides an introduction to a specific numerical modeling technique called the compartment approach and offers a practical user's guide to the GEM...

  14. Environmental Transport and Fate Process Descriptors for Propellant Compounds

    Science.gov (United States)

    2006-06-01

    rate of 1.2 mL/min. The RP-HPLC used a mercury lamp UV detector at 254 nm. The calibration range was 0.2 to 19.2 parts per million with a reporting... phytoremediation of perchlorate- contaminated water. In Perchlorate in the environment, ed. E. T. Urbansky, 219- 229. New York, NY: Kluwer Academic/Plenum...identification of metabolic products in Myriophyllum aquaticum. International Journal of Phytoremediation 1:97-107. Swann, R. L., D. A. Laskowski, P. J. McCall

  15. Environmental chemistry, ecotoxicity, and fate of lambda-cyhalothrin.

    Science.gov (United States)

    He, Li-Ming; Troiano, John; Wang, Albert; Goh, Kean

    2008-01-01

    Lambda-cyhalothrin is a pyrethroid insecticide used for controlling pest insects in agriculture, public health, and in construction and households. Lambda-cyhalothrin is characterized by low vapor pressure and a low Henry's law constant but by a high octanol-water partition coefficient (K(ow)) and high water-solid-organic carbon partition coefficient (K(oc)) values. Lambda-cyhalothrin is quite stable in water at pH lambda-cyhalothrin is relatively photostable under natural irradiation, with a half-life > 3 wk, its photolysis process is fast under UV irradiation, with a half-life lambda-cyhalothrin in aquatic ecosystems depends on the nature of system components such as suspended solids (mineral and organic particulates) and aquatic organisms (algae, macrophytes, or aquatic animals). Lambda-cyhalothrin residues dissolved in water decrease rapidly if suspended solids and/or aquatic organisms are present because lambda-cyhalothrin molecules are strongly adsorbed by particulates and plants. Adsorbed lambda-cyhalothrin molecules show decreased degradation rates because they are less accessible to breakdown than free molecules in the water column. On the other hand, lambda-cyhalothrin adsorbed to suspended solids or bottom sediments may provide a mechanism to mitigate its acute toxicity to aquatic organisms by reducing their short-term bioavailability in the water column. The widespread use of lambda-cyhalothrin has resulted in residues in sediment, which have been found to be toxic to aquatic organisms including fish and amphipods. Mitigation measures have been used to reduce the adverse impact of lambda-cyhalothrin contributed from agricultural or urban runoff. Mitigation may be achieved by reducing the quantity of runoff and suspended solid content in runoff through wetlands, detention ponds, or vegetated ditches.

  16. Environmental-Fate Patterns for Perfluoroalkylates and their Precursors

    Science.gov (United States)

    Two sites with elevated concentrations of perfluoroalkylates (PFAs) and fluorotelomer alcohols (FTOHs) were studied: 1) agricultural fields near Decatur, AL on which sewage sludge had been applied; and 2) the Conasauga River system near Dalton, GA where treated sewage effluent is...

  17. Evaluation of the Environmental Fate of Munition Compounds in Soil.

    Science.gov (United States)

    1979-06-01

    temperature in- duction furnace. Nitrate Water samples were analyzed for nitrate (NO:T) by a Dion -X System Ten ion chromatograph. Nitrite Water samples...moderately well drained Celins , somewhat poorly drained Crosby and Conover, and very poorly drained Kokomo form a drainage sequence with the

  18. Assessing the Role of Environmental Factors on Baltic Cod Recruitment, a Complex Adaptive System Emergent Property

    Directory of Open Access Journals (Sweden)

    Dionysis Krekoukiotis

    2016-07-01

    Full Text Available For decades, fish recruitment has been a subject of intensive research with stock–recruitment models commonly used for recruitment prediction often only explaining a small fraction of the inter-annual recruitment variation. The use of environmental information to improve our ability to predict recruitment, could contribute considerably to fisheries management. However, the problem remains difficult because the mechanisms behind such complex relationships are often poorly understood; this in turn, makes it difficult to determine the forecast estimation robustness, leading to the failure of some relationships when new data become available. The utility of machine learning algorithms such as artificial neural networks (ANNs for solving complex problems has been demonstrated in aquatic studies and has led many researchers to advocate ANNs as an attractive, non-linear alternative to traditional statistical methods. The goal of this study is to design a Baltic cod recruitment model (FishANN that can account for complex ecosystem interactions. To this end, we (1 build a quantitative model representation of the conceptual understanding of the complex ecosystem interactions driving Baltic cod recruitment dynamics, and (2 apply the model to strengthen the current capability to project future changes in Baltic cod recruitment. FishANN is demonstrated to bring multiple stressors together into one model framework and estimate the relative importance of these stressors while interpreting the complex nonlinear interactions between them. Additional requirements to further improve the current study in the future are also proposed.

  19. Mammalian aPKC/Par polarity complex mediated regulation of epithelial division orientation and cell fate

    Energy Technology Data Exchange (ETDEWEB)

    Vorhagen, Susanne; Niessen, Carien M., E-mail: carien.niessen@uni-koeln.de

    2014-11-01

    Oriented cell division is a key regulator of tissue architecture and crucial for morphogenesis and homeostasis. Balanced regulation of proliferation and differentiation is an essential property of tissues not only to drive morphogenesis but also to maintain and restore homeostasis. In many tissues orientation of cell division is coupled to the regulation of differentiation producing daughters with similar (symmetric cell division, SCD) or differential fate (asymmetric cell division, ACD). This allows the organism to generate cell lineage diversity from a small pool of stem and progenitor cells. Division orientation and/or the ratio of ACD/SCD need to be tightly controlled. Loss of orientation or an altered ratio can promote overgrowth, alter tissue architecture and induce aberrant differentiation, and have been linked to morphogenetic diseases, cancer and aging. A key requirement for oriented division is the presence of a polarity axis, which can be established through cell intrinsic and/or extrinsic signals. Polarity proteins translate such internal and external cues to drive polarization. In this review we will focus on the role of the polarity complex aPKC/Par3/Par6 in the regulation of division orientation and cell fate in different mammalian epithelia. We will compare the conserved function of this complex in mitotic spindle orientation and distribution of cell fate determinants and highlight common and differential mechanisms in which this complex is used by tissues to adapt division orientation and cell fate to the specific properties of the epithelium.

  20. Organoarsenicals in poultry litter: detection, fate, and toxicity.

    Science.gov (United States)

    P Mangalgiri, Kiranmayi; Adak, Asok; Blaney, Lee

    2015-02-01

    Arsenic contamination in groundwater has endangered the health and safety of millions of people around the world. One less studied mechanism for arsenic introduction into the environment is the use of organoarsenicals in animal feed. Four organoarsenicals are commonly employed as feed additives: arsanilic acid, carbarsone, nitarsone, and roxarsone. Organoarsenicals are composed of a phenylarsonic acid molecule with substituted functional groups. This review documents the use of organoarsenicals in the poultry industry, reports analytical methods available for quantifying organic arsenic, discusses the fate and transport of organoarsenicals in environmental systems, and identifies toxicological concerns associated with these chemicals. In reviewing the literature on organoarsenicals, several research needs were highlighted: advanced analytical instrumentation that allows for identification and quantification of organoarsenical degradation products; a greater research emphasis on arsanilic acid, carbarsone, and nitarsone; identification of degradation pathways, products, and kinetics; and testing/development of agricultural wastewater and solid treatment technologies for organoarsenical-laden waste. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Production, use, and fate of all plastics ever made.

    Science.gov (United States)

    Geyer, Roland; Jambeck, Jenna R; Law, Kara Lavender

    2017-07-01

    Plastics have outgrown most man-made materials and have long been under environmental scrutiny. However, robust global information, particularly about their end-of-life fate, is lacking. By identifying and synthesizing dispersed data on production, use, and end-of-life management of polymer resins, synthetic fibers, and additives, we present the first global analysis of all mass-produced plastics ever manufactured. We estimate that 8300 million metric tons (Mt) as of virgin plastics have been produced to date. As of 2015, approximately 6300 Mt of plastic waste had been generated, around 9% of which had been recycled, 12% was incinerated, and 79% was accumulated in landfills or the natural environment. If current production and waste management trends continue, roughly 12,000 Mt of plastic waste will be in landfills or in the natural environment by 2050.

  2. Fate of alkali and trace metals in biomass gasification

    International Nuclear Information System (INIS)

    Salo, K.; Mojtahedi, W.

    1998-01-01

    The fate of alkali metals (Na, K) and eleven toxic trace elements (Hg, Cd, Be, Se, Sb, As, Pb, Zn, Cr, Co, Ni) in biomass gasification have been extensively investigated in Finland in the past ten years. The former due to the gas turbine requirements and the latter to comply with environmental regulations. In this paper the results of several experimental studies to measure Na and K in the vapor phase after the gas cooler of a simplified (air-blown) Integrated Gasification Combined-Cycle (IGCC) system are reported. Also, trace element emissions from an IGCC plant using alfalfa as the feedstock are discussed and the concentration of a few toxic trace metals in the vapor phase in the gasifier product gas are reported. (author)

  3. Spatially patterned matrix elasticity directs stem cell fate

    Science.gov (United States)

    Yang, Chun; DelRio, Frank W.; Ma, Hao; Killaars, Anouk R.; Basta, Lena P.; Kyburz, Kyle A.; Anseth, Kristi S.

    2016-08-01

    There is a growing appreciation for the functional role of matrix mechanics in regulating stem cell self-renewal and differentiation processes. However, it is largely unknown how subcellular, spatial mechanical variations in the local extracellular environment mediate intracellular signal transduction and direct cell fate. Here, the effect of spatial distribution, magnitude, and organization of subcellular matrix mechanical properties on human mesenchymal stem cell (hMSCs) function was investigated. Exploiting a photodegradation reaction, a hydrogel cell culture substrate was fabricated with regions of spatially varied and distinct mechanical properties, which were subsequently mapped and quantified by atomic force microscopy (AFM). The variations in the underlying matrix mechanics were found to regulate cellular adhesion and transcriptional events. Highly spread, elongated morphologies and higher Yes-associated protein (YAP) activation were observed in hMSCs seeded on hydrogels with higher concentrations of stiff regions in a dose-dependent manner. However, when the spatial organization of the mechanically stiff regions was altered from a regular to randomized pattern, lower levels of YAP activation with smaller and more rounded cell morphologies were induced in hMSCs. We infer from these results that irregular, disorganized variations in matrix mechanics, compared with regular patterns, appear to disrupt actin organization, and lead to different cell fates; this was verified by observations of lower alkaline phosphatase (ALP) activity and higher expression of CD105, a stem cell marker, in hMSCs in random versus regular patterns of mechanical properties. Collectively, this material platform has allowed innovative experiments to elucidate a novel spatial mechanical dosing mechanism that correlates to both the magnitude and organization of spatial stiffness.

  4. Surface and virulence properties of environmental Vibrio cholerae non-O1 from Albufera Lake (Valencia, Spain).

    Science.gov (United States)

    Amaro, C; Toranzo, A E; González, E A; Blanco, J; Pujalte, M J; Aznar, R; Garay, E

    1990-04-01

    A total of 140 environmental Vibrio cholerae non-O1 isolates, together with several culture collection strains from both environmental and clinical sources, were studied in relation to hemagglutination, surface hydrophobicity, and the enzymatic, hemolytic, cytotoxic, and enterotoxic activities of their extracellular products. A total of 78 and 62% of the strains produced hemagglutinins and exohemagglutinins, respectively. Four different hemagglutinating and two exohemagglutinating activities were found by using eight sugars in the inhibition assays. Cell-bound mannose-sensitive hemagglutination was detected mainly in chicken blood, whereas fucose-sensitive hemagglutination was recorded only in human blood. Cell-bound hemagglutinin resistant to all sugars tested was the only one related to surface hydrophobicity. The surface properties varied along the growth curves. The non-O1 strains displayed strong enzymatic and hemolytic activities, except for esculin hydrolysis. Of 26 non-O1 isolates selected for cytotoxin and enterotoxin production, 23 showed a wide spectrum of cytotoxic effects on cell lines of poikilothermic and homoiothermic species, but they were weakly enterotoxigenic in the infant mouse test. All extracellular products of cytotoxic strains were proteolytic, lipolytic, and hemolytic, and a high percentage produced hemagglutination of chicken blood. The cytotoxic factors in the non-O1 strains analyzed were not R plasmid mediated.

  5. Indicator Properties of Baltic Zooplankton for Classification of Environmental Status within Marine Strategy Framework Directive.

    Science.gov (United States)

    Gorokhova, Elena; Lehtiniemi, Maiju; Postel, Lutz; Rubene, Gunta; Amid, Callis; Lesutiene, Jurate; Uusitalo, Laura; Strake, Solvita; Demereckiene, Natalja

    2016-01-01

    The European Marine Strategy Framework Directive requires the EU Member States to estimate the level of anthropogenic impacts on their marine systems using 11 Descriptors. Assessing food web response to altered habitats is addressed by Descriptor 4 and its indicators, which are being developed for regional seas. However, the development of simple foodweb indicators able to assess the health of ecologically diverse, spatially variable and complex interactions is challenging. Zooplankton is a key element in marine foodwebs and thus comprise an important part of overall ecosystem health. Here, we review work on zooplankton indicator development using long-term data sets across the Baltic Sea and report the main findings. A suite of zooplankton community metrics were evaluated as putative ecological indicators that track community state in relation to Good Environmental Status (GES) criteria with regard to eutrophication and fish feeding conditions in the Baltic Sea. On the basis of an operational definition of GES, we propose mean body mass of zooplankton in the community in combination with zooplankton stock measured as either abundance or biomass to be applicable as an integrated indicator that could be used within the Descriptor 4 in the Baltic Sea. These metrics performed best in predicting zooplankton being in-GES when considering all datasets evaluated. However, some other metrics, such as copepod biomass, the contribution of copepods to the total zooplankton biomass or biomass-based Cladocera: Copepoda ratio, were equally reliable or even superior in certain basin-specific assessments. Our evaluation suggests that in several basins of the Baltic Sea, zooplankton communities currently appear to be out-of-GES, being comprised by smaller zooplankters and having lower total abundance or biomass compared to the communities during the reference conditions; however, the changes in the taxonomic structure underlying these trends vary widely across the sea basins due to

  6. On diel variability of marine sediment backscattering properties caused by microphytobenthos photosynthesis: Impact of environmental factors

    Science.gov (United States)

    Gorska, Natalia; Kowalska-Duda, Ewa; Pniewski, Filip; Latała, Adam

    2018-06-01

    The study has been motivated by the development of the hydroacoustic techniques for mapping and classifying the benthic habitats and for the research of the microbenthos photosynthesis in the semi-enclosed Baltic Sea, particularly sensitive to human activity. The investigation of the effect of the benthic microalgal photosynthesis on the echo signal from the Baltic sandy sediments is continuing. The study clarifies the impact of the abiotic and biotic factors on the diel variation of the backscattering caused by the benthic microalgal photosynthetic activity. Five multiday laboratory experiments, different in hydrophysical or biological conditions, were conducted. During each measurement series, the "day" (illumination) and "night" (darkness) conditions (L:D cycle) were simulated and the diel variations of the echo energy of the backscattered signal were analyzed. The hydroacoustic data were acquired along with measuring biological and biooptical parameters and oxygen concentration. The study demonstrated the impact of microphytobenthos photosynthesis on the backscattering properties of the marine sediment which is sensitive to the illumination level, benthic microalgal biomass and macrozoobenthos bioturbation.

  7. Investigation of the influence of physical and chemical properties of biodiesel in the fuel economy, energy and environmental performance of motor diesel

    Directory of Open Access Journals (Sweden)

    Korpach А.

    2016-08-01

    Full Text Available Due to exhaustion of world energy reserves and significant environmental pollution by harmful substances, current research aimed at determining the effectiveness of alternative fuels. In the article compare two samples of biodiesel and studied their physical and chemical properties accordance with International Standard. Effect of different samples of biodiesel in fuel economy, energy and environmental performance automotive diesel determined by the bench tests of 4CH11,0/12.5 (D-241 diesel. The difference between physical and chemical properties of two biodiesel samples influenced to the fuel efficiency and environmental performance of the diesel. Operation on biodiesel with higher density and kinematic viscosity provide increases of maximum power and torque and increase fuel consumption. It also increases the concentration of nitrogen oxides in exhaust gases and it opacity. The results allow evaluate how the deviation of physical and chemical properties of biodiesel could affect the operational performance of the engine.

  8. Effects of engineered nano-titanium dioxide on pore surface properties and phosphorus adsorption of sediment: its environmental implications.

    Science.gov (United States)

    Luo, Zhuanxi; Wang, Zhenhong; Wei, Qunshan; Yan, Changzhou; Liu, Feng

    2011-09-15

    Understanding the environmental safety and human health implications of engineered nanoparticles (ENPs) is of worldwide importance. As an important ENPs, engineered nano-TiO(2) (Enano-TiO(2)) may have been substantially deposited in aquatic sediments because of its widely uses. Sediment pore surface properties would be thus significantly influenced due to the large surface area of Enano-TiO(2). In this study, Enano-TiO(2) was found to greatly impact on sediment pore surface properties. The attachment of Enano-TiO(2) particles to sediment surfaces enhanced markedly BET specific surface area and t-Plot external specific surface area, and thereby increased sediment phosphorus (P) adsorption maximum (S(max)). Contrarily, the fill of Enano-TiO(2) particles into the micropores of sediments could significantly reduce t-Plot micropore specific surface area, and cause slight decrease in sediment P binding energy (K). Clearly, P sorbed in sediment would be easily released because of the decreasing P binding energy of the sediment with elevated Enano-TiO(2). Enano-TiO(2) would thus cause aggravated endogenous pollution in water if such sediment was re-suspended on disturbance. The results obtained in this study contribute to our increasing knowledge of how to regulate physicochemical behavior of pollutants in sediments under the influences of Enano-TiO(2) and/or similar ENPs. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. O DIREITO DE PROPRIEDADE LIMITADO À DIMENSÃO AMBIENTAL / THE PROPERTY RIGHT LIMITED TO ENVIRONMENTAL CONCERNS

    Directory of Open Access Journals (Sweden)

    Hildemar Meneguzzi de Carvalho

    2015-12-01

    Full Text Available The current article has the objective of discussing the limitations imposed on property rights. Using the qualitative research methodology and inductive method, the construction of the text comes from the study of the limiting factors of the use, enjoyment and fruition of the premises, using the contents of the Brazilian Federal Constitution and some of the reflections promoted by Antonio Bartolini, in the lecture Le situazioni giuridiche soggettive nel diritto europeo, as the main theoretical foundation. This research is justified because of the current planet pollution and the scarcity of several natural resources. It attempts to analyze the principle of social function as a restrictive factor, added to the natural and legal - internal and external - limits; modeled on the example of the condominium, the urban plan, the division of urban land and the expropriation, giving particular emphasis to environmental restrictions. As a result, we seek to certify the feasibility of absolute and arbitrary use of the property for a society that moves towards sustainability.

  10. Fate and transport processes controlling the migration of hazardous and radioactive materials from the Area 5 Radioactive Waste Management Site (RWMS)

    International Nuclear Information System (INIS)

    Estrella, R.

    1994-10-01

    Desert vadose zones have been considered as suitable environments for the safe and long-term isolation of hazardous wastes. Low precipitation, high evapotranspiration and thick unsaturated alluvial deposits commonly found in deserts make them attractive as waste disposal sites. The fate and transport of any contaminant in the subsurface is ultimately determined by the operating retention and transformation processes in the system and the end result of the interactions among them. Retention (sorption) and transformation are the two major processes that affect the amount of a contaminant present and available for transport. Retention processes do not affect the total amount of a contaminant in the soil system, but rather decrease or eliminate the amount available for transport at a given point in time. Sorption reactions retard the contaminant migration. Permanent binding of solute by the sorbent is also possible. These processes and their interactions are controlled by the nature of the hazardous waste, the properties of the porous media and the geochemical and environmental conditions (temperature, moisture and vegetation). The present study summarizes the available data and investigates the fate and transport processes that govern the migration of contaminants from the Radioactive Waste Management Site (RWMS) in Area 5 of the Nevada Test Site (NTS). While the site is currently used only for low-level radioactive waste disposal, past practices have included burial of material now considered hazardous. Fundamentals of chemical and biological transformation processes are discussed subsequently, followed by a discussion of relevant results

  11. Fate and transport processes controlling the migration of hazardous and radioactive materials from the Area 5 Radioactive Waste Management Site (RWMS)

    Energy Technology Data Exchange (ETDEWEB)

    Estrella, R.

    1994-10-01

    Desert vadose zones have been considered as suitable environments for the safe and long-term isolation of hazardous wastes. Low precipitation, high evapotranspiration and thick unsaturated alluvial deposits commonly found in deserts make them attractive as waste disposal sites. The fate and transport of any contaminant in the subsurface is ultimately determined by the operating retention and transformation processes in the system and the end result of the interactions among them. Retention (sorption) and transformation are the two major processes that affect the amount of a contaminant present and available for transport. Retention processes do not affect the total amount of a contaminant in the soil system, but rather decrease or eliminate the amount available for transport at a given point in time. Sorption reactions retard the contaminant migration. Permanent binding of solute by the sorbent is also possible. These processes and their interactions are controlled by the nature of the hazardous waste, the properties of the porous media and the geochemical and environmental conditions (temperature, moisture and vegetation). The present study summarizes the available data and investigates the fate and transport processes that govern the migration of contaminants from the Radioactive Waste Management Site (RWMS) in Area 5 of the Nevada Test Site (NTS). While the site is currently used only for low-level radioactive waste disposal, past practices have included burial of material now considered hazardous. Fundamentals of chemical and biological transformation processes are discussed subsequently, followed by a discussion of relevant results.

  12. Properties of sediment-algae flocs as function of shear and environmental conditions : a laboratory study

    Science.gov (United States)

    Deng, Z.; He, Q.; Chassagne, C.; Manning, A. J.

    2017-12-01

    It has been observed that flocculation in-situ is greatly influenced by biochemical parameters[De Lucas Pardo, 2014]. In our previous work [Deng, 2017], we have found that flocs observed in the Yangtze Estuary are composed of mixtures of sediment and algae. In particular we have shown that flocs can be composed solely of algae aggregates. Depending on their position in the water column, the composition of flocs changes, as more or less sediment can be part of the floc. The presence of algae (phytoplankton biomass) in a floc is linked to the measured chlorophyll α concentration [Uncles et al., 1998]. The Particle Size Distribution (PSD) found in-situ depends on parameters such as position in the water column and shear rate, and also seasons. We showed that the PSD found in-situ is similar to the one measured in the lab, for the same floc composition and environmental conditions. In the present work we extend the laboratory investigations by analysing the impact of the floc history on its PSD. The PSD can be bimodal after a grow-break-up-regrow phase, indicating that flocs growth process depend on a timescale that is larger than the timescale associated to the change in shear rate. We will discuss the behaviour of the parameters needed in the flocculation model we propose upon the relevant variables. The ultimate goal is to propose a model that can be implemented in large scale sediment transport models. ReferencesDe Lucas Pardo, M. (2014), Effect of biota on fine sediment transport processes: A study of Lake Markermeer, TU Delft, Delft University of Technology. Deng, Z. (2017), Algae effects on cohesive sediment flocculation: a case study based on field observation in Yangtze Estuary, China (submitted)Uncles, R., A. Easton, M. Griffiths, C. Harris, R. Howland, I. Joint, R. King, A. Morris, and D. Plummer (1998), Concentrations of suspended chlorophyll in the tidal Yorkshire Ouse and Humber Estuary, Science of The Total Environment, 210-211, 367-375, doi:10.1016/s

  13. Milk yield, quality, and coagulation properties of 6 breeds of goats: Environmental and individual variability.

    Science.gov (United States)

    Vacca, Giuseppe M; Stocco, Giorgia; Dettori, Maria L; Pira, Emanuela; Bittante, Giovanni; Pazzola, Michele

    2018-05-09

    Goat milk and cheese production is continuously increasing and milk composition and coagulation properties (MCP) are useful tools to predict cheesemaking aptitude. The present study was planned to investigate the extension of lactodynamographic analysis up to 60 min in goat milk, to measure the farm and individual factors, and to investigate differences among 6 goat breeds. Daily milk yield (dMY) was recorded and milk samples collected from 1,272 goats reared in 35 farms. Goats were of 6 different breeds: Saanen and Camosciata delle Alpi for the Alpine type, and Murciano-Granadina, Maltese, Sarda, and Sarda Primitiva for the Mediterranean type. Milk composition (fat, protein, lactose, pH; somatic cell score; logarithmic bacterial count) and MCP [rennet coagulation time (RCT, min), curd-firming time (k 20 , min), curd firmness at 30, 45, and 60 min after rennet addition (a 30 , a 45 , and a 60 , mm)] were recorded, and daily fat and protein yield (dFPY g/d) was calculated as the sum of fat and protein concentration multiplied by the dMY. Data were analyzed using different statistical models to measure the effects of farm, parity, stage of lactation and breed; lastly, the direct and the indirect effect of breed were quantified by comparing the variance of breed from models with or without the inclusion of linear regression of fat, protein, lactose, pH, bacterial, somatic cell counts, and dMY. Orthogonal contrasts were performed to compare least squares means. Almost all traits exhibited high variability, with coefficients of variation between 32 (for RCT) and 63% (for a 30 ). The proportion of variance regarding dMY, dFPY, and milk composition due to the farm was moderate, whereas for MCP it was low, except for a 60 , at 69%. Parity affected both yield and quality traits of milk, with least squares means of dMY and dFPY showing an increase and RCT and curd firmness traits a decrease from the first to the last parity class. All milk quality traits, excluding fat, were

  14. Observation of optical properties and sources of aerosols at Buddha's birthplace, Lumbini, Nepal: environmental implications.

    Science.gov (United States)

    Rupakheti, Dipesh; Kang, Shichang; Rupakheti, Maheswar; Cong, Zhiyuan; Tripathee, Lekhendra; Panday, Arnico K; Holben, Brent N

    2018-03-15

    For the first time, aerosol optical properties are measured over Lumbini, Nepal, with CIMEL sunphotometer of the Aerosol Robotic Network (AERONET) program. Lumbini is a sacred place as the birthplace of Lord Buddha, and thus a UNESCO world heritage site, located near the northern edge of the central Indo-Gangetic Plains (IGP) and before the Himalayan foothills (and Himalayas) to its north. Average aerosol optical depth (AOD) is found to be 0.64 ± 0.38 (0.06-3.28) over the sampling period (January 2013-December 2014), with the highest seasonal AOD during the post-monsoon season (0.72 ± 0.44). More than 80% of the daily averaged AOD values, during the monitoring period, are above 0.3, indicating polluted conditions in the region. The levels of aerosol load observed over Lumbini are comparable to those observed at several heavily polluted sites in the IGP. Based on the relationship between AOD and Ångstrom exponent (α), anthropogenic, biomass burning, and mixed aerosols are found to be the most prevalent aerosol types. The aerosol volume-size distribution is bi-modal during all four seasons with modes centered at 0.1-0.3 and 3-4 μm. For both fine and coarse modes, the highest volumetric concentration of ~ 0.08 μm -3  μm -2 is observed during the post-monsoon and pre-monsoon seasons. As revealed by the single-scattering albedo (SSA), asymmetry parameter (AP), and refractive index (RI) analyses, aerosol loading over Lumbini is dominated by absorbing, urban-industrial, and biomass burning aerosols.

  15. Intramolecular didehydro-Diels-Alder reaction and its impact on the structure-function properties of environmentally sensitive fluorophores.

    Science.gov (United States)

    Brummond, Kay M; Kocsis, Laura S

    2015-08-18

    Reaction discovery plays a vital role in accessing new chemical entities and materials possessing important function.1 In this Account, we delineate our reaction discovery program regarding the [4 + 2] cycloaddition reaction of styrene-ynes. In particular, we highlight our studies that lead to the realization of the diverging reaction mechanisms of the intramolecular didehydro-Diels-Alder (IMDDA) reaction to afford dihydronaphthalene and naphthalene products. Formation of the former involves an intermolecular hydrogen atom abstraction and isomerization, whereas the latter is formed via an unexpected elimination of H2. Forming aromatic compounds by a unimolecular elimination of H2 offers an environmentally benign alternative to typical oxidation protocols. We also include in this Account ongoing work focused on expanding the scope of this reaction, mainly its application to the preparation of cyclopenta[b]naphthalenes. Finally, we showcase the synthetic utility of the IMDDA reaction by preparing novel environmentally sensitive fluorophores. The choice to follow this path was largely influenced by the impact this reaction could have on our understanding of the structure-function relationships of these molecular sensors by taking advantage of a de novo construction and functionalization of the aromatic portion of these compounds. We were also inspired by the fact that, despite the advances that have been made in the construction of small molecule fluorophores, access to rationally designed fluorescent probes or sensors possessing varied and tuned photophysical, spectral, and chemical properties are still needed. To this end, we report our studies to correlate fluorophore structure with photophysical property relationships for a series of solvatochromic PRODAN analogs and viscosity-sensitive cyanoacrylate analogs. The versatility of this de novo strategy for fluorophore synthesis was demonstrated by showing that a number of functional groups could be installed at

  16. Apical versus Basal Neurogenesis Directs Cortical Interneuron Subclass Fate

    Directory of Open Access Journals (Sweden)

    Timothy J. Petros

    2015-11-01

    Full Text Available Fate determination in the mammalian telencephalon, with its diversity of neuronal subtypes and relevance to neuropsychiatric disease, remains a critical area of study in neuroscience. Most studies investigating this topic focus on the diversity of neural progenitors within spatial and temporal domains along the lateral ventricles. Often overlooked is whether the location of neurogenesis within a fate-restricted domain is associated with, or instructive for, distinct neuronal fates. Here, we use in vivo fate mapping and the manipulation of neurogenic location to demonstrate that apical versus basal neurogenesis influences the fate determination of major subgroups of cortical interneurons derived from the subcortical telencephalon. Somatostatin-expressing interneurons arise mainly from apical divisions along the ventricular surface, whereas parvalbumin-expressing interneurons originate predominantly from basal divisions in the subventricular zone. As manipulations that shift neurogenic location alter interneuron subclass fate, these results add an additional dimension to the spatial-temporal determinants of neuronal fate determination.

  17. THE FATE OF TRACE METALS IN A ROTARY KILN INCINERATOR WITH A VENTURI/PACKED COLUMN SCRUBBER - VOLUME II: APPENDICES

    Science.gov (United States)

    A 5-week series of pilot-scale incineration tests, employing a synthetic waste feed, was performed at the U.S. Environmental Protection Agency's Incineration Research Facility to evaluate the fate of trace metals fed to a rotary kiln incinerator equipped with a venturi scrubber/p...

  18. Fate of Zinc Oxide Nanoparticles during Anaerobic Digestion of Wastewater and Post-Treatment Processing of Sewage Sludge

    Energy Technology Data Exchange (ETDEWEB)

    Lombi, Enzo; Donner, Erica; Tavakkoli, Ehsan; Turney, Terence W.; Naidu, Ravi; Miller, Bradley W.; Scheckel, Kirk G. (U. South Australia); (EPA); (Monash)

    2013-01-14

    The rapid development and commercialization of nanomaterials will inevitably result in the release of nanoparticles (NPs) to the environment. As NPs often exhibit physical and chemical properties significantly different from those of their molecular or macrosize analogs, concern has been growing regarding their fate and toxicity in environmental compartments. The wastewater-sewage sludge pathway has been identified as a key release pathway leading to environmental exposure to NPs. In this study, we investigated the chemical transformation of two ZnO-NPs and one hydrophobic ZnO-NP commercial formulation (used in personal care products), during anaerobic digestion of wastewater. Changes in Zn speciation as a result of postprocessing of the sewage sludge, mimicking composting/stockpiling, were also assessed. The results indicated that 'native' Zn and Zn added either as a soluble salt or as NPs was rapidly converted to sulfides in all treatments. The hydrophobicity of the commercial formulation retarded the conversion of ZnO-NP. However, at the end of the anaerobic digestion process and after postprocessing of the sewage sludge (which caused a significant change in Zn speciation), the speciation of Zn was similar across all treatments. This indicates that, at least for the material tested, the risk assessment of ZnO-NP through this exposure pathway can rely on the significant knowledge already available in regard to other 'conventional' forms of Zn present in sewage sludge.

  19. Tire wear particles in the aquatic environment - A review on generation, analysis, occurrence, fate and effects.

    Science.gov (United States)

    Wagner, Stephan; Hüffer, Thorsten; Klöckner, Philipp; Wehrhahn, Maren; Hofmann, Thilo; Reemtsma, Thorsten

    2018-08-01

    Tire wear particles (TWP), generated from tire material during use on roads have gained increasing attention as part of organic particulate contaminants, such as microplastic, in aquatic environments. The available information on properties and generation of TWP, analytical techniques to determine TWP, emissions, occurrence and behavior and ecotoxicological effects of TWP are reviewed with a focus on surface water as a potential receptor. TWP emissions are traffic related and contribute 5-30% to non-exhaust emissions from traffic. The mass of TWP generated is estimated at 1,327,000 t/a for the European Union, 1,120,000 t/a for the United States and 133,000 t/a for Germany. For Germany, this is equivalent to four times the amount of pesticides used. The mass of TWP ultimately entering the aquatic environment strongly depends on the extent of collection and treatment of road runoff, which is highly variable. For the German highways it is estimated that up to 11,000 t/a of TWP reach surface waters. Data on TWP concentrations in the environment, including surface waters are fragmentary, which is also due to the lack of suitable analytical methods for their determination. Information on TWP properties such as density and size distribution are missing; this hampers assessing the fate of TWP in the aquatic environment. Effects in the aquatic environment may stem from TWP itself or from compounds released from TWP. It is concluded that reliable knowledge on transport mechanism to surface waters, concentrations in surface waters and sediments, effects of aging, environmental half-lives of TWP as well as effects on aquatic organisms are missing. These aspects need to be addressed to allow for the assessment of risk of TWP in an aquatic environment. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Fate of Chloromethanes in the Atmospheric Environment: Implications for Human Health, Ozone Formation and Depletion, and Global Warming Impacts.

    Science.gov (United States)

    Tsai, Wen-Tien

    2017-09-21

    Among the halogenated hydrocarbons, chloromethanes (i.e., methyl chloride, CH₃Cl; methylene chloride, CH₂Cl₂; chloroform, CHCl₃; and carbon tetrachloride, CCl₄) play a vital role due to their extensive uses as solvents and chemical intermediates. This article aims to review their main chemical/physical properties and commercial/industrial uses, as well as the environment and health hazards posed by them and their toxic decomposition products. The environmental properties (including atmospheric lifetime, radiative efficiency, ozone depletion potential, global warming potential, photochemical ozone creation potential, and surface mixing ratio) of these chlorinated methanes are also reviewed. In addition, this paper further discusses their atmospheric fates and human health implications because they are apt to reside in the lower atmosphere when released into the environment. According to the atmospheric degradation mechanism, their toxic degradation products in the troposphere include hydrogen chloride (HCl), carbon monoxide (CO), chlorine (Cl₂), formyl chloride (HCOCl), carbonyl chloride (COCl₂), and hydrogen peroxide (H₂O₂). Among them, COCl₂ (also called phosgene) is a powerful irritating gas, which is easily hydrolyzed or thermally decomposed to form hydrogen chloride.

  1. Fate of Chloromethanes in the Atmospheric Environment: Implications for Human Health, Ozone Formation and Depletion, and Global Warming Impacts

    Science.gov (United States)

    Tsai, Wen-Tien

    2017-01-01

    Among the halogenated hydrocarbons, chloromethanes (i.e., methyl chloride, CH3Cl; methylene chloride, CH2Cl2; chloroform, CHCl3; and carbon tetrachloride, CCl4) play a vital role due to their extensive uses as solvents and chemical intermediates. This article aims to review their main chemical/physical properties and commercial/industrial uses, as well as the environment and health hazards posed by them and their toxic decomposition products. The environmental properties (including atmospheric lifetime, radiative efficiency, ozone depletion potential, global warming potential, photochemical ozone creation potential, and surface mixing ratio) of these chlorinated methanes are also reviewed. In addition, this paper further discusses their atmospheric fates and human health implications because they are apt to reside in the lower atmosphere when released into the environment. According to the atmospheric degradation mechanism, their toxic degradation products in the troposphere include hydrogen chloride (HCl), carbon monoxide (CO), chlorine (Cl2), formyl chloride (HCOCl), carbonyl chloride (COCl2), and hydrogen peroxide (H2O2). Among them, COCl2 (also called phosgene) is a powerful irritating gas, which is easily hydrolyzed or thermally decomposed to form hydrogen chloride. PMID:29051455

  2. Assessing the dependence of bulk ice properties from probes with anti-shatter tips on environmental conditions

    Science.gov (United States)

    Jackson, Robert C.

    Ice clouds have significant impacts on the Earth's radiative budget. Their radiative impact highly depends on ice cloud microphysical properties. Climate and weather prediction models have to make certain assumptions about how the various processes are represented. Observations of how cloud properties vary with environmental conditions can help evaluate some parameterizations used in models. However, sufficient data are not available to characterize how ice crystal properties vary as a function of environmental conditions. Furthermore, many of these assumptions are derived from historical datasets collected by in situ probes, namely optical array probes that can be contaminated by shattered artifacts generated by large particles shattering on the probe tips and inlets. Therefore this study has two main objectives. Prior estimates of ice crystal size distributions derived from 2D Cloud Probes (2DCs) have been artificially amplified by small ice crystals generated from the shattering of large ice crystals on the probe tips. Although anti-shatter tips and algorithms exist, there is considerable uncertainty in their effectiveness. Therefore, this thesis first examines the differences in ice crystal size distributions, and bulk and optical properties from adjacent 2DCs with standard and anti-shatter tips, and processed with and without anti-shattering algorithms. The measurements were obtained from the National Research Council of Canada Convair-580 during the 2008 Indirect and Semi-Direct Aerosol Campaign (ISDAC) and the National Center for Atmospheric Research C-130 during the 2011 Instrumentation Development and Education in Airborne Science 2011 (IDEAS-2011). The 2DC size distributions are compared with those from the Holographic Detector for Clouds (HOLODEC), which has anti-shatter tips and allows for identification of shattering through spatial statistics. The ratio of the number concentration N of particles with maximum dimensions 125 to 500 mum from the 2DC with

  3. Fate of Gases generated from Nuclear Wastes

    Energy Technology Data Exchange (ETDEWEB)

    Srinivasulu, M.; Francis, A. J. [Pohang Univ. of Science and Technology, Pohang (Korea, Republic of); Francis, A. J. [Brookhaven National Laboratory, New York (United States)

    2013-05-15

    The backfill materials such as cement, bentonite or crushed rock are used as engineered barriers against groundwater infiltration and radionuclide transport. Gas generation from radioactive wastes is attributed to radiolysis, corrosion of metals, and degradation of organic materials. Corrosion of steel drums and biodegradation of organic materials in L/ILW can generate gas which causes pressure build up and has the potential to compromise the integrity of waste containers and release the radionuclides and other contaminants into the environment. Performance assessment therefore requires a detailed understanding of the source and fate of gas generation and transport within the disposal system. Here we review the sources and fate of various type of gases generated from nuclear wastes and repositories. Studies on modeling of the fate and transport of repository gases primarily deal with hydrogen and CO{sub 2}. Although hydrogen and carbon dioxide are the major gases of concern, microbial transformations of these gases in the subterranean environments could be significant. Metabolism of hydrogen along with the carbon dioxide results in the formation of methane, low molecular weight organic compounds and cell biomass and thus could affect the total inventory in a repository environment. Modeling studies should take into consideration of both the gas generation and consumption processes over the long-term.

  4. Redox Regulation of Endothelial Cell Fate

    Science.gov (United States)

    Song, Ping; Zou, Ming-Hui

    2014-01-01

    Endothelial cells (ECs) are present throughout blood vessels and have variable roles in both physiological and pathological settings. EC fate is altered and regulated by several key factors in physiological or pathological conditions. Reactive nitrogen species and reactive oxygen species derived from NAD(P)H oxidases, mitochondria, or nitric oxide-producing enzymes are not only cytotoxic but also compose a signaling network in the redox system. The formation, actions, key molecular interactions, and physiological and pathological relevance of redox signals in ECs remain unclear. We review the identities, sources, and biological actions of oxidants and reductants produced during EC function or dysfunction. Further, we discuss how ECs shape key redox sensors and examine the biological functions, transcriptional responses, and post-translational modifications evoked by the redox system in ECs. We summarize recent findings regarding the mechanisms by which redox signals regulate the fate of ECs and address the outcome of altered EC fate in health and disease. Future studies will examine if the redox biology of ECs can be targeted in pathophysiological conditions. PMID:24633153

  5. Effects of engineered nano-titanium dioxide on pore surface properties and phosphorus adsorption of sediment: Its environmental implications

    International Nuclear Information System (INIS)

    Luo, Zhuanxi; Wang, Zhenhong; Wei, QunShan; Yan, Changzhou; Liu, Feng

    2011-01-01

    Highlights: → The attachment of Enano-TiO 2 to surface enhanced markedly sediment BET surface area and t-Plot external surface area. → The fill of Enano-TiO 2 into the micropores reduced significantly the sediment t-Plot micropore surface area. → Enano-TiO 2 could increase sediment phosphorus (P) adsorption maximum and decrease in sediment P binding energy. → P would be easily released because of the decreasing P binding energy of the sediment with elevated Enano-TiO 2 . - Abstract: Understanding the environmental safety and human health implications of engineered nanoparticles (ENPs) is of worldwide importance. As an important ENPs, engineered nano-TiO 2 (Enano-TiO 2 ) may have been substantially deposited in aquatic sediments because of its widely uses. Sediment pore surface properties would be thus significantly influenced due to the large surface area of Enano-TiO 2 . In this study, Enano-TiO 2 was found to greatly impact on sediment pore surface properties. The attachment of Enano-TiO 2 particles to sediment surfaces enhanced markedly BET specific surface area and t-Plot external specific surface area, and thereby increased sediment phosphorus (P) adsorption maximum (S max ). Contrarily, the fill of Enano-TiO 2 particles into the micropores of sediments could significantly reduce t-Plot micropore specific surface area, and cause slight decrease in sediment P binding energy (K). Clearly, P sorbed in sediment would be easily released because of the decreasing P binding energy of the sediment with elevated Enano-TiO 2 . Enano-TiO 2 would thus cause aggravated endogenous pollution in water if such sediment was re-suspended on disturbance. The results obtained in this study contribute to our increasing knowledge of how to regulate physicochemical behavior of pollutants in sediments under the influences of Enano-TiO 2 and/or similar ENPs.

  6. Property Evaluation and Damage Evolution of Environmental Barrier Coatings and Environmental Barrier Coated SiC/SiC Ceramic Matrix Composite Sub-Elements

    Science.gov (United States)

    Zhu, Dongming; Halbig, Michael; Jaskowiak, Martha; Hurst, Janet; Bhatt, Ram; Fox, Dennis S.

    2014-01-01

    This paper describes recent development of environmental barrier coatings on SiC/SiC ceramic matrix composites. The creep and fatigue behavior at aggressive long-term high temperature conditions have been evaluated and highlighted. Thermal conductivity and high thermal gradient cyclic durability of environmental barrier coatings have been evaluated. The damage accumulation and complex stress-strain behavior environmental barrier coatings on SiCSiC ceramic matrix composite turbine airfoil subelements during the thermal cyclic and fatigue testing of have been also reported.

  7. The sources and fate of radionuclides emitted to the atmosphere

    International Nuclear Information System (INIS)

    Sandalls, J.

    2001-01-01

    The thesis represents an account of the sources and fate of radionuclides entering the atmosphere, and indicates where the candidate, through his own work, has contributed to the overall picture. The sources of the natural and man-made radionuclides found in the atmosphere are identified. New data on emissions from UK coal-fired power stations and UK steel works are reported. Radionuclides produced in nuclear fission and released to the atmosphere in the detonation of nuclear weapons, in nuclear accidents, and through routine discharges from nuclear sites have added to the atmospheric burden of radioactive materials; both acute and chronic low-level emissions are discussed. The various natural processes which remove radionuclides from the atmosphere are described. Soon after release, many radioactive materials become attached to the atmospheric aerosol, but others undergo gas-phase reactions. Some gases are sufficiently long-lived in the troposphere as to find their way into the stratosphere where their fate may be determined by the short-wave radiation from the sun. The nature of the particles of fuel emitted to the atmosphere in the explosion and fire at the Chernobyl nuclear power plant in 1986 are discussed, together with the associated environmental problems. The ground is the major sink for radionuclides leaving the atmosphere, and the behaviour of the more radiologically important radionuclides following deposition is described with special reference to: (i) fallout in both the urban and living environments; (ii) the pathways which may lead to contamination of the food chain; (iii) how the fuel particle fallout from Chernobyl was unique in nuclear accidents; (iv) soil-to-plant transfer of radioelements and (v) how radiation exposure of man can be mitigated in both the contaminated urban and rural environments. (author)

  8. Geochemical Fate and Transport of Sildenafil and Vardenafil

    Science.gov (United States)

    Richter, L.; Boudinot, G.; Vulava, V. M.; Cory, W. C.

    2015-12-01

    The geochemical fate of pharmaceuticals and their degradation products is a developing environmental field. The geologic, chemical, and biological fate of these pollutants has become very relevant with the increase in human population and the resulting increase in pollutant concentrations in the environment. In this study, we focus on sildenafil (SDF) and vardenafil (VDF), active compounds in Viagra and Levitra, respectively, two commonly used erectile dysfunction drugs. The main objective is to determine the sorption potential and transport behavior of these two compounds in natural soils. Both SDF and VDF are complex organic molecules with multiple amine functional groups in their structures. Two types of natural acidic soils (pH≈4.5), an organic-rich soil (7.6% OM) and clay-rich soil (5.1% clay) were used in this study to determine which soil components influence sorption behavior of both compounds. Sorption isotherms measured using batch reactors were nearly linear, but sorption was stronger in soil that contained higher clay content. Both compounds have multiple pKas due to the amine functional groups, the relevant pKas of SDF are 5.97 and 7.27, and those of VDF's are 4.72 and 6.21. These values indicate that these compounds likely behave as cations in soil suspensions and hence were strongly sorbed to negatively-charged clay minerals present in both soils. The clay composition in both soils is predominantly kaolinite with smaller amount of montmorillonite, both of which have a predominantly negative surface charge. Transport experiments using glass chromatography columns indicated that both compounds were more strongly retarded in the clay-rich soils. Breakthrough curves from the transport experiments were modeled using convection-dispersion transport equations. The organic matter in the soil seemed to play a less dominant role in the geochemistry in this study, but is likely to transform both compounds into derivative compounds as seen in other studies.

  9. Occurrence, fate and transformation of emerging contaminants in water: An overarching review of the field.

    Science.gov (United States)

    Wilkinson, John; Hooda, Peter S; Barker, James; Barton, Stephen; Swinden, Julian

    2017-12-01

    Many of the products and drugs used commonly contain chemical components which may persist through sewage treatment works (STW) and eventually enter the aquatic environment as parent compounds, metabolites, or transformation products. Pharmaceuticals and personal care products (PPCPs) and other emerging contaminants (ECs) have been detected in waters (typically ng/L) as well as more recently bound to sediment and plastic particles (typically ng/g). Despite significant advancement of knowledge since the late 1990s, the fate of these contaminants/transformation products once introduced into the aquatic environment remains relatively unresolved. This review provides a unique focus on the fate of seven major groups of PPCPs/ECs in the aquatic environment, which is frequently not found in similar works which are often compound or topic-specific and limited in background knowledge. Key findings include: a) some replacements for regulation precluded/banned chemicals may be similarly persistent in the environment as those they replace, b) the adsorption of potentially bioactive chemicals to micro- and nanoplastics is a significant topic with risks to aquatic organisms potentially greater than previously thought, and c) micro-/nanoplastics are likely to remain of significant concern for centuries after regulatory limitations on their use become active due to the slow degradation of macro-plastics into smaller components. An interdisciplinary perspective on recent advances in the field is presented here in a unique way which highlights both the principle science and direction of research needed to elucidate the fate and transport patterns of aquatic PPCPs/ECs. Unlike similar reviews, which are often topic-specific, here we aim to present an overarching review of the field with focus on the occurrence, transformation and fate of emerging contaminants. Environmental presence of seven major classes of contaminants (analygesics, antibiotics, antineoplastics, beta

  10. Environmental dynamic, business strategy, and financial performance: An empirical study of Indonesian property and real estate industry

    Directory of Open Access Journals (Sweden)

    Imam Wahyudi

    2013-05-01

    Full Text Available Firm’s strategic orientation involves synchronizing environmental dynamics, corporate strategy and capital structure in order to achieve firm performance targets. The co-alignment model used successfully in the hospitality industry might be used in a wider context as a framework in explaining these relationships simultaneously. Using the data of public firms in Indonesia during the period of 1996-2010, we found that co-alignment model can be implemented in property and real estate industry as well as in hospitality industry. Normal 0 false false false IN X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

  11. Making fate and exposure models for freshwater ecotoxicity in life cycle assessment suitable for organic acids and bases.

    Science.gov (United States)

    van Zelm, Rosalie; Stam, Gea; Huijbregts, Mark A J; van de Meent, Dik

    2013-01-01

    Freshwater fate and exposure factors were determined for organic acids and bases, making use of the knowledge on electrical interaction of ionizing chemicals and their sorption to particles. The fate factor represents the residence time in the environment whereas exposure factors equal the dissolved fraction of a chemical. Multimedia fate, exposure, and effect model USES-LCA was updated to take into account the influence of ionization, based upon the acid dissociation constant (pK(a)) of a chemical, and the environmental pH. Freshwater fate (FF) and exposure (XF) factors were determined for 415 acids and 496 bases emitted to freshwater, air, and soil. The relevance of taking account of the degree of ionization of chemicals was tested by determining the ratio (R) of the new vs. fate and exposure factors determined with USES-LCA suitable for neutral chemicals only. Our results show that the majority of freshwater fate and exposure factors of chemicals that are largely ionized in the environment are larger with the ionics model compared to the factors determined with the neutrals model version. R(FF) ranged from 2.4×10(-1) to 1.6×10(1) for freshwater emissions, from 1.2×10(-2) to 2.0×10(4) for soil emissions and from 5.8×10(-2) to 6.0×10(3) for air emissions, and R(XF) from 5.3×10(-1) to 2.2×10(1). Prediction of changed solid-water partitioning, implying a change in runoff and in removal via sedimentation, and prediction of negligible air-water partition coefficient, leading to negligible volatilization were the main contributors to the changes in freshwater fate factors. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Using integrated environmental modeling to automate a process-based Quantitative Microbial Risk Assessment

    Science.gov (United States)

    Integrated Environmental Modeling (IEM) organizes multidisciplinary knowledge that explains and predicts environmental-system response to stressors. A Quantitative Microbial Risk Assessment (QMRA) is an approach integrating a range of disparate data (fate/transport, exposure, an...

  13. Using Integrated Environmental Modeling to Automate a Process-Based Quantitative Microbial Risk Assessment (presentation)

    Science.gov (United States)

    Integrated Environmental Modeling (IEM) organizes multidisciplinary knowledge that explains and predicts environmental-system response to stressors. A Quantitative Microbial Risk Assessment (QMRA) is an approach integrating a range of disparate data (fate/transport, exposure, and...

  14. Synthetic RNA Controllers for Programming Mammalian Cell Fate and Function

    Science.gov (United States)

    2015-11-04

    Final report for “Synthetic RNA controllers for programming mammalian cell fate and function” Principal Investigator: Christina D. Smolke...SUBTITLE Synthetic RNA controllers for programming mammalian cell fate and function 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER...Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18   2 Synthetic RNA controllers for programming mammalian cell fate and function Task 1

  15. Property.

    Science.gov (United States)

    Piele, Philip K.

    Numerous cases in this year's chapter dealt with the same topics of previous years--contracts and bids for building construction, and detachment and annexation of a portion of a school district. The courts continued to attribute board discretionary authority to school boards in school property matters. Intergovernmental disputes over ownership or…

  16. Uranium fate in wetland mesocosms: Effects of plants at two ...

    Science.gov (United States)

    Small-scale continuous flow wetland mesocosms (~0.8 L) were used to evaluate how plant roots under different iron loadings affect uranium (U) mobility. When significant concentrations of ferrous iron (Fe) were present at circumneutral pH values, U concentrations in root exposed sediments were an order of magnitude greater than concentrations in root excluded sediments. Micro X-ray absorption near-edge structure (µ-XANES) spectroscopy indicated that U was associated with the plant roots primarily as U(VI) or U(V), with limited evidence of U(IV). Micro X-ray fluorescence (µ-XRF) of plant roots suggested that for high iron loading at circumneutral pH, U was co-located with Fe, perhaps co-precipitated with root Fe plaques, while for low iron loading at a pH of ~4 the correlation between U and Fe was not significant, consistent with previous observations of U associated with organic matter. Quantitative PCR analyses indicated that the root exposed sediments also contained elevated numbers of Geobacter spp., which are likely associated with enhanced iron cycling, but may also reduce mobile U(VI) to less mobile U(IV) species. There are significant uncertainties regarding the environmental fate of uranium (U) and efforts to minimize U exposures require understanding of its mobility in environmental systems. Much research has focused on sequestering U as solids within groundwater aquifers, where localized risks can be controlled.1 Subsurface sequestration limits t

  17. Computational properties of mitochondria in T cell activation and fate.

    Science.gov (United States)

    Uzhachenko, Roman; Shanker, Anil; Dupont, Geneviève

    2016-11-01

    In this article, we review how mitochondrial Ca 2+ transport (mitochondrial Ca 2+ uptake and Na + /Ca 2+ exchange) is involved in T cell biology, including activation and differentiation through shaping cellular Ca 2+ signals. Based on recent observations, we propose that the Ca 2+ crosstalk between mitochondria, endoplasmic reticulum and cytoplasm may form a proportional-integral-derivative (PID) controller. This PID mechanism (which is well known in engineering) could be responsible for computing cellular decisions. In addition, we point out the importance of analogue and digital signal processing in T cell life and implication of mitochondrial Ca 2+ transport in this process. © 2016 The Authors.

  18. Evaluation of terrestrial microcosms for detection, fate, and survival analysis of genetically engineered microorganisms and their recombinant genetic material

    Energy Technology Data Exchange (ETDEWEB)

    Fredrickson, J.K.; Seidler, R.J.

    1989-02-01

    The research included in this document represents the current scientific information available regarding the applicability of terrestrial microcosms and related methodologies for evaluating detection methods and the fate and survival of microorganisms in the environment. The three terrestrial microcosms described in this document were used to evaluate the survival and fate of recombinant bacteria in soils and in association with plant surfaces and insects and their transport through soil with percolating water and root systems, and to test new methods and procedures to improve detection and enumeration of bacteria in soil. Simple (potting soil composed of peat mix and perlite, lacking environmental control and monitoring) and complex microcosms (agricultural soil with partial control and monitoring of environmental conditions) were demonstrated to be useful tools for preliminary assessments of microbial viability in terrestrial ecosystems. These studies evaluated the survival patterns of Enterobacter cloacae (pBR322) in soil and on plant surfaces and the ingestion of this same microorganism by cutworms and survival in the foregut and frass. The Versacore microcosm design was used to monitor the fate and competitiveness of genetically engineered bacteria in soil. Both selective media and gene probes were used successfully to follow the fate of two recombinant Pseudomonas sp. introduced into Versacore microcosms. Intact soil-core microcosms were employed to evaluate the fate and transport of genetically altered Azospirillum sp. and Pseudomonas sp. in soil and the plant rhizosphere. The usefulness of these various microcosms as a tool for risk assessment is underscored by the ease in obtaining soil from a proposed field release site to evaluate subsequent GEM fate and survival.

  19. Rotenone formulation fate in Lake Davis following the 2007 treatment.

    Science.gov (United States)

    Vasquez, Martice E; Rinderneck, Janna; Newman, Julie; McMillin, Stella; Finlayson, Brian; Mekebri, Abdou; Crane, David; Tjeerdema, Ronald S

    2012-05-01

    In September 2007, Lake Davis (near Portola, California) was treated by the California Department of Fish and Game with CFT Legumine, a rotenone formulation, to eradicate the invasive northern pike (Esox lucius). The objective of this report is to describe the fate of the five major formulation constituents-rotenone, rotenolone, methyl pyrrolidone (MP), diethylene glycol monethyl ether (DEGEE), and Fennedefo 99-in water, sediment, and brown bullhead catfish (Ameiurus nebulosus; a rotenone-resistant species) by determination of their half-lives (t(1/2)) and pseudo first-order dissipation rate constants (k). The respective t(1/2) values in water for rotenone, rotenolone, MP, DEGEE, and Fennedefo 99 were 5.6, 11.1, 4.6, 7.7, and 13.5 d; in sediments they were 31.1, 31.8, 10.0, not able to calculate, and 48.5 d; and in tissues were 6.1, 12.7, 3.7, 3.2, and 10.4 d, respectively. Components possessing low water solubility values (rotenone and rotenolone) persisted longer in sediments (not detectable after 157 d) and tissues (<212 d) compared with water, whereas the water-miscible components (MP and DEGEE) dissipated more quickly from all matrices, except for Fennedefo 99, which was the most persistent in water (83 d). None of the constituents was found to bioaccumulate in tissues as a result of treatment. In essence, the physicochemical properties of the chemical constituents effectively dictated their fate in the lake following treatment. Copyright © 2012 SETAC.

  20. Organic contaminant transport and fate in the subsurface: evolution of knowledge and understanding

    Science.gov (United States)

    Essaid, Hedeff I.; Bekins, Barbara A.; Cozzarelli, Isabelle M.

    2015-01-01

    Toxic organic contaminants may enter the subsurface as slightly soluble and volatile nonaqueous phase liquids (NAPLs) or as dissolved solutes resulting in contaminant plumes emanating from the source zone. A large body of research published in Water Resources Research has been devoted to characterizing and understanding processes controlling the transport and fate of these organic contaminants and the effectiveness of natural attenuation, bioremediation, and other remedial technologies. These contributions include studies of NAPL flow, entrapment, and interphase mass transfer that have advanced from the analysis of simple systems with uniform properties and equilibrium contaminant phase partitioning to complex systems with pore-scale and macroscale heterogeneity and rate-limited interphase mass transfer. Understanding of the fate of dissolved organic plumes has advanced from when biodegradation was thought to require oxygen to recognition of the importance of anaerobic biodegradation, multiple redox zones, microbial enzyme kinetics, and mixing of organic contaminants and electron acceptors at plume fringes. Challenges remain in understanding the impacts of physical, chemical, biological, and hydrogeological heterogeneity, pore-scale interactions, and mixing on the fate of organic contaminants. Further effort is needed to successfully incorporate these processes into field-scale predictions of transport and fate. Regulations have greatly reduced the frequency of new point-source contamination problems; however, remediation at many legacy plumes remains challenging. A number of fields of current relevance are benefiting from research advances from point-source contaminant research. These include geologic carbon sequestration, nonpoint-source contamination, aquifer storage and recovery, the fate of contaminants from oil and gas development, and enhanced bioremediation.

  1. Occurrence, fate and transformation of emerging contaminants in water: An overarching review of the field

    International Nuclear Information System (INIS)

    Wilkinson, John; Hooda, Peter S.; Barker, James; Barton, Stephen; Swinden, Julian

    2017-01-01

    Many of the products and drugs used commonly contain chemical components which may persist through sewage treatment works (STW) and eventually enter the aquatic environment as parent compounds, metabolites, or transformation products. Pharmaceuticals and personal care products (PPCPs) and other emerging contaminants (ECs) have been detected in waters (typically ng/L) as well as more recently bound to sediment and plastic particles (typically ng/g). Despite significant advancement of knowledge since the late 1990s, the fate of these contaminants/transformation products once introduced into the aquatic environment remains relatively unresolved. This review provides a unique focus on the fate of seven major groups of PPCPs/ECs in the aquatic environment, which is frequently not found in similar works which are often compound or topic-specific and limited in background knowledge. Key findings include: a) some replacements for regulation precluded/banned chemicals may be similarly persistent in the environment as those they replace, b) the adsorption of potentially bioactive chemicals to micro- and nanoplastics is a significant topic with risks to aquatic organisms potentially greater than previously thought, and c) micro-/nanoplastics are likely to remain of significant concern for centuries after regulatory limitations on their use become active due to the slow degradation of macro-plastics into smaller components. An interdisciplinary perspective on recent advances in the field is presented here in a unique way which highlights both the principle science and direction of research needed to elucidate the fate and transport patterns of aquatic PPCPs/ECs. Unlike similar reviews, which are often topic-specific, here we aim to present an overarching review of the field with focus on the occurrence, transformation and fate of emerging contaminants. Environmental presence of seven major classes of contaminants (analygesics, antibiotics, antineoplastics, beta

  2. The Yin and Yang of chromatin dynamics in adult stem cell fate selection

    Science.gov (United States)

    Adam, Rene C.; Fuchs, Elaine

    2015-01-01

    Adult organisms rely on tissue stem cells for maintenance and repair. During homeostasis, the concerted action of local niche signals and epigenetic regulators establish stable gene expression patterns to ensure that stem cells are not lost over time. However, stem cells also provide host tissues with a remarkable plasticity to respond to perturbations. How adult stem cells choose and acquire new fates is unknown, but the genome-wide mapping of epigenetic landscapes suggests a critical role for chromatin remodeling in these processes. Here, we explore the emerging role of chromatin modifiers and pioneer transcription factors in adult stem cell fate decisions and plasticity, which ensure that selective lineage choices are only made when environmentally cued. PMID:26689127

  3. Environmental Chemistry Methods (ECM) Index - 0-9

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with a number as the first character.

  4. Effects of engineered nano-titanium dioxide on pore surface properties and phosphorus adsorption of sediment: Its environmental implications

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Zhuanxi [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Wang, Zhenhong [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Zhangzhou Normal University, Department of Chemistry and Environment Sciences, Zhangzhou 363000 (China); Wei, QunShan [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Yan, Changzhou, E-mail: czyan@iue.ac.cn [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Liu, Feng [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China)

    2011-09-15

    Highlights: {yields} The attachment of Enano-TiO{sub 2} to surface enhanced markedly sediment BET surface area and t-Plot external surface area. {yields} The fill of Enano-TiO{sub 2} into the micropores reduced significantly the sediment t-Plot micropore surface area. {yields} Enano-TiO{sub 2} could increase sediment phosphorus (P) adsorption maximum and decrease in sediment P binding energy. {yields} P would be easily released because of the decreasing P binding energy of the sediment with elevated Enano-TiO{sub 2}. - Abstract: Understanding the environmental safety and human health implications of engineered nanoparticles (ENPs) is of worldwide importance. As an important ENPs, engineered nano-TiO{sub 2} (Enano-TiO{sub 2}) may have been substantially deposited in aquatic sediments because of its widely uses. Sediment pore surface properties would be thus significantly influenced due to the large surface area of Enano-TiO{sub 2}. In this study, Enano-TiO{sub 2} was found to greatly impact on sediment pore surface properties. The attachment of Enano-TiO{sub 2} particles to sediment surfaces enhanced markedly BET specific surface area and t-Plot external specific surface area, and thereby increased sediment phosphorus (P) adsorption maximum (S{sub max}). Contrarily, the fill of Enano-TiO{sub 2} particles into the micropores of sediments could significantly reduce t-Plot micropore specific surface area, and cause slight decrease in sediment P binding energy (K). Clearly, P sorbed in sediment would be easily released because of the decreasing P binding energy of the sediment with elevated Enano-TiO{sub 2}. Enano-TiO{sub 2} would thus cause aggravated endogenous pollution in water if such sediment was re-suspended on disturbance. The results obtained in this study contribute to our increasing knowledge of how to regulate physicochemical behavior of pollutants in sediments under the influences of Enano-TiO{sub 2} and/or similar ENPs.

  5. Iron Oxide Minerals in Atmospheric Dust and Source Sediments-Studies of Types and Properties to Assess Environmental Effects

    Science.gov (United States)

    Reynolds, R. L.; Goldstein, H. L.; Moskowitz, B. M.; Till, J. L.; Flagg, C.; Kokaly, R. F.; Munson, S.; Landry, C.; Lawrence, C. R.; Hiza, M. M.; D'Odorico, P.; Painter, T. H.

    2011-12-01

    Ferric oxide minerals in atmospheric dust can influence atmospheric temperatures, accelerate melting of snow and ice, stimulate marine phytoplankton productivity, and impact human health. Such effects vary depending on iron mineral type, size, surface area, and solubility. Generally, the presence of ferric oxides in dust is seen in the red, orange, or yellow hues of plumes that originate in North Africa, central and southwest Asia, South America, western North America, and Australia. Despite their global importance, these minerals in source sediments, atmospheric dust, and downwind aeolian deposits remain poorly described with respect to specific mineralogy, particle size and surface area, or presence in far-traveled aerosol compounds. The types and properties of iron minerals in atmospheric dust can be better understood using techniques of rock magnetism (measurements at 5-300 K), Mössbauer and high-resolution visible and near-infrared reflectance spectroscopy; chemical reactivity of iron oxide phases; and electron microscopy for observing directly the ferric oxide coatings and particles. These studies can elucidate the diverse environmental effects of iron oxides in dust and can help to identify dust-source areas. Dust-source sediments from the North American Great Basin and Colorado Plateau deserts and the Kalahari Desert, southern Africa, were used to compare average reflectance values with a magnetic parameter (hard isothermal remanent magnetization, HIRM) for ferric oxide abundance. Lower reflectance values correspond strongly with higher HIRM values, indicating that ferric oxides (hematite or goethite, or both) contribute to absorption of solar radiation in these sediments. Dust deposited to snow cover of the San Juan Mountains (Colorado) and Wasatch Mountains (Utah) was used to characterize dust composition compared with properties of sediments exposed in source-areas identified from satellite retrievals. Results from multiple methods indicate that

  6. Cell fate regulation in the shoot meristem.

    Science.gov (United States)

    Laux, T; Mayer, K F

    1998-04-01

    The shoot meristem is a proliferative centre containing pluripotent stem cells that are the ultimate source of all cells and organs continuously added to the growing shoot. The progeny of the stem cells have two developmental options, either to renew the stem cell population or to leave the meristem and to differentiate, possibly according to signals from more mature tissue. The destiny of each cell depends on its position within the dynamic shoot meristem. Genetic data suggest a simple model in which graded positional information is provided by antagonistic gene functions and is interpreted by genes which regulate cell fate.

  7. Fate of leptophos residues in milk products

    International Nuclear Information System (INIS)

    Zayed, S.M.A.D.; Mohammed, S.I.

    1981-01-01

    The fate of leptophos residues in various milk products was studied using 14 C-phenyl labelled leptophos. Milk products were prepared from milk fortified with the radioactive insecticide by methods simulating those used in industry. The highest leptophos level was found in butter and the lowest in skim milk and whey. Analysis of the radioactive residues in all products showed the presence of leptophos alone. A trace of the oxon could be detected in whey. The results obtained in this investigation indicated that processing of milk did not affect the nature of leptophos to any appreciable extent. (author)

  8. Fate of nitrogenous fertilizers in forest soil

    International Nuclear Information System (INIS)

    Pang, P.C.K.

    1984-01-01

    The fate of the nitrogenous fertilizers through the processes of denitrification, ammonia volatilization, immobilization and uptake by a conifer is determined, with the aid of 15 N-labelled fertizers. The foliage of Douglas-fir was able to absorb gaseous ammonia under optimal conditions. Denitrification and immobilization of fertilizer-N by forest soil were highest with forest floor samples and decreased with depth. Laboratory studies with four-year-old Douglas-fir demostrated that a higher quantity of fertilizer-N was utilized by trees when the nitrogen was supplied as NO 3 - rather than NH 4 + . (M.A.C.) [pt

  9. Watch Out for the “Living Dead”: Cell-Free Enzymes and Their Fate

    Directory of Open Access Journals (Sweden)

    Federico Baltar

    2018-01-01

    Full Text Available Microbes are the engines driving biogeochemical cycles. Microbial extracellular enzymatic activities (EEAs are the “gatekeepers” of the carbon cycle. The total EEA is the sum of cell-bound (i.e., cell-attached, and dissolved (i.e., cell-free enzyme activities. Cell-free enzymes make up a substantial proportion (up to 100% of the total marine EEA. Although we are learning more about how microbial diversity and function (including total EEA will be affected by environmental changes, little is known about what factors control the importance of the abundant cell-free enzymes. Since cell-attached EEAs are linked to the cell, their fate will likely be linked to the factors controlling the cell’s fate. In contrast, cell-free enzymes belong to a kind of “living dead” realm because they are not attached to a living cell but still are able to perform their function away from the cell; and as such, the factors controlling their activity and fate might differ from those affecting cell-attached enzymes. This article aims to place cell-free EEA into the wider context of hydrolysis of organic matter, deal with recent studies assessing what controls the production, activity and lifetime of cell-free EEA, and what their fate might be in response to environmental stressors. This perspective article advocates the need to go “beyond the living things,” studying the response of cells/organisms to different stressors, but also to study cell-free enzymes, in order to fully constrain the future and evolution of marine biogeochemical cycles.

  10. Watch Out for the “Living Dead”: Cell-Free Enzymes and Their Fate

    Science.gov (United States)

    Baltar, Federico

    2018-01-01

    Microbes are the engines driving biogeochemical cycles. Microbial extracellular enzymatic activities (EEAs) are the “gatekeepers” of the carbon cycle. The total EEA is the sum of cell-bound (i.e., cell-attached), and dissolved (i.e., cell-free) enzyme activities. Cell-free enzymes make up a substantial proportion (up to 100%) of the total marine EEA. Although we are learning more about how microbial diversity and function (including total EEA) will be affected by environmental changes, little is known about what factors control the importance of the abundant cell-free enzymes. Since cell-attached EEAs are linked to the cell, their fate will likely be linked to the factors controlling the cell’s fate. In contrast, cell-free enzymes belong to a kind of “living dead” realm because they are not attached to a living cell but still are able to perform their function away from the cell; and as such, the factors controlling their activity and fate might differ from those affecting cell-attached enzymes. This article aims to place cell-free EEA into the wider context of hydrolysis of organic matter, deal with recent studies assessing what controls the production, activity and lifetime of cell-free EEA, and what their fate might be in response to environmental stressors. This perspective article advocates the need to go “beyond the living things,” studying the response of cells/organisms to different stressors, but also to study cell-free enzymes, in order to fully constrain the future and evolution of marine biogeochemical cycles. PMID:29354095

  11. The influence of vertical sorbed phase transport on the fate of organic chemicals in surface soils.

    Science.gov (United States)

    McLachlan, Michael S; Czub, Gertje; Wania, Frank

    2002-11-15

    Gaseous exchange between surface soil and the atmosphere is an important process in the environmental fate of many chemicals. It was hypothesized that this process is influenced by vertical transport of chemicals sorbed to soil particles. Vertical sorbed phase transport in surface soils occurs by many processes such as bioturbation, cryoturbation, and erosion into cracks formed by soil drying. The solution of the advection/diffusion equation proposed by Jury et al. to describe organic chemical fate in a uniformly contaminated surface soil was modified to include vertical sorbed phase transport This process was modeled using a sorbed phase diffusion coefficient, the value of which was derived from soil carbon mass balances in the literature. The effective diffusivity of the chemical in a typical soil was greater in the modified model than in the model without sorbed phase transport for compounds with log K(OW) > 2 and log K(OA) > 6. Within this chemical partitioning space, the rate of volatilization from the surface soil was larger in the modified model than in the original model by up to a factor of 65. The volatilization rate was insensitive to the value of the sorbed phase diffusion coefficient throughout much of this chemical partitioning space, indicating that the surface soil layer was essentially well-mixed and that the mass transfer coefficient was determined by diffusion through the atmospheric boundary layer only. When this process was included in a non-steady-state regional multimedia chemical fate model running with a generic emissions scenario to air, the predicted soil concentrations increased by upto a factor of 25,whilethe air concentrations decreased by as much as a factor of approximately 3. Vertical sorbed phase transport in the soil thus has a major impact on predicted air and soil concentrations, the state of equilibrium, and the direction and magnitude of the chemical flux between air and soil. It is a key process influencing the environmental

  12. Environmental Safety of the Use of Major Surfactant Classes in North America

    Science.gov (United States)

    Cowan-Ellsberry, Christina; Belanger, Scott; Dorn, Philip; Dyer, Scott; McAvoy, Drew; Sanderson, Hans; Versteeg, Donald; Ferrer, Darci

    2014-01-01

    This paper brings together over 250 published and unpublished studies on the environmental properties, fate, and toxicity of the four major, high-volume surfactant classes and relevant feedstocks. The surfactants and feedstocks covered include alcohol sulfate or alcohol sulfate (AS), alcohol ethoxysulfate (AES), linear alkylbenzene sulfonate (LAS), alcohol ethoxylate (AE), and long-chain alcohol (LCOH). These chemicals are used in a wide range of personal care and cleaning products. To date, this is the most comprehensive report on these substance's chemical structures, use, and volume information, physical/chemical properties, environmental fate properties such as biodegradation and sorption, monitoring studies through sewers, wastewater treatment plants and eventual release to the environment, aquatic and sediment toxicity, and bioaccumulation information. These data are used to illustrate the process for conducting both prospective and retrospective risk assessments for large-volume chemicals and categories of chemicals with wide dispersive use. Prospective risk assessments of AS, AES, AE, LAS, and LCOH demonstrate that these substances, although used in very high volume and widely released to the aquatic environment, have no adverse impact on the aquatic or sediment environments at current levels of use. The retrospective risk assessments of these same substances have clearly demonstrated that the conclusions of the prospective risk assessments are valid and confirm that these substances do not pose a risk to the aquatic or sediment environments. This paper also highlights the many years of research that the surfactant and cleaning products industry has supported, as part of their environmental sustainability commitment, to improve environmental tools, approaches, and develop innovative methods appropriate to address environmental properties of personal care and cleaning product chemicals, many of which have become approved international standard methods. PMID

  13. Modelling the impact of climate change on the atmospheric transport and the fate of persistent organic pollutants in the Arctic

    Science.gov (United States)

    Hansen, K. M.; Christensen, J. H.; Geels, C.; Silver, J. D.; Brandt, J.

    2015-06-01

    The Danish Eulerian Hemispheric Model (DEHM) was applied to investigate how projected climate changes will affect the atmospheric transport of 13 persistent organic pollutants (POPs) to the Arctic and their environmental fate within the Arctic. Three sets of simulations were performed, one with present day emissions and initial environmental concentrations from a 20-year spin-up simulation, one with present day emissions and with initial environmental concentrations set to zero and one without emissions but with initial environmental concentrations from the 20-year spin-up simulation. Each set of simulations consisted of two 10-year time slices representing the present (1990-2000) and future (2090-2100) climate conditions. DEHM was driven using meteorological input from the global circulation model, ECHAM/MPI-OM, simulating the SRES (Special Report on Emissions Scenarios) A1B climate scenario. Under the applied climate and emission scenarios, the total mass of all compounds was predicted to be up to 55 % lower across the Northern Hemisphere at the end of the 2090s than in the 1990s. The mass of HCHs within the Arctic was predicted to be up to 38 % higher, whereas the change in mass of the PCBs was predicted to range from 38 % lower to 17 % higher depending on the congener and the applied initial environmental concentrations. The results of this study also indicate that contaminants with no or a short emission history will be more rapidly transported to and build up in the arctic environment in a future warmer climate. The process that dominates the environmental behaviour of POPs in the Arctic under a future warmer climate scenario is the shift in mass of POPs from the surface media to the atmosphere induced by the higher mean temperature. This is to some degree counteracted by higher degradation rates also following the higher mean temperature. The more dominant of these two processes depends on the physical-chemical properties of the compounds. Previous model

  14. Presence, fate and effects of the intense sweetener sucralose in the aquatic environment

    Energy Technology Data Exchange (ETDEWEB)

    Tollefsen, Knut Erik, E-mail: ket@niva.no [Norwegian Institute for Water Research (NIVA), Gaustadalleen 21, N-0349 Oslo (Norway); Nizzetto, Luca [Norwegian Institute for Water Research (NIVA), Gaustadalleen 21, N-0349 Oslo (Norway); Huggett, Duane B. [Department of Biological Sciences, University of North Texas, P.O. Box 310559, Denton, TX 76203 (United States)

    2012-11-01

    Sucralose (1,6-dichloro-1,6-dideoxy-b-D-fructo-furanosyl 4-chloro-4-deoxy-a-D-galactopyranoside), sold under the trade name Splenda Registered-Sign , has been detected in municipal effluents and surface waters in the United States and Europe. The environmental presence of sucralose has led to interest in the possibility of toxic effects in non-target species. This review presents an environmental risk assessment of sucralose based on available data concerning its presence, fate and effects in the environment. Sucralose, which is made by selective chlorination of sucrose, is a highly stable compound, which undergoes negligible metabolism in mammals, including humans, and displays a low biodegradation potential in the environment. This intense sweetener is highly soluble in water, displays a low bioaccumulation potential and a low sorption potential to soil and organic matter, and thus is predominantly present in the water column. The predicted environmental concentration (PEC) for sucralose, based on measured data in surface waters, was determined to be 10 {mu}g/L. Aquatic toxicity studies using standardized, validated protocols used in regulatory decision making indicate that sucralose does not alter survival, growth and reproduction of aquatic organisms (such as plants, algae, crustaceans and fish) at concentrations > 9000 times higher than those detected in the environment. Some studies, using non-standardized protocols, have reported behavioral and other non-traditional responses in aquatic organisms, but the relevance of these findings for assessing adverse effects on individuals and populations will require further investigation. In terms of traditional risk assessment, the proposed predicted no effect concentration for aquatic organisms (PNEC) was determined to be 0.93 mg/L, based on the lowest no effect concentration (NOEC) from a validated chronic study with mysid shrimp and an application factor of 100. The resultant PEC/PNEC quotient was determined to be

  15. Presence, fate and effects of the intense sweetener sucralose in the aquatic environment

    International Nuclear Information System (INIS)

    Tollefsen, Knut Erik; Nizzetto, Luca; Huggett, Duane B.

    2012-01-01

    Sucralose (1,6-dichloro-1,6-dideoxy-b-D-fructo-furanosyl 4-chloro-4-deoxy-a-D-galactopyranoside), sold under the trade name Splenda®, has been detected in municipal effluents and surface waters in the United States and Europe. The environmental presence of sucralose has led to interest in the possibility of toxic effects in non-target species. This review presents an environmental risk assessment of sucralose based on available data concerning its presence, fate and effects in the environment. Sucralose, which is made by selective chlorination of sucrose, is a highly stable compound, which undergoes negligible metabolism in mammals, including humans, and displays a low biodegradation potential in the environment. This intense sweetener is highly soluble in water, displays a low bioaccumulation potential and a low sorption potential to soil and organic matter, and thus is predominantly present in the water column. The predicted environmental concentration (PEC) for sucralose, based on measured data in surface waters, was determined to be 10 μg/L. Aquatic toxicity studies using standardized, validated protocols used in regulatory decision making indicate that sucralose does not alter survival, growth and reproduction of aquatic organisms (such as plants, algae, crustaceans and fish) at concentrations > 9000 times higher than those detected in the environment. Some studies, using non-standardized protocols, have reported behavioral and other non-traditional responses in aquatic organisms, but the relevance of these findings for assessing adverse effects on individuals and populations will require further investigation. In terms of traditional risk assessment, the proposed predicted no effect concentration for aquatic organisms (PNEC) was determined to be 0.93 mg/L, based on the lowest no effect concentration (NOEC) from a validated chronic study with mysid shrimp and an application factor of 100. The resultant PEC/PNEC quotient was determined to be well below 1 (PEC

  16. Evaluation of terrestrial microcosms for assessing the fate and effects of genetically engineered microorganisms on ecological processes

    Energy Technology Data Exchange (ETDEWEB)

    Fredrickson, J.K.; Bentjen, S.A.; Bolton, H. Jr.; Li, S.W.; Ligotke, M.W.; McFadden, K.M.; Van Voris, P.

    1989-04-01

    This project evaluates and modifies the existing US Environmental Protection Agency's Office of Pesticides and Toxic Substances (EPA/OPTS) terrestrial microcosm test system and test protocols such that they can be used to determine the environmental fate and ecological hazards of genetically engineered microorganisms (GEMs). The intact soil-core microcosm represents terrestrial ecosystems, and when coupled with appropriate test protocols, such microcosms may be appropriate to define and limit risks associated with the intentional release of GEMs. The terrestrial microcosm test system was used to investigate the survival and transport of two model GEMs (Azospirillum lipoferum and Pseudomonas sp. Tn5 mutants) to various trophic levels and niches and through intact soil cores. Subsequent effects on nutrient cycling and displacement of indigenous microorganisms were evaluated. The model organisms were a diazotrophic root-colonizing bacterium (A. lipoferum) and a wheat root growth-inhibiting rhizobacterium (Pseudomonas sp.). The transposable element Tn5 was used as a genetic marker for both microorganisms in two separate experiments. The organisms were subjected to transposon mutagenesis using a broad host-range-mobilizable suicide plasmid. The transposon Tn5 conferred levels of kanamycin resistance up to 500 ..mu..g/ml (Pseudomonas sp.), which allowed for selection of the bacteria from environmental samples. The presence of Tn5 DNA in the genome of the model GEMs also allowed the use of Tn5 gene probes to confirm and enumerate the microorganisms in different samples from the microcosms. Two types of root growth-inhibiting Pseudomonas sp. Tn5 mutants were obtained and used in microcosm studies: those that lacked the ability to inhibit either wheat root growth or the growth of other microorganisms in vitro (tox/sup /minus//) and those which retained these properties (tox/sup +/). 53 refs., 7 figs., 6 tabs.

  17. Biokinetics of zinc oxide nanoparticles: toxicokinetics, biological fates, and protein interaction

    Directory of Open Access Journals (Sweden)

    Choi SJ

    2014-12-01

    Full Text Available Soo-Jin Choi,1 Jin-Ho Choy2 1Department of Food Science and Technology, Seoul Women's University, 2Center for Intelligent Nano Bio Materials (CINBM, Department of Bioinspired Science and Department of Chemistry and Nanoscience, Ewha Womans University, Seoul, South Korea Abstract: Biokinetic studies of zinc oxide (ZnO nanoparticles involve systematic and quantitative analyses of absorption, distribution, metabolism, and excretion in plasma and tissues of whole animals after exposure. A full understanding of the biokinetics provides basic information about nanoparticle entry into systemic circulation, target organs of accumulation and toxicity, and elimination time, which is important for predicting the long-term toxic potential of nanoparticles. Biokinetic behaviors can be dependent on physicochemical properties, dissolution property in biological fluids, and nanoparticle–protein interaction. Moreover, the determination of biological fates of ZnO nanoparticles in the systemic circulation and tissues is critical in interpreting biokinetic behaviors and predicting toxicity potential as well as mechanism. This review focuses on physicochemical factors affecting the biokinetics of ZnO nanoparticles, in concert with understanding bioavailable fates and their interaction with proteins. Keywords: ZnO nanoparticles, biokinetics, distribution, excretion, fate, interaction

  18. Magnetic properties, microstructure and mineralogical phases of technogenic magnetic particles (TMPs) in urban soils: Their source identification and environmental implications

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Shenggao, E-mail: lusg@zju.edu.cn [College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China); Yu, Xiuling [College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China); Chen, Yuyin [Institute of Biological Resources, Zhejiang University, Hangzhou 310058 (China)

    2016-02-01

    Magnetic measurement is an effective method to determine spatial distribution and the degree of heavy metal pollution and to identify various anthropogenic sources of heavy metals. The objectives of this investigation are to characterize the magnetic properties, microstructure and mineralogical phases of technogenic magnetic particles (TMPs) in urban soils and to discuss their potential environmental implications. The TMPs are separated from the urban topsoils of Luoyang city, China. The magnetic properties, morphology, and mineral phase of TMPs are studied using mineral magnetic measurement, scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (SEM/EDS), X-ray diffraction, and synchrotron–radiation-based microprobe. The content of TMPs in urban topsoils ranges from 0.05 to 1.95% (on average 0.32%). The magnetic susceptibility of TMPs ranges from 4559 × 10{sup −8} to 23,661 × 10{sup −8} m{sup 3} kg{sup −1} (on average 13,637 × 10{sup −8} m{sup 3} kg{sup −1}). Thermomagnetic and bulk X-ray diffraction analyses indicate that main magnetic minerals of TMPs are magnetite (Fe{sub 3}O{sub 4}) and hematite (α-Fe{sub 2}O{sub 3}). The morphology of TMPs observed by SEM includes three shape types: spherule, irregular-shaped, and aggregate particles. The size of spherical TMPs ranges from 30 to about 200 μm, with the largest percentage of 30–50 μm. Synchrotron–radiation-based microprobe (μ-XRF and μ-XRD) indicates that TMPs are enriched with heavy metals Pb, Cd, Zn, Cu, and Cr, which are incorporated into lattice or adsorbed on the surface of magnetite/hematite. The content of TMPs significantly relates with the Tomlinson Pollution Load Index (PLI) (R{sup 2} = 0.467), suggesting that it can be used as proxy indicator of degree of heavy metal contamination in urban soils. The magnetic properties, microstructure and mineralogical phases of TMPs can serve as the identification of pollution sources in urban soils. - Graphical

  19. Searching for “Environmentally-Benign” Antifouling Biocides

    Directory of Open Access Journals (Sweden)

    Yan Ting Cui

    2014-05-01

    Full Text Available As the result of the ecological impacts from the use of tributyltins (TBT in shipping, environmental legislation for the registration of chemicals for use in the environment has grown to a monumental challenge requiring product dossiers to include information on the environmental fate and behavior of any chemicals. Specifically, persistence, bioaccumulation and toxicity, collectively known as PBT, are properties of concern in the assessment of chemicals. However, existing measurements of PBT properties are a cumbersome and expensive process, and thus not applied in the early stages of the product discovery and development. Inexpensive methods for preliminary PBT screening would minimize risks arising with the subsequent registration of products. In this article, we evaluated the PBT properties of compounds reported to possess anti-fouling properties using QSAR (quantitative structure-activity relationship prediction programs such as BIOWIN™ (a biodegradation probability program, KOWWIN™ (log octanol-water partition coefficient calculation program and ECOSAR™ (Ecological Structure Activity Relationship Programme. The analyses identified some small (Mr < 400 synthetic and natural products as potential candidates for environmentally benign biocides. We aim to demonstrate that while these methods of estimation have limitations, when applied with discretion, they are powerful tools useful in the early stages of research for compound selection for further development as anti-foulants.

  20. Fate in the religion of the Lepchas

    Directory of Open Access Journals (Sweden)

    Halfdan Siiger

    1967-02-01

    Full Text Available The Lepchas are mountainous agriculturalists who live in the State of Sikkim in the Himalayas and in some adjacent Indian districts. To the Lepchas the supernatural world is divided into two groups, the rum, or the mainly benevolent supernatural beings, and the mung, or the malignant supernatural beings. Any evil occurrence is in the first instance ascribed to the malignant activities of the mung, but it may, under certain conditions, also be due to temporary on the part of some or other rum. If it is obvious that the evil occurrence is caused by a human being, this person is considered to be governed by some mung, or he may, which is much worse, be a mung in human disguise. At all events, any evil occurrence is experienced as the result of the evil will-power of some or other malignant supernatural being. Consequently, we cannot apply our technical term "Fate" to such occurrences, and Fate as an abstract concept cannot be used, when we speak of the Lepchas.

  1. Connecting Mitochondria, Metabolism, and Stem Cell Fate

    Science.gov (United States)

    Wanet, Anaïs; Arnould, Thierry; Najimi, Mustapha

    2015-01-01

    As sites of cellular respiration and energy production, mitochondria play a central role in cell metabolism. Cell differentiation is associated with an increase in mitochondrial content and activity and with a metabolic shift toward increased oxidative phosphorylation activity. The opposite occurs during reprogramming of somatic cells into induced pluripotent stem cells. Studies have provided evidence of mitochondrial and metabolic changes during the differentiation of both embryonic and somatic (or adult) stem cells (SSCs), such as hematopoietic stem cells, mesenchymal stem cells, and tissue-specific progenitor cells. We thus propose to consider those mitochondrial and metabolic changes as hallmarks of differentiation processes. We review how mitochondrial biogenesis, dynamics, and function are directly involved in embryonic and SSC differentiation and how metabolic and sensing pathways connect mitochondria and metabolism with cell fate and pluripotency. Understanding the basis of the crosstalk between mitochondria and cell fate is of critical importance, given the promising application of stem cells in regenerative medicine. In addition to the development of novel strategies to improve the in vitro lineage-directed differentiation of stem cells, understanding the molecular basis of this interplay could lead to the identification of novel targets to improve the treatment of degenerative diseases. PMID:26134242

  2. Fate of Fusarium Toxins during Brewing.

    Science.gov (United States)

    Habler, Katharina; Geissinger, Cajetan; Hofer, Katharina; Schüler, Jan; Moghari, Sarah; Hess, Michael; Gastl, Martina; Rychlik, Michael

    2017-01-11

    Some information is available about the fate of Fusarium toxins during the brewing process, but only little is known about the single processing steps in detail. In our study we produced beer from two different barley cultivars inoculated with three different Fusarium species, namely, Fusarium culmorum, Fusarium sporotrichioides, and Fusarium avenaceum, producing a wide range of mycotoxins such as type B trichothecenes, type A trichothecenes, and enniatins. By the use of multi-mycotoxin LC-MS/MS stable isotope dilution methods we were able to follow the fate of Fusarium toxins during the entire brewing process. In particular, the type B trichothecenes deoxynivalenol, 3-acetyldeoxynivalenol, and 15-acetyldeoxynivalenol showed similar behaviors. Between 35 and 52% of those toxins remained in the beer after filtration. The contents of the potentially hazardous deoxynivalenol-3-glucoside and the type A trichothecenes increased during mashing, but a rapid decrease of deoxynivalenol-3-glucoside content was found during the following steps of lautering and wort boiling. The concentration of enniatins greatly decreased with the discarding of spent grains or finally with the hot break. The results of our study show the retention of diverse Fusarium toxins during the brewing process and allow for assessing the food safety of beer regarding the monitored Fusarium mycotoxins.

  3. Glucocorticoid regulation of astrocytic fate and function.

    Directory of Open Access Journals (Sweden)

    Shuang Yu

    Full Text Available Glial loss in the hippocampus has been suggested as a factor in the pathogenesis of stress-related brain disorders that are characterized by dysregulated glucocorticoid (GC secretion. However, little is known about the regulation of astrocytic fate by GC. Here, we show that astrocytes derived from the rat hippocampus undergo growth inhibition and display moderate activation of caspase 3 after exposure to GC. Importantly, the latter event, observed both in situ and in primary astrocytic cultures is not followed by either early- or late-stage apoptosis, as monitored by stage I or stage II DNA fragmentation. Thus, unlike hippocampal granule neurons, astrocytes are resistant to GC-induced apoptosis; this resistance is due to lower production of reactive oxygen species (ROS and a greater buffering capacity against the cytotoxic actions of ROS. We also show that GC influence hippocampal cell fate by inducing the expression of astrocyte-derived growth factors implicated in the control of neural precursor cell proliferation. Together, our results suggest that GC instigate a hitherto unknown dialog between astrocytes and neural progenitors, adding a new facet to understanding how GC influence the cytoarchitecture of the hippocampus.

  4. Endothelial ERK signaling controls lymphatic fate specification

    Science.gov (United States)

    Deng, Yong; Atri, Deepak; Eichmann, Anne; Simons, Michael

    2013-01-01

    Lymphatic vessels are thought to arise from PROX1-positive endothelial cells (ECs) in the cardinal vein in response to induction of SOX18 expression; however, the molecular event responsible for increased SOX18 expression has not been established. We generated mice with endothelial-specific, inducible expression of an RAF1 gene with a gain-of-function mutation (RAF1S259A) that is associated with Noonan syndrome. Expression of mutant RAF1S259A in ECs activated ERK and induced SOX18 and PROX1 expression, leading to increased commitment of venous ECs to the lymphatic fate. Excessive production of lymphatic ECs resulted in lymphangiectasia that was highly reminiscent of abnormal lymphatics seen in Noonan syndrome and similar “RASopathies.” Inhibition of ERK signaling during development abrogated the lymphatic differentiation program and rescued the lymphatic phenotypes induced by expression of RAF1S259A. These data suggest that ERK activation plays a key role in lymphatic EC fate specification and that excessive ERK activation is the basis of lymphatic abnormalities seen in Noonan syndrome and related diseases. PMID:23391722

  5. The influence of climate change on the global distribution and fate processes of anthropogenic persistent organic pollutants.

    Science.gov (United States)

    Kallenborn, Roland; Halsall, Crispin; Dellong, Maud; Carlsson, Pernilla

    2012-11-01

    The effect of climate change on the global distribution and fate of persistent organic pollutants (POPs) is of growing interest to both scientists and policy makers alike. The impact of warmer temperatures and the resulting changes to earth system processes on chemical fate are, however, unclear, although there are a growing number of studies that are beginning to examine these impacts and changes in a quantitative way. In this review, we examine broad areas where changes are occurring or are likely to occur with regard to the environmental cycling and fate of chemical contaminants. For this purpose we are examining scientific information from long-term monitoring data with particular emphasis on the Arctic, to show apparent changes in chemical patterns and behaviour. In addition, we examine evidence of changing chemical processes for a number of environmental compartments and indirect effects of climate change on contaminant emissions and behaviour. We also recommend areas of research to address knowledge gaps. In general, our findings indicate that the indirect consequences of climate change (i.e. shifts in agriculture, resource exploitation opportunities, etc.) will have a more marked impact on contaminants distribution and fate than direct climate change.

  6. Investigating undergraduate students' ideas about the fate of the Universe

    Science.gov (United States)

    Conlon, Mallory; Coble, Kim; Bailey, Janelle M.; Cominsky, Lynn R.

    2017-12-01

    As astronomers further develop an understanding of the fate of the Universe, it is essential to study students' ideas on the fate of the Universe so that instructors can communicate the field's current status more effectively. In this study, we examine undergraduate students' preinstruction ideas of the fate of the Universe in ten semester-long introductory astronomy course sections (ASTRO 101) at three institutions. We also examine students' postinstruction ideas about the fate of the Universe in ASTRO 101 over five semester-long course sections at one institution. The data include precourse surveys given during the first week of instruction (N =264 ), postinstruction exam questions (N =59 ), and interviews. We find that, preinstruction, more than a quarter of ASTRO 101 students either do not respond or respond with "I don't know" when asked what the long-term fate of the Universe is. We also find that, though the term was not necessarily used, students tend to describe a "big chill" scenario in the preinstruction surveys, among a wide variety of other scenarios. A fraction of students describe the fate of smaller-scale systems, possibly due to confusion of the hierarchical nature of structure in the Universe. Preinstruction, students mention the Universe's expansion when describing how astronomers know the fate of the Universe but do not discuss how we know the Universe is expanding or the relationship between expansion and the fate of the Universe. Postinstruction, students' responses shift toward greater degrees of completeness and correctness.

  7. Cell fate determination in the Caenorhabditis elegans epidermal lineages

    NARCIS (Netherlands)

    Soete, G.A.J.

    2007-01-01

    The starting point for this work was to use the hypodermal seam of C. elegans as a model system to study cell fate determination. Even though the seam is a relatively simple developmental system, the mechanisms that control cell fate determination in the seam lineages are connected in a highly

  8. Application of nanoparticle tracking analysis for characterising the fate of engineered nanoparticles in sediment-water systems.

    Science.gov (United States)

    Luo, Ping; Roca, Alejandro; Tiede, Karen; Privett, Katie; Jiang, Jiachao; Pinkstone, John; Ma, Guibin; Veinot, Jonathan; Boxall, Alisatair

    2018-02-01

    Novel applications of nanotechnology may lead to the release of engineered nanoparticles (ENPs), which result in concerns over their potential environmental hazardous impact. It is essential for the research workers to be able to quantitatively characterise ENPs in the environment and subsequently to assist the risk assessment of the ENPs. This study hence explored the application of nanoparticle tracking system (NTA) to quantitatively describe the behaviour of the ENPs in natural sediment-water systems. The NTA allows the measurement of both particle number concentration (PNC) and particle size distribution (PSD) of the ENPs. The developed NTA method was applied to a range of gold and magnetite ENPs with a selection of surface properties. The results showed that the positively-charged ENPs interacted more strongly with the sediment than neutral and negatively-charged ENPs. It was also found that the citrate coated Au ENPs had a higher distribution percentage (53%) than 11-mercaptoundecanoic acid coated Au ENPs (20%) and citrate coated magnetite ENPs (21%). The principles of the electrostatic interactions between hard (and soft) acids and bases (HSAB) are used to explain such behaviours; the hard base coating (i.e. citrate ions) will interact more strongly with hard acid (i.e. magnetite) than soft acid (i.e. gold). The results indicate that NTA is a complementary method to existing approaches to characterise the fate and behaviour of ENPs in natural sediment. Copyright © 2017. Published by Elsevier B.V.

  9. Elucidation of Environmental Fate of Artificial Sweetener, Aspartame by Determining Bimolecular Rate Constants with Hydroxyl Radical at Various pH and Temperature Conditions and Reaction By-Products Presentation type:Poster Section:Ocean Sciences Session:General Contribution Authors:Takashi Teraji (1) Takemitsu Arakaki (2) AGU# 10173629 (1) Graduate School of Engineering and Science, University of the Ryukyus, 1 Senbaru Nishihara-cho, Okinawa, 903-0123, Japan (a4269bj@yahoo.co.jp), (2) Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, 1 Senbaru Nishihara-cho, Okinawa, 903-0123, Japan (arakakit@sci.u-ryukyu.ac.jp)

    Science.gov (United States)

    Teraji, T.; Arakaki, T.

    2011-12-01

    Use of artificial sweeteners in drinks and food has been rapidly increasing because of their non-calorie nature. In Japan, aspartame, acesulfame K and sucralose are among the most widely used artificial sweeteners. Because the artificial sweeteners are not metabolized in human bodies, they are directly excreted into the environment without chemical transformations. We initiated a study to better understand the fate of artificial sweeteners in the marine environment. In particular, we focused on the fate of aspartame by determining its bimolecular rate constants with hydroxyl radicals at various pH and temperature conditions and reaction by-products. The hydroxyl radical (OH), the most potent reactive oxygen species, reacts with various compounds and determines the environmental oxidation capacity and the life-time of many compounds. The steady-state OH concentration and the reaction rate constants between the compound and OH are used to estimate the life-time of the compound. In this study, we determine the bimolecular rate constants between aspartame and OH at various pH and temperature conditions using a competition kinetics technique. We use hydrogen peroxide as a photochemical source of OH. Bimolecular rate constant we obtained so far was (2.6±1.2)×109 M-1 s-1 at pH = 3.0. Little effect was seen by changing the temperatures between 15 and 40 °C. Activation energy (Ea) was calculated to be -1.0 kJ mol-1 at pH = 3.0, which could be regarded as zero. We will report reaction rate constants at different pHs and reaction by-products which will be analyzed by GC-MS. We will further discuss the fate of aspartame in the coastal environment.

  10. Asymmetric cell division during T cell development controls downstream fate

    Science.gov (United States)

    Pham, Kim; Shimoni, Raz; Charnley, Mirren; Ludford-Menting, Mandy J.; Hawkins, Edwin D.; Ramsbottom, Kelly; Oliaro, Jane; Izon, David; Ting, Stephen B.; Reynolds, Joseph; Lythe, Grant; Molina-Paris, Carmen; Melichar, Heather; Robey, Ellen; Humbert, Patrick O.; Gu, Min

    2015-01-01

    During mammalian T cell development, the requirement for expansion of many individual T cell clones, rather than merely expansion of the entire T cell population, suggests a possible role for asymmetric cell division (ACD). We show that ACD of developing T cells controls cell fate through differential inheritance of cell fate determinants Numb and α-Adaptin. ACD occurs specifically during the β-selection stage of T cell development, and subsequent divisions are predominantly symmetric. ACD is controlled by interaction with stromal cells and chemokine receptor signaling and uses a conserved network of polarity regulators. The disruption of polarity by deletion of the polarity regulator, Scribble, or the altered inheritance of fate determinants impacts subsequent fate decisions to influence the numbers of DN4 cells arising after the β-selection checkpoint. These findings indicate that ACD enables the thymic microenvironment to orchestrate fate decisions related to differentiation and self-renewal. PMID:26370500

  11. Environmental biochemistry of chromium.

    Science.gov (United States)

    Losi, M E; Amrhein, C; Frankenberger, W T

    1994-01-01

    Chromium is a d-block transitional element with many industrial uses. It occurs naturally in various crustal materials and is discharged to the environment as industrial waste. Although it can occur in a number of oxidation states, only 3+ and 6+ are found in environmental systems. The environmental behavior of Cr is largely a function of its oxidation state. Hexavalent Cr compounds (mainly chromates and dichromates) are considered toxic to a variety of terrestrial and aquatic organisms and are mobile in soil/water systems, much more so than trivalent Cr compounds. This is largely because of differing chemical properties: Hexavalent Cr compounds are strong oxidizers and highly soluble, while trivalent Cr compounds tend to form relatively inert precipitates at near-neutral pH. The trivalent state is generally considered to be the stable form in equilibrium with most soil/water systems. A diagram of the Cr cycle in soils and water is given in Fig. 6 (Bartlett 1991). This illustration provides a summary of environmentally relevant reactions. Beginning with hexavalent Cr that is released into the environment as industrial waste, there are a number of possible fates, including pollution of soil and surface water and leaching into groundwater, where it may remain stable and, in turn, can be taken up by plants or animals, and adsorption/precipitation, involving soil colloids and/or organic matter. Herein lies much of the environmental concern associated with the hexavalent form. A portion of the Cr(VI) will be reduced to the trivalent form by inorganic electron donors, such as Fe2+ and S2-, or by bioprocesses involving organic matter. Following this conversion, Cr3+ can be expected to precipitate as oxides and hydroxides or to form complexes with numerous ligands. This fraction includes a vast majority of global Cr reserves. Soluble Cr3+ complexes, such as those formed with citrate, can undergo oxidation when they come in contact with manganese dioxide, thus reforming

  12. Investigation of mono/competitive adsorption of environmentally relevant ionized weak acids on graphite: impact of molecular properties and thermodynamics.

    Science.gov (United States)

    Moustafa, Ahmed M A; McPhedran, Kerry N; Moreira, Jesús; Gamal El-Din, Mohamed

    2014-12-16

    The thermodynamics of adsorption and competitive interactions of five weak acids on a graphite surface was assessed in alkaline solutions. Adsorption of the acids in mono- and multicompound solutions followed their Freundlich isotherms which suggest a diversity of graphite adsorption sites as confirmed by the presence of carboxylic and phenolic groups observed on graphite surfaces. Thermodynamic calculations assigned the formation of the negatively charged assisted hydrogen bond (-CAHB) between ionized solutes and adsorbent surface groups as the possible adsorption mechanism. However, the similar pKa values of current acids resulted in comparable free energies for -CAHB formation (ΔG(-CAHB)) being less than solvation free energies (ΔGSolv). Thus, additional ΔG is supplemented by increased hydrophobicity due to proton exchange of ionized acids with water (ΔΔG Hydrophobicity). Adsorption capacities and competition coefficients indicated that ΔΔG Hydrophobicity values depend on the neutral and ionized acid Kow. Competitive adsorption implies that multilayer adsorption may occur via hydrophobic bonding with the CH3 ends of the self-assembled layer which affects the acid adsorption capacities in mixtures as compared to monocompound solutions. The determination of adsorption mechanisms will assist in understanding of the fate and bioavailability of emerging and classical weak acids released into natural waters.

  13. Modelling impact of climate change on atmospheric transport and fate of persistent organic pollutants in the Arctic

    Science.gov (United States)

    Hansen, K. M.; Christensen, J. H.; Geels, C.; Silver, J. D.; Brandt, J.

    2015-03-01

    The Danish Eulerian Hemispheric Model (DEHM) was applied to investigate how projected climate changes will affect the atmospheric transport of 13 persistent organic pollutants (POPs) to the Artic and their environmental fate within the Arctic. Two sets of simulations were performed, one with initial environmental concentrations from a 20 year spin-up simulation and one with initial environmental concentrations set to zero. Each set of simulations consisted of two ten-year time slices representing the present (1990-2000) and future (2090-2100) climate conditions. The same POP emissions were applied in all simulations to ensure that the difference in predicted concentrations for each set of simulations only arises from the difference in climate input. DEHM was driven using meteorological input from the global circulation model, ECHAM/MPI-OM, simulating the SRES A1B climate scenario. Under the applied climate and emission scenarios, the total mass of all compounds was predicted to be up to 20% higher across the Northern Hemisphere. The mass of HCHs within the Arctic was predicted to be up to 39% higher, whereas the change in mass of the PCBs was predicted to range from 14% lower to 17% higher depending on the congener and the applied initial environmental concentrations. The results of this study also indicate that contaminants with no or a short emission history will be more rapidly transported to and build up in the arctic environment in a future warmer climate. The process that dominates the environmental behaviour of POPs in the Arctic under a future warmer climate scenario is the shift in mass of POPs from the surface media to the atmosphere induced by the higher mean temperature. This is to some degree counteracted by higher degradation rates also following the higher mean temperature. The more dominant of these two processes depend on the physical-chemical properties of the compounds. Previous model studies have predicted that the effect of a changed climate on

  14. The fate and importance of radionuclides produced in nuclear events

    Energy Technology Data Exchange (ETDEWEB)

    Shore, B; Anspaugh, L; Chertok, R; Gofman, J; Harrison, F; Heft, R; Koranda, J; Ng, Y; Phelps, P; Potter, G; Tamplin, A [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

    1969-07-01

    Some of the major program at the Bio-Medical Division concerned with the fate and importance of the fission products, the radionuclides induced in the device materials, the radionuclides induced in the environment surrounding the device, and the tritium produced in Plowshare cratering events will be discussed. These programs include (1) critical unknowns in predicting organ and body burdens from radionuclides produced in cratering events; (2) the analysis with a high-resolution solid state gamma ray spectrometer of radionuclides in complex biological and environmental samples; (3) the characterization of radioactive particles from cratering detonation; (4) the biological availability to beagles, pigs and goats of radionuclides in Plowshare debris; (5) the biological availability to aquatic animals of radionuclides in Plowshare and other nuclear debris and the biological turnover of critical nuclides in specific aquatic animals; (6) the biological availability of Plowshare and other nuclear debris radionuclides to dairy cows and the transplacental transport of debris radionuclides in the dairy cow; (7) the persistence and behavior of radionuclides, particularly tritium, at sites of Plowshare and other nuclear detonations; and (8) somatic effects of Low Dose Radiation: Chromosome studies. (author)

  15. Selenium uptake, translocation, assimilation and metabolic fate in plants.

    Science.gov (United States)

    Sors, T G; Ellis, D R; Salt, D E

    2005-12-01

    The chemical and physical resemblance between selenium (Se) and sulfur (S) establishes that both these elements share common metabolic pathways in plants. The presence of isologous Se and S compounds indicates that these elements compete in biochemical processes that affect uptake, translocation and assimilation throughout plant development. Yet, minor but crucial differences in reactivity and other metabolic interactions infer that some biochemical processes involving Se may be excluded from those relating to S. This review examines the current understanding of physiological and biochemical relationships between S and Se metabolism by highlighting their similarities and differences in relation to uptake, transport and assimilation pathways as observed in Se hyperaccumulator and non-accumulator plant species. The exploitation of genetic resources used in bioengineering strategies of plants is illuminating the function of sulfate transporters and key enzymes of the S assimilatory pathway in relation to Se accumulation and final metabolic fate. These strategies are providing the basic framework by which to resolve questions relating to the essentiality of Se in plants and the mechanisms utilized by Se hyperaccumulators to circumvent toxicity. In addition, such approaches may assist in the future application of genetically engineered Se accumulating plants for environmental renewal and human health objectives.

  16. The fate and importance of radionuclides produced in nuclear events

    International Nuclear Information System (INIS)

    Shore, B.; Anspaugh, L.; Chertok, R.; Gofman, J.; Harrison, F.; Heft, R.; Koranda, J.; Ng, Y.; Phelps, P.; Potter, G.; Tamplin, A.

    1969-01-01

    Some of the major program at the Bio-Medical Division concerned with the fate and importance of the fission products, the radionuclides induced in the device materials, the radionuclides induced in the environment surrounding the device, and the tritium produced in Plowshare cratering events will be discussed. These programs include (1) critical unknowns in predicting organ and body burdens from radionuclides produced in cratering events; (2) the analysis with a high-resolution solid state gamma ray spectrometer of radionuclides in complex biological and environmental samples; (3) the characterization of radioactive particles from cratering detonation; (4) the biological availability to beagles, pigs and goats of radionuclides in Plowshare debris; (5) the biological availability to aquatic animals of radionuclides in Plowshare and other nuclear debris and the biological turnover of critical nuclides in specific aquatic animals; (6) the biological availability of Plowshare and other nuclear debris radionuclides to dairy cows and the transplacental transport of debris radionuclides in the dairy cow; (7) the persistence and behavior of radionuclides, particularly tritium, at sites of Plowshare and other nuclear detonations; and (8) somatic effects of Low Dose Radiation: Chromosome studies. (author)

  17. Fate of dispersants associated with the deepwater horizon oil spill.

    Science.gov (United States)

    Kujawinski, Elizabeth B; Kido Soule, Melissa C; Valentine, David L; Boysen, Angela K; Longnecker, Krista; Redmond, Molly C

    2011-02-15

    Response actions to the Deepwater Horizon oil spill included the injection of ∼771,000 gallons (2,900,000 L) of chemical dispersant into the flow of oil near the seafloor. Prior to this incident, no deepwater applications of dispersant had been conducted, and thus no data exist on the environmental fate of dispersants in deepwater. We used ultrahigh resolution mass spectrometry and liquid chromatography with tandem mass spectrometry (LC/MS/MS) to identify and quantify one key ingredient of the dispersant, the anionic surfactant DOSS (dioctyl sodium sulfosuccinate), in the Gulf of Mexico deepwater during active flow and again after flow had ceased. Here we show that DOSS was sequestered in deepwater hydrocarbon plumes at 1000-1200 m water depth and did not intermingle with surface dispersant applications. Further, its concentration distribution was consistent with conservative transport and dilution at depth and it persisted up to 300 km from the well, 64 days after deepwater dispersant applications ceased. We conclude that DOSS was selectively associated with the oil and gas phases in the deepwater plume, yet underwent negligible, or slow, rates of biodegradation in the affected waters. These results provide important constraints on accurate modeling of the deepwater plume and critical geochemical contexts for future toxicological studies.

  18. An Comparative Study of Jane Eyre's Fate and Tess's Fate from Femi?nist Viewpoint

    Institute of Scientific and Technical Information of China (English)

    CHEN Jing; HE Ling-jing

    2017-01-01

    In"Jane Eyre", Charlotte Bronte's masterpiece the heroine, Jane Eyre has fully reflected her self-esteem, equality, and pure personality, which are also reflected in her concept of love vividly. However, Thomas Hardy's Tess is poor and kind, but she does not have a complete love like Jane Eyre, and she is described by his criticism of the old moral character with good vir-tues in the traditional sense. She is a new image of modern feminism who suffered from the old moral sense and gradually has re-volt consciousness. From the feminism viewpoint, this paper attempts to analysis the causes of their different fate from different points and reveal the impact of social background on their fates.

  19. C. Linnaeus' ideas concerning retribution and fate

    Directory of Open Access Journals (Sweden)

    K. Rob. V. Wikman

    1967-02-01

    Full Text Available Linnæus' Nemesis divina has been interpreted in different ways. Crucial is its central problem: the ideas of fate and retribution, but these are, in turn, dependent on Linnæus' conception of God and nature and not least on his opinions concerning the unity and coherence of the natural and ethical order of the world. From whatever sources Linnæus may have derived his religious ideas and whatever changes they may have undergone, his religious attitude in face of the works of nature remained unshaken. But Linnæus' religion, as we find it fragmentarily in these literary sources, was entirely undogmatic, untheological and, from a Christian point of view, even heterodox. Partly, this was in accord with his belief in the necessary immanent coherence in the processes of nature and the concomitant idea of the righteous divine order of the world.

  20. The fate of radioactivity in sewers

    International Nuclear Information System (INIS)

    2000-01-01

    The Environment Agencies authorise and monitor the disposal of low-level radioactive waste to sewers. Such discharges originate from non-nuclear sites such as hospitals, universities and research centres. Discharges are strictly controlled through authorisations, which place conditions and limits on the disposer. We commissioned the work summarised within this, leaflet to reassess the fate of these radioactive discharges and to ensure that this practice remains acceptable and is still the best option for disposal. In all cases the study found assessed radiation doses (associated with these discharges) to be a small fraction of the public dose limit. The Environment Agencies conclude from this study that the disposal of radioactive waste to sewers remains the best option available to ensure the safety of the public (including sewer workers) and to protect the environment

  1. The Fate of Job in Jewish Tradition

    DEFF Research Database (Denmark)

    Schleicher, Marianne

    2008-01-01

    to a few examples of the fate of Job in Jewish tradition and concerned with Scripture's role with respect to religious normativity, this article will be guided by the following question: How can The Book of Job maintain its role within Jewish tradition as a normative text? My reading suggests that The Book......Job's piety in The Book of Job is so ideal that it becomes problematic on two levels. First, it renders God a tyrant. Second, no one can fully identify with Job. Surely, we may suffer just as much as Job does and even feel that God is unjust, but no man can ever claim to be as pious as Job. Limited...... of Job in itself is not normative. Rather, it serves as a counterpoint up against which the reception and transformation of Jewish theology can unfold and as such The Book of Job exerts its function on Jewish religiosity....

  2. A D Sakharov: personality and fate

    International Nuclear Information System (INIS)

    Ritus, Vladimir I

    2012-01-01

    A D Sakharov was an amazingly gifted person for whom, with his combined talents as a physicist and inventor, ''physical laws and the relation among phenomena were directly visualized and tangible in all their inherent simplicity'' (I E Tamm). The author of the key ideas involved in the hydrogen weapons and fusion reactor programs, and well aware of his scientific and public status, Sakharov was, nevertheless, a modest and highly decent man, always trustful of people in discussing their or his problems. Although his greatest satisfaction lay in successfully solving fundamental problems in physics and cosmology, fate and duty made him turn to matters of universal human significance, particularly human rights, to the gruelling struggle to which he devoted many years of his life. (conferences and symposia)

  3. The Fate of Neutron Star Binary Mergers

    Energy Technology Data Exchange (ETDEWEB)

    Piro, Anthony L. [The Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Giacomazzo, Bruno [Physics Department, University of Trento, via Sommarive 14, I-38123 Trento (Italy); Perna, Rosalba, E-mail: piro@carnegiescience.edu [Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794 (United States)

    2017-08-01

    Following merger, a neutron star (NS) binary can produce roughly one of three different outcomes: (1) a stable NS, (2) a black hole (BH), or (3) a supramassive, rotationally supported NS, which then collapses to a BH following angular momentum losses. Which of these fates occur and in what proportion has important implications for the electromagnetic transient associated with the mergers and the expected gravitational wave (GW) signatures, which in turn depend on the high density equation of state (EOS). Here we combine relativistic calculations of NS masses using realistic EOSs with Monte Carlo population synthesis based on the mass distribution of NS binaries in our Galaxy to predict the distribution of fates expected. For many EOSs, a significant fraction of the remnants are NSs or supramassive NSs. This lends support to scenarios in which a quickly spinning, highly magnetized NS may be powering an electromagnetic transient. This also indicates that it will be important for future GW observatories to focus on high frequencies to study the post-merger GW emission. Even in cases where individual GW events are too low in signal to noise to study the post merger signature in detail, the statistics of how many mergers produce NSs versus BHs can be compared with our work to constrain the EOS. To match short gamma-ray-burst (SGRB) X-ray afterglow statistics, we find that the stiffest EOSs are ruled out. Furthermore, many popular EOSs require a significant fraction of ∼60%–70% of SGRBs to be from NS–BH mergers rather than just binary NSs.

  4. Modelling the fate of persistent organic pollutants in Europe: parameterisation of a gridded distribution model

    International Nuclear Information System (INIS)

    Prevedouros, Konstantinos; MacLeod, Matthew; Jones, Kevin C.; Sweetman, Andrew J.

    2004-01-01

    A regionally segmented multimedia fate model for the European continent is described together with an illustrative steady-state case study examining the fate of γ-HCH (lindane) based on 1998 emission data. The study builds on the regionally segmented BETR North America model structure and describes the regional segmentation and parameterisation for Europe. The European continent is described by a 5 deg. x 5 deg. grid, leading to 50 regions together with four perimetric boxes representing regions buffering the European environment. Each zone comprises seven compartments including; upper and lower atmosphere, soil, vegetation, fresh water and sediment and coastal water. Inter-regions flows of air and water are described, exploiting information originating from GIS databases and other georeferenced data. The model is primarily designed to describe the fate of Persistent Organic Pollutants (POPs) within the European environment by examining chemical partitioning and degradation in each region, and inter-region transport either under steady-state conditions or fully dynamically. A test case scenario is presented which examines the fate of estimated spatially resolved atmospheric emissions of lindane throughout Europe within the lower atmosphere and surface soil compartments. In accordance with the predominant wind direction in Europe, the model predicts high concentrations close to the major sources as well as towards Central and Northeast regions. Elevated soil concentrations in Scandinavian soils provide further evidence of the potential of increased scavenging by forests and subsequent accumulation by organic-rich terrestrial surfaces. Initial model predictions have revealed a factor of 5-10 underestimation of lindane concentrations in the atmosphere. This is explained by an underestimation of source strength and/or an underestimation of European background levels. The model presented can further be used to predict deposition fluxes and chemical inventories, and it

  5. Influence of environmental factors on the contents of active ingredients and radical scavenging property of potentilla fruticosa in the main production areas of China

    International Nuclear Information System (INIS)

    Liu, W.; Yin, D. X.; Wang, D. M.; Li, D. W.

    2015-01-01

    Extracts from Potentilla fruticosa have been applied in traditional medicine and exhibited antioxidant property, but little has been known about the diversity of phytochemicals and properties on this species from different growing environment. This study investigated the influence of environmental factors on the active ingredient contents and radical scavenging property of P. fruticosa from different production areas of China in order to discover a location could produce high-quality resources for pharmaceutical products. The contents of tannin, total flavonoids, and rutin were determined and varied within the range of 7.64 ± 0.43 ∼ 10.68 ± 0.67 percentage, 2.29 ± 0.34 ∼ 5.37 ± 0.36 percentage, and 0.19 ± 0.053 ∼ 0.79 ± 0.125 percentage, respectively. Radical scavenging property was quantified, with the IC /sub 50/ of 7.24 ± 0.423 to 17.23 ± 0.551 μ g mL-1. Principal component analysis, multiple linear stepwise regression analysis, and path analysis were conducted to further analysis the relationship between the variations of active ingredients and radical scavenging capacity and growth environment. The results showed dominant environmental factors for these variations were rapidly available nitrogen, rapidly available phosphorus, pH, July average temperature, and annual sunshine duration. Furthermore, a significant positive correlation was observed between pH, annual sunshine duration and active ingredients and radical scavenging property (p<0.05). Considering the high active ingredient contents and strong radical scavenging property, leaf extracts from P. fruticosa could become useful supplements for pharmaceutical products as a new antioxidant agent, and Huzhu Northern Mountain in Qinghai Province and E-mei Mountain in Sichuan Province were selected as favorable production locations. (author)

  6. Sympathetic Innervation Promotes Arterial Fate by Enhancing Endothelial ERK Activity.

    Science.gov (United States)

    Pardanaud, Luc; Pibouin-Fragner, Laurence; Dubrac, Alexandre; Mathivet, Thomas; English, Isabel; Brunet, Isabelle; Simons, Michael; Eichmann, Anne

    2016-08-19

    Arterial endothelial cells are morphologically, functionally, and molecularly distinct from those found in veins and lymphatic vessels. How arterial fate is acquired during development and maintained in adult vessels is incompletely understood. We set out to identify factors that promote arterial endothelial cell fate in vivo. We developed a functional assay, allowing us to monitor and manipulate arterial fate in vivo, using arteries isolated from quails that are grafted into the coelom of chick embryos. Endothelial cells migrate out from the grafted artery, and their colonization of host arteries and veins is quantified. Here we show that sympathetic innervation promotes arterial endothelial cell fate in vivo. Removal of sympathetic nerves decreases arterial fate and leads to colonization of veins, whereas exposure to sympathetic nerves or norepinephrine imposes arterial fate. Mechanistically, sympathetic nerves increase endothelial ERK (extracellular signal-regulated kinase) activity via adrenergic α1 and α2 receptors. These findings show that sympathetic innervation promotes arterial endothelial fate and may lead to novel approaches to improve arterialization in human disease. © 2016 American Heart Association, Inc.

  7. Avaliação de herbicidas aplicados em pós-emergência sobre e sob a palha em cana crua e o destino ambiental Evaluation of herbicides applied in post-emergence over and under straw in no-burn sugarcane and their environmental fate

    Directory of Open Access Journals (Sweden)

    L.L. Foloni

    2011-06-01

    eficientes no controle das principais plantas daninhas presentes. A aplicação desses herbicidas sobre ou sob a palhada da cana crua não mostrou diferença na eficiência de controle ou sobre os demais parâmetros avaliados. A aplicação do modelo de fugacidade objetivando avaliar o comportamento preferencial mostrou que todos os herbicidas tendem a ter maior distribuição no compartimento água.This study aimed to evaluate the efficiency of several herbicides, applied alone or mixed in post-emergence on ratoon sugarcane crop, mechanically harvested under a no-burn system, to assess differences in performance when applied over or under the straw. In addition, based on the concept of sustainability and environmental risk evaluation, mathematical models were used to evaluate the fate of these herbicides. The experiment was carried out in the municipality of Bariri-SP, in the Della Colletta Processing Plant section of Santo Antonio Farm's sugarcane (RB 72 754 cultivar cultivated areas. Ratoon sugarcane was planted with 1.40 m spacing on Red-Yellow Argisol soils with 5% declivity. The experiment was arranged in a randomized block design in 14 plots (trifloxulfurom-sodium+ametryn 720 and 960; mesotrione 192 and 292.6; mesotrione and ametryn 292.6+1500; mesotrione+trifloxysulfuron-sodium 182.8+720; metribuzin 2680; trifloxysulfuron-sodium+ametryn+hexazinone+diuron 720+900; amicarbazine 45; hexazinone+diuron 1320; trifloxysulfuron-sodium+sulfentrazone 720+700 (all of the above cited in grams of active ingredients; control; weeded control, and four replicates, for each type of application (over or under the straw, side by side. The following evaluations were carried out: phytotoxicity, height, stand, efficiency of control of Digitaria horizontalis, Cenchrus echinatus, Emilia fosbergii and Sida cordifolia, number of stalks and first stalk. A fugacity-level I mathematical model was used including the following compartments: air, water, soil, sediment, biota, strain, leaves and

  8. A Critical Analysis of the Environmental Dossiers from the OECD Sponsorship Programme for the Testing of Manufactured Nanomaterials

    DEFF Research Database (Denmark)

    Hansen, Steffen Foss; Hjorth, Rune; Skjolding, Lars Michael

    2017-01-01

    In 2015, the OECD finally published the findings of its seven year testing programme for manufactured nanomaterials. Here, we present the first in-depth analysis of the published OECD dossiers with regards to data on physical and chemical properties, environmental fate and ecotoxicology. Each...... prior, during and/or at the end of the study. We find that the information in the dossiers present an incomplete portfolio of nanomaterial ecotoxicological evaluations that are difficult to draw substantive conclusions from and that most of the studies were not designed to investigate the validity...

  9. Fate of 7,12-dimethylbenz(a)anthracene in rainbow trout, Salmo gairdneri

    International Nuclear Information System (INIS)

    Schnitz, A.R.; Squibb, K.S.; O'Connor, J.M.

    1987-01-01

    Polycyclic aromatic hydrocarbons (PAH) are contaminants of surface waters and sediments, especially near urban centers. Although aquatic biota accumulate PAHs from environmental sources, metabolism may be rapid, and biota sampled from contaminated areas often have concentrations lower than might be estimated from bioconcentration factors. In some cases PAH metabolism by aquatic biota may create reactive intermediates, some of which have been related to chronic effects in fishes. This report describes the fate and distribution of 7,12-dimethylbenz(a)anthracene (DMBA) after oral administration to rainbows trout (Salmo gairdneri). Emphasis has been placed on the disposition of DMBA among tissues and on DMBA transformation in the hepatobiliary system

  10. Main Achievements 2003-2004 - Interdisciplinary Research - Applications of nuclear methods to biomedical physics, environmental biology, environmental physics, and medical physics - Mechanical properties of living cells

    International Nuclear Information System (INIS)

    2005-01-01

    Mechanical properties of living cells, as potential markers of pathological cell state, were investigated in their native environment by atomic force microscopy. In normal and pathological living cells, local elasticity and the specific binding interactions between biomolecules were measured, showing that the interaction force between lectins (ConA, SNA, PHA-L) and cell surface carbohydrates was altered due to cancerous transformation. In further collaboration with the Collegium Medicum of the Jagiellonian University, the elasticity of large number of blood samples, originated from healthy and hospitalized patients, was studied as a first attempt at applying AFM as a tool in medical diagnostics

  11. Nanomaterials in the environment: Behavior, fate, bioavailability, and effects—An updated review

    Science.gov (United States)

    Lead, Jamie R.; Batley, Graeme E.; Alvarez, Pedro J.J.; Croteau, Marie-Noele; Handy, Richard D.; McLaughlin, Michael J.; Judy, Jonathon D.; Schirmer, Kristin

    2018-01-01

    This review covers developments in studies of nanomaterials (NMs) in the environment, since the much‐cited review of Klaine et al. (2008). It discusses novel insights on fate and behavior, metrology, transformations, bioavailability, toxicity mechanisms and environmental impacts, with a focus on terrestrial and aquatic systems. Overall the findings were that: i) despite the substantial developments, there remain critical gaps, in large part due to the lack of analytical, modelling and field capabilities and in part due to the breadth and complexity of the area; ii) a key knowledge gap is the lack of data on environmental concentrations and dosimetry generally; iii) there is substantial evidence that there are nano‐specific effects (different from both ions and larger particles) in the environment in terms of fate, bioavailability and toxicity, but this is not consistent for all NMs, species and all relevant processes; iv) a paradigm is emerging that NMs are less toxic than equivalent dissolved materials but more toxic than the corresponding bulk materials; v) translation of incompletely understood science into regulation and policy continues to be challenging. There is a developing consensus that NMs may pose a relatively low environmental risk, however, with the uncertainty and lack of data in many areas, definitive conclusions cannot be drawn. In addition, this emerging consensus will likely change rapidly with qualitative changes in the technology and increased future discharges. 

  12. Human mammary progenitor cell fate decisions are products of interactions with combinatorial microenvironments

    Energy Technology Data Exchange (ETDEWEB)

    LaBarge, Mark A; Nelson, Celeste M; Villadsen, Rene; Fridriksdottir, Agla; Ruth, Jason R; Stampfer, Martha R; Petersen, Ole W; Bissell, Mina J

    2008-09-19

    In adult tissues, multi-potent progenitor cells are some of the most primitive members of the developmental hierarchies that maintain homeostasis. That progenitors and their more mature progeny share identical genomes, suggests that fate decisions are directed by interactions with extrinsic soluble factors, ECM, and other cells, as well as physical properties of the ECM. To understand regulation of fate decisions, therefore, would require a means of understanding carefully choreographed combinatorial interactions. Here we used microenvironment protein microarrays to functionally identify combinations of cell-extrinsic mammary gland proteins and ECM molecules that imposed specific cell fates on bipotent human mammary progenitor cells. Micropatterned cell culture surfaces were fabricated to distinguish between the instructive effects of cell-cell versus cell-ECM interactions, as well as constellations of signaling molecules; and these were used in conjunction with physiologically relevant 3 dimensional human breast cultures. Both immortalized and primary human breast progenitors were analyzed. We report on the functional ability of those proteins of the mammary gland that maintain quiescence, maintain the progenitor state, and guide progenitor differentiation towards myoepithelial and luminal lineages.

  13. Method for quantifying the fate of petroleum in the environment

    International Nuclear Information System (INIS)

    Mills, M.A.; McDonald, T.J.; Bonner, J.S.; Simon, M.A.; Autenrieth, R.L.

    1999-01-01

    Petroleum is a complex mixture of a wide range of hydrocarbon and non-hydrocarbon compounds of various physical and chemical properties. In recent years, the research on the fate of petroleum in the environment has required analytical methods that can provide more detailed information on the components of petroleum than traditional standard methods. The analytical method presented for aqueous, sediment, and soil samples provides several levels of information on petroleum in the environment. The Total Extractable Materials (TEM) analysis provides a gross measure of petroleum in the environment using methylene chloride extraction and gravimetric analysis. Gross composition analysis separates the methylene chloride extract into a saturate hydrocarbon, an aromatic hydrocarbon, and a polar fraction each measured gravimetrically. In contrast, the target compound analysis provides a detailed measure by GC-MS of 62 specific compounds. Normalization to the conservative compound, 17α, 21β-(H)Hopane, is incorporated into the method to reduce the effects of sample and site heterogeneity. Quality control and quality assurance procedures are integral parts of these analyses to assure the validity of the resulting data. (author)

  14. Niche as a determinant of word fate in online groups.

    Directory of Open Access Journals (Sweden)

    Eduardo G Altmann

    2011-05-01

    Full Text Available Patterns of word use both reflect and influence a myriad of human activities and interactions. Like other entities that are reproduced and evolve, words rise or decline depending upon a complex interplay between their intrinsic properties and the environments in which they function. Using Internet discussion communities as model systems, we define the concept of a word niche as the relationship between the word and the characteristic features of the environments in which it is used. We develop a method to quantify two important aspects of the size of the word niche: the range of individuals using the word and the range of topics it is used to discuss. Controlling for word frequency, we show that these aspects of the word niche are strong determinants of changes in word frequency. Previous studies have already indicated that word frequency itself is a correlate of word success at historical time scales. Our analysis of changes in word frequencies over time reveals that the relative sizes of word niches are far more important than word frequencies in the dynamics of the entire vocabulary at shorter time scales, as the language adapts to new concepts and social groupings. We also distinguish endogenous versus exogenous factors as additional contributors to the fates of words, and demonstrate the force of this distinction in the rise of novel words. Our results indicate that short-term nonstationarity in word statistics is strongly driven by individual proclivities, including inclinations to provide novel information and to project a distinctive social identity.

  15. Metabolic fate of fenetylline in rat and man.

    Science.gov (United States)

    Yoshimura, H; Yoshimitsu, T; Yamada, H; Koga, N; Oguri, K

    1988-08-01

    1. Metabolic fate of 7-[2-(alpha-methylphenylethylamino)ethyl]theophylline hydrochloride (fenetylline) was investigated in male Sprague-Dawley rats and three male volunteers. 2. Six metabolites were identified in the rat urine as amphetamine(AP), p-hydroxy-AP, acetylaminoethyl-theophylline(TP), aminoethyl-TP, hydroxyethyl-TP and carboxymethyl-TP by comparison of their spectral properties and h.p.l.c. and g.l.c. characteristics with those of authentic samples. All these metabolites was also detected in the urine of humans receiving fenetylline. 3. Quantification of these metabolites using h.p.l.c. and g.l.c. showed that carboxymethyl-TP, p-hydroxy-AP and acetylaminoethyl-TP were the major metabolites in 0-24 h rat urine at 13.7%, 11.2% and 9.3% of dose, respectively. In men, carboxymethyl-TP(39-43% dose) and AP(23-33% dose) were the major metabolites in 0-48 h urine. 4. These results suggest that fenetylline metabolism proceeds via oxidative cleavage at two different sites to produce aminoethyl-TP and AP, respectively. The pathway producing AP predominates, in both man and rat, but is more predominant in the former.

  16. Nanomaterials for regulating cancer and stem cell fate

    Science.gov (United States)

    Shah, Birju P.

    The realm of nanomedicine has grown exponentially over the past few decades. However, there are several obstacles that need to be overcome, prior to the wide-spread clinical applications of these nanoparticles, such as (i) developing well-defined nanoparticles of varying size, morphology and composition to enable various clinical applications; (ii) overcome various physiological barriers encountered in order to deliver the therapeutics to the target location; and (iii) real-time monitoring of the nano-therapeutics within the human body for tracking their uptake, localization and effect. Hence, this dissertation focuses on developing multimodal nanotechnology-based approaches to overcome the above-mentioned challenges and thus enable regulation of cancer and stem cell fate. The initial part of this dissertation describes the development of multimodal magnetic core-shell nanoparticles (MCNPs), comprised of a highly magnetic core surrounded by a thin gold shell, thus combining magnetic and plasmonic properties. These nanoparticles were utilized for mainly two applications: (i) Magnetically-facilitated delivery of siRNA and plasmid DNA for effective stem cell differentiation and imaging and (ii) Combined hyperthermia and targeted delivery of a mitochondria-targeting peptide for enhancing apoptosis in cancer cells. The following part of this dissertation presents the generation of a multi-functional cyclodextrin-conjugated polymeric delivery platform (known as DexAMs), for co-delivery of anticancer drugs and siRNAs in a target-specific manner to brain tumor cells. This combined delivery of chemotherapeutics and siRNA resulted in a synergistic effect on the apoptosis of brain tumor cells, as compared to the individual treatments. The final part of this thesis presents development of stimuli-responsive uorescence resonance energy transfer (FRET)-based mesoporous silica nanoparticles for real-time monitoring of drug release in cells. The stimuli-responsive behavior of

  17. Quantifying and modelling the effects of environmental factors on wood properties of Eucalyptus grandis in South Africa

    CSIR Research Space (South Africa)

    Naidoo, Sasha

    2011-03-01

    Full Text Available screening techniques. Furthermore, because this species lacks distinct annual boundaries that correspond to seasonal climatic changes, the change in wood properties with age usually cannot be studied with reasonable accuracy. For this reason, a study...

  18. Fate of pesticides in field ditches: the TOXSWA simulation model

    NARCIS (Netherlands)

    Adriaanse, P.I.

    1996-01-01

    The TOXSWA model describes the fate of pesticides entering field ditches by spray drift, atmospheric deposition, surface run-off, drainage or leaching. It considers four processes: transport, transformation, sorption and volatilization. Analytical andnumerical solutions corresponded well. A sample

  19. Evaluating the fate of organic compounds in the Cameroon ...

    African Journals Online (AJOL)

    ISHIOMA

    A level III fugacity model was developed to evaluate the fate of chemicals in the Cameroon ... environment, quantify intermedia transfer processes and the major loss ... perform baseline exposure and risk assessment of chemicals used in ...

  20. Aquatic pathways model to predict the fate of phenolic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Aaberg, R.L.; Peloquin, R.A.; Strenge, D.L.; Mellinger, P.J.

    1983-04-01

    Organic materials released from energy-related activities could affect human health and the environment. To better assess possible impacts, we developed a model to predict the fate of spills or discharges of pollutants into flowing or static bodies of fresh water. A computer code, Aquatic Pathways Model (APM), was written to implement the model. The computer programs use compartmental analysis to simulate aquatic ecosystems. The APM estimates the concentrations of chemicals in fish tissue, water and sediment, and is therefore useful for assessing exposure to humans through aquatic pathways. The APM will consider any aquatic pathway for which the user has transport data. Additionally, APM will estimate transport rates from physical and chemical properties of chemicals between several key compartments. The major pathways considered are biodegradation, fish and sediment uptake, photolysis, and evaporation. The model has been implemented with parameters for distribution of phenols, an important class of compounds found in the water-soluble fractions of coal liquids. Current modeling efforts show that, in comparison with many pesticides and polyaromatic hydrocarbons (PAH), the lighter phenolics (the cresols) are not persistent in the environment. The properties of heavier molecular weight phenolics (indanols, naphthols) are not well enough understood at this time to make similar judgements. For the twelve phenolics studied, biodegradation appears to be the major pathway for elimination from aquatic environments. A pond system simulation (using APM) of a spill of solvent refined coal (SRC-II) materials indicates that phenol, cresols, and other single cyclic phenolics are degraded to 16 to 25 percent of their original concentrations within 30 hours. Adsorption of these compounds into sediments and accumulation by fish was minor.

  1. The effect of the indoor environment on the fate of organic chemicals in the urban landscape

    Energy Technology Data Exchange (ETDEWEB)

    Cousins, Anna Palm, E-mail: anna.cousins@ivl.se

    2012-11-01

    To assess the effect of the indoor environment on the urban fate of organic chemicals, an 8-compartment indoor-inclusive steady state multimedia chemical fate model was developed. The model includes typical urban compartments (air, soil, water, sediment, and urban film) and a novel module representing a generic indoor environment. The model was parameterized to the municipality of Stockholm, Sweden and applied to four organic chemicals with different physical-chemical characteristics and use patterns: formaldehyde, 2,4,6-tribromophenol, di-ethylhexylphthalate and decabromodiphenyl ether. The results show that emissions to indoor air may increase the steady state mass and residence time in the urban environment by a factor of 1.1 to 22 for the four chemicals, compared to if emissions are assigned to outdoor air. This is due to the nested nature of the indoor environment, which creates a physical barrier that prevents chemicals from leaving the urban system with outflowing air. For DEHP and BDE 209, the additional partitioning to indoor surfaces results in a greater importance of the indoor removal pathways from surfaces. The outdoor environmental concentrations of these chemicals are predicted to be lower if emitted to indoor air than if emitted to outdoor air because of the additional indoor removal pathways of dust and indoor film, leading to loss of chemical from the system. For formaldehyde and 2,4,6-TBP outdoor environmental concentrations are not affected by whether the release occurs indoors or outdoors because of the limited partitioning to indoor surfaces. A sensitivity analysis revealed that there appears to be a relationship between logK{sub OA} and the impact of the ventilation rate on the urban fate of organic chemicals. -- Highlights: Black-Right-Pointing-Pointer A novel indoor-inclusive multimedia urban fate model is developed and applied. Black-Right-Pointing-Pointer Emissions indoors may increase the urban chemical residence time. Black

  2. The effect of the indoor environment on the fate of organic chemicals in the urban landscape

    International Nuclear Information System (INIS)

    Cousins, Anna Palm

    2012-01-01

    To assess the effect of the indoor environment on the urban fate of organic chemicals, an 8-compartment indoor-inclusive steady state multimedia chemical fate model was developed. The model includes typical urban compartments (air, soil, water, sediment, and urban film) and a novel module representing a generic indoor environment. The model was parameterized to the municipality of Stockholm, Sweden and applied to four organic chemicals with different physical–chemical characteristics and use patterns: formaldehyde, 2,4,6-tribromophenol, di-ethylhexylphthalate and decabromodiphenyl ether. The results show that emissions to indoor air may increase the steady state mass and residence time in the urban environment by a factor of 1.1 to 22 for the four chemicals, compared to if emissions are assigned to outdoor air. This is due to the nested nature of the indoor environment, which creates a physical barrier that prevents chemicals from leaving the urban system with outflowing air. For DEHP and BDE 209, the additional partitioning to indoor surfaces results in a greater importance of the indoor removal pathways from surfaces. The outdoor environmental concentrations of these chemicals are predicted to be lower if emitted to indoor air than if emitted to outdoor air because of the additional indoor removal pathways of dust and indoor film, leading to loss of chemical from the system. For formaldehyde and 2,4,6-TBP outdoor environmental concentrations are not affected by whether the release occurs indoors or outdoors because of the limited partitioning to indoor surfaces. A sensitivity analysis revealed that there appears to be a relationship between logK OA and the impact of the ventilation rate on the urban fate of organic chemicals. -- Highlights: ► A novel indoor-inclusive multimedia urban fate model is developed and applied. ► Emissions indoors may increase the urban chemical residence time. ► Indoor removal from surfaces constitutes an additional loss process

  3. Effect of environmental conditions on the mechanical properties and fungal degradation of polycaprolactone/microcrystalline cellulose/wood flour composites

    Science.gov (United States)

    Ronald Sabo; Liwei Jin; Nicole Stark; Rebecca E. Ibach

    2013-01-01

    Polycaprolactone (PCL) filled with microcrystalline cellulose (MCC), wood flour (WF), or both were characterized before and after exposure to various environmental conditions for 60 days. PCL/WF composites had the greatest tensile strength and modulus compared to neat PCL or PCL composites containing MCC. Electron microscopy indicated better adhesion between WF...

  4. 78 FR 25973 - Final Environmental Impact Statement for the Real Property Master Plan at the Presidio of...

    Science.gov (United States)

    2013-05-03

    ... to improve the learning environment and quality of life at the POM installation. The Final EIS... are also planned to Leadership in Energy and Environmental Design standards to conserve resources. The... the Chamberlain Library on the OMC. An electronic version of the Final EIS can be viewed or downloaded...

  5. Investigating undergraduate students’ ideas about the fate of the Universe

    Directory of Open Access Journals (Sweden)

    Mallory Conlon

    2017-11-01

    Full Text Available As astronomers further develop an understanding of the fate of the Universe, it is essential to study students’ ideas on the fate of the Universe so that instructors can communicate the field’s current status more effectively. In this study, we examine undergraduate students’ preinstruction ideas of the fate of the Universe in ten semester-long introductory astronomy course sections (ASTRO 101 at three institutions. We also examine students’ postinstruction ideas about the fate of the Universe in ASTRO 101 over five semester-long course sections at one institution. The data include precourse surveys given during the first week of instruction (N=264, postinstruction exam questions (N=59, and interviews. We find that, preinstruction, more than a quarter of ASTRO 101 students either do not respond or respond with “I don’t know” when asked what the long-term fate of the Universe is. We also find that, though the term was not necessarily used, students tend to describe a “big chill” scenario in the preinstruction surveys, among a wide variety of other scenarios. A fraction of students describe the fate of smaller-scale systems, possibly due to confusion of the hierarchical nature of structure in the Universe. Preinstruction, students mention the Universe’s expansion when describing how astronomers know the fate of the Universe but do not discuss how we know the Universe is expanding or the relationship between expansion and the fate of the Universe. Postinstruction, students’ responses shift toward greater degrees of completeness and correctness.

  6. The effect of the indoor environment on the fate of organic chemicals in the urban landscape.

    Science.gov (United States)

    Cousins, Anna Palm

    2012-11-01

    To assess the effect of the indoor environment on the urban fate of organic chemicals, an 8-compartment indoor-inclusive steady state multimedia chemical fate model was developed. The model includes typical urban compartments (air, soil, water, sediment, and urban film) and a novel module representing a generic indoor environment. The model was parameterized to the municipality of Stockholm, Sweden and applied to four organic chemicals with different physical-chemical characteristics and use patterns: formaldehyde, 2,4,6-tribromophenol, di-ethylhexylphthalate and decabromodiphenyl ether. The results show that emissions to indoor air may increase the steady state mass and residence time in the urban environment by a factor of 1.1 to 22 for the four chemicals, compared to if emissions are assigned to outdoor air. This is due to the nested nature of the indoor environment, which creates a physical barrier that prevents chemicals from leaving the urban system with outflowing air. For DEHP and BDE 209, the additional partitioning to indoor surfaces results in a greater importance of the indoor removal pathways from surfaces. The outdoor environmental concentrations of these chemicals are predicted to be lower if emitted to indoor air than if emitted to outdoor air because of the additional indoor removal pathways of dust and indoor film, leading to loss of chemical from the system. For formaldehyde and 2,4,6-TBP outdoor environmental concentrations are not affected by whether the release occurs indoors or outdoors because of the limited partitioning to indoor surfaces. A sensitivity analysis revealed that there appears to be a relationship between logK(OA) and the impact of the ventilation rate on the urban fate of organic chemicals. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Data for developing metamodels to assess the fate, transport, and bioaccumulation of organic chemicals in rivers. Chemicals have log Kow ranging from 3 to 14, and rivers have mean annual discharges ranging from 1.09 to 3240 m3/s.

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset was developed to demonstrate how metamodels of high resolution, process-based models that simulate the fate, transport, and bioaccumulation of organic...

  8. Mechanical Properties and Real-Time Damage Evaluations of Environmental Barrier Coated SiC/SiC CMCs Subjected to Tensile Loading Under Thermal Gradients

    Science.gov (United States)

    Appleby, Matthew; Zhu, Dongming; Morscher, Gregory

    2015-01-01

    SiC/SiC ceramic matrix composites (CMCs) require new state-of-the art environmental barrier coatings (EBCs) to withstand increased temperature requirements and high velocity combustion corrosive combustion gasses. The present work compares the response of coated and uncoated SiC/SiC CMC substrates subjected to simulated engine environments followed by high temperature mechanical testing to asses retained properties and damage mechanisms. Our focus is to explore the capabilities of electrical resistance (ER) measurements as an NDE technique for testing of retained properties under combined high heat-flux and mechanical loading conditions. Furthermore, Acoustic Emission (AE) measurements and Digital Image Correlation (DIC) were performed to determine material damage onset and accumulation.

  9. An illusion of control modulates the reluctance to tempt fate

    Directory of Open Access Journals (Sweden)

    Chloe L. Swirsky

    2011-10-01

    Full Text Available The tempting fate effect is that the probability of a fateful outcome is deemed higher following an action that ``tempts'' the outcome than in the absence of such an action. In this paper we evaluate the hypothesis that the effect is due to an illusion of control induced by a causal framing of the situation. Causal frames require that the action make a difference to an outcome and that the action precedes the outcome. If an illusion of control modulates the reluctance to tempt fate, then actions that make a difference to well-being and that occur prior to the outcome should tempt fate most strongly. In Experiments 1--3 we varied whether the action makes a difference and the temporal order of action and outcome. In Experiment 4 we tested whether an action can tempt fate if all outcomes are negative. The results of all four experiments supported our hypothesis that the tempting fate effect depends on a causal construal that gives rise to a false sense of control.

  10. Hematopoietic stem cell fate through metabolic control.

    Science.gov (United States)

    Ito, Kyoko; Ito, Keisuke

    2018-05-25

    Hematopoietic stem cells (HSCs) maintain a quiescent state in the bone marrow to preserve their self-renewal capacity, but also undergo cell divisions as required. Organelles such as the mitochondria sustain cumulative damage during these cell divisions, and this damage may eventually compromise the cells' self-renewal capacity. HSC divisions result in either self-renewal or differentiation, with the balance between the two directly impacting hematopoietic homeostasis; but the heterogeneity of available HSC-enriched fractions, together with the technical challenges of observing HSC behavior, has long hindered the analysis of individual HSCs, and prevented the elucidation of this process. However, recent advances in genetic models, metabolomics analyses and single-cell approaches have revealed the contributions made to HSC self-renewal by metabolic cues, mitochondrial biogenesis, and autophagy/mitophagy, which have highlighted mitochondrial quality as a key control factor in the equilibrium of HSCs. A deeper understanding of precisely how specific modes of metabolism control HSC fate at the single cell level is therefore not only of great biological interest, but will have clear clinical implications for the development of therapies for hematological disease. Copyright © 2018. Published by Elsevier Inc.

  11. Metabolic fate of cinmethylin in goat

    International Nuclear Information System (INIS)

    Woodward, M.D.; Stearns, S.M.; Lee, P.W.

    1989-01-01

    The metabolic fate of [phenyl- 14 C]cinmethylin (1), a novel cineole herbicide, in a lactating goat was examined. The test animal was administered four consecutive daily doses equivalent to approximately 100 ppm cinmethylin in the daily diet. The animal was sacrificed 6 h after the last dosing. A rapid and extensive metabolism of cinmethylin was observed. The major route of elimination was via urine: 40% of the administered dose and feces (20%). [ 14 C]Carbon dioxide or radioactive material in the respired air and residual radioactivity in the digestive tract were not monitored. A complex degradation pattern in the excreta and liver tissue was observed. In addition to the undegraded cinmethylin, recovered only in the feces, at least 25 metabolites were isolated and identified as both organic-extractable and conjugated products. They were classified as mono-, di-, trihydroxylated, dehydrated, carboxylated, methoxylated, and ether linkage cleavage products. The level of 14 C residues in the milk and tissues was low and combined to account for less than 1% of the administered radioactivity

  12. Observations on the Chinese idea of fate

    Directory of Open Access Journals (Sweden)

    Gunnar Sjöholm

    1967-02-01

    Full Text Available Throughout the history of Chinese religion, ideas of fate are present. The earliest forms of Chinese writing occur on thousands of tortoise shells found 65 years ago in the province of Honan. At that time inscriptions on bronze vessels from the first millennium B.C. were already known. But the new material was more difficult to interpret. The amount of material has grown since then: there are now about 100 000 inscribed shells and bones, some hundreds of whole tortoise shields with inscriptions as well as other archaeological material. One third of the signs has been deciphered. The inscriptions are mostly quite brief and contain oracle formulas. The people of the Shang-Yin dynasty (1500-1028 B.C. knew the useful and the beautiful. What did the oracle stand for? Did it represent something necessary? An oracular technique had been developed, "which consisted in touching shells or bones on one side with a little red-hot rod and interpreting according to certain patterns the cracks that arose on the other side as the answers of the ancestral spirits to the questions of the kings. After the consultation of the oracle the questions and often the answers were inscribed beside the cracks. Often also pure memoranda concerning weather, war expeditions etc. were inscribed.

  13. The fate of the earth. 5. ed.

    International Nuclear Information System (INIS)

    Schell, J.

    1982-01-01

    As a result of thorough investigations and based upon the latest findings of scientific research work, this book ''Fate of the Earth'' quite drastically illustrates the manifold and horrible ways mankind and numberless other creatures will have to suffer before perishing in the wake of the pollution of nature and atmosphere for an unforeseeable time, should it happen one day that even only part of the existing nuclear weapons potential of 20.000 megatons of TNT be used at any spot of this world. In view of this global threat, every one of us has to do his bit in trying to safeguard the future of our world. The author discusses all important scientific, political and moral perspectives to be taken into account not only by the superpowers but literally by all states and all people in the face of a possible nuclear holocaust. Presenting his doubts whether the concept of deterrence will in future suffice to prevent a third world war, he implores us, the inhabitants of this planet, to wake up and act before it will be too late. (orig./HSCH) [de

  14. Redox regulation of plant stem cell fate.

    Science.gov (United States)

    Zeng, Jian; Dong, Zhicheng; Wu, Haijun; Tian, Zhaoxia; Zhao, Zhong

    2017-10-02

    Despite the importance of stem cells in plant and animal development, the common mechanisms of stem cell maintenance in both systems have remained elusive. Recently, the importance of hydrogen peroxide (H 2 O 2 ) signaling in priming stem cell differentiation has been extensively studied in animals. Here, we show that different forms of reactive oxygen species (ROS) have antagonistic roles in plant stem cell regulation, which were established by distinct spatiotemporal patterns of ROS-metabolizing enzymes. The superoxide anion (O2·-) is markedly enriched in stem cells to activate WUSCHEL and maintain stemness, whereas H 2 O 2 is more abundant in the differentiating peripheral zone to promote stem cell differentiation. Moreover, H 2 O 2 negatively regulates O2·- biosynthesis in stem cells, and increasing H 2 O 2 levels or scavenging O2·- leads to the termination of stem cells. Our results provide a mechanistic framework for ROS-mediated control of plant stem cell fate and demonstrate that the balance between O2·- and H 2 O 2 is key to stem cell maintenance and differentiation. © 2017 The Authors.

  15. Using gridded multimedia model to simulate spatial fate of Benzo[α]pyrene on regional scale.

    Science.gov (United States)

    Liu, Shijie; Lu, Yonglong; Wang, Tieyu; Xie, Shuangwei; Jones, Kevin C; Sweetman, Andrew J

    2014-02-01

    Predicting the environmental multimedia fate is an essential step in the process of assessing the human exposure and health impacts of chemicals released into the environment. Multimedia fate models have been widely applied to calculate the fate and distribution of chemicals in the environment, which can serve as input to a human exposure model. In this study, a grid based multimedia fugacity model at regional scale was developed together with a case study modeling the fate and transfer of Benzo[α]pyrene (BaP) in Bohai coastal region, China. Based on the estimated emission and in-site survey in 2008, the BaP concentrations in air, vegetation, soil, fresh water, fresh water sediment and coastal water as well as the transfer fluxes were derived under the steady-state assumption. The model results were validated through comparison between the measured and modeled concentrations of BaP. The model results indicated that the predicted concentrations of BaP in air, fresh water, soil and sediment generally agreed with field observations. Model predictions suggest that soil was the dominant sink of BaP in terrestrial systems. Flow from air to soil, vegetation and costal water were three major pathways of BaP inter-media transport processes. Most of the BaP entering the sea was transferred by air flow, which was also the crucial driving force in the spatial distribution processes of BaP. The Yellow River, Liaohe River and Daliao River played an important role in the spatial transformation processes of BaP. Compared with advection outflow, degradation was more important in removal processes of BaP. Sensitivities of the model estimates to input parameters were tested. The result showed that emission rates, compartment dimensions, transport velocity and degradation rates of BaP were the most influential parameters for the model output. Monte Carlo simulation was carried out to determine parameter uncertainty, from which the coefficients of variation for the estimated Ba

  16. Environmental risk assessment of selected organic chemicals based on TOC test and QSAR estimation models.

    Science.gov (United States)

    Chi, Yulang; Zhang, Huanteng; Huang, Qiansheng; Lin, Yi; Ye, Guozhu; Zhu, Huimin; Dong, Sijun

    2018-02-01

    Environmental risks of organic chemicals have been greatly determined by their persistence, bioaccumulation, and toxicity (PBT) and physicochemical properties. Major regulations in different countries and regions identify chemicals according to their bioconcentration factor (BCF) and octanol-water partition coefficient (Kow), which frequently displays a substantial correlation with the sediment sorption coefficient (Koc). Half-life or degradability is crucial for the persistence evaluation of chemicals. Quantitative structure activity relationship (QSAR) estimation models are indispensable for predicting environmental fate and health effects in the absence of field- or laboratory-based data. In this study, 39 chemicals of high concern were chosen for half-life testing based on total organic carbon (TOC) degradation, and two widely accepted and highly used QSAR estimation models (i.e., EPI Suite and PBT Profiler) were adopted for environmental risk evaluation. The experimental results and estimated data, as well as the two model-based results were compared, based on the water solubility, Kow, Koc, BCF and half-life. Environmental risk assessment of the selected compounds was achieved by combining experimental data and estimation models. It was concluded that both EPI Suite and PBT Profiler were fairly accurate in measuring the physicochemical properties and degradation half-lives for water, soil, and sediment. However, the half-lives between the experimental and the estimated results were still not absolutely consistent. This suggests deficiencies of the prediction models in some ways, and the necessity to combine the experimental data and predicted results for the evaluation of environmental fate and risks of pollutants. Copyright © 2016. Published by Elsevier B.V.

  17. Influence of Homogenization and Thermal Processing on the Gastrointestinal Fate of Bovine Milk Fat: In Vitro Digestion Study.

    Science.gov (United States)

    Liang, Li; Qi, Ce; Wang, Xingguo; Jin, Qingzhe; McClements, David Julian

    2017-12-20

    Dairy lipids are an important source of energy and nutrients for infants and adults. The dimensions, aggregation state, and interfacial properties of fat globules in raw milk are changed by dairy processing operations, such as homogenization and thermal processing. These changes influence the behavior of fat globules within the human gastrointestinal tract (GIT). The gastrointestinal fate of raw milk, homogenized milk, high temperature short time (HTST) pasteurized milk, and ultrahigh temperature (UHT) pasteurized milk samples was therefore determined using a simulated GIT. The properties of particles in different regions of the GIT depended on the degree of milk processing. Homogenization increased the initial lipid digestion rate but did not influence the final digestion extent. Thermal processing of homogenized milk decreased the initial rate and final extent of lipid digestion, which was attributed to changes in interfacial structure. These results provide insights into the impact of dairy processing on the gastrointestinal fate of milk fat.

  18. Effects of fertilizers, fungicides and herbicides on the fate of 14C-parathion and 14C-fonofos in soils and crops

    International Nuclear Information System (INIS)

    Lichtenstein, E.P.; Ferris, I.; Liang, T.T.; Koeppe, M.

    1983-01-01

    The fate of 14 C-parathion and 14 C-fonofos in soil is significantly affected by the presence of organic and inorganic fertilizers, fungicides and herbicides, possibly via the effect of soil microflora. Soil microorganisms are responsible for the oxidative as well as the reductive degradation of the insecticide. Using 14 carbon, the authors studied the effects of selected fungicides (benlate, captafol and manzate) herbicides (2,4-D parathion) and fertilizers ((NH 4 ) 6 SO 4 , KNO 3 , urea) on pesticides in Cromberry soils. Results of the study stress the importance of investigating the environmental fate of a particular pesticide in relation to the presence of the agricultural chemicals

  19. Organics in environmental ices: sources, chemistry, and impacts

    Directory of Open Access Journals (Sweden)

    V. F. McNeill

    2012-10-01

    Full Text Available The physical, chemical, and biological processes involving organics in ice in the environment impact a number of atmospheric and biogeochemical cycles. Organic material in snow or ice may be biological in origin, deposited from aerosols or atmospheric gases, or formed chemically in situ. In this manuscript, we review the current state of knowledge regarding the sources, properties, and chemistry of organic materials in environmental ices. Several outstanding questions remain to be resolved and fundamental data gathered before an accurate model of transformations and transport of organic species in the cryosphere will be possible. For example, more information is needed regarding the quantitative impacts of chemical and biological processes, ice morphology, and snow formation on the fate of organic material in cold regions. Interdisciplinary work at the interfaces of chemistry, physics and biology is needed in order to fully characterize the nature and evolution of organics in the cryosphere and predict the effects of climate change on the Earth's carbon cycle.

  20. Polyfluoroalkyl compounds in the aquatic environment: a review of their occurrence and fate.

    Science.gov (United States)

    Ahrens, Lutz

    2011-01-01

    The occurrence and fate of polyfluoroalkyl compounds (PFCs) in the aquatic environment has been recognized as one of the emerging issues in environmental chemistry. PFCs comprise a diverse group of chemicals that are widely used as processing additives during fluoropolymer production and as surfactants in consumer applications for over 50 years. PFCs are known to be persistent, bioaccumulative and have possible adverse effects on humans and wildlife. As a result, perfluorooctane sulfonate (PFOS) has been added to the persistent organic pollutants (POPs) list of the Stockholm Convention in May 2009. However, their homologues, neutral precursor compounds and new PFCs classes continue to be produced. In general, several PFCs from different classes have been detected ubiquitously in the aqueous environment while the concentrations usually range between pg and ng per litre for individual compounds. Sources of PFCs into the aqueous environment are both point sources (e.g., wastewater treatment plant effluents) and nonpoint sources (e.g., surface runoff). The detected congener composition in environmental samples depends on their physicochemical characteristics and may provide information to their sources and transport pathways. However, the dominant transport pathways of individual PFCs to remote regions have not been conclusively characterised to date. The objective of this article is to give an overview on existing knowledge of the occurrence, fate and processes of PFCs in the aquatic environment. Finally, this article identifies knowledge gaps, presents conclusions and recommendations for future work.

  1. Fate, behaviour and weathering of priority HNS in the marine environment: An online tool

    International Nuclear Information System (INIS)

    Cunha, Isabel; Oliveira, Helena; Neuparth, Teresa; Torres, Tiago; Santos, Miguel Machado

    2016-01-01

    Literature data and data obtained with modelling tools were compiled to derive the physicochemical behaviour of 24 priority Hazardous and Noxious Substances (HNS), as a proxy to improve environmental, public health and political issues in relation to HNS spills. Parameters that rule the HNS behaviour in water and those that determine their distribution and persistence in the environment, such as fugacity, physicochemical degradation, biodegradation, bioaccumulation/biotransformation and aquatic toxicity, were selected. Data systematized and produced in the frame of the Arcopol Platform project was made available through a public database ( (http://www.ciimar.up.pt/hns/substances.php)). This tool is expected to assist stakeholders involved in HNS spills preparedness and response, policy makers and legislators, as well as to contribute to a current picture of the scientific knowledge on the fate, behaviour, weathering and toxicity of priority HNS, being essential to support future improvements in maritime safety and coastal pollution response before, during and after spill incidents. - Highlights: • Fate, behaviour and weathering of priority HNS in marine environments are addressed. • Environmental and public health issues in relation to HNS spills are discussed. • Physicochemical behaviour is derived through mathematical tools and literature data. • Data produced are made available through a public online database. • Database can assist relevant bodies involved in HNS spills preparedness and response.

  2. Ecological fate and effects of solvent-refined-coal (SRC) materials: a status report

    Energy Technology Data Exchange (ETDEWEB)

    Strand, J.A. III; Vaughan, B.E. (eds.)

    1981-10-01

    Non-occupational health effects associated with SRC operation will be determined by environmental factors governing the form, transport, and persistence of SRC materials and wastes - factors which also mediate exposure to man. Accordingly, the research described is an attempt to determine the fate of disposed solid wastes and spilled SRC materials, and it necessarily focuses on water soluble, persistent materials with greatest potential for mobility and incorporation into water and food supplies. Initially, aqueous equilibrations of SRC-II liquid material and SRC-I nongasified mineral residue were subjected to chemical characterization. Subsequently, laboratory studies were performed on the interaction of aqueous equilibrates of SRC-II liquid and SRC-I non-gasified mineral residue with soil materials isolated suspended sediments, and bottom sediments. These studies were designed to identify effects of specific sorption reactions ion or induced-ion exchange reactions, and toxicity of water soluble, biologically active materials derived from liquid and solid wastes. Results of these experiments have applicability to the environmental fate and effects of biologically active compounds released under different scenarios from product spills and solid waste disposal.

  3. Individual fates of mesenchymal stem cells in vitro

    Directory of Open Access Journals (Sweden)

    Drasdo Dirk

    2010-05-01

    Full Text Available Abstract Background In vitro cultivated stem cell populations are in general heterogeneous with respect to their expression of differentiation markers. In hematopoietic progenitor populations, this heterogeneity has been shown to regenerate within days from isolated subpopulations defined by high or low marker expression. This kind of plasticity has been suggested to be a fundamental feature of mesenchymal stem cells (MSCs as well. Here, we study MSC plasticity on the level of individual cells applying a multi-scale computer model that is based on the concept of noise-driven stem cell differentiation. Results By simulation studies, we provide detailed insight into the kinetics of MSC organisation. Monitoring the fates of individual cells in high and low oxygen culture, we calculated the average transition times of individual cells into stem cell and differentiated states. We predict that at low oxygen the heterogeneity of a MSC population with respect to differentiation regenerates from any selected subpopulation in about two days. At high oxygen, regeneration becomes substantially slowed down. Simulation results on the composition of the functional stem cell pool of MSC populations suggest that most of the cells that constitute this pool originate from more differentiated cells. Conclusions Individual cell-based models are well-suited to provide quantitative predictions on essential features of the spatio-temporal organisation of MSC in vitro. Our predictions on MSC plasticity and its dependence on the environment motivate a number of in vitro experiments for validation. They may contribute to a better understanding of MSC organisation in vitro, including features of clonal expansion, environmental adaptation and stem cell ageing.

  4. Fate of the antiretroviral drug tenofovir in agricultural soil

    Energy Technology Data Exchange (ETDEWEB)

    Al-Rajab, Abdul Jabbar; Sabourin, Lyne; Chapman, Ralph; Lapen, David R.; Topp, Edward, E-mail: ed.topp@agr.gc.ca [Agriculture and Agri-Food Canada, London, ON, N5V 4T3 (Canada)

    2010-10-15

    Tenofovir (9-(R)-(2-phosphonylmethoxypropyl)-adenine) is an antiretroviral drug widely used for the treatment of human immunodeficiency virus (HIV-1) and Hepatitis B virus (HBV) infections. Tenofovir is extensively and rapidly excreted unchanged in the urine. In the expectation that tenofovir could potentially reach agricultural lands through the application of municipal biosolids or wastewater, and in the absence of any environmental fate data, we evaluated its persistence in selected agricultural soils. Less than 10% of [adenine-8-{sup 14}C]-tenofovir added to soils varying widely in texture (sand, loam, clay loam) was mineralized in a 2-month incubation under laboratory conditions. Tenofovir was less readily extractable from clay soils than from a loam or a sandy loam soil. Radioactive residues of tenofovir were removed from the soil extractable fraction with DT{sub 50}s ranging from 24 {+-} 2 to 67 + 22 days (first order kinetic model) or 44 + 9 to 127 + 55 days (zero order model). No extractable transformation products were detectable by HPLC. Tenofovir mineralization in the loam soil increased with temperature (range 4 {sup o}C to 30 {sup o}C), and did not occur in autoclaved soil, suggesting a microbial basis. Mineralization rates increased with soil moisture content, ranging from air-dried to saturated. In summary, tenofovir was relatively persistent in soils, there were no extractable transformation products detected, and the response of [adenine-8-{sup 14}C]-tenofovir mineralization to soil temperature and heat sterilization indicated that the molecule was biodegraded by aerobic microorganisms. Sorption isotherms with dewatered biosolids suggested that tenofovir residues could potentially partition into the particulate fraction during sewage treatment.

  5. Intrinsic and environmental effects on the interference properties of a high-performance quantum dot single-photon source

    DEFF Research Database (Denmark)

    Gerhardt, Stefan; Iles-Smith, Jake; McCutcheon, Dara

    2018-01-01

    We report a joint experimental and theoretical study of the interference properties of a single-photon source based on a In(Ga)As quantum dot embedded in a quasiplanar GaAs microcavity. Using resonant laser excitation with a pulse separation of 2 ns, we find near-perfect interference of the emitt...... in excitonic Rabi oscillations....

  6. Measurement Properties of Psychosocial and Environmental Measures Associated with Fruit and Vegetable Intake among Middle School Adolescents

    Science.gov (United States)

    Granner, Michelle L.; Evans, Alexandra E.

    2012-01-01

    Objective: To assess the measurement properties of several scales modified or created to assess factors related to fruit and vegetable intake within a young adolescent population. Design: Cross-sectional with data collected via self-report. Setting: Data were collected in regularly scheduled classes in the school setting. Participants: African…

  7. Task 23 - background report on subsurface environmental issues relating to natural gas sweetening and dehydration operations. Topical report, February 1, 1994--February 28, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, J.A.

    1998-12-31

    This report describes information pertaining to environmental issues, toxicity, environmental transport, and fate of alkanolamines and glycols associated with natural gas sweetening and dehydration operations. Waste management associated with the operations is also discussed.

  8. The Fate of Unstable Circumbinary Planets

    Science.gov (United States)

    Kohler, Susanna

    2016-03-01

    What happens to Tattooine-like planets that are instead in unstable orbits around their binary star system? A new study examines whether such planets will crash into a host star, get ejected from the system, or become captured into orbit around one of their hosts.Orbit Around a DuoAt this point we have unambiguously detected multiple circumbinary planets, raising questions about these planets formation and evolution. Current models suggest that it is unlikely that circumbinary planets would be able to form in the perturbed environment close their host stars. Instead, its thought that the planets formed at a distance and then migrated inwards.One danger such planets face when migrating is encountering ranges of radii where their orbits become unstable. Two scientists at the University of Chicago, Adam Sutherland and Daniel Fabrycky, have studied what happens when circumbinary planets migrate into such a region and develop unstable orbits.Producing Rogue PlanetsTime for planets to either be ejected or collide with one of the two stars, as a function of the planets starting distance (in AU) from the binary barycenter. Colors represent different planetary eccentricities. [Sutherland Fabrycky 2016]Sutherland and Fabrycky used N-body simulations to determine the fates of planets orbiting around a star system consisting of two stars a primary like our Sun and a secondary roughly a tenth of its size that are separated by 1 AU.The authors find that the most common fate for a circumbinary planet with an unstable orbit is ejection from the system; over 80% of unstable planets were ejected. This has interesting implications: if the formation of circumbinary planets is common, this mechanism could be filling the Milky Way with a population of free-floating, rogue planets that no longer are associated with their host star.The next most common outcome for unstable planets is collision with one of their host stars (most often the secondary), resulting inaccretion of the planet

  9. Estuarine Human Activities Modulate the Fate of Changjiang-derived Materials in Adjacent Seas

    Science.gov (United States)

    WU, H.

    2017-12-01

    Mega constructions have been built in many river estuaries, but their environmental consequences in the adjacent coastal oceans were often overlooked. This issue was addressed with an example of the Changjiang River Estuary, which was recently built with massive navigation and reclamation constructions in recent years. Based on the model validations against cruises data and the numerical scenario experiments, it is shown that the estuarine constructions profoundly affected the fates of riverine materials in an indeed large offshore area. This is because estuarine dynamics are highly sensitive to their bathymetries. Previously, the Three Gorges Dam (TGD) was thought to be responsible for some offshore environmental changes through modulating the river plume extension, but here we show that its influences are secondary. Since the TGD and the mega estuarine constructions were built during the similar period, their influences might be confused.

  10. National, holistic, watershed-scale approach to understand the sources, transport, and fate of agricultural chemicals

    Science.gov (United States)

    Capel, P.D.; McCarthy, K.A.; Barbash, J.E.

    2008-01-01

    This paper is an introduction to the following series of papers that report on in-depth investigations that have been conducted at five agricultural study areas across the United States in order to gain insights into how environmental processes and agricultural practices interact to determine the transport and fate of agricultural chemicals in the environment. These are the first study areas in an ongoing national study. The study areas were selected, based on the combination of cropping patterns and hydrologic setting, as representative of nationally important agricultural settings to form a basis for extrapolation to unstudied areas. The holistic, watershed-scale study design that involves multiple environmental compartments and that employs both field observations and simulation modeling is presented. This paper introduces the overall study design and presents an overview of the hydrology of the five study areas. Copyright ?? 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

  11. SimpleTreat: a spreadsheet-based box model to predict the fate of xenobiotics in a municipal waste water treatment plant

    NARCIS (Netherlands)

    Struijs J; van de Meent D; Stoltenkamp J

    1991-01-01

    A non-equilibrium steady state box model is reported, that predicts the fate of new chemicals in a conventional sewage treatment plant from a minimal input data set. The model, written in an electronic spreadsheet (Lotus TM 123), requires a minimum input: some basic properties of the chemical, its

  12. Implementation of the Leaching Environmental Assessment Framework

    Science.gov (United States)

    New leaching tests are available in the U.S. for developing more accurate source terms for use in fate and transport models. For beneficial use or disposal, the use of the leaching environmental assessment framework (LEAF) will provide leaching results that reflect field condit...

  13. Environmental impact of coal utilization (from raw material to waste resources): Proceedings

    International Nuclear Information System (INIS)

    Sahu, K.C.

    1991-10-01

    The proceedings contains 27 papers presented at the conference on environmental impact of coal utilization from raw material to waste resources which was held at the Indian Institute of Technology, Bombay, during 14-15 January 1991. The conference was held as a follow-up of the research project to study the impact of coal utilization. The project was undertaken jointly by the Indian Institute of Technology, Bombay and the University of Western Ontario, Canada. The project was funded by the International Development Research Centre, Ottawa (Canada). The principle themes of the conference were : occurrence of trace elements in coal, fate of trace elements during combustion of coal, characterisation of fly ash and its properties and utilization, and environmental impact of ash disposal. (M.G.B.)

  14. The sources, fate, and toxicity of chemical warfare agent degradation products.

    Science.gov (United States)

    Munro, N B; Talmage, S S; Griffin, G D; Waters, L C; Watson, A P; King, J F; Hauschild, V

    1999-01-01

    We include in this review an assessment of the formation, environmental fate, and mammalian and ecotoxicity of CW agent degradation products relevant to environmental and occupational health. These parent CW agents include several vesicants: sulfur mustards [undistilled sulfur mustard (H), sulfur mustard (HD), and an HD/agent T mixture (HT)]; nitrogen mustards [ethylbis(2-chloroethyl)amine (HN1), methylbis(2-chloroethyl)amine (HN2), tris(2-chloroethyl)amine (HN3)], and Lewisite; four nerve agents (O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX), tabun (GA), sarin (GB), and soman (GD)); and the blood agent cyanogen chloride. The degradation processes considered here include hydrolysis, microbial degradation, oxidation, and photolysis. We also briefly address decontamination but not combustion processes. Because CW agents are generally not considered very persistent, certain degradation products of significant persistence, even those that are not particularly toxic, may indicate previous CW agent presence or that degradation has occurred. Of those products for which there are data on both environmental fate and toxicity, only a few are both environmentally persistent and highly toxic. Major degradation products estimated to be of significant persistence (weeks to years) include thiodiglycol for HD; Lewisite oxide for Lewisite; and ethyl methyl phosphonic acid, methyl phosphonic acid, and possibly S-(2-diisopropylaminoethyl) methylphosphonothioic acid (EA 2192) for VX. Methyl phosphonic acid is also the ultimate hydrolysis product of both GB and GD. The GB product, isopropyl methylphosphonic acid, and a closely related contaminant of GB, diisopropyl methylphosphonate, are also persistent. Of all of these compounds, only Lewisite oxide and EA 2192 possess high mammalian toxicity. Unlike other CW agents, sulfur mustard agents (e.g., HD) are somewhat persistent; therefore, sites or conditions involving potential HD contamination should include an

  15. Transport and fate of engineered silver nanoparticles in aquifer media

    Science.gov (United States)

    Adrian, Y.; Schneidewind, U.; Azzam, R.

    2016-12-01

    Engineered silver nanoparticles (AgNPs) are used in various consumer and medical products due to their antimicrobial properties. Their transport behavior in the environment is still under investigation. Previous studies have been focusing on the transport of AgNPs in test systems with pure quartz sand or top soil materials, but studies investigating aquifer material are rare. However, the protection of groundwater resources is an important part in the protection of human health and the assurance of future economic activities. Therefore, expert knowledge regarding the transport, behavior and fate of engineered nanoparticles as potential contaminants in aquifers is essential. The transport and retention behavior of two commercially available engineered AgNPs (one stabilized with a polymere and one with a surfactant) in natural silicate-dominated aquifer material was investigated in saturated laboratory columns. For the experiments a mean grain size diameter of 0.7 mm was chosen with varying silt and clay contents to investigate their effect on the transport behavior of the AgNPs. Typical flow velocities were chosen to represent natural conditions. Particle concentration in the effluent was measured using ICP-MS and the finite element code HYDRUS-1D was used to model the transport and retention processes. The size of the silver nanoparticles in the effluent was analyzed using Flow Field-Flow Fractionation. The obtained results show that silt and clay contents as well as the stabilization of the AgNPs control the transport and retention of AgNPs. Increasing breakthrough was observed with decreasing clay and silt content.

  16. Environmental audit of the Maywood Site: Formerly Utilized Sites Remedial Action Program, Maywood Interim Storage Site vicinity properties

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-01

    This report presents the results of the Environmental Audit of the Maywood Site managed by the Formerly Utilized Sites Remedial Action Program (FUSRAP). The Audit was carried out from November 7 through 16, 1990. The Audit Team found overall technical competence and knowledge of management and staff to be excellent. This applies to DOE as well as to Bechtel National, Incorporated (BNI). In particular, there was excellent knowledge of federal, state, and local environmental regulations, as well as analysis for applicability of these regulations to FUSRAP. Project management of the Maywood Site is also excellent. BNI and DOE project staff have made frequent contact with members of the community, and all removal actions and remedial investigation activities have been planned, scheduled, and accomplished with competence and attention to total quality principles. To date, all actions taken for the Maywood Site cleanup have been completed ahead of schedule and on or under budget. Weakness noted include self-assessment efforts by DOE, failure to fully implement DOE Order requirements throughout the program, and some discrepancies in formally documenting and reviewing procedures. 7 figs., 10 tabs.

  17. Fate of diuron and linuron in a field lysimeter experiment.

    Science.gov (United States)

    Guzzella, L; Capri, E; Di Corcia, A; Barra Caracciolo, A; Giuliano, G

    2006-01-01

    The environmental fate of herbicides can be studied at different levels: in the lab with disturbed or undisturbed soil columns or in the field with suction cup lysimeters or soil enclosure lysimeters. A field lysimeter experiment with 10 soil enclosures was performed to evaluate the mass balance in different environmental compartments of the phenylurea herbicides diuron [3-(3,4-diclorophenyl)-1,1-dimethyl-urea] and linuron [3-(3,4-dichlorophenyl)-1-methoxy-1-methylurea]. After application on the agricultural soil, the herbicides were searched for in soil, pore water, and air samples. Soil and water samples were collected at different depths of the soil profile and analyzed to determine residual concentrations of both the parent compounds and of their main transformation products, to verify their persistence and their leaching capacity. Air volatilization was calculated using the theoretical profile shape method. The herbicides were detected only in the surface layer (0-10 cm) of soil. In this layer, diuron was reduced to 50% of its initial concentration at the end of the experiment, while linuron was still 70% present after 245 d. The main metabolites detected were DCPMU [3-(3,4-dichlorophenyl)-1-methylurea] and DCA (3,4-dichloroaniline). In soil pore water, diuron and linuron were detected at depths of 20 and 40 cm, although in very low concentrations. Therefore the leaching of these herbicides was quite low in this experiment. Moreover, volatilization losses were inconsequential. The calculated total mass balance showed a high persistence of linuron and diuron in the soil, a low mobility in soil pore water (less than 0.5% in leachate water), and a negligible volatilization effect. The application of the Pesticide Leaching Model (PELMO) showed similar low mobility of the chemicals in soil and water, but overestimated their volatilization and their degradation to the metabolite DCPMU. In conclusion, the use of soil enclosure lysimeters proved to be a good

  18. Does a property-specific environmental health risk create a “neighborhood” housing price stigma? Arsenic in private well water

    Science.gov (United States)

    Boyle, Kevin J.; Kuminoff, Nicolai V.; Zhang, Congwen; Devanney, Michael; Bell, Kathleen P.

    2010-03-01

    This paper examines the impact of arsenic contamination of groundwater on sale prices of residential properties and bare land transactions in two Maine towns, Buxton and Hollis, that rely on private wells to supply their drinking water. Prompted by tests of well water by the state of Maine, media attention focused on the communities in 1993 and 1994 when 14% of private wells were found to have arsenic concentrations exceeding the U.S. Environmental Protection Agency standard of 0.05 mg/L. Households could mitigate the serious health risks associated with arsenic ingestion by purchasing bottled water or by installing a reverse osmosis home treatment system. Our results indicate that the initial arsenic finding in 1993 led to significant, but temporary, 2 year decreases in property prices. This is a much shorter effect on prices than has been observed for Superfund sites, where prices can be depressed for a decade. These results suggest that a property-specific contamination incident that is treatable may not have a long-lasting effect on sale prices, but further research is needed to confirm if the dissipation of the price effect was actually due to the installation of in-home water treatment systems or due to the dissipation of perceived risk once the media coverage stopped.

  19. Assessment of Contaminated Brine Fate and Transport in MB139 at WIPP

    Energy Technology Data Exchange (ETDEWEB)

    Kuhlman, Kristopher L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Applied Systems Analysis and Research Dept.; Malama, Bwalya [Sandia National Lab., Carlsbad, NM (United States). Performance Assessment Dept.

    2014-07-01

    Following the radionuclide release event of February 14, 2014 at the Waste Isolation Pilot Plant (WIPP), actinide contamination has been found on the walls and floor in Panel 7 as a result of a release in Room 7 of Panel 7. It has been proposed to decontaminate Panel 7 at the WIPP by washing contaminated surfaces in the underground with fresh water. A cost-effective cleanup of this contamination would allow for a timely return to waste disposal operations at WIPP. It is expected that the fresh water used to decontaminate Panel 7 will flow as contaminated brine down into the porosity of the materials under the floor – the run-of-mine (ROM) salt above Marker Bed 139 (MB139) and MB139 itself – where its fate will be controlled by the hydraulic and transport properties of MB139. Due to the structural dip of MB139, it is unlikely that this brine would migrate northward towards the Waste-Handling Shaft sump. A few strategically placed shallow small-diameter observation boreholes straddling MB139 would allow for monitoring the flow and fate of this brine after decontamination. Additionally, given that flow through the compacted ROM salt floor and in MB139 would occur under unsaturated (or two-phase) conditions, there is a need to measure the unsaturated flow properties of crushed WIPP salt and salt from the disturbed rock zone (DRZ).

  20. Multi-scale porous materials: from adsorption and poro-mechanics properties to energy and environmental applications

    International Nuclear Information System (INIS)

    Pellenq, Roland J.M.

    2012-01-01

    Document available in extended abstract form only. 'Multi-scale Porous Materials under the Nano-scope'. Setting up the stage, one can list important engineering problems such as hydrogen storage for transportation applications, electric energy storage in batteries, CO 2 sequestration in used coal mines, earthquake mechanisms, durability of nuclear fuels, stability of soils and sediment and cements and concrete cohesive properties in the context of sustainability. With the exception of health, these are basically the challenging engineering problems of the coming century that address energy, environment and natural hazards. Behind all those problems are complex multi-scale porous materials that have a confined fluid in their pore void: water in the case of clays and cement, an electrolyte in the case of batteries and super-capacitors, weakly interacting molecular fluids in the case of hydrogen storage devices, gas-shale and nuclear fuel bars. So what do we mean by 'under the nano-scope'? The nano-scope does not exist as a single experimental technique able of assessing the 3D texture of complex multi-scale material. Obviously techniques such as TEM are part of the answer but are not the 'nano-scope' in itself. In our idea, the 'nano-scope' is more than a technique producing images. It is rather a concept that links a suite of modeling techniques coupled with experiments (electron and X-rays microscopies, tomography, nano-indentation, nano-scratching...). Fig 1 gives an outline of this strategy for cement. It allows accessing material texture, their chemistry, their mechanical behavior, their adsorption/condensation behavior at all scales starting from the nano-scale upwards. The toolbox of the simulation aspect of the 'nano-scope' is akin to a statistical physics description of material texture and properties including the thermodynamics and dynamics of the fluids confined to their pore voids as a means to linking atomic scale properties to macroscopic properties