WorldWideScience

Sample records for aquatic environments biological

  1. Biota and biological principles of the aquatic environment

    International Nuclear Information System (INIS)

    The first of several compilations of briefing papers on water quality prepared by the U.S. Geological Survey is presented. Each briefing paper is prepared in a simple, nontechnical, easy to understand manner. This U.S. Geological Survey Circular contains papers on selected biota and biological principles of the aquatic environment. Briefing papers are included on Why biology in water quality studies , Stream biology, Phytoplankton, Periphyton, Drift organisms in streams, Family Chironomidae (Diptera), Influences of water temperature on aquatic biota, and Stream channelization: Effects on stream fauna

  2. Arsenic in the aquatic environment - speciation and biological effects

    Energy Technology Data Exchange (ETDEWEB)

    Landner, L. [Swedish Environmental Research Group (MFG)

    1998-03-01

    The present report is a contribution to EC Commission`s undertaking to review existing EC provisions on the substances for which Sweden has been granted transitional provisions. The provisions imply that Sweden may maintain more stringent regulations on four substances until the end of 1998. The present report deals with speciation and biological effects of arsenic in three types of aquatic environments - marine water, estuarine or brackish water and freshwater. The similarity between arsenate and phosphate and the interference in phosphorylation reactions is discussed. It is clear that in Scandinavian inland waters the concentration of phosphorous is on average lower than in most inland waters in continental Europe. However, in most inland waters phosphorus is the limiting factor for phytoplankton development and eutrophication, which means that there is a clear risk for detrimental effects in the great majority of inland waters, also eutrophic waters 167 refs, 27 figs, 12 tabs. Exemption Substances Project (Directive 89/677/EEC)

  3. Hazardous wastes in aquatic environments: Biological uptake and metabolism studies

    Energy Technology Data Exchange (ETDEWEB)

    Barber, J.; Apblett, A.; Ensley, H. [and others

    1996-05-02

    The projects discussed in this article include the following: the uptake, accumulation, metabolism, toxicity and physiological effects of various environmentally-important contaminants, inorganic and organic, in several wetland species that are interrelated through food webs; and investigation of the potential for developing and linking chemical and biological methods of remediation so as to encapsulate bioaccummulated ions in stable wasteforms such as ceramics and/or zeolites. 24 refs.

  4. Presence of pesticide residues in water, sediment and biological samples taken from aquatic environments in Honduras

    International Nuclear Information System (INIS)

    The objective of this study was to detect the presence of persistent pesticides in water, sediment and biological samples taken from aquatic environments in Honduras during the period 1995-98. Additionally, the LC50 for 2 fungicides and 2 insecticides on post-larval Penaeus vannamei was determined in static water bioassays. A total of 80 water samples, 16 sediment samples and 7 biological samples (fish muscle tissue) were analyzed for detection of organochlorine and organophosphate pesticide residues. The results of sample analyses indicate a widespread contamination of Honduran continental and coastal waters with organochlorine pesticides. Most detections were of low (50 values and were therefore found to be much more toxic to the post-larval shrimp than the fungicides tridemorph and propiconazole. (author)

  5. Introducing Aquatic Biology

    OpenAIRE

    Kinne, Otto; Browman, Howard I.; Seaman, Matthias

    2007-01-01

    The Inter-Research Science Center (IR) journals Marine Ecology Progress Series (MEPS) and Aquatic Microbial Ecology (AME) have been receiving increasing numbers of high-quality manuscripts that are principally biological, rather than ecological. With regret, we have had to turn these submissions away. Also, leading limnologists have for many years suggested that IR should provide an outlet for top quality articles on freshwater biology and ecology. Aquatic Biology (...

  6. Radioactivity in the Canadian aquatic environment

    International Nuclear Information System (INIS)

    Sources of radionuclides arising from natural anthropogenic processes as well as technologically enhanced natural radiation are discussed. Transport, distribution and behaviour of these radionuclides in aquatic systems are influenced by physical, chemical, biological and geological processes and conditions in freshwater and marine environments. Dosimetry of aquatic organisms, as well as various methods of measuring dose rate are presented. Effects of ionizing radiation (acute and chronic exposure) on aquatic organisms, populations and ecosystems are reviewed. This review covers the entire spectrum of the aquatic environment. Results of many studies are summarized. 300+ refs

  7. Aquatic Environment 2000

    DEFF Research Database (Denmark)

    Svendsen, L. M.; Bijl, L. van der; Boutrup, S.; Iversen, T. M.; Ellermann, T.; Hovmand, M. F.; Bøgestrand, J.; Grant, R.; Hansen, J.; Jensen, J. P.; Stockmarr, J.; Laursen, K. D.

    The report summarizes the results of the Danish Aquatic Monitoring and Assessment Programme 1998-2003. Danish Environmental Protection Agency 2000: NOVA-2003. Programbeskrivelse for det nationale program for overvågning af vandmiljøet 1998-2003. 397 pp. - Redegørelse fra Miljøstyrelsen nr. 1 (in...

  8. Aquatic environment pollution

    OpenAIRE

    Anechitoae Constantin; Grigorut Cornel; Ciortescu Gabriel

    2010-01-01

    From immemorial times people have been concerned with environment protection, certainly on a scale corresponding to the impact of human activities on it, taking into account, from the very beginning, the interest on the health of drinking water sources, where their animals drank and where their respective communities could drink clean water and use it in daily cooking, until nowadays, when the marine environment has turned into an international policy. Taking into account that the natural env...

  9. Tritium in the aquatic environment

    International Nuclear Information System (INIS)

    Tritium is of environmental importance because it is released from nuclear facilities in relatively large quantities and because it has a half life of 12.26 y. Most of the tritium released into the atmosphere eventually reaches the aqueous environment, where it is rapidly taken up by aquatic organisms. This paper reviews the current literature on tritium in the aquatic environment. Conclusions from the review, which covered studies of algae, aquatic macrophytes, invertebrates, fish, and the food chain, were that aquatic organisms incorporate tritium into their tissue-free water very rapidly and reach concentrations near those of the external medium. The rate at which tritium from tritiated water is incorporated into the organic matter of cells is slower than the rate of its incorporation into the tissue-free water. If organisms consume tritiated food, incorporation of tritium into the organic matter is faster, and a higher tritium concentration is reached than when the organisms are exposed to only tritiated water alone. Incorporation of tritium bound to molecules into the organic matter depends on the chemical form of the ''carrier'' molecule. No evidence was found that biomagnification of tritium occurs at higher trophic levels. Radiation doses from tritium releases to large populations of humans will most likely come from the consumption of contaminated water rather than contaminated aquatic food products

  10. Tritium in the aquatic environment

    Energy Technology Data Exchange (ETDEWEB)

    Blaylock, B.G.; Hoffman, F.O.; Frank, M.L.

    1986-02-01

    Tritium is of environmental importance because it is released from nuclear facilities in relatively large quantities and because it has a half life of 12.26 y. Most of the tritium released into the atmosphere eventually reaches the aqueous environment, where it is rapidly taken up by aquatic organisms. This paper reviews the current literature on tritium in the aquatic environment. Conclusions from the review, which covered studies of algae, aquatic macrophytes, invertebrates, fish, and the food chain, were that aquatic organisms incorporate tritium into their tissue-free water very rapidly and reach concentrations near those of the external medium. The rate at which tritium from tritiated water is incorporated into the organic matter of cells is slower than the rate of its incorporation into the tissue-free water. If organisms consume tritiated food, incorporation of tritium into the organic matter is faster, and a higher tritium concentration is reached than when the organisms are exposed to only tritiated water alone. Incorporation of tritium bound to molecules into the organic matter depends on the chemical form of the ''carrier'' molecule. No evidence was found that biomagnification of tritium occurs at higher trophic levels. Radiation doses from tritium releases to large populations of humans will most likely come from the consumption of contaminated water rather than contaminated aquatic food products.

  11. Tritium in the aquatic environment

    International Nuclear Information System (INIS)

    Most of the tritium released from nuclear facilities into the atmosphere eventually reaches the aqueous environment where it is rapidly taken up by aquatic organisms. This paper reviews the current literature on tritium in the aquatic environment. Conclusions from the review, which covered algae, aquatic plants, invertebrates, fish, and food chain studies, were that aquatic organisms incorporate tritium into their tissue free water very rapidly and reach concentrations near that of the external medium. Incorporation of tritium from triated water into the organic matter of cells is at a slower rate than incorporation into the tissue free water. If organisms consume tritiated food, incorporation of tritium into the organic matter is faster and a higher tritium concentration is reached than when the organisms are exposed to only tritiated water. Incorporation of tritium bound to molecules into the organic matter depends on the chemical form of the 'carrier' molecule. No evidence was found that biomagnification of tritium occurs at higher tropic levels. Radiation doses to large populations of humans from tritium releases will most likely be from the consumption of contaminated water rather than contaminated aquatic food products. (author)

  12. Aquatic and Terrestrial Environment 2004

    DEFF Research Database (Denmark)

    Andersen, J. M.; Boutrup, S.; Bijl, L. van der;

    This report presents the 2004 results of the Danish National Monitoring and Assess-ment Programme for the Aquatic and Terrestrial Environments (NOVANA). 2004 was the first year in which terrestrial nature was included in the monitoring pro-gramme. The report reviews the state of the groundwater......, watercourses, lakes and marine waters and the pressures upon them and reviews the monitoring of terrestrial natural habitats and selected plants and animals. The report is based on the annual reports prepared for each subprogramme by the Topic Centres. The latter reports are mainly based on data collected and...

  13. Rubber tire leachates in the aquatic environment.

    Science.gov (United States)

    Evans, J J

    1997-01-01

    Tires have a deleterious effect on the environment. This review discusses the background of scrap tires discarded in the environment, including tire composition, adverse environmental effects, threats to public health and safety, and solid waste management. Despite the widespread use of scrap tires in environmental applications, both land-based and aquatic, data on the indicators of environmental degradation are extremely scarce. Indicators of environmental degradation include analysis of chemicals within the water and sediment, analysis of contaminants within organisms, and analysis of the biological effects of these compounds on plants, animals, microbes, and organelles. Although these indicators are most useful when used in parallel, a review of the available information on chemical characterization of tire leachate from tire storage facilities, manufacturing, usage in recycling applications, and toxicity exposure studies, of vegetation surveys from waste tire areas and reviews of mammalian tire product toxicity, and of toxicity, mutagenicity, and carcinogenicity of tire exposure in experimental aquatic animals, microbes, and organelles is presented. The major characteristics of these studies are discussed in specific sections. The "Discussion and Conclusions" section discusses and summarizes the biological effects and chemical characterization of tire leachates. A global environmental perspective is included to improve our understanding of the deficiency of the current knowledge of tire leachate toxicity from various sources and to encourage interdisciplinary studies to establish the pattern of pollution associated with waste tire management. PMID:9216257

  14. The Experiment Study of the Influence on Plant Seeds and Aquatic Bio-logical Survival in High Altitude Environment

    Institute of Scientific and Technical Information of China (English)

    陈霈润

    2015-01-01

    There is A certain foundation in this experiment. It was the second time we did this experiment. The purposes are three parts, first, explore the 30000~40000 meters high sky with two cameras recording the scene. The Second, find out whether the high sky condition (temperature, air pressure, cosmic ray) make influence on plants seeds. The third, text whether normal aquatic animal is able to survive in high sky. The conclusions are also three parts. It is important to set a deadline for my group member to finish the assignment, and also check their process, or they might delay their own part of work or they are not in charge of the work. As the leader, I should be thoughtful. Not only about members’assignment, but also the details of their work, previously. Discuss about each task with group to ensure the correctness. Last but not least, every part of the experiment needs to be tested carefully. Only if we try our best to prevent accidents that might happen, then the experiment is able to suc⁃cess.

  15. Search for the evidence of endocrine disruption in the aquatic environment: Lessons to be learned from joint biological and chemical monitoring in the European Project COMPREHEND

    NARCIS (Netherlands)

    Eggen, R.I.L.; Bengtsson, B.E.; Bowmer, C.T.; Gerritsen, A.A.M.; Gibert, M.; Hylland, K.; Johnson, A.C.; Leonards, P.E.G.; Nakari, T.; Norrgren, L.; Sumpter, J.P.; Suter, M.J.F.; Svenson, A.; Pickering, A.D.

    2003-01-01

    Between January 1999 and December 2001, the European Community project COMPREHEND was performed. The overall aim of COMPREHEND was to assess endocrine disruption in the aquatic environment in Europe, consequent to effluent discharge, with emphasis on estrogenic activity. COMPREHEND demonstrated the

  16. Impact of Organic farming on aquatic environment

    OpenAIRE

    Kristensen, Erik Steen; Knudsen, Marie Trydemann

    2004-01-01

    The effects of conversion to organic farming on N leaching are discussed in the presentation. Problems in European aquatic environment are presented along with the development of organic farming in Denmark and the rest of Europe. Recent Danish studies on the N leaching effects by conversion of mixed dairy and arable farms are presented. The studies estimate that N leaching is lower from organic compared to conventional mixed dairy farms, whereas N leaching at organic arable farms are comparab...

  17. Nano-plastics in the aquatic environment.

    Science.gov (United States)

    Mattsson, K; Hansson, L-A; Cedervall, T

    2015-10-01

    The amount of plastics released to the environment in modern days has increased substantially since the development of modern plastics in the early 1900s. As a result, concerns have been raised by the public about the impact of plastics on nature and on, specifically, aquatic wildlife. Lately, much attention has been paid to macro- and micro-sized plastics and their impact on aquatic organisms. However, micro-sized plastics degrade subsequently into nano-sizes whereas nano-sized particles may be released directly into nature. Such particles have a different impact on aquatic organisms than larger pieces of plastic due to their small size, high surface curvature, and large surface area. This review describes the possible sources of nano-sized plastic, its distribution and behavior in nature, the impact of nano-sized plastic on the well-being of aquatic organisms, and the difference of impact between nano- and micro-sized particles. We also identify research areas which urgently need more attention and suggest experimental methods to obtain useful data. PMID:26337600

  18. Sunlight-induced Transformations of Graphene-based Nanomaterials in Aquatic Environments

    Science.gov (United States)

    Graphene-based nanomaterials and other related carbon nanomaterials (CNMs) can be released from products during their life cycles. Upon entry into aquatic environments, they are potentially transformed by photochemical reactions, oxidation reactions and biological processes, all ...

  19. Biofilm-flow interactions in aquatic environments

    Science.gov (United States)

    Christensen, K. T.; Kazemifar, F.; Blois, G.; Aybar, M.; Perez Calleja, P.; Nerenberg, R.; Sinha, S.; Hardy, R. J.; Best, J.; Sambrook Smith, G.

    2015-12-01

    Biofilms are pervasive in aquatic environments, growing in pipes and channels in water supply systems, on permeable riverbeds, etc. The permeable, heterogeneous, and deformable structure of the biofilms make their interaction with surrounding fluid flow important from a range of perspectives, such as mass and momentum transport, and biofilm deformation and detachment due to shear stresses. Our understanding of these processes is limited, in part due to technical obstacles for performing such measurements. We have attempted to address these challenges using particle image velocimetry (PIV) and fluorescence imaging techniques in a water channel flow facility to obtain time-resolved velocity vector fields of flow around cylinders covered with biofilms at different growth stages. Analysis is focused on the coupled dynamics of turbulence and the biofilm development under different flow and nutrient conditions.

  20. Consequences of radioactive deposition on aquatic environments

    International Nuclear Information System (INIS)

    The publication concentrates on the analyses of the main effects of radioactive deposition on Nordic aquatic environments. A modelling approach is applied for predicting the temporal behaviour of concentrations in fish of inland freshwater ecosystems. The observed values are considered in parallel with the calculations. The time-integrated consequences, the radiation doses are estimated for the relatively significant dose pathways. After a preliminary study of various lake environments in Nordic countries, three representative examples of lake systems were selected for closer consideration: small forest lake, medium-sized forest lake and mountain lake. The effects of changes in the trophic levels of lakes are also tentatively accounted for. The results of the analyses indicate that the radiological consequences of shallow forest lakes are greater than those of mountain lakes which usually have shorter turnover times compared to forest lakes. In long-term consideration, the fish ingestion pathway may in general become important and, in addition to the external exposure, has a high contribution to the expected doses. (orig.) (8 refs., 11 figs., 9 tabs.)

  1. Toxaphene in the aquatic environment of Greenland

    International Nuclear Information System (INIS)

    The octa- and nonachlorinated bornanes (toxaphene) CHBs 26, 40, 41, 44, 50 and 62 were analysed in Arctic char (Salvelinus alpinus), shorthorn sculpin (Myoxocephalus scorpius), ringed seal (Pusa hispida) and black guillemot eggs (Cepphus grylle) from Greenland. Despite their high trophic level, ringed seals had the lowest concentrations of these species, with a Σ6Toxaphene median concentration of 13–20 ng/g lipid weight (lw), suggesting metabolisation. The congener composition also suggests transformation of nona- to octachlorinated congeners. Black guillemot eggs had the highest concentrations (Σ6Toxaphene median concentration of 971 ng/g lw). Although concentrations were higher in East than in West Greenland differences were smaller than for other persistent organic pollutants. In a circumpolar context, toxaphene had the highest concentrations in the Canadian Arctic. Time trend analyses showed significant decreases for black guillemot eggs and juvenile ringed seals, with annual rates of −5 to −7% for Σ6Toxaphene. The decreases were generally steepest for CHBs 40, 41 and 44. - Highlights: • Toxaphene was detected in freshwater and marine species of Greenland. • Relatively low concentrations in ringed seal suggest metabolisation. • The concentrations in Greenland appear lower than those in the Canadian Arctic. • Significant decreases were found in juvenile ringed seals and black guillemot eggs. - The banned insecticide toxaphene is widely present in the aquatic environment of Greenland, but concentrations are decreasing

  2. ECOLOGICAL IMPACT OF INTEGRATED CHEMICAL AND BIOLOGICAL AQUATIC WEED CONTROL

    Science.gov (United States)

    This final report presents results of a four-year study of the ecological impacts of chemical, biological, and integrated methods of aquatic weed control. Biological and water quality changes occurred as abundance of macrophytic vegetation was altered by natural factors or manage...

  3. Are we going about chemical risk assessment for the aquatic environment the wrong way?

    OpenAIRE

    Johnson, Andrew C.; Sumpter, John P.

    2016-01-01

    The goal of protecting the aquatic environment through testing thousands of chemicals against hundreds of aquatic species with thousands of endpoints while also considering mixtures is impossible given the present resources. Much of the impetus for studies on micropollutants, such as pharmaceuticals, came from the topic of endocrine disruption in wild fish. But despite concern over reductions in fish fertility, there is little evidence that fish populations are in peril. Indeed, fish biologis...

  4. Freshwater ecosystems and aquatic insects: a paradox in biological invasions.

    Science.gov (United States)

    Fenoglio, Stefano; Bonada, Núria; Guareschi, Simone; López-Rodríguez, Manuel J; Millán, Andrés; Tierno de Figueroa, J Manuel

    2016-04-01

    Biological invasions have increased significantly in response to global change and constitute one of the major causes of biodiversity loss. Insects make up a large fraction of invasive species, in general, and freshwaters are among the most invaded ecosystems on our planet. However, even though aquatic insects dominate most inland waters, have unparalleled taxonomic diversity and occupy nearly all trophic niches, there are almost no invasive insects in freshwaters. We present some hypotheses regarding why aquatic insects are not common among aquatic invasive organisms, suggesting that it may be the result of a suite of biological, ecological and anthropogenic factors. Such specific knowledge introduces a paradox in the current scientific discussion on invasive species; therefore, a more in-depth understanding could be an invaluable aid to disentangling how and why biological invasions occur. PMID:27072403

  5. Determination of the Biologically Relevant Sampling Depth for Terrestrial and Aquatic Ecological Risk Assessments (Final Report)

    Science.gov (United States)

    This technical paper provides defensible approximations for what the depth of the biologically active zone, or “biotic zone” is within certain environments. The methods used in this study differ somewhat between Part 1 (Terrestrial Biotic Zone) and Part 2 (Aquatic Biotic Zone). ...

  6. Artificial Radiotracer Applications in Aquatic Environments

    International Nuclear Information System (INIS)

    The use of artificial radiotracers in the environment is analogous to their use in the human body. In both domains they provide data on flow rates and pathways, on exchange with materials and on their final discharge from the studied system. Artificially injected radiotracers have been used to investigate flow in natural waters since the 1950's. Identification of flow paths, diagnosis of blockages or leakage, measurement of flow rates, dispersion and exchange processes, such as biological uptake or sorption, are all aspects to which a wide range of artificial radioactive tracers have been applied. Increasingly radiotracers are used in combination with numerical modelling to improve confidence in the predictive capacity of models used in the management of our water resources and to extend their spatial applicability. In turn this allows us to use less and less tracer and demonstrate that the human and environmental impact of modern radiotracer studies is minimal. (author)

  7. Radiation biology for environment

    International Nuclear Information System (INIS)

    Environmental pollution problems such as the green-house effect by increase of CO2, acid rain caused by flue gases, and contamination of chemicals and pesticides in foods and water, have become serious in the world with the rapid development of industry and agriculture. To solve some of these problems, radiation treatment has being applied for the removal of the contaminants from flue gases and waste water from industrial plants. On the other hand, the contribution of radiation biology for these environmental pollution problems is not direct but it has contributed indirectly in many fields. This paper describes the contributions of radiation biology for environment in the following two topics: 1) control of insects and microorganisms, and 2) application of radiation for agricultural wastes

  8. Biological monitoring of aquatic ecosystems in Italy

    Directory of Open Access Journals (Sweden)

    Renato BAUDO

    2001-09-01

    Full Text Available In Italy, Ecotoxicology has found a place with the Legislative Decree n. 152 (May 11, 1999, emanated in fulfilment of the Directives 91/271/CEE "urban waste-water treatment" and 91/676/CEE "protection of waters against pollution caused by nitrates from agricultural sources". This decree in reality goes beyond (actually anticipating the content of the Framework Directive on Water, still under way of elaboration, and charges the Regions with the duty to identify, for all and each water body, the class of quality on the basis of a chemical and biological monitoring and their classification according to the environmental quality objectives. To this aim, for all water bodies (lakes, rivers, groundwater, coastal waters the ecological, chemical, and environmental status must be assessed by measuring specific parameters. This paper briefly summarises the role of biological monitoring in the classification of waters in five different categories, ranking from High to Foul Environmental status.

  9. Actinide elements in aquatic and terrestrial environments

    International Nuclear Information System (INIS)

    Progress is reported on the following research projects: water-sediment interactions of U, Pu, Am, and Cm; relative availability of actinide elements from abiotic to aquatic biota; comparative uptake of transuranic elements by biota bordering Pond 3513; metabolic reduction of 239Np from Np(V) to Np(IV) in cotton rats; evaluation of hazards associated with transuranium releases to the biosphere; predicting Pu in bone; adsorption--solubility--complexation phenomena in actinide partitioning between sorbents and solution; comparative soil extraction data; and comparative plant uptake data

  10. Monitoring aquatic environments with autonomous systems

    DEFF Research Database (Denmark)

    Christensen, Jesper Philip Aagaard

    High frequency measurements from autonomous sensors have become a widely used tool among aquatic scientists. This report focus primarily on the use of ecosystem metabolism based on high frequency oxygen measurements and relates the calculations to spatial variation, biomass of the primary producers...... in epilimnion were primarily a result of metabolism and gas exchange with the atmosphere, while only 10% of the variation was due to physical movement of water across the thermocline. 3) Dense macrophyte populations in oligotrophic systems may have a higher GPP than expected based on nutrient...... conditions in the water phase and in shallow systems the macrophytes can completely dominate primary production. This was despite the fact that the plants in the studied system were light-saturated most of the light hours and occasionally carbon limited. It was also shown that the GPP and the total...

  11. Actinide elements in aquatic and terrestrial environments

    International Nuclear Information System (INIS)

    Progress is reported in terrestrial ecology studies with regard to plutonium in biota from the White Oak Creek forest; comparative distribution of plutonium in two forest ecosystems; an ecosystem model of plutonium dynamics; actinide element metabolism in cotton rats; and crayfish studies. Progress is reported in aquatic studies with regard to transuranics in surface waters, frogs, benthic algae, and invertebrates from pond 3513; and radioecology of transuranic elements in cotton rats bordering waste pond 3513. Progress is also reported in stability of trivalent plutonium in White Oak Lake water; chemistry of plutonium, americium, curium, and uranium in pond water; uranium, thorium, and plutonium in small mammals; and effect of soil pretreatment on the distribution of plutonium

  12. APPLICATION OF SALMONIDS (SALMONIDAE N THE BIOMONITORING OF AQUATIC ENVIRONMENT (REVIEW

    Directory of Open Access Journals (Sweden)

    D. Yanovych

    2016-03-01

    Full Text Available Purpose. Due to the pollution of fisheries water bodies by industrial and agricultural waste waters, as well as by xenobiotics coming from other sources, taking into account a pridictable increase in the amounts of such effluents in the short and long terms, the problems related to the study of the effects of the pollutants of different nature and origin on aquatic organisms, especially fish, as well as a prediction of possible adverse consequences on aquatic ecosystems, becomes particularly important. The aim of our work was an analysis and synthesis of existing literature data concerning the indication in the biomonitoring of aquatic environments based on biological markers of salmonids as highly sensitive objects of fish fauna to external factors. Findings. The review summarizes and systematizes the data concerning the use of salmonids in biomonitoring studies. Furthermore, we highlighted and characterized the specificity of bioindication parameters of the aquatic environment state, such as the biochemical, genetic, physiological, morphological, histopathological, behavioral and population markers and noted the effects of hydroecosystem ecotoxication on different levels of biological organization (cell, individual, population, fish community. We also described the possibility of biological monitoring based on saprobic indexes identified for indicator species belonging to salmonids. Originality. In the article describes the structure, pros and cons of the use of specific biomarkers of individual salmonid fish and their populations for assessing the ecological status of aquatic environments. Practical value. The data given in the article can be used to improve the system of the ecological monitoring of aquatic environments by extending the range of indicator indices with organism and population biomarkers of highly sensitive salmonid species.

  13. Hazardous materials in aquatic environments of the Mississippi River Basin. Quarterly project status report, July 1, 1994--September 30, 1994

    International Nuclear Information System (INIS)

    This document references information pertaining to the presence of hazardous materials in the Mississippi River Basin. Topics discussed include: The biological fate, transport, and ecotoxicity of toxic and hazardous wastes; biological uptake and metabolism; sentinels of aquatic contamination; bioremediation; microorganisms; biomarkers of exposure and ecotoxicity; expert geographical information systems for assessing hazardous wastes in aquatic environments; and enhancement of environmental education at Tulane and Xavier

  14. Learning from data for aquatic and geothenical environments

    NARCIS (Netherlands)

    Bhattacharya, B.

    2005-01-01

    The book presents machine learning as an approach to build models that learn from data, and that can be used to complement the existing modelling practice in aquatic and geotechnical environments. It provides concepts of learning from data, and identifies segmentation (clustering), classification, r

  15. LEVELS OF SYNTHETIC MUSKS COMPOUNDS IN AQUATIC ENVIRONMENT

    Science.gov (United States)

    Synthetic musk compounds are consumer chemicals manufactured as fragrance materials Due to their high worldwide usage and release, they frequently occur in the aquatic and marine environments. The U.S. EPA (ORD, Las Vegas) developed surface-water monitoring methodology and conduc...

  16. Measurements for modeling radionuclide transfer in the aquatic environment

    International Nuclear Information System (INIS)

    Analytical methods for measuring radionuclides in the aquatic environment are discussed for samples of fresh water and seawater, fish and shellfish, biota such as algae, plankton, seaweed, and aquatic plants, and sediment. Consideration is given to radionuclide collection and concentration, sample preservation, radiochemical and instrumental analysis, and quality assurance. Major problems are the very low environmental levels of the radionuclides of interest, simultaneous occurrence of radionuclides in several chemical and physical forms and the numerous factors that affect radionuclide levels in and transfers among media. Some radionuclides of importance in liquid effluents from nuclear power stations are listed, and sources of radiochemical analytical methods are recommended

  17. Plutonium in the aquatic environment around the Rocky Flats facility

    International Nuclear Information System (INIS)

    The Rocky Flats Plant of the United States Energy Research and Development Administration has been fabricating and chemically recovering plutonium for over 20 years. During that time, small amounts of plutonium have been released with liquid process and sanitary waste discharges. The liquid waste flows through a series of holding ponds from which it is discharged into a creek that is part of a municipal drinking water supply. The water flows for about 1.5 km between the last holding pond and the municipal drinking water reservoir. In addition, liquid wastes containing high levels of chemical contaminants and plutonium concentrations less than allowable drinking water standards have been discharged to large evaporation ponds. The fate of the plutonium in both the surface and subsurface aquatic environment has been extensively monitored and studied. It has been found that plutonium does not move very far or very rapidly through subsurface water. The majority of the plutonium released through surface water has been contained in the sediments of the plant holding ponds. Small amounts of plutonium have also been found in the sediments of the draining creek and in the sediments of the receiving reservoir. Higher than normal amounts of plutonium were released from the waste treatment plants during times when suspended solids were high. Various biological species have been examined and plutonium concentration factors determined. Considerably less than 1% of the 210 mCi of plutonium released has been detected in biological systems including man. After more than 20 years of large scale operations, no health or environmental hazard has been identified due to the release of small amounts of plutonium. (author)

  18. Molecular ecology of aquatic microbes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    Abstracts of reports are presented from a meeting on Molecular Ecology of Aquatic Microbes. Topics included: opportunities offered to aquatic ecology by molecular biology; the role of aquatic microbes in biogeochemical cycles; characterization of the microbial community; the effect of the environment on aquatic microbes; and the targeting of specific biological processes.

  19. Hazardous materials in aquatic environments of the Mississippi River Basin

    International Nuclear Information System (INIS)

    Tulane and Xavier Universities have singled out the environment as a major strategic focus for research and training for now and by the year 2000. In December, 1992, the Tulane/Xavier CBR was awarded a five year grant to study pollution in the Mississippi River system. The ''Hazardous Materials in Aquatic Environments of the Mississippi River Basin'' project is a broad research and education program aimed at elucidating the nature and magnitude of toxic materials that contaminate aquatic environments of the Mississippi River Basin. Studies include defining the complex interactions that occur during the transport of contaminants, the actual and potential impact on ecological systems and health, and the mechanisms through which these impacts might be remediated. The Mississippi River Basin represents a model system for analyzing and solving contamination problems that are found in aquatic systems world-wide. These research and education projects are particularly relevant to the US Department of Energy's programs aimed at addressing aquatic pollution problems associated with DOE National Laboratories. First year funding supported seven collaborative cluster projects and twelve initiation projects. This report summarizes research results for period December 1992--December 1993

  20. Chapter 1. Chlorofluorocarbons in aquatic environments

    International Nuclear Information System (INIS)

    This guidebook brings together the results of some of these studies, as they apply to the groundwater environment, and summarizes the principles of CFC dating, with special emphasis on applications and limitations of the methods. Methods of sample collection and analysis are also presented, along with new software to aid in the interpretation of measured groundwater concentrations of CFCs. Often the application of multiple environmental tracers to a particular hydrological system enhances the level of understanding that can be gained. Applications of CFCs in groundwater studies will complement and enhance uses of other atmospheric environmental tracers in the hydrological sciences, including uses of tritium and tritium/helium-3 and sulphur hexafluoride. In the southern hemisphere and in low latitude/equatorial regions, the CFCs are particularly promising additional tools for groundwater dating because of very low tritium levels prevailing there and the associated problems for tritium dating. In addition, those regions were not affected so much by local industrial CFC emissions, as was the case for decades in western Europe and in the USA. However, the potential of applications for CFCs as groundwater tracers in low latitude regions has not yet been fully explored

  1. Biological conservation of aquatic inland habitats: these are better days

    Directory of Open Access Journals (Sweden)

    Ian J. Winfield

    2013-08-01

    Full Text Available The biodiversity of aquatic inland habitats currently faces unprecedented threats from human activities. At the same time, although much is known about the functioning of freshwater ecosystems the successful transfer of such knowledge to practical conservation has not been universal. Global awareness of aquatic conservation issues is also hampered by the fact that conditions under the water surface are largely hidden from the direct experience of most members of society. Connectivity, or lack of it, is another challenge to the conservation of freshwater habitats, while urban areas can play a perhaps unexpectedly important positive role. Freshwater habitats frequently enjoy benefits accruing from a sense of ownership or stewardship by local inhabitants, which has led to the development of conservation movements which commonly started life centred on the aquatic inland habitat itself but of which many have now matured into wider catchment-based conservation programmes. A demonstrable need for evidence-based conservation management in turn requires scientific assessments to be increasingly robust and standardised, while at the same time remaining open to the adoption of technological advances and welcoming the rapidly developing citizen science movement. There is evidence of real progress in this context and conservation scientists are now communicating their findings to environmental managers in a way and on a scale that was rarely seen a couple of decades ago. It is only in this way that scientific knowledge can be efficiently transferred to conservation planning, prioritisation and ultimately management in an increasingly scaled-up, joined-up and resource-limited world. The principle of ‘prevention is better than cure’ is particularly appropriate to most biological conservation issues in aquatic inland habitats and is inextricably linked to educating and/or nudging appropriate human behaviours. When prevention fails, some form of emergency

  2. Occurrence of aminopolycarboxylates in the aquatic environment of Germany

    International Nuclear Information System (INIS)

    Aminopolycarboxylic acids, such as ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), diethylenetriaminepentaacetic acid (DTPA), 1,3-propylenediaminetetraacetic acid (1,3-PDTA), β-alaninediacetic acid (β-ADA), and methylglycinediacetic acid (MGDA), are used in large quantities in a broad range of industrial applications and domestic products in order to solubilize or inactivate various metal ions by complex formation. Due to the wide field of their application, their high polarity and partly low degradability, these substances reach the aquatic environment at considerable concentrations (in the μg/L-range) and have also been detected in drinking water. This review evaluates and summarizes the results of long-term research projects, monitoring programs, and published papers concerning the pollution of the aquatic environment by aminopolycarboxylates in Germany. Concentrations and loads of aminopolycarboxylates are presented for various types of water including industrial and domestic waste waters, surface waters (rivers and lakes), raw waters, and drinking waters

  3. Nutrition considerations in special environments for aquatic sports.

    Science.gov (United States)

    Stellingwerff, Trent; Pyne, David B; Burke, Louise M

    2014-08-01

    Elite athletes who compete in aquatic sports face the constant challenge of arduous training and competition schedules in difficult and changing environmental conditions. The huge range of water temperatures to which swimmers and other aquatic athletes are often exposed (16-31 °C for open-water swimming), coupled with altered aquatic thermoregulatory responses as compared with terrestrial athletes, can challenge the health, safety, and performance of these athletes. Other environmental concerns include air and water pollution, altitude, and jetlag and travel fatigue. However, these challenging environments provide the potential for several nutritional interventions that can mitigate the negative effects and enhance adaptation and performance. These interventions include providing adequate hydration and carbohydrate and iron intake while at altitude; optimizing body composition and fluid and carbohydrate intake when training or competing in varying water temperatures; and maximizing fluid and food hygiene when traveling. There is also emerging information on nutritional interventions to manage jetlag and travel fatigue, such as the timing of food intake and the strategic use of caffeine or melatonin. Aquatic athletes often undertake their major global competitions where accommodations feature cafeteria-style buffet eating. These environments can often lead to inappropriate choices in the type and quantity of food intake, which is of particular concern to divers and synchronized swimmers who compete in physique-specific sports, as well as swimmers who have a vastly reduced energy expenditure during their taper. Taken together, planned nutrition and hydration interventions can have a favorable impact on aquatic athletes facing varying environmental challenges. PMID:24937361

  4. Simplified Method for Dissolved DNA Determination in Aquatic Environments

    OpenAIRE

    DeFlaun, Mary F.; Paul, John H.; Davis, Dean

    1986-01-01

    A method was developed for the determination of dissolved DNA in aquatic environments. The method is based upon the concentration of dissolved DNA by ethanol precipitation of 0.2-μm-pore-size filtered water. The DNA in concentrated extracts was quantified by the fluorescence of Hoechst 33258-DNA complexes. Fluorescence not attributable to DNA was corrected for by DNase I digestion of the extracts and averaged 25% of the total fluorescence for all samples. The effectiveness of the procedure fo...

  5. DISSIPATION AND ENVIRONMENTAL RISK OF FIPRONIL ON AQUATIC ENVIRONMENT

    OpenAIRE

    JOAQUIM G. MACHADO-NETO; MAYRA A.P. FIGUEIREDO; WILSON G. MANRIQUE

    2013-01-01

    Pesticides have been used in agriculture to avoid productivity losses caused by various organisms. However, the indiscriminate use of these chemicals has resulted in negative impacts on the environment, such as residues in soil, water, air, plants and animals. Fipronil is a phenylpyrazole insecticide widely used in agricultural management to control pests of sugar cane in Brazil, and it can be leached into aquatic ecosystems. The present study aimed to evaluate the environmental risk of toxic...

  6. Birds as Bioindicators of Pollution in Aquatic and Terrestrial Environments

    OpenAIRE

    Cotín Martínez, Javier

    2012-01-01

    [eng] Birds have been widely used as bioindicators. In this study we face the use of birds as bioindicators of metal pollution in two different scenarios of contamination: one that takes place in an aquatic environment, the Ebro river basin, and a second that occurs in a terrestrial environment, the Bolivian Andes. In the case of the Ebro river basin, the pollution threat is a factory located at the river bend, close to Flix, that due to its long operational activity and along with the co...

  7. 1988 activity report of the Atmospheric and Aquatic Environment Department

    International Nuclear Information System (INIS)

    The 1988 activity report of the Atmospheric and Aquatic Environment Department of EDF (Electricity of France) is presented. The activities are focused on the following subjects: development studies in the fields of hydraulic, hydrobiology, meteorology and atmospheric polluants physico-chemistry; application studies involving data analysis from operating or under development power systems; actions concerning cooperation with the Minister of the Environment and the Minister of the Industry. The investigations related to water and atmosphere are reported, as well as congress communications and papers

  8. Silver nanoparticles in aquatic environments: Physiochemical behavior and antimicrobial mechanisms.

    Science.gov (United States)

    Zhang, Chiqian; Hu, Zhiqiang; Deng, Baolin

    2016-01-01

    Nanosilver (silver nanoparticles or AgNPs) has unique physiochemical properties and strong antimicrobial activities. This paper provides a comprehensive review of the physicochemical behavior (e.g., dissolution and aggregation) and antimicrobial mechanisms of nanosilver in aquatic environments. The inconsistency in calculating the Gibbs free energy of formation of nanosilver [ΔGf(AgNPs)] in aquatic environments highlights the research needed to carefully determine the thermodynamic stability of nanosilver. The dissolutive release of silver ion (Ag(+)) in the literature is often described using a pseudo-first-order kinetics, but the fit is generally poor. This paper proposes a two-stage model that could better predict silver ion release kinetics. The theoretical analysis suggests that nanosilver dissolution could occur under anoxic conditions and that nanosilver may be sulfidized to form silver sulfide (Ag2S) under strict anaerobic conditions, but more investigation with carefully-designed experiments is required to confirm the analysis. Although silver ion release is likely the main antimicrobial mechanism of nanosilver, the contributions of (ion-free) AgNPs and reactive oxygen species (ROS) generation to the overall toxicity of nanosilver must not be neglected. Several research directions are proposed to better understand the dissolution kinetics of nanosilver and its antimicrobial mechanisms under various aquatic environmental conditions. PMID:26519626

  9. Progestagens for human use, exposure and hazard assessment for the aquatic environment

    Energy Technology Data Exchange (ETDEWEB)

    Besse, Jean-Philippe [Unite Biologie des ecosystemes aquatiques, Laboratoire d' ecotoxicologie, Cemagref, 3bis quai Chauveau CP 220, 69336 Lyon cedex 09 (France); Garric, Jeanne, E-mail: jeanne.garric@cemagref.f [Unite Biologie des ecosystemes aquatiques, Laboratoire d' ecotoxicologie, Cemagref, 3bis quai Chauveau CP 220, 69336 Lyon cedex 09 (France)

    2009-12-15

    Little information is available on the environmental occurrence and ecotoxicological effects of pharmaceutical gestagens released in the aquatic environment. Since eighteen different gestagens were found to be used in France, preliminary exposure and hazard assessment were done. Predicted environmental concentrations (PECs) suggest that if parent gestagens are expected to be found in the ng l{sup -1} range, some active metabolites could be present at higher concentrations, although limited data on metabolism and environmental fate limit the relevance of PECs. The biological effects are not expected to be restricted to progestagenic activity. Both anti-androgenic activity (mainly for cyproterone acetate, chlormadinone acetate and their metabolites) and estrogenic activity (mainly for reduced metabolites of levonorgestrel and norethisterone) should also occur. All these molecules are likely to have a cumulative effect among themselves or with other xenoestrogens. Studies on occurrence, toxicity and degradation time are therefore needed for several of these compounds. - Gestagens exposure and hazard assessment for the aquatic environment.

  10. Progestagens for human use, exposure and hazard assessment for the aquatic environment

    International Nuclear Information System (INIS)

    Little information is available on the environmental occurrence and ecotoxicological effects of pharmaceutical gestagens released in the aquatic environment. Since eighteen different gestagens were found to be used in France, preliminary exposure and hazard assessment were done. Predicted environmental concentrations (PECs) suggest that if parent gestagens are expected to be found in the ng l-1 range, some active metabolites could be present at higher concentrations, although limited data on metabolism and environmental fate limit the relevance of PECs. The biological effects are not expected to be restricted to progestagenic activity. Both anti-androgenic activity (mainly for cyproterone acetate, chlormadinone acetate and their metabolites) and estrogenic activity (mainly for reduced metabolites of levonorgestrel and norethisterone) should also occur. All these molecules are likely to have a cumulative effect among themselves or with other xenoestrogens. Studies on occurrence, toxicity and degradation time are therefore needed for several of these compounds. - Gestagens exposure and hazard assessment for the aquatic environment.

  11. High Molecular Weight Petrogenic and Pyrogenic Hydrocarbons in Aquatic Environments

    Science.gov (United States)

    Abrajano, T. A., Jr.; Yan, B.; O'Malley, V.

    2003-12-01

    Geochemistry is ultimately the study of sources, movement, and fate of chemicals in the geosphere at various spatial and temporal scales. Environmental organic geochemistry focuses such studies on organic compounds of toxicological and ecological concern (e.g., Schwarzenbach et al., 1993, 1998; Eganhouse, 1997). This field emphasizes not only those compounds with potential toxicological properties, but also the geological systems accessible to the biological receptors of those hazards. Hence, the examples presented in this chapter focus on hydrocarbons with known health and ecological concern in accessible shallow, primarily aquatic, environments.Modern society depends on oil for energy and a variety of other daily needs, with present mineral oil consumption throughout the 1990s exceeding 3×109 t yr-1 (NRC, 2002). In the USA, e.g., ˜40% of energy consumed and 97% of transportation fuels are derived from oil. In the process of extraction, refinement, transport, use, and waste production, a small but environmentally significant fraction of raw oil materials, processed products, and waste are released inadvertently or purposefully into the environment. Because their presence and concentration in the shallow environments are often the result of human activities, these organic materials are generally referred to as "environmental contaminants." Although such reference connotes some form of toxicological or ecological hazard, specific health or ecological effects of many organic "environmental contaminants" remain to be demonstrated. Some are, in fact, likely innocuous at the levels that they are found in many systems, and simply adds to the milieu of biogenic organic compounds that naturally cycle through the shallow environment. Indeed, virtually all compounds in crude oil and processed petroleum products have been introduced naturally to the shallow environments as oil and gas seepage for millions of years ( NRC, 2002). Even high molecular weight (HMW) polyaromatic

  12. DISSIPATION AND ENVIRONMENTAL RISK OF FIPRONIL ON AQUATIC ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    JOAQUIM G. MACHADO-NETO

    2013-06-01

    Full Text Available Pesticides have been used in agriculture to avoid productivity losses caused by various organisms. However, the indiscriminate use of these chemicals has resulted in negative impacts on the environment, such as residues in soil, water, air, plants and animals. Fipronil is a phenylpyrazole insecticide widely used in agricultural management to control pests of sugar cane in Brazil, and it can be leached into aquatic ecosystems. The present study aimed to evaluate the environmental risk of toxic concentrations and dissipation of fipronil to Poecilia reticulata, based on the 96-h median lethal concentration (LC50 value estimated at 0.08 ± 0.01 mg/L without sediment and 0.09 ± 0.01 mg/L with sediment of fipronil in the aquatic environment. These values of fipronil were classified as extremely toxic to P. reticulata in both cases, which showed high environmental risk of poisoning to a shallow film of water of 1 ha and 0.30 m deep, with and without sediment. On the other hand, in bodies of water 1 ha and 2.0 m deep, it was of moderate toxicity. Dissipation of fipronil in the water was not affected by temperature, sediment or photoperiod. The minimum time to which fipronil caused 50% acute mortality (0.08 mg/L after dilution of 0.75 mg/L was 242 days; the withdrawal period, after which no mortality occurs (0.025 mg/L, was 263 days.

  13. Environmental protection and stewardship of subglacial aquatic environments

    Science.gov (United States)

    Doran, Peter T.; Vincent, Warwick F.

    Environmental stewardship is a guiding principle of the Antarctic Treaty System. Efforts began in the 1990s to generate specific guidelines for stewardship of many terrestrial environments, including surface lakes and rivers. The relatively recent documentation of widespread subglacial aquatic environments, and planning for acquiring samples from them, has generated a need for stewardship guidelines for these environments. In response to a request from the U.S. National Science Foundation, the National Research Council of the National Academies of Sciences (NAS) created the Committee on the Principles of Environmental and Scientific Stewardship for the Exploration and Study of Subglacial Environments. The committee made 13 recommendations and a decision tree as a framework and flow chart for environmental management decisions. The committee report was also largely the basis of a Code of Conduct (CoC) for the exploration of subglacial environments formulated by a Scientific Committee on Antarctic Research Action Group. Both the NAS report and CoC have been used as guidance, to varying degrees, by subglacial research currently in progress.

  14. Forestry and the aquatic environment: studies in an Irish context

    Directory of Open Access Journals (Sweden)

    P. S. Giller

    2004-01-01

    Full Text Available Research on the interaction between plantation forestry and aquatic environments is essential to develop environmentally compatible and sustainable management further. Given, in Ireland, the generally low levels of atmospheric pollution, its geology and maritime climate, and the unique fauna and flora due to its island history, such studies are important not only in the regional context, but also internationally, as they provide an opportunity to examine the effect of forestry and forest management practices on aquatic systems per se, without the complications of acidification. Here, some of the major findings of forestry and water research in Ireland have been reviewed and compared with those from the UK and elsewhere. Plantation forests do not exacerbate acidification in the south of Ireland (Munster as a whole so that the influence of forestry on water chemistry is far less important than in other parts of the country (such as Wicklow and Mayo. The main forestry influence on streams in Munster is more likely through physical factors, but their nature is unclear. In a few catchments some negative effects are evident, but in many others apparently positive forest effects occur. In this context, smaller scale catchment-level effects appear to be more important in explaining the various relationships between plantation forests and stream ecology than larger scale regional factors. The management of riparian zones, particularly in forested catchments, is of major importance for the structure and functioning of aquatic communities and further work is needed on best management practices. It is suggested that it is unreasonable to base forest management on national Forest-Fisheries guidelines since regions vary too much and the signal from local conditions is too strong. The approach for environmentally benign, scientifically sound forestry management has to be at the catchment scale. Trees in the right places may be beneficial ecologically but

  15. Waste heat discharges in the aquatic environment -- impact and monitoring 2

    International Nuclear Information System (INIS)

    Studies on ecological impacts, on fishes in particular, of waste heat discharges in the aquatic environment are briefly reviewed. These studies cover the susceptibility of fishes to disease and predation, population biology, parasite proliferation and its impact on fishes, synergistic effects due to heat and other stresses such as chemicals, pollutant, lowering of saturation limit of dissolved oxygen at elevated temperature and radioactivity. Experiences of monitoring waste heat discharges at the Rajasthan Atomic Power Station (RAPS) and the Tarapur Atomic Power Station (TAPS) are presented. Entrainment losses and impingement losses are also reviewed. Requirements for thermal monitoring are mentioned. (M.G.B.)

  16. Natural and active chemical remediation of toxic metals and radionuclides in the aquatic environment

    International Nuclear Information System (INIS)

    The focus of this research is the non-biological, chemical remediation of toxic heavy metals and radionuclides in aquatic environments. This Tulane/Xavier group includes researchers from Chemistry, Chemical Engineering, and Geology. Active methods using novel zeolites and ion exchange membranes are currently being evaluated for use in removing heavy metals from natural waters. In addition, field and laboratory studies of metal ion exchange reactions and competitive, heavy metal adsorption on clay substrates are underway to determine sediment metal sequestering capacity. A summary of progress to date and future work is presented

  17. HAZARDOUS MATERIALS IN AQUATIC ENVIRONMENTS OF THE MISSISSIPPI RIVER BASIN

    Energy Technology Data Exchange (ETDEWEB)

    John A. McLachlan

    2003-12-01

    In December 1992, the CBR was awarded a five-year grant of $25M from the US Department of Energy Office of Environmental Management (DOE-EM) to study pollution in the Mississippi River system. The ''Hazardous Materials in Aquatic Environments of the Mississippi River Basin'' project was an interdisciplinary, collaborative research and education project aimed at elucidating the nature and magnitude of toxic materials that contaminate aquatic environments. This project funded 15 collaborative cluster multi-year projects and 41 one-year initiation projects out of 165 submitted research proposals. This project was carried out by 134 research and technical support faculty from Xavier University (School of Arts and Sciences, and College of Pharmacy) and Tulane University (Schools of Liberal Arts and Sciences, Engineering, Medicine, and Public Health and Tropical Medicine), and 173 publications and 140 presentations were produced. More than 100 graduate and undergraduate students were trained through these collaborative cluster and initiation research projects. Nineteen Tulane graduate students received partial funding to conduct their own competitively-chosen research projects, and 28 Xavier undergraduate LIFE Scholars and 30 LIFE Interns were supported with DOE funding to conduct their mentored research projects. Studies in this project have defined: (1) the complex interactions that occur during the transport of contaminants, (2) the actual and potential impact on ecological systems and health, and (3) the mechanisms through which these impacts might be remediated. The bayou and spoil banks of Bayou Trepagnier were mapped and analyzed in terms of risks associated with the levels of hydrocarbons and metals at specific sample sites. Data from contaminated sample sites have been incorporated into a large database and used in GIS analyses to track the fate and transport of heavy metals from spoil banks into the surrounding marsh. These data are crucial

  18. Physical speciation of thorium in aquatic subsurface environment

    International Nuclear Information System (INIS)

    During this work laboratory simulated experiments were conducted to study the physical speciation of thorium by using ultrafiltration technique. Thorium has only one stable oxidation state i.e. IV, under all redox conditions in natural waters and therefore, its speciation is dominated by its interaction with various fraction of aquatic humic substances(AHS). Samples of water were collected from oligotropic environment having DOC in the range of 60 - 70 ppm. Th(IV) ions are extremely particle reactive having Kd value of the order of 106, hence to avoid adsorption on suspended particulate matter, spiking of the solution with Th(NO3)4 was carried out in ground water samples after filtering through 0.22 μm pore size using suction filtration. Experimental results show that 70% of the spiked Th is in association with low molecular weight colloids i.e 500 NMWL followed by < 500 NMWL. (author)

  19. Tulane/Xavier University Hazardous Materials in Aquatic Environments of the Mississippi River Basin. Quarterly progress report, January 1, 1995--March 31, 1995

    International Nuclear Information System (INIS)

    This progress report covers activities for the period January 1 - March 31, 1995 on project concerning 'Hazardous Materials in Aquatic Environments of the Mississippi River Basin.' The following activities are each summarized by bullets denoting significant experiments/findings: biotic and abiotic studies on the biological fate, transport and ecotoxicity of toxic and hazardous waste in the Mississippi River Basin; assessment of mechanisms of metal-induced reproductive toxicity in quatic species as a biomarker of exposure; hazardous wastes in aquatic environments: biological uptake and metabolism studies; ecological sentinels of aquatic contamination in the lower Mississippi River system; bioremediation of selected contaminants in aquatic environments of the Mississippi River Basin; a sensitive rapid on-sit immunoassay for heavy metal contamination; pore-level flow, transport, agglomeration and reaction kinetics of microorganism; biomarkers of exposure and ecotoxicity in the Mississippi River Basin; natural and active chemical remediation of toxic metals, organics and radionuclides in the aquatic environment; expert geographical information systems for assessing hazardous wastes in aquatic environments; enhancement of environmental education; and a number of just initiated projects including fate and transport of contaminants in aquatic environments; photocatalytic remediation; radionuclide fate and modeling from Chernobyl

  20. Tulane/Xavier University Hazardous Materials in Aquatic Environments of the Mississippi River Basin. Quarterly progress report, January 1, 1995--March 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    This progress report covers activities for the period January 1 - March 31, 1995 on project concerning `Hazardous Materials in Aquatic Environments of the Mississippi River Basin.` The following activities are each summarized by bullets denoting significant experiments/findings: biotic and abiotic studies on the biological fate, transport and ecotoxicity of toxic and hazardous waste in the Mississippi River Basin; assessment of mechanisms of metal-induced reproductive toxicity in quatic species as a biomarker of exposure; hazardous wastes in aquatic environments: biological uptake and metabolism studies; ecological sentinels of aquatic contamination in the lower Mississippi River system; bioremediation of selected contaminants in aquatic environments of the Mississippi River Basin; a sensitive rapid on-sit immunoassay for heavy metal contamination; pore-level flow, transport, agglomeration and reaction kinetics of microorganism; biomarkers of exposure and ecotoxicity in the Mississippi River Basin; natural and active chemical remediation of toxic metals, organics and radionuclides in the aquatic environment; expert geographical information systems for assessing hazardous wastes in aquatic environments; enhancement of environmental education; and a number of just initiated projects including fate and transport of contaminants in aquatic environments; photocatalytic remediation; radionuclide fate and modeling from Chernobyl.

  1. Are Aquatic Viruses a Biological Archive of Genetic Information from Universe?

    Science.gov (United States)

    Toparceanu, F.; Negoita, Gh. T.; Nita, I. I.; Sava, D.

    2009-04-01

    After 1990, when the viruses were admited as the most abundant lifeforms from aquatic environments, it became obvious that viral lysis had an essential role on release and recycling of nutrients. Studies on cellular cultures and modeling suggest that this is an important quantitative process. The viruses from oceans represent the widest source of genetic diversity on the Earth, uncharacterized yet. The ancient lifeforms records stretching back a million years are locked in ice caps. The trend of glaciers melting as effect of actual climate change will promote the release of ancient viruses from ice caps. The increasing of the freshwater layer led to the replace of some algae species by others. Law-Racovitza Station (69o23'S 76o23'E) from East Antarctica (Larsemann Hills Oasis) offers opportunities to study the Antarctic marine ecosystem, as well as archaic aquatic ecosystems from this area ( 150 lakes and waterways resulted from ice and snow melting during the austral summer). According to Law-Racovitza Station Scientific Program, we are performing studies regarding the effect of climate changes on virus-algae host relationship in these aquatic ecosystems. Phycodnaviruses, that infect the eukaryote algae, are comprised of ancient genes and they are considered a "peek" of genetic diversity useful in biological studies and exobiology regarding the evolution of genetic sequencing. The latest discoveries of the giant aquatic viruses open the unexpected perspectives for understanding the role of viral infection in global ecosystem; beyond the old concept which considered that the viruses were only etiological agents of human, animals and plants illnesses. The aquatic viruses which infect microalgae contain similar genes of other viruses, bacteria, arhebacteria and eukaryotes, all of them being on the same genome. Which is the signification of enormous abundance of viruses and excessive diversity of genetic information encoded by viruses? There is the possibility that

  2. Transuranic radionuclides dispersed into the aquatic environment, a bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V.E.; Stoker, A.C.; Wong, Kai M. [and others

    1994-04-01

    The purpose of this project was to compile a bibliography of references containing environmental transuranic radionuclide data. Our intent was to identify those parameters affecting transuranic radionuclide transport that may be generic and those that may be dependent on chemical form and/or environmental conditions (i.e., site specific) in terrestrial, aquatic and atmospheric environments An understanding of the unique characteristics and similarities between source terms and environmental conditions relative to transuranic radionuclide transport and cycling will provide the ability to assess and predict the long term impact on man and the environment. An additional goal of our literature review, was to extract the ranges of environmental transuranic radionuclide data from the identified references for inclusion in a data base. Related to source term, these ranges of data can be used to calculate the dose to man from the radionuclides, and to perform uncertainty analyses on these dose assessments. On the basis of our reviews, we have arbitrarily outlined five general source terms. These are fallout, fuel cycle waste, accidents, disposal sites and resuspension. Resuspension of the transuranic radionuclides is a unique source term, in that the radionuclides can originate from any of the other source terms. If these transuranic radionuclides become resuspended into the air, they then become important as a source of inhaled radionuclides.

  3. Tritium in the aquatic environment and the associated risk

    International Nuclear Information System (INIS)

    Tritium, which is naturally present in the environment under tritiated water form, participates to the global water cycle. Today, nuclear fuel cycle facilities represent the main source of man-made tritium. The civilian production is estimated to be about 2 x 104 TBq/y, corresponding to a third of the natural production. Due to the fact that tritium releases are very local, concentrations in water higher than natural background (of 0.1 to 0.9 Bq/l for surface waters) are observed around these sites. Measurements in French aquatic environment reveal tritium concentration generally below 10 Bq/1 for underground waters and below 20 Bq/l for rivers. Nevertheless, some ground waters and some rivers presents locally a concentration up to a few hundreds of Bq/l. Moreover, measurements performed in France are generally coherent with monitoring in other European countries. Furthermore, the associated radiological impact for a potential individual taking all this water needs from a 100 Bq/l tritiated water source, was evaluated to about one thousandth of the natural background. (authors)

  4. Safety assessment of boron in aquatic and terrestrial environments.

    Science.gov (United States)

    Butterwick, L; de Oude, N; Raymond, K

    1989-06-01

    Boron is a naturally occurring material and is used in industrial and domestic products. Its major release into the environment is through weathering processes and wastewater discharge. Boron is an essential nutrient for plants, but can above certain concentrations be toxic to aquatic and terrestrial organisms. This paper assesses the ecotoxicology and environmental safety of boron. It draws together the data for toxicological effects of boron and compares these with environmental concentrations of boron, measured in Europe and the U.S.A. Generally, environmental concentrations of boron found in surface water are below levels identified as toxic to aquatic organisms. Concentrations high enough to produce toxic effects in laboratory tests are found in areas where weathering of boron-rich formations and deposits occurs, such as in the southwestern United States. However, reproducing populations of the most sensitive species, rainbow trout, have been observed in surface waters in these regions, indicating no cause for concern. The prime concern for effects on terrestrial plants centers on the use of irrigation water with elevated levels of boron. At present, there is no evidence of widespread damage to crops resulting from this practice. In some areas, wastewater is used for irrigation and crops grown under these conditions are generally confined to those relatively insensitive to boron toxicity. Good irrigation practices will be necessary, however, in arid regions with high evapotranspiration rates and care will be needed when using wastewater, particularly in areas with naturally high boron levels. It is not anticipated that there will be any significant increase in the discharge of boron to the environment in the foreseeable future. The use of boron-containing products is expected to increase, but glass will remain the dominant market and the use of boron in detergents in Europe is expected to decrease due to the introduction of bleach activators and liquid

  5. Occurrence of veterinary pharmaceuticals in the aquatic environment in Flanders

    Science.gov (United States)

    Servaes, K.; Vanermen, G.; Seuntjens, P.

    2009-04-01

    There is a growing interest in the occurrence of pharmaceuticals in the aquatic environment. Pharmaceuticals are classified as so-called ‘emerging pollutants'. ‘Emerging pollutants' are not necessarily new chemical compounds. Often these compounds are already present in the environment for a long time. But, their occurrence and especially their impact on the environment has only recently become clear. Consequently, data on their occurrence are rather scarce. In this study, we focus on the occurrence of veterinary pharmaceuticals in surface water in Flanders. We have only considered active substances administered to cattle, pigs and poultry. Based on the literature and information concerning the use in Belgium, a selection of 25 veterinary pharmaceuticals has been made. This selection consists of the most important antibiotics and antiparasitic substances applied in veterinary medicine in Belgium. We develop an analytical methodology based on UPLC-MS/MS for the detection of these veterinary pharmaceuticals in surface water. Therefore, the mass characteristics as well as the optimum LC conditions will be determined. To obtain limits of detection as low as possible, the samples are concentrated prior to analysis using solid phase extraction (SPE). Different SPE cartridges will be tested during the method development. At first, this SPE sample pre-treatment is performed off-line. In a next step, online SPE is optimized for this purpose. The analytical procedure will be subject to an in-house validation study, thereby determining recovery, repeatability (% RSD), limits of detection and limits of quantification. Finally, the developed methodology will be applied for monitoring the occurrence of veterinary pharmaceuticals in surface water and groundwater in Flanders. These water samples will be taken in areas characterized by intensive cattle breeding. Moreover, the samples will be collected during springtime. In this season, farmers apply manure, stored during winter

  6. Surfactants in aquatic and terrestrial environment: occurrence, behavior, and treatment processes.

    Science.gov (United States)

    Jardak, K; Drogui, P; Daghrir, R

    2016-02-01

    Surfactants belong to a group of chemicals that are well known for their cleaning properties. Their excessive use as ingredients in care products (e.g., shampoos, body wash) and in household cleaning products (e.g., dishwashing detergents, laundry detergents, hard-surface cleaners) has led to the discharge of highly contaminated wastewaters in aquatic and terrestrial environment. Once reached in the different environmental compartments (rivers, lakes, soils, and sediments), surfactants can undergo aerobic or anaerobic degradation. The most studied surfactants so far are linear alkylbenzene sulfonate (LAS), quaternary ammonium compounds (QACs), alkylphenol ethoxylate (APEOs), and alcohol ethoxylate (AEOs). Concentrations of surfactants in wastewaters can range between few micrograms to hundreds of milligrams in some cases, while it reaches several grams in sludge used for soil amendments in agricultural areas. Above the legislation standards, surfactants can be toxic to aquatic and terrestrial organisms which make treatment processes necessary before their discharge into the environment. Given this fact, biological and chemical processes should be considered for better surfactants removal. In this review, we investigate several issues with regard to: (1) the toxicity of surfactants in the environment, (2) their behavior in different ecological systems, (3) and the different treatment processes used in wastewater treatment plants in order to reduce the effects of surfactants on living organisms. PMID:26590059

  7. Assessing pesticide exposure of the aquatic environment in tropical catchments

    Science.gov (United States)

    Weiss, Frederik; Zurbrügg, Christian; Eggen, Rik; Castillo, Luisa; Ruepert, Clemens; Stamm, Christian

    2015-04-01

    Today, pesticides are intensively used in agriculture across the globe. Worldwide about 2.4×106 tons of pesticides are used annually on 1.6×109 ha of arable land. This yields a global average use of pesticides of 1.53 kg ha-1 year-1. Available data suggest that the use in the agricultural sector will continue to grow. Recently it was estimated that within the last decade, the world pesticide market increased by 93% and the Brazilian market alone by 190%. Though pesticides are intensively used in many low and middle income countries (LAMICs), scientifically sound data of amounts and types of pesticide use and the resulting impact on water quality are lacking in many of these countries. Therefore it is highly relevant to: i) identify risk areas where pesticides affect environmental health, ii) understand the environmental behavior of pesticides in vulnerable tropical ecosystems; and iii) develop possible mitigation options to reduce their exposure to ecosystems and humans. Here we present a project that will focus on assessing pesticide exposure of the aquatic environment and humans in tropical catchments of LAMICs. A catchment in the Zarcero province in Costa Rica will be the test case. Pesticide exposure will be assessed by passive sampling. In order to cover a broad range of compounds of possible use, two sampling devices will be used: SDB membranes for collecting polar compounds and silicon sheets for accumulating apolar pesticides. Extracts will be subsequently analysed by GC-MSMS and LC-HRMS.

  8. Metal contents in tench otoliths: relationships to the aquatic environment.

    Science.gov (United States)

    Adami, G; Miletić, M; Siviero, P; Barbieri, P; Reisenhofer, E

    2001-01-01

    A monitoring of the quality of waters was attempted determining metal accumulation in target organs as otoliths of freshwater fish. Tenchs of age ranging between 2 and 10 years were sampled in three different canals receiving wastewater from industrial, agricultural and urban activities. Metal contents were determined in both lapilli and asterisci otoliths, using inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Analytical data are reported for minor metals and for some trace metals. Al, Fe and Zn have contents depending on the environment where the fish has lived, while Na, K, Ca and Sr contents are insensitive to the different aquatic habitat. Considering the two types of otolith separately, lapilli display a different affinity for trace metals (Al, Fe and Zn), while in asterisci this affinity is matched only for zinc. The high affinity of zinc for both types of otoliths suggests using this metal for discriminating the fresh waters by checking its accumulation in otoliths, as well as correlating this accumulation with age of the fish: a negative power curve equation is proposed. Since highest concentrations are found in individuals of 2-3 yr., it is advisable to use this fish for such environmental studies. PMID:11554178

  9. Enzyme-linked immunosorbent assay for triclocarban in aquatic environments.

    Science.gov (United States)

    Zeng, Kun; Zou, Yanmin; Liu, Jianxia; Wei, Wei; Zhang, Meng; Zhou, Jun; Zhang, Zhen; Gai, Zikuan

    2015-01-01

    A sensitive, competitive indirect enzyme-linked immunosorbent assay (ELISA) was developed for the detection of triclocarban (TCC) in waters and sediments. Haptens were synthesized by derivatizing the paraposition of a phenyl moiety of TCC. The synthesized hapten was then coupled to bovine thyroglobulin to be used as an immunogen, based on which, a high affinity monoclonal antibody 4D5 was produced with the hybridoma technique. Under the optimized conditions, using the monoclonal antibody, excellent performances of the assay were obtained: satisfactory sensitivity (IC50 (50% inhibition concentration) value, 0.43 ng/mL; limit of detection, 0.05 ng/mL); good linear range (0.05-10 ng/mL); and satisfactory accuracy (recoveries 70.7-107% in waters; 74.8-98.3% in sediments). Furthermore, TCC was found with the concentration ranging from not detected to 422.12 ng/L in waters and from 6.68 ng/g to 78.67 ng/g in sediments in Yunliang River, Ancient Canal and Hongqiao Port in Zhenjiang City. In conclusion ELISA could be applied for monitoring TCC in aquatic environments. PMID:26540528

  10. Bioavailability and Bioaccumulation of Metal-Based Engineered Nanomaterials in Aquatic Environments

    DEFF Research Database (Denmark)

    Luoma, Samuel; Khan, Farhan R.; Croteau, Marie-Noelle

    2014-01-01

    Bioavailability of Me-ENMs to aquatic organisms links their release into the environment to ecological implications. Close examination shows some important differences in the conceptual models that define bioavailability for metals and Me-ENMs. Metals are delivered to aquatic animals from Me-ENMs...

  11. Survival and detection of bacteria in an aquatic environment.

    Science.gov (United States)

    Amy, P S; Hiatt, H D

    1989-04-01

    A genetically engineered plasmid, pPSA131, was used as a DNA probe to detect homologous DNA in Escherichia coli HB101(pPSA131) after it was mixed with aquatic microorganisms from Lake Mead, Nevada, water samples. An isolate from the pLAFR1 chromosomal library of Pseudomonas syringae Cit 7 was used to detect parent P. syringae Cit 7 that had been mixed with Lake Mead water. E. coli(pPSA131) was kept in variously treated samples of lake water or buffer, and its survival was measured by viable cell counting on modified Luria-Bertani (LB) agar. Full-strength LB agar proved better than 0.1 x LB agar at recovering E. coli(pPSA131) after survival in low-nutrient environments. Survival of E. coli(pPSA131) remained high in filtered (0.22-micron pore size) lake water and salts buffer on both selective and nonselective agars but was lower in untreated lake water or lake water filtered with a 0.8-micron-pore-size membrane. Total recoverable colonies grown on LB agar were higher when lake water was filter treated (0.8-micron pore size) than when lake water was untreated. Microorganisms recovered from lake water alone grew rapidly on nonselective media, probably because of the "bottle effect." After being mixed with Lake Mead water, E. coli(pPSA131) and P. syringae were detected by colony blotting with non-radioactively labeled DNA probes. E. coli(pPSA131) were recovered at three times during 48 h from variously treated samples of lake water and from a mixture with Lake Mead water organisms. Colonies were supported on either nonselective or selective agar for comparison.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2658805

  12. The occurrence and ecological risk assessment of phthalate esters (PAEs) in urban aquatic environments of China.

    Science.gov (United States)

    Zhang, Lulu; Liu, Jingling; Liu, Huayong; Wan, Guisheng; Zhang, Shaowei

    2015-07-01

    Phthalate esters (PAEs) are widely used in the manufacturing of plastics, and the demand for PAEs has grown rapidly, especially in China. This trend will lead to much more environmental PAE contamination. PAEs are listed as priority substances in the European Union and are therefore subject to ecological risk assessments. This paper reviews the literature concerning the pollution status of PAEs and their ecological risk to aquatic environments. Risk quotients (RQs) based on the predicted no effect concentration and PAE concentrations in aquatic environments demonstrated significant (10 ≤ RQ effects for algae, Daphnia, and fish in aquatic environments near PAE-based industrial and urban areas. Thus, the ecological risk of PAEs in Chinese aquatic environments should be considered, especially in areas where commercial plastics are produced. PMID:25847103

  13. Sunlight affects aggregation and deposition of graphene oxide in the aquatic environment.

    Science.gov (United States)

    In this study, we investigate the role of simulated sunlight on the physicochemical properties, aggregation, and deposition of graphene oxide (GO) in aquatic environments. Results show that light exposure under varied environmental conditions significantly impacts the physicochem...

  14. NOVANA. National Monitering and Assessment Programme for the Aquatic and Terrestrial Environments

    DEFF Research Database (Denmark)

    Svendsen, L. M.; Bijl, L. van der; Boutrup, S.

    This report is Part 2 of the Programme Description of NOVANA - the National Monitoring and Assessment Programme for the Aquatic and Terrestrial Environments. Part 2 comprises a de-tailed description of the nine NOVANA subprogrammes: Background monitoring of air......This report is Part 2 of the Programme Description of NOVANA - the National Monitoring and Assessment Programme for the Aquatic and Terrestrial Environments. Part 2 comprises a de-tailed description of the nine NOVANA subprogrammes: Background monitoring of air...

  15. Ecology of aerobic anoxygenic phototrophs in aquatic environments

    Czech Academy of Sciences Publication Activity Database

    Koblížek, Michal

    2015-01-01

    Roč. 39, č. 6 (2015), s. 854-870. ISSN 0168-6445 R&D Projects: GA ČR GA13-11281S; GA MŠk LO1416 Institutional support: RVO:61388971 Keywords : photoheterotrophs * microbial loop * aquatic food webs Subject RIV: EE - Microbiology, Virology Impact factor: 13.244, year: 2014

  16. Survival and detection of bacteria in an aquatic environment.

    OpenAIRE

    Amy, P. S.; Hiatt, H D

    1989-01-01

    A genetically engineered plasmid, pPSA131, was used as a DNA probe to detect homologous DNA in Escherichia coli HB101(pPSA131) after it was mixed with aquatic microorganisms from Lake Mead, Nevada, water samples. An isolate from the pLAFR1 chromosomal library of Pseudomonas syringae Cit 7 was used to detect parent P. syringae Cit 7 that had been mixed with Lake Mead water. E. coli(pPSA131) was kept in variously treated samples of lake water or buffer, and its survival was measured by viable c...

  17. Biogenic Mn oxides for effective adsorption of Cd from aquatic environment

    International Nuclear Information System (INIS)

    Biogenic Mn oxides exert important controls on trace metal cycling in aquatic and soil environments. A Mn-oxidizing bacterium Bacillus sp. WH4 was isolated from Fe-Mn nodules of an agrudalf in central China. The biogenic Mn oxides formed by mediation of this Mn oxidizing microorganism were identified as short-ranged and nano-sized Mn oxides. Cd adsorption isotherms, pH effect on adsorption and kinetics were investigated in comparison with an abiotic Mn oxide todorokite. Maximum adsorption of Cd to the biogenic Mn oxides and todorokite was 2.04 and 0.69 mmol g-1 sorbent, respectively. Thus, the biogenic Mn oxides were more effective Cd adsorbents than the abiotic Mn oxide in the aquatic environment. The findings could improve our knowledge of biogenic Mn oxides formation in the environment and their important roles in the biogeochemical cycles of heavy metals. - Biogenic Mn oxides effectively adsorb Cd from aquatic environments.

  18. Biogenic Mn oxides for effective adsorption of Cd from aquatic environment

    Energy Technology Data Exchange (ETDEWEB)

    Meng Youting [State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Graduate School, Chinese Academy of Sciences, Beijing 100039 (China); Zheng Yuanming; Zhang Limei [State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); He Jizheng, E-mail: jzhe@rcees.ac.c [State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China)

    2009-08-15

    Biogenic Mn oxides exert important controls on trace metal cycling in aquatic and soil environments. A Mn-oxidizing bacterium Bacillus sp. WH4 was isolated from Fe-Mn nodules of an agrudalf in central China. The biogenic Mn oxides formed by mediation of this Mn oxidizing microorganism were identified as short-ranged and nano-sized Mn oxides. Cd adsorption isotherms, pH effect on adsorption and kinetics were investigated in comparison with an abiotic Mn oxide todorokite. Maximum adsorption of Cd to the biogenic Mn oxides and todorokite was 2.04 and 0.69 mmol g{sup -1} sorbent, respectively. Thus, the biogenic Mn oxides were more effective Cd adsorbents than the abiotic Mn oxide in the aquatic environment. The findings could improve our knowledge of biogenic Mn oxides formation in the environment and their important roles in the biogeochemical cycles of heavy metals. - Biogenic Mn oxides effectively adsorb Cd from aquatic environments.

  19. Assessment of Constructed Wetland Biological Integrity Using Aquatic Macroinvertebrates

    OpenAIRE

    C. Galbrand; I. G. Lemieux; Abdel E. Ghaly; Côté, R.; Verma, M.

    2007-01-01

    A surface flow constructed wetland consisting of seven cells was used to treat the leachates from a decommissioned landfill. Wetland monitoring was performed by evaluating the treatment efficiency of the landfill leachate and the wetland biological integrity of the wetland. The water quality samples were analyzed for iron, manganese, phosphorus (orthophosphate), pH, dissolved oxygen (DO), nitrogen (ammonia, nitrate, nitrite and TKN), chemical oxygen demand (COD), total suspended solids (TSS) ...

  20. Ecogenotoxicity testing of aquatic environment by comet assay in plants

    Directory of Open Access Journals (Sweden)

    Anita Mukherjee

    2015-05-01

    Full Text Available One of the goals of environmental monitoring is the detection of potentially hazardous compounds in water. We have set up a standard method to apply the Comet assay in aquatic plants that could be of great interest to evaluate cytotoxicity, genotoxicity and oxidative stress on the same species regarded as most sensitive to environmental pollutants. The aim of the present study was to set up of standardized procedure to evaluate genotoxicity in aquatic plants- Ceratophyllum demersum one that is submerged free floating and the other is Lemna minor - a fresh water floating plant by Comet assay. Electrophoresis and unwinding times were adapted to obtain minimum DNA migration evaluated as tail intensity % or tail moment in the control group and, at the same time maximum sensitivity for DNA damage with known genotoxicants. We further investigated the cytotoxicity and oxidative stress induced in the same species. Based on the repeatability of results obtained we suggest that Ceratophyllum, Lemna can serve as model species and Comet assay could be adopted to monitor the eco-genotoxicity of water pollutants.

  1. Kinesiological Analysis of Stationary Running Performed in Aquatic and Dry Land Environments

    Directory of Open Access Journals (Sweden)

    Lima Alberton Cristine

    2015-12-01

    Full Text Available The purpose of the present study was to analyze the electromyographic (EMG signals of the rectus femoris (RF, vastus lateralis (VL, semitendinosus (ST and short head of the biceps femoris (BF during the performance of stationary running at different intensities in aquatic and dry land environments. The sample consisted of 12 female volunteers who performed the stationary running exercise in aquatic and dry land environments at a submaximal cadence (80 beats·min-1 controlled by a metronome and at maximal velocity, with EMG signal measurements from the RF, VL, ST and BF muscles. The results showed a distinct pattern between environments for each muscle examined. For the submaximal cadence of 80 beats·min-1, there was a reduced magnitude of the EMG signal in the aquatic environment, except for the ST muscle, the pattern of which was similar in both environments. In contrast to the submaximal cadence, the pattern of the EMG signal from all of the muscles showed similar magnitudes for both environments and phases of movement at maximal velocity, except for the VL muscle. Therefore, the EMG signals from the RF, VL, ST and BF muscles of women during stationary running had different patterns of activation over the range of motion between aquatic and dry land environments for different intensities. Moreover, the neuromuscular responses of the lower limbs were optimized by an increase in intensity from submaximal cadence to maximal velocity.

  2. Biological Implications of Gene-Environment Interaction

    Science.gov (United States)

    Rutter, Michael

    2008-01-01

    Gene-environment interaction (G x E) has been treated as both a statistical phenomenon and a biological reality. It is argued that, although there are important statistical issues that need to be considered, the focus has to be on the biological implications of G x E. Four reports of G x E deriving from the Dunedin longitudinal study are used as…

  3. Monitoring aquatic environment pollution: a major component of environment management systems

    International Nuclear Information System (INIS)

    The paper is based on the international experiences mostly of the UK (United Kingdom) and Europe on monitoring aquatic pollution and controlling water pollution which have a long history of the legislation involved. The U.K. control of water pollution and regulatory laws are very effective as in shown by the fact that 96 percent of rivers in England and Wales are suitable for potable supplies with conventional water treatment. Current British legislation is basically contained n the 1951, 1960 and 1974 acts of parliament in the U.K. A common feature of all this environment legislation is the high level of consultation which has taken place between government and all concerned and al those concerned in the development of legislation and drawing up regulations etc. and involved in implementation of them. Similarly considerable discussion takes place with the controlling authorities by dischargers over the detailed implementation of legislation in the U.K. Consequently these harmonious attitudes have been responsible for the effectiveness of the U.K. legislation. In the U.K. control of discharges of industrial effluents to sewers and to all natural waters including underground water is vested in the regional water authorities, which on application, issue consent permitting discharges of industrial effluents to sewers and to all natural waters including underground waters in vested in the regional water authorities, which on application, issue consent permitting discharges to be made subject to conditions and limitations in the consent/authorisation/approval. The paper critically reviews major aspects of the philosophy of aquatic pollution control and monitoring, as statistics reveal deadly state of liquid effluent contamination water bodies in Pakistan. Without prompt installation of treatment plants we may face a tragedy of catastrophic magnitude. (author)

  4. Inorganic nanomaterials in the aquatic environment: behavior, toxicity, and interaction with environmental elements

    Directory of Open Access Journals (Sweden)

    Krzyżewska Iwona

    2016-03-01

    Full Text Available The aim of this paper is to present characteristics, toxicity and environmental behavior of nanoparticles (NPs (silver, copper, gold, zinc oxide, titanium dioxide, iron oxide that most frequently occur in consumer products. In addition, NPs are addressed as the new aquatic environmental pollutant of the 21st century. NPs are adsorbed onto particles in the aquatic systems (clay minerals, fulvic and humic acids, or they can adsorb environmental pollutants (heavy metal ions, organic compounds. Nanosilver (nAg is released from consumer products into the aquatic environment. It can threaten aquatic organisms with high toxicity. Interestingly, copper nanoparticles (Cu-NPs demonstrate higher toxicity to bacteria and aquatic microorganisms than those of nanosilver nAg. Their small size and reactivity can cause penetration into the tissues and interfere with the metabolic systems of living organisms and bacterial biogeochemical cycles. The behavior of NPs is not fully recognized. Nevertheless, it is known that NPs can agglomerate, bind with ions (chlorides, sulphates, phosphates or organic compounds. They can also be bound or immobilized by slurry. The NPs behavior depends on process conditions, i.e. pH, ionic strength, temperature and presence of other chemical compounds. It is unknown how NPs behave in the aquatic environment. Therefore, the research on this problem should be carried out under different process conditions. As for the toxicity, it is important to understand where the differences in the research results come from. As NPs have an impact on not only aquatic organisms but also human health and life, it is necessary to recognize their toxic doses and know standards/regulations that determine the permissible concentrations of NPs in the environment.

  5. Mercury Release to Aquatic Environments from Anthropogenic Sources in China from 2001 to 2012.

    Science.gov (United States)

    Liu, Maodian; Zhang, Wei; Wang, Xuejun; Chen, Long; Wang, Huanhuan; Luo, Yao; Zhang, Haoran; Shen, Huizhong; Tong, Yindong; Ou, Langbo; Xie, Han; Ye, Xuejie; Deng, Chunyan

    2016-08-01

    Based on an analysis of measured data and distribution factors, we developed the China Aquatic Mercury Release (CAMR) model, which we used to calculate an inventory of mercury (Hg) that was released to aquatic environments from primary anthropogenic sources in China. We estimated a total release of 98 tons of Hg in 2012, including coal-fired power plants (17%), nonferrous metal smelting (33%), coal mining and washing (25%), domestic sewage (17%), and other sectors (8.3%). The total primary anthropogenic Hg released to aquatic environments in China decreased at an annual average rate of 1.7% between 2001 and 2012, even though GDP grew at an annual average rate of 10% during this period. In addition to the Hg that was released to aquatic environments in China's provinces, we estimated the Hg release amounts and intensities (in g/km(2)·yr) for China's 58 secondary river basins. The highest aquatic Hg release intensities in China were associated with industrial wastewater on the North China Plain and domestic sewage in eastern China and southern China. We found that the overall uncertainty of our inventory ranges from -22% to 32%. We suggest that the inventory provided by this study can help establish a more accurate map of regional and global Hg cycling; it also has implications for water quality management in China. PMID:27379546

  6. Antibiotic resistance in urban aquatic environments: can it be controlled?

    OpenAIRE

    Manaia, Célia; Macedo, Gonçalo; Fatta-Kassinos, Despo; Nunes, Olga

    2016-01-01

    Over the last decade, numerous evidences have contributed to establish a link between the natural and humanimpacted environments and the growing public health threat that is the antimicrobial resistance. In the environment, in particular in areas subjected to strong anthropogenic pressures, water plays a major role on the transformation and transport of contaminants including antibiotic residues, antibioticresistant bacteria, and antibiotic resistance genes. Therefore, ...

  7. Fractionation, mobility and biological accessibility of radionuclides in the environment

    International Nuclear Information System (INIS)

    Fractionation of radionuclides is stipulated by varied distribution of certain isotopes on aerosol particles from nuclear explosions and accidents. The character of isotope distribution on the aerosol particles governs peculiarities of radionuclide distribution in the environments - the air, soil, surface and ground water and sea environment. Mobility of radionuclides after their fallout on the Earth's surface is determined by possibility of their contact with the aquatic environment and chemical properties of elements (or their compounds) in the form of which the radionuclides do exist. Biological accessibility is determined by mobility of radionuclides and their penetration into living organisms. The presentation discusses the degree of transition of radioactive isotopes of certain elements from the particles to the water and muriatic acid (and gastric juice); the dependence is highlighted between biological accessibility of radionuclides, the distance from an epicentre of an explosion or accident and characteristic features of particles - carriers of radioactivity. The processes of wash-off of radionuclides from soil to the water, vertical migration into the soil and their redistribution by surface and ground water are described. The use of wash-off coefficients, obtained by observation after nuclear explosions, provided a possibility to forecast already in May 1986 water contamination in rivers and storages in summer, 1986 and spring flood of 1987 in the zone of the Chernobyl accident. The paper demonstrates that the reliable data on fractionation and biological accessibility are needed to solve effectively the problems of rehabilitation of the zones contaminated after nuclear explosions and accidents. (author)

  8. Daphnia as a model organism in limnology and aquatic biology: introductory remarks

    OpenAIRE

    Petrusek, Adam; Jaromir SEDA

    2011-01-01

    Cladocerans of the genus Daphnia are keystone pelagic filter feeders in many temperate ponds and lakes. They have also become popular model organisms in various biological disciplines, from aquatic ecology to biomedical sciences. The crucial features that make these organisms excellent experimental models are their cyclical parthenogenetic life cycle together with easy culturing and handling. Thanks to these characteristics, the number of publications dealing with Daphnia is rapidly growing. ...

  9. Turnover of eroded soil organic carbon after deposition in terrestrial and aquatic environments

    DEFF Research Database (Denmark)

    Kirkels, Frédérique; Cammeraat, Erik; Kalbitz, Karsten;

    The fate of eroded soil organic carbon (SOC) after deposition is a large uncertainty in assessing the impact of soil erosion on C budgets. Globally, large amounts of SOC are transported by erosion and a substantial part is transferred into adjacent inland waters, linking terrestrial and aquatic C...... cycling. However, the net effect on C fluxes between soils, inland waters and atmosphere remains uncertain. In this study, we determined SOC turnover in terrestrial and aquatic environments and indentified its major controls. A European gradient of agricultural sites was sampled, spanning a wide range...... (soils vs. inland waters) play a crucial role in determining C turnover. Erosion measures preventing deposition in aquatic environments could therefore be an important carbon saving strategy. We envisage that these quantitative results can be used to parameterize biogeochemical models and contribute to...

  10. Are we going about chemical risk assessment for the aquatic environment the wrong way?

    Science.gov (United States)

    Johnson, Andrew C; Sumpter, John P

    2016-07-01

    The goal of protecting the aquatic environment through testing thousands of chemicals against hundreds of aquatic species with thousands of endpoints while also considering mixtures is impossible given the present resources. Much of the impetus for studies on micropollutants, such as pharmaceuticals, came from the topic of endocrine disruption in wild fish. But despite concern over reductions in fish fertility, there is little evidence that fish populations are in peril. Indeed, fish biologists suggest that many cyprinid populations have been recovering for the past 30 to 40 yr. The central assumption, key to current risk assessment, that effects observed in the laboratory or predicted by models are readily transferrable to the population level, is therefore questionable. The neglect in monitoring wildlife populations is the key weakness in environmental protection strategies. If we do not know whether aquatic wildlife species are declining or increasing, how valuable are our other ecotoxicological activities? Environ Toxicol Chem 2016;35:1609-1616. © 2016 SETAC. PMID:27331653

  11. Presence, fate and effects of the intense sweetener sucralose in the aquatic environment

    International Nuclear Information System (INIS)

    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

  12. 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

  13. Biological filter capable of simultaneous nitrification and denitrification for Aquatic Habitat in International Space Station

    Science.gov (United States)

    Uemoto, H.; Shoji, T.; Uchida, S.

    2014-04-01

    The biological filter capable of simultaneous nitrification and denitrification was constructed for aquatic animal experiments in the International Space Station (ISS). The biological filter will be used to remove harmful ammonia excreted from aquatic animals in a closed water circulation system (Aquatic Habitat). The biological filter is a cylindrical tank packed with porous glass beads for nitrification and dual plastic bags for denitrification. The porous beads are supporting media for Nitrosomonas europaea and Nitrobacter winogradskyi. The N. europaea cells and N. winogradskyi cells on the porous beads, oxidize the excreted ammonia to nitrate via nitrite. On the other hand, the dual bag is composed of an outer non-woven fabric bag and an inner non-porous polyethylene film bag. The outer bag is supporting media for Paracoccus pantotrophus. The inner bag, in which 99.5% ethanol is packed, releases the ethanol slowly, since ethanol can permeate through the non-porous polyethylene film. The P. pantotrophus cells on the outer bag reduce the produced nitrate to nitrogen gas by using the released ethanol as an electron donor for denitrification. The biological filter constructed in this study consequently removed the ammonia without accumulating nitrate. Most of the excess ethanol was consumed and did not affect the nitrification activity of the N. europaea cells and N. winogradskyi cells severely. In accordance with the aquatic animal experiments in the ISS, small freshwater fish had been bred in the closed water circulation system equipped with the biological filter for 90 days. Ammonia concentration daily excreted from fish is assumed to be 1.7 mg-N/L in the recirculation water. Under such conditions, the harmful ammonia and nitrite concentrations were kept below 0.1 mg-N/L in the recirculation water. Nitrate and total organic carbon concentrations in the recirculation water were kept below 5 mg-N/L and 3 mg-C/L, respectively. All breeding fish were alive and ate

  14. Methods for collection and analysis of aquatic biological and microbiological samples

    Science.gov (United States)

    Britton, L.J.; Greeson, P.E.

    1988-01-01

    Chapter A4, methods for collection and analyses of aquatic biological and microbiological samples, contains methods used by the U.S. Geological Survey to collect, preserve, and analyze waters to determine their biological and microbiological properties. Part 1 consists of detailed descriptions of more than 45 individual methods, including those for bacteria, phytoplankton, zooplankton, seston, periphyton, macrophytes, benthic invertebrates, fish and other vertebrates, cellular contents, productivity and bioassay. Each method is summarized, and the applications, interferences, apparatus, reagents, analyses, calculations, reporting of results, precisions, and references are given. Part 2 consists of a glossary. Part 3 is a list of taxonomic references. (USGS)

  15. A supplement to "Methods for collection and analysis of aquatic biological and microbiological samples"

    Science.gov (United States)

    1979-01-01

    The report contains methods used by the U.S. Geological Survey to collect, preserve, and analyze waters to determine their biological and microbiological properties. It supplements, "Methods for Collection and Analysis of Aquatic Biological and Microbiological Samples" (TWRI, Book 5, Chapter A4, 1977, edited by P. E. Greeson, T. A. Ehlke, G. A. Irwin, B. W. Lium, and K. V. Slack). Included in the supplement are 5 new methods, a new section of selected taxonomic references for Ostracoda, and 6 revised methods.

  16. Crude oil derived petroleum products in the aquatic environment: priorities for control

    International Nuclear Information System (INIS)

    The available data on the environmental fate, behaviour and toxicity of five groups of petroleum products is reviewed and the information used to identify the priority of oil products for pollution control to protect the aquatic environment. The oil product groups comprise gasolines, kerosenes, other light fuel oil distillates, residual heavy fuel oils and lubricating oils. (author)

  17. Potential Upstream Strategies for the Mitigation of Pharmaceuticals in the Aquatic Environment: a Brief Review.

    Science.gov (United States)

    Blair, Benjamin D

    2016-06-01

    Active pharmaceutical ingredients represent a class of pollutants of emerging concern, and there is growing evidence that these pollutants can cause damage to the aquatic environment. As regulations to address these concerns are expected in developed nations, decision-makers are looking to the scientific community for potential solutions. To inform these regulatory efforts, further information on the potential strategies to reduce the levels of pharmaceuticals entering the aquatic environment is needed. End-of-pipe (i.e., wastewater treatment) technologies that can remove pharmaceuticals exist; however, they are costly to install and operate. Thus, the goal of this brief review is to look beyond end-of-pipe solutions and present various upstream mitigation strategies discussed within the scientific literature. Programs such as pharmaceutical take-back programs currently exist to attempt to reduce pharmaceutical concentrations in the environment, although access and coverage are often limited for many programs. Other potential strategies include redesigning pharmaceuticals to minimize aquatic toxicity, increasing the percent of the pharmaceuticals metabolized in the body, selecting less harmful pharmaceuticals for use, starting new prescriptions at lower dosages, selecting pharmaceuticals with lower excretion rates, and implementing source treatment such as urine separating toilets. Overall, this brief review presents a summary of the upstream preventative recommendations to mitigate pharmaceuticals from entering the aquatic environment with an emphasis on regulatory efforts in the USA and concludes with priorities for further research. PMID:27068434

  18. NOVANA - National Monitoring and Assessment Programme for the Aquatic and Terrestrial Environment

    DEFF Research Database (Denmark)

    Svendsen, L. M.

    This report is Part 1 of the Programme Description of NOVANA - the Nationwide Monitoring and Assessment Programme for the Aquatic and Terrestrial Environments. Part 1 comprises a general description of the background for the programme, including the international obliga-tions and requirements...

  19. Antibiotic resistance in urban aquatic environments: can it be controlled?

    Science.gov (United States)

    Manaia, Célia M; Macedo, Gonçalo; Fatta-Kassinos, Despo; Nunes, Olga C

    2016-02-01

    Over the last decade, numerous evidences have contributed to establish a link between the natural and human-impacted environments and the growing public health threat that is the antimicrobial resistance. In the environment, in particular in areas subjected to strong anthropogenic pressures, water plays a major role on the transformation and transport of contaminants including antibiotic residues, antibiotic-resistant bacteria, and antibiotic resistance genes. Therefore, the urban water cycle, comprising water abstraction, disinfection, and distribution for human consumption, and the collection, treatment, and delivery of wastewater to the environment, is a particularly interesting loop to track the fate of antibiotic resistance in the environment and to assess the risks of its transmission back to humans. In this article, the relevance of different transepts of the urban water cycle on the potential enrichment and spread of antibiotic resistance is reviewed. According to this analysis, some gaps of knowledge, research needs, and control measures are suggested. The critical rationale behind the measures suggested and the desirable involvement of some key action players is also discussed. PMID:26649735

  20. Understanding the Water Crisis in China: Towards a Harmonious Aquatic Environment

    Institute of Scientific and Technical Information of China (English)

    SHI Jianbo; WANG Thanh; JIANG Guibin

    2011-01-01

    @@ China is one of the 13 countries in the world with the most limited water resources.With the fast economic development and urbanization in recent years, the demand of water is continuously increasing and severe water shortage has occurred.The situation is further exacerbated by unevenly distribution, low water use efficiency and serious contamination.As a result, wetland areas have decreased significantly and algal blooms occur more frequently, indicating increased deterioration of the aquatic ecosystem.In order to obtain a sustainable development, scientific utilization of water resources and protection of the aquatic environment are urgently needed.

  1. Mechanisms and pathways of aniline elimination from aquatic environments.

    OpenAIRE

    Lyons, C D; Katz, S; Bartha, R.

    1984-01-01

    The fate of aniline, a representative of arylamine pollutants derived from the manufacture of dyes, coal liquefaction, and pesticide degradation, was comprehensively evaluated by use of unpolluted and polluted pond water as model environments. Evaporation plus autoxidation proved to be minor elimination mechanisms, removing ca. 1% of the added aniline per day. Instantaneous binding to humic components of a 0.1% sewage sludge inoculum removed 4%. Biodegradation of aniline in pond water was acc...

  2. ACCUMULATION OF POLYCHLORINATED BIPHENYLS IN AQUATIC ORGANISMS AND ENVIRONMENT

    OpenAIRE

    ÇAKIROĞULLARI, Gül

    2010-01-01

    Polychlorinated biphenyls (PCBs) were discovered in the late of the 19th century and their usefulness for industry, because of their physical properties, was recognized early. The PCBs have been used commercially, since 1930, as dielectric and heat-exchange fluids and in a variety of other applications. They have become widely distributed in the environment throughout the world, and are persistent and accumulate in food webs. PCBs accumulate in the fatty tissues of humans and other animals an...

  3. Fate of artificial sweeteners and perfluoroalkyl acids in aquatic environment

    OpenAIRE

    Perkola, Noora

    2014-01-01

    The newly detected chemicals, the environmental distribution, fate, and effects in the environment of which are not well known, are called emerging compounds. Artificial sweeteners are one group of emerging compounds. The consumption of artificial sweeteners is high, and because they do not significantly metabolise, all that is consumed finds its way to wastewater treatment plants. Two artificial sweeteners, acesulfame and sucralose, do not degrade in wastewater treatment either, leading to e...

  4. Isolation of drug-resistant Aeromonas hydrophila from aquatic environments.

    OpenAIRE

    McNicol, L A; Aziz, K. M.; Huq, I; Kaper, J B; Lockman, H A; Remmers, E F; Spira, W M; Voll, M. J.; Colwell, R R

    1980-01-01

    Antibiotic-resistant strains of Aeromonas hydrophila have been isolated from the natural environment in the Chesapeake Bay and areas surrounding Dacca and the Matlab region of Bangladesh. The Bangladesh strains carried resistance to chloramphenicol, streptomycin, and tetracycline, and 57% of them had a multiple streptomycin-tetracycline resistance phenotype correlated with the presence of a large plasmid. The Chesapeake Bay strains were resistant to polymyxin B ane tetracycline, but showed ne...

  5. Priority and emerging flame retardants in the aquatic environment: analytical development, occurrence and risk

    OpenAIRE

    Cristale, Joyce

    2013-01-01

    [spa]The presence of priority and emerging flame retardants (FR) in the environment deserve attention since many of these substances are toxic and persistent. The aim of this thesis was to evaluate the occurrence and impact of priority and emerging flame retardants in the aquatic environment. To accomplish this main objective, the present thesis involved the development of multiresidue methods for the analysis of different FR families in water, sediment, dust and sewage sludge and the applica...

  6. Interactions of 238PuO2 heat sources with terrestrial and aquatic environments. Interim summary

    International Nuclear Information System (INIS)

    Observations and some conclusions made of the interactions of 238PuO2 heat sources with terrestrial and aquatic environments may be used in predicting heat source behavior in the event of contact of these heat sources with land or ocean and in assessing the risk to the environment. These studies indicate that plutonium transport from the heat sources is mostly a physical process involving the movement of extremely fine particles rather than the chemical migration of plutonium ions

  7. Azospirillum genomes reveal transition of bacteria from aquatic to terrestrial environments.

    Directory of Open Access Journals (Sweden)

    Florence Wisniewski-Dyé

    2011-12-01

    Full Text Available Fossil records indicate that life appeared in marine environments ∼3.5 billion years ago (Gyr and transitioned to terrestrial ecosystems nearly 2.5 Gyr. Sequence analysis suggests that "hydrobacteria" and "terrabacteria" might have diverged as early as 3 Gyr. Bacteria of the genus Azospirillum are associated with roots of terrestrial plants; however, virtually all their close relatives are aquatic. We obtained genome sequences of two Azospirillum species and analyzed their gene origins. While most Azospirillum house-keeping genes have orthologs in its close aquatic relatives, this lineage has obtained nearly half of its genome from terrestrial organisms. The majority of genes encoding functions critical for association with plants are among horizontally transferred genes. Our results show that transition of some aquatic bacteria to terrestrial habitats occurred much later than the suggested initial divergence of hydro- and terrabacterial clades. The birth of the genus Azospirillum approximately coincided with the emergence of vascular plants on land.

  8. Removal of cytostatic drugs from aquatic environment: a review.

    Science.gov (United States)

    Zhang, Jiefeng; Chang, Victor W C; Giannis, Apostolos; Wang, Jing-Yuan

    2013-02-15

    Cytostatic drugs have been widely used for chemotherapy for decades. However, many of them have been categorized as carcinogenic, mutagenic and teratogenic compounds, triggering widespread concerns about their occupational exposure and ecotoxicological risks to the environment. This review focuses on trace presence, fate and ecotoxicity of various cytostatic compounds in the environment, with an emphasis on the major sources contributing to their environmental concentrations. Past records have documented findings mainly on hospital effluents though little effort has been directed to household discharges. There is also a lack in physico-chemical data for forecasting the chemodynamics of cytostatics in natural waters along with its human metabolites and environmental transformation products. In this light, obtaining comprehensive ecotoxicity data is becoming pressingly crucial to determine their actual impacts on the ecosystem. Literature review also reveals urinary excretion as a major contributor to various cytostatic residues appeared in the water cycle. As such, engaging urine source-separation as a part of control strategy holds a rosy prospect of addressing the "emerging" contamination issue. State-of-the-art treatment technologies should be incorporated to further remove cytostatic residues from the source-separating urine stream. The benefits, limitations and trends of development in this domain are covered for membrane bio-reactor, reverse/forward osmosis and advanced oxidation processes. Despite the respective seeming advantages of source separation and treatment technology, a combined strategy may cost-effectively prevent the cytostatic residues from seeping into the environment. However, the combination calls for further evaluation on the associated technological, social-economic and administrative issues at hand. PMID:23337605

  9. Removal of cytostatic drugs from aquatic environment: A review

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jiefeng [Division of Environmental and Water Resources, School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Chang, Victor W.C., E-mail: wcchang@ntu.edu.sg [Division of Environmental and Water Resources, School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Giannis, Apostolos [Residues and Resource Reclamation Centre (R3C), Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore 637141 (Singapore); Wang, Jing-Yuan [Division of Environmental and Water Resources, School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Residues and Resource Reclamation Centre (R3C), Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore 637141 (Singapore)

    2013-02-15

    Cytostatic drugs have been widely used for chemotherapy for decades. However, many of them have been categorized as carcinogenic, mutagenic and teratogenic compounds, triggering widespread concerns about their occupational exposure and ecotoxicological risks to the environment. This review focuses on trace presence, fate and ecotoxicity of various cytostatic compounds in the environment, with an emphasis on the major sources contributing to their environmental concentrations. Past records have documented findings mainly on hospital effluents though little effort has been directed to household discharges. There is also a lack in physico-chemical data for forecasting the chemodynamics of cytostatics in natural waters along with its human metabolites and environmental transformation products. In this light, obtaining comprehensive ecotoxicity data is becoming pressingly crucial to determine their actual impacts on the ecosystem. Literature review also reveals urinary excretion as a major contributor to various cytostatic residues appeared in the water cycle. As such, engaging urine source-separation as a part of control strategy holds a rosy prospect of addressing the “emerging” contamination issue. State-of-the-art treatment technologies should be incorporated to further remove cytostatic residues from the source-separating urine stream. The benefits, limitations and trends of development in this domain are covered for membrane bio-reactor, reverse/forward osmosis and advanced oxidation processes. Despite the respective seeming advantages of source separation and treatment technology, a combined strategy may cost-effectively prevent the cytostatic residues from seeping into the environment. However, the combination calls for further evaluation on the associated technological, social-economic and administrative issues at hand. Highlights: ► We review the environmental occurrence, fate and ecotoxicity of cytostatic drugs. ► Four major sources contributing to

  10. Removal of cytostatic drugs from aquatic environment: A review

    International Nuclear Information System (INIS)

    Cytostatic drugs have been widely used for chemotherapy for decades. However, many of them have been categorized as carcinogenic, mutagenic and teratogenic compounds, triggering widespread concerns about their occupational exposure and ecotoxicological risks to the environment. This review focuses on trace presence, fate and ecotoxicity of various cytostatic compounds in the environment, with an emphasis on the major sources contributing to their environmental concentrations. Past records have documented findings mainly on hospital effluents though little effort has been directed to household discharges. There is also a lack in physico-chemical data for forecasting the chemodynamics of cytostatics in natural waters along with its human metabolites and environmental transformation products. In this light, obtaining comprehensive ecotoxicity data is becoming pressingly crucial to determine their actual impacts on the ecosystem. Literature review also reveals urinary excretion as a major contributor to various cytostatic residues appeared in the water cycle. As such, engaging urine source-separation as a part of control strategy holds a rosy prospect of addressing the “emerging” contamination issue. State-of-the-art treatment technologies should be incorporated to further remove cytostatic residues from the source-separating urine stream. The benefits, limitations and trends of development in this domain are covered for membrane bio-reactor, reverse/forward osmosis and advanced oxidation processes. Despite the respective seeming advantages of source separation and treatment technology, a combined strategy may cost-effectively prevent the cytostatic residues from seeping into the environment. However, the combination calls for further evaluation on the associated technological, social-economic and administrative issues at hand. Highlights: ► We review the environmental occurrence, fate and ecotoxicity of cytostatic drugs. ► Four major sources contributing to

  11. Organica micropollutants in the aquatic environment: identification of cationic surfactants

    International Nuclear Information System (INIS)

    The data (concentrations, pollution loads) measured for the 560 km flowing stretch of the river Elbe on the territory of the former GDR were compiled and evaluated according to primary statistical aspects. The longitudinal section was prepared for major variables with regard to the flow for Q50% and Q5%. The distribution of concentration in various measuring points was shown by means of box plots. Interdependencies between concentration and flow as well as water temperature were investigated and used for assessing diffuse matter input. In addition to determining the saprobic index, the biological control of water pollution comprised the assessment of the macrozoobenthos in the area of sewage discharge, chlorophyll measurements, an inventory of the fish population, analysis of pollutant accumulation in fish and in zoobenthos as well as virus detection. The water quality of the river Elbe was evaluated in compliance with the binding E.C. guidelines and national regulations/recommendations revealing an extreme pollution level which impairs or excludes various utilizations of the Elbe water. (orig.). 73 refs., 11 tabs., 48 figs

  12. Azole Fungicides as Synergists in the Aquatic Environment

    DEFF Research Database (Denmark)

    Bjergager, Maj-Britt Andersen

    reasonableapproach for non-interacting contaminants, synergizing compounds, enhancing the toxicity of others, maycompromise the predictive ability of the models. Though only rarely occurring, the phenomenon ofsynergism is of great concern, making apparently low and non-toxic contaminant concentrations apotential...... hazard.This PhD thesis evaluates the role of the so called azole fungicides as synergists in the aquaticenvironment through an assessment of the effect of sorption, time and azole concentration on theoccurrence and magnitude of synergistic interactions with pyrethroid insecticides towards the...... aquaticcrustacean Daphnia magna in both laboratory experiments and natural-like environments. In the PhDthesis, synergy is defined as happening in mixtures where either EC50 values decrease more than two-foldbelow the prediction by the model of Concentration Addition (horizontal assessment of synergy) or wherethe...

  13. Evaluation of removal efficiency of 2-chlorophenol in aquatic environments by modified fly ash

    OpenAIRE

    Mohammad Malakootian; Alireza Mesdaghinia; Shima Rezaei

    2015-01-01

    Background: Chlorophenols are classified as priority toxic pollutants. These acidic organic compounds present a serious potential hazard for human health and aquatic life. Chlorophenols accumulate in water, soil and air due to high stability, and impart an unpleasant taste and odor to drinking water and can exert negative effects on different biological processes. Among the different methods of removal, adsorption process by low price adsorbents, such as fly ash (FA) is common. Therefore, in ...

  14. Biogeochemistry of radionuclides in aquatic environments. Annual progress report, 1975--1976

    International Nuclear Information System (INIS)

    The present work is a combination of studies on natural radionuclides 210Po and 210Pb in aquatic environments and on the biogeochemistry of the transuranium elements 239Pu, 240Pu, and 241Am, in the Bikini Lagoon. The objectives of the biogeochemical studies are to evaluate the cycling of the radionuclides in the aquatic environment from their sources, their distribution within ecosystems, their uptake by biota, and their sinks. Detailed studies of the conditions which now exist some 17 years since the last nuclear detonations at Bikini should give a basis for predicting the effects of large-scale or low-level continuous releases of nuclear waste products in the marine environment

  15. Cesium-137 monitoring of aquatic and terrestrial environment in Goiania

    International Nuclear Information System (INIS)

    During the Goiania radiological accident, aprox. 1200 Ci of Cs - 137 were inadvertently manipulated and an unknown fraction of this total was available for environmental dispertion during at least 6 weeks, before efficient remedial action could be undertaken. The main dispersion pathways were rainwater run-off and soil ressuspension and further deposition. Cs-137 monitoring in the local environment started in the first week of October, including to date aprox. 1300 measurements of soil, vegetable (fruits and kitchen-gardens), ground and drinking water, sediments and fish, aerosol, precipitation and external dose measurement with TL dosimeters, in the surroundings of the main contamination spots. Until the conclusion of de-contamination activities in late December, the ranges of Cs-137 in a 50m radius of evacuated areas were as follows: 102-104 Bq/Kg for surface soils and edible vegetables, 100-101mBq/m3 in air and 10 Bq/l in all water types. River sediment and fish 5-10 Km downstream the accident are ranged respectively 102-103 and 102/Kg. These data indicated the pathways and locations for intervention for further reduction of radiation exposure. This intervention consisted mainly in tree-tipping and surface soil removal. (author)

  16. Application of vascular aquatic plants for pollution removal, energy and food production in a biological system

    Science.gov (United States)

    Wolverton, B. C.; Barlow, R. M.; Mcdonald, R. C.

    1975-01-01

    Vascular aquatic plants such as water hyacinths (Eichhornia crassipes) (Mart.) Solms and alligator weeds (Alternanthera philoxeroides) (Mart.) Griesb., when utilized in a controlled biological system (including a regular program of harvesting to achieve maximum growth and pollution removal efficiency), may represent a remarkably efficient and inexpensive filtration and disposal system for toxic materials and sewage released into waters near urban and industrial areas. The harvested and processed plant materials are sources of energy, fertilizer, animal feed, and human food. Such a system has industrial, municipal, and agricultural applications.

  17. Bioremediation of Heavy Metals from Soil and Aquatic Environment: An Overview of Principles and Criteria of Fundamental Processes

    Directory of Open Access Journals (Sweden)

    Ruchita Dixit

    2015-02-01

    Full Text Available Heavy metals are natural constituents of the environment, but indiscriminate use for human purposes has altered their geochemical cycles and biochemical balance. This results in excess release of heavy metals such as cadmium, copper, lead, nickel, zinc etc. into natural resources like the soil and aquatic environments. Prolonged exposure and higher accumulation of such heavy metals can have deleterious health effects on human life and aquatic biota. The role of microorganisms and plants in biotransformation of heavy metals into nontoxic forms is well-documented, and understanding the molecular mechanism of metal accumulation has numerous biotechnological implications for bioremediation of metal-contaminated sites. In view of this, the present review investigates the abilities of microorganisms and plants in terms of tolerance and degradation of heavy metals. Also, advances in bioremediation technologies and strategies to explore these immense and valuable biological resources for bioremediation are discussed. An assessment of the current status of technology deployment and suggestions for future bioremediation research has also been included. Finally, there is a discussion of the genetic and molecular basis of metal tolerance in microbes, with special reference to the genomics of heavy metal accumulator plants and the identification of functional genes involved in tolerance and detoxification.

  18. Impact on the aquatic environment of hydro-peaking in hydroelectric plants

    International Nuclear Information System (INIS)

    There are a number of types of hydroelectric installations on French rivers. Some of these intermittently turbine water stored in dammed reservoirs, in order to use available reserves at the most opportune moment for power generation. These plants, run under 'hydro-peaking' management procedures, cause variations in discharge in river sections downstream of the restitution, on a daily or weekly scale. To answer questions concerning the impact of such variations in discharge on the aquatic environment, EDF launched a research program aimed at describing and better understanding the physical and biological phenomena related to hydro-peaking and assessing the possible impact of this type of plant management on French streams. Seven sites subjects to hydro-peaking were studied on rivers with mean flow rates lower than 20 m3/s (which corresponds to over 65 % of EDF hydro-peaking sites). Four themes in particular were examined: hydraulic characterization of hydro-peaking, modifications in thermal regime and water quality, response of benthic invertebrates and response of fish populations to hydro-peaking. For fish as well as for invertebrates, the role of the base discharge - in the absence of peaking flow - and that of the morphology of the river bed (and, in particular, the presence of shelter for fish) during periods of strong discharge were clearly highlighted. Impact assessment requires a precise diagnosis of the state of biocenoses. To carry out such a diagnosis, one must reason in terms of species, life phase (particularly the most sensitive phases) and population structure as well as the type of stream and the faunizone involved. A risk assessment is possible by means of simultaneous study of the morphology of the river bed and the response of the signal generated by hydro-peaking in terms of hydrology and physical characteristics downstream of the restitution. (authors)

  19. Medicinal Water? The occurrence and fate of pharmaceuticals in aquatic environments A short communication

    OpenAIRE

    Ricardo Sánchez-Murillo

    2016-01-01

    Although very little is known about the transport, fate and toxic effects of medical compounds in aquatic environments, the presence of these compounds in potable water sources can no longer be overlooked. We can argue that trace concentrations of drugs in the water is relatively a minor problem, however, the current and future demands on global potable freshwater supplies will probably lead to greater incidents of indirect and direct water-reuse situations at the local, regional, and cr...

  20. Azospirillum genomes reveal transition of bacteria from aquatic to terrestrial environments.

    OpenAIRE

    Florence Wisniewski-Dyé; Kirill Borziak; Gurusahai Khalsa-Moyers; Gladys Alexandre; Sukharnikov, Leonid O.; Kristin Wuichet; Gregory B Hurst; W Hayes McDonald; Robertson, Jon S.; Valérie Barbe; Alexandra Calteau; Zoé Rouy; Sophie Mangenot; Claire Prigent-Combaret; Philippe Normand

    2011-01-01

    International audience Fossil records indicate that life appeared in marine environments ∼3.5 billion years ago (Gyr) and transitioned to terrestrial ecosystems nearly 2.5 Gyr. Sequence analysis suggests that "hydrobacteria" and "terrabacteria" might have diverged as early as 3 Gyr. Bacteria of the genus Azospirillum are associated with roots of terrestrial plants; however, virtually all their close relatives are aquatic. We obtained genome sequences of two Azospirillum species and analyze...

  1. Removal of inorganic mercury from aquatic environments by multi-walled carbon nanotubes

    OpenAIRE

    Yaghmaeian, Kamyar; Khosravi Mashizi, Reza; Nasseri, Simin; Mahvi, Amir Hossein; Alimohammadi, Mahmood; Nazmara, Shahrokh

    2015-01-01

    Background Mercury is considered as a toxic heavy metal in aquatic environments due to accumulation in bodies of living organisms. Exposure to mercury may lead to different toxic effects in humans including damages to kidneys and nervous system. Materials and methods Multi-walled carbon nanotubes (MWCNTs) were selected as sorbent to remove mercury from aqueous solution using batch technique. ICP instrument was used to determine the amount of mercury in solution. Moreover, pH, contact time and...

  2. Progestagens for human use. Exposure and hazard assessment for the aquatic environment

    OpenAIRE

    Besse, J.P.; Garric, J.

    2009-01-01

    Little information is available on the environmental occurrence and ecotoxicological effects of pharmaceutical gestagens released in the aquatic environment. Since eighteen different gestagens were found to be used in France, preliminary exposure and hazard assessment were done. Predicted environmental concentrations (PECs) suggest that if parent gestagens are expected to be found in the ng l−1 range, some active metabolites could be present at higher concentrations, although limited da...

  3. Natural and active chemical remediation of toxic metals, organics, and radionuclides in the aquatic environment

    Energy Technology Data Exchange (ETDEWEB)

    McPherson, G.; Pintauro, P.; O`Connor, S. [and others

    1996-05-02

    This project focuses on the chemical aspects of remediation, with the underlying theme that chemical remediation does occur naturally. Included are studies on the fate of heavy metal and organic contaminants discharged into aquatic environments; accurate assay metal contaminants partitioned into soils, water and tissue; development of novel polymeric membranes and microporous solids for the entrapment of heavy metals; and the development of hybrid chemo-enzymatic oxidative schemes for aromatics decontamination. 49 refs.

  4. Azospirillum Genomes Reveal Transition of Bacteria from Aquatic to Terrestrial Environments

    OpenAIRE

    Wisniewski-Dye, Florence; Borziak, Kirill; Khalsa-Moyers, Gurusahai; Alexandre, Gladys; O.Sukharnikov, Leonid; Wuichet, Kristin; B. Hurst, Gregory; Hayes Mcdonald, W.; S. Robertson, Jon; Barbe, Valerie; Calteau, Alexandra; Rouy, Zoe; Mangenot, Sophie; Prigent-Combaret, Claire; Normand, Philippe

    2011-01-01

    Fossil records indicate that life appeared in marine environments ∼3.5 billion years ago (Gyr) and transitioned to terrestrial ecosystems nearly 2.5 Gyr. Sequence analysis suggests that "hydrobacteria" and "terrabacteria" might have diverged as early as 3 Gyr. Bacteria of the genus Azospirillum are associated with roots of terrestrial plants; however, virtually all their close relatives are aquatic. We obtained genome sequences of two Azospirillum species and analyzed their gene origins. Whil...

  5. Revisiting the concept of recalcitrance and organic matter persistence in soils and aquatic systems: Does environment trump chemistry?

    Science.gov (United States)

    Marin-Spiotta, E.

    2014-12-01

    Most ecological models of decomposition rely on plant litter chemistry. However, growing evidence suggests that the chemical composition of organic matter (OM) is not a good predictor of its eventual fate in terrestrial or aquatic environments. New data on variable decomposition rates of select organic compounds challenge concepts of chemical recalcitrance, i.e. the inherent ability of certain molecular structures to resist biodegradation. The role of environmental or "ecosystem" properties on influencing decomposition dates back to some of the earliest research on soil OM. Despite early recognition that the physical and aqueous matrices are critical in determining the fate of organic compounds, the prevailing paradigm hinges on intrinsic chemical properties as principal predictors of decay rate. Here I build upon recent reviews and discuss new findings that contribute to three major transformations in our understanding of OM persistence: (1) a shift away from an emphasis on chemical recalcitrance as a primary predictor of turnover, (2) new interpretations of radiocarbon ages which challenge predictions of reactivity, and (3) the recognition that most detrital OM accumulating in soils and in water has been microbially processed. Predictions of OM persistence due to aromaticity are challenged by high variability in lignin and black C turnover observed in terrestrial and aquatic environments. Contradictions in the behavior of lignin are, in part, influenced by inconsistent methodologies among research communities. Even black C, long considered to be one of the most recalcitrant components of OM, is susceptible to biodegradation, challenging predictions of the stability of aromatic structures. At the same time, revised interpretations of radiocarbon data suggest that organic compounds can acquire long mean residence times by various mechanisms independent of their molecular structure. Understanding interactions between environmental conditions and biological

  6. Diversity and Impact of Prokaryotic Toxins on Aquatic Environments: A Review

    Directory of Open Access Journals (Sweden)

    Rogério Tenreiro

    2010-10-01

    Full Text Available Microorganisms are ubiquitous in all habitats and are recognized by their metabolic versatility and ability to produce many bioactive compounds, including toxins. Some of the most common toxins present in water are produced by several cyanobacterial species. As a result, their blooms create major threats to animal and human health, tourism, recreation and aquaculture. Quite a few cyanobacterial toxins have been described, including hepatotoxins, neurotoxins, cytotoxins and dermatotoxins. These toxins are secondary metabolites, presenting a vast diversity of structures and variants. Most of cyanobacterial secondary metabolites are peptides or have peptidic substructures and are assumed to be synthesized by non-ribosomal peptide synthesis (NRPS, involving peptide synthetases, or NRPS/PKS, involving peptide synthetases and polyketide synthases hybrid pathways. Besides cyanobacteria, other bacteria associated with aquatic environments are recognized as significant toxin producers, representing important issues in food safety, public health, and human and animal well being. Vibrio species are one of the most representative groups of aquatic toxin producers, commonly associated with seafood-born infections. Some enterotoxins and hemolysins have been identified as fundamental for V. cholerae and V. vulnificus pathogenesis, but there is evidence for the existence of other potential toxins. Campylobacter spp. and Escherichia coli are also water contaminants and are able to produce important toxins after infecting their hosts. Other bacteria associated with aquatic environments are emerging as toxin producers, namely Legionella pneumophila and Aeromonas hydrophila, described as responsible for the synthesis of several exotoxins, enterotoxins and cytotoxins. Furthermore, several Clostridium species can produce potent neurotoxins. Although not considered aquatic microorganisms, they are ubiquitous in the environment and can easily contaminate drinking

  7. Diversity and impact of prokaryotic toxins on aquatic environments: a review.

    Science.gov (United States)

    Valério, Elisabete; Chaves, Sandra; Tenreiro, Rogério

    2010-10-01

    Microorganisms are ubiquitous in all habitats and are recognized by their metabolic versatility and ability to produce many bioactive compounds, including toxins. Some of the most common toxins present in water are produced by several cyanobacterial species. As a result, their blooms create major threats to animal and human health, tourism, recreation and aquaculture. Quite a few cyanobacterial toxins have been described, including hepatotoxins, neurotoxins, cytotoxins and dermatotoxins. These toxins are secondary metabolites, presenting a vast diversity of structures and variants. Most of cyanobacterial secondary metabolites are peptides or have peptidic substructures and are assumed to be synthesized by non-ribosomal peptide synthesis (NRPS), involving peptide synthetases, or NRPS/PKS, involving peptide synthetases and polyketide synthases hybrid pathways. Besides cyanobacteria, other bacteria associated with aquatic environments are recognized as significant toxin producers, representing important issues in food safety, public health, and human and animal well being. Vibrio species are one of the most representative groups of aquatic toxin producers, commonly associated with seafood-born infections. Some enterotoxins and hemolysins have been identified as fundamental for V. cholerae and V. vulnificus pathogenesis, but there is evidence for the existence of other potential toxins. Campylobacter spp. and Escherichia coli are also water contaminants and are able to produce important toxins after infecting their hosts. Other bacteria associated with aquatic environments are emerging as toxin producers, namely Legionella pneumophila and Aeromonas hydrophila, described as responsible for the synthesis of several exotoxins, enterotoxins and cytotoxins. Furthermore, several Clostridium species can produce potent neurotoxins. Although not considered aquatic microorganisms, they are ubiquitous in the environment and can easily contaminate drinking and irrigation water

  8. Biologically Qualified Environment, Ecologically Evaluated Conditions

    Directory of Open Access Journals (Sweden)

    Judit Németh-Katona

    2008-06-01

    Full Text Available The biological quality of an environment is defined as the condition reflecting thequantitative representation of living organisms in a given space and time. My lecturepresents how to qualify the environment of a biocenosis synbiologically, in other words, onthe supraindividual level. In this case, qualifying the environment in practice means thatboth the quantitative and qualitative composition of the biocenosis, and also the factorsresponsible for their distribution in space and time are considered and evaluated ascharacteristics. The ultimate goal of examining conditions is to evaluate, in other words, todetermine relevancy and significance in a given biocenosis. We are facing the problem thatin Hungary at present the biological survey methods are not standardized, and they arehighly varied. An environmental information system however cannot function beforeappropriate methods of biological survey are created. The lack of such methods wouldresult that one of the three major, organically complementary sources of information (i.e.the abiotic sphere, the biosphere, and human society is completely missing. From adifferent aspect, ecological survey studies are different from the rest of environmentalsurvey studies, inasmuch as they study living organisms and their communities, thusinevitably utilizing the results of other environmental survey studies that evaluate differentcomponents. This indicates that the ecological section of all environmental survey studies isvitally important due to its complexity, and should be considered primarily decisive.

  9. Turnover of eroded soil organic carbon after deposition in terrestrial and aquatic environments

    Science.gov (United States)

    Kirkels, Frédérique; Cammeraat, Erik; Kalbitz, Karsten; van Oost, Kristof; Ellerbrock, Ruth; Follain, Stéphane; Fuchslueger, Lucia; Gerke, Horst; Heckrath, Goswin; Kögel-Knabner, Ingrid; Kuhn, Nikolaus; van Loon, Emiel; Quinton, John; Richter, Andreas; Salvador-Blanes, Sébastien; Sommer, Michael; Steffens, Markus

    2015-04-01

    The fate of eroded soil organic carbon (SOC) after deposition is a large uncertainty in assessing the impact of soil erosion on C budgets. Globally, large amounts of SOC are transported by erosion and a substantial part is transferred into adjacent inland waters, linking terrestrial and aquatic C cycling. However, the net effect on C fluxes between soils, inland waters and atmosphere remains uncertain. In this study, we determined SOC turnover in terrestrial and aquatic environments and indentified its major controls. A European gradient of agricultural sites was sampled, spanning a wide range soil properties (e.g. texture, aggregation, etc.), SOC quantity and quality. In a 16-week incubation experiment, SOC turnover was determined for conditions reflecting downslope soils or inland waters. Moreover, we studied the impact of labile C inputs ('priming') on SOC stability using 13C labeled cellulose. Physical and chemical soil properties and SOC molecular composition were assessed as potential controls on C turnover. SOC deposition in aquatic environments resulted in upto 3.5 times higher C turnover than deposition on downslope soils. Labile C inputs enlarged total CO2 emissions, with the largest increase for aquatic conditions. Solid-state 13C NMR and FT-IR spectroscopy showed broad similarities in SOC molecular composition. Soil and SOC properties could not (yet) fully explain variation in SOC turnover between the sites. However, temporal trends in CO2 emissions clearly differed between downslope soils and inland waters. We established a quantitative model, based on the ten sites of the European gradient, that is capable to describe CO2 emissions for SOC deposited on soils and in inland waters and upon different levels of labile C inputs. Our findings indicate that deposition conditions (soils vs. inland waters) play a crucial role in determining C turnover. Erosion measures preventing deposition in aquatic environments could therefore be an important carbon saving

  10. Fish otoliths as archives of metal concentrations in the aquatic environment

    International Nuclear Information System (INIS)

    Full text: Little is known of the relationship between the concentrations of metals in the laminations of the fish otolith and that in the environment. It is imperative that a concentration response relationship be demonstrated if otoliths are to be used as archives of metal concentrations in the aquatic environment. The aim of this preliminary study was to determine if there was an increase in concentration of Mn in the laminations of the fish otolith when fish were exposed to an elevated level of this metal. SIMS was used to measure Mn in the otolith. The findings will be discussed

  11. Occurrence of anionic surfactants in treated sewage: Risk assessment to aquatic environment

    Energy Technology Data Exchange (ETDEWEB)

    Mungray, Arvind Kumar [Department of Chemical Engineering, S.V. National Institute of Technology, Surat 395007 (India)], E-mail: akm@ched.svnit.ac.in; Kumar, Pradeep [Department of Civil Engineering, Indian Institute of Technology Roorkee, Roorkee 247667 (India)], E-mail: pkumafce@iitr.ernet.in

    2008-12-30

    A comparative evaluation of occurrence of and risk to aquatic environment due to anionic surfactants (AS) in treated effluents from three main treatment processes, i.e. activated sludge process (ASP), oxidation pond (OP), and upflow anaerobic sludge blanket reactor (UASBR) is presented. UASBR effluents contained substantial concentrations of AS (4.25-5.91 mg/L as average AS removal was not found to exceed 18%). Post-treatment of UASBR effluent using 1-1.6 days detention, anaerobic polishing ponds (PP) was also found quite ineffective. In UASBR-PP combine, AS reduced only up to 30%. Effluents from OP based sewage treatment plants (STPs) also contained significant concentrations of AS. On the contrary, effluent AS or linear alkylbenzene sulfonate (LAS) concentrations recorded in ASP effluents were quite low (less than 0.2 mg/L). Unlike UASBR, LAS or AS removals greater than 99% are achieved in ASP. Treated effluents from UASBR and OP based STPs when discharged to aquatic ecosystems are likely to cause substantial risk to aquatic environment due to the presence of AS while effluents from ASP are not supposed to pose risk. Need to find an effective aerobic post-treatment unit to UASBR for desired removal of AS is emphasized.

  12. Occurrence of anionic surfactants in treated sewage: Risk assessment to aquatic environment

    International Nuclear Information System (INIS)

    A comparative evaluation of occurrence of and risk to aquatic environment due to anionic surfactants (AS) in treated effluents from three main treatment processes, i.e. activated sludge process (ASP), oxidation pond (OP), and upflow anaerobic sludge blanket reactor (UASBR) is presented. UASBR effluents contained substantial concentrations of AS (4.25-5.91 mg/L as average AS removal was not found to exceed 18%). Post-treatment of UASBR effluent using 1-1.6 days detention, anaerobic polishing ponds (PP) was also found quite ineffective. In UASBR-PP combine, AS reduced only up to 30%. Effluents from OP based sewage treatment plants (STPs) also contained significant concentrations of AS. On the contrary, effluent AS or linear alkylbenzene sulfonate (LAS) concentrations recorded in ASP effluents were quite low (less than 0.2 mg/L). Unlike UASBR, LAS or AS removals greater than 99% are achieved in ASP. Treated effluents from UASBR and OP based STPs when discharged to aquatic ecosystems are likely to cause substantial risk to aquatic environment due to the presence of AS while effluents from ASP are not supposed to pose risk. Need to find an effective aerobic post-treatment unit to UASBR for desired removal of AS is emphasized

  13. Transfer of radionuclides at the uranium and thorium decay chains in aquatic and terrestrial environments

    International Nuclear Information System (INIS)

    This report examines the transfer of radionuclides from the uranium and thorium decay chains (U-238, Ra-226, Th-232, Th-230, Po-210 and Pb-210) through the aquatic and terrestrial environment. This transfer is characterized by a transfer coefficient; environmental and experimental factors which cause this coefficient to vary are presented and discussed in this report. Furthermore, based on a literature survey, the report indicates the range of coefficients found for the aquatic sector (that is, sediment and freshwater and marine organisms) and for the terrestrial sector (that is, plants and domestic and wild animals). Afterwards, generalisations are formulated on the transfer of the different radionuclides through the multiple environmental compartments. 75 refs

  14. The Chernobyl reactor accident and the aquatic environment of the UK: a fisheries viewpoint

    International Nuclear Information System (INIS)

    The monitoring programme undertaken by the Directorate throughout the UK following the Chernobyl reactor accident is described. The results of sampling and analysis of fish, shellfish, seaweed and other materials are discussed. Chernobyl fallout was readily detected in all sectors of the aquatic environment, particularly during May when the highest concentrations were observed. An assessment of the radiological impact of the fallout shows that freshwater fish were the most important source of individual (critical group) exposure though, based on cautious assumptions, the effective dose equivalent is around 1 mSv in a year. The collective effective dose equivalent commitment from Chernobyl due to aquatic ingestion pathways, predominantly marine fish, is estimated to be 30 man Sv. (author)

  15. Extracellular enzyme activities of aquatic bacteria in polluted environment: 1. Proteolytic activity

    International Nuclear Information System (INIS)

    Proteolytic activity (PA) of heterotrophic aquatic bacteria from differently polluted lakes was tested. Lake Dringis located in the Aukstaitija National Park was selected as an ecosystem that exhibits a low degree of impact by human activity, whereas Lake Druksiai was selected as being a chronically polluted water body. Industrial and residential waste flows into Lake Druksiai, the Ignalina Nuclear Power Plant cooling reservoir, via its tributaries (URS-2, MS and IRS-1.2). The PA of the lakes was found to be different. The total mean PA of Lake Dringis bacteria was 2.5 to 16 times greater than that from Lake Druksiai tributaries, URS-2, MS and IRS-1.2 and their mouths. Thus, the research showed that the PA of aquatic bacteria is related with the ecological state of the environment. Toxic materials entering the hydro ecosystem with industrial and residential waste waters exert a negative impact on the PA of heterotrophic bacteria. (author)

  16. Aquatic microphylla Azolla: a perspective paradigm for sustainable agriculture, environment and global climate change.

    Science.gov (United States)

    Kollah, Bharati; Patra, Ashok Kumar; Mohanty, Santosh Ranjan

    2016-03-01

    This review addresses the perspectives of Azolla as a multifaceted aquatic resource to ensure ecosystem sustainability. Nitrogen fixing potential of cyanobacterial symbiont varies between 30 and 60 kg N ha(-1) which designates Azolla as an important biological N source for agriculture and animal industry. Azolla exhibits high bioremediation potential for Cd, Cr, Cu, and Zn. Azolla mitigates greenhouse gas emission from agriculture. In flooded rice ecosystem, Azolla dual cropping decreased CH4 emission by 40 % than did urea alone and also stimulated CH4 oxidation. This review highlighted integrated approach using Azolla that offers enormous public health, environmental, and cost benefits. PMID:26697861

  17. Bioavailability and bioaccumulation of metal-based engineered nanomaterials in aquatic environments: concepts and processes: chapter 5

    Science.gov (United States)

    Luoma, Samuel N.; Khan, Farhan R.; Croteau, Marie-Noële

    2014-01-01

    Bioavailability of Me-ENMs to aquatic organisms links their release into the environment to ecological implications. Close examination shows some important differences in the conceptual models that define bioavailability for metals and Me-ENMs. Metals are delivered to aquatic animals from Me-ENMs via water, ingestion, and incidental surface exposure. Both metal released from the Me-ENM and uptake of the nanoparticle itself contribute to bioaccumulation. Some mechanisms of toxicity and some of the metrics describing exposure may differ from metals alone. Bioavailability is driven by complex interaction of particle attributes, environmental transformations, and biological traits. Characterization of Me-ENMs is an essential part of understanding bioavailability and requires novel methodologies. The relative importance of the array of processes that could affect Me-ENM bioavailability remains poorly known, but new approaches and models are developing rapidly. Enough is known, however, to conclude that traditional approaches to exposure assessment for metals would not be adequate to assess risks from Me-ENMs.

  18. Studies on radioactivity in aquatic and atmospheric environs of coastal Karnataka, Kaiga and Goa

    International Nuclear Information System (INIS)

    A systematic study on background radiation level and radionuclide distribution in the environs of coastal Karnataka, Kaiga and Goa has been initiated. In the first phase, a reliable baseline data on background radiation level and distribution of radionuclides in the terrestrial environs of coastal Karnataka and Kaiga was established. Investigations for establishing baseline data in aquatic and atmospheric environs of coastal Karnataka and terrestrial environs of Goa is now under progress. Atmospheric radon daughter concentrations, diurnal variations, seasonal variations and radon emanation rates are studied. A new approach to the model based on diffusion theory is formulated to understand 222Rn migration in soil. Experimental results are analysed on the basis of the new model and interpreted. The results of these systematic investigations are presented and discussed. (author)

  19. Aquatic plants

    DEFF Research Database (Denmark)

    Madsen, T. V.; Sand-Jensen, K.

    2006-01-01

    Aquatic fl owering plants form a relatively young plant group on an evolutionary timescale. The group has developed over the past 80 million years from terrestrial fl owering plants that re-colonised the aquatic environment after 60-100 million years on land. The exchange of species between...... terrestrial and aquatic environments continues today and is very intensive along stream banks. In this chapter we describe the physical and chemical barriers to the exchange of plants between land and water....

  20. Biological effects benchmarks for the protection of aquatic organisms against radiation

    International Nuclear Information System (INIS)

    In Canada, regulations developed under the Nuclear Safety Control Act require that license applicants describe the effects on the environment of the nuclear facility to be licensed. For the purpose of assessing risks to the environment the Canadian Nuclear Safety Commission recommends the use of an ecological risk assessment approach. It is based on toxicity benchmarks from chronic exposure studies of reproduction and survival in sensitive species. The benchmarks or Estimated No Effect Values (ENEVs) for the various taxonomic groups are determined from literature data using an ecotoxicological approach. The ENEVs derived for radiation effects on aquatic biota are: 0.6 mGyxd-1 for fish, 2 mGyxd-1 for amphibians and reptiles, 2.4 mGyxd-1 for algae and macrophytes and 4.6 mGyxd-1 for benthic invertebrates. (author)

  1. Using sediment cores to establish targets for the remediation of aquatic environments.

    Science.gov (United States)

    Lintern, Anna; Anderson, Marion; Leahy, Paul; Deletic, Ana; McCarthy, David

    2016-01-01

    When assigning site-specific restoration targets for deteriorating aquatic systems, it is necessary to have an understanding of the undisturbed or background state of the system. However, the site-specific characteristics of aquatic systems prior to disturbance are mostly unknown, due to the lack of historical water and sediment quality data. This study aims to introduce a method for filling this gap in our understanding, using dated sediment cores from the beds of aquatic environments. We used Bolin Billabong, a floodplain lake of the Yarra River (South-East Australia), as a case study to demonstrate the application of this method. We identified the concentrations of aluminium, cadmium, chromium, copper, iron, lead, manganese, nickel, tin and zinc at 8 cm intervals through the sediment core. This showed that aluminium, chromium, copper, iron, lead, nickel, tin and zinc concentrations in Bolin Billabong sediments significantly increased after European settlement in the river catchment in the mid-19th century. The differences between current Australian sediment quality guidelines trigger values and the background metal concentrations in Bolin Billabong sediments underscore the value of using locally relevant background toxicant concentrations when setting water and sediment quality targets. PMID:26877046

  2. The Impact of Mining Activity upon the Aquatic Environment in the Southern Apuseni Mountains

    Directory of Open Access Journals (Sweden)

    SIGISMUND DUMA

    2009-01-01

    Full Text Available In the Southern Apuseni Mountains, mining activities have taken place since Antiquity, leaving their marks upon the natural environment, the aquatic one inclusively. If the traditional technologies had a low impact upon the aquatic environment, the ones in the modern period have affected it up to the “dead water” level. It is about the disorganization of the hydrographical basins and especially about aggressive pollution of surface waters with some of the most toxic chemical substances such as cyanides, as well as by an increase in the contents of metallic ions, chlorides, sulphides, sulphates, suspensions and fixed residuum. The decrease in pH, and implicitly the acidification of waters, is also remarkable. It must be mentioned that no systematic studies of the impact of mining activities upon the aquatic environment have been conducted in the area in the last years. In these conditions, the data about water quality have been taken over from the studies conducted by author between 1996 and 1998. The cause of the lack of concern in the field is no other but the cease in ore valorization activities in the majority of the mining objectives in the area. As none of the tailings settling ponds has guard canals, the direct pluvial waters and the ones drained from the slopes transport tailings with noxes which they subsequently discharge in the local pluvial network. In these conditions, both the quality of the mine waters which run freely into the emissary and of the ones that flow from the waste dumps remain mainly in the qualitative parameters analyzed and presented in the study.

  3. Probing the fate of soil-derived core and intact polar GDGTs in aquatic environments

    Directory of Open Access Journals (Sweden)

    F. Peterse

    2014-07-01

    Full Text Available We have performed incubation experiments in order to examine the fate of branched glycerol dialkyl glycerol tetraether (brGDGT membrane lipids upon entering an aquatic environment and to asses the suitability of brGDGTs as tracers for fluvial land-sea transport of soil organic carbon. We incubated a soil from the Rakaia River catchment on the South Island of New Zealand using Rakaia River water and ocean water collected near the river mouth as inocula for a period of up to 152 days. The concentrations of brGDGTs derived from intact polar ("living"; IPL lipids and core ("fossil"; CL lipids remained stable over the course of the experiment, suggesting an absence of significant brGDGT production or degradation. Moreover, the lack of change in brGDGT distribution during the experiment implies that the initial soil signature remains unaltered during transport through the aquatic environment, at least over the time frame of the experiment. In contrast, the total pool of isoprenoid GDGTs (isoGDGTs, currently attributed to soil Thaumachaeota, increased substantially (27–72% in all incubation setups by the end of the experiment. As a consequence, a decrease in Branched and Isoprenoid Tetraether (BIT index values – a proxy for the relative input of fluvially discharged soil material into a marine system – became evident after an incubation period of 30 days, with a maximum final decrease of 0.88 to 0.74 in the experiment with river water. The relative distribution within the isoGDGT pool shows changes with time, suggesting different membrane adaptation rates to the aquatic environment, or a shift in source organism(s. While the stability of soil brGDGTs in aquatic environments reinforces their potential as tracers for land-sea transport of soil organic carbon and their use in paleoclimate reconstructions, the distributional differences between GDGTs in river water and nearby soil indicate that further research is needed to pinpoint the sources of

  4. Probing the fate of soil-derived core and intact polar GDGTs in aquatic environments

    Science.gov (United States)

    Peterse, F.; Moy, C. M.; Eglinton, T. I.

    2014-07-01

    We have performed incubation experiments in order to examine the fate of branched glycerol dialkyl glycerol tetraether (brGDGT) membrane lipids upon entering an aquatic environment and to asses the suitability of brGDGTs as tracers for fluvial land-sea transport of soil organic carbon. We incubated a soil from the Rakaia River catchment on the South Island of New Zealand using Rakaia River water and ocean water collected near the river mouth as inocula for a period of up to 152 days. The concentrations of brGDGTs derived from intact polar ("living"; IPL) lipids and core ("fossil"; CL) lipids remained stable over the course of the experiment, suggesting an absence of significant brGDGT production or degradation. Moreover, the lack of change in brGDGT distribution during the experiment implies that the initial soil signature remains unaltered during transport through the aquatic environment, at least over the time frame of the experiment. In contrast, the total pool of isoprenoid GDGTs (isoGDGTs), currently attributed to soil Thaumachaeota, increased substantially (27-72%) in all incubation setups by the end of the experiment. As a consequence, a decrease in Branched and Isoprenoid Tetraether (BIT) index values - a proxy for the relative input of fluvially discharged soil material into a marine system - became evident after an incubation period of 30 days, with a maximum final decrease of 0.88 to 0.74 in the experiment with river water. The relative distribution within the isoGDGT pool shows changes with time, suggesting different membrane adaptation rates to the aquatic environment, or a shift in source organism(s). While the stability of soil brGDGTs in aquatic environments reinforces their potential as tracers for land-sea transport of soil organic carbon and their use in paleoclimate reconstructions, the distributional differences between GDGTs in river water and nearby soil indicate that further research is needed to pinpoint the sources of GDGTs that are

  5. Investigation of individual radiation exposures from discharges to the aquatic environment: techniques used in habits surveys

    International Nuclear Information System (INIS)

    The techniques used by the Fisheries Radiobiological Laboratory (FRL) in conducting habits surveys are described and discussed. The main objectives of these surveys are to investigate exposure pathways to the public resulting from radioactive discharges to the aquatic environment and to provide the basic data from which critical groups can be identified. Preparation, conduct and interpretation of the results of surveys are described and possible errors obtained by the interview technique are highlighted. A means of verifying the results of interviews by a logging technique has been devised and some comparative results are presented. (author)

  6. Production of extracellular nucleic acids by genetically altered bacteria in aquatic-environment microcosms

    International Nuclear Information System (INIS)

    The factors which affect the production of extracellular DNA by genetically altered strains of Escherichia coli, Pseudomonas aeruginosa, Pseudomonas cepacia, and Bradyrhizobium japonicum in aquatic environments were investigated. Cellular nucleic acids were labeled in vivo by incubation with [3H]thymidine or [3H]adenine, and production of extracellular DNA in marine waters, artificial seawater, or minimal salts media was determined by detecting radiolabeled macromolecules in incubation filtrates. The presence or absence of the ambient microbial community had little effect on the production of extracellular DNA. Three of four organisms produced the greatest amounts of extracellular nucleic acids when incubated in low-salinity media (2% artificial seawater) rather than high-salinity media (10 to 50% artificial seawater). The greatest production of extracellular nucleic acids by P. cepacia occurred at pH 7 and 37 degree C, suggesting that extracellular-DNA production may be a normal physiologic function of the cell. Incubation of labeled P. cepacia cells in water from Bimini Harbor, Bahamas, resulted in labeling of macromolecules of the ambient microbial population. Collectively these results indicate that (i) extracellular-DNA production by genetically altered bacteria released into aquatic environments is more strongly influenced by physicochemical factors than biotic factors, (ii) extracellular-DNA production rates are usually greater for organisms released in freshwater than marine environments, and (iii) ambient microbial populations can readily utilize materials released by these organisms

  7. Distribution of quinolones, sulfonamides, tetracyclines in aquatic environment and antibiotic resistance in Indochina

    Directory of Open Access Journals (Sweden)

    Satoru eSuzuki

    2012-02-01

    Full Text Available Southeast Asia has become the center of rapid industrial development and economic growth. However, this growth has far outpaced investment in public infrastructure, leading to the unregulated release of many pollutants, including wastewater-related contaminants such as antibiotics. Antibiotics are of major concern because they can easily be released into the environment from numerous sources, and can subsequently induce development of antibiotic-resistant bacteria. Recent studies have shown that for some categories of drugs this source-to-environment antibiotic resistance relationship is more complex. This review summarizes current understanding regarding the presence of quinolones, sulfonamides, and tetracyclines in aquatic environments of Indochina and the prevalence of bacteria resistant to them. Several noteworthy findings are discussed: 1 quinolone contamination and the occurrence of quinolone resistance are not correlated; 2 occurrence of the sul sulfonamide resistance gene varies geographically; and 3 microbial diversity might be related to the rate of oxytetracycline resistance.

  8. Influence of Biological Macromolecules and Aquatic Chemistries on the Inhibition of Nitrifying Bacteria by Silver Nanoparticles

    Science.gov (United States)

    Radniecki, T. S.; Anderson, J. W.; Schneider, M. C.; Stankus, D. P.; Nason, J. A.; Semprini, L.

    2010-12-01

    The use of silver nanoparticles (Ag-NP) as a broad spectrum biocide in a wide range of consumer goods has grown exponentially since 2006 (1), which may result in an increased release of Ag-NP into wastewater streams and ultimately the receiving bodies of water. Ammonia oxidizing bacteria (AOB) play a critical role in the global nitrogen cycle through the oxidation of ammonia (NH3) to nitrite (NO2-) and are widely considered to be the most sensitive microbial fauna in the environment being readily inhibited by contaminants, including Ag-NP (2). This research used physiological techniques in combination with physical/chemical assays to characterize the inhibition of Nitrosomonas europaea, the model AOB, by silver ions (Ag+), 3-5 nm Ag-NP, 20 nm Ag-NP and 80 nm Ag-NP under a variety of aqueous chemistries. In addition, the stability of Ag-NP suspensions was examined under a variety of aqueous chemistries including in the presences of divalent cations, chloride anions, natural organic matter (NOM), proteins (BSA) and lipopolysaccharides (alginate). Using the stable Ag-NP/test media suspensions, N. europaea was found to be extremely sensitive to Ag+, 3-5 nm Ag-NP, 20 nm Ag-NP and 80 nm Ag-NP with concentrations of 0.1, 0.12, 0.5 and 1.5 ppm, respectively, resulting in a 50% decrease in nitrification rates. The inhibition was correlated with the amount of Ag+ released into solution. It is suspected that the inhibition observed from Ag-NP exposure is caused by the liberated Ag+. The aquatic chemistry of the test media was found to have a profound influence on the stability of Ag-NP suspensions. The presence of Ag ligands (e.g. EDTA and Cl-) reduced toxicity of Ag-NP through the formation of Ag-ligand complexes with the liberated Ag+. The presence of divalent cations (e.g. Ca2+ or Mg2+) resulted in the rapid aggregation of Ag-NP leading to a decrease in Ag+ liberation and thus a decrease in N. europaea inhibition. The presence of 5 ppm NOM resulted in a highly stable Ag

  9. A study of bioaccumulation occurring in a spatial and temporal aquatic environment

    International Nuclear Information System (INIS)

    The impacts of spatial, temporal, and hydrodynamics on the bioaccumulation in the Chernobyl cooling lake were evaluated using a two-dimensional aquatic exposure assessment model. The model framework integrated spatial and temporal heterogeneity effects of radioactive environments, changes in abundance and distribution of aquatic populations, spatial and temporal dependent (or density-dependent) radionuclide ingestion rates, and population biomass changes. Plankton population growth was integrated into the hydrodynamic-transport model to determine the plankton biomass density change and distributions. The exposure estimation was conducted in a two-dimensional finite element mesh which was used in the hydrodynamic-transport model. Results indicated that bioaccumulation factors with the assumption of steady-state and homogeneous conditions significantly over-estimated the radionuclide concentration accumulated in fish. The impacts of changes of biomass distributions and variable ingestion rates on the bioaccumulation varied spatially and temporally. Results also revealed that a higher radiobiological turn-over rate could be a dominate factor in determining the radionuclide fate in biota when the ecological processes, such as population growth, were relatively slow. Two different predator-prey relationships were applied. Their impacts on the bioaccumulation of fish varied spatially and temporally. Overall, the results suggest that a more realistic physical description of contaminated environments and ecosystems is necessary in studying bioaccumulation occurring in nature

  10. Medicinal Water? The occurrence and fate of pharmaceuticals in aquatic environments A short communication

    Directory of Open Access Journals (Sweden)

    Ricardo Sánchez-Murillo

    2016-03-01

    Full Text Available Although very little is known about the transport, fate and toxic effects of medical compounds in aquatic environments, the presence of these compounds in potable water sources can no longer be overlooked. We can argue that trace concentrations of drugs in the water is relatively a minor problem, however, the current and future demands on global potable freshwater supplies will probably lead to greater incidents of indirect and direct water-reuse situations at the local, regional, and cross-border levels. It is important to remark that the solution of this emerging ecological issue does not rely on new and better wastewater treatment technologies, but a new paradigm of responsibility and the understanding of the relations between anthropogenic actions and their ecological effects as well. The objective of this brief communication is to present the state of the art of research conducted in the last decade in Europe and United States concerning the presence of pharmaceuticals products in aquatic environments.

  11. Measurement and interpretation of microbial adenosine tri-phosphate (ATP) in aquatic environments.

    Science.gov (United States)

    Hammes, Frederik; Goldschmidt, Felix; Vital, Marius; Wang, Yingying; Egli, Thomas

    2010-07-01

    There is a widespread need for cultivation-free methods to quantify viability of natural microbial communities in aquatic environments. Adenosine tri-phosphate (ATP) is the energy currency of all living cells, and therefore a useful indicator of viability. A luminescence-based ATP kit/protocol was optimised in order to detect ATP concentrations as low as 0.0001 nM with a standard deviation of water samples from a variety of aquatic environments (drinking water, groundwater, bottled water, river water, lake water and wastewater effluent) were analysed for extracellular ATP and microbial ATP in comparison with flow-cytometric (FCM) parameters. Microbial ATP concentrations ranged between 3% and 97% of total ATP concentrations, and correlated well (R(2)=0.8) with the concentrations of intact microbial cells (after staining with propidium iodide). From this correlation, we calculated an average ATP-per-cell value of 1.75x10(-10)nmol/cell. An even better correlation (R(2)=0.88) was observed between intact biovolume (derived from FCM scatter data) and microbial ATP concentrations, and an average ATP-per-biovolume value of 2.95x10(-9)nmol/microm(3) was calculated. These results support the use of ATP analysis for both routine monitoring and research purposes, and contribute towards a better interpretation of ATP data. PMID:20605621

  12. Investigation and assessment of tritium concentration of aquatic environment surrounding haiyang nuclear power plant

    International Nuclear Information System (INIS)

    Objective: To investigate tritium concentrations of aquatic environment surrounding Haiyang nuclear power plant, and make a analysis of the influencial factors of the tritium concentration; to assess the accumulated-effective dose of the residents surrounding nuclear power plant. Methods: We collected 16 sample points, including surface water, groundwater, drinking water and sea water within 30 km surrounding Haiyang nuclear power plant in wet period and dry period. The pretreatment and preparation of samples referred to the recommended methods of the national standards GB 12375-90. The low background liquid scintillation spectrometer is used to measure the tritium concentration. Result: The average level of the tritium concentration of water samples was (0.62 ± 0.163) Bq · L-1, the range of the tritium concentrations was from 0.27Bq · L-1 to 0.93Bq · L-1. The difference of the tritium concentrations between two different periods analyzed by the paired t test was considered statistically significant. (P-1, 0.008 μ Sv · a-1, 0.007 μ Sv · a-1, respectively. Conclusion: The activity concentration of tritium in the aquatic environment surrounding Haiyang nuclear power plant was at the lower level than that of others; according to the limited value that is regulated by basic standards for protection against ionizing radiation and of the safety of radiation sources (GB 18871-2002) (2 mSv), the accumulated-effective dose which residents suffered was in background level of radiation. (authors)

  13. Isolation and characterization of Arcobacter spp. from fresh seafood and the aquatic environment.

    Science.gov (United States)

    Laishram, Martina; Rathlavath, Srinu; Lekshmi, Manjusha; Kumar, Sanath; Nayak, Binaya Bhusan

    2016-09-01

    Arcobacter is an emerging pathogen associated with foods of animal origin. Members of the genus Arcobacter are increasingly being isolated from fish, shellfish and the aquatic environment. In the present study, we analyzed fish, shellfish and water samples for the presence of Arcobacter spp. by conventional isolation as well as by direct PCR on the enrichment broth. Of 100 samples comprising of 42 finfish, 34 shellfish and 24 water samples analyzed, Arcobacter spp. was isolated from 8 (19%) finfish, 5 (14.7%) shellfish and 5 (20.8%) water samples. Arcobacter DNA was detected in 24 (24%) samples by direct PCR on the enrichment broth. Based on m-PCR specific to different Arcobacter spp. and 16S rRNA sequence analyses, majority (19) of the isolates were identified as Arcobacter butzleri, while two isolates were Arcobacter mytili. All Arcobacter butzleri isolates harbored putative virulence genes cadF, ciaB, mviN, pldA, tlyA and cj1349. The two isolates of A. mytili harbored mviN and cj1349 genes only. The study highlights emerging problem of the contamination of aquatic environment and fresh seafood with potentially pathogenic Arcobacter spp. PMID:27261768

  14. Indirect photochemical transformations of acyclovir and penciclovir in aquatic environments increase ecological risk.

    Science.gov (United States)

    An, Jibin; Li, Guiying; An, Taicheng; Nie, Xiangping

    2016-03-01

    Acyclovir and penciclovir, 2 antiviral drugs, are increasingly detected in aquatic environments. The present study explores the natural photochemical transformation mechanisms and fate of these drugs, examining direct and indirect photochemical transformation under simulated sunlight irradiation. The 2 antiviral drugs are photostable under certain conditions but significantly degrade in the presence of chromophoric dissolved organic matter (DOM). The degradation rate associated with the drugs' indirect photochemical transformation scaled with chromophoric DOM concentration. Quenchers and sensitizers were used to identify indirect photochemical transformation mechanism. Results suggested that both pharmaceuticals could be transformed by reacting with (1) O2 , (•) OH, and excited chromophoric DOM. The (1) O2 played an important role in indirect photochemical transformation. Furthermore, the reaction kinetics between their substructural molecules, guanine, isocytosine, and imidazole, with different reactive oxygen species were evaluated to determine which substrate functionalities were most susceptible to singlet oxygenation. Imidazole was identified as the reaction site for (1) O2 , and preliminary (1) O2 oxidation mechanisms were further evaluated based on liquid chromatographic-tandem mass spectrometric results. Finally, aquatic ecotoxicity assessment of phototransformed solutions revealed that the degradation of acyclovir and penciclovir may not ultimately diminish environmental risk because of either formation of more toxic intermediates than parent pharmaceuticals or some synergistic effects existing between the intermediates. Environ Toxicol Chem 2016;35:584-592. © 2015 SETAC. PMID:26356329

  15. Applying physicochemical approaches to control phosphogypsum heavy metal releases in aquatic environment.

    Science.gov (United States)

    Ammar, Rawaa; El Samrani, Antoine G; Kazpard, Véronique; Bassil, Joseph; Lartiges, Bruno; Saad, Zeinab; Chou, Lei

    2013-12-01

    One of the most important sources of solid waste in the Mediterranean Basin ecosystem originated from the phosphate fertilizer industries, which discharge phosphogypsum (PG) directly into aquatic environments or are stacked on stockpiles. The present study investigates metal release from PG under the influence of variable pH, increasing PG mass content, and complexing organic matter ligands. Major ions from PG leachates, grain size and charge, main functional groups along with metal leachability (Pb, Cd, Cr, Cu, and Zn) were determined using ion chromatography, laser diffraction, zetameter, Fourier transform infrared spectroscopy, and atomic absorption spectroscopy, respectively. The complete dissolution of PG recorded is at 2 g/L. Saturation and supersaturation with respect to PG may occur at concentrations of 3 and 4 g/L, respectively, revealing a clustering phenomenon leading to heavy metal encapsulation within the aggregates. Organic ligands such as citrate may trigger the cationic exchange within the PG suspension leading to ion release. As these factors are considered as specific process involving the release of contaminants from PG during storage under natural conditions, this study could set the foundations for PG remediation in aquatic environment. Organic ligands under controlled pH conditions could be utilized in treating fertilizer industrial wastes by taking into consideration the particularity of the receiving area, thus decreasing metal hazardous impact on natural media. PMID:23764982

  16. Daphnia as a model organism in limnology and aquatic biology: introductory remarks

    Directory of Open Access Journals (Sweden)

    Adam PETRUSEK

    2011-08-01

    Full Text Available Cladocerans of the genus Daphnia are keystone pelagic filter feeders in many temperate ponds and lakes. They have also become popular model organisms in various biological disciplines, from aquatic ecology to biomedical sciences. The crucial features that make these organisms excellent experimental models are their cyclical parthenogenetic life cycle together with easy culturing and handling. Thanks to these characteristics, the number of publications dealing with Daphnia is rapidly growing. The special insert to the Journal of Limnology on Daphnia biology contains contributions that deal directly or indirectly with the reproduction and development of these water fleas, in relation to various ecological factors. These include predator-prey interactions and their impact on morphology, population dynamics, or senescence-related traits, growth of daphnids on a diet consisting of invasively spreading cyanobacteria, and also the impact of extreme floods on a Daphnia population (and particularly on its dormant ephippial egg bank in a reservoir. Here, we discuss these presented works, and point out the potential lines of research that may improve the generalisation of their findings.

  17. A novel photosynthetic strategy for adaptation to low-iron aquatic environments

    Science.gov (United States)

    Chauhan, D.; Folea, I.M.; Jolley, C.C.; Kouril, R.; Lubner, C.E.; Lin, S.; Kolber, D.; Wolfe-Simon, Felisa; Golbeck, J.H.; Boekema, E.J.; Fromme, P.

    2011-01-01

    Iron (Fe) availability is a major limiting factor for primary production in aquatic environments. Cyanobacteria respond to Fe deficiency by derepressing the isiAB operon, which encodes the antenna protein IsiA and flavodoxin. At nanomolar Fe concentrations, a PSI-IsiA supercomplex forms, comprising a PSI trimer encircled by two complete IsiA rings. This PSI-IsiA supercomplex is the largest photosynthetic membrane protein complex yet isolated. This study presents a detailed characterization of this complex using transmission electron microscopy and ultrafast fluorescence spectroscopy. Excitation trapping and electron transfer are highly efficient, allowing cyanobacteria to avoid oxidative stress. This mechanism may be a major factor used by cyanobacteria to successfully adapt to modern low-Fe environments. ?? 2010 American Chemical Society.

  18. Pollution Pathways of Pharmaceutical Residues in the Aquatic Environment on the Island of Mallorca, Spain

    DEFF Research Database (Denmark)

    Rodríguez-Navas, Carlos; Björklund, Erland; Bak, Søren Alex;

    2013-01-01

    of discharge of the pharmaceuticals into the aquatic environment. The data indicate that reuse of treated domestic wastewater for irrigation (which supplies some 30 % of the total water demand in Mallorca) contributes to the contamination of GW. In addition, leaching from landfills is identified as another......This work determines the principal environmental pollution pathways of pharmaceuticals on the island of Mallorca (Spain). The evaluation was made on the basis of the quantification of pharmaceutical residues by liquid chromatography–tandem mass spectrometry in several environmental water samples......, including wastewater-treatment plant effluents, municipal solid waste landfill leachates, groundwater (GW), and marine water. An overall set of 19 pharmaceuticals has been identified in the environment of the 27 human pharmaceuticals investigated in this study. WWTP effluents are the main source...

  19. Effect-Based Tools for Monitoring and Predicting the Ecotoxicological Effects of Chemicals in the Aquatic Environment

    Directory of Open Access Journals (Sweden)

    Richard E. Connon

    2012-09-01

    Full Text Available Ecotoxicology faces the challenge of assessing and predicting the effects of an increasing number of chemical stressors on aquatic species and ecosystems. Herein we review currently applied tools in ecological risk assessment, combining information on exposure with expected biological effects or environmental water quality standards; currently applied effect-based tools are presented based on whether exposure occurs in a controlled laboratory environment or in the field. With increasing ecological relevance the reproducibility, specificity and thus suitability for standardisation of methods tends to diminish. We discuss the use of biomarkers in ecotoxicology including ecotoxicogenomics-based endpoints, which are becoming increasingly important for the detection of sublethal effects. Carefully selected sets of biomarkers allow an assessment of exposure to and effects of toxic chemicals, as well as the health status of organisms and, when combined with chemical analysis, identification of toxicant(s. The promising concept of “adverse outcome pathways (AOP” links mechanistic responses on the cellular level with whole organism, population, community and potentially ecosystem effects and services. For most toxic mechanisms, however, practical application of AOPs will require more information and the identification of key links between responses, as well as key indicators, at different levels of biological organization, ecosystem functioning and ecosystem services.

  20. Semipermeable membrane devices in monitoring of organic pollutants in the aquatic environment

    Energy Technology Data Exchange (ETDEWEB)

    Sabaliunas, D.

    1999-03-01

    Semipermeable membrane devices (SPMDs) are passive samplers capable of concentrating hydrophobic chemicals from water, sediments, soil and air. They consist of layflat polymeric membrane such as polyethylene containing a thin film of synthetic lipid such as triolein. The transport of hydrophobic chemicals through the membrane into the lipid is governed by the process of passive diffusion. Therefore, SPMDs sample chemicals in a way similar to organisms. This thesis deals with the application of SPMDs in the monitoring of concentrations and effects of organic pollutants in the aquatic environment. SPMDs were exposed to various pesticides (organochlorines, synthetic pyrethroids, dinitroanilines, amides) in laboratory flow-through experiments to study the uptake kinetics of organic chemicals from water. To compare the uptake of model compounds by SPMDs and aquatic organisms, the membrane samplers were exposed to chemicals side-by-side with bivalves. Mixtures of chemicals accumulated by SPMDs and mussels were tested in standard toxicity and genotoxicity assays (Microtox, Mutatox, invertebrate toxicity tests, the Ames test, sister chromatid exchange test). These studies showed that the uptake pattern of organic compounds by SPMDs and aquatic organisms was similar, and the passive samplers accumulated levels of chemicals sufficient for standard bioassays. To further validate the method, SPMDs were deployed in a number of polluted water sources in Lithuania. Bioassay-directed fractionation and chemical analytical methods were used to identify pollutants sampled (PAHs, PCBs, organochlorines) and their effects were evaluated in bioassays. SPMDs proved to be useful tools in monitoring of organic pollutants under the field conditions. Criteria for bioassays to be integrated with the SPMD technique were defined based on the results of these studies. Some important factors in the integration of SPMDs and bioassays (toxicity of SPMD-inherent oleic and sediment

  1. Guidelines to Avoid Biocontamination of Antarctic Subglacial Aquatic Environments: Forward Contamination Concerns, Environmental Management and Scientific Stewardship of Icy analogue environments

    Science.gov (United States)

    Race, M. S.; Hobbie, J.; et al.

    2007-12-01

    For more than a decade, scientists and space mission planners have recognized the importance of collaborative information exchange with the Antarctic research community to address their many shared exploration challenges, from drilling methods, remote sample collection, and data interpretation, to concerns about cross contamination that could adversely impact both the environment and interpretation of scientific data. Another shared concern exists in the regulatory realm; both the Antarctic and outer space environments are subject to separate international treaties that impose regulatory controls and oversight with serious implications for exploration planning. In recent years, both communities have faced the need to adjust their regulatory controls in light of fast-paced advances in scientific understanding of extreme environments, particularly related to potential microbial life. Both communities have sought and received advice from the National Research Council (NRC) through studies that suggested ways to update their respective oversight and regulatory systems while allowing for continued scientific exploration. A recently completed NRC study "Exploration of Antarctic Subglacial Aquatic Environments: Environmental and Scientific Stewardship" provided a suite of recommendations to address1) 'cleanliness' levels necessary for equipment and devices used in exploration of subglacial aquatic environments, as well as 2) the scientific basis for contamination standards, and 3) the steps for defining an overall exploration strategy conducive to sound environmental management and scientific stewardship. This talk will present the findings of the recent multinational NRC study, which is likely to translate into useful information for analogue studies that proceed to test techniques and capabilities for exploring an Europan ocean, other icy celestial locations, and related science targets on Earth. As the science and exploration of subglacial environments grows beyond its

  2. The main sources of pollution of the aquatic environment in Hellas

    Science.gov (United States)

    Koumantakis, J.; Dimitrakopoulos, D.; Markantonis, K.; Grigorakou, E.; Vassiliou, E.

    2003-04-01

    The research team of the laboratory of Engineering Geology &Hydrogeology of NTUA and P.P.C. have carried out several research projects since 1990. The conclusions of these projects for the main sources of pollution of the aquatic environment in Hellas are the following: Human activities : a) Urban and industrial wastes (solid and liquids) are disposed or discharged to the surface or groundwater bodies causing degradation of their quality (case studies of Athens Basin, Lavrio region, Atalanti plain), b) intensive use of pesticides and fertilizers for agriculture, through the process of percolation or leaching causes the deterioration of aquifers and surface water (case studies of Plolemais Basin, Korinth region, Elassona Basin, Atalanti plain, Thrapsana Basin Iraklio), c) current exploitations and old or abandoned mining sites, disturb the aquatic environment and create new hydraulic connections between clean and polluted aquifers or the sea (case studies of Lavrio region, Ptolemais Basin, Megalopoli Basin), d) over-pumping of aquifers mainly for irrigation but also in some cases for dewatering of mines, results in continues drawdown of the groundwater level and intrusion of sea (case studies of Korinth region, Athens basin, Naxos island, Nea Peramos Kavala, Marathon, Argolida Field, Atalanti plain, Achaia region, Stratoni area Chalkidiki, Gouves Iraklio). Geological Environment: a) extensive karstification of limestones that spread up all over the Greek region (33%) causes the intrusion of the sea far into the land (case studies of Lavrio region, Kefalonia island, Hymettus mountain), b) the chemical composition of the geological formations through the process of ion exchange and solubility pollute the groundwater resources (case studies of Vegoritis Basin, Katsika Chalkidiki, Florina region). The proposed measures to face these problems are : - the orthological management of the water resources - the artificial recharge of the aquifers, - proper waste management

  3. Transport and fate of radionuclides in aquatic environments - the use of ecosystem modelling for exposure assessments of nuclear facilities

    International Nuclear Information System (INIS)

    In safety assessments of nuclear facilities, a wide range of radioactive isotopes and their potential hazard to a large assortment of organisms and ecosystem types over long time scales need to be considered. Models used for these purposes have typically employed approaches based on generic reference organisms, stylised environments and transfer functions for biological uptake exclusively based on bioconcentration factors (BCFs). These models are of non-mechanistic nature and involve no understanding of uptake and transport processes in the environment, which is a severe limitation when assessing real ecosystems. In this paper, ecosystem models are suggested as a method to include site-specific data and to facilitate the modelling of dynamic systems. An aquatic ecosystem model for the environmental transport of radionuclides is presented and discussed. With this model, driven and constrained by site-specific carbon dynamics and three radionuclide specific mechanisms: (i) radionuclide uptake by plants (ii) excretion by animals, and (iii) adsorption to organic surfaces, it was possible to estimate the radionuclide concentrations in all components of the modelled ecosystem with only two radionuclide specific input parameters (BCF for plants and K d). The importance of radionuclide specific mechanisms for the exposure to organisms was examined, and probabilistic and sensitivity analyses to assess the uncertainties related to ecosystem input parameters were performed. Verification of the model suggests that this model produces analogous results to empirically derived data for more than 20 different radionuclides

  4. Extracellular enzyme activities of aquatic bacteria in polluted environment: 2. Amylolytic activity

    International Nuclear Information System (INIS)

    Water samples were taken from Lake Drukshiai tributaries (Ricanka); Gulbinele Stream affected by urban rain sewerage from Visaginas; Gulbinele Stream into which municipal sewage from Visaginas (MS) and industrial rain sewerage from the Ignalina NPP and their mouth, and Lake Dringis. Lake Dringis, in Aukstaitija National Park, was selected as an ecosystem pattern of a weak anthropogenic influence, while Lake Drukshiai was chosen as a regularly polluted water body. Lake Drukshiai, the cooling basin of the Ignalina NPP (IRS-1.2), is being polluted with industrial and municipal sewage through its tributaries. The amylolytic activity (AA) of heterotrophic aquatic bacteria was tested. The highest total mean AA of aquatic bacteria was calculated in Lake Dringis. Here, the results were significantly higher than in Lake Drukshiai tributaries and their mouths, excepting the mouths of the Ricanka and MS. The lowest mean of AA in Lake Drukshiai was characteristic of the IRS-1.2 tributary. A comparison of the mean AA of active isolates showed that certain bacterial strains from the sites of varying degrees of pollution could be noted for a relatively high level of enzymatic activity. Thus, anthropogenic pollution exerts a negative effect on the total mean AA, although certain strains of bacteria are able to adapt to the stressful environment and remain active. (author)

  5. Antibiotic resistance profiles of Pseudomonas aeruginosa isolated from various Greek aquatic environments.

    Science.gov (United States)

    Olga, Pappa; Apostolos, Vantarakis; Alexis, Galanis; George, Vantarakis; Athena, Mavridou

    2016-05-01

    A large number of antibiotic-resistantP. aeruginosaisolates are continuously discharged into natural water basins mainly through sewage. However, the environmental reservoirs of antibiotic resistance factors are poorly understood. In this study, the antibiotic resistance patterns of 245 isolates from various aquatic sites in Greece were analysed. Twenty-three isolates with resistance patterns cefotaxime-aztreonam-ceftazidime, cefotaxime-aztreonam-meropenem, cefotaxime-ceftazidime-meropenem, cefotaxime-ceftazidime-aztreonam-meropenem and cefotaxime-ceftazidime-cefepime-aztreonam-meropenem were screened phenotypically for the presence of extended spectrum β-lactamases (ESBLs), while 77 isolates with various resistant phenotypes were screened for the presence of class 1 and class 2 integrase genes. The aztreonam-resistant isolates and ESBL producers were the main resistant phenotypes in all habitats tested. In 13/77 isolates class 1 integron was detected, while all tested isolates were negative for the presence of the class 2 integrase gene. CTX-M group 9 β-lactamase was present in a small number of isolates (three isolates) highlighting the emergence of ESBL genes in aquatic environments. As a conclusion, it seems that Greek water bodies could serve as a potential reservoir of resistantP. aeruginosaisolates posing threats to human and animal health. PMID:26917780

  6. The evolutionary puzzle of egg size, oxygenation and parental care in aquatic environments.

    Science.gov (United States)

    Braga Goncalves, Ines; Ahnesjö, Ingrid; Kvarnemo, Charlotta

    2015-08-22

    Offspring fitness generally improves with increasing egg size. Yet, eggs of most aquatic organisms are small. A common but largely untested assumption is that larger embryos require more oxygen than they can acquire through diffusion via the egg surface, constraining egg size evolution. However, we found no detrimental effects of large egg size on embryo growth and survival under hypoxic conditions. We tested this in the broad-nosed pipefish, Syngnathus typhle, whose males provide extensive care (nourishment, osmoregulation and oxygenation) to their young in a brood pouch on their bodies. We took advantage of this species' pronounced variation in egg size, correlating positively with female size, and tested the effect of hypoxia (40% dissolved oxygen) versus fully oxygenated (100%) water on embryo size and survival of large versus small eggs after 18 days of paternal brooding. Egg size did not affect embryo survival, regardless of O2 treatment. While hypoxia affected embryo size negatively, both large and small eggs showed similar reductions in growth. Males in hypoxia ventilated more and males with large eggs swam more, but neither treatment affected their position in the water column. Overall, our results call into question the most common explanation for constrained egg size evolution in aquatic environments. PMID:26290070

  7. Evaluation and modeling of the parameters affecting fluoride toxicity level in aquatic environments by bioassay method

    Directory of Open Access Journals (Sweden)

    Hamid Reza Shamsollahi

    2014-04-01

    Full Text Available Background: Fluoride exists in various forms in nature and water resources. , The rising level of fluoride in water resources due to discharge of industrial effluents can cause toxicity in aquatic organisms. To prevent toxicity, it is necessary to determine maximum fluoride toxicity as well as effluent discharge limits. The aim of this study was to determine the maximum fluoride toxicity and the factors affecting fluoride toxicity to provide a model in order to determine the effluent discharge limits. Methods: Daphnia magna bioassay in the absence of confounding factors was used to determine the maximum level of fluoride toxicity. Then, bioassay was repeated in the presence of the confounding factors (hardness, temperature and exposure time to determine their effects. Results: In the absence of intervening factors, fluoride LC50 levels determined after 24, 48 and 72 hours exposure were 4.9, 46.5 and 38.7 mg/l, respectively.. Also, the influence of confounding factors on LC50 values was reported significant by Minitab software. Conclusion: Increasing the water hardness reduced fluoride toxicity, and increasing the water temperature and exposure time increased fluoride toxicity in aquatic environments. Therefore, while determining the wastewater discharge limit in terms of fluoride concentration, it is essential to take the effect of confounding factors on fluoride toxicity into account in order to prevent toxicity in the open water resources.

  8. Aquatic productivity: isotopic tracer aided studies of chemical-biological interactions

    International Nuclear Information System (INIS)

    Inland waters subject to the accumulation and effects of trace contaminants are discussed and a review of international research projects on this subject is given. The following aspects are specially discussed: aquatic nitrogen and agriculture; aquatic ecosystems in arid zones of developing countries; micronutrients in aquatic ecosystems; microbiological activity (''primary production''); enzymic methods in water quality determinations. Recommendations of the Joint FAO/IAEA Advisory Group for measures to be taken in order to protect water quality are also given

  9. Theoretical analysis of the cost of antagonistic activity for aquatic bacteria in oligotrophic environments.

    Science.gov (United States)

    Aguirre-von-Wobeser, Eneas; Eguiarte, Luis E; Souza, Valeria; Soberón-Chávez, Gloria

    2015-01-01

    Many strains of bacteria produce antagonistic substances that restrain the growth of others, and potentially give them a competitive advantage. These substances are commonly released to the surrounding environment, involving metabolic costs in terms of energy and nutrients. The rate at which these molecules need to be produced to maintain a certain amount of them close to the producing cell before they are diluted into the environment has not been explored so far. To understand the potential cost of production of antagonistic substances in water environments, we used two different theoretical approaches. Using a probabilistic model, we determined the rate at which a cell needs to produce individual molecules in order to keep on average a single molecule in its vicinity at all times. For this minimum protection, a cell would need to invest 3.92 × 10(-22) kg s(-1) of organic matter, which is 9 orders of magnitude lower than the estimated expense for growth. Next, we used a continuous model, based on Fick's laws, to explore the production rate needed to sustain minimum inhibitory concentrations around a cell, which would provide much more protection from competitors. In this scenario, cells would need to invest 1.20 × 10(-11) kg s(-1), which is 2 orders of magnitude higher than the estimated expense for growth, and thus not sustainable. We hypothesize that the production of antimicrobial compounds by bacteria in aquatic environments lies between these two extremes. PMID:26074891

  10. Investigation of the transport of actinide-bearing soil colloids in the soil-aquatic environment

    International Nuclear Information System (INIS)

    Uranium-233 particle size dependent distribution ratios for the 10 to 60 range were determined for muscatine silt loam, Burbank loamy sand, Ritzville silt loam, Fuquay sand, and Idaho sandy clay. A mathematical method for the analysis of centrifuge data was developed to determine particle size dependent distribution ratio for the 10 to 60 nm range. Comparison of the distribution ratio data for the 0 to 60 nm particle size range strongly suggests that particles in the 1 to 10 nm (8000 to 50,000 MW) range play a dominate role. Since these particles are probably humic acid polymers, future research should be focused on humic acid complexing of radionuclides. A mathematical analysis is given to demonstrate the role of humic acid complexing in the transport of radionuclides in the soil-aquatic environment

  11. Prediction of climate impacts on pesticide leaching to the aquatic environments

    Energy Technology Data Exchange (ETDEWEB)

    Henriksen, Hans Joergen; Rosenbom, A.; van der Keur, P.; Kjaer, J.; Sonnenborg, T. [GEUS Danmark, Copenhagen (Denmark); Olesen, J.E. [Aarhus Univ., Tjele (Denmark); Nistrup Joergensen, L. [Aarhus Unv., Slagelse (Denmark); Boessing Christensen, O. [Danmarks Meteorologiske Institut (DMI), Copenhagen (Denmark)

    2013-10-01

    The report evaluates direct (precipitation, actual evapotranspiration and temperature) and indirect (crop rotations, crop management, and pesticide use) climatic change effects on pesticide-leaching to groundwater and the aquatic environment by use of MACRO and MIKE SHE model. The analysis is based on five model pesticides: low-dose herbicides, ordinary herbicides, strongly sorbing herbicides, fungicides and insecticides, and selected farm types (arable and dairy) for the variable saturated sandy soil (Jyndevad) and loamy soil (Faardrup). The evaluation has the aim at describing the implications of future climatic factors on pesticide leaching to groundwater as realistic as possible, based on realistic doses and parameters from MACRO setups from the Danish Pesticide Leaching Assessment Programme. (Author)

  12. Diatoms: a novel source for the neurotoxin BMAA in aquatic environments.

    Science.gov (United States)

    Jiang, Liying; Eriksson, Johan; Lage, Sandra; Jonasson, Sara; Shams, Shiva; Mehine, Martin; Ilag, Leopold L; Rasmussen, Ulla

    2014-01-01

    Amyotrophic lateral sclerosis (ALS) or Lou Gehrig's disease is a neurological disorder linked to environmental exposure to a non-protein amino acid, β-N-methylamino-L-alanine (BMAA). The only organisms reported to be BMAA-producing, are cyanobacteria--prokaryotic organisms. In this study, we demonstrate that diatoms--eukaryotic organisms--also produce BMAA. Ultra-high-performance liquid chromatography coupled with tandem mass spectrometry revealed the occurrence of BMAA in six investigated axenic diatom cultures. BMAA was also detected in planktonic field samples collected on the Swedish west coast that display an overrepresentation of diatoms relative to cyanobacteria. Given the ubiquity of diatoms in aquatic environments and their central role as primary producers and the main food items of zooplankton, the use of filter and suspension feeders as livestock fodder dramatically increases the risk of human exposure to BMAA-contaminated food. PMID:24392143

  13. A Study on the Evaluation Techniques of Pollutant Transport in Aquatic Environment

    International Nuclear Information System (INIS)

    A study on the numerical modeling has been performed to evaluate the characteristics of hydrodynamics and pollutant transport in aquatic environment such as river, lake, estuary and coastal areas. A EFDC among the lots of codes was selected to analyze the characteristics of code and the applications. A EFDC is a general-purpose modeling package for simulating three-dimensional flow, transport, and biogeochemical processes in surface water systems including rivers, lakes, estuaries, reservoirs, wetlands and coastal regions. The structure of the EFDC model includes four major modules: a hydrodynamic model, a water quality model, a sediment transport model, and a toxic model. This report was described the characteristics of the EFDC model and examples of application in lake, river, estuary and ocean

  14. Naphthenic acids degradation and toxicity mitigation in tailings wastewater systems and aquatic environments: a review.

    Science.gov (United States)

    Kannel, Prakash R; Gan, Thian Y

    2012-01-01

    Naphthenic acids, NAs (classical formula C(n)H(2n+z)O(2), where n is the carbon numbers, z represents zero or negative even integers), found in oil sands process waters (OSPWs), are toxic to aquatic environments depending upon several factors such as pH, salinity, molecular size and chemical structure of NAs. Among various available methods, biodegradation seems to be generally the most cost-effective method for decreasing concentrations of NAs (n ≤ 21) and reducing their associated toxicity in OSPW, however the mechanism by which the biodegradation of NAs occurs are poorly understood. Ozonation is superior over biodegradation in decreasing higher molecular weight alkyl branched NAs (preferentially, n ≥ 22, -6 ≥ z ≥ -12) as well as enabling accelerated biodegradation and reducing toxicity. Photolysis (UV at 254 nm) is effective in cleaving higher molecular weight NAs into smaller fragments that will be easier for microorganisms to degrade, whereas photocatalysis can metabolize selective NAs (0 ≥ z ≥ -6) efficiently and minimize their associated toxicity. Phytoremediation is applicable for metabolizing specific NAs (O(2), O(3), O(4), and O(5) species) and minimizing their associated toxicities. Petroleum coke (PC) adsorption is effective in reducing the more structurally complex NAs (preferentially 12 ≥ n ≥ 18 and z = -10, -12) and their toxicity in OSPWs, depending upon the PC content, pH and temperature. Several factors have influence on the degradation of NAs in OSPWs and aquatic environments, which include molecular mass and chemical structure of NAs, sediment structure, temperature, pH, dissolved oxygen, nutrients, and bacteria types. PMID:22217078

  15. Transmission of Vibrio cholerae is antagonized by lytic phage and entry into the aquatic environment.

    Directory of Open Access Journals (Sweden)

    Eric J Nelson

    2008-10-01

    Full Text Available Cholera outbreaks are proposed to propagate in explosive cycles powered by hyperinfectious Vibrio cholerae and quenched by lytic vibriophage. However, studies to elucidate how these factors affect transmission are lacking because the field experiments are almost intractable. One reason for this is that V. cholerae loses the ability to culture upon transfer to pond water. This phenotype is called the active but non-culturable state (ABNC; an alternative term is viable but non-culturable because these cells maintain the capacity for metabolic activity. ABNC bacteria may serve as the environmental reservoir for outbreaks but rigorous animal studies to test this hypothesis have not been conducted. In this project, we wanted to determine the relevance of ABNC cells to transmission as well as the impact lytic phage have on V. cholerae as the bacteria enter the ABNC state. Rice-water stool that naturally harbored lytic phage or in vitro derived V. cholerae were incubated in a pond microcosm, and the culturability, infectious dose, and transcriptome were assayed over 24 h. The data show that the major contributors to infection are culturable V. cholerae and not ABNC cells. Phage did not affect colonization immediately after shedding from the patients because the phage titer was too low. However, V. cholerae failed to colonize the small intestine after 24 h of incubation in pond water-the point when the phage and ABNC cell titers were highest. The transcriptional analysis traced the transformation into the non-infectious ABNC state and supports models for the adaptation to nutrient poor aquatic environments. Phage had an undetectable impact on this adaptation. Taken together, the rise of ABNC cells and lytic phage blocked transmission. Thus, there is a fitness advantage if V. cholerae can make a rapid transfer to the next host before these negative selective pressures compound in the aquatic environment.

  16. Carbon Nanotube Integrative Sampler (CNIS) for passive sampling of nanosilver in the aquatic environment.

    Science.gov (United States)

    Shen, Li; Fischer, Jillian; Martin, Jonathan; Hoque, Md Ehsanul; Telgmann, Lena; Hintelmann, Holger; Metcalfe, Chris D; Yargeau, Viviane

    2016-11-01

    Nanomaterials such as nanosilver (AgNP) can be released into the aquatic environment through production, usage, and disposal. Sensitive and cost-effective methods are needed to monitor AgNPs in the environment. This work is hampered by a lack of sensitive methods to detect nanomaterials in environmental matrixes. The present study focused on the development, calibration and application of a passive sampling technique for detecting AgNPs in aquatic matrixes. A Carbon Nanotube Integrative Sampler (CNIS) was developed using multi-walled carbon nanotubes (CNTs) as the sorbent for accumulating AgNPs and other Ag species from water. Sampling rates were determined in the laboratory for different sampler configurations and in different aquatic matrixes. The sampler was field tested at the Experimental Lakes Area, Canada, in lake water dosed with AgNPs. For a configuration of the CNIS consisting of CNTs bound to carbon fiber (i.e. CNT veil) placed in Chemcatcher® housing, the time weighted average (TWA) concentrations of silver estimated from deployments of the sampler in lake mesocosms dosed with AgNPs were similar to the measured concentrations of "colloidal silver" (i.e. <0.22μm in size) in the water column. For a configuration of CNIS consisting of CNTs in loose powder form placed in a custom made housing that were deployed in a whole lake dosed with AgNPs, the estimated TWA concentrations of "CNIS-labile Ag" were similar to the concentrations of total silver measured in the epilimnion of the lake. However, sampling rates for the CNIS in various matrixes are relatively low (i.e. 1-20mL/day), so deployment periods of several weeks are required to detect AgNPs at environmentally relevant concentrations, which can allow biofilms to develop on the sampler and could affect the sampling rates. With further development, this novel sampler may provide a simple and sensitive method for screening for the presence of AgNPs in surface waters. PMID:27343941

  17. A multiple testing approach for hazard evaluation of complex mixtures in the aquatic environment: the use of diesel oil as a model.

    Science.gov (United States)

    Johnson, B T; Romanenko, V I

    1989-01-01

    Traditional single species toxicity tests and multiple component laboratory-scaled microcosm assays were combined to assess the toxicological hazard of diesel oil, a model complex mixture, to a model aquatic environment. The immediate impact of diesel oil dosed on a freshwater community was studied in a model pond microcosm over 14 days: a 7-day dosage and a 7-day recovery period. A multicomponent laboratory microcosm was designed to monitor the biological effects of diesel oil (1.0 mg litre(-1)) on four components: water, sediment (soil + microbiota), plants (aquatic macrophytes and algae), and animals (zooplanktonic and zoobenthic invertebrates). To determine the sensitivity of each part of the community to diesel oil contamination and how this model community recovered when the oil dissipated, limnological, toxicological, and microbiological variables were considered. Our model revealed these significant occurrences during the spill period: first, a community production and respiration perturbation, characterized in the water column by a decrease in dissolved oxygen and redox potential and a concomitant increase in alkalinity and conductivity; second, marked changes in microbiota of sediments that included bacterial heterotrophic dominance and a high heterotrophic index (0.6), increased bacterial productivity, and the marked increases in numbers of saprophytic bacteria (10 x) and bacterial oil degraders (1000 x); and third, column water acutely toxic (100% mortality) to two model taxa: Selenastrum capricornutum and Daphnia magna. Following the simulated clean-up procedure to remove the oil slick, the recovery period of this freshwater microcosm was characterized by a return to control values. This experimental design emphasized monitoring toxicological responses in aquatic microcosm; hence, we proposed the term 'toxicosm' to describe this approach to aquatic toxicological hazard evaluation. The toxicosm as a valuable toxicological tool for screening aquatic

  18. Monitoring of the aquatic environment by species accumulator of pollutants: a review

    Directory of Open Access Journals (Sweden)

    Oscar RAVERA

    2001-09-01

    Full Text Available This paper is a short review on the biomonitoring of aquatic environments by animal and plant species accumulators of toxic pollutants ("scavengers". This monitoring is based on the relationship between the pollutant concentration in the organism and that in its environment, and not on alterations produced by pollution on the biota. The latter is the basis of other types of biomonitoring, such as those based on the biotic and diversity indices and saprobic scale. The various aspects of monitoring by pollutant accumulators are illustrated; for example, the uptake and loss of pollutants, the "critical organs" and "tissues", the detoxification mechanisms and the most common factors (C.F., BAF, BSAF for establishing a connection between the pollutant concentration in the organism and that in its environment. Several examples of this monitoring on heavy metals, radioisotopes and organic micropollutants are reported. The advantages of this monitoring, the characteristics of the species to be used as bioaccumulators and some practical suggestions are listed. A close collaboration between the scientific teams working on the biomonitoring based on accumulator organisms and on the chemical monitoring is recommended from the scientific and economic point of view.

  19. Biological Diversity, Ecological Health and Condition of Aquatic Assemblages at National Wildlife Refuges in Southern Indiana, USA

    OpenAIRE

    Thomas Simon; Charles Morris; Joseph Robb; William McCoy

    2015-01-01

    Abstract The National Wildlife Refuge system is a vital resource for the protection and conservation of biodiversity and biological integrity in the United States. Surveys were conducted to determine the spatial and temporal patterns of fish, macroinvertebrate, and crayfish populations in two watersheds that encompass three refuges in southern Indiana. The Patoka River National Wildlife Refuge had the highest number of aquatic species with 355 macroinvertebrate taxa, six crayfish species, and...

  20. Animal protein production modules in biological life support systems: Novel combined aquaculture techniques based on the closed equilibrated biological aquatic system (C.E.B.A.S.)

    Science.gov (United States)

    Blüm, V.; Andriske, M.; Kreuzberg, K.; Schreibman, M. P.

    Based on the experiences made with the Closed Equilibrated Biological Aquatic System (C.E.B.A.S.) which was primarily deveoloped for long-term and multi-generation experiments with aquatic animals and plants in a space station highly effective fresh water recycling modules were elaborated utilizing a combination of ammonia oxidizing bacteria filters and higher plants. These exhibit a high effectivity to eliminate phosphate and anorganic nitrogen compounds and arc. in addidition. able to contribute to the oxygen supply of the aquatic animals. The C.E.B.A.S. filter system is able to keep a closed artificial aquatic ecosystem containing teleost fishes and water snails biologically stable for several month and to eliminate waste products deriving from degraded dead fishes without a decrease of the oxygen concentration down to less than 3.5 mg/l at 25 °C. More advanced C.E.B.A.S. filter systems, the BIOCURE filters, were also developed for utilization in semiintensive and intensive aquaculture systems for fishes. In fact such combined animal-plant aquaculture systems represent highly effective productions sites for human food if proper plant and fish species are selected The present papers elucidates ways to novel aquaculture systems in which herbivorous fishes are raised by feeding them with plant biomass produced in the BIOCURE filters and presents the scheme of a modification which utilizes a plant species suitable also for human nutrition. Special attention is paid to the benefits of closed aquaculture system modules which may be integrated into bioregenerative life support systems of a higher complexity for, e. g.. lunar or planetary bases including some psychologiccal aspects of the introduction of animal protein production into plant-based life support systems. Moreover, the basic reproductive biological problems of aquatic animal breeding under reduced gravity are explained leading to a disposition of essential research programs in this context.

  1. Freshwater Mussels as Biological Sensors and Cyclers of Aquatic Nitrogen Constituents: An Experimental Investigation

    Science.gov (United States)

    Kruger, A.; Just, C. L.; Mudumbai, R.; Dasgupta, S.; Newton, T. J.; Durst, J.; Boddicker, M. D.; Diken, M. B.; Bril, J.; Baidoo-Williams, H. E.

    2011-12-01

    One of the most extensive manifestations of anthropogenic mismanagement of nitrogen is eutrophication of the Gulf of Mexico. Leaching and runoff transport nitrate compounds-excess agricultural fertilizer and animal waste-via the Mississippi River to the Gulf of Mexico. Phytoplankton then multiplies exponentially, and consumes most of the dissolved oxygen. This hypoxia kills fish and other organisms, leading to so-called dead zones in the Gulf that can cover 6,000-7,000 square miles. Dead zone mitigation plans call for coupling management actions with enhanced monitoring, modeling, and research on nitrogen delivery to, as well as processing within, the Mississippi River. Our vision is to create a biosensor network of native freshwater mussels in a major river to monitor, comprehend, and ultimately model key components of the nitrogen cycle. Native freshwater mussels are a guild of long-lived, suspension feeding bivalves that perform important ecological functions in aquatic systems. Mussels can influence nutrient cycling by transferring nutrients from the water column to the riverbed. A major problem for environmental scientists is that relatively little is known about the diurnal behaviors of freshwater mussels or the impacts these behaviors may have on the aquatic nitrogen cycle. Our multidisciplinary team is performing a series of laboratory experiments exploring the feasibility of using freshwater mussels as sensors of and capacitors for nitrates. For sensing, we place Hall-effect sensors on mussels to monitor the rhythmic opening and closing of their valves (gape). One shortcoming of previous work is that mussels were monitored in artificial conditions: glued fast in laboratory flumes, or tethered in constrained settings. To overcome this shortcoming, our team has built a mussel microhabitat with a constant river water feed stock, solar simulator, and a variety of water chemistry sensor. A main thrust of our work is to develop the technology to monitor mussel

  2. Axial allometry in a neutrally buoyant environment: effects of the terrestrial-aquatic transition on vertebral scaling.

    Science.gov (United States)

    Jones, K E; Pierce, S E

    2016-03-01

    Ecological diversification into new environments presents new mechanical challenges for locomotion. An extreme example of this is the transition from a terrestrial to an aquatic lifestyle. Here, we examine the implications of life in a neutrally buoyant environment on adaptations of the axial skeleton to evolutionary increases in body size. On land, mammals must use their thoracolumbar vertebral column for body support against gravity and thus exhibit increasing stabilization of the trunk as body size increases. Conversely, in water, the role of the axial skeleton in body support is reduced, and, in aquatic mammals, the vertebral column functions primarily in locomotion. Therefore, we hypothesize that the allometric stabilization associated with increasing body size in terrestrial mammals will be minimized in secondarily aquatic mammals. We test this by comparing the scaling exponent (slope) of vertebral measures from 57 terrestrial species (23 felids, 34 bovids) to 23 semi-aquatic species (pinnipeds), using phylogenetically corrected regressions. Terrestrial taxa meet predictions of allometric stabilization, with posterior vertebral column (lumbar region) shortening, increased vertebral height compared to width, and shorter, more disc-shaped centra. In contrast, pinniped vertebral proportions (e.g. length, width, height) scale with isometry, and in some cases, centra even become more spool-shaped with increasing size, suggesting increased flexibility. Our results demonstrate that evolution of a secondarily aquatic lifestyle has modified the mechanical constraints associated with evolutionary increases in body size, relative to terrestrial taxa. PMID:26679743

  3. Ecological limitations on aquatic mosquito predator colonization in the urban environment.

    Science.gov (United States)

    Carlson, John; Keating, Joseph; Mbogo, Charles M; Kahindi, Samuel; Beier, John C

    2004-12-01

    Urban malaria cases are becoming common in Africa as more people move into cities and industrialization proceeds. While many species of Anopheles mosquitoes vector malaria in rural areas, only a few are found within cities. The success of anthropophilic species in cities, such as members of the An. gambiae complex, may be explained by limitations on colonization by predator species in urban environments. Habitats that are temporal or structurally simple have lower predator survivorship in a variety of ecosystems, but these have not been investigated previously in an urban area. Areas within and around the Kenyan coastal town of Malindi were previously sampled for the presence of standing water using a geographic sampling strategy with probability proportional to size sampling of planned well-drained, unplanned poorly-drained, planned poorly-drained, unplanned well-drained, and peri-urban locations. Standing aquatic habitats in these areas were reassessed. During monthly sampling, presence/absence of mosquitoes and predator taxa were noted, as were ecological habitat variables: structural complexity and presence of water. Lambda statistics were calculated to associate predator guilds, habitat types, location variables, and ecological variables. All predator guilds found in habitats were strongly associated with habitat type, as were the structural complexity and temporal nature of the habitats. Types of habitat were heterogeneously distributed throughout Malindi, with swimming pools as a common habitat type in planned urban areas and tire track pools a common habitat type in peri-urban areas of Malindi. Predator colonization of aquatic habitats in Malindi was strongly influenced by habitat type, and not associated with location characteristics. Ecological variables were affected by the type of habitats, which are co-associated with planning and drainage in Malindi. While habitat types are distributed heterogeneously within Malindi, habitats with low predation

  4. Investigating hypoxia in aquatic environments: diverse approaches to addressing a complex phenomenon

    Directory of Open Access Journals (Sweden)

    J. Friedrich

    2013-08-01

    Full Text Available In this paper we synthesize the new knowledge on oxygen and oxygen-related phenomena in aquatic systems, resulting from the EU-FP7 project HYPOX ("In situ monitoring of oxygen depletion in hypoxic ecosystems of coastal and open seas, and land-locked water bodies", www.hypox.net. In view of the anticipated oxygen loss in aquatic systems due to eutrophication and climate change, HYPOX was set up to improve capacities to monitor hypoxia as well as to understand its causes and consequences. Temporal dynamics and spatial patterns of hypoxia were analysed in field studies in various aquatic environments, including the Baltic Sea, the Black Sea, Scottish and Scandinavian fjords, Ionian Sea lagoons and embayments, and in Swiss lakes. Examples of episodic and rapid (hours occurrences of hypoxia as well as seasonal changes in bottom-water oxygenation in stratified systems are discussed. Geologically-driven hypoxia caused by gas seepage is demonstrated. Using novel technologies, temporal and spatial patterns of water-column oxygenation, from basin-scale seasonal patterns to meter-scale submicromolar oxygen distributions were resolved. Existing multi-decadal monitoring data were used to demonstrate the imprint of climate change and eutrophication on long-term oxygen distributions. Organic and inorganic proxies were used to extend investigations on past oxygen conditions to centennial and even longer timescales not resolved by monitoring. The effects of hypoxia on faunal communities and biogeochemical processes were also addressed in the project. An investigation of benthic fauna is presented as an example of hypoxia-devastated benthic communities that slowly recover upon a reduction in eutrophication in a system where natural and anthropogenic hypoxia overlap. Biogeochemical investigations reveal that oxygen intrusions have a strong effect on microbially-mediated redox cycling of elements. Observations and modeling studies of the sediments demonstrate the

  5. Investigating hypoxia in aquatic environments: diverse approaches to addressing a complex phenomenon

    Science.gov (United States)

    Friedrich, J.; Janssen, F.; Aleynik, D.; Bange, H. W.; Boltacheva, N.; Çagatay, M. N.; Dale, A. W.; Etiope, G.; Erdem, Z.; Geraga, M.; Gilli, A.; Gomoiu, M. T.; Hall, P. O. J.; Hansson, D.; He, Y.; Holtappels, M.; Kirf, M. K.; Kononets, M.; Konovalov, S.; Lichtschlag, A.; Livingstone, D. M.; Marinaro, G.; Mazlumyan, S.; Naeher, S.; North, R. P.; Papatheodorou, G.; Pfannkuche, O.; Prien, R.; Rehder, G.; Schubert, C. J.; Soltwedel, T.; Sommer, S.; Stahl, H.; Stanev, E. V.; Teaca, A.; Tengberg, A.; Waldmann, C.; Wehrli, B.; Wenzhöfer, F.

    2014-02-01

    In this paper we provide an overview of new knowledge on oxygen depletion (hypoxia) and related phenomena in aquatic systems resulting from the EU-FP7 project HYPOX ("In situ monitoring of oxygen depletion in hypoxic ecosystems of coastal and open seas, and landlocked water bodies", http://www.hypox.net). In view of the anticipated oxygen loss in aquatic systems due to eutrophication and climate change, HYPOX was set up to improve capacities to monitor hypoxia as well as to understand its causes and consequences. Temporal dynamics and spatial patterns of hypoxia were analyzed in field studies in various aquatic environments, including the Baltic Sea, the Black Sea, Scottish and Scandinavian fjords, Ionian Sea lagoons and embayments, and Swiss lakes. Examples of episodic and rapid (hours) occurrences of hypoxia, as well as seasonal changes in bottom-water oxygenation in stratified systems, are discussed. Geologically driven hypoxia caused by gas seepage is demonstrated. Using novel technologies, temporal and spatial patterns of water-column oxygenation, from basin-scale seasonal patterns to meter-scale sub-micromolar oxygen distributions, were resolved. Existing multidecadal monitoring data were used to demonstrate the imprint of climate change and eutrophication on long-term oxygen distributions. Organic and inorganic proxies were used to extend investigations on past oxygen conditions to centennial and even longer timescales that cannot be resolved by monitoring. The effects of hypoxia on faunal communities and biogeochemical processes were also addressed in the project. An investigation of benthic fauna is presented as an example of hypoxia-devastated benthic communities that slowly recover upon a reduction in eutrophication in a system where naturally occurring hypoxia overlaps with anthropogenic hypoxia. Biogeochemical investigations reveal that oxygen intrusions have a strong effect on the microbially mediated redox cycling of elements. Observations and

  6. Multi-metal contamination with uranium trend impact on aquatic environment and consequences for fish immune system and adaptive responses

    Energy Technology Data Exchange (ETDEWEB)

    Le Guernic, A.; Gagnaire, B. [IRSN/PRP-ENV/SERIS/LECO (France); Sanchez, W. [Institut national de l' environnement industriel et des risques - INERIS (France); Betoulle, S. [Champagne Ardenne University (France)

    2014-07-01

    Human activities have conducted to an increase of concentrations of various metals in aquatic ecosystems, including uranium. Its extraction and use have been rapidly magnified because of its role in the nuclear fuel cycle. These activities have led to high concentrations of uranium in the aquatic environment and thus a potential risk to exposed organisms, including fish. Consequences can be observed through metabolic and physiological responses, called biomarkers. Some biomarkers are interesting in order to evaluate the effects of metal contamination, among other immunotoxicity markers, antioxidant defenses and genotoxicity. The aims of this study are: i) to investigate the effects of a multi-metal contamination on a fish, the three-spined stickleback, Gasterosteus aculeatus, and ii) to observe the adaptive capacity of fish due to a combination of stress (chemical stress and biological stress). To meet the first objective, six water bodies (ponds and lakes) located in two departments (Cantal and Haute-Vienne, France) were chosen according to their proximity to old uranium mines and to their levels of metal contamination related to chemical processes appeared during extraction. 240 three-spined sticklebacks were caged for 28 days in the six selected sites. A battery of biomarkers was measured in fish sampled after 14 and 28 of caging. The results for the Haute-Vienne department showed that caged fish in the pond with the highest uranium concentration (20 μg.L{sup -1}) presented the most DNA damage after 14 days of caging. Leukocyte phagocytosis (marker of immunotoxicity) of caged fish in this pond was lower at 14 days and greater at 28 days compared to other ponds without uranium. The multi-metal contamination negatively affected other parameters such as the condition index, oxidative activity, viability of lysosomal membrane and leukocytes distribution. In order to study the response of fish to a combined stress (chemical + biological) (objective ii), a second

  7. Multi-metal contamination with uranium trend impact on aquatic environment and consequences for fish immune system and adaptive responses

    International Nuclear Information System (INIS)

    Human activities have conducted to an increase of concentrations of various metals in aquatic ecosystems, including uranium. Its extraction and use have been rapidly magnified because of its role in the nuclear fuel cycle. These activities have led to high concentrations of uranium in the aquatic environment and thus a potential risk to exposed organisms, including fish. Consequences can be observed through metabolic and physiological responses, called biomarkers. Some biomarkers are interesting in order to evaluate the effects of metal contamination, among other immunotoxicity markers, antioxidant defenses and genotoxicity. The aims of this study are: i) to investigate the effects of a multi-metal contamination on a fish, the three-spined stickleback, Gasterosteus aculeatus, and ii) to observe the adaptive capacity of fish due to a combination of stress (chemical stress and biological stress). To meet the first objective, six water bodies (ponds and lakes) located in two departments (Cantal and Haute-Vienne, France) were chosen according to their proximity to old uranium mines and to their levels of metal contamination related to chemical processes appeared during extraction. 240 three-spined sticklebacks were caged for 28 days in the six selected sites. A battery of biomarkers was measured in fish sampled after 14 and 28 of caging. The results for the Haute-Vienne department showed that caged fish in the pond with the highest uranium concentration (20 μg.L-1) presented the most DNA damage after 14 days of caging. Leukocyte phagocytosis (marker of immunotoxicity) of caged fish in this pond was lower at 14 days and greater at 28 days compared to other ponds without uranium. The multi-metal contamination negatively affected other parameters such as the condition index, oxidative activity, viability of lysosomal membrane and leukocytes distribution. In order to study the response of fish to a combined stress (chemical + biological) (objective ii), a second

  8. Distribution and culturability of the uncultivated 'AGG58 cluster' of the Bacteroidetes phylum in aquatic environments.

    Science.gov (United States)

    O'Sullivan, Louise A; Fuller, Katherine E; Thomas, Ellen M; Turley, Carol M; Fry, John C; Weightman, Andrew J

    2004-03-01

    Members of the Bacteroidetes phylum are abundant in aquatic habitats when assessed by fluorescent in situ hybridisation and in some 16S rRNA gene libraries. In this study 16S rRNA gene clone libraries were constructed with bacterial primers that amplify Bacteroidetes sequences well (27F, 1492R) from coastal seawater near Plymouth (UK) during a phytoplankton bloom. Most of the clones (66%, 106/160) affiliated with the Bacteroidetes phylum, and of these 62% (66/106; or 41% 66/160 of the entire library) clustered with marine bacterioplankton clones env.agg58, Arctic97A-17, CF17, CF96 and CF101. This phylogenetic branch of Bacteroidetes was designated the 'AGG58 cluster', and its presence in various aquatic environments was investigated. Two pairs of AGG58-specific 16S rRNA-gene-targeted polymerase chain reaction (PCR) primers were designed and successfully used to detect the cluster in DNA extracts from three UK coastal seawater sites, and from freshwater River Taff epilithon. In addition, 600 putative Bacteroidetes strains were isolated from these sites on relatively high-nutrient agar media. AGG58 cluster specific probes were used to screen the amplified 16S rRNA gene products from the isolates, but no members of the AGG58 cluster were discovered. The least specific probe hybridised with one River Taff water isolate (RW262 NCIMB 13979) which formed a monophyletic group with the genera Crocinitomix, Brumimicrobium and Cryomorpha of the family Cryomorphaceae in the Bacteroidetes phylum. RW262 probably represents the first isolate of a new genus within this family. This study provides new evidence that the uncultivated AGG58 group is abundant, globally distributed, and can be rapidly detected with the new PCR primers described. PMID:19712324

  9. Use of Aeromonas spp. as General Indicators of Antimicrobial Susceptibility among Bacteria in Aquatic Environments in Thailand.

    Science.gov (United States)

    Usui, Masaru; Tagaki, Chie; Fukuda, Akira; Okubo, Torahiko; Boonla, Chanchai; Suzuki, Satoru; Seki, Kanako; Takada, Hideshige; Tamura, Yutaka

    2016-01-01

    Antimicrobials are widely used, not only for treating human infections, but also for treatment of livestock and in fish farms. Human habitats in Southeastern Asian countries are located in close proximity to aquatic environments. As such, the human populations within these regions are at risk of exposure to antimicrobial resistant bacteria, and thereby disseminating antimicrobial resistance genes (ARGs). In this study, we collected water samples from 15 sites (5 sites in Chao Phraya River, 2 sites at the mouth of Chao Phraya River, 3 sites in Ta Chin River, and 5 sites at city canals) and 12 sites (6 sites at city canals; 2 sites at chicken farms; 2 sites at pig farms; and 2 samples from sites at pig farms, which were subsequently treated at a biogas plant) in Thailand in 2013 and 2014, respectively. In total, 117 Aeromonas spp. were isolated from the water samples, and these organisms exhibited various antimicrobial susceptibility profiles. Notably, there was a significant correlation between the environmental concentration of tetracyclines and the rates of tetracycline resistance in the isolated Aeromonas spp.; however, both the concentration and rates of tetracycline resistance in samples derived from pig farms were higher than those of samples harvested from other aquatic environments. These findings suggest that the high concentrations of antimicrobials observed in these aquatic environments likely select for ARGs. Furthermore, they indicate that Aeromonas spp. comprise an effective marker for monitoring antimicrobial resistance in aquatic environments. PMID:27433156

  10. Use of Aeromonas spp. as General Indicators of Antimicrobial Susceptibility among Bacteria in Aquatic Environments in Thailand

    Science.gov (United States)

    Usui, Masaru; Tagaki, Chie; Fukuda, Akira; Okubo, Torahiko; Boonla, Chanchai; Suzuki, Satoru; Seki, Kanako; Takada, Hideshige; Tamura, Yutaka

    2016-01-01

    Antimicrobials are widely used, not only for treating human infections, but also for treatment of livestock and in fish farms. Human habitats in Southeastern Asian countries are located in close proximity to aquatic environments. As such, the human populations within these regions are at risk of exposure to antimicrobial resistant bacteria, and thereby disseminating antimicrobial resistance genes (ARGs). In this study, we collected water samples from 15 sites (5 sites in Chao Phraya River, 2 sites at the mouth of Chao Phraya River, 3 sites in Ta Chin River, and 5 sites at city canals) and 12 sites (6 sites at city canals; 2 sites at chicken farms; 2 sites at pig farms; and 2 samples from sites at pig farms, which were subsequently treated at a biogas plant) in Thailand in 2013 and 2014, respectively. In total, 117 Aeromonas spp. were isolated from the water samples, and these organisms exhibited various antimicrobial susceptibility profiles. Notably, there was a significant correlation between the environmental concentration of tetracyclines and the rates of tetracycline resistance in the isolated Aeromonas spp.; however, both the concentration and rates of tetracycline resistance in samples derived from pig farms were higher than those of samples harvested from other aquatic environments. These findings suggest that the high concentrations of antimicrobials observed in these aquatic environments likely select for ARGs. Furthermore, they indicate that Aeromonas spp. comprise an effective marker for monitoring antimicrobial resistance in aquatic environments. PMID:27433156

  11. A modelling framework for the transport, transformation and biouptake of manufactured nanoparticles in the aquatic environment

    Science.gov (United States)

    Lofts, Stephen; Keller, Virginie; Dumont, Egon; Williams, Richard; Praetorius, Antonia; von der Kammer, Frank

    2016-04-01

    The development of innovative new chemical products is a key aspect of the modern economy, yet society demands that such development is environmentally sustainable. Developing knowledge of how new classes of chemicals behave following release to the environment is key to understanding the hazards that will potentially result. Nanoparticles are a key example of a class of chemicals that have undergone a significant expansion in production and use in recent years and so there is a need to develop tools to predict their potential hazard following their deliberate or incidental release to the environment. Generalising the understanding of the environmental behaviour of manufactured nanoparticles in general is challenging, as they are chemically and physically diverse (e.g. metals, metal oxides, carbon nanotubes, cellulose, quantum dots). Furthermore, nanoparticles may be manufactured with capping agents to modify their desired behaviour in industrial applications; such agents may also influence their environmental behaviour. Also, nanoparticles may become significantly modified from their as-manufactured forms both prior to and after the point of environmental release. Tools for predicting nanoparticle behaviour and hazard need to be able to consider a wide range of release scenarios and aspects of nanoparticle behaviour in the environment (e.g. dissolution, transformation of capping agents, agglomeration and aggregation behaviour), where such behaviours are not shared by all types of nanoparticle. This implies the need for flexible, futureproofed tools capable of being updated to take new understanding of behavioural processes into account as such knowledge emerges. This presentation will introduce the NanoFASE model system, a multimedia modelling framework for the transport, transformation and biouptake of manufactured nanoparticles. The complete system will comprise atmospheric, terrestrial and aquatic compartments to allow holistic simulation of nanoparticles; this

  12. Worldwide occurrence and effects of antifouling paint booster biocides in the aquatic environment: a review.

    Science.gov (United States)

    Konstantinou, I K; Albanis, T A

    2004-04-01

    Organic booster biocides were recently introduced as alternatives to organotin compounds in antifouling products, after restrictions imposed on the use of tributyltin (TBT) in 1987. Replacement products are generally based on copper metal oxides and organic biocides. This ban has led to an increase in alternative coating products containing the above biocides. The most commonly used biocides in antifouling paints are: Irgarol 1051, diuron, Sea-nine 211, dichlofluanid, chlorothalonil, zinc pyrithione, TCMS (2,3,3,6-tetrachloro-4-methylsulfonyl) pyridine, TCMTB [2-(thiocyanomethylthio) benzothiazole], and zineb. Since 1993, several studies have demonstrated the presence of these biocides in European coastal environment as a result of their increased use. More recently, the presence of these biocides was also revealed in waters from Japan, United States, Singapore, Australia and Bermuda. This paper reviews the currently available data on the occurrence of these biocides in the aquatic environment. Some data dealing with the environmental fate, partitioning, behaviour and risk assessment of antifouling paint booster biocides are also reported in order to discuss the detected levels of contamination. PMID:14749112

  13. Pollution pathways of pharmaceutical residues in the aquatic environment on the island of Mallorca, Spain.

    Science.gov (United States)

    Rodríguez-Navas, Carlos; Björklund, Erland; Bak, Søren A; Hansen, Martin; Krogh, Kristine A; Maya, Fernando; Forteza, Rafael; Cerdà, Víctor

    2013-07-01

    This work determines the principal environmental pollution pathways of pharmaceuticals on the island of Mallorca (Spain). The evaluation was made on the basis of the quantification of pharmaceutical residues by liquid chromatography-tandem mass spectrometry in several environmental water samples, including wastewater-treatment plant effluents, municipal solid waste landfill leachates, groundwater (GW), and marine water. An overall set of 19 pharmaceuticals has been identified in the environment of the 27 human pharmaceuticals investigated in this study. WWTP effluents are the main source of discharge of the pharmaceuticals into the aquatic environment. The data indicate that reuse of treated domestic wastewater for irrigation (which supplies some 30 % of the total water demand in Mallorca) contributes to the contamination of GW. In addition, leaching from landfills is identified as another, but minor, possible source of introduction of pharmaceuticals to GW aquifers. Finally, WWTP effluents ending in the Mediterranean Sea, primarily highly urbanized coastal areas, cause pharmaceutical residues to occur in marine water bodies. PMID:23440447

  14. Investigation of oil drilling impacts to aquatic habitat resources: In Situ biological assessment of the photoinduced toxicity of environmental releases of crude oil

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This study proposed a biological assessment of a recent crude oil spill for potential impacts to aquatic resources due to petroleum hydrocarbon wastes. The...

  15. Application of liquid chromatography-tandem mass spectrometry in quantitative bioanalyses of organic molecules in aquatic environment and organisms.

    Science.gov (United States)

    Bussy, Ugo; Li, Ke; Li, Weiming

    2016-05-01

    Analytical methods using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) for the simultaneous determination of metabolites or contaminants (or both) in various tissues of aquatic organisms and in the aquatic environment have received increasing attention in the last few years. This review discusses the findings relevant to such procedures published between 2005 and 2015. The aim is to evaluate the advantages, restrictions, and performances of the procedures from sample preparation to mass spectrometry measurement. To support these discussions, a general knowledge on LC-MS/MS is also provided. PMID:26996906

  16. Reactivity and transfer of tributyl-tin and mercury in aquatic environments; Etude de la reactivite et du transfert du tributyletain et du mercure dans les environnements aquatiques

    Energy Technology Data Exchange (ETDEWEB)

    Tessier, E.

    2004-12-15

    Aquatic ecosystems are particularly affected by tributyl-tin (TBT) and mercury (Hg) chronic contamination. These micro-pollutants are ubiquitous and persistent and occurred at trace level, likely to drastically impair aquatic environments. TBT and Hg biogeochemical cycles are driven by transformation and transfer mechanisms between the different environmental compartments. These natural processes have been studied in details by using novel analytical methods and environmental design to improve the risk assessment. The first part of this work focus on the mechanistic study of TBT and Hg reactivity and transfer in reconstituted aquatic ecosystems. These experiments involve both state-of-the-art analytical speciation techniques, partly based on quantification by isotopic dilution and experimental tools simulating the environmental conditions. Kinetics of TBT and Hg distribution (adsorption, bioaccumulation, biodegradation, clearance) have been simultaneously characterized in all compartments of the microcosms presenting a simple biological organization. In a second step, volatilization kinetics of TBT at real interfaces have been studied to assess the potential remobilization and elimination pathways of butyl-tin compounds. Finally, in a third part, stable isotopic tracers of Hg have been employed to discriminate and quantify the coupled methylation and demethylation kinetics in estuarine sediments, by forcing different environmental factors (oxygenation, microbial activity). (author)

  17. LADTAP-2, Organ Doses to Man and Other Biota from Aquatic Environment

    International Nuclear Information System (INIS)

    1 - Description of problem or function: LADTAP2 performs environmental dose analyses for releases of liquid effluents from light-water nuclear power plants into surface waters during routine operation. The analyses estimate radiation doses to individuals, population groups, and biota from ingestion (aquatic foods, water, and terrestrial irrigated foods) and external exposure (shoreline, swimming, and boating) pathways. The calculated doses provide information for National Environmental Policy Act (NEPA) evaluations and for determining compliance with Appendix I of 10 CFR 50 (the 'ALARA' philosophy). The program consists of a hydrologic model chosen to represent mixing in the effluent impoundment system and the receiving surface waters and the exposure pathway models which estimate exposure of selected groups at various water usage locations in the environment. Two types of population doses are calculated. An ALARA analysis is performed based on exposure of people within 50 miles of the site, and a NEPA analysis is performed based on exposure of the entire U.S. population to effluents from the site. A population-dose analysis prepared in the form of a cost-benefit table presents the total-body and thyroid doses from each radionuclide released and the population doses (total-body and thyroid) per curie of each radionuclide released. 2 - Method of solution: The impoundment system is represented by one of four hydrologic models: direct release to the receiving water, linear flow with no mixing (the plug-flow model), linear flow through the impoundment with partial recirculation through the reactor (the partially mixed model), or complete mixing in the impoundment with partial recirculation through the reactor (the completely mixed model). The last three account for radiological decay during transit through the impoundment system. Optional models are available to estimate dilution in nontidal rivers and near-shore lake environments. The consequence calculation part of

  18. Experimental Design and Analysis of the Fate of Nanoparticulate Titanium Dioxide in Aquatic Environment

    Science.gov (United States)

    Xiang, Chengcheng

    The increase in the production and use of engineered nanomaterials has been considered to result in potential environmental risks and health issues. Of the commonly used nanomaterials, TiO2 has raised intensive concern due to its wide-spread application in food, drugs, cosmetics, catalysis, ultraviolet blocker, and sorbents for water treatment, etc. It is believed that TiO2 nanomaterials possess distinct transport, transfer and toxicity in the aquatic environment. This research applies the design of experiments methodology to investigate the fate of engineered TiO2 nanoparticles with various functional groups in the simulated aquatic environment. Multiple linear regression models were used to analyze the experimental fate data. The engineered TiO2 NPs with -CH3, -SH, -OH, -COOH and -SO3H functional groups were prepared by the surface silanization, and characterized by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The surface charge, aggregation and surface chemistry of engineered TiO2 NPs were investigated by dynamic (electrophoretic) light scattering. Results obtained from the multiple linear regression model show that the pH, the ionic strength and the cation type affect the surface charge, aggregation, and adsorption capability in individual and associated forms. Moreover, the surface functional group on TiO2 NPs surface dominates the fate in the simulated aquatic environment. Especially, the zeta potential of TiO2 NPs decreased with the increase of pH value in low salt concentration, whereas SO3H-, COOH-, OH- and SH- TiO2 NPs slightly increased when pH increased. The zeta potential of TiO2 NPs also increased with the increasing salt concentration at the whole pH range and COOH-TiO2 NPs are more sensitive to the salt concentration in the zeta potential. Furthermore, the zeta potential of TiO2 NPs in solutions containing CaCl2 is higher than that in NaCl. The hydrodynamic size was little affected by the pH value or had

  19. Sulfonamide and tetracycline resistance genes in total- and culturable-bacterial assemblages in South African aquatic environments

    OpenAIRE

    Satoru eSuzuki; Mitsuko eOgo; Tatsuya eKoike; Hideshige eTakada; Brent eNewman

    2015-01-01

    Antibiotic resistant bacteria (ARB) are ubiquitous in the natural environment. The introduction of effluent derived antibiotic resistance genes (ARGs) into aquatic environments is of concern in the spreading of genetic risk. This study showed the prevalence of sulfonamide and tetracycline resistance genes, sul1, sul2, sul3 and tet(M), in the total bacterial assemblage and colony forming bacterial assemblage in river and estuarine water and sewage treatment plants (STP) in South Africa. There ...

  20. Sulfonamide and tetracycline resistance genes in total- and culturable-bacterial assemblages in South African aquatic environments

    OpenAIRE

    Suzuki, Satoru; Ogo, Mitsuko; Koike, Tatsuya; Takada, Hideshige; Newman, Brent

    2015-01-01

    Antibiotic resistant bacteria are ubiquitous in the natural environment. The introduction of effluent derived antibiotic resistance genes (ARGs) into aquatic environments is of concern in the spreading of genetic risk. This study showed the prevalence of sulfonamide and tetracycline resistance genes, sul1, sul2, sul3, and tet(M), in the total bacterial assemblage and colony forming bacterial assemblage in river and estuarine water and sewage treatment plants (STP) in South Africa. There was no ...

  1. Hazardous materials in aquatic environments of the Mississippi River Basin. Annual technical report, December 30, 1992--December 29, 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-31

    Tulane and Xavier Universities have singled out the environment as a major strategic focus for research and training for now and by the year 2000. In December, 1992, the Tulane/Xavier CBR was awarded a five year grant to study pollution in the Mississippi River system. The ``Hazardous Materials in Aquatic Environments of the Mississippi River Basin`` project is a broad research and education program aimed at elucidating the nature and magnitude of toxic materials that contaminate aquatic environments of the Mississippi River Basin. Studies include defining the complex interactions that occur during the transport of contaminants, the actual and potential impact on ecological systems and health, and the mechanisms through which these impacts might be remediated. The Mississippi River Basin represents a model system for analyzing and solving contamination problems that are found in aquatic systems world-wide. These research and education projects are particularly relevant to the US Department of Energy`s programs aimed at addressing aquatic pollution problems associated with DOE National Laboratories. First year funding supported seven collaborative cluster projects and twelve initiation projects. This report summarizes research results for period December 1992--December 1993.

  2. Diversity and abundance of aquatic macroinvertebrates in a lotic environment in Midwestern São Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    Gabriel Lucas Bochini

    2009-04-01

    Full Text Available This study analyzed the diversity and abundance of an aquatic macroinvertebrate community in the Vargem Limpa stream located in Bauru, Midwestern São Paulo State, and characterized the water quality based on biological parameters. The sampling was carried out during the rain season (December, 2004. It was analyzed and identified 3,068 organisms belonging to 9 macroinvertebrate families. The system showed low richness and diversity of organisms in response to water quality.

  3. Numerical modelling of distribution the discharged heat water from thermal power plant on the aquatic environment

    Science.gov (United States)

    Issakhov, Alibek

    2016-06-01

    The paper presents a mathematical model of distribution the discharged heat water from thermal power plant under various operational capacities on the aquatic environment. It was solved by the Navier-Stokes and temperature equations for an incompressible fluid in a stratified medium were based on the splitting method by physical parameters which approximated by the finite volume method. The numerical solution of the equation system was divided into four stages. At the first step it was assumed that the momentum transfer carried out only by convection and diffusion. While the intermediate velocity field was solved by 5-step Runge-Kutta method. At the second stage, the pressure field was solved by found the intermediate velocity field. Whereas Poisson equation for the pressure field was solved by Jacobi method. The third step assumes that the transfer was carried out only by pressure gradient. Finally the fourth step of the temperature equation was also solved as motion equations, with 5-step Runge-Kutta method. The algorithm was parallelized on high-performance computer. The obtained numerical results of three-dimensional stratified turbulent flow were compared with experimental data. What revealed qualitatively and quantitatively approximately the basic laws of hydrothermal processes occurring in the reservoir-cooler.

  4. Thresholds of toxicological concern for endocrine active substances in the aquatic environment.

    Science.gov (United States)

    Gross, Melanie; Daginnus, Klaus; Deviller, Genevieve; de Wolf, Watze; Dungey, Stephen; Galli, Corrado; Gourmelon, Anne; Jacobs, Miriam; Matthiessen, Peter; Micheletti, Christian; Nestmann, Earle; Pavan, Manuela; Paya-Perez, Ana; Ratte, Hans-Toni; Safford, Bob; Sokull-Klüttgen, Birgit; Stock, Frauke; Stolzenberg, Hans-Christian; Wheeler, James; Willuhn, Marc; Worth, Andrew; Comenges, Jose Manuel Zaldivar; Crane, Mark

    2010-01-01

    The threshold of toxicological concern (TTC) concept proposes that an exposure threshold value can be derived for chemicals, below which no significant risk to human health or the environment is expected. This concept goes further than setting acceptable exposure levels for individual chemicals, because it attempts to set a de minimis value for chemicals, including those of unknown toxicity, by taking the chemical's structure or mode of action (MOA) into consideration. This study examines the use of the TTC concern concept for endocrine active substances (EAS) with an estrogenic MOA. A case study formed the basis for a workshop of regulatory, industry and academic scientists held to discuss the use of the TTC in aquatic environmental risk assessment. The feasibility and acceptability, general advantages and disadvantages, and the specific issues that need to be considered when applying the TTC concept for EAS in risk assessment were addressed. Issues surrounding the statistical approaches used to derive TTCs were also discussed. This study presents discussion points and consensus findings of the workshop. PMID:19558199

  5. Research Trends in Emerging Contaminants on the Aquatic Environments of Tanzania

    Directory of Open Access Journals (Sweden)

    H. Miraji

    2016-01-01

    Full Text Available The continuity for discovery and production of new chemicals, allied products, and uses has currently resulted into generation of recent form of contaminants known as Emerging Contaminants (ECs. Once in the aquatic environment ECs are carcinogenic and cause other threats to both human’s and animals’ health. Due to their effects this study was aimed at investigating research trends of ECs in Tanzania. Findings revealed that USA and EU countries were leading in ECs researches, little followed by Asia, South Africa, and then Zambia. Only few guidelines from USA-EPA, WHO, Canada, and Australia existed. Neither published guidelines nor regulations for ECs existed in Tanzania; rather only the occurrence of some disinfection by-products and antibiotics was, respectively, reported in Arusha and Dar es Salaam, Tanzania. As these reports had a limited coverage of ECs, henceforth, these findings constitute the first-line reference materials for ECs research in Tanzania which shall be useful for future monitoring and regulation planning.

  6. Influence of humic-acid complexing on the mobility of Americium in the soil aquatic environment

    International Nuclear Information System (INIS)

    Diffusion data indicate the Am, Cm and Np migrate 1.2, 0.8, and 26 centimeters, respectively, in a thousand years. Thus, excluding mass transport by moving water or wind, actinide elements, such as Cm, Am, and Np that find their way to the soil-aquatic environment are relatively immobile. Measured diffusion coefficients, corrected for distribution between the aqueous and soil phases, tortuosity, negative absorption, and relative fluidity are in reasonable agreement with aqueous diffusion coefficients. However, agreement depends strongly on measurement method used to determine distribution ratios. Two sets of experiments with 241Am and 152Eu tracers have been done to measure distribution ratios as a function of the aqueous humic acid concentration. In the first experiments the solid phase was kaolinite and in the second series of distribution ratios were measured with Burbank sandy loam. Both of these experiments indicated that Am(III) and Eu(III) form very strong humic acid complexes with formation constants of approximately 105. Additional experiments are being done to establish the average number of Am(III)s or Eu(III)s bound to the humic acid polymer

  7. Stable hydrogen and carbon isotopic compositions of biogenic methanes from several shallow aquatic environments

    International Nuclear Information System (INIS)

    Stable hydrogen (δD) and carbon (δ/sup 13/C) isotopic compositions of methane gas bubbles formed in the sediments of several shallow aquatic environments were measured and found to range from -3460/oo to -2630/oo and from -75.00/oo to -51.50/oo, respectively. Evaluation of the δD data with a previously published model implies that acetate dissimilation accounts for about 50% to 80% of the total methane production. δD-CH/sub 4/ and δ/sup 13/C-CH/sub 4/ are generally inversely correlated; this indicates that the observed isotopic variation is not solely due to differential methane oxidation. δ/sup 13/C-CH/sub 4/ values reported in this paper imply that methane produced in these sediments is generally substantially more /sup 13/C-depleted than the estimated average atmospheric methane source. Methane with a δD near the estimated atmospheric source average is produced in some of these sediments; this apparent agreement may be fortuitous as few relevant data are available

  8. Bioaerosol emissions from open microalgal processes and their potential environmental impacts: what can be learned from natural and anthropogenic aquatic environments?

    Science.gov (United States)

    Sialve, Bruno; Gales, Amandine; Hamelin, Jérôme; Wery, Nathalie; Steyer, Jean-Philippe

    2015-06-01

    Open processes for microalgae mass cultivation and/or wastewater treatment present an air-water interface. Similarly to other open air-aquatic environments, they are subject to contamination, but as such, they also represent a source of bioaerosols. Indeed, meteorological, physico-chemical and biological factors cause aerial dispersion of the planktonic community. Operating conditions like liquid mixing or gas injection tend to both enhance microbial activity, as well as intensify aerosolization. Bacteria, virus particles, fungi and protozoa, in addition to microalgae, are all transient or permanent members of the planktonic community and can thus be emitted as aerosols. If they should remain viable, subsequent deposition on various habitats could instigate their colonization of other environments and the potential expression of their ecological function. PMID:25845483

  9. TAME - the terrestrial-aquatic model of the environment: model definition

    Energy Technology Data Exchange (ETDEWEB)

    Klos, R.A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Mueller-Lemans, H. [Tergoso AG fuer Umweltfragen, Sargans (Switzerland); Dorp, F. van [Nationale Genossenschaft fuer die Lagerung Radioaktiver Abfaelle (NAGRA), Baden (Switzerland); Gribi, P. [Colenco AG, Baden (Switzerland)

    1996-10-01

    TAME - the Terrestrial-Aquatic Model of the Environment is a new computer model for use in assessments of the radiological impact of the release of radionuclides to the biosphere, following their disposal in underground waste repositories. Based on regulatory requirements, the end-point of the calculations is the maximum annual individual dose to members of a hypothetical population group inhabiting the biosphere region. Additional mid- and end-points in the TAME calculations are dose as function of time from eleven exposure pathways, foodstuff concentrations and the distribution of radionuclides in the modelled biosphere. A complete description of the mathematical representations of the biosphere in TAME is given in this document, based on a detailed review of the underlying conceptual framework for the model. Example results are used to illustrate features of the conceptual and mathematical models. The end-point of dose is shown to be robust for the simplifying model assumptions used to define the biosphere for the example calculations. TAME comprises two distinct sub-models - one representing the transport of radionuclides in the near-surface environment and one for the calculation of dose to individual inhabitants of that biosphere. The former is the result of a detailed review of the modelling requirements for such applications and is based on a comprehensive consideration of all features, events and processes (FEPs) relevant to Swiss biospheres, both in the present-day biosphere and in potential future biosphere states. Representations of the transport processes are derived from first principles. Mass balance for water and solid material fluxes is used to determine the rates of contaminant transfer between components of the biosphere system. The calculation of doses is based on existing representations of exposure pathways and draws on experience both from Switzerland and elsewhere. (author) figs., tabs., refs.

  10. Trace enrichment of metal ions in aquatic environments by Saccharomyces cerevisiae.

    Science.gov (United States)

    Mapolelo, M; Torto, N

    2004-09-01

    Sorption properties of baker's yeast cells, characterised as Saccharomyces cerevisiae were evaluated for trace enrichment of metal ions: Cd(2+), Cr(3+), Cr(6+), Cu(2+), Pb(2+) and Zn(2+) from aqueous environments. Metal concentration was determined by flame atomic absorption spectrometry (FAAS). Parameters affecting metal uptake such as solution pH, incubation time, amount of yeast biomass and effect of glucose concentration (energy source) were optimised. Further studies were carried out to evaluate the effects on metal uptake after treating yeast with glucose as well as with an organic solvent. The results showed that trace enrichment of the metals under study with yeast, depends upon the amount of yeast biomass, pH and incubation time. Treatment of yeast cells with 10-20mM glucose concentration enhanced metal uptake with exception to Cr(6+), whose metal enrichment capacity decreased at glucose concentration of 60mM. Of the investigated organic solvents THF and DMSO showed the highest and lowest capacity, respectively, to enhance metal uptake by yeast cells. Trace enrichment of metal ions from stream water, dam water, treated wastewater from a sewage plant and wastewater from an electroplating plant achieved enrichment factors (EF) varying from 1 to 98, without pre-treatment of the sample. pH adjustment further enhanced the EF for all samples. The results from these studies demonstrate that yeast is a viable trace metal enrichment media that can be used freely suspended in solution to achieve very high EF in aquatic environments. PMID:18969566

  11. TAME - the terrestrial-aquatic model of the environment: model definition

    International Nuclear Information System (INIS)

    TAME - the Terrestrial-Aquatic Model of the Environment is a new computer model for use in assessments of the radiological impact of the release of radionuclides to the biosphere, following their disposal in underground waste repositories. Based on regulatory requirements, the end-point of the calculations is the maximum annual individual dose to members of a hypothetical population group inhabiting the biosphere region. Additional mid- and end-points in the TAME calculations are dose as function of time from eleven exposure pathways, foodstuff concentrations and the distribution of radionuclides in the modelled biosphere. A complete description of the mathematical representations of the biosphere in TAME is given in this document, based on a detailed review of the underlying conceptual framework for the model. Example results are used to illustrate features of the conceptual and mathematical models. The end-point of dose is shown to be robust for the simplifying model assumptions used to define the biosphere for the example calculations. TAME comprises two distinct sub-models - one representing the transport of radionuclides in the near-surface environment and one for the calculation of dose to individual inhabitants of that biosphere. The former is the result of a detailed review of the modelling requirements for such applications and is based on a comprehensive consideration of all features, events and processes (FEPs) relevant to Swiss biospheres, both in the present-day biosphere and in potential future biosphere states. Representations of the transport processes are derived from first principles. Mass balance for water and solid material fluxes is used to determine the rates of contaminant transfer between components of the biosphere system. The calculation of doses is based on existing representations of exposure pathways and draws on experience both from Switzerland and elsewhere. (author) figs., tabs., refs

  12. Effect-directed analysis supporting monitoring of aquatic environments--An in-depth overview.

    Science.gov (United States)

    Brack, Werner; Ait-Aissa, Selim; Burgess, Robert M; Busch, Wibke; Creusot, Nicolas; Di Paolo, Carolina; Escher, Beate I; Mark Hewitt, L; Hilscherova, Klara; Hollender, Juliane; Hollert, Henner; Jonker, Willem; Kool, Jeroen; Lamoree, Marja; Muschket, Matthias; Neumann, Steffen; Rostkowski, Pawel; Ruttkies, Christoph; Schollee, Jennifer; Schymanski, Emma L; Schulze, Tobias; Seiler, Thomas-Benjamin; Tindall, Andrew J; De Aragão Umbuzeiro, Gisela; Vrana, Branislav; Krauss, Martin

    2016-02-15

    Aquatic environments are often contaminated with complex mixtures of chemicals that may pose a risk to ecosystems and human health. This contamination cannot be addressed with target analysis alone but tools are required to reduce this complexity and identify those chemicals that might cause adverse effects. Effect-directed analysis (EDA) is designed to meet this challenge and faces increasing interest in water and sediment quality monitoring. Thus, the present paper summarizes current experience with the EDA approach and the tools required, and provides practical advice on their application. The paper highlights the need for proper problem formulation and gives general advice for study design. As the EDA approach is directed by toxicity, basic principles for the selection of bioassays are given as well as a comprehensive compilation of appropriate assays, including their strengths and weaknesses. A specific focus is given to strategies for sampling, extraction and bioassay dosing since they strongly impact prioritization of toxicants in EDA. Reduction of sample complexity mainly relies on fractionation procedures, which are discussed in this paper, including quality assurance and quality control. Automated combinations of fractionation, biotesting and chemical analysis using so-called hyphenated tools can enhance the throughput and might reduce the risk of artifacts in laboratory work. The key to determining the chemical structures causing effects is analytical toxicant identification. The latest approaches, tools, software and databases for target-, suspect and non-target screening as well as unknown identification are discussed together with analytical and toxicological confirmation approaches. A better understanding of optimal use and combination of EDA tools will help to design efficient and successful toxicant identification studies in the context of quality monitoring in multiply stressed environments. PMID:26779957

  13. Aquatic Environment, Housing, and Management in the Eighth Edition of the Guide for the Care and Use of Laboratory Animals: Additional Considerations and Recommendations

    OpenAIRE

    Mason, Timothy J.; Matthews, Monte

    2012-01-01

    The eighth edition of the Guide for the Care and Use of Laboratory Animals recognizes the widespread use of aquatic and semiaquatic research animals by including, among other references, an entire section on aquatic animals in its chapter on environment, housing, and management. Recognizing the large number of aquatic and semiaquatic species used in research and the inherent diversity in animal needs, the Guide refers the reader to texts and journal reviews for specific recommendations and su...

  14. Evaluation of removal efficiency of 2-chlorophenol in aquatic environments by modified fly ash

    Directory of Open Access Journals (Sweden)

    Mohammad Malakootian

    2015-12-01

    Full Text Available Background: Chlorophenols are classified as priority toxic pollutants. These acidic organic compounds present a serious potential hazard for human health and aquatic life. Chlorophenols accumulate in water, soil and air due to high stability, and impart an unpleasant taste and odor to drinking water and can exert negative effects on different biological processes. Among the different methods of removal, adsorption process by low price adsorbents, such as fly ash (FA is common. Therefore, in this study, the effects of oxidation of FA as modified adsorbent were investigated when the adsorption of 2-chlorophenol (2-CP was increased. Methods: This experimental study was conducted from March to September of 2013. FA obtained from Zarand power plant (located in Kerman province was oxidized with potassium permanganate. Effective factors on the oxidation of FA, such as temperature, oxidation time and concentrations of oxidizers were optimized. Raw sewage of Zarand coal washing plant was tested under optimal conditions. All tests were carried out according to the standard methods book for the examination of water and wastewater. Results: Optimal condition for the preparation of oxidized FA was obtained at 70°C, 1 hour, and 1 mM of potassium permanganate concentration. The absorber obtained was able to remove 96.22% of 2-CP under optimized conditions (pH=3, 2 hours, adsorbent dose 0.8 g and room temperature. The removal efficiency of the real wastewater under optimal conditions was 82.1%. Conclusion: Oxidized FA can be used for the removal of this pollutant from industry wastewater due to its high efficiency of removal in real wastewater, it is easy and inexpensive to prepare and could modify the sorbent.

  15. The Interplay of Biology and the Environment Broadly Defined

    OpenAIRE

    Diamond, Adele

    2009-01-01

    This special section of Developmental Psychology contains articles on the interplay of biology and the environment, broadly defined, that have the potential to change or challenge how developmental psychologists think. Topics include how experience affects gene expression; how genes affect how the environment is experienced and what effect the environment has; interactions between the environment and the presence or absence of early brain damage; motor neurons and the understanding of others’...

  16. Biological Production in Lakes. Physical Processes in Terrestrial and Aquatic Ecosystems, Ecological Processes.

    Science.gov (United States)

    Walters, R. A.; Carey, G. F.

    These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. Primary production in aquatic ecosystems is carried out by phytoplankton, microscopic plants…

  17. Origin, causes and effects of increased nitrite concentrations in aquatic environments

    NARCIS (Netherlands)

    Philips, S.; Laanbroek, H.J.; Verstraete, W.

    2002-01-01

    Literature frequently mentions increased nitrite concentrations along with its inhibitory effect towards bacteria and aquatic life. Nitrite accumulation has been studied for decades, and although numerous causal factors have already been commented on in literature, the mechanism of nitrite accumulat

  18. IMPLICATIONS TO THE AQUATIC ENVIRONMENT OF POLYNUCLEAR AROMATIC HYDROCARBONS LIBERATED FROM NORTHERN GREAT PLAINS COAL

    Science.gov (United States)

    The effects of leaching processes upon Western Great Plains coal was investigated to ascertain the potential impact of the organic components on aquatic organisms. Acute and chronic toxicity testing of coal leachate indicated no lipophilic fraction containing polynuclear aromatic...

  19. Ultrafast Excited-State Dynamics in Biological Environments

    OpenAIRE

    Fürstenberg, Alexandre; Vauthey, Eric

    2007-01-01

    We discuss and illustrate by several examples how the ultrafast excited-state dynamics of a chromophore can be altered when changing its environment from a homogenous solution to a biological molecule such as proteins or nucleic acids.

  20. Use of Aeromonas spp. as general indicators of antimicrobial susceptibility among bacteria in aquatic environments in Thailand

    OpenAIRE

    Masaru eUsui; Chie eTagaki; Akira eFukuda; Torahiko eOkubo; Chanchai eBoonla; Satoru eSuzuki; Kanako eSeki; Hideshige eTakada; Yutaka eTamura

    2016-01-01

    Antimicrobials are widely used, not only for treating human infections, but also for treatment of livestock and in fish farms. Human habitats in Southeastern Asian countries are located in close proximity to aquatic environments. As such, the human populations within these regions are at risk of exposure to antimicrobial resistant bacteria (ARB), and thereby disseminating antimicrobial resistance genes (ARGs). In this study, we collected water samples from 15 sites (5 sites in Chao Phraya Riv...

  1. Long-Term Sorption of Metals Is Similar among Plastic Types: Implications for Plastic Debris in Aquatic Environments

    OpenAIRE

    Rochman, Chelsea M.; Hentschel, Brian T.; Teh, Swee J.

    2014-01-01

    Concerns regarding plastic debris and its ability to accumulate large concentrations of priority pollutants in the aquatic environment led us to quantify relationships between different types of mass-produced plastic and metals in seawater. At three locations in San Diego Bay, we measured the accumulation of nine targeted metals (aluminum, chromium, manganese, iron, cobalt, nickel, zinc, cadmium and lead) sampling at 1, 3, 6, 9 and 12 months, to five plastic types: polyethylene terephthalate ...

  2. Use of Quantitative Real-Time PCR for Direct Detection of Serratia marcescens in Marine and Other Aquatic Environments

    OpenAIRE

    Joyner, Jessica; Wanless, David; Sinigalliano, Christopher D.; Erin K Lipp

    2014-01-01

    Serratia marcescens is the etiological agent of acroporid serratiosis, a distinct form of white pox disease in the threatened coral Acropora palmata. The pathogen is commonly found in untreated human waste in the Florida Keys, which may contaminate both nearshore and offshore waters. Currently there is no direct method for detection of this bacterium in the aquatic or reef environment, and culture-based techniques may underestimate its abundance in marine waters. A quantitative real-time PCR ...

  3. Preliminary studies of quality assessment of aquatic environments from Cluj suburban areas, based on some invertebrates bioindicators and chemical indicators

    OpenAIRE

    Gheorghe Stan; Laurenţiu C. Stoian; A. Bianca Badea; Andrea Gagyi-Palffy

    2010-01-01

    Systematic categories of invertebrates bioindicators correlated with some chemical parameters,were an effective way to characterize the quality of lotic (Someş River) and lentic (Lake Gilău) aquatic environment from Cluj-Napoca area. Invertebrate fauna was represented by species belonging to the following dominant systematic categories: Nematoda, Annelida, Crustacea and Insecta. This paper containsalso some preliminary data on the bioindicators species belonging to Protozoa phylum. Dominant g...

  4. The Effects of Dissolved Organic Matter on Pollutant Removal and Formation in Aquatic Environment: From Stormwater to Drinking Water

    OpenAIRE

    Hsu, Meng-Horng

    2012-01-01

    Hydrophobic organic pollutants (HOPs), such as polyaromatic hydrocarbons primarily from automobile exhausts and dissolved organic matter (DOM) are ubiquitous in the aquatic environment. The association between DOM and HOPs as a bound interaction of DOM-HOPs minimizes the bioavailability of free HOPs and their potential health effects. In addition, DOM is also the precursor of disinfection by-products involving the disinfection treatment processes.It is very important to understand the relat...

  5. Chemical calibration, performance, validation and applications of the polar organic chemical integrative sampler (POCIS) in aquatic environments

    OpenAIRE

    Morin, N.; Miège, C.; Coquery, M.; Randon, J.

    2012-01-01

    POCIS (Polar Organic Chemical Integrative Sampler) is a relatively recent integrative sampler developed to trap hydrophilic organic micropollutants in aquatic environments. Nevertheless, at present, there is no review dealing specifically with this tool. The aim of this paper was to compile information from numerous references based on POCIS in order to discuss on the evaluation of time-weighted average concentrations (calibration methods, sampling rates, performance and reference compounds&#...

  6. Cosmet'eau -Changes in the personal care product consumption practices: from whistle-blowers to impacts on aquatic environments

    OpenAIRE

    Bressy, Adèle; Carré, Catherine; Caupos, Émilie; De Gouvello, Bernard; Deroubaix, José-Frédéric; Deutsch, Jean-Claude; Mailler, Romain; Marconi, Anthony; Neveu, Pascale; Paulic, Laurent; Pichon, Sébastien; Rocher, Vincent; Severin, Irina; SOYER, Mathilde; Moilleron, Régis

    2016-01-01

    International audience The Cosmet'eau project (2015-2018) investigates the " changes in the personal care product (PCP) consumption practices: from whistle-blowers to impacts on aquatic environments. " In this project, the example of PCPs will be used to understand how public health concerns related to micropollutants can be addressed by public authorities – including local authorities –, industries and consumers. The project aims to characterize the possible changes in PCP consumption pra...

  7. Determination of Primary Spectral Bands for Remote Sensing of Aquatic Environments

    Directory of Open Access Journals (Sweden)

    MingXia He

    2007-12-01

    the spectral curve, and thus maximizes the potential of accurately deriving properties of the water column and/or bottom of various aquatic environments with a multi-band sensor.

  8. Interaction of mining activities and aquatic environment: A review from Greek mine sites.

    Science.gov (United States)

    Vasileiou, Eleni; Kallioras, Andreas

    2016-04-01

    In Greece a significant amount of mineral and ore deposits have been recorded accompanied by large industrial interest and a long mining history. Today many active and/or abandoned mine sites are scattered within the country; while mining activities take place in different sites for exploiting various deposits (clay, limestone, slate, gypsum, kaolin, mixed sulphide ores (lead, zinc, olivine, pozzolan, quartz lignite, nickel, magnesite, aluminum, bauxite, gold, marbles etc). The most prominent recent ones are: (i) the lignite exploitation that is extended in the area of Ptolemais (Western Macedonia) and Megalopolis (Central Peloponnese); and (ii) the major bauxite deposits located in central Greece within the Parnassos-Ghiona geotectonic zone and on Euboea Island. In the latter area, significant ores of magnesite were exploited and mixed sulphide ores. Centuries of intensive mining exploitation and metallurgical treatment of lead-silver deposits in Greece, have also resulted in significant abandoned sites, such as the one in Lavrion. Mining activities in Lavrio, were initiated in ancient times and continued until the 1980s, resulting in the production of significant waste stockpiles deposited in the area, crucial for the local water resources. Ιn many mining sites, environmental pressures are also recorded after the mine closure to the aquatic environment, as the surface waters flow through waste dump areas and contaminated soils. This paper aims to the geospatial visualization of the mining activities in Greece, in connection to their negative (surface- and/or ground-water pollution; overpumping due to extensive dewatering practices) or positive (enhanced groundwater recharge; pit lakes, improvement of water budget in the catchment scale) impacts on local water resources.

  9. Occurrence and fate of nitrification and urease inhibitors in the aquatic environment.

    Science.gov (United States)

    Scheurer, Marco; Brauch, Heinz-Jürgen; Schmidt, Carsten K; Sacher, Frank

    2016-08-10

    Nitrification and urease inhibitors (NUIs) decelerate the bacterial oxidation of nitrogen species by suppressing the activity of soil microorganisms. Thus, nitrogen losses can be limited and the efficiency of nitrogen fertilizers can be increased. After application NUI transfers to surface water may occur through leaching or surface run-off. In order to assess the occurrence of nitrification and urease inhibitors in the aquatic environment a multi-analyte high-performance liquid chromatography-mass spectrometry method was developed. 1H-1,2,4-Triazole and dicyandiamide (DCD) were detected for the first time in German surface waters. Only at a few sites 1H-1,2,4-triazole has been episodically detected with concentrations up to the μg L(-1)-range. DCD was ubiquitously present in German surface waters. An industrial site was identified as the point source of DCD being responsible for exceptionally high DCD concentrations of up to 7.2 mg L(-1) in close proximity to the point of discharge. Both compounds were also detected in at least one wastewater treatment plant effluent, but their concentrations in surface waters did not correlate with those of typical markers for domestic wastewater. Other NUIs were not detected in any of the samples. Laboratory-scale batch tests proved that 1H-1,2,4-triazole and DCD are not readily biodegradable, are not prone to hydrolysis and do not tend to adsorb onto soil particles. Ozonation and activated carbon filtration proved to be ineffective for their removal. PMID:27058057

  10. Occurrence and solid-liquid partition of sulfonated naphthalene-formaldehyde condensates in the aquatic environment.

    Science.gov (United States)

    Lange, Frank T; Merklinger, Michael; Wenz, Michael; Brauch, Heinz-J; Lehmann, Markus; Pinter, Istvan

    2005-03-15

    Sulfonated naphthalene-formaldehyde condensates (SNFC) are high production volume chemicals used in a variety of applications, for example, as concrete plasticizers, tanning agents, or dye dispersants. They enter the aquatic environment primarily by the wastewater path. The occurrence and fate of the monomers, which are different isomers of mono- and disulfonated naphthalene, was intensively investigated in previous studies. However, the environmental fate of the persistent higher molecular SNFC is so far widely unknown. This paper describes an ultrasonic extraction under alkaline conditions, followed by ion-pair HPLC with fluorescence detection for the analysis of SNFC oligomers from solid environmental matrixes such as sewage sludge, suspended solids, and river sediments. Limits of quantification of about 0.1 mg kg-1 d.m. were well below the measured concentrations in environmental samples. SNFC were adsorbed to suspended solids and river sediments in three major German rivers (Rhine, Neckar, and Danube) in concentrations typically up to several mg kg(-1) d.m. A total content of about 4 g kg(-1) d.m. was measured in a sewage sludge of a municipal wastewater treatment plant, which receives wastewater from a textile dyeing plant. Furthermore, the first quantitative field data on the partition of SNFC and their monomers between the aqueous phase and solid environmental compartments are presented. Solid-liquid partition coefficients (Kd) of oligomers with a chain-length ranging from three to six naphthalenesulfonate units were derived from the analysis of corresponding wastewater and sewage sludge samples and from suspended solids and river water samples, respectively. Determined Kd values were in the range from 10(2) to 10(4) L kg(-1). PMID:15819205

  11. Hazardous materials in aquatic environments of the Mississippi River Basin. Annual technical report, 30 December 1992--29 December 1993

    International Nuclear Information System (INIS)

    Tulane and Xavier Universities have singled out the environment as a major strategic focus for research and training for now and beyond the year 2000. In 1989, the Tulane/Xavier Center for Bioenvironmental Research (CBR) was established as the umbrella organization which coordinates environmental research at both universities. In December, 1992, the Tulane/Xavier DBR was awarded a five year grant to study pollution in the Mississippi River system. The ''Hazardous Materials in Aquatic Environments of the Mississippi River Basin'' project is a broad research and education program aimed at elucidating the nature and magnitude of toxic materials that contaminate aquatic environments of the Mississippi River Basin. Studies include defining the complex interactions that occur during the transport of contaminants, the actual and potential impact on ecological systems and health, and the mechanisms through which these impacts might be remediated. The Mississippi River Basin represents a model system for analyzing and solving contamination problems that are found in aquatic systems world-wide. Individual papers have been processed separately for inclusion in the appropriate data bases

  12. Hazardous materials in aquatic environments of the Mississippi River Basin. Annual technical report, 30 December 1992--29 December 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-31

    Tulane and Xavier Universities have singled out the environment as a major strategic focus for research and training for now and beyond the year 2000. In 1989, the Tulane/Xavier Center for Bioenvironmental Research (CBR) was established as the umbrella organization which coordinates environmental research at both universities. In December, 1992, the Tulane/Xavier DBR was awarded a five year grant to study pollution in the Mississippi River system. The ``Hazardous Materials in Aquatic Environments of the Mississippi River Basin`` project is a broad research and education program aimed at elucidating the nature and magnitude of toxic materials that contaminate aquatic environments of the Mississippi River Basin. Studies include defining the complex interactions that occur during the transport of contaminants, the actual and potential impact on ecological systems and health, and the mechanisms through which these impacts might be remediated. The Mississippi River Basin represents a model system for analyzing and solving contamination problems that are found in aquatic systems world-wide. Individual papers have been processed separately for inclusion in the appropriate data bases.

  13. Detection and identification of free-living amoeba from aquatic environment in different seasons in Taiwan

    Science.gov (United States)

    Tzeng, K.; Hsu, B.; Tsai, H.; Huang, P.; Tsai, J.; Kao, P.; Huang, K.; Chen, J.

    2013-12-01

    Free-living amoeba includes Acanthamoeba and Naegleria, which are widely distributed in water and soil. Human infection with free-living amoeba leads to serious illness, even lethal. For example, central nervous system infection will cause amoebic meningoencephalitis, and infections will cause amoebic keratitis. The presence of free-living amoeba in environment water can be used as a water quality indicator in ecosystem assessment. In Taiwan, reservoirs are indispensable because of the water source are limited by the steep terrain and the short river flow. Therefore, we need to pay more attention in the quality control of reservoirs water. The aims of this study are to investigate the presence of free-living amoeba in Taiwan reservoirs, and to compare the differences among seasons. At last, the identification and genotyping of Acanthamoeba and Naegleria are investigated. In this study, we use polymerase chain reaction with specific primers to analyze the presence of free-living amoeba in aquatic environment. We collected total 60 samples from reservoirs in Taiwan. The water samples are divided into two parts for both direct concentration method and culture method. The results show the different detection rates among seasons. For Acanthamoeba, the detection rates were 28.3% (17 of 60 water samples), 21.7% (13 of 60 water samples) and 8.3% (5 of 60 water samples) in autumn, winter and spring, respectively. For Naegleria, the detection rates were 6.7% (4 of 60 water samples), 0% (0 of 60 water samples) and 0% (0 of 60 water samples) were detected positive in autumn, winter and spring, respectively. Sequence analysis showed that the major genotypes in Acanthamoeba were T3, T4, T10 and T11 in autumn, T2, T4 and T10 in winter, T4 in spring. Due to the presences of Acanthamoeba and Naegleria in reservoirs, we should pay more attention in water quality monitoring to prevent the potential risks of diseases. Keywords: free-living amoeba, Acanthamoeba, Naegleria, polymerase

  14. Nonexercise activity thermogenesis (NEAT): environment and biology.

    Science.gov (United States)

    Levine, James A

    2004-05-01

    Nonexercise activity thermogenesis (NEAT) is the energy expended for everything that is not sleeping, eating, or sports-like exercise. It includes the energy expended walking to work, typing, performing yard work, undertaking agricultural tasks, and fidgeting. NEAT can be measured by one of two approaches. The first is to measure or estimate total NEAT. Here, total daily energy expenditure is measured, and from it "basal metabolic rate-plus-thermic effect of food" is subtracted. The second is the factoral approach, whereby the components of NEAT are quantified, and total NEAT is calculated by summing these components. The amount of NEAT that humans perform represents the product of the amount and types of physical activities and the thermogenic cost of each activity. The factors that impact a human's NEAT are readily divisible into environmental factors, such as occupation or dwelling within a "concrete jungle," and biological factors such as weight, gender, and body composition. The combined impact of these factors explains the substantial variance in human NEAT. The variability in NEAT might be viewed as random, but human and animal data contradict this. It appears that changes in NEAT subtly accompany experimentally induced changes in energy balance and are important in the physiology of weight change. Inadequate modulation of NEAT plus a sedentary lifestyle may thus be important in obesity. It then becomes intriguing to dissect mechanistic studies that delineate how NEAT is regulated into neural, peripheral, and humoral factors. A scheme is described in this review in which NEAT corresponds to a carefully regulated "tank" of physical activity that is crucial for weight control. PMID:15102614

  15. Detection of endocrine active substances in the aquatic environment in southern Taiwan using bioassays and LC-MS/MS.

    Science.gov (United States)

    Chen, Kuang-Yu; Chou, Pei-Hsin

    2016-06-01

    Endocrine active substances, including naturally occurring hormones and various synthetic chemicals have received much concern owing to their endocrine disrupting potencies. It is essential to monitor their environmental occurrence since these compounds may pose potential threats to biota and human health. In this study, yeast-based reporter assays were carried out to investigate the presence of (anti-)androgenic, (anti-)estrogenic, and (anti-)thyroid compounds in the aquatic environment in southern Taiwan. Liquid chromatography tandem mass spectrometry (LC-MS/MS) was also used to measure the environmental concentrations of selected endocrine active substances for assessing potential ecological risks and characterizing contributions to the endocrine disrupting activities. Bioassay results showed that anti-androgenic (ND-7489 μg L(-1) flutamide equivalent), estrogenic (ND-347 ng L(-1) 17β-estradiol equivalent), and anti-thyroid activities were detected in the dissolved and particulate phases of river water samples, while anti-estrogenic activities (ND-10 μg L(-1) 4-hydroxytamoxifen equivalent) were less often found. LC-MS/MS analysis revealed that anti-androgenic and estrogenic contaminants, such as bisphenol A, triclosan, and estrone were frequently detected in Taiwanese rivers. In addition, their risk quotient values were often higher than 1, suggesting that they may pose an ecological risk to the aquatic biota. Further identification of unknown anti-androgenic and estrogenic contaminants in Taiwanese rivers may be necessary to protect Taiwan's aquatic environment. PMID:26971174

  16. Fate of engineered cerium oxide nanoparticles in an aquatic environment and their toxicity toward 14 ciliated protist species.

    Science.gov (United States)

    Zhang, Wei; Pu, Zhichao; Du, Songyan; Chen, Yongsheng; Jiang, Lin

    2016-05-01

    The potential environmental impacts of engineered cerium oxide nanoparticles (CeO2 NPs) on aquatic organisms have remained largely unknown. Therefore, the laboratory study featured herein was performed to determine the fate of CeO2 NPs in an aquatic environment and their toxicity towards 14 different ciliated protist species at a specified population level. An investigation of 48 h aggregation kinetics in the Dryl's solution showed the CeO2 NPs to be relatively stable. The pH values in three test medium were too far away from PZC, which explained the stability of CeO2 NPs. CeO2 NPs generally elicited more toxicity with increasing NP concentration, following certain dose-response relationships. Nano-CeO2 resulted in greater toxicity in a particle state than when added as bulk material. LC50 values showed a negative correlation with the surface-to-volume ratio for these protists, suggesting that surface adsorption of CeO2 NPs might contribute to the observed toxicity. Additionally, acute toxic responses of 14 ciliated protist species to CeO2 NPs were not significantly phylogenetically conserved. The results of these observations provide a better insight into the potential risks of CeO2 NPs in an aquatic environment. PMID:26986089

  17. Influence of pH on the survival of Dictyosphaerium chlorelloides populations living in aquatic environments highly contaminated with chromium.

    Science.gov (United States)

    Pereira, María; Bartolomé, M Carmen; Sánchez-Fortún, Sebastián

    2013-12-01

    The accommodation of photosynthetic organisms to adverse conditions, such as pH changes in the aquatic environment, and their response to aquatic pollutants is essential to develop future biosensors. The present study reports the ability of both Cr(VI)-sensitive and tolerant Dyctiosphaerium chlorelloides strains to live in aqueous solutions highly contaminated with hexavalent chromium under varying ranges of pH, by the determination of chromium toxic effects on these strains. Studies of cell growth, photosynthetic quantum yield and gross photosynthesis rate show that both D. chlorelloides strains are able to survive in alkaline and moderately acidified (pH 4.25) aquatic environments. Below this pH value cell populations from both strains exposed for short periods of time to Cr(VI) showed alterations in the three parameters studied. There were no significant differences comparing the response of both strains at pH change in the culture medium. However, Cr(VI)-tolerant strain exhibits a better fit to maintain cell growth than Cr(VI)-sensitive strain when both were subjected to pH 4.25 in the culture medium. The absence of significant differences in photosynthetic activity results for both strains suggests that the lower sensitivity exhibited by Cr(VI)-tolerant strain would be due to cellular morphological changes rather than changes in cellular activity. PMID:24125866

  18. Environmental Parasitology. Interactions between parasites and pollutants in the aquatic environment

    Directory of Open Access Journals (Sweden)

    Sures B.

    2008-09-01

    Full Text Available In recent years there has been an increasing number of papers showing how parasitism and pollution can interact with each other in aquatic organisms. Among the variety of investigated aspects especially the combined effects of pollution and simultaneous infection on the health of aquatic hosts (molluscs, crustaceans, fish, mammals is of considerable interest. Effects of pollution on the occurrence and distribution of parasites is another interesting field of “Environmental Parasitology” attracting increasing attention. This mini-review presents some promising examples of interdisciplinary studies paying attention to the fact that under natural conditions no organism will only be affected by either parasites or pollution.

  19. Biodegradation and anticholinesrerase activity of methyl isocyanate in the aquatic environment of Bhopal

    Digital Repository Service at National Institute of Oceanography (India)

    SenGupta, R.; Sarkar, A.; Kureishy, T.W.

    at the aquatic fate of MIC and acetylcholinesterase (ACHE) inhibition in aquatic living beings. There are two lakes at Bhopal, one of them, the Upper Lake, is the source of water supply to the city and is quite some distance from the Union Carbide factory..., the source of pollution (Fig. 1). It is also the recipient of sewage from the city. The other lake, the Lower Lake, is very close to the factory, smaller in area and is completely eutrophic. The MIC-affected area of Bhopal is shown in Fig. 1. This report...

  20. Hazardous materials in Aquatic environments of the Mississippi River basin. Quarterly project status report, 1 January 1994--30 March 1994

    Energy Technology Data Exchange (ETDEWEB)

    Abdelghani, A.

    1994-06-01

    Projects associated with this grant for studying hazardous materials in aquatic environments of the Mississippi River Basin are reviewed and goals, progress and research results are discussed. New, one-year initiation projects are described briefly.

  1. Cosmet'eau-Changes in the personal care product consumption practices: from whistle-blowers to impacts on aquatic environments.

    Science.gov (United States)

    Bressy, Adèle; Carré, Catherine; Caupos, Émilie; de Gouvello, Bernard; Deroubaix, José-Frédéric; Deutsch, Jean-Claude; Mailler, Romain; Marconi, Anthony; Neveu, Pascale; Paulic, Laurent; Pichon, Sébastien; Rocher, Vincent; Severin, Irina; Soyer, Mathilde; Moilleron, Régis

    2016-07-01

    The Cosmet'eau project (2015-2018) investigates the "changes in the personal care product (PCP) consumption practices: from whistle-blowers to impacts on aquatic environments." In this project, the example of PCPs will be used to understand how public health concerns related to micropollutants can be addressed by public authorities-including local authorities, industries, and consumers. The project aims to characterize the possible changes in PCP consumption practices and to evaluate the impact of their implementation on aquatic contamination. Our goals are to study the whistle-blowers, the risk perception of consumers linked with their practices, and the contamination in parabens and their substitutes, triclosan, and triclocarban from wastewater to surface water. The project investigates the following potential solutions: modifications of industrial formulation or changes in consumption practices. The final purpose is to provide policy instruments for local authorities aiming at building effective strategies to fight against micropollutants in receiving waters. PMID:27179812

  2. Accumulation and discharge behavior of Cs-137 by zebra fish (Brachydanio rerio) in different aquatic environments

    International Nuclear Information System (INIS)

    The uptake and release kinetics of 137Cs from water by the tropical fish Brachydanio rerio was studied under controlled laboratory conditions. The accumulation of this radionuclide from food was avoided by feeding the fish separately in an inactive environment. A steep inverse dependence of bioconcentration factor (BCF) with potassium concentration was observed. This can formally be described by the Equation BCF=5.2 · [K+]-0.44. The elimination rate constant K in fresh water conditions was found to have a magnitude of 0.014±0.003 d-1 which corresponded to a biological half-life of 51±10 days. The uptake and release kinetics of Brachydanio rerio were compared with earlier studies of fresh water fishes. (author) 26 refs.; 2 figs.; 1 tab

  3. Micronuclei as biomarkers of genotoxicity of gamma radiation in aquatic environments

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Luanna R.S.; Silva, Edvane B.; Melo, Ana M.M.A. [Universidade Federal de Pernambuco (GERAR/DEN/UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia; Silva, Ronaldo C. da [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Genetica; Amancio, Francisco F. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia. Lab. de Radiobiologia

    2011-07-01

    Ionizing radiation is a genotoxic agent, inducing gene mutations and cellular death. Several efforts have been defendants in the development of techniques for measurement of radiation damage in biological systems. Among these techniques, micronuclei test has been showing as a great bio marker of DNA damage, being used in environmental monitoring to detect genotoxic agents in the environment. Additionally, organisms as Biomphalaria glabrata, freshwater molluscs, presents itself as an excellent model to assess damage caused by physical and chemical agents, due their biological and environmental characteristics. The snails were divided into groups of 5 individuals exposed to doses of 0 (control), 25, 35, 45 and 55 Gy of {sup 60}Co. After 48 hours of irradiation, the hemo lymph was collected and prepared the slides, which were stained with Giemsa and analyzed the cellular changes in haemocytes Statistical analysis was accomplished through chi-square test, ANOVA and Tukey test (p< 0,05). The results indicated that B. glabrata showed to be sensitive to gamma radiation. The snails irradiated with 35 Gy showed a decrease of haemocytes, while that of 55 Gy increased. Cellular and morphological changes were observed at doses of 35, 45 and 55 Gy and the dose of 55 Gy, the most radiotoxic. (author)

  4. Micronuclei as biomarkers of genotoxicity of gamma radiation in aquatic environments

    International Nuclear Information System (INIS)

    Ionizing radiation is a genotoxic agent, inducing gene mutations and cellular death. Several efforts have been defendants in the development of techniques for measurement of radiation damage in biological systems. Among these techniques, micronuclei test has been showing as a great bio marker of DNA damage, being used in environmental monitoring to detect genotoxic agents in the environment. Additionally, organisms as Biomphalaria glabrata, freshwater molluscs, presents itself as an excellent model to assess damage caused by physical and chemical agents, due their biological and environmental characteristics. The snails were divided into groups of 5 individuals exposed to doses of 0 (control), 25, 35, 45 and 55 Gy of 60Co. After 48 hours of irradiation, the hemo lymph was collected and prepared the slides, which were stained with Giemsa and analyzed the cellular changes in haemocytes Statistical analysis was accomplished through chi-square test, ANOVA and Tukey test (p< 0,05). The results indicated that B. glabrata showed to be sensitive to gamma radiation. The snails irradiated with 35 Gy showed a decrease of haemocytes, while that of 55 Gy increased. Cellular and morphological changes were observed at doses of 35, 45 and 55 Gy and the dose of 55 Gy, the most radiotoxic. (author)

  5. Management of contaminated aquatic environment with implementation of multi criteria decision analysis

    International Nuclear Information System (INIS)

    Problems of using the multi criteria analysis methods (MAM) to management of contaminated aquatic territories are considered. The MAM review is presented. Two practical problems of ranking the proposed measured for management of the contaminated bottom sediments are investigated with application of different MAM

  6. Biological diversity, ecological health and condition of aquatic assemblages at national wildlife refuges in southern indiana, USA.

    Science.gov (United States)

    Simon, Thomas P; Morris, Charles C; Robb, Joseph R; McCoy, William

    2015-01-01

    The National Wildlife Refuge system is a vital resource for the protection and conservation of biodiversity and biological integrity in the United States. Surveys were conducted to determine the spatial and temporal patterns of fish, macroinvertebrate, and crayfish populations in two watersheds that encompass three refuges in southern Indiana. The Patoka River National Wildlife Refuge had the highest number of aquatic species with 355 macroinvertebrate taxa, six crayfish species, and 82 fish species, while the Big Oaks National Wildlife Refuge had 163 macroinvertebrate taxa, seven crayfish species, and 37 fish species. The Muscatatuck National Wildlife Refuge had the lowest diversity of macroinvertebrates with 96 taxa and six crayfish species, while possessing the second highest fish species richness with 51 species. Habitat quality was highest in the Muscatatuck River drainage with increased amounts of forested habitats compared to the Patoka River drainage. Biological integrity of the three refuges ranked the Patoka NWR as the lowest biological integrity (mean IBI reach scores = 35 IBI points), while Big Oaks had the highest biological integrity (mean IBI reach score = 41 IBI points). The Muscatatuck NWR had a mean IBI reach score of 31 during June, which seasonally increased to a mean of 40 IBI points during summer. Watershed IBI scores and habitat condition were highest in the Big Oaks NWR. PMID:25632261

  7. Biological Diversity, Ecological Health and Condition of Aquatic Assemblages at National Wildlife Refuges in Southern Indiana, USA

    Directory of Open Access Journals (Sweden)

    Thomas Simon

    2015-01-01

    Full Text Available The National Wildlife Refuge system is a vital resource for the protection and conservation of biodiversity and biological integrity in the United States. Surveys were conducted to determine the spatial and temporal patterns of fish, macroinvertebrate, and crayfish populations in two watersheds that encompass three refuges in southern Indiana. The Patoka River National Wildlife Refuge had the highest number of aquatic species with 355 macroinvertebrate taxa, six crayfish species, and 82 fish species, while the Big Oaks National Wildlife Refuge had 163 macroinvertebrate taxa, seven crayfish species, and 37 fish species. The Muscatatuck National Wildlife Refuge had the lowest diversity of macroinvertebrates with 96 taxa and six crayfish species, while possessing the second highest fish species richness with 51 species. Habitat quality was highest in the Muscatatuck River drainage with increased amounts of forested habitats compared to the Patoka River drainage. Biological integrity of the three refuges ranked the Patoka NWR as the lowest biological integrity (mean IBI reach scores = 35 IBI points, while Big Oaks had the highest biological integrity (mean IBI reach score = 41 IBI points. The Muscatatuck NWR had a mean IBI reach score of 31 during June, which seasonally increased to a mean of 40 IBI points during summer. Watershed IBI scores and habitat condition were highest in the Big Oaks NWR.

  8. Spatial and temporal distribution of free-living protozoa in aquatic environments of a Brazilian semi-arid region

    Directory of Open Access Journals (Sweden)

    Maria Luisa Quinino de Medeiros

    2013-08-01

    Full Text Available Free-living protozoa organisms are distributed in aquatic environments and vary widely in both qualitative and quantitative terms. The unique ecological functions they exhibit in their habitats help to maintain the dynamic balance of these environments. Despite their wide range and abundance, studies on geographical distribution and ecology, when compared to other groups, are still scarce. This study aimed to identify and record the occurrence of free-living protozoa at three points in Piancó-Piranhas-Açu basin, in a semi-arid area of Rio Grande do Norte (RN state, and to relate the occurrence of taxa with variations in chlorophyll a, pH and temperature in the environments. Samples were collected in the Armando Ribeiro Gonçalves Dam, from two lentic environments upstream and a lotic ecosystem downstream. Sixty-five taxa of free-living protozoa were found. The Student's t-test showed significant inter-variable differences (p <0.05. Similar protozoan species were recorded under different degrees of trophic status according to chlorophyll a concentrations, suggesting the organisms identified are not ideal for indicating trophic level. We hypothesize that food availability, the influence of lentic and lotic systems and the presence of aquatic macrophytes influenced protozoan dynamics during the study period.

  9. Occurrence of xenobiotic ligands for retinoid X receptors and thyroid hormone receptors in the aquatic environment of Taiwan

    International Nuclear Information System (INIS)

    Highlights: • Xenobiotic RXR agonists and antagonists were found in river systems in Taiwan. • Potential TR antagonists were mainly detected in water extracts. • Samples collected near the river mouths exhibited high RXR disrupting activity. • RXR/TR antagonist activity in water became stronger after HPLC fractionation. • Bioassays are useful tools to investigate xenobiotic ligands for nuclear receptors. - Abstract: Various synthetic compounds are frequently discharged into the environment via human activities. Among them, certain contaminants may disrupt normal physiological functions of wildlife and humans via interactions with nuclear receptors. To protect human health and the environment, it is important to detect environmental ligands for human nuclear receptors. In this study, yeast-based reporter gene assays were used to investigate the occurrence of xenobiotic ligands for retinoid X receptors (RXR) and thyroid hormone receptors (TR) in the aquatic environment of Taiwan. Experimental results revealed that RXR agonist/antagonist activity was detected in river water and sediment samples. In particular, high RXR agonist/antagonist activity was found in the samples collected near river mouths. Additionally, few samples also elicited significant TR antagonist activity. Our findings show that the aquatic environment of Taiwan was contaminated with RXR and TR ligands. Further study is necessary to identify these xenobiotic RXR and TR agonists and antagonists

  10. Wildlife and biological resources: Chapter 5 in A synthesis of aquatic science for management of Lakes Mead and Mohave

    Science.gov (United States)

    Chandra, Sudeep; Abella, Scott R.; Albrecht, Brandon A.; Barnes, Joseph G.; Engel, E. Cayenne; Goodbred, Steven L.; Holden, Paul B.; Kegerries, Ron B.; Jaeger, Jef R.; Orsak, Erik; Rosen, Michael R.; Sjöberg, Jon; Wong, Wai Hing

    2012-01-01

    The creation of Lakes Mead and Mohave drastically changed habitats originally found along their region of the historical Colorado River. While still continuing to provide habitat conditions that support a rich diversity of species within the water, along shorelines, and in adjacent drainage areas, the reservoirs contain organisms that are both native and non-native to the Colorado River drainage (fig. 5-1). The diversity of species within these lakes continues to change with time due to changing habitat conditions, the invasion of non-native species, and extirpations of native species. From the bottom of the food web to the top predators, all organisms within the ecosystem are interconnected in food webs or food-chain networks. As non-native invasive species continue to be introduced into the lakes, alterations to the food web, species competition, and species predation likely will continue to change the ecosystem and populations of native organisms. Following an overview of the food web, this chapter summarizes information on aquatic and aquatic-dependent wildlife at Lakes Mead and Mohave and their relationships within the food web from members of lower trophic levels to the highest: phytoplankton, invertebrates, including zooplankton, and macroinvertebrates; fishes; and birds. The following sections describe the biological diversity, limiting factors, and ecological functions of these groups in Lake Mead, and to a lesser extent, in Lake Mohave.

  11. Fabrication of nano-mosquitocides using chitosan from crab shells: Impact on non-target organisms in the aquatic environment.

    Science.gov (United States)

    Murugan, Kadarkarai; Anitha, Jaganathan; Dinesh, Devakumar; Suresh, Udaiyan; Rajaganesh, Rajapandian; Chandramohan, Balamurugan; Subramaniam, Jayapal; Paulpandi, Manickam; Vadivalagan, Chitravel; Amuthavalli, Pandiyan; Wang, Lan; Hwang, Jiang-Shiou; Wei, Hui; Alsalhi, Mohamad Saleh; Devanesan, Sandhanasamy; Kumar, Suresh; Pugazhendy, Kannaiyan; Higuchi, Akon; Nicoletti, Marcello; Benelli, Giovanni

    2016-10-01

    Mosquitoes are arthropods of huge medical and veterinary relevance, since they vector pathogens and parasites of public health importance, including malaria, dengue and Zika virus. Currently, nanotechnology is considered a potential eco-friendly approach in mosquito control research. We proposed a novel method of biofabrication of silver nanoparticles (AgNP) using chitosan (Ch) from crab shells. Ch-AgNP nanocomposite was characterized by UV-vis spectroscopy, FTIR, SEM, EDX and XRD. Ch-AgNP were tested against larvae and pupae of the malaria vector Anopheles stephensi obtaining LC50 ranging from 3.18 ppm (I) to 6.54 ppm (pupae). The antibacterial properties of Ch-AgNP were proved against Bacillus subtilis, Klebsiella pneumoniae and Salmonella typhi, while no growth inhibition was reported in assays conducted on Proteus vulgaris. Concerning non-target effects, in standard laboratory considtions the predation efficiency of Danio rerio zebrafishes was 68.8% and 61.6% against I and II instar larvae of A. stephensi, respectively. In a Ch-AgNP-contaminated environment, fish predation was boosted to 89.5% and 77.3%, respectively. Quantitative analysis of antioxidant enzymes SOD, CAT and LPO from hepatopancreas of fresh water crabs Paratelphusa hydrodromous exposed for 16 days to a Ch-AgNP-contaminated aquatic environment were conducted. Notably, deleterious effects of Ch-AgNP contaminating aquatic enviroment on the non-target crab P. hydrodromous were observed, particularly when doses higher than 8-10ppm are tested. Overall, this research highlights the potential of Ch-AGNP for the development of newer control tools against young instar populations of malaria mosquitoes, also highlighting some risks concerned the employ of nanoparticles in aquatic environments. PMID:27344400

  12. An assessment of aquatic radiation pathways in Ireland, 2008 Environment Report RL 16/08

    International Nuclear Information System (INIS)

    This report provides an assessment of aquatic radiation exposure pathways in Ireland relating to anthropogenic radioactivity in the Irish Sea. It comprises the results of a habits survey undertaken on the north east coast of Ireland; a dose assessment using the habits survey data; 2007 monitoring data provided by the RPII; and recommendations for changes to the 2007 east coast of Ireland marine monitoring programme conducted by the RPII

  13. Protein Method for Investigating Mercuric Reductase Gene Expression in Aquatic Environments

    OpenAIRE

    Ogunseitan, O A

    1998-01-01

    A colorimetric assay for NADPH-dependent, mercuric ion-specific oxidoreductase activity was developed to facilitate the investigation of mercuric reductase gene expression in polluted aquatic ecosystems. Protein molecules extracted directly from unseeded freshwater and samples seeded with Pseudomonas aeruginosa PU21(Rip64) were quantitatively assayed for mercuric reductase activity in microtiter plates by stoichiometric coupling of mercuric ion reduction to a colorimetric redox chain through ...

  14. Predicting transfers of 137Cs in terrestrial and aquatic environments: a whole-ecosystem approach

    OpenAIRE

    Smith, Jim; Cross, M.; Wright, S M

    2002-01-01

    lt is well known that during the years after a nuclear accident the bioavailability and environmental mobility of radionuclides may change significantly, resulting in significant changes in contamination of foodstuffs and surface waters. Studies on 137Cs and, to a lesser extent, 90Sr, have quantified these changes in some ecosystems. However, variability in temporal changes of these radionuclides in aquatic and terrestrial systems is not yet well quantified. Estimation of such variability is ...

  15. Identifying the risk to the aquatic environment of endocrine disrupters derived from agriculture

    OpenAIRE

    Matthiessen, Peter; Arnold, David; Johnson, Andrew; Pepper, Tim; Pottinger, Tom G.; Pulman, Kim G. T.; Williams, Richard

    2005-01-01

    EXECUTIVE SUMMARY 1. The purpose of this project was to review possible inputs to UK headwater streams of steroid hormones originating from livestock, to investigate hormone contamination in some streams in which concentrations were expected to be maximal, and to draw conclusions about possible risks that these hormones may pose to aquatic organisms. 2. The review concluded that although livestock in the UK excretes more steroid sex hormones (oestradiol and testosterone) than the hu...

  16. Hazardous materials in aquatic environments of the Mississippi River Basin. Quarterly project status report, October 1, 1993--December 31, 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-31

    This quarterly project status report discusses research projects being conducted on hazardous materials in aquatic environments of the Mississippi River basin. We continued to seek improvement in our methods of communication and interactions to support the inter-disciplinary, inter-university collaborators within this program. In addition to the defined collaborative research teams, there is increasing interaction among investigators across projects. Planning for the second year of the project has included the development of our internal request for proposals, and refining the review process for selection of proposals for funding.

  17. Porto Tolle thermoelectric power station and aquatic environment of Po Delta (Italy): Synthesis of data

    International Nuclear Information System (INIS)

    The 2400 MW, oil-fueled power station of Porto Tolle (Italy) potentially affects riverine, lagoon and marine sectors of the Po Delta. A synthesis is provided of the data gathered by several research lines, which studied different aspects of the environment during the pre-operational and operational period. Comparisons are made between the two periods and between stations more or less influenced by cooling water discharge. When river water is used for cooling (the majority of cases), some effects on water quality characteristics and on plankton community abundances are evident in the immediate vicinity of the outlet. In the lagoon (Sacca del Canarin) and in the stretch of sea in front of it, effects directly connected with the thermal effluent could not be detected. The geomorphological evolution of the lagoon, however, was influenced by the hydraulic modification brought about by the cooling circuit. This resulted in an enhancement of the biological production of the lagoon. The sea area is not affected in a significant way, but concern is raised about the interaction of cooling discharge and the eutrophic load from the Po River

  18. Hazardous materials in aquatic environments of the Mississippi River Basin Project management. Technical quarterly progress report, April 1, 1996--June 30, 1996

    Energy Technology Data Exchange (ETDEWEB)

    McLachlan, J.; Ide, C.F.; O`Connor, S.

    1996-08-01

    This quarterly report summarizes accomplishments for the Project examining hazardous materials in aquatic environments of the Mississippi River Basin. Among the many research areas summarized are the following: assessment of mechanisms of metal-induced reproductive toxicity in aquatic species as a biomarker of exposure; hazardous wastes in aquatic environment;ecological sentinels of aquatic contamination in the lower Mississippi River System; remediation of selected contaminants; rapid on-site immunassay for heavy metal contamination; molecular mechanisms of developmental toxicity induced by retinoids and retinoid-like molecules; resuseable synthetic membranes for the removal of aromatic and halogenated organic pollutants from waste water; Effects of steroid receptor activation in neurendocrine cell of the mammalian hypothalamus; modeling and assessment of environmental quality of louisiana bayous and swamps; enhancement of environmental education. The report also contains a summary of publications resulting from this project and an appendix with analytical core protocals and target compounds and metals.

  19. Effect of co-existing kaolinite and goethite on the aggregation of graphene oxide in the aquatic environment.

    Science.gov (United States)

    Huang, Guanxing; Guo, Huiyuan; Zhao, Jian; Liu, Yonghong; Xing, Baoshan

    2016-10-01

    Broad applications of graphene oxide (GO) will result in the release of GO into aquatic environments, where clay minerals and metal (hydr)oxides are commonly present. Thereby the interactions between GO and a binary system containing clay minerals and metal (hydr)oxides can occur. We investigated the aggregation of GO with kaolinite and kaolinite-goethite associations (KGAs) in aquatic systems under different pHs, ionic strengths, and GO concentrations. GO suspension was unstable at low pHs, and the aggregation of GO occurred in the presence of KGA-4% and KGA-10% until pH 5 and 6, respectively. Kaolinite decreased the critical coagulation concentration (CCC) of GO at pH 5.5 from around 50 to 20 mM NaCl due to the reduced energy barrier. Heteroaggregation of GO with KGAs was extremely sensitive to ionic strength at pH 5.5, and the CCC of GO in the presence of KGA-10% increased from less than 1 mM NaCl to 5 mM NaCl with the increase of pH from 5.5 to 9. The heteroaggregation extent of GO with KGAs was enhanced firstly, then reduced with the increase of GO concentrations at pH 5.0, which is likely because KGA plates were more efficiently wrapped by large-size GO sheets with increasing GO concentrations. These findings are useful for understanding and predicting the fate of GO in the relatively complicated aquatic and soil environments where binary minerals co-exist. PMID:27379727

  20. The evolution of an annual life cycle in killifish: adaptation to ephemeral aquatic environments through embryonic diapause.

    Science.gov (United States)

    Furness, Andrew I

    2016-08-01

    An annual life cycle is characterized by growth, maturity, and reproduction condensed into a single, short season favourable to development, with production of embryos (seeds, cysts, or eggs) capable of surviving harsh conditions which juveniles or adults cannot tolerate. More typically associated with plants in desert environments, or temperate-zone insects exposed to freezing winters, the evolution of an annual life cycle in vertebrates is fairly novel. Killifish, small sexually dimorphic fishes in the Order Cyprinodontiformes, have adapted to seasonally ephemeral water bodies across much of Africa and South America through the independent evolution of an annual life history. These annual killifish produce hardy desiccation-resistant eggs that undergo diapause (developmental arrest) and remain buried in the soil for long periods when fish have perished due to the drying of their habitat. Killifish are found in aquatic habitats that span a continuum from permanent and stable to seasonal and variable, thus providing a useful system in which to piece together the evolutionary history of this life cycle using natural comparative variation. I first review adaptations for life in ephemeral aquatic environments in killifish, with particular emphasis on the evolution of embryonic diapause. I then bring together available evidence from a variety of approaches and provide a scenario for how this annual life cycle evolved. There are a number of features within Aplocheiloidei killifish including their inhabitation of marginal or edge aquatic habitat, their small size and rapid attainment of maturity, and egg properties that make them particularly well suited to the colonization of ephemeral waters. PMID:25969869

  1. Nanomaterials in the aquatic environment: A European Union-United States perspective on the status of ecotoxicity testing, research priorities, and challenges ahead.

    Science.gov (United States)

    Selck, Henriette; Handy, Richard D; Fernandes, Teresa F; Klaine, Stephen J; Petersen, Elijah J

    2016-05-01

    The European Union-United States Communities of Research were established in 2012 to provide a platform for scientists to develop a "shared repertoire of protocols and methods to overcome nanotechnology environmental health and safety (nanoEHS) research gaps and barriers" (www.us-eu.org/). Based on work within the Ecotoxicology Community of Research (2012-2015) the present Focus article provides an overview of the state of the art of nanomaterials (NMs) in the aquatic environment by addressing different research questions, with a focus on ecotoxicological test systems and the challenges faced when assessing NM hazards (e.g., uptake routes, bioaccumulation, toxicity, test protocols, and model organisms). The authors' recommendation is to place particular importance on studying the ecological effects of aged/weathered NMs, as-manufactured NMs, and NMs released from consumer products in addressing the following overarching research topics: 1) NM characterization and quantification in environmental and biological matrices; 2) NM transformation in the environment and consequences for bioavailability and toxicity; 3) alternative methods to assess exposure; 4) influence of exposure scenarios on bioavailability and toxicity; 5) development of more environmentally realistic bioassays; and 6) uptake, internal distribution, and depuration of NMs. Research addressing these key topics will reduce uncertainty in ecological risk assessment and support the sustainable development of nanotechnology. Environ Toxicol Chem 2016;35:1055-1067. © 2016 SETAC. PMID:27089437

  2. Is there a risk associated with the insect repellent DEET (N,N-diethyl-m-toluamide) commonly found in aquatic environments?

    Science.gov (United States)

    Costanzo, S.D.; Watkinson, A.J.; Murby, E.J.; Kolpin, D.W.; Sandstrom, M.W.

    2007-01-01

    DEET (N,N-diethyl-m-toluamide) is the active ingredient of most commercial insect repellents. This compound has commonly been detected in aquatic water samples from around the world indicating that DEET is both mobile and persistent, despite earlier assumptions that DEET was unlikely to enter aquatic ecosystems. DEET's registration category does not require an ecological risk assessment, thus information on the ecological toxicity of DEET is sparse. This paper reviews the presence of DEET in aqueous samples from around the world (e.g. drinking water, streams, open seawater, groundwater and treated effluent) with reported DEET concentrations ranging from 40–3000 ng L− 1. In addition, new DEET data collected from 36 sites in coastal waterways from eastern Australia (detections ranging from 8 to 1500 ng L− 1) are examined. A summary of new and existing toxicity data are discussed with an emphasis on preparing a preliminary risk assessment for DEET in the aquatic environment. Collated information on DEET in the aquatic environment suggests risk to aquatic biota at observed environmental concentrations is minimal. However, the information available was not sufficient to conduct a full risk assessment due to data deficiencies in source characterisation, transport mechanisms, fate, and ecotoxicity studies. These risks warrant further investigation due to the high frequency that this organic contaminant is detected in aquatic environments around the world.

  3. How can increased use of biological N2 fixation in agriculture benefit the environment?

    International Nuclear Information System (INIS)

    Asymbiotic, associative or symbiotic biological N2 fixation (BNF), is a free and renewable resource, which should constitute an integral part of sustainable agro-ecosystems. Yet there has been a rapid increase in use of fertiliser N and a parallel decline in the cultivation of leguminous plants and BNF, especially in the developed world. Fertilisers have boosted crop yields, but intensive agricultural systems have increasingly negative effects on the atmospheric and aquatic environments. BNF, either alone or in combination with fertilisers and animal manures, may prove to be a better solution to supply nitrogen to the cropping systems of the future. This review focuses on the potential benefit of BNF on the environment especially on soil acidification, rhizosphere processes and plant CO2 fixation. As fertiliser N has supplanted BNF in agriculture the re-substitution of BNF is considered. What is the consequence of fertiliser N production on energy use? The effect of fertiliser use on the release of the greenhouse gas CO2 is estimated at approximately 1 % of the global anthropogenic emission of CO2. The role of BNF on nitrogen cycling, ammonia volatilisation, N2O emission and NO3 leaching suggests that BNF is less likely than fertilisers to cause losses during pre-cropping and cropping. Sometimes however the post-harvest losses may be greater, due to the special qualities of legume residues. Nevertheless, legumes provide other 'ecological services' including improved soil structure, erosion protection and greater biological diversity. (author)

  4. Radioactivity in the aquatic environment. A review of UK research 1994-1997 and recommendations for future work

    International Nuclear Information System (INIS)

    The national Radioactivity Research and Environmental Monitoring Committee (RADREM) provides a forum for liaison on UK research and monitoring in the radioactive substances and radioactive waste management fields. The committee aims to ensure that there is no unnecessary overlap between, or significant omission from, the research programmes of the various parts of Government, the regulatory bodies or industry. This report has been produced by the Aquatic Environment Sub-Committee (AESC) of RADREM. AESC is responsible for providing RADREM with scientific advice in the field of research relating to radionuclides in the aquatic environment, for reporting on the progress of research in this field and on future research requirements. The objectives of this report are presented in Section 2, and the membership of AESC given in Section 3. This report describes a review of research undertaken in the field of radioactivity in aquatic systems over the last three years (Section 4). The review updates previous reviews, the most recent of which being in 1993 (AESC, 1994). Future research requirements have been identified by AESC, considering past work and work in progress, and are presented in Section 5. Specific research requirements are discussed in Section 5, whilst Section 6 summarises the main areas where future research is identified as a priority. These areas are as follows: the movement and uptake of 99Tc and 14C in aquatic systems and biota; geochemical processes; off-shore sediments; non-equilibrium systems; radiation exposure during civil engineering works; further work on movement of radionuclides in salt marshes; development and validation of models. The specific objectives of this report are as follows: 1. To provide a summary of research undertaken in this field over the last three years. 2. To identify future research requirements. 3. To attach priorities to the future research requirements. It should be noted that the purpose of the report is to identify areas

  5. Daphnia as a model organism in limnology and aquatic biology: some aspects of its reproduction and development

    Directory of Open Access Journals (Sweden)

    Adam Petrusek

    2011-08-01

    Full Text Available Invertebrates comprise the overwhelming majority of all animal species - around 95% of described species, not including substantial cryptic variation. As it is an extremely diverse and heterogeneous group, research on various invertebrate taxa often follows parallel trajectories, with little interaction among experts on different groups. To promote sharing of knowledge within as well as across taxa, the International Society of Invertebrate Reproduction and Development (ISIRD was established in 1975 in Calicut, India. Since that time, the ISIRD has organised international conferences at three-year intervals where various aspects of invertebrate biology are presented and discussed, naturally with the focus on reproduction and development. Traditionally, marine invertebrate groups have been well represented at all ISIRD congresses, but freshwater invertebrates have often been relatively overlooked at these meetings. The 12th ISIRD congress took place between August 16 and 20, 2010 in Prague, the Czech Republic. Several different Czech institutions collaborated on the organisation of this meeting. As aquatic invertebrate research has a long tradition in the country, we decided to include a section dedicated to popular model organisms in aquatic ecology and evolutionary biology, the "water fleas", cladocerans of the genus Daphnia. The section entitled "Daphnia and other cladocerans as model organisms" was open to any aspects of cladoceran biology directly or indirectly related to their reproduction or development. Unfortunately, the timing of the Prague congress completely overlapped the triennial congress of the International Society of Theoretical and Applied Limnology (SIL in Cape Town, South Africa. This large meeting in a very attractive setting attracted many cladocerologists from all over the world, including Europe. Therefore, the Daphnia section of the Prague ISIRD meeting remained moderate in size, attracting 13 contributions (eight talks

  6. Biological invasions in the aquatic ecosystems of Europe as a threat to biodiversity

    OpenAIRE

    Wołczuk, Katarzyna; Mięsikowski, Michał; Jarzynka, Karolina; Wilczyńska, Bogdana

    2011-01-01

    In recent years biological invasions have become a serious ecological and socio-economic problem for many countries. Invasions are promoted by anthropogenic activity which is broadly understood as well as the instability of ecosystems. It carries a number of threats, often difficult to predict. The effects of invasion are long-term and occur on many levels of life. They can very often contribute to the extinction of native species, thus reducing biodiversity. According to the concept of susta...

  7. Theoretical training bases for young athletes in aquatic sports on the natural environment: Bodyboard.

    Directory of Open Access Journals (Sweden)

    Marcos Mecías Calvo

    2015-09-01

    Full Text Available The bodyboard is a surfing discipline whose growth has been considerably since the 60s, so it is considered one of the fastest growing aquatic sport in the world. Despite this, scientific research of this discipline has been reflected poorly compared to other sports. As in any other sport, the bodyboarder requires of specific physical and physiological conditions to help it to practice the sport effectively as it does not follow a specific training or develop conditioning programs. Therefore, this article comes up with the idea of providing a basis for determining the most appropriate training based on study objectives and bodyboard actions to improve physical, technical and psychological condition of the bodyboarders based on the particularities of their own sport and the athlete, taking into account scientific studies in the field at hand: the Bodyboard.

  8. Synthetic Self-Assembled Materials in Biological Environments.

    Science.gov (United States)

    Versluis, Frank; van Esch, Jan H; Eelkema, Rienk

    2016-06-01

    Synthetic self-assembly has long been recognized as an excellent approach for the formation of ordered structures on the nanoscale. Although the development of synthetic self-assembling materials has often been inspired by principles observed in nature (e.g., the assembly of lipids, DNA, proteins), until recently the self-assembly of synthetic molecules has mainly been investigated ex vivo. The past few years however, have witnessed the emergence of a research field in which synthetic, self-assembling systems are used that are capable of operating as bioactive materials in biological environments. Here, this up-and-coming field, which has the potential of becoming a key area in chemical biology and medicine, is reviewed. Two main categories of applications of self-assembly in biological environments are identified and discussed, namely therapeutic and imaging agents. Within these categories key concepts, such as triggers and molecular constraints for in vitro/in vivo self-assembly and the mode of interaction between the assemblies and the biological materials will be discussed. PMID:27042774

  9. [Escherichia coli: diversity of biochemical phenotypes in aquatic environments (Santa, Fe, Argentina)].

    Science.gov (United States)

    Emiliani, F; Lajmanovich, R; González, S M

    2001-01-01

    During certain environmental conditions, the floating aquatic vegetation, mainly represented by Eichhornia crassipes (water hyacinth) invade and even cover water courses assigned to recreational activities or to the supply of drinkable water. The rhizosphere of these plants constitutes an unknown biotope of bacteria of sanitary interest, possibly different from waters without vegetation and of the sediment of the same aquatic system. To verify such possibility, 206 isolated strains in MacConkey Agar (Difco) were typified and identified (78 from water, 65 from sediment and 63 from rhizosphere) using the API 20 E system (v. 4.0) and Apilab plus software (v 3.3.3), both of bioMérieux (Marcy-l'Etoile, France, 1998). Nineteen different biochemical phenotypes from E. coli were found. The 79% of the population belonged to only 7 phenotypes; the 21% remaining, to the other 12 phenotypes. Twelve phenotypes did not share the biotopes, while only 4 were in the three. These results (and those obtained by other authors who used the API 20 E system in other biotopes) suggest that it would be possible to characterize the rhizosphere using those phenotypes that are found in smaller proportion. The greatest index of diversity (H) and evenness (E) were found in the rhizosphere (H = 2.903; E = 0.874). The dendrogram (average distances and UPGMA method) reaffirms the dissimilarity in biochemical phenotypes of E. coli populations of the rhizosphere with regard to the other biotopes. The most abundant bacterial species in the three biotopes were E. coli, Klebsiella terrigena and K. pneumoniae, corresponding to 75.2% of the community. The rhizosphere differed from Serratia odorifera and from Klebsiella spp. because of its higher rate of isolation. PMID:11494758

  10. From municipal sewage to drinking water: fate and removal of pharmaceutical residues in the aquatic environment in urban areas.

    Science.gov (United States)

    Heberer, Th; Reddersen, K; Mechlinski, A

    2002-01-01

    Recently, the occurrence and fate of pharmaceutically active compounds (PhACs) in the aquatic environment was recognized as one of the emerging issues in environmental chemistry and as a matter of public concern. Residues of PhACs have been found as contaminants in sewage, surface, and ground- and drinking water samples. Since June 2000, a new long-term monitoring program of sewage, surface, ground- and drinking water has been carried out in Berlin, Germany. Samples, collected periodically from selected sites in the Berlin area, are investigated for residues of PhACs and related contaminants. The purpose of this monitoring is to investigate these compounds over a long time period to get more reliable data on their occurrence and fate in the different aquatic compartments. Moreover, the surface water investigations allow the calculation of season-dependent contaminant loads in the Berlin waters. In the course of the monitoring program, PhACs and some other polar compounds were detected at concentrations up to the microg/L-level in all compartments of the Berlin water cycle. The monitoring is accompanied and supported by several other investigations such as laboratory column experiments and studies on bank filtration and drinking water treatment using conventional or membrane filtration techniques. PMID:12227607

  11. The bioconcentration and bioaccumulation factors for molybdenum in the aquatic environment from natural environmental concentrations up to the toxicity boundary

    International Nuclear Information System (INIS)

    In a regulatory context, bioaccumulation or bioconcentration factors are used for considering secondary poisoning potential and assessing risks to human health via the food chain. In this paper, literature data on the bioaccumulation of molybdenum in the aquatic organisms are reviewed and assessed for relevance and reliability. The data available in the literature were generated at exposure concentrations below those recommended in the REACH registration dossiers for molybdenum compounds i.e. PNECfreshwater 12.7 mg Mo/L. To address possible environmental concerns at regulatorily-relevant molybdenum concentrations, both a field study and a laboratory study were conducted. In the field study, whole body and organ-specific molybdenum levels were evaluated in fish (eel, stickleback, perch, carp bream, roach) held in the discharge water collector tanks of a molybdenum processing plant, containing a mean measured molybdenum level of 1.03 mg Mo/L. In the laboratory study, rainbow trout were exposed to two different nominal molybdenum levels (1.0 and 12.7 mg Mo/L), for 60 days followed by a 60-day depuration period. Whole body concentrations in rainbow trout during the exposure period were between < 0.20 and 0.53 mg Mo/L. Muscle tissue molybdenum concentrations in fish taken from both experiments remained below 0.2 mg/kg dry wt. These studies show an inverse relationship between exposure concentration and bioconcentration or bioaccumulation factor for molybdenum. In aquatic organisms, and in fish in particular, internal molybdenum concentrations are maintained in the presence of variation in external molybdenum concentrations. These observations must be considered when evaluating potential risks associated with the bioconcentration and/or bioaccumulation of molybdenum in the aquatic environment. -- Highlights: ► Addressing environmental concerns at regulatory-relevant molybdenum concentrations. ► Inverse relationship between exposure levels and BAF (BAF increases as Mo

  12. Toxicity of certain heavy metals on fish in the aquatic environment

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — On the earth's crust there are 59 heavy metals of which 17 are considered toxic to biological communities. Here in Alaska, we have thus far considered the following...

  13. Functional Genomics and Cell Biology of the Dolphin (Tursiops runcatus): Establishment of Novel Molecular Tools to Study Marine Mammals in Changing Environments

    OpenAIRE

    Mancia, Annalaura

    2010-01-01

    The dolphin (Tursiops truncatus) is a mammal that is adapted to life in a totally aquatic environment. Despite the popularity and even iconic status of the dolphin, our knowledge of its physiology, its unique adaptations and the effects on it of environmental stressors are limited. One approach to improve this limited understanding is the implementation of established cellular and molecular methods to provide sensitive and insightful information for dolphin biology. We initiated our studi...

  14. Evaluation of the potential of Pistia stratiotes L. (water lettuce) for bioindication and phytoremediation of aquatic environments contaminated with arsenic.

    Science.gov (United States)

    Farnese, F S; Oliveira, J A; Lima, F S; Leão, G A; Gusman, G S; Silva, L C

    2014-08-01

    Specimens of Pistia stratiotes were subjected to five concentrations of arsenic (As) for seven days. Growth, As absorption, malondialdehyde (MDA) content, photosynthetic pigments, enzymatic activities, amino acids content and anatomical changes were assessed. Plant arsenic accumulation increased with increasing metalloid in the solution, while growth rate and photosynthetic pigment content decreased. The MDA content increased, indicating oxidative stress. Enzymatic activity and amino acids content increased at the lower doses of As, subsequently declining in the higher concentrations. Chlorosis and necrosis were observed in the leaves. Leaves showed starch accumulation and increased thickness of the mesophyll. In the root system, there was a loss and darkening of roots. Cell layers formed at the insertion points on the root stems may have been responsible for the loss of roots. These results indicate that water lettuce shows potential for bioindication and phytoremediation of As-contaminated aquatic environments. PMID:25627371

  15. Detection and size measurement of individual hemozoin nanocrystals in aquatic environment using a whispering gallery mode resonator

    CERN Document Server

    Kim, Woosung; Zhu, Jiangang; Faraz, Monifi; Coban, Cevayir; Yang, Lan; 10.1364/OE.20.029426

    2013-01-01

    We, for the first time, report the detection and the size measurement of single nanoparticles (i.e. polystyrene) in aquatic environment using mode splitting in a whispering gallery mode (WGM) optical resonator, namely a microtoroid resonator. Using this method we achieved detecting and measuring individual synthetic hemozoin nanocrystals, which are a hemoglobin degradation by-product of malarial parasites, dispersed in a solution or in air. The results of size measurement in solution and in air agree with each other and with those obtained using scanning electron microscope and dynamic light scattering. Moreover, we compare the sensing capabilities of the degenerate (single resonance) and non-degenerate (split mode, doublet) operation regimes of the WGM resonator.

  16. Chernobyl radionuclides in the environment: Tracers for the tight coupling of atmospheric, terrestrial, and aquatic geochemical processes

    International Nuclear Information System (INIS)

    Observations of the temporal trend in concentrations of Chernobyl radionuclides in atmospheric, terrestrial, and aquatic reservoirs near Duebendorf (Zurich) aided in quantifying fluxes and transfer velocities from one reservoir to another. Radionuclide dry and wet deposition rates and velocities from the atmosphere, washout from the catchment basins into surface waters, and deposition rates and mechanisms in lakes were determined. The results from these studies were compared to those from earlier observations on the fate of the radionuclides released by bomb tests, from reactor accidents, and from the purposeful tracer experiments in lakes. The results from our observations indicate the extent to which the Chernobyl radionuclides trace the movement of other atmospheric trace contaminants in the environment

  17. Triclosan as a surrogate for household biocides: an investigation into biocides in aquatic environments of a highly urbanized region.

    Science.gov (United States)

    Chen, Zhi-Feng; Ying, Guang-Guo; Liu, You-Sheng; Zhang, Qian-Qian; Zhao, Jian-Liang; Liu, Shuang-Shuang; Chen, Jun; Peng, Feng-Jiao; Lai, Hua-Jie; Pan, Chang-Gui

    2014-07-01

    Biocides are widely formulated in household and personal care products. We investigated the distribution and ecological risks of 16 household biocides in aquatic environments of a highly urbanized region in South China, evaluated triclosan as a chemical indicator for this group of household chemicals, and proposed a novel approach to predict the environmental occurrence and fate of these household biocides by using triclosan usage data and a level-III fugacity model. Eleven biocides were quantitatively detected at concentrations up to 264 ± 15.3 ng/L for climbazole in surface water, and up to 5649 ± 748 ng/g for triclocarban in sediment of four rivers in the region. The distribution of biocides in the aquatic environments was significantly correlated with environmental variables such as total nitrogen, total phosphorus and population. Domestic sewage in the region was the dominant pollution source for most biocides such as azole fungicides (fluconazole, climbazole, clotrimazole, ketoconazole, miconazole, and carbendazim) and disinfectants (triclosan and triclocarban). Preliminary risk assessment showed high ecological risks posed by two biocides carbendazim and triclosan in river waters. Mostly important, triclosan was found to be a reliable chemical indicator to surrogate household biocides both in water and sediment based on the correlation analysis. In addition, the fugacity modeling could provide simulated concentrations comparable to the monitoring results. Therefore, with the usage data of the chemical indicator triclosan and correlation formula with other biocides, this model can be applied for predicting the occurrence and fate of various household biocides in a catchment. PMID:24793342

  18. Preliminary studies of quality assessment of aquatic environments from Cluj suburban areas, based on some invertebrates bioindicators and chemical indicators

    Directory of Open Access Journals (Sweden)

    Gheorghe Stan

    2010-02-01

    Full Text Available Systematic categories of invertebrates bioindicators correlated with some chemical parameters,were an effective way to characterize the quality of lotic (Someş River and lentic (Lake Gilău aquatic environment from Cluj-Napoca area. Invertebrate fauna was represented by species belonging to the following dominant systematic categories: Nematoda, Annelida, Crustacea and Insecta. This paper containsalso some preliminary data on the bioindicators species belonging to Protozoa phylum. Dominant groups were crustaceans (the sampling points in Lake Gilău and annelids (Somes River and among species Gammarus pulex, Daphnia pulex, Tubifex tubifex. The fauna composition shows the β-α mesosaprobic character of the water, with an evolution from β mesosaprobity upstream the Cluj-Napoca city to polysaprobic downstream of the city. This aspect has been observed and analyzed according to chemical parameters (pH, TDS, ORP, EC, t and indices of saprobity (relative cleanliness, state of relative pollution, the deficit of species, saprobiological index.Systematic categories of invertebrates bioindicators correlated with some chemical parameters, were an effective way to characterize the quality of lotic (Someş River and lentic (Lake Gilău aquatic environment from Cluj-Napoca area. Invertebrate fauna was represented by species belonging to the following dominant systematic categories: Nematoda, Annelida, Crustacea and Insecta. This paper contains also some preliminary data on the bioindicators species belonging to Protozoa phylum. Dominant groups were crustaceans (the sampling points in Lake Gilău and annelids (Somes River and among species Gammarus pulex, Daphnia pulex, Tubifex tubifex. The fauna composition shows the β-α mesosaprobic character of the water, with an evolution from β mesosaprobity upstream the Cluj-Napoca city to polysaprobic downstream of the city. This aspect has been observed and analyzed according to chemical parameters (pH, TDS, ORP

  19. A Review on the Toxicity and Non-Target Effects of Macrocyclic Lactones in Terrestrial and Aquatic Environments

    Science.gov (United States)

    Lumaret, Jean-Pierre; Errouissi, Faiek; Floate, Kevin; Römbke, Jörg; Wardhaugh, Keith

    2012-01-01

    The avermectins, milbemycins and spinosyns are collectively referred to as macrocyclic lactones (MLs) which comprise several classes of chemicals derived from cultures of soil micro-organisms. These compounds are extensively and increasingly used in veterinary medicine and agriculture. Due to their potential effects on non-target organisms, large amounts of information on their impact in the environment has been compiled in recent years, mainly caused by legal requirements related to their marketing authorization or registration. The main objective of this paper is to critically review the present knowledge about the acute and chronic ecotoxicological effects of MLs on organisms, mainly invertebrates, in the terrestrial and aquatic environment. Detailed information is presented on the mode-of-action as well as the ecotoxicity of the most important compounds representing the three groups of MLs. This information, based on more than 360 references, is mainly provided in nine tables, presenting the effects of abamectin, ivermectin, eprinomectin, doramectin, emamectin, moxidectin, and spinosad on individual species of terrestrial and aquatic invertebrates as well as plants and algae. Since dung dwelling organisms are particularly important non-targets, as they are exposed via dung from treated animals over their whole life-cycle, the information on the effects of MLs on dung communities is compiled in an additional table. The results of this review clearly demonstrate that regarding environmental impacts many macrocyclic lactones are substances of high concern particularly with larval instars of invertebrates. Recent studies have also shown that susceptibility varies with life cycle stage and impacts can be mitigated by using MLs when these stages are not present. However information on the environmental impact of the MLs is scattered across a wide range of specialised scientific journals with research focusing mainly on ivermectin and to a lesser extent on abamectin

  20. Toxic effects of crude-oil-contaminated soil in aquatic environment on Carassius auratus and their hepatic antioxidant defense system

    Institute of Scientific and Technical Information of China (English)

    WANG Yuanyuan; ZHOU Qixing; PENG Shengwei; MA Lena Q; NIU Xiaowei

    2009-01-01

    Under the indoor simulant conditions, toxic effects of crude-oil-contaminated soil which was put into aquatic environment on the young fishes Carassius auratus and their hepatic antioxidant system after a 20-d exposure were investigated. Results showed that the relationship between the mortality of C. auratus and the exposed doses could be divided to 3 phases: fishes exposed to the low dose groups (0.5--5.0 g/L) were dead due to the ingestion of crude-oil-contaminated soils in aquatic environment; at the medium dose groups (5.0--25.0 g/L) fishes were dead due to the penetration of toxic substances; at the high dose groups (25.0--50.0 g/L) fishes were dead due to environmental stress. The highest mortality and death speed were found in the 1.0 g/L dose group, and the death speed was sharply increased in the 50.0 g/L dose group in the late phase of the exposure. The activity of superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) and the content of malaondialdehyde (MDA) in the hepatic tissues of C. auratus were induced significantly. The activity of SOD was first increased and then decreased, and was significantly inhibited in the 50.0 g/L dose group. The activity of CAT was highly induced, and restored to a little more than the control level when the exposed doses exceeded 10.0 g/L. The activity of GST was the most sensitive, it was significantly induced in all dose groups, and the highest elevation was up to 6 times in the 0.5 g/L dose group compared with the control. The MDA content was significantly elevated in the 50.0 g/L dose group, and the changes of the MDA content were opposite with the changes of the GST activity.

  1. Determination and occurrence of secondary alkane sulfonates (SAS) in aquatic environments.

    Science.gov (United States)

    Baena-Nogueras, Rosa María; González-Mazo, Eduardo; Lara-Martín, Pablo A

    2013-05-01

    A new methodology has been developed for the determination of secondary alkane sulfonates (SAS), an anionic surfactant, in environmental matrices. Sediment and sludge samples were extracted using pressurized liquid extraction and sonication, whereas wastewater and surface water samples were processed using solid-phase extraction. Extraction recoveries were acceptable for both aqueous (78-120%) and solid samples (83-100%). Determination of SAS was carried out by high or ultra performance liquid chromatography - mass spectrometry using ion trap and time-of-flight detectors. The methodology was applied to samples from Guadalete River (SW Spain), where SAS concentrations below 1 μg L(-1) were measured in surface water, and from 72 to 9737 μg kg(-1) in sediments. Differential partitioning was observed for SAS homologues as those having a longer hydrocarbon chain which preferentially sorbed onto particulate matter. A preliminary environmental risk assessment also showed that SAS measured levels were not harmful to the aquatic community in the sampling area. PMID:23421983

  2. Impacts of emerging contaminants on surrounding aquatic environment from a youth festival.

    Science.gov (United States)

    Jiang, Jheng-Jie; Lee, Chon-Lin; Fang, Meng-Der; Tu, Bo-Wen; Liang, Yu-Jen

    2015-01-20

    The youth festival as we refer to Spring Scream, a large-scale pop music festival, is notorious for the problems of drug abuse and addiction. The origin, temporal magnitudes, potential risks and mass inputs of emerging contaminants (ECs) were investigated. Thirty targeted ECs were analyzed by solid-phase extraction and liquid chromatography coupled to tandem mass spectrometry (SPE-LC-MS/MS). Sampling strategy was designed to characterize EC behavior in different stages (before and after the youth festival), based on multivariate data analysis to explore the contributions of contaminants from normal condition to the youth festival. Wastewater influents and effluents were collected during the youth festival (approximately 600 000 pop music fans and youth participated). Surrounding river waters are also sampled to illustrate the touristic impacts during peak season and off-season. Seasonal variations were observed, with the highest concentrations in April (Spring Scream) and the lowest in October (off-season). Acetaminophen, diclofenac, codeine, ampicillin, tetracycline, erythromycin-H2O, and gemfibrozil have significant pollution risk quotients (RQs > 1), indicating ecotoxicological concerns. Principal component analysis (PCA) and weekly patterns provide a perspective in assessing the touristic impacts and address the dramatic changes in visitor population and drug consumption. The highest mass loads discharged into the aquatic ecosystem corresponded to illicit drugs/controlled substances such as ketamine and MDMA, indicating the high consumption of ecstasy during Spring Scream. PMID:25495157

  3. [Mechanisms of Cr (VI) toxicity to fish in aquatic environment: A review].

    Science.gov (United States)

    Chen, Hong-xing; Wu, Xing; Bi, Ran; Li, Li-xia; Gao, Mi; Li, Dan; Xie, Ling-tian

    2015-10-01

    With increasing consumption and applications of chromium in metallurgy, electroplating, tanning process and stainless steel industry, chromium contamination has become a global environmental problem. In general, Cr(VI) has higher permeability across the cell membrane than Cr(III) and hence is considered more toxic than Cr(III). Oxidative stress could be induced following reactive oxygen species (ROS) normally produced in fish under Cr(VI) exposure due to its variable valences. Furthermore, the intermediates of Cr, e.g. Cr(V) and Cr(IV) , produced by cellular reduction processes can bind with DNA and result in mutagenic effects. These combined effects will threaten the growth, development and population structure of different fish species. In this paper, we reviewed published results on the toxic effects of Cr(VI) in fish at levels of molecules, tissues, organs and individuals. The mechanisms of toxicity and detoxification of Cr(VI) in various aspects were discussed. In addition, we also put forward perspectives on the toxicity of chromium in aquatic organisms. PMID:26995935

  4. Persistence and bioavaiability of manufactured silver nanoparticles in the aquatic environment

    DEFF Research Database (Denmark)

    Dai, Lina; Banta, Gary Thomas; Selck, Henriette;

    2011-01-01

    information is available in dissolution of MNPs in a complex environment, such as sediment, which is believed to be the final sink for released MNPs. We tested the dissolution of PVP-coated silver nanoparticles (AgNPs) and compared the ion diffusive kinetics with Ag(I) in 3 different media (MilliQ water......The environmental behavior of manufactured nanoparticles (MNPs) has received increasing attention. One of the focuses is whether they exist as particles or as dissolved ions in the environment. The dissolution of MNPs is a key to understand their behaviors in the environment. However, little...

  5. Using Stable Isotopes of Carbon and Nitrogen to Evaluate Trophic Interactions in Aquatic Environments

    Science.gov (United States)

    Christensen, David R.; LaRoche, Andrew

    2012-01-01

    This paper describes a series of laboratory exercises for upper level biology courses, independent research and/or honors programs. Students sampled fish from a local water body with the assistance of a local fish and wildlife agency. Tissue samples from collected fish were utilized to obtain estimates of the stable isotopes delta[superscript 13]C…

  6. A Simple Model of Tetracycline Antibiotic Resistance in the Aquatic Environment (with Application to the Poudre River

    Directory of Open Access Journals (Sweden)

    Sarah Sanchez

    2011-02-01

    Full Text Available Antibiotic resistance is a major concern, yet it is unclear what causes the relatively high densities of resistant bacteria in the anthropogenically impacted environment. There are various possible scenarios (hypotheses: (A Input of resistant bacteria from wastewater and agricultural sources is significant, but they do not grow in the environment; (B Input of resistant bacteria is negligible, but the resistant bacteria (exogenous or endogenous grow due to the selection pressure of the antibiotic; (C Exogenous bacteria transfer the resistance to the endogenous bacteria and those grow. This paper presents a simple mechanistic model of tetracycline resistance in the aquatic environment. It includes state variables for tetracyclines, susceptible and resistant bacteria, and particulate and dissolved organic matter in the water column and sediment bed. The antibiotic partitions between freely dissolved, dissolved organic matter (DOM-bound and solids-bound phases, and decays. Bacteria growth is limited by DOM, inhibited by the antibiotic (susceptible bacteria only and lower due to the metabolic cost of carrying the resistance (resistant bacteria only. Resistant bacteria can transfer resistance to the susceptible bacteria (conjugation and lose the resistance (segregation. The model is applied to the Poudre River and can reproduce the major observed (literature data patterns of antibiotic concentration and resistance. The model suggests observed densities of resistant bacteria in the sediment bed cannot be explained by input (scenario A, but require growth (scenarios B or C.

  7. Analysis, occurrence, fate and risks of proton pump inhibitors, their metabolites and transformation products in aquatic environment: A review.

    Science.gov (United States)

    Kosma, Christina I; Lambropoulou, Dimitra A; Albanis, Triantafyllos A

    2016-11-01

    Proton pump inhibitors (PPIs) which include omeprazole, esomeprazole, lansoprazole, pantoprazole and rabeprazole, are extensively used for the relief of gastro-intestinal disorders. Despite their high worldwide consumption, PPIs are extensively metabolized in human bodies and therefore are not regularly detected in monitoring studies. Very recently, however, it has been shown that some omeprazole metabolites may enter and are likely to persist in aquatic environment. Hence, to fully assess the environmental exposures and risks associated with PPIs, it is important to better understand and evaluate the fate and behavior not only of the parent compound but also of their metabolites and their transformation products arising from biotic and abiotic processes (hydrolysis, photodegradation, biodegradation etc.) in the environment. In this light, the purpose of this review is to summarize the present state of knowledge on the introduction and behavior of these chemicals in natural and engineering systems and highlight research needs and gaps. It draws attention to their transformation, the increase contamination by their metabolites/TPs in different environmental matrices and their potential adverse effects in the environment. Furthermore, existing research on analytical developments with respect to sample treatment, separation and detection of PPIs and their metabolites/TPs is provided. PMID:27380396

  8. Biodegradation and toxicity of vegetable oils in contaminated aquatic environments: Effect of antioxidants and oil composition.

    Science.gov (United States)

    Salam, Darine A; Suidan, Makram T; Venosa, Albert D

    2016-03-15

    Antioxidants may affect the oxidative rate of vegetable oils determining their fate and impact in contaminated aquatic media. In previous studies, we demonstrated the effectiveness of butylated hydroxytoluene (BHT), one of the most used antioxidants in edible oils, in enhancing the biodegradation of glyceryl trilinoleate, a pure triacylglycerol of cis,cis-9,12-octadecadienoic acid (C18:2 delta), through retarding its oxidative polymerization relatively to the oil with no added antioxidant. In this study, the effect of BHT on the biodegradation and toxicity of purified canola oil, a mixed-acid triacylglycerol with high C18:1 content, was investigated in respirometric microcosms and by use of the Microtox® assay. Investigations were carried out in the absence and presence (200 mg kg(-1)) of the antioxidant, and at an oil loading of 0.31 L m(-2) (333 gal acre(-1)). Substantial oil mineralization was achieved after 16 weeks of incubation (>77%) and was not significantly different (p>0.05) between the two BHT treatments, demonstrating an important role of the oil fatty acid composition in determining the potency of antioxidants and, consequently, the fate of spilled vegetable oils. Furthermore, for both treatments, toxicity was measured at early stages of the experiments and disappeared at a later stage of incubation. The observed transient toxicity was associated with the combined effect of toxic biodegradation intermediates and autoxidation products. These results were supported by the gradual disappearance of BHT in the microcosms initially supplemented with the antioxidant, reaching negligible amounts after only 2 weeks of incubation. PMID:26780134

  9. A tiered, integrated biological and chemical monitoring framework for contaminants of emerging concern in aquatic ecosystems.

    Science.gov (United States)

    Maruya, Keith A; Dodder, Nathan G; Mehinto, Alvine C; Denslow, Nancy D; Schlenk, Daniel; Snyder, Shane A; Weisberg, Stephen B

    2016-07-01

    The chemical-specific risk-based paradigm that informs monitoring and assessment of environmental contaminants does not apply well to the many thousands of new chemicals that are being introduced into ambient receiving waters. We propose a tiered framework that incorporates bioanalytical screening tools and diagnostic nontargeted chemical analysis to more effectively monitor for contaminants of emerging concern (CECs). The framework is based on a comprehensive battery of in vitro bioassays to first screen for a broad spectrum of CECs and nontargeted analytical methods to identify bioactive contaminants missed by the currently favored targeted analyses. Water quality managers in California have embraced this strategy with plans to further develop and test this framework in regional and statewide pilot studies on waterbodies that receive discharge from municipal wastewater treatment plants and stormwater runoff. In addition to directly informing decisions, the data obtained using this framework can be used to construct and validate models that better predict CEC occurrence and toxicity. The adaptive interplay among screening results, diagnostic assessment and predictive modeling will allow managers to make decisions based on the most current and relevant information, instead of extrapolating from parameters with questionable linkage to CEC impacts. Integr Environ Assess Manag 2016;12:540-547. © 2015 SETAC. PMID:26426153

  10. Uptake and release kinetics of 134Cs by goldfish (Carassius auratus) and 137Cs by zebra fish (Brachydanio rerio) in controlled aquatic environment

    International Nuclear Information System (INIS)

    The uptake and release kinetics of 134Cs by Goldfish (Carassius auratus) and 137Cs by Zebra Fish (Brachydanio rerio) from aquatic media of different ionic compositions and temperature was studied in controlled laboratory conditions. The accumulation of radiocesium in the case of Brachydanio rerio is observed to be strongly dependent on the potassium ion concentration of the aquatic medium, but in the case of Carassius auratus this dependence is quite weak. The biological half-lives of the cesium isotopes incorporated into the fish investigated in the present work vary from 19 to 80 days and are influenced by the temperature and the ionic composition of the aquatic medium. (author) 19 refs.; 1 fig.; 3 tabs

  11. Strategies for Transferring Mixtures of Organic Contaminants from Aquatic Environments into Bioassays.

    Science.gov (United States)

    Jahnke, Annika; Mayer, Philipp; Schäfer, Sabine; Witt, Gesine; Haase, Nora; Escher, Beate I

    2016-06-01

    Mixtures of organic contaminants are ubiquitous in the environment. Depending on their persistence and physicochemical properties, individual chemicals that make up the mixture partition and distribute within the environment and might then jointly elicit toxicological effects. For the assessment and monitoring of such mixtures, a variety of cell-based in vitro and low-complexity in vivo bioassays based on algae, daphnids or fish embryos are available. A very important and sometimes unrecognized challenge is how to combine sampling, extraction and dosing to transfer the mixtures from the environment into bioassays, while conserving (or re-establishing) their chemical composition at adjustable levels for concentration-effect assessment. This article outlines various strategies for quantifiable transfer from environmental samples including water, sediment, and biota into bioassays using total extraction or polymer-based passive sampling combined with either solvent spiking or passive dosing. PMID:26804122

  12. Strategies for Transferring Mixtures of Organic Contaminants from Aquatic Environments into Bioassays

    DEFF Research Database (Denmark)

    Jahnke, Annika; Mayer, Philipp; Schäfer, Sabine;

    2016-01-01

    Mixtures of organic contaminants are ubiquitous in the environment. Depending on their persistence and physicochemical properties, individual chemicals that make up the mixture partition and distribute within the environment and might then jointly elicit toxicological effects. For the assessment...... and monitoring of such mixtures, a variety of cell-based in vitro and low-complexity in vivo bioassays based on algae, daphnids or fish embryos are available. A very important and sometimes unrecognized challenge is how to combine sampling, extraction and dosing to transfer the mixtures from the...... environment into bioassays, while conserving (or re-establishing) their chemical composition at adjustable levels for concentration-effect assessment. This article outlines various strategies for quantifiable transfer from environmental samples including water, sediment, and biota into bioassays using total...

  13. Comparative studies of the global ecological state variation of the aquatic environment in the Crişuri Hydrographic Space between 2007 and 2009

    Directory of Open Access Journals (Sweden)

    Corina Sion

    2011-04-01

    Full Text Available The paper presents a comparative study regarding the evolution across time of the quality of aquatic eco-systems in the Crişuri Hydrographic Space (CHS, between 2007 and 2009. Having as a goal a real and complete image of the quality of the environment in the CHS, the ecological monitoringconducted was meant to observe the structure of the aquatic communities (macrozoobenthos, microphytobenthos, phytoplankton and the biotope characteristics (physical and chemical parameters of water: pH, conductivity, dissolved oxygen, CBO5, CCO-Mn, CCO-Cr, nitrites, nitrates, phosphates, amonium, chlorophyll “a”, chlorides, sulphates, fix residues, As, Hg, Cu, Zn, Mn, phenols, detergents etc. The choosing of the monitoring sections, their identification and geographical position were accomplished in 2006. The basic criterion in the choice of the monitoring sections was the identification of all aspects that can influence the quality state of the waters. The monitoring of the quality state of the waters in the CHS was conducted in 40 sections, both on the main courses and their affluents, over a 3-year period. After the results of the analyses of physico-chemical and biological samples were obtained, the categorization of the prelevation sections in quality classes followed; depending on these classes, the modelation of the global ecological states of the watercourses in the CHS was realized by means of mapping techniques (GIS. Most of the monitoring sections were in the good ecological state category. The very good ecological state was determined only for those sections upstream all polluting sources. Nevertheless, some of the prelevation points exceeded both physico-chemically and biologically the limits of the good quality state, entering the category of moderate quality state. No watercourse in the CHS was determined for poor or bad quality state. Generally, a “preservation” of the quality state of the waters from one year to the following was

  14. A novel triplex quantitative PCR strategy for quantification of toxigenic and nontoxigenic Vibrio cholerae in aquatic environments.

    Science.gov (United States)

    Bliem, Rupert; Schauer, Sonja; Plicka, Helga; Obwaller, Adelheid; Sommer, Regina; Steinrigl, Adolf; Alam, Munirul; Reischer, Georg H; Farnleitner, Andreas H; Kirschner, Alexander

    2015-05-01

    Vibrio cholerae is a severe human pathogen and a frequent member of aquatic ecosystems. Quantification of V. cholerae in environmental water samples is therefore fundamental for ecological studies and health risk assessment. Beside time-consuming cultivation techniques, quantitative PCR (qPCR) has the potential to provide reliable quantitative data and offers the opportunity to quantify multiple targets simultaneously. A novel triplex qPCR strategy was developed in order to simultaneously quantify toxigenic and nontoxigenic V. cholerae in environmental water samples. To obtain quality-controlled PCR results, an internal amplification control was included. The qPCR assay was specific, highly sensitive, and quantitative across the tested 5-log dynamic range down to a method detection limit of 5 copies per reaction. Repeatability and reproducibility were high for all three tested target genes. For environmental application, global DNA recovery (GR) rates were assessed for drinking water, river water, and water from different lakes. GR rates ranged from 1.6% to 76.4% and were dependent on the environmental background. Uncorrected and GR-corrected V. cholerae abundances were determined in two lakes with extremely high turbidity. Uncorrected abundances ranged from 4.6×10(2) to 2.3×10(4) cell equivalents liter(-1), whereas GR-corrected abundances ranged from 4.7×10(3) to 1.6×10(6) cell equivalents liter(-1). GR-corrected qPCR results were in good agreement with an independent cell-based direct detection method but were up to 1.6 log higher than cultivation-based abundances. We recommend the newly developed triplex qPCR strategy as a powerful tool to simultaneously quantify toxigenic and nontoxigenic V. cholerae in various aquatic environments for ecological studies as well as for risk assessment programs. PMID:25724966

  15. Passive sampling in regulatory chemical monitoring of nonpolar organic compounds in the aquatic environment

    NARCIS (Netherlands)

    Booij, K.; Robinson, C.D.; Burgess, R.M.; Mayer, P.; Roberts, C.A.; Ahrens, L.; Allan, I.J.; Brant, J.; Jones, L.; Kraus, U.R.; Larsen, M.M.; Lepom, P.; Petersen, J.; Pröfrock, D.; Roose, P.; Schäfer, S.; Smedes, F.; Tixier, C.; Vorkamp, K.; Whitehouse, P.

    2016-01-01

    We reviewed compliance monitoring requirements in the EuropeanUnion, the United States, and the Oslo-Paris Convention for the protection of themarine environment of the North-East Atlantic, and evaluated if these are met bypassive sampling methods for nonpolar compounds. The strengths andshortcoming

  16. Passive Sampling in Regulatory Chemical Monitoring of Nonpolar Organic Compounds in the Aquatic Environment

    Science.gov (United States)

    We reviewed compliance monitoring requirements in the European Union (EU), the United States(USA), and the Oslo-Paris Convention for the protection of the marine environment of the North-East Atlantic (OSPAR), and evaluated if these are met by passive sampling methods for nonpola...

  17. Antibiotic contamination and occurrence of antibiotic-resistant bacteria in aquatic environments of northern Vietnam.

    Science.gov (United States)

    Hoa, Phan Thi Phuong; Managaki, Satoshi; Nakada, Norihide; Takada, Hideshige; Shimizu, Akiko; Anh, Duong Hong; Viet, Pham Hung; Suzuki, Satoru

    2011-07-01

    The ubiquitous application and release of antibiotics to the environment can result in bacterial antibiotic resistance, which in turn can be a serious risk to humans and other animals. Southeast Asian countries commonly apply an integrated recycling farm system called VAC (Vegetable, Aquaculture and Caged animal). In the VAC environment, antibiotics are released from animal and human origins, which would cause antibiotic-resistant bacteria (ARB). This study evaluated occurrence of ARB in the VAC environment in northern Vietnam, with quantitative analysis of antibiotic pollution. We found that sulfonamides were commonly detected at all sites. In dry season, while sulfamethazine was a major contaminant in pig farm pond (475-6662 ng/l) and less common in city canal and aquaculture sites, sulfamethoxazole was a major one in city canal (612-4330 ng/l). Erythromycin (154-2246 ng/l) and clarithromycin (2.8-778 ng/ml) were the common macrolides in city canal, but very low concentrations in pig farm pond and aquaculture sites. High frequencies of sulfamethoxazole-resistant bacteria (2.14-94.44%) were found whereas the occurrence rates of erythromycin-resistant bacteria were lower (Aeromonas were the major genera. Twenty three of 25 genera contained sul genes. This study showed specific contamination patterns in city and VAC environments and concluded that ARB occurred not only within contaminated sites but also those less contaminated. Various species can obtain resistance in VAC environment, which would be reservoir of drug resistance genes. Occurrence of ARB is suggested to relate with rainfall condition and horizontal gene transfer in diverse microbial community. PMID:21669325

  18. Tritium in the aquatic environment and the associated risk; Le tritium dans le milieu aquatique et le risque associe

    Energy Technology Data Exchange (ETDEWEB)

    Tort, V.; Lefaure, C. [Centre d`Etude sur l`Evaluation de la Protection dans le Domaine Nucleaire, 92 - Fontenay-aux-Roses (France); Linden, G.; Herbelet, J. [Office de Protection contre les Rayonnements Ionisants, 78 - le Vesinet (France)

    1997-10-01

    Tritium, which is naturally present in the environment under tritiated water form, participates to the global water cycle. Today, nuclear fuel cycle facilities represent the main source of man-made tritium. The civilian production is estimated to be about 2 x 10{sup 4} TBq/y, corresponding to a third of the natural production. Due to the fact that tritium releases are very local, concentrations in water higher than natural background (of 0.1 to 0.9 Bq/l for surface waters) are observed around these sites. Measurements in French aquatic environment reveal tritium concentration generally below 10 Bq/1 for underground waters and below 20 Bq/l for rivers. Nevertheless, some ground waters and some rivers presents locally a concentration up to a few hundreds of Bq/l. Moreover, measurements performed in France are generally coherent with monitoring in other European countries. Furthermore, the associated radiological impact for a potential individual taking all this water needs from a 100 Bq/l tritiated water source, was evaluated to about one thousandth of the natural background. (authors)

  19. The radiological consequences of releases from nuclear facilities to the aquatic environment

    International Nuclear Information System (INIS)

    The release of radioactive materials to the environment is an inescapable consequence of the utilization of nuclear energy. The objective therefore is to decide on what basis and against what criteria regulatory action should be taken to protect the environment against the impact of radioactive substances. In properly regulated situations releases of such material will be minor in character and their radiological implications will rest largely in the field of public health. There are now some three decades of experience in respect of the environmental impact of radioactive materials, and certain major conclusions can be drawn. This paper reviews this experience in broad terms, and draws conclusions relevant to the regulatory problem. Future problems, especially in the context of an expanding use of nuclear power, are considered and priority research needs and opportunities indicated. (author)

  20. Passive sampling of pharmaceuticals and personal care products in aquatic environments

    OpenAIRE

    Zdena Křesinová; Klára Petrů; Ondřej Lhotský; Torgeir Rodsand; Tomáš Cajthaml

    2016-01-01

    Passive sampling is a rapidly developing technology, which is widely used for the monitoring of pollutants in different environments. Passive sampling offers significant advantages over traditional grab sampling. In the present review, the authors summarize the current literature on the methods of passive sampling used in the environmental monitoring of polar or semi-polar compounds in aqueous matrices. Methods of calibrating, design and deployment of samplers are also discussed. A major focu...

  1. Ecological limitations on aquatic mosquito predator colonization in the urban environment

    OpenAIRE

    Carlson, John; Keating, Joseph; Mbogo, Charles M; Kahindi, Samuel; Beier, John C

    2004-01-01

    Urban malaria cases are becoming common in Africa as more people move into cities and industrialization proceeds. While many species of Anopheles mosquitoes vector malaria in rural areas, only a few are found within cities. The success of anthropophilic species in cities, such as members of the An. gambiae complex, may be explained by limitations on colonization by predator species in urban environments. Habitats that are temporal or structurally simple have lower predator survivorship in a v...

  2. A genetically explicit model of speciation by sensory drive within a continuous population in aquatic environments

    OpenAIRE

    Kawata, Masakado; Shoji, Ayako; Kawamura, Shoji; Seehausen, Ole

    2007-01-01

    BACKGROUND: The sensory drive hypothesis predicts that divergent sensory adaptation in different habitats may lead to premating isolation upon secondary contact of populations. Speciation by sensory drive has traditionally been treated as a special case of speciation as a byproduct of adaptation to divergent environments in geographically isolated populations. However, if habitats are heterogeneous, local adaptation in the sensory systems may cause the emergence of reproductively isolated spe...

  3. A genetically explicit model of speciation by sensory drive within a continuous population in aquatic environments

    OpenAIRE

    Seehausen Ole; Kawamura Shoji; Shoji Ayako; Kawata Masakado

    2007-01-01

    Abstract Background The sensory drive hypothesis predicts that divergent sensory adaptation in different habitats may lead to premating isolation upon secondary contact of populations. Speciation by sensory drive has traditionally been treated as a special case of speciation as a byproduct of adaptation to divergent environments in geographically isolated populations. However, if habitats are heterogeneous, local adaptation in the sensory systems may cause the emergence of reproductively isol...

  4. Observation and characterization of mode splitting in microsphere resonators in aquatic environment

    OpenAIRE

    Woosung, Kim; Ozdemir, Sahin Kaya; Zhu, Jiangang; Yang, Lan

    2011-01-01

    Whispering gallery mode (WGM) optical resonators utilizing resonance shift (RS) and mode splitting (MS) techniques have emerged as highly sensitive platforms for label-free detection of nano-scale objects. RS method has been demonstrated in various resonators in air and liquid. MS in microsphere resonators has not been achieved in aqueous environment up to date, despite its demonstration in microtoroid resonators. Here, we demonstrate scatterer-induced MS of WGMs in microsphere resonators in ...

  5. Cytostatics in the aquatic environment : analysis, occurrence, and possibilities for removal

    OpenAIRE

    Koval'ová, L'ubomíra

    2009-01-01

    Many pharmaceuticals have attracted the attention of environmental scientists and are of concern due to their observed occurrence in surface water, ground water, drinking water, sediment, and soil. Further investigations have considered their removal efficiencies in wastewater treatment processes and their ecotoxicological effects. Cytostatics are a class of pharmaceuticals used in the treatment of cancer and have the potential to negatively impact the environment. It is hypothesized that due...

  6. Passive Sampling in Regulatory Chemical Monitoring of Nonpolar Organic Compounds in the Aquatic Environment

    OpenAIRE

    Booij, Kees; Robinson, Craig D.; Burgess, Robert M.; Mayer, Philipp; Roberts, Cindy A; Ahrens, Lutz; Allan, Ian J; Brant, Jan; Jones, Lisa; Kraus, Uta R.; Larsen, Martin M.; Lepom, Peter; Petersen, Jördis; Pröfrock, Daniel; Roose, Patrick

    2016-01-01

    We reviewed compliance monitoring requirements in the European Union, the United States, and the Oslo-Paris Convention for the protection of the marine environment of the North-East Atlantic, and evaluated if these are met by passive sampling methods for nonpolar compounds. The strengths and shortcomings of passive sampling are assessed for water, sediments, and biota. Passive water sampling is a suitable technique for measuring concentrations of freely dissolved compounds. This method yields...

  7. Occurrence, sources, and fate of pharmaceuticals in aquatic environment and soil

    International Nuclear Information System (INIS)

    With the rapid economic development, a better living condition leads to longer life expectancy, which increased the total population, in particular the elderly group. It may result in increase in the demand of pharmaceuticals for people in domestic use or in hospital. Although most sewage treatment plants or waste water treatment plantsmet the regulatory requirement, there are still many pharmaceuticals removed incompletely and thus discharged to the environment. Therefore, the pharmaceuticals residue draws the public concern because they might cause adverse effects on the organism even human beings. Recently, many studies have published on the source and occurrence as well as the fate of pharmaceuticals all over the world. This paper summarized and reviewed the recent studies on the sources, occurrence, fate and the effects of the most common pharmaceuticals. Finally, it gave the suggestion and risk management for controlling the pharmaceuticals. - Highlights: • The sources of pharmaceutical residuals are studied. • Occurrence and fate of pharmaceutical in environment are studied. • Risk management and recommendation are provided on pharmaceutical pollution. - Concentration of pharmaceuticals in the natural environment is lower than in effluent of sewage treatment plants in which carbamazepine is found frequently in soil and water body

  8. Tungsten and other heavy metal contamination in aquatic environments receiving wastewater from semiconductor manufacturing

    International Nuclear Information System (INIS)

    Through analyses of water and sediments, we investigate tungsten and 14 other heavy metals in a stream receiving treated effluents from a semiconductor manufacturer-clustered science park in Taiwan. Treated effluents account for ∼50% of total annual river discharge and <1% of total sediment discharge. Dissolved tungsten concentrations in the effluents abnormally reach 400 μg/L, as compared to the world river average concentration of <0.1 μg/L. Particulate tungsten concentrations are up to 300 μg/g in suspended and deposited sediments, and the corresponding enrichment factors are three orders of magnitude higher than average crust composition. Surprisingly, the estimated amount of tungsten exported to the adjacent ocean is 23.5 t/yr, which can approximate the amount from the Yangtze River should it be unpolluted. This study highlights the urgency of investigating the biological effect of such contamination.

  9. A laboratory experiment on the behaviour of soil-derived core and intact polar GDGTs in aquatic environments

    Science.gov (United States)

    Peterse, F.; Moy, C. M.; Eglinton, T. I.

    2015-02-01

    We have performed incubation experiments in order to examine the behaviour of soil-derived branched glycerol dialkyl glycerol tetraether (brGDGT) membrane lipids upon entering an aquatic environment and to evaluate the processes that potentially take place during their fluvial transport from land to sea. We incubated a soil from the Rakaia River catchment on the South Island of New Zealand using Rakaia River water and ocean water collected near the river mouth as inocula for a period of up to 152 days. The concentrations, as well as the relative distribution of brGDGTs derived from intact polar ("living"; IPL) lipids and core ("fossil"; CL) lipids remained unaltered over the course of the experiment. Although the stability of the brGDGTs may be a consequence of the higher than natural soil : water ratio used in the laboratory experiment, the substantial increase (27-72%) in the total pool of isoprenoid GDGTs (isoGDGTs) in all incubation setups, including the control using distilled water, indicates that entering an aquatic environment does influence the behaviour of soil-derived GDGTs. However, the availability of water appears to be more important than its properties. As a consequence of increasing isoGDGT concentrations, a decrease in Branched and Isoprenoid Tetraether (BIT) index values - a proxy for the relative input of fluvially discharged soil material into a marine system - became evident after an incubation period of 30 days, with a maximum final decrease of 0.88 to 0.74 in the experiment with river water. The relative distribution within the isoGDGT pool shows changes with time, suggesting that isoGDGT producers may either have different rates of membrane adaptation or production/degradation, or that preferential release from the soil matrix or a shift in source organism(s) may take place. While the apparent stability of soil brGDGTs during this incubation experiment reinforces their potential as tracers for land-sea transport of soil organic carbon and

  10. Distribution and Characterization of Kepone-Resistant Bacteria in the Aquatic Environment

    OpenAIRE

    Orndorff, S. A.; Colwell, R R

    1980-01-01

    Effects of the chlorinated insecticide Kepone on the ecology of Chesapeake Bay and James River bacteria were studied. Kepone-resistant bacteria present in a given environment were found to reflect the degree of fecal and/or high organic pollution of the sampling sites, based on total numbers and generic composition of the populations of Kepone-resistant bacteria. The presence of Kepone-resistant bacteria was found to be correlated (α = 0.01) with total coliforms, fecal coliforms, and total ae...

  11. Subject-3: Study on migration of radionuclides released into terrestrial and aquatic environment after nuclear accident

    International Nuclear Information System (INIS)

    Subject-3 has been focused on the migration behavior of long-lived radionuclides in the terrestrial surface environment, especially in connection with their chemical and physical forms. Migration behavior of radionuclides is strongly affected with their chemical and physical forms (for example; Gunten and Benes 1995). One of the two categories in Subject-3 consists of migration from surface soils including aging effects of hot particles, plant uptake from contaminated soils, and resuspension of radionuclides. The other is run off by river system, considering the role of organic materials. (author)

  12. Observation and characterization of mode splitting in microsphere resonators in aquatic environment

    CERN Document Server

    Woosung, Kim; Zhu, Jiangang; Yang, Lan

    2011-01-01

    Whispering gallery mode (WGM) optical resonators utilizing resonance shift (RS) and mode splitting (MS) techniques have emerged as highly sensitive platforms for label-free detection of nano-scale objects. RS method has been demonstrated in various resonators in air and liquid. MS in microsphere resonators has not been achieved in aqueous environment up to date, despite its demonstration in microtoroid resonators. Here, we demonstrate scatterer-induced MS of WGMs in microsphere resonators in water. We determine the size range of particles that induces MS in a microsphere in water as a function of resonator mode volume and quality factor. The results are confirmed by the experimental observations.

  13. Subject-3: Study on migration of radionuclides released into terrestrial and aquatic environment after nuclear accident

    Energy Technology Data Exchange (ETDEWEB)

    Amano, H.; Matsunaga, T.; Ueno, T.; Nagao, S.; Yanase, N. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Arkhipov, A.N. [Chernobyl Scientific and Technical Center for International Research (Ukraine); Tkachenko, Yu. [The State Enterprise Regional Monitoring and Domestic Control (RADEC) (Unknown)

    2001-03-01

    Subject-3 has been focused on the migration behavior of long-lived radionuclides in the terrestrial surface environment, especially in connection with their chemical and physical forms. Migration behavior of radionuclides is strongly affected with their chemical and physical forms (for example; Gunten and Benes 1995). One of the two categories in Subject-3 consists of migration from surface soils including aging effects of hot particles, plant uptake from contaminated soils, and resuspension of radionuclides. The other is run off by river system, considering the role of organic materials. (author)

  14. Antibiotic resistance among aquatic bacteria in natural freshwater environments of Korea.

    Science.gov (United States)

    Kim, Tae Woon; Joung, Yochan; Han, Ji-Hye; Jung, Wonwha; Kim, Seung Bum

    2015-12-01

    The taxonomic diversity and antibiotic resistance among freshwater bacterial communities in the major water bodies of Korea was examined using 437 penicillin-resistant, and 110 tetracycline-resistant bacterial isolates. Based on 16S rRNA gene sequence analysis, most isolates were assigned to Proteobacteria, which was then followed by Bacteroidetes. Strains of Aeromonas were found as the most abundant penicillin-resistant populations, whereas those affiliated to diverse species including enteric groups were found as the most abundant tetracycline-resistant populations. Most strains exhibited multiple antibiotic resistance, and all tested strains were resistant to penicillin and hygromycin. High levels of resistance were observed for antibiotics acting on cell wall synthesis, whereas low levels were for those acting on DNA replication or transcription in general. It is apparent from this study that penicillin resistance is widespread among environmental bacteria, although the antibiotic has been generally non-detectable in the environment. It is also likely from the taxonomic composition of the resistant communities that various sources including terrestrial animals and humans may contribute to antibiotic resistance in the freshwater environment. PMID:26608770

  15. Aggregation and resuspension of graphene oxide in simulated natural surface aquatic environments

    International Nuclear Information System (INIS)

    A series of experiments were performed to simulate the environmental behavior and fate of graphene oxide nanoparticles (GONPs) involved in the surface environment relating to divalent cations, natural organic matter (NOM), and hydraulics. The electrokinetic properties and hydrodynamic diameters of GONPs was systematically determined to characterize GONPs stability and the results indicated Ca2+ (Mg2+) significantly destabilized GONPs with high aggregate strength factors (SF) and fractal dimension (FD), whereas NOM decreased aggregate SF with lower FD and improved GONPs stability primarily because of increasing steric repulsion and electrostatic repulsion. Furthermore, the GONPs resuspension from the sand bed into overlying water with shear flow confirmed that the release would be restricted by Ca2+ (Mg2+), however, enhanced by NOM. The interaction energy based on Derjaguin–Landau–Verwey–Overbeek theory verifies the aggregation and resuspension well. Overall, these experiments provide an innovative look and more details to study the behavior and fate of GONPs. - Highlights: • Aggregation and resuspension of GONPs relating to surface environment are presented. • Aggregate strength factors of GONPs aggregates are quantitated by breakage experiment. • Compactness of the aggregates is closely related to fractal dimension. • Models for GONPs aggregation and breakage are synthetically proposed. • Interaction energy based on DLVO theory could interpret aggregation and resuspension of GONPs. - Aggregation and resuspension of graphene oxide relating to divalent cations, natural organic matter (NOM), and hydraulics are investigated based on DLVO theory

  16. Allelopathy of Aquatic Autotrophs

    OpenAIRE

    Gross, Elisabeth

    2003-01-01

    Allelopathy in aquatic environments may provide a competitive advantage to angiosperms, algae, or cyanobacteria in their interaction with other primary producers. Allelopathy can influence the competition between different photoautotrophs for resources and change the succession of species, for exarnple, in phytoplankton cornmunities. Field evidence and laboratory studies indicate that allelopathy occurs in all aquatic habitats (marine and freshwater), and that ail prirnary producing organisms...

  17. Comparative radiological and conventional pollution impact recording in the aquatic environment by use of a cytogenetic tool

    International Nuclear Information System (INIS)

    Complete text of publication follows. The effects of ionizing radiation can be viewed at all levels of biological organization, ranging from the molecular to ecosystem level. Effects on organisms can be traced to molecular and cellular responses, as radiation impact does not necessarily lead to observable effects on specimens, population or ecosystem. This is because the measurable attributes of the levels differ, despite the fact that all levels are interrelated. The cytogenetic effects of radioactive and conventional pollution as they are recorded in organisms of natural ecosystem and the apportionment of causes to each kind of pollutants is a relative new field in radioecological research. There is limited evidence on field observations in international literature; even there is a lot of evidence in concerning laboratory experiments. The study of in situ effects of ionizing radiation in the cytogenetic level is the key for determining the radiological status of the ecosystem considered, based on the relation: concentration of pollutant in abiotic components and/or bioaccumulation → dose rate → effect on organism at the cellular level. Several field studies on the comparative effects of ionizing radiation and chemical pollution in some selected areas in the Mediterranean, the Black Sea and in inland waters combined with laboratory experiments have shown a conceptual model of response of organisms, which is unique for ionizing radiation and chemical pollution. This model is based on the effects of different pollutants on aquatic biota (Crustacea, Polychaeta, Oligochatea, Fish embryos etc), as they have been recorded at the cellular level. The environmental assessment of an aquatic ecosystem with regards to ionizing radiation in comparison to effects of chemical pollutants is based on determining the distribution frequency of chromosomal aberrations induced in cells of natural populations. Cytogenetic methods are used in pollution research because of their high

  18. Passive aquatic listener (PAL): An adoptive underwater acoustic recording system for the marine environment

    International Nuclear Information System (INIS)

    The ambient sound field in the ocean is a combination of natural and manmade sounds. Consequently, the interpretation of the ambient sound field can be used to quantify these processes. In the frequency range from 1 to 50 kHz, the general character of ocean ambient sound is a slowly changing background that is closely associated with local wind speed, interspersed with shorter time scale events such as rain storms, ships and animal calls. At lower frequencies the underwater ambient sound budget includes geologically generated sound activities including underwater volcanic eruptions, seismic and seepage faults that generate bubbles, etc. that can also potentially be classified and quantified. Acoustic data are collected on hydrophones. Hydrophones are simple, robust sensors that can be deployed on most ocean instrumentation systems including surface or sub-surface moorings, bottom mounted systems, drifters, ARGO floats or autonomous underwater platforms. A dedicated oceanic underwater recorder called a passive acoustic listener (PAL) has been developed. A principal issue is to accurately distinguish different sound sources so that they can be quantified as part of a sound budget, and then quantified if appropriate. Based on ongoing data collected from the Poseidon II network the retrieval potential of multi-parameters from underwater sound, including meteorological (i.e., precipitation and winds) and in general geophysical, anthropogenetic (i.e., ships, submarines, etc.) and biological (whales, etc.) sources is presented.

  19. Passive aquatic listener (PAL): An adoptive underwater acoustic recording system for the marine environment

    Energy Technology Data Exchange (ETDEWEB)

    Anagnostou, Marios N., E-mail: managnostou@ath.hcmr.g [Hellenic Center for Marine Research, Department of Inland Waters, Anavissos (Greece); Nystuen, Jeffrey A. [Hellenic Center for Marine Research, Department of Inland Waters, Anavissos (Greece); Applied Physics Laboratory, University of Washington, Seattle, WA (United States); Anagnostou, Emmanouil N. [Hellenic Center for Marine Research, Department of Inland Waters, Anavissos (Greece); Department of Civil and Environmental Engineering, University of Connecticut, CT (United States); Papadopoulos, Anastasios [Hellenic Center for Marine Research, Department of Inland Waters, Anavissos (Greece); Lykousis, Vassilios [Hellenic Center for Marine Research, Department of Oceanography, Anavissos (Greece)

    2011-01-21

    The ambient sound field in the ocean is a combination of natural and manmade sounds. Consequently, the interpretation of the ambient sound field can be used to quantify these processes. In the frequency range from 1 to 50 kHz, the general character of ocean ambient sound is a slowly changing background that is closely associated with local wind speed, interspersed with shorter time scale events such as rain storms, ships and animal calls. At lower frequencies the underwater ambient sound budget includes geologically generated sound activities including underwater volcanic eruptions, seismic and seepage faults that generate bubbles, etc. that can also potentially be classified and quantified. Acoustic data are collected on hydrophones. Hydrophones are simple, robust sensors that can be deployed on most ocean instrumentation systems including surface or sub-surface moorings, bottom mounted systems, drifters, ARGO floats or autonomous underwater platforms. A dedicated oceanic underwater recorder called a passive acoustic listener (PAL) has been developed. A principal issue is to accurately distinguish different sound sources so that they can be quantified as part of a sound budget, and then quantified if appropriate. Based on ongoing data collected from the Poseidon II network the retrieval potential of multi-parameters from underwater sound, including meteorological (i.e., precipitation and winds) and in general geophysical, anthropogenetic (i.e., ships, submarines, etc.) and biological (whales, etc.) sources is presented.

  20. The Relationship between Grade 11 Palestinian Attitudes toward Biology and Their Perceptions of the Biology Learning Environment

    Science.gov (United States)

    Zeidan, Afif

    2010-01-01

    The aims of the study were to investigate (a) the relationship between the attitudes toward biology and perceptions of the biology learning environment among grade 11 students in Tulkarm District, Palestine and (b) the effect of gender and residence of these students on their attitudes toward biology and on their perceptions of the biology…

  1. Determination of coal tar and creosote constituents in the aquatic environment

    International Nuclear Information System (INIS)

    Creosote and its parent material, coal tar, are complex mixtures. Assessment of their fate and concentrations in the environment needs to consider a wide variety of both compounds and matrices. Analyses are typically complicated, consisting of sample extraction, purification and chromatography-based final characterization steps. Several new techniques have been introduced to reduce or simplify the number of steps, solvent and time required. Recently developed extraction methods include supercritical fluid, accelerated solvent, microwave and solid-phase microextraction. On-line purification and coupling of extraction and chromatography have also emerged. HPLC and GC remain the major tools for performing the final separations. Application of mass spectrometry has increased as more reliable, versatile and less expensive units have become available, such as the ion trap and mass selective detectors. Fluorescence and diode array UV, in concert with HPLC, and C-, S- and N-selective gas chromatographic detectors are also being applied

  2. Radiation effects on biological molecules: Influence of the local environment

    International Nuclear Information System (INIS)

    Because it crystallizes with several different molecular environments (e.g. hydrated, anhydrous, and HCl), and in several slightly modified molecular forms, the amino acid proline has been chosen as a probe of possible local effects on the radiation chemistry of biological molecules. In all systems studied so far (proline, proline/sup ./H/sub 2/O, proline /sup ./HCl, hydroxyl-proline, thioproline, and oxoproline), evidence for the ''deamination'' radical has been detected. This product, shown to arise from the primary carboxyl anion in hydroxyproline, is probably the result of electron attack in the other cases, also from the α-carbon. Evidence for the other products is currently under analysis and is discussed along with a summary of the results

  3. Adsorption of biometals to monosodium titanate in biological environments

    Energy Technology Data Exchange (ETDEWEB)

    HOBBS, D.T.; MESSER, R. L. W.; LEWIS, J. B.; CLICK, D. R. LOCKWOOD, P. E.; WATAHA, J. C.

    2005-06-06

    Monosodium titanate (MST) is an inorganic sorbent/ion exchanger developed for the removal of radionuclides from nuclear wastes. We investigated the ability of MST to bind Cd(II), Hg(II), or Au(III) to establish the utility of MST for applications in environmental decontamination or medical therapy (drug delivery). Adsorption isotherms for MST were determined at pH 7-7.5 in water or phosphate-buffered saline. The extent of metal binding was determined spectroscopically by measuring the concentrations of the metals in solution before and after contact with the MST. Cytotoxic responses to MST were assessed using THP1 monocytes and succinate dehydrogenase activity. Monocytic activation by MST was assessed by TNF{alpha} secretion (ELISA) with or without lipopolysaccharide (LPS) activation. MST sorbed Cd(II), Hg(II), and Au(III) under conditions similar to that in physiological systems. MST exhibited the highest affinity for Cd(II) followed by Hg(II) and Au (III). MST (up to 100 mg/L) exhibited only minor (< 25% suppression of succinate dehydrogenase) cytotoxicity and did not trigger TNF{alpha} secretion nor modulate LPS-induced TNF{alpha} secretion from monocytes. MST exhibits high affinity for biometals with no significant biological liabilities in these introductory studies. MST deserves further scrutiny as a substance with the capacity to decontaminate biological environments or deliver metals in a controlled fashion.

  4. Use of quantitative real-time PCR for direct detection of serratia marcescens in marine and other aquatic environments.

    Science.gov (United States)

    Joyner, Jessica; Wanless, David; Sinigalliano, Christopher D; Lipp, Erin K

    2014-03-01

    Serratia marcescens is the etiological agent of acroporid serratiosis, a distinct form of white pox disease in the threatened coral Acropora palmata. The pathogen is commonly found in untreated human waste in the Florida Keys, which may contaminate both nearshore and offshore waters. Currently there is no direct method for detection of this bacterium in the aquatic or reef environment, and culture-based techniques may underestimate its abundance in marine waters. A quantitative real-time PCR assay was developed to detect S. marcescens directly from environmental samples, including marine water, coral mucus, sponge tissue, and wastewater. The assay targeted the luxS gene and was able to distinguish S. marcescens from other Serratia species with a reliable quantitative limit of detection of 10 cell equivalents (CE) per reaction. The method could routinely discern the presence of S. marcescens for as few as 3 CE per reaction, but it could not be reliably quantified at this level. The assay detected environmental S. marcescens in complex sewage influent samples at up to 761 CE ml(-1) and in septic system-impacted residential canals in the Florida Keys at up to 4.1 CE ml(-1). This detection assay provided rapid quantitative abilities and good sensitivity and specificity, which should offer an important tool for monitoring this ubiquitous pathogen that can potentially impact both human health and coral health. PMID:24375136

  5. Development of short, acute exposure hazard estimates: a tool for assessing the effects of chemical spills in aquatic environments.

    Science.gov (United States)

    Bejarano, Adriana C; Farr, James K

    2013-08-01

    Management decisions aimed at protecting aquatic resources following accidental chemical spills into rivers and coastal estuaries require estimates of toxic thresholds derived from realistic spill conditions: acute pulse exposures of short duration (h), information which often is unavailable. Most existing toxicity data (median lethal concentration or median effective concentration) come from tests performed under constant exposure concentrations and exposure durations in the 24-h to 96-h range, conditions not typical of most chemical spills. Short-exposure hazard concentration estimates were derived for selected chemicals using empirical toxicity data. Chemical-specific 5th percentile hazard concentrations (HC5) of species sensitivity distributions (SSD) from individual exposure durations (6-96 h) were derived via bootstrap resampling and were plotted against their original exposure durations to estimate HC5s and 95% confidence intervals (CIs) at shorter exposures (1, 2, and 4 h). This approach allowed the development of short-exposure HC5s for 12 chemicals. Model verification showed agreement between observed and estimated short-exposure HC5s (r(2) adjusted = 0.95, p overprotective, these were derived from environmentally realistic exposure durations, providing risk-assessors with a tool to manage field decisions. Environ Toxicol Chem 2013;32:1918-1927. © 2013 SETAC. PMID:23625642

  6. Development of a biologically inspired multi-modal wing model for aerial-aquatic robotic vehicles through empirical and numerical modelling of the common guillemot, Uria aalge

    International Nuclear Information System (INIS)

    The common guillemot, Uria aalge, a member of the auk family of seabirds exhibits locomotive capabilities in both aerial and aquatic substrates. Simplistic forms of this ability have yet to be achieved by robotic vehicle designs and offer significant potential as inspiration for future concept designs. In this investigation, we initially investigate the power requirements of the guillemot associated with different modes of locomotion, empirically determining the saving associated with the retraction of the wing during aquatic operations. A numerical model of a morphing wing is then created to allow power requirements to be determined for different wing orientations, taking into account the complex kinematic and inertial dynamics associated with the motion. Validation of the numerical model is achieved by comparisons with the actual behaviour of the guillemot, which is done by considering specific mission tasks, where by the optimal solutions are found utilizing an evolutionary algorithm, which are found to be in close agreement with the biological case.

  7. Radiocesium retention in the aquatic, terrestrial and urban environment: a quantitative and unifying analysis

    International Nuclear Information System (INIS)

    The frayed edges of 10 A phyllosilicates (micaceous minerals), responsible for the highly selective sorption of poorly hydrated alkali cations (Cs, Rb, K) in NH$/sb4$, are quantitatively characterized by masking the planar sites with silver-thiourea. Both the capacity of the frayed edge sites (FES) and the Cs-to-K selectivity coefficient of these sites can be measured. The loading dependence of the Cs-to-K selectivity coefficient in the FES of 4 micaceous minerals demonstrates a pronounced degree of heterogeneity. Only a small fraction of the FES ($<$10%) exhibits extremely high Cs preference. For studying complex mineralogical systems (soils, sediments, rocks and ceramics) a new parameter is introduced: the ''radiocesium interception potential'', defined as the product of FES capacity and the Cs-to-K (or NH$/sb4$) selectivity coefficient in the FES at ''zero'' Cs loading. This parameter is a powerful tool in describing and predicting the highly selective sorption processes in the FES. Under freshwater conditions the radiocesium distribution coefficient can be quantitatively predicted by considering a competition with K and NH$/sb4$ in the FES. In a marine environment Na, and to a lesser extent Ca and Mg, also have to be taken into account. Finally, evidences for a redistribution process are given: sorbed Cs ions diffuse to the interlayers of the clay particles. This phenomenon explains the increasing ''fixation'' of radiocesium with time

  8. Antimicrobial-resistant patterns of Escherichia coli and Salmonella strains in the aquatic Lebanese environments

    International Nuclear Information System (INIS)

    This study is the first to be conducted in Lebanon on the isolation and molecular characterization and the antimicrobial resistance profile of environmental pathogenic bacterial strains. Fifty-seven samples of seawater, sediment, crab, and fresh water were collected during the spring and summer seasons of 2003. The isolation of Escherichia coli and Salmonella using appropriate selective media revealed that 94.7% of the tested samples were contaminated with one or both of the tested bacteria. The polymerase chain reaction (PCR) was then used to identify the species of both bacteria using various sets of primers. Many pathogenic E. coli isolates were detected by PCR out of which two were identified as O157:H7 E. coli. Similarly, the species of many of the Salmonella isolates was molecularly identified. The confirmed isolates of Salmonella and E. coli were then tested using the disk diffusion method for their susceptibility to four different antimicrobials revealing high rates of antimicrobial resistance. - First report of antibiotic resistance in bacteria in the environment in Lebanon

  9. Oxidation of diclofenac with chlorine dioxide in aquatic environments: influences of different nitrogenous species.

    Science.gov (United States)

    Wang, Yingling; Liu, Haijin; Liu, Guoguang; Xie, Youhai; Ni, Tianjun

    2015-06-01

    The oxidation of diclofenac (DCF), a non-steroidal anti-inflammatory drug and emerging water pollutant, with chlorine dioxide was investigated under simulated water disinfection conditions. The reaction kinetics as functions of the initial concentrations of DCF, different nitrogenous species, and different pE values were experimentally determined. The results demonstrated that DCF reacted rapidly with ClO2, where more than 75 % of DCF (≤3.00 μM) was removed by 18.94 μM ClO2 within 60 s. All of the reactions followed pseudo first-order kinetics with respect to DCF, and the rate constant, k obs, exhibited a significant decrease from 4.21 × 10(-2) to 8.09 × 10(-3) s(-1), as the initial DCF concentration was increased from 1.00 to 5.00 μM. Furthermore, the degradation kinetics of DCF was clearly dependent on nitrogen-containing ion concentrations in the reaction solution. Ammonium and nitrite ions inhibited the DCF degradation by ClO2, whereas nitrate ion clearly initiated its promotion. In contrast, the inhibitory effect of NO2 (-) was more robust than that of NH4 (+). When the values of pE were gradually increased, the transformation of NH4 (+) to NO2 (-), and subsequently to NO3 (-), would occur, the rate constants were initially decreased, and then increased. When NH4 (+) and NO2 (-) coexisted, the inhibitory effect on the DCF degradation was less than the sum of the partial inhibitory effect. However, when NO2 (-) and NO3 (-) coexisted, the actual inhibition rate was greater than the theoretical estimate. These results indicated that the interaction of NH4 (+) and NO2 (-) was antagonistic, while the coexistence of NO2 (-) and NO3 (-) was observed to have a synergistic effect in aqueous environments. PMID:25604564

  10. Nonmagnetotactic multicellular prokaryotes from low-saline, nonmarine aquatic environments and their unusual negative phototactic behavior.

    Science.gov (United States)

    Lefèvre, Christopher T; Abreu, Fernanda; Lins, Ulysses; Bazylinski, Dennis A

    2010-05-01

    Magnetotactic multicellular prokaryotes (MMPs) are unique magnetotactic bacteria of the Deltaproteobacteria class and the first found to biomineralize the magnetic mineral greigite (Fe(3)S(4)). Thus far they have been reported only from marine habitats. We questioned whether MMPs exist in low-saline, nonmarine environments. MMPs were observed in samples from shallow springs in the Great Boiling Springs geothermal field and Pyramid Lake, both located in northwestern Nevada. The temperature at all sites was ambient, and salinities ranged from 5 to 11 ppt. These MMPs were not magnetotactic and did not contain magnetosomes (called nMMPs here). nMMPs ranged from 7 to 11 microm in diameter, were composed of about 40 to 60 Gram-negative cells, and were motile by numerous flagella that covered each cell on one side, characteristics similar to those of MMPs. 16S rRNA gene sequences of nMMPs show that they form a separate phylogenetic branch within the MMP group in the Deltaproteobacteria class, probably representing a single species. nMMPs exhibited a negative phototactic behavior to white light and to wavelengths of < or =480 nm (blue). We devised a "light racetrack" to exploit this behavior, which was used to photoconcentrate nMMPs for specific purposes (e.g., DNA extraction) even though their numbers were low in the sample. Our results show that the unique morphology of the MMP is not restricted to marine and magnetotactic prokaryotes. Discovery of nonmagnetotactic forms of the MMP might support the hypothesis that acquisition of the magnetosome genes involves horizontal gene transfer. To our knowledge, this is the first report of phototaxis in bacteria of the Deltaproteobacteria class. PMID:20363801

  11. Towards molecular computers that operate in a biological environment

    Science.gov (United States)

    Kahan, Maya; Gil, Binyamin; Adar, Rivka; Shapiro, Ehud

    2008-07-01

    important consequences when performed in a proper context. We envision that molecular computers that operate in a biological environment can be the basis of “smart drugs”, which are potent drugs that activate only if certain environmental conditions hold. These conditions could include abnormalities in the molecular composition of the biological environment that are indicative of a particular disease. Here we review the research direction that set this vision and attempts to realize it.

  12. Bodies in sequestered and non-sequestered aquatic environments: a comparative taphonomic study using decompositional scoring system.

    Science.gov (United States)

    De Donno, A; Campobasso, C P; Santoro, V; Leonardi, S; Tafuri, S; Introna, F

    2014-12-01

    The study of decomposition by using accumulated degree days (ADDs) has been suggested not only in terrestrial decay but also for water-related deaths. Previous studies have demonstrated that the accumulation of thermal energy as a function of the post-mortem submersion interval (PMSI) can be derived from a descriptive decompositional scoring system (DSS). In order to verify how useful can the total aquatic decomposition score (TADS) for ADD prediction be, a comparative taphonomic study has been performed between two series of bodies: 16 corpses found floating in shallower waters with a presumptive PMSI from 3 to 118 days and exposed to water temperatures (Tw) between 10.5 and 20.3 °C approximately equating from a minimum of 46 to 1.392 ADD; 52 bodies, all victims of a single shipwreck, found in sequestered environments and subjected to constant Tw of 4 °C for 210 days approximately equating to 840 ADD. The two series of bodies have revealed different stages of decay and a large DSS variability. In most of bodies, freshly formed adipocere was able to delay the appearance of later decompositional stages explaining why most of the bodies were in relatively good condition. Although promising, the accuracy of the TADS model can be affected by adipocere and animal activity. The TADS model suffers of the same limitations for ADD calculations as they can give a false perception of accuracy due to the complexity of integrating all changing factors affecting human decay in sequestered and non-sequestered marine environments (currents, animal activity, water temperatures, depth of submersion). PMID:25498931

  13. Sulfonamide and tetracycline resistance genes in total- and culturable-bacterial assemblages in South African aquatic environments

    Science.gov (United States)

    Suzuki, Satoru; Ogo, Mitsuko; Koike, Tatsuya; Takada, Hideshige; Newman, Brent

    2015-01-01

    Antibiotic resistant bacteria are ubiquitous in the natural environment. The introduction of effluent derived antibiotic resistance genes (ARGs) into aquatic environments is of concern in the spreading of genetic risk. This study showed the prevalence of sulfonamide and tetracycline resistance genes, sul1, sul2, sul3, and tet(M), in the total bacterial assemblage and colony forming bacterial assemblage in river and estuarine water and sewage treatment plants (STP) in South Africa. There was no correlation between antibiotic concentrations and ARGs, suggesting the targeted ARGs are spread in a wide area without connection to selection pressure. Among sul genes, sul1 and sul2 were major genes in the total (over 10-2 copies/16S) and colony forming bacteria assemblages (∼10-1 copies/16S). In urban waters, the sul3 gene was mostly not detectable in total and culturable assemblages, suggesting sul3 is not abundant. tet(M) was found in natural assemblages with 10-3 copies/16S level in STP, but was not detected in colony forming bacteria, suggesting the non-culturable (yet-to-be cultured) bacterial community in urban surface waters and STP effluent possess the tet(M) gene. Sulfamethoxazole (SMX) resistant (SMXr) and oxytetracycline (OTC) resistant (OTCr) bacterial communities in urban waters possessed not only sul1 and sul2 but also sul3 and tet(M) genes. These genes are widely distributed in SMXr and OTCr bacteria. In conclusion, urban river and estuarine water and STP effluent in the Durban area were highly contaminated with ARGs, and the yet-to-be cultured bacterial community may act as a non-visible ARG reservoir in certain situations. PMID:26300864

  14. Who possesses drug resistance genes in the aquatic environment?: sulfamethoxazole (SMX) resistance genes among the bacterial community in water environment of Metro-Manila, Philippines

    Science.gov (United States)

    Suzuki, Satoru; Ogo, Mitsuko; Miller, Todd W.; Shimizu, Akiko; Takada, Hideshige; Siringan, Maria Auxilia T.

    2013-01-01

    Recent evidence has shown that antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) are ubiquitous in natural environments, including sites considered pristine. To understand the origin of ARGs and their dynamics, we must first define their actual presence in the natural bacterial assemblage. Here we found varying distribution profiles of sul genes in “colony forming bacterial assemblages” and “natural bacterial assemblages.” Our monitoring for antibiotic contamination revealed that sulfamethoxazole (SMX) is a major contaminant in aquatic environments of Metro-Manila, which would have been derived from human and animal use, and subsequently decreased through the process of outflow from source to the sea. The SMX-resistant bacterial rate evaluated by the colony forming unit showed 10 to 86% of the total colony numbers showed higher rates from freshwater sites compared to marine sites. When sul genes were quantified by qPCR, colony-forming bacteria conveyed sul1 and sul2 genes in freshwater and seawater (10−5–10−2 copy/16S) but not sul3. Among the natural bacterial assemblage, all sul1, sul2, and sul3 were detected (10−5–10−3 copy/16S), whereas all sul genes were at an almost non-detectable level in the freshwater assemblage. This study suggests that sul1 and sul2 are main sul genes in culturable bacteria, whereas sul3 is conveyed by non-culturable bacteria in the sea. As a result marine bacteria possess sul1, sul2 and sul3 genes in the marine environment. PMID:23641240

  15. Persistence of organophosphorus pesticides in aquatic environments. Coordinated programme on isotope-tracer-aided research and monitoring on agricultural residue - biological interactions in aquatic environment

    International Nuclear Information System (INIS)

    A radiometric enzymic assay method was developed for quick measuring of organophosphorous insecticides in water samples. All steps of the assay procedure were carried out in scintillation vials. 50 μl enzyme solution (acetylcholinesterase of electric eel) and 50 μl buffer pH 7 were pipetted into the vial followed by 100 μl of water sample or aqueous solution of the insecticide and the mixture was incubated for 60 minutes. 50 μl 3H-acetylcholine were added to the vial and the enzymic reaction stopped after 10 minutes by adding 200 μl buffer solution pH 2.5. 10 ml scintillation cocktail were then added and after shaking and 30 minutes standing the radioactivity was determined in a liquid scintillation spectrometer. Acetylcholine remained in the water phase while 3H-acetic acid released in enzymic hydrolysis may be extracted by an organic solvent. By this method, not only the parent compound but also some of its degradation products, which possess some anticholinesteratic activity can be measured. The method is suitable for combination with thin-layer chromatography for identification purposes. Using this method, we studied the degradation of the organophosphorous insecticides malathion, parathion, DDVP and imidan. The degradation in distilled water and natural water was compared. For example, the half-time of malathion in distilled water at room temperature was 6 days while in natural water (Danube river) it was 4 hours. The degradation processes were also studied in model systems containing sediment and water. Degradation was faster in models containing solid particles than in filtered water. The radiometric enzymic method was tested as analytical procedure for residue monitoring. Since 1978 a residue monitoring programme was in progress in the Danube river near Budapest. Occasionally high residue levels were detected in spring and early summer. The radiometric enzymic method has proved to be a useful analytical method for anticholinesterase pesticides in water samples. The method allows analysis directly from water samples without extraction or concentration

  16. STSE: Spatio-Temporal Simulation Environment Dedicated to Biology

    Directory of Open Access Journals (Sweden)

    Gerber Susanne

    2011-04-01

    Full Text Available Abstract Background Recently, the availability of high-resolution microscopy together with the advancements in the development of biomarkers as reporters of biomolecular interactions increased the importance of imaging methods in molecular cell biology. These techniques enable the investigation of cellular characteristics like volume, size and geometry as well as volume and geometry of intracellular compartments, and the amount of existing proteins in a spatially resolved manner. Such detailed investigations opened up many new areas of research in the study of spatial, complex and dynamic cellular systems. One of the crucial challenges for the study of such systems is the design of a well stuctured and optimized workflow to provide a systematic and efficient hypothesis verification. Computer Science can efficiently address this task by providing software that facilitates handling, analysis, and evaluation of biological data to the benefit of experimenters and modelers. Results The Spatio-Temporal Simulation Environment (STSE is a set of open-source tools provided to conduct spatio-temporal simulations in discrete structures based on microscopy images. The framework contains modules to digitize, represent, analyze, and mathematically model spatial distributions of biochemical species. Graphical user interface (GUI tools provided with the software enable meshing of the simulation space based on the Voronoi concept. In addition, it supports to automatically acquire spatial information to the mesh from the images based on pixel luminosity (e.g. corresponding to molecular levels from microscopy images. STSE is freely available either as a stand-alone version or included in the linux live distribution Systems Biology Operational Software (SB.OS and can be downloaded from http://www.stse-software.org/. The Python source code as well as a comprehensive user manual and video tutorials are also offered to the research community. We discuss main concepts

  17. The role of physical processes controlling the behaviour of radionuclide contaminants in the aquatic environment: a review of state-of-the-art modelling approaches

    International Nuclear Information System (INIS)

    This paper is aimed at presenting and discussing the methodologies implemented in state-of-the-art models for predicting the physical processes of radionuclide migration through the aquatic environment, including transport due to water currents, diffusion, settling and re-suspension. Models are briefly described, model parameter values reviewed and values recommended. The different modelling approaches are briefly classified and the advantages and disadvantages of the various model approaches and methodologies are assessed.

  18. INTERPRETATION OF COPPER AND ZINC CONTAMINATION IN THE AQUATIC ENVIRONMENT OF PENINSULAR MALAYSIA WITH SPECIAL REFERENCE TO A POLLUTED RIVER, SEPANG RIVER

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Three different aquatic ecosystems(an urban pond,Kelana Jays Pond;a polluted river,Sepang River;and the intertidal and offshore areas of the west coast of Peninsular Malaysia)with different sets of ecological backgrounds and human activities were reviewed and assessed for the levels of Cu and Zn contamination with special reference to those found in polluted sediments collected from the Sepang River.The discussion on the contamination levels of Cu and Zn in the aquatic environment of Peninsular Malaysia was based on a comparison of the metal contamination of 4 kinds of aquatic environments.The comparison of 4 different areas was based on①total concentrations of 2 metals;②the concentrations and percentages of the nonresistant(EFLE,acid-reducible and oxidisable-organic)and resistant geochemical fractions;and③correlation coefficients(R-values)based on data of 4 areas separately and a combination of 4 areas.The Sepang River recorded nonresistant fractions of 63.1%for Zn and 55.8%for Cu in addition toslightly lower metal concentrations when compared to those(60%-70%)reported before the shutting down of the piggery activities in that area.These nonresistant metal percentages(55%-63%)indicated that the metal concentrations were still dominated by anthropogenic sources since nonresistant fraction of metals were mostly contributed by anthropogenic sources.The positive results from the four different aquatic environments assessed here provided strong evidence to show that Malaysia's aquatic environment had received anthropogenic Cu and Zn.The present study also showed that thepercentage of the nonresistant fraction and the R-values based on correlation analysis of Cu and Zn could be used as indicators of Cu and Zn pollution in the Malaysian aquatic ecosystem.Based on the present data,the correlation coefficients(R-values)are potential indicators of EFLE Cu and acid-reducible Cu of the sediments.The use of R-values as indicators of metal pollution is suggested and it is

  19. The fate of EDTA and DTPA in aquatic environments receiving waste water from two pulp and paper mills

    Energy Technology Data Exchange (ETDEWEB)

    Remberger, M.; Svenson, Anders

    1997-10-01

    To evaluate the fate of the complexing agents in receiving waters, two basic questions have been addressed: (i) are EDTA and DTPA found in the aquatic environment after discharge into receiving waters and (ii) are they photolytically converted. Two mills, one pulp mill localized at a fresh water lake and one pulp and paper mill at a brackish water were investigated, both mills using bleaching technologies with EDTA and DTPA as complexing agents. Samples were collected at the discharge point and along a gradient in the receiving waters at two occasions: summer at solstice and winter with low light intensity. Samples were taken from surface water, an intermediate depth, and bottom water. A new analytical method was applied, which made it possible to quantify the analytes at sub-{mu}g/l level. The complexing agents EDTA and DTPA and their primary degradation products were detected in the effluent and the receiving waters in the vicinity of the mills. DTPA and the degradation products could be detected a few kilometers from the effluent point while EDTA could be detected in more remote locations at fairly constant concentrations. The absorption of light in the sun spectrum in the water columns of the receiving waters was studied at different localities and during summer and winter conditions. The theoretical photochemical half-life of the ferric complex of EDTA in the surface layer of a central Swedish lake was confirmed. Analysis of EDTA in samples of receiving waters after photolytic treatment showed however, that a large portion of the complexing agent was unaffected by the treatment, indicating that most of the EDTA was complexed with other metals. EDTA in brackish water samples was unaffected by the photolytic treatment upon addition of excess ferric ions, except in winter close to the discharge point. The ease by which the ferric complexes are photochemically converted in ideal conditions seems to be hampered in receiving waters. 42 refs, 16 figs, 2 tabs

  20. Construction of a self- luminescent cyanobacterial bioreporter that detects a broad range of bioavailable heavy metals in aquatic environments

    Directory of Open Access Journals (Sweden)

    Keila eMartin-Betancor

    2015-03-01

    Full Text Available A self-luminescent bioreporter strain of the unicellular cyanobacterium Synechococcus sp. PCC 7942 was constructed by fusing the promoter region of the smt locus (encoding the transcriptional repressor SmtB and the metallothionein SmtA to luxCDABE from Photorhabdus luminescens; the sensor smtB gene controlling the expression of smtA was cloned in the same vector. The bioreporter performance was tested with a range of heavy metals and was shown to respond linearly to divalent Zn, Cd, Cu, Co, Hg and monovalent Ag. Chemical modelling was used to link bioreporter response with metal speciation and bioavailability. Limits of Detection (LODs, Maximum Permissive Concentrations (MPCs and dynamic ranges for each metal were calculated in terms of free ion concentrations. The ranges of detection varied from 11 to 72 pM for Hg2+ (the ion to which the bioreporter was most sensitive to 1.54-5.35 µM for Cd2+ with an order of decreasing sensitivity as follows: Hg2+ >> Cu2+ >> Ag+ > Co2+ ≥ Zn2+ > Cd2+. However, the maximum induction factor reached 75-fold in the case of Zn2+ and 56-fold in the case of Cd2+, implying that Zn2+ is the preferred metal in vivo for the SmtB sensor, followed by Cd2+, Ag+ and Cu2+ (around 45-50-fold induction, Hg2+ (30-fold and finally Co2+ (20-fold. The bioreporter performance was tested in real environmental samples with different water matrix complexity artificially contaminated with increasing concentrations of Zn, Cd, Ag and Cu, confirming its validity as a sensor of free heavy metal cations bioavailability in aquatic environments.

  1. Construction of a self-luminescent cyanobacterial bioreporter that detects a broad range of bioavailable heavy metals in aquatic environments.

    Science.gov (United States)

    Martín-Betancor, Keila; Rodea-Palomares, Ismael; Muñoz-Martín, M A; Leganés, Francisco; Fernández-Piñas, Francisca

    2015-01-01

    A self-luminescent bioreporter strain of the unicellular cyanobacterium Synechococcus sp. PCC 7942 was constructed by fusing the promoter region of the smt locus (encoding the transcriptional repressor SmtB and the metallothionein SmtA) to luxCDABE from Photorhabdus luminescens; the sensor smtB gene controlling the expression of smtA was cloned in the same vector. The bioreporter performance was tested with a range of heavy metals and was shown to respond linearly to divalent Zn, Cd, Cu, Co, Hg, and monovalent Ag. Chemical modeling was used to link bioreporter response with metal speciation and bioavailability. Limits of Detection (LODs), Maximum Permissive Concentrations (MPCs) and dynamic ranges for each metal were calculated in terms of free ion concentrations. The ranges of detection varied from 11 to 72 pM for Hg(2+) (the ion to which the bioreporter was most sensitive) to 1.54-5.35 μM for Cd(2+) with an order of decreasing sensitivity as follows: Hg(2+) > Cu(2+) > Ag(+) > Co(2+) ≥ Zn(2+) > Cd(2+). However, the maximum induction factor reached 75-fold in the case of Zn(2+) and 56-fold in the case of Cd(2+), implying that Zn(2+) is the preferred metal in vivo for the SmtB sensor, followed by Cd(2+), Ag(+) and Cu(2+) (around 45-50-fold induction), Hg(2+) (30-fold) and finally Co(2+) (20-fold). The bioreporter performance was tested in real environmental samples with different water matrix complexity artificially contaminated with increasing concentrations of Zn, Cd, Ag, and Cu, confirming its validity as a sensor of free heavy metal cations bioavailability in aquatic environments. PMID:25806029

  2. Use of graphene as protection film in biological environments

    Science.gov (United States)

    Zhang, Weixia; Lee, Sudarat; McNear, Kelly L.; Chung, Ting Fung; Lee, Seunghyun; Lee, Kyunghoon; Crist, Scott A.; Ratliff, Timothy L.; Zhong, Zhaohui; Chen, Yong P.; Yang, Chen

    2014-02-01

    Corrosion of metal in biomedical devices could cause serious health problems to patients. Currently ceramics coating materials used in metal implants can reduce corrosion to some extent with limitations. Here we proposed graphene as a biocompatible protective film for metal potentially for biomedical application. We confirmed graphene effectively inhibits Cu surface from corrosion in different biological aqueous environments. Results from cell viability tests suggested that graphene greatly eliminates the toxicity of Cu by inhibiting corrosion and reducing the concentration of Cu2+ ions produced. We demonstrated that additional thiol derivatives assembled on graphene coated Cu surface can prominently enhance durability of sole graphene protection limited by the defects in graphene film. We also demonstrated that graphene coating reduced the immune response to metal in a clinical setting for the first time through the lymphocyte transformation test. Finally, an animal experiment showed the effective protection of graphene to Cu under in vivo condition. Our results open up the potential for using graphene coating to protect metal surface in biomedical application.

  3. Tulane/Xavier University hazardous materials in aquatic environments of the Mississippi River Basin. Annual technical report, January 1--December 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-02

    Tulane and Xavier Universities have singled out the environment as a major strategic focus for research and training for now and beyond the year 2000. In 1989, the Tulane/Xavier Center for Bioenvironmental Research (CBR) was established as the umbrella organization which coordinates environmental research at both universities. In December, 1992, the Tulane/Xavier CBR was awarded a five year grant to study pollution in the Mississippi River system. The Hazardous Materials in Aquatic Environments of the Mississippi River Basin project is a broad research and education program aimed at elucidating the nature and magnitude of toxic materials that contaminate aquatic environments of the Mississippi River Basin. Studies include defining the complex interactions that occur during the transport of contaminants, the actual and potential impact on ecological systems and health, and the mechanisms through which these impacts might be remediated. The Mississippi River Basin represents a model system for analyzing and solving contamination problems that are found in aquatic systems world-wide. Summaries which describe objectives, goals, and accomplishments are included on ten collaborative cluster projects, two education projects, and six initiation projects. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  4. Antibiotic resistance in bacteria isolated from freshwater aquacultures and prediction of the persistence and toxicity of antimicrobials in the aquatic environment.

    Science.gov (United States)

    Lim, Seung J; Jang, Eunhee; Lee, Sang-Hun; Yoo, Byeong-Hak; Kim, Sun-Kyoung; Kim, Tak-Hyun

    2013-01-01

    The occurrence of antibiotic-resistant bacteria isolated from freshwater aquaculture effluents was investigated. The bacterial strains were collected from four different freshwater aquaculture effluents (catfish, trout, eel, and loach). Based on sequence of 16S rRNA, a total of 20 bacterial strains was isolated and one half of the isolated bacteria were Aeromonas sp. The antimicrobial sensitivity test was performed using the disc diffusion method. Individual antibiotic-resistant bacteria to antimicrobials were 41.7% and multiple antibiotic resistant bacteria were 58.3%. The disinfection of antibiotic-resistant bacteria by electron beam (E-beam) irradiation was carried out using an electron accelerator. Antibiotic-resistant bacteria were effectively disinfected by E-beam irradiation. The isolated bacteria were completely disinfected at a dose of less than 2 kGy. The persistence and toxicity of each antimicrobial in the aquatic environment was estimated due to the human health and ecosystems. In order to estimate the persistence and toxicity of antimicrobials in the aquatic environment, two quantitative structure activity relationship (QSAR) models were used. The persistence and toxicity of each antimicrobial were influenced on its hydrophobicity. In addition, QSAR models showed that isoelectric point and hydrogen bonding acceptor are key parameters to estimate the persistence and toxicity of antimicrobials in the aquatic environment. PMID:23452215

  5. A global review and evaluation on the derivation and application of sediment quality criteria to protect aquatic ecosystem and humanhealth

    OpenAIRE

    Chan, Chun-tat.; 陳俊達.

    2012-01-01

    Sediment Quality Guidelines (SQGs) serve as scientific benchmarks, or reference points of chemical contaminants levels for evaluating the possibility of occurrence of adverse biological responses in the aquatic environment. SQGs are important because the quality of sediment has significant influences on the health of aquatic organisms, and the use of SQGs is a critical means to protect and manage various aquatic ecosystems. In this study, nine conventional derivation methods are described an...

  6. Assessing and Managing the Current and Future Pest Risk from Water Hyacinth, (Eichhornia crassipes), an Invasive Aquatic Plant Threatening the Environment and Water Security.

    Science.gov (United States)

    Kriticos, Darren J; Brunel, Sarah

    2016-01-01

    Understanding and managing the biological invasion threats posed by aquatic plants under current and future climates is a growing challenge for biosecurity and land management agencies worldwide. Eichhornia crassipes is one of the world's worst aquatic weeds. Presently, it threatens aquatic ecosystems, and hinders the management and delivery of freshwater services in both developed and developing parts of the world. A niche model was fitted using CLIMEX, to estimate the potential distribution of E. crassipes under historical and future climate scenarios. Under two future greenhouse gas emission scenarios for 2080 simulated with three Global Climate Models, the area with a favourable temperature regime appears set to shift polewards. The greatest potential for future range expansion lies in Europe. Elsewhere in the northern hemisphere temperature gradients are too steep for significant geographical range expansion under the climate scenarios explored here. In the Southern Hemisphere, the southern range boundary for E. crassipes is set to expand southwards in Argentina, Australia and New Zealand; under current climate conditions it is already able to invade the southern limits of Africa. The opportunity exists to prevent its spread into the islands of Tasmania in Australia and the South Island of New Zealand, both of which depend upon hydroelectric facilities that would be threatened by the presence of E. crassipes. In Europe, efforts to slow or stop the spread of E. crassipes will face the challenge of limited internal biosecurity capacity. The modelling technique demonstrated here is the first application of niche modelling for an aquatic weed under historical and projected future climates. It provides biosecurity agencies with a spatial tool to foresee and manage the emerging invasion threats in a manner that can be included in the international standard for pest risk assessments. It should also support more detailed local and regional management. PMID:27513336

  7. Behavior of nanoceria in biologically-relevant environments

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Amit; Das, Soumen; Munusamy, Prabhakaran; Self, William; Baer, Donald R.; Sayle, Dean C.; Seal, Sudipta

    2014-09-08

    Cerium oxide nanoparticles (CNPs) have gained a considerable attention in biological research due to their anti-oxidant like behaviour and regenerative nature. The current literature on CNPs reports many successful attempts on harnessing the beneficial therapeutic properties in biology. However studies have also shown toxicity effect with some types of CNPs. This review discusses issues associated with the behaviours of CNPs in biological systems and identifies key knowledge gaps. We explore how salient physicochemical properties (size, surface chemistry, surface stabilizers) contribute to the potential positive and negative aspects of nanoceria in biological systems. Based on variations of results reported in the literature, important issues need to be addressed. Are we really studying the same particles with slight variations in size and physicochemical properties or do the particles being examined have fundamentally different behaviours? Are the variations observed in the result of differences in the initial properties of the particles or the results of downstream effects that emerge as the particles are prepared for specific studies and they interact with biological or other environmental moieties? How should particles be appropriately prepared for relevant environmental/toxicology/safety studies? It is useful to recognize that nanoparticles encompass some of the same complexities and variability associated with biological components

  8. Inventory of Engineered Nanoparticle-Containing Consumer Products Available in the Singapore Retail Market and Likelihood of Release into the Aquatic Environment

    Science.gov (United States)

    Zhang, Yuanyuan; Leu, Yu-Rui; Aitken, Robert J.; Riediker, Michael

    2015-01-01

    Consumer products containing engineered nanoparticles (ENP) are already entering the marketplace. This leads, inter alia, to questions about the potential for release of ENP into the environment from commercial products. We have inventoried the prevalence of ENP-containing consumer products in the Singapore market by carrying out onsite assessments of products sold in all major chains of retail and cosmetic stores. We have assessed their usage patterns and estimated release factors and emission quantities to obtain a better understanding of the quantities of ENP that are released into which compartments of the aquatic environment in Singapore. Products investigated were assessed for their likelihood to contain ENP based on the declaration of ENP by producers, feature descriptions, and the information on particle size from the literature. Among the 1,432 products investigated, 138 were “confirmed” and 293 were “likely” to contain ENP. Product categories included sunscreens, cosmetics, health and fitness, automotive, food, home and garden, clothing and footwear, and eyeglass/lens coatings. Among the 27 different types of nanomaterials identified, SiO2 was predominant, followed by TiO2 and ZnO, Carbon Black, Ag, and Au. The amounts of ENP released into the aquatic system, which was estimated on the basis of typical product use, ENP concentration in the product, daily use quantity, release factor, and market share, were in the range of several hundred tons per year. As these quantities are likely to increase, it will be important to further study the fate of ENP that reach the aquatic environment in Singapore. PMID:26213957

  9. Quinolone co-resistance in ESBL- or AmpC-producing Escherichia coli from an Indian urban aquatic environment and their public health implications.

    Science.gov (United States)

    Bajaj, Priyanka; Kanaujia, Pawan Kumar; Singh, Nambram Somendro; Sharma, Shalu; Kumar, Shakti; Virdi, Jugsharan Singh

    2016-01-01

    Quinolone and β-lactam antibiotics constitute major mainstay of treatment against infections caused by pathogenic Escherichia coli. Presence of E. coli strains expressing co-resistance to both these antibiotic classes in urban aquatic environments which are consistently being used for various anthropogenic activities represents a serious public health concern. From a heterogeneous collection of 61 E. coli strains isolated from the river Yamuna traversing through the National Capital Territory of Delhi (India), those harboring blaCTX-M-15 (n = 10) or blaCMY-42 (n = 2) were investigated for co-resistance to quinolones and the molecular mechanisms thereof. Resistance was primarily attributed to amino acid substitutions in the quinolone resistance-determining regions (QRDRs) of GyrA (S83L ± D87N) and ParC (S80I ± E84K). One of the E. coli strains, viz., IPE, also carried substitutions in GyrB and ParE at positions Ser492→Asn and Ser458→Ala, respectively. The phenotypically susceptible strains nevertheless carried plasmid-mediated quinolone resistance (PMQR) gene, viz., qnrS, which showed co-transfer to the recipient quinolone-sensitive E. coli J53 along with the genes encoding β-lactamases and led to increase in minimal inhibitory concentrations of quinolone antibiotics. To the best of our knowledge, this represents first report of molecular characterization of quinolone co-resistance in E. coli harboring genes for ESBLs or AmpC β-lactamases from a natural aquatic environment of India. The study warrants true appreciation of the potential of urban aquatic environments in the emergence and spread of multi-drug resistance and underscores the need to characterize resistance genetic elements vis-à-vis their public health implications, irrespective of apparent phenotypic resistance. PMID:26498967

  10. Wetland Biomass Production: emergent aquatic management options and evaluations. A final subcontract report. [Includes a bibliography containing 686 references on Typha from biological abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Pratt, D.C.; Dubbe, D.R.; Garver, E.G.; Linton, P.J.

    1984-07-01

    The high yield potential and attractive chemical composition of Typha make it a particularly viable energy crop. The Minnesota research effort has demonstrated that total annual biomass yields equivalent to 30 dry tonnes/ha (13 tons/acre) are possible in planted stands. This compares with yields of total plant material between 9 and 16 dry tonnes/ha (4 to 7 tons/acre) in a typical Minnesota corn field. At least 50% of the Typha plant is comprised of a belowground rhizome system containing 40% starch and sugar. This high level of easily fermentable carbohydrate makes rhizomes an attractive feedstock for alcohol production. The aboveground portion of the plant is largely cellulose, and although it is not easily fermentable, it can be gasified or burned. This report is organized in a manner that focuses on the evaluation of the management options task. Results from stand management research performed at the University of Minnesota during 1982 and 1983 are integrated with findings from an extensive survey of relevant emergent aquatic plant research and utilization. These results and findings are then arranged in sections dealing with key steps and issues that need to be dealt with in the development of a managed emergent aquatic bio-energy system. A brief section evaluating the current status of rhizome harvesting is also included along with an indexed bibliography of the biology, ecology, and utilization of Typha which was completed with support from this SERI subcontract. 686 references, 11 figures, 17 tables.

  11. Gene-environment interaction and biological monitoring of occupational exposures

    International Nuclear Information System (INIS)

    Biological monitoring methods and biological limit values applied in occupational and environmental medicine have been traditionally developed on the assumption that individuals do not differ significantly in their biotransformation capacities. It has become clear, however, that this is not the case, but wide inter-individual differences exist in the metabolism of chemicals. Integration of the data on individual metabolic capacity in biological monitoring studies is therefore anticipated to represent a significant refinement of the currently used methods. We have recently conducted several biological monitoring studies on occupationally exposed subjects, which have included the determination of the workers' genotypes for the metabolic genes of potential importance for a given chemical exposure. The exposure levels have been measured by urine metabolites, adducts in blood macromolecules, and cytogenetic alterations in lymphocytes. Our studies indicate that genetic polymorphisms in metabolic genes may indeed be important modifiers of individual biological monitoring results of, e.g., carbon disulphide and styrene. The information is anticipated to be useful in insuring that the workplace is safe for everyone, including the most sensitive individuals. This knowledge could also be useful to occupational physicians, industrial hygienists, and regulatory bodies in charge of defining acceptable exposure limits for environmental and/or occupational pollutants

  12. Caloric density of aquatic macrophytes in different environments of the Baía river subsystem, upper Paraná river floodplain, Brazil

    OpenAIRE

    Célia de Almeida Lopes; Anna Christina Esper Amaro de Faria; Gislaine Iachstel Manetta; Evanilde Benedito-Cecilio

    2006-01-01

    The aim of this work was to determine the caloric density of leaves, stems and roots of aquatic macrophytes in different environments of the Baía subsystem (Baía river and Fechada and Guaraná lagoons) on the Upper Paraná river floodplain, in addition to identify the variability between ecological groups. Samplings of Eichhornia crassipes, Salvinia spp, Pistia stratiotes, Eichhornia azurea, Polygonum sp, Cyperaceae and Poaceae were carried out in February 2003. Spatial differences in the calor...

  13. Tulane/Xavier Center for Bioenvironmental Research; project: hazardous materials in aquatic environments; subproject: biomarkers and risk assessment in Bayou Trepagnier, LA

    International Nuclear Information System (INIS)

    Tulane and Xavier Universities have singled out the environment as a major strategic focus for research and training for now and beyond the year 2000. the Tulane/Xavier Center for Bioenvironmental Research (CBR) was established in 1989 as the umbrella organization to coordinate environmental research at both universities. CBR projects funded by the DOE under the Hazardous Materials in Aquatic Environments grant are defining the following: (1) the complex interactions that occur during the transport of contaminants through wetlands environments, (2) the actual and potential impact of contaminants on ecological systems and health, (3) the mechanisms and new technologies through which these impacts might be remediated, and (4) new programs aimed at educating and training environmental workers of the future. The subproject described in this report, 'Biomarkers and Risk Assessment in Bayou Trepagnier, LN', is particularly relevant to the US Department of Energy's Environmental Restoration and Waste Management program aimed at solving problems related to hazard monitoring and clean-up prioritization at sites with aquatic pollution problems in the DOE complex

  14. Assessment of background concentrations of organometallic compounds (methylmercury, ethyllead and butyl- and phenyltin) in French aquatic environments.

    Science.gov (United States)

    Cavalheiro, Joana; Sola, Cristina; Baldanza, Julie; Tessier, Emmanuel; Lestremau, François; Botta, Fabrizio; Preud'homme, Hugues; Monperrus, Mathilde; Amouroux, David

    2016-05-01

    The aim of this work is to estimate background concentrations of organometallic compounds, such as tributyltin (TBT), dibutyltin (DBT), monobutyltin (MBT), triphenyltin (TPhT), diphenyltin (DPhT), monophenyltin (MPhT), methylmercury (MeHg), inorganic mercury (iHg) and diethyllead (Et2Pb) in the aquatic environment at the French national scale. Both water and sediment samples were collected all over the country, resulting in 152 water samples and 123 sediment samples collected at 181 sampling points. Three types of surface water bodies were investigated: rivers (140 sites), lakes (19 sites) and coastal water (42 sites), spread along the 11 French river basins. The choice of sites was made on the basis of previous investigation results and the following target criteria: reference, urban sites, agricultural and industrial areas. The analytical method was properly validated for both matrices prior to analysis, resulting in low limits of quantification (LOQ), good precision and linearity in agreement with the Water Framework Directive demands. The results were first evaluated as a function of their river basins, type of surrounding pressure and water bodies. Later, background concentrations at the French national scale were established for both water and sediment matrices, as well as their threshold, i.e., the concentration that distinguishes background from anomalies or contaminations. Background concentrations in water are ranging between <0.04-0.14 ng Hg. L(-1) for MeHg, <0.14-2.10 ng Hg. L(-1) for iHg, <1.0-8.43 ng Pb. L(-1) for Et2Pb and 0.49-151 ng Sn. L(-1), <0.08-3.04 ng Sn. L(-1) and <0.08-0.25 ng Sn. L(-1) for MBT, DBT and TBT, respectively. For sediments, background concentrations were set as <0.09-1.11 ng Hg. g(-1) for MeHg, <0.06-24.3 ng Pb. g(-1) for Et2Pb and <1.4-13.4 ng Sn. g(-1), <0.82-8.54 ng Sn. g(-1), <0.25-1.16 ng Sn. g(-1) and <0.08-0.61 ng Sn. g(-1) for MBT, DBT, TBT and DPhT, respectively. TBT occurs in higher concentrations

  15. Relationship between P and the most reactive fraction of Fe(III) oxyhydroxide in various aquatic and sedimentary environments

    Science.gov (United States)

    Anschutz, Pierre

    2014-05-01

    Phosphorus can experience a series of biogeochemical pathways. Primary P has an igneous origin and occurs mostly as apatite in bedrocks. Once P is dissolved as phosphate ion, it can incorporate organic matter or become adsorbed onto inorganic particles. The liberation of P from organic matter through bacterial respiration produces a subsequent flux back to the biota or a storage in Fe and Al oxyhydroxides, or in authigenic or biogenic phosphate minerals. The adsorption of phosphate on Fe- and Al-oxide and oxyhydroxide has been extensively studied in soil science because phosphorus is a limiting nutrient in terrestrial ecosystems, and sorptive removal of natural or fertilizer phosphorus impacts the production level of crops and forests. Fe(III) oxides/oxyhydroxides are subject to reductive dissolution, and consequently redox conditions play an important role in soil P-bioavailability. The main process of phosphorus removal from the aquatic systems is burial with sediments. Exchange between sediment and overlying water takes place through benthic biogeochemical processes, including organic-P mineralization, redox-driven Fe-P cycling, and benthic phosphorus efflux from sediments. A portion of the pore-water phosphate derived from organic matter mineralization may be adsorbed onto detrital or authigenic iron oxyhydroxides in the oxidized zone of the sediment. Once advected in the reduced zone of sediments through burial or bioturbation, the most reducible fraction of Fe(III) phase can be reduced and solubilized, leading to a release of phosphate. Eventually, P can be buried over long period as relict organic-P, P associated with refractory iron oxides, and apatite. Therefore, Fe-bound P is often the initial sink of P supplied by organic matter, but not the major final sink. Several techniques have been developed to extract P bound to Fe(III) phases. The citrate-dithionite buffered (CDB) solution is one of the most often used solution to measure Fe(III)-bound P. CDB

  16. Comparative biological tests in aquatic systems to determine the adverse effect of combinations of pollutants with several components

    International Nuclear Information System (INIS)

    In tests with luminous bacteria, algae and daphnes as representatives of different trophic stages, the combination effect of heavy metals (Cd, Cr) and organic pollutants (p-chloroaniline, 1,2,3-trichlorobenzene, Na3-NTA) in aquatic ecosystems is exemplarily tested with subsequent comparison of the results with models of the combination effect. The author differentiates between the principles of action ''similar joint action'' = ''concentration addition'', ''independent action'' = ''response addition'' and ''synergistic action'' and employs mathematical models juxtaposing a ''simple similar action'', and ''independent action'' to a ''complex similar action'' and ''dependent action'', respectively, as well as the ''toxic unit model'', which translates the concentration of a substance into the corresponding toxicological efficacy. Most, but not all of the investigated binary mixtures of substances exhibited additive effects, but some of the combination effects depended on the proportions in the mixture. Further combination effects found were less-than-additive, more-than-additive (Cd/Cr) and antagonistic ones. (uWA)

  17. Remaining Sites Verification Package for the 100-F-52, 146-FR Radioecology and Aquatic Biology Laboratory Soil. Attachment to Waste Site Reclassification Form 2008-022

    International Nuclear Information System (INIS)

    The 100-F-52 waste site consisted of the soil under and around the former 146-FR Radioecology and Aquatic Biology Laboratory. The laboratory was used for studies of the effects of pre-reactor and post-reactor process water on fish eggs, young fish, and other small river creatures of interest. In accordance with this evaluation, the confirmatory sampling results support a reclassification of this site to No Action. The current site conditions achieve the remedial action objectives and the corresponding remedial action goals established in the Remaining Sites ROD. The results of confirmatory sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River

  18. Viscosity and not biological mechanisms often controls the effects of temperature on ciliary activity and swimming velocity of small aquatic organisms

    DEFF Research Database (Denmark)

    Larsen, Poul Scheel; Riisgård, H. U.

    2009-01-01

    A number of studies have shown that temperature-dependent viscosity of the ambient water controls or strongly affects bio-mechanical activity such as beat frequency of water-pumping cilia in mussels and ascidians, swimming velocity of sperm cells, ciliates and small (micro- and meso-scale) aquatic...... organisms using cilia or small appendages for propulsion. Here we summarize results from the literature and from own studies on bio-mechanical activities in response to changing temperature or manipulated viscosity at constant temperature, both having the same change in kinematic viscosity. The survey is...... used to assess to what extent the response is purely physical/mechanical or biological. We argue that a power-law dependence of bio-mechanical activity (a) on kinematic viscosity (ν), i.e. a ~ ν^−m, should be applied to available data. Based on a general close matching of the response data to power-law...

  19. Remaining Sites Verification Package for the 100-F-52, 146-FR Radioecology and Aquatic Biology Laboratory Soil, Waste Site Reclassification Form 2008-022

    Energy Technology Data Exchange (ETDEWEB)

    J. M. Capron

    2008-06-27

    The 100-F-52 waste site consisted of the soil under and around the former 146-FR Radioecology and Aquatic Biology Laboratory. The laboratory was used for studies of the effects of pre-reactor and post-reactor process water on fish eggs, young fish, and other small river creatures of interest. In accordance with this evaluation, the confirmatory sampling results support a reclassification of this site to No Action. The current site conditions achieve the remedial action objectives and the corresponding remedial action goals established in the Remaining Sites ROD. The results of confirmatory sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.

  20. A review of research on common biological agents and their impact on environment

    International Nuclear Information System (INIS)

    Biological agents are unique class of microorganisms which can be used to produce the disease in large populations of humans, animals and plants. If used for hostile purposes, any disease-causing microorganism could be considered a weapon. The use of biological agents is not a new concept and history is replete with examples of biological weapon use. Before the twenty century, biological warfare took on three main forms by deliberate poisoning of food and water with infectious material, use of microorganisms or toxins in some form of weapon system, and use of biologically inoculated fabrics. Four kinds of biological warfare agents are bacteria, viruses, rickettsiae, fungi. These are distinguished by being living organisms, that reproduce within their host victims, who then become contagious with a deadly multiplier effect, bacteria, viruses, or fungi or toxin found in nature can be used to kill or injure people. Biological agents may be used for an isolated assassination, as well as to cause incapacitation or death to thousands. These biological agents represent a dangerous military threat because they are alive, and are therefore unpredictable and uncontrollable once released. The act of bioterrorism can range from a simple hoax to the actual use of biological weapons. Biological agents have the potential to make an environment more dangerous over time. If the environment is contaminated, a long-term threat to the population could be created. This paper discusses common biological agents, their mode of action in living organisms and possible impact on the environment. (author)

  1. A toxicidade em ambientes aquáticos: discussão e métodos de avaliação Toxicity in aquatic environments: discussion and evaluation methods

    Directory of Open Access Journals (Sweden)

    Carla Regina Costa

    2008-01-01

    Full Text Available Aquatic toxicity tests are assays performed with different aquatic organisms of different ecological organization levels. Such tests are a source of information on the toxicity of a given substance or wastewater under controlled conditions, and they complement the physico-chemical analyses. Moreover, they allow one to evaluate the risks resulting from the presence of toxic substances in the environment. Algae, crustaceans, fishes and bacteria are frequently used in toxicity tests. In this work, we will present the main aspects related to the aquatic toxicity tests and a discussion of their applicability will also be presented.

  2. Detection of the macrolide-lincosamide-streptogramin B resistance gene erm(44) and a novel erm(44) variant in staphylococci from aquatic environments.

    Science.gov (United States)

    Wendlandt, Sarah; Heß, Stefanie; Li, Jun; Feßler, Andrea T; Wang, Yang; Kadlec, Kristina; Gallert, Claudia; Schwarz, Stefan

    2015-08-01

    Resistance to macrolides, lincosamides and streptogramin B antibiotics (MLSB) is not restricted to staphylococci from clinical samples but can also be present in staphylococci from the aquatic environment. Two coagulase-negative staphylococci-Staphylococcus xylosus and S. saprophyticus were obtained from sewage and receiving river water samples and were investigated for the genetic basis of inducible MLSB resistance by whole-genome sequencing. Two rRNA methylases encoded by erm(44) and a novel erm(44) variant were identified, which had only 84% amino acid identity. While fragments of phage DNA were found in the vicinity of the erm(44) gene of S. xylosus, no relics of mobile genetic elements were detected in the sequences flanking the erm(44) variant gene in the S. saprophyticus strain. The functionality of the erm genes was confirmed by cloning and transformation experiments. Based on the obtained sequences, specific PCR assays for both erm genes were developed and used to identify erm(44) in another 7 S. xylosus and 17 S. saprophyticus isolates from aquatic environments. PMID:26207047

  3. Distribution, speciation, environmental risk, and source identification of heavy metals in surface sediments from the karst aquatic environment of the Lijiang River, Southwest China.

    Science.gov (United States)

    Xu, Daoquan; Wang, Yinghui; Zhang, Ruijie; Guo, Jing; Zhang, Wei; Yu, Kefu

    2016-05-01

    The distribution and speciation of several heavy metals, i.e., As, Cd, Cr, Cu, Hg, Pb, and Zn, in surface sediments from the karst aquatic environment of the Lijiang River, Southwest China, were studied comparatively. The mean contents of Cd, Cu, Hg, Pb, and Zn were 1.72, 38.07, 0.18, 51.54, and 142.16 mg/kg, respectively, which were about 1.5-6 times higher than their corresponding regional sediment background values. Metal speciation obtained by the optimized BCR protocol highlighted the bioavailable threats of Cd, Cu, and Zn, which were highly associated with the exchangeable fraction (the labile phase). Hierarchical cluster analysis indicated that in sediments, As and Cr were mainly derived from natural and industrial sources, whereas fertilizer application might lead to the elevated level of Cd. Besides, Cu, Hg, Pb, and Zn were related to traffic activities. The effects-based sediment quality guidelines (SQGs) showed that Hg, Pb, and Zn could pose occasional adverse effects on sediment-dwelling organisms. However, based on the potential ecological risk assessment (PER) and risk assessment code (RAC), Cd was the most outstanding pollutant and posed the highest ecological hazard and bioavailable risk among the selected metals. Moreover, the metal partitioning between water and sediments was quantified through the calculation of the pseudo-partitioning coefficient (K P), and result implied that the sediments in this karst aquatic environment cannot be used as stable repositories for the metal pollutants. PMID:26832870

  4. Environment. Biological processing of wastes; Environnement. Traitement biologique des dechets

    Energy Technology Data Exchange (ETDEWEB)

    Gourdon, R. [Institut National des Sciences Appliquees, INSA, Lab. d' Analyse Environnementale des Procedes et des Systemes Industriels, 69 - Villeurbanne (France)

    2001-01-01

    The main principle of the biological processing is the utilization of microbial activities by a control stimulation in order to decrease the wastes harmful effects, or by an energetic valorization. This paper deals with the solid wastes or the sludges. After a short presentation of the concerned wastes, their metabolism and their consequences, the author details two treatments: the composting (aerobic) and the methanization (anaerobic). The last part is devoted to the alcoholic fermentation and the industrial wastes (non agricultural) processing. (A.L.B.)

  5. A supplement to "Methods for collection and analysis of aquatic biological and microbiological samples" (U.S. Geological Survey Techniques of Water-Resources Investigations, Book 5, Chapter A4)

    Science.gov (United States)

    1979-01-01

    The manual contains methods used by the U.S. Geological Survey to collect, preserve, and analyze waters to determine their biological and microbiological properties. It supplements ' Methods for Collection and Analysis of Aquatic Biological and Microbiological Samples ' (TWRI, Book 5, Chapter A4, 1977, edited by P. E. Greeson, T. A. Ehlke, G. A. Irwin, B. W. Lium, and K. V. Slack). Included are 5 new methods, a new section of selected taxonomic references for Ostracoda, and 6 revised methods.

  6. Turkish secondary education students' perceptions of their classroom learning environment and their attitude towards Biology

    OpenAIRE

    Telli, S.; Cakiroglu, J.; den Brok, P.

    2006-01-01

    The domain of learning environments research has produced many promising findings, leading to an enhancement of the teaching and learning process in many countries. However, there have been a limited number of studies in this field in Turkey. For that reason, the purpose of the present study was to examine Turkish high school students’ perceptions of their classroom environment in biology and to investigate relationships between these perceptions and students’ attitudes toward biology. Second...

  7. Student Perceptions of the Cell Biology Laboratory Learning Environment in Four Undergraduate Science Courses in Spain

    Science.gov (United States)

    De Juan, Joaquin; Pérez-Cañaveras, Rosa M.; Segovia, Yolanda; Girela, Jose Luis; Martínez-Ruiz, Noemi; Romero-Rameta, Alejandro; Gómez-Torres, Maria José; Vizcaya-Moreno, M. Flores

    2016-01-01

    Cell biology is an academic discipline that organises and coordinates the learning of the structure, function and molecular composition of cells in some undergraduate biomedical programs. Besides course content and teaching methodologies, the laboratory environment is considered a key element in the teaching of and learning of cell biology. The…

  8. A rational approach to selecting and ranking some pharmaceuticals of concern for the aquatic environment and their relative importance compared with other chemicals.

    Science.gov (United States)

    Donnachie, Rachel L; Johnson, Andrew C; Sumpter, John P

    2016-04-01

    Aquatic organisms can be exposed to thousands of chemicals discharged by the human population. Many of these chemicals are considered disruptive to aquatic wildlife, and the literature on the impacts of these chemicals grows daily. However, because time and resources are not infinite, research must focus on the chemicals that represent the greatest threat. One group of chemicals of increasing concern is pharmaceuticals, for which the primary challenge is to identify which represent the greatest threat. In the present study, a list of 12 pharmaceuticals was compiled based on scoring the prevalence of different compounds from previous prioritization reviews. These included rankings based on prescription data, environmental concentrations, predicted environmental concentration/predicted no-effect concentration (PEC/PNEC) ratios, persistency/bioaccumulation/(eco)toxicity (PBT), and fish plasma model approaches. The most frequently cited were diclofenac, paracetamol, ibuprofen, carbamazepine, naproxen, atenolol, ethinyl estradiol, aspirin, fluoxetine, propranolol, metoprolol, and sulfamethoxazole. For each pharmaceutical, literature on effect concentrations was compiled and compared with river concentrations in the United Kingdom. The pharmaceuticals were ranked by degree of difference between the median effect and median river concentrations. Ethinyl estradiol was ranked as the highest concern, followed by fluoxetine, propranolol, and paracetamol. The relative risk of these pharmaceuticals was compared with those of metals and some persistent organic pollutants. Pharmaceuticals appear to be less of a threat to aquatic organisms than some metals (Cu, Al, Zn) and triclosan, using this ranking approach. Environ Toxicol Chem 2016;35:1021-1027. © 2015 The Authors. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc. on behalf of SETAC. PMID:26184376

  9. Biological Aspects of Disposal of Radioactive Wastes in Marine Environments

    International Nuclear Information System (INIS)

    Disposal of radioactive wastes in marine waters allows for an accumulation of radioactivity by marine life. Such an accumulation by seafood organisms might affect their utilization or availability. Laboratory studies of accumulation of important radionuclides present in different wastes by marine plankton, benthic invertebrates and various species of marine fish and of the biological effects of accumulated radioactivity on these forms are being conducted at Beaufort, North Carolina, as a co-operative activity of the US Atomic Energy Commission and the US Bureau of Commercial Fisheries. These investigations help provide essential information for the formulation of waste disposal practices and the safe operation of nuclear-powered ships in coastal waters. They are useful also in the development of monitoring programmes designed to detect and evaluate hazards from accidental pollution of inshore waters. (author)

  10. Hazardous materials in aquatic environments of the Mississippi River Basin. Quarterly project status report, 1 April--30 June 1994

    Energy Technology Data Exchange (ETDEWEB)

    1994-08-01

    This report contains a cluster of twenty separate project reports concerning the fate, environmental transport, and toxicity of hazardous wastes in the Mississippi River Basin. Some of topics investigated involve: biological uptake and metabolism; heavy metal immobilization; biological indicators; toxicity; and mathematical models.

  11. Arsenic speciation in biological environmental samples of aquatic ecosystems by using HPLC-ICP-MS; Speciation von Arsen in biologischen Umweltproben aus aquatischen Oekosystemen mittels HPLC-ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Falk, K.

    1999-09-01

    The physicochemical forms of arsenic (arsenic species) which are present in the environment vary significantly with respect to toxicity, bioavailability, stability and transport behaviour. Therefore, it is necessary for an assessment of the toxic potential to humans and the environment to investigate not only the total arsenic concentrations but also to differentiate the single species. By that the knowledge about ecological correlations and pathways will be increased. The present thesis reports the results of a Ph.D. study on the development and optimisation of analytical methods for arsenic speciation and their application to biological samples from different aquatic ecosystems in Germany. The method development included separation of 12 naturally occurring arsenic species by high-performance liquid chromatography (HPLC) followed by an arsenic selective detection by inductively coupled plasma-mass spectrometry (ICP-MS). The arsenic species As (III), As (V), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), arsenobetaine (AB), arsenocholine (AC), trimethylarsine oxid (TMAO) and tetramethylarsonium (Tetra) were separated with ion-exchange chromatography, whereas reversed-phase chromatography was used for the separation of four arsenosugars. Because of the partly low arsenic concentration in biological samples a very good detection power was required. Therefore, an HPLC-ICP-MS system was tested with different nebulizers. Using the high efficiency nebulizer HHPN (Hydraulic High Pressure Nebulizer), detection limits in the low pg-range could be achieved. The developed analytical methods were applied to arsenic speciation in four marine matrices, which are representative of different trophic levels in the food chain. All samples originated from an ecosystem in the North Sea.

  12. Development of naturally occurring siliceous material for the preferential removal of thorium from U-Th aquatic environment

    International Nuclear Information System (INIS)

    During this work laboratory simulated experiments were conducted to study the preferential removal of thorium by using siliceous material having particle size of about 2000 μm. Siliceous material was prepared by decomposing the organic layer on soil particles by giving treatment with HNO3 and H2O2. Experimental solutions were generated by spiking the tap water with Th(NO3)4 and UO2(NO3)2. Highly particle reactive nature of thorium was exploited for the separation of Th from aquatic stream containing U/Th. The Kd value of Th(IV) ions is 106 which is two order of magnitude higher than uranium (IV and VI). Experimental results show that 90% of the spiked Th is in association with silicious material whereas uranium is only 20-30%. (author)

  13. Biología reproductiva de la serpiente semiacuática Liophis semiaureus (Serpentes, Colubridae en el nordeste de Argentina Reproductive biology of the semi-aquatic snake Liophis semiaureus (Serpentes, Colubridae in the north-east of Argentina

    Directory of Open Access Journals (Sweden)

    SOLEDAD M LÓPEZ

    2009-06-01

    Full Text Available Las serpientes tienen una notable flexibilidad y diversidad en sus tácticas reproductivas, a pesar de ello, los estudios acerca de la biología reproductiva de especies sudamericanas en zonas subtropicales-templadas son escasos. Se analizó la biología reproductiva de Liophis semiaureus en el nordeste de Argentina, incluyendo la madurez y dimorfismo sexual, fecundidad y ciclo reproductivo. Las hembras maduras fueron significativamente más largas, presentaron mayor peso corporal y alcanzaron la madurez sexual a una longitud mayor que los machos. Los machos tuvieron colas más largas que las hembras. El ciclo reproductivo fue estacional con mayor actividad en los períodos templados del año aunque previos a la época de inundaciones. Liophis semiaureus invirtió más energía en la reproducción que en el crecimiento, lo que posibilita que comiencen a reproducirse con tamaños más pequeños con respecto a otras poblaciones, sin retrasar su reproducción hasta alcanzar mayores tamaños. Esta puede ser una estrategia ventajosa en climas estacionales. Las características reproductivas y de dimorfismo sexual en L. semiaureus se encontrarían influenciadas por aspectos filogenéticos, geográficos y ecológicos, lo que determina que la especie responda de manera general al patrón reproductivo del grupo taxonómico pero con particularidades propias determinadas por los factores geográficos y los requerimientos ecológicos.Snakes in subtropical warm zones have a wide flexibility and diversity in your reproductive tactics. In spite of it, the studies in South America about that are scanty yet. We analyzed sexual dimorphism, sexual maturity, fecundity and reproductive cycle of a semi-aquatic snake, Liophis semiaureus, in north-east of Argentina. Females were significantly longer and heavier than the males. Females reach sexual maturity with longer snout-vent length than the males. Males had longer tails than the females. The reproductive cycle was

  14. Environmental and radiological safety studies. Interaction of 238PuO2 heat sources with terrestrial and aquatic environments. Progress report, July 1-September 30, 1980

    International Nuclear Information System (INIS)

    The containers for 238PuO2 heat sources in radioisotope thermoelectric generators are designed with large safety factors to ensure that they will withstand reentry from orbit and impact with the earth and safely contain the nuclear fuel until it is recovered. Existing designs have proved more than adequately safe, but the Space and Terrestrial Division of the Department of Energy Office of Advanced Nuclear Systems and Projects continually seeks more information about the heat sources to improve their safety. The work discussed here includes studies of the effects on the heat source of terrestrial and aquatic environments to obtain data for design of even safer systems. The data obtained in several ongoing experiments are presented; these data tables will be updated quarterly. Discussions of experimental details are minimized and largely repetitive in succeeding reports. Compilations of usable data generated in each experiment are emphasized. These compilations include data from environmental chamber experiments that simulate terrestrial conditions, experiments to measure PuO2 dissolution rates, soil column experiments to measure sorption of plutonium by soils, and several aquatic experiments

  15. Metal release from stainless steel in biological environments: A review.

    Science.gov (United States)

    Hedberg, Yolanda S; Odnevall Wallinder, Inger

    2016-03-01

    Due to its beneficial corrosion resistance, stainless steel is widely used in, e.g., biomedical applications, as surfaces in food contact, and for products intended to come into skin contact. Low levels of metals can be released from the stainless steel surface into solution, even for these highly corrosion resistant alloys. This needs to be considered in risk assessment and management. This review aims to compile the different metal release mechanisms that are relevant for stainless steel when used in different biological settings. These mechanisms include corrosion-induced metal release, dissolution of the surface oxide, friction-induced metal release, and their combinations. The influence of important physicochemical surface properties, different organic species and proteins in solution, and of biofilm formation on corrosion-induced metal release is discussed. Chemical and electrochemical dissolution mechanisms of the surface oxides of stainless steel are presented with a focus on protonation, complexation/ligand-induced dissolution, and reductive dissolution by applying a perspective on surface adsorption of complexing or reducing ligands and proteins. The influence of alloy composition, microstructure, route of manufacture, and surface finish on the metal release process is furthermore discussed as well as the chemical speciation of released metals. Typical metal release patterns are summarized. PMID:26514345

  16. Selected Water- and Sediment-Quality, Aquatic Biology, and Mine-Waste Data from the Ely Copper Mine Superfund Site, Vershire, VT, 1998-2007

    Science.gov (United States)

    Argue, Denise M.; Kiah, Richard G.; Piatak, Nadine M.; Seal, Robert R., II; Hammarstrom, Jane M.; Hathaway, Edward; Coles, James F.

    2008-01-01

    The data contained in this report are a compilation of selected water- and sediment-quality, aquatic biology, and mine-waste data collected at the Ely Copper Mine Superfund site in Vershire, VT, from August 1998 through May 2007. The Ely Copper Mine Superfund site is in eastern, central Vermont (fig. 1) within the Vermont Copper Belt (Hammarstrom and others, 2001). The Ely Copper Mine site was placed on the U.S. Environmental Protection Agency (USEPA) National Priorities List in 2001. Previous investigations conducted at the site documented that the mine is contributing metals and highly acidic waters to local streams (Hammarstrom and others, 2001; Holmes and others, 2002; Piatak and others, 2003, 2004, and 2006). The U.S. Geological Survey (USGS), in cooperation with the USEPA, compiled selected data from previous investigations into uniform datasets that will be used to help characterize the extent of contamination at the mine. The data may be used to determine the magnitude of biological impacts from the contamination and in the development of remediation activities. This report contains analytical data for samples collected from 98 stream locations, 6 pond locations, 21 surface-water seeps, and 29 mine-waste locations. The 98 stream locations are within 3 streams and their tributaries. Ely Brook flows directly through the Ely Copper Mine then into Schoolhouse Brook (fig. 2), which joins the Ompompanoosuc River (fig. 1). The six pond locations are along Ely Brook Tributary 2 (fig. 2). The surface-water seeps and mine-waste locations are near the headwaters of Ely Brook (fig. 2 and fig. 3). The datasets 'Site_Directory' and 'Coordinates' contain specific information about each of the sample locations including stream name, number of meters from the mouth of stream, geographic coordinates, types of samples collected (matrix of sample), and the figure on which the sample location is depicted. Data have been collected at the Ely Copper Mine Superfund site by the

  17. Biological and ecological characteristics of Tamarix L. And its effect on the ecological environment

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Daoyuan(张道元); YIN; Linke(尹林克); PAN; Borong(潘伯荣)

    2002-01-01

    Through studying biological and ecological characteristics of Tarnarix L., we foundwide adaptability to different ecological environment and high endurance of adversity. Whenplanted in the edge of desert and periphery of oasis, Tamarix will act as excellent sand-fixingshrubs, improve ecological environment and play a positive role. However, introducing Tamarixunreasonably will deteriorate the ecological environment and reduce biodiversity and play a nega-tive role. Grasping the biological and ecological characteristics of Tamarix will do much to benefitfurther developing and utilizing of the resources.

  18. [Sources of antibiotics in natural environments and their biological role].

    Science.gov (United States)

    Zabłotni, Agnieszka; Jaworski, Adam

    2014-01-01

    Nowadays antibiotics are broadly used not only for treatment of bacterial infections but also in nonmedical applications. For many years they have been added as livestock and poultry growth supplements, and they are applied similarly in fish farming. In basically unchanged form they may get into the natural environment and remain there for a long time. Excessive use of antibiotics leads to widespread of antibiotic resistance among clinical and environmental bacterial strains. Subinhibitory concentrations of antibiotics, which do not inhibit growth of bacteria, are often found in soil, water or even in the tissue of different organisms. Such low concentrations affect many bacterial genes through changes in their transcription level and increase of the mutation rate, and as a consequence lead to many bacterial adaptations to environmental stresses. There is also evidence that subinhibitory concentrations of antibiotics induce transfer of mobile genetic elements through horizontal gene transfer pathways, and therefore enhance antibiotic resistance, also among environmental strains. The analyzed data suggest the necessity of restriction and regular monitoring of antibiotics, which may be considered as environmental pollutants. PMID:25228513

  19. Biology, Genetics, and Environment: Underlying Factors Influencing Alcohol Metabolism.

    Science.gov (United States)

    Wall, Tamara L; Luczak, Susan E; Hiller-Sturmhöfel, Susanne

    2016-01-01

    Gene variants encoding several of the alcohol-metabolizing enzymes, alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), are among the largest genetic associations with risk for alcohol dependence. Certain genetic variants (i.e., alleles)--particularly the ADH1B*2, ADH1B*3, ADH1C*1, and ALDH2*2 alleles--have been associated with lower rates of alcohol dependence. These alleles may lead to an accumulation of acetaldehyde during alcohol metabolism, which can result in heightened subjective and objective effects. The prevalence of these alleles differs among ethnic groups; ADH1B*2 is found frequently in northeast Asians and occasionally Caucasians, ADH1B*3 is found predominantly in people of African ancestry, ADH1C*1 varies substantially across populations, and ALDH2*2 is found almost exclusively in northeast Asians. Differences in the prevalence of these alleles may account at least in part for ethnic differences in alcohol consumption and alcohol use disorder (AUD). However, these alleles do not act in isolation to influence the risk of AUD. For example, the gene effects of ALDH2*2 and ADH1B*2 seem to interact. Moreover, other factors have been found to influence the extent to which these alleles affect a person's alcohol involvement, including developmental stage, individual characteristics (e.g., ethnicity, antisocial behavior, and behavioral undercontrol), and environmental factors (e.g., culture, religion, family environment, and childhood adversity). PMID:27163368

  20. The plastid genome of Najas flexilis: adaptation to submersed environments is accompanied by the complete loss of the NDH complex in an aquatic angiosperm.

    Directory of Open Access Journals (Sweden)

    Elena L Peredo

    Full Text Available The re-colonization of aquatic habitats by angiosperms has presented a difficult challenge to plants whose long evolutionary history primarily reflects adaptations to terrestrial conditions. Many aquatics must complete vital stages of their life cycle on the water surface by means of floating or emergent leaves and flowers. Only a few species, mainly within the order Alismatales, are able to complete all aspects of their life cycle including pollination, entirely underwater. Water-pollinated Alismatales include seagrasses and water nymphs (Najas, the latter being the only freshwater genus in the family Hydrocharitaceae with subsurface water-pollination. We have determined the complete nucleotide sequence of the plastid genome of Najas flexilis. The plastid genome of N. flexilis is a circular AT-rich DNA molecule of 156 kb, which displays a quadripartite structure with two inverted repeats (IR separating the large single copy (LSC from the small single copy (SSC regions. In N. flexilis, as in other Alismatales, the rps19 and trnH genes are localized in the LSC region instead of within the IR regions as in other monocots. However, the N. flexilis plastid genome presents some anomalous modifications. The size of the SSC region is only one third of that reported for closely related species. The number of genes in the plastid is considerably less. Both features are due to loss of the eleven ndh genes in the Najas flexilis plastid. In angiosperms, the absence of ndh genes has been related mainly to the loss of photosynthetic function in parasitic plants. The ndh genes encode the NAD(PH dehydrogenase complex, believed essential in terrestrial environments, where it increases photosynthetic efficiency in variable light intensities. The modified structure of the N. flexilis plastid genome suggests that adaptation to submersed environments, where light is scarce, has involved the loss of the NDH complex in at least some photosynthetic angiosperms.

  1. The plastid genome of Najas flexilis: adaptation to submersed environments is accompanied by the complete loss of the NDH complex in an aquatic angiosperm.

    Science.gov (United States)

    Peredo, Elena L; King, Ursula M; Les, Donald H

    2013-01-01

    The re-colonization of aquatic habitats by angiosperms has presented a difficult challenge to plants whose long evolutionary history primarily reflects adaptations to terrestrial conditions. Many aquatics must complete vital stages of their life cycle on the water surface by means of floating or emergent leaves and flowers. Only a few species, mainly within the order Alismatales, are able to complete all aspects of their life cycle including pollination, entirely underwater. Water-pollinated Alismatales include seagrasses and water nymphs (Najas), the latter being the only freshwater genus in the family Hydrocharitaceae with subsurface water-pollination. We have determined the complete nucleotide sequence of the plastid genome of Najas flexilis. The plastid genome of N. flexilis is a circular AT-rich DNA molecule of 156 kb, which displays a quadripartite structure with two inverted repeats (IR) separating the large single copy (LSC) from the small single copy (SSC) regions. In N. flexilis, as in other Alismatales, the rps19 and trnH genes are localized in the LSC region instead of within the IR regions as in other monocots. However, the N. flexilis plastid genome presents some anomalous modifications. The size of the SSC region is only one third of that reported for closely related species. The number of genes in the plastid is considerably less. Both features are due to loss of the eleven ndh genes in the Najas flexilis plastid. In angiosperms, the absence of ndh genes has been related mainly to the loss of photosynthetic function in parasitic plants. The ndh genes encode the NAD(P)H dehydrogenase complex, believed essential in terrestrial environments, where it increases photosynthetic efficiency in variable light intensities. The modified structure of the N. flexilis plastid genome suggests that adaptation to submersed environments, where light is scarce, has involved the loss of the NDH complex in at least some photosynthetic angiosperms. PMID:23861923

  2. Harm of Antibiotics in Aquatic Environment on Health%水环境中抗生素对健康的危害

    Institute of Scientific and Technical Information of China (English)

    胡譞予

    2015-01-01

    抗生素的不合理和不规范使用所造成的水环境污染问题日益受到人们的重视。本文综述了水环境中抗生素污染的来源及对生态环境和人体健康的危害,指出医用抗生素、农用抗生素和制药工业废水中的抗生素是最高污染源头。抗生素进入水体后,给水生生态系统造成不良影响,不仅诱导产生耐药性细菌,也使水生生物受到影响;还可在农副产品中残留,通过饮水、食物链等方式对人体健康构成潜在的威胁,严重干扰人体的各项生理机能,破坏人体免疫系统,降低人体的免疫功能。%The water pollution problem caused by the unreasonable and nonstandard using of antibiotics has raised extensive concerns in recent years. This paper reviews the sources of antibiotic pollution in the aquatic environment and its harm to the ecological environment and human health, points out that medical antibiotics, agricultural antibiotics and antibiotics in pharmaceutical wastewater are the upmost sources of pollution. Antibiotics polluted in the water can cause adverse effects to the aquatic ecosystem, which can not only induce bacterial resistance and affect the aquatic organisms, but also remain in agricultural products, thus pose a potential threat to human health through drinking water, food chain, etc, then seriously disturb the physiological function of human body, damage the body’s immune system and reduce immunologic function of human body.

  3. Cell-Based Sensor System Using L6 Cells for Broad Band Continuous Pollutant Monitoring in Aquatic Environments

    Directory of Open Access Journals (Sweden)

    Evamaria Stütz

    2012-03-01

    Full Text Available Pollution of drinking water sources represents a continuously emerging problem in global environmental protection. Novel techniques for real-time monitoring of water quality, capable of the detection of unanticipated toxic and bioactive substances, are urgently needed. In this study, the applicability of a cell-based sensor system using selected eukaryotic cell lines for the detection of aquatic pollutants is shown. Readout parameters of the cells were the acidification (metabolism, oxygen consumption (respiration and impedance (morphology of the cells. A variety of potential cytotoxic classes of substances (heavy metals, pharmaceuticals, neurotoxins, waste water was tested with monolayers of L6 cells (rat myoblasts. The cytotoxicity or cellular effects induced by inorganic ions (Ni2+ and Cu2+ can be detected with the metabolic parameters acidification and respiration down to 0.5 mg/L, whereas the detection limit for other substances like nicotine and acetaminophen are rather high, in the range of 0.1 mg/L and 100 mg/L. In a close to application model a real waste water sample shows detectable signals, indicating the existence of cytotoxic substances. The results support the paradigm change from single substance detection to the monitoring of overall toxicity.

  4. Development of naturally occurring siliceous material for the preferential removal of thorium from U-Th from aquatic environment

    International Nuclear Information System (INIS)

    During this work highly particle reactive nature of thorium was exploited for the separation of Th from aquatic stream containing U/Th. The Kd value of Th(IV) ions is 106 which is two order of magnitude higher than uranium (IV and VI). Laboratory simulated experiments were conducted to study the preferential removal of thorium by using siliceous material having particle size of about 2,000 μm. Siliceous material was prepared by decomposing the organic layer on soil particles by giving treatment with HNO3 and H2O2. Experimental solutions were generated by spiking the surface water with Th (NO3)4 and UO2(NO3)2. Experimental results shows preferential uptake of Th compared to U by siliceous material. This association is further improved by coating the siliceous material with high and low molecular weight organic materials i.e. humic and fulvic acid, respectively. Characterization of the organic material was done by ATR-FTIR whereas determination of Th was done by ICP-OES and alpha spectrometry. Experimental results clearly showed that Th and U sorption capacity is 1 and 0.3 μg mg-1 (w/w), respectively, in case of siliceous material. Thorium sorption is increased five and eight times in the case of coating with fulvic acid and humic acid, respectively. Whereas the same does not shows any pronounced impact on sorption of uranium. (author)

  5. Cell-based sensor system using L6 cells for broad band continuous pollutant monitoring in aquatic environments.

    Science.gov (United States)

    Kubisch, Rebekka; Bohrn, Ulrich; Fleischer, Maximilian; Stütz, Evamaria

    2012-01-01

    Pollution of drinking water sources represents a continuously emerging problem in global environmental protection. Novel techniques for real-time monitoring of water quality, capable of the detection of unanticipated toxic and bioactive substances, are urgently needed. In this study, the applicability of a cell-based sensor system using selected eukaryotic cell lines for the detection of aquatic pollutants is shown. Readout parameters of the cells were the acidification (metabolism), oxygen consumption (respiration) and impedance (morphology) of the cells. A variety of potential cytotoxic classes of substances (heavy metals, pharmaceuticals, neurotoxins, waste water) was tested with monolayers of L6 cells (rat myoblasts). The cytotoxicity or cellular effects induced by inorganic ions (Ni(2+) and Cu(2+)) can be detected with the metabolic parameters acidification and respiration down to 0.5 mg/L, whereas the detection limit for other substances like nicotine and acetaminophen are rather high, in the range of 0.1 mg/L and 100 mg/L. In a close to application model a real waste water sample shows detectable signals, indicating the existence of cytotoxic substances. The results support the paradigm change from single substance detection to the monitoring of overall toxicity. PMID:22737014

  6. Ethinyl Estradiol and Other Human Pharmaceutical Estrogens in the Aquatic Environment: A Review of Recent Risk Assessment Data

    OpenAIRE

    Laurenson, James P.; Bloom, Raanan A.; Page, Stephen; Sadrieh, Nakissa

    2014-01-01

    Interest in pharmaceuticals in the environment has increased substantially in recent years. Several studies in particular have assessed human and ecological risks from human pharmaceutical estrogens, such as 17α-ethinyl estradiol (EE2). Regulatory action also has increased, with the USA and other countries developing rules to address estrogens and other pharmaceuticals in the environment. Accordingly, the Center for Drug Evaluation and Research at the US Food and Drug Administration has condu...

  7. A Simple Model of Tetracycline Antibiotic Resistance in the Aquatic Environment (with Application to the Poudre River)

    OpenAIRE

    Sarah Sanchez; Xiaodan Ruan; Hellweger, Ferdi L.

    2011-01-01

    Antibiotic resistance is a major concern, yet it is unclear what causes the relatively high densities of resistant bacteria in the anthropogenically impacted environment. There are various possible scenarios (hypotheses): (A) Input of resistant bacteria from wastewater and agricultural sources is significant, but they do not grow in the environment; (B) Input of resistant bacteria is negligible, but the resistant bacteria (exogenous or endogenous) grow due to the selection pressure of the ant...

  8. Investigating the significance of dissolved organic contaminants in aquatic environments: coupling passive sampling with in vitro bioassays.

    Science.gov (United States)

    Emelogu, Emmanuel S; Pollard, Pat; Robinson, Craig D; Smedes, Foppe; Webster, Lynda; Oliver, Ian W; McKenzie, Craig; Seiler, T B; Hollert, Henner; Moffat, Colin F

    2013-01-01

    We investigated the feasibility of coupling passive sampling and in vitro bioassay techniques for both chemical and ecotoxicological assessment of complex mixtures of organic contaminants in water. Silicone rubber passive sampling devices (SR-PSDs) were deployed for 8-9 weeks in four streams and an estuary of an agricultural catchment in North East (NE) Scotland. Extracts from the SR-PSDs were analysed for freely dissolved hydrophobic organic contaminants (HOCs) and screened for wide range of pesticides. The total concentrations of dissolved PAHs (∑PAH(40), parent and branched) in the water column of the catchment varied from 38 to 69 ng L(-1), whilst PCBs (∑PCB(32)) ranged 0.02-0.06 ng L(-1). A number and level of pesticides and acid/urea herbicides of varying hydrophobicity (logK(OW)s ~2.25 to ~5.31) were also detected in the SR extracts, indicating their occurrence in the catchment. The acute toxicity and EROD induction potentials of SR extracts from the study sites were evaluated with rainbow trout liver (Oncorhynchus mykiss; RTL-W1) cell line. Acute cytotoxicity was not observed in cells following 48 h exposure to the SR extracts using neutral red uptake assay as endpoint. But, on a sublethal level, for every site, statistically significant EROD activity was observed to some degree following 72 h exposure to extracts, indicating the presence of compounds with dioxin-like effect that are bioavailable to aquatic organisms in the water bodies of the catchment. Importantly, only a small fraction of the EROD induction could be attributed to the PAHs and PCBs that were determined. This preliminary study demonstrates that the coupling of silicone rubber passive sampling techniques with in vitro bioassays is feasible and offers a cost effective early warning signal on water quality deterioration. PMID:22850278

  9. Isomer-specific analysis of nonylphenols with estrogenic activity and their distribution in aquatic environment in relation to endocrine disrupters

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Y.S.; Katase, T.; Inoue, T. [Nihon Univ., Fujisawa, Kanagawa (Japan). College of Bioresource Sciences; Horii, Y.; Yamashita, N. [National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki (Japan); Makino, M.; Uchiyama, T.; Fujimoto, Y. [Nihon Univ., Chiba (Japan). College of Pharmacy

    2004-09-15

    The effect of estrogen-exposure on levels of a larval storage protein of Balanus amphitrite, cypris major protein (CMP), which is related to barnacle vitellin, has been examined at low concentrations (0.01-1.0 {mu}g/l) of 4-nonylphenol (NP) and 17{beta}-estradiol (E2) (1.0 {mu}g/l) from egg hatching until the nauplius cypris stage. Eventually, the exposure to 0.01 {mu}g/l of NP led to a ca. 50% increase in the optical density of the CMP. There are theoretically ca. 170 kinds of isomers of NP, based on the structure of the nonyl side chain in NP. We fractionated a commercial NP by high performance liquid chromatography (HPLC) to give six fractions (Fr. 1- Fr. 6). Fr. 3 - Fr. 5 were further separated to afford 14 fractions by using gas chromatograph equipped with a preparative fraction collector (GC-PFC) and 11 NP isomers were identified by gas chromatograph equipped with mass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR). The chemical structures of 11 isomers (NP1 to NP14) were characterized and estrogenicities of the selected isomers were tested in recombinant yeast screen system. The 4-(1,1-dimethyl-2-ethyl-pentyl)- phenol (NP7) was found to exhibit the highest estrogenic activity corresponding to 1.9 x 10{sup -3} that of E2. The NP4 and 6 were structurally in diastereomer. The individual isomer of NP in aquatic samples taken from Ariake Sea and Tokyo, Japan was analyzed by steam distillation extraction in the present study.

  10. Monovalent monatomic ions in biological environments : insights from computational biophysics studies

    OpenAIRE

    Zhang, Chao

    2012-01-01

    Monovalent monoatomic ions (Na+, K+, Cl-, H+) are ubiquitously present in biological systems. They are indispensable for various life functions, such as keeping the heart beating and converting the energy from food. Complementary to experiments, molecular simulations indeed provide a computational microscope to probe the structure, dynamics and energetics of these ions in biological environments. One big challenge of computational studies is to accurately model the potential energy surface of...

  11. Possible use of EPDM in radioactive waste disposal: Long term low dose rate and short term high dose rate irradiation in aquatic and atmospheric environment

    International Nuclear Information System (INIS)

    In this study, changes in the properties of ethylene propylene diene terpolymer (EPDM) irradiated with different dose rates in ambient atmosphere and aqueous environment were investigated. Irradiations were carried out both with low dose and high dose rate irradiation sources. EPDM samples which were differentiated from each other by peroxide type and 5-ethylidene 2-norbornene (ENB) contents were used. Long term low dose rate irradiations were carried out for the duration of up to 2.5 years (total dose of 1178 kGy) in two different irradiation environments. Dose rates (both high and low), irradiation environments (in aquatic and open to atmosphere), and peroxide types (aliphatic or aromatic) were the parameters studied. Characterization of irradiated EPDM samples were performed by hardness, compression, tensile, dynamic mechanical analysis (DMA), TGA–FTIR, ATR-FTIR, XRD and SEM tests. It was observed that the irradiation in water environment led to a lower degree of degradation when compared to that of irradiation open to atmosphere for the same irradiation dose. In addition, irradiation environment, peroxide type and dose rate had effects on the extent of change in the properties of EPDM. It was observed that EPDM is relatively radiation resistant and a candidate polymer for usage in radioactive waste management. - Highlights: ► Possible use of EPDM in radioactive waste management was studied. ► The low dose rate irradiations were carried out for duration of up to 2.5 years. ► Characterizations of irradiated samples were performed. ► EPDM could possibly be a candidate material to be used in the radioactive waste management.

  12. Sustainable exploitation and management of aquatic resources

    DEFF Research Database (Denmark)

    Neuenfeldt, Stefan; Köster, Fritz

    2014-01-01

    surrounding environment.Freshwater fisheries and ecology is devoted to looking at the behaviour of particular speciesof fish and their interaction with the environment. Coastal ecology deals with the structure and function ofthe ecosystems as a habitat for fish and shellfish as well as with coastal area...... ecosystem approach whichutilizes synergies in natural and technical sciencedisciplines. DTU Aqua advises the Danish Ministry ofFood, Agriculture and Fisheries and other publicauthorities, the commercial fisheries, theaquaculture industry and international commissions.DTU Aqua deals with all types ofaquatic...... ocean and how these factors impact the living conditions formarine organisms. Population genetics aims at gaining knowledge on how to preserve and managebiodiversity sustainably. Individual biology deals with the biology of aquatic organisms and theirinteraction with other organisms and with the...

  13. Impact of dead and sunken water hyacinth on biotic communities, the aquatic environment and socio-economic activities

    OpenAIRE

    Ogutu-Ohwayo, R.; Balirwa, J.S.; Twongo, T.; Mugidde, R.; Odongkara, O.

    2002-01-01

    The mobile water hyacinth, which was produced in growth zones, especially Murchison Bay, was mainly exported to three sheltered storage bays (Thruston, Hannington and Waiya). Between 1996 and May 1998, the mobile form of water hyacinth occupied about 800 ha in Thruston Bay, 750 ha in Hannington Bay and 140 ha in Waiya Bay). Biological control weevils and other factors, including localised nutrient depletion, weakened the weed that was confined to the bays and it sunk around October 1998. The ...

  14. Aquatic Sediments.

    Science.gov (United States)

    Sanville, W. D.; And Others

    1978-01-01

    Presents a literature review of aquatic sediments and its effect upon water quality, covering publications of 1976-77. This review includes: (1) sediment water interchange; (2) chemical and physical characterization; and (3) heavy water in sediments. A list of 129 references is also presented. (HM)

  15. Nonmagnetotactic Multicellular Prokaryotes from Low-Saline, Nonmarine Aquatic Environments and Their Unusual Negative Phototactic Behavior▿ †

    OpenAIRE

    Lefèvre, Christopher T; Abreu, Fernanda; Lins, Ulysses; Dennis A. Bazylinski

    2010-01-01

    Magnetotactic multicellular prokaryotes (MMPs) are unique magnetotactic bacteria of the Deltaproteobacteria class and the first found to biomineralize the magnetic mineral greigite (Fe3S4). Thus far they have been reported only from marine habitats. We questioned whether MMPs exist in low-saline, nonmarine environments. MMPs were observed in samples from shallow springs in the Great Boiling Springs geothermal field and Pyramid Lake, both located in northwestern Nevada. The temperature at all ...

  16. Aquatic models, genomics and chemical risk management.

    Science.gov (United States)

    Cheng, Keith C; Hinton, David E; Mattingly, Carolyn J; Planchart, Antonio

    2012-01-01

    The 5th Aquatic Animal Models for Human Disease meeting follows four previous meetings (Nairn et al., 2001; Schmale, 2004; Schmale et al., 2007; Hinton et al., 2009) in which advances in aquatic animal models for human disease research were reported, and community discussion of future direction was pursued. At this meeting, discussion at a workshop entitled Bioinformatics and Computational Biology with Web-based Resources (20 September 2010) led to an important conclusion: Aquatic model research using feral and experimental fish, in combination with web-based access to annotated anatomical atlases and toxicological databases, yields data that advance our understanding of human gene function, and can be used to facilitate environmental management and drug development. We propose here that the effects of genes and environment are best appreciated within an anatomical context - the specifically affected cells and organs in the whole animal. We envision the use of automated, whole-animal imaging at cellular resolution and computational morphometry facilitated by high-performance computing and automated entry into toxicological databases, as anchors for genetic and toxicological data, and as connectors between human and model system data. These principles should be applied to both laboratory and feral fish populations, which have been virtually irreplaceable sentinals for environmental contamination that results in human morbidity and mortality. We conclude that automation, database generation, and web-based accessibility, facilitated by genomic/transcriptomic data and high-performance and cloud computing, will potentiate the unique and potentially key roles that aquatic models play in advancing systems biology, drug development, and environmental risk management. PMID:21763781

  17. Effects of Conceptual Change Text Based Instruction on Ecology, Attitudes toward Biology and Environment

    Science.gov (United States)

    Çetin, Gülcan; Ertepinar, Hamide; Geban, Ömer

    2015-01-01

    The purpose of this study is to investigate the effects of the conceptual change text based instruction on ninth grade students' understanding of ecological concepts, and attitudes toward biology and environment. Participants were 82 ninth grade students in a public high school in the Northwestern Turkey. A treatment was employed over a…

  18. Perceptions of the Learning Environment and Associations with Cognitive Achievement among Gifted Biology Students

    Science.gov (United States)

    Rita, Ronald D.; Martin-Dunlop, Catherine S.

    2011-01-01

    This study assessed the perceptions of 146 gifted and 115 non-gifted high school biology students and investigated associations between student perceptions and cognitive achievement. The What Is Happening In this Class? (WIHIC) was used to assess perceptions of actual and preferred learning environments. Data indicated that all students preferred…

  19. Uranium in the Near-shore Aquatic Food Chain: Studies on Periphyton and Asian Clams

    Energy Technology Data Exchange (ETDEWEB)

    Bunn, Amoret L.; Miley, Terri B.; Eslinger, Paul W.; Brandt, Charles A.; Napier, Bruce A.

    2007-12-31

    The benthic aquatic organisms in the near-shore environment of the Columbia River are the first biological receptors that can be exposed to groundwater contaminants coming from the U.S. Department of Energy's Hanford Site. The primary contaminant of concern in the former nuclear fuels processing area at the Site, known as the 300 Area, is uranium. Currently, there are no national clean up criteria for uranium and ecological receptors. This report summarizes efforts to characterize biological uptake of uranium in the food chain of the benthic aquatic organisms and provide information to be used in future assessments of uranium and the ecosystem.

  20. Uranium in the Near-shore Aquatic Food Chain: Studies on Periphyton and Asian Clams

    International Nuclear Information System (INIS)

    The benthic aquatic organisms in the near-shore environment of the Columbia River are the first biological receptors that can be exposed to groundwater contaminants coming from the U.S. Department of Energy's Hanford Site. The primary contaminant of concern in the former nuclear fuels processing area at the Site, known as the 300 Area, is uranium. Currently, there are no national clean up criteria for uranium and ecological receptors. This report summarizes efforts to characterize biological uptake of uranium in the food chain of the benthic aquatic organisms and provide information to be used in future assessments of uranium and the ecosystem.

  1. Chemical, biological and toxicological investigation of oil drilling impacts to aquatic resources in the Yellowbank Slough region near New Haven, Illinois

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A survey of contaminants in sediments and aquatic macroinvertebrates at several locations on the proposed Yellowbank Slough National Wildlife Refuge was conducted...

  2. Microplastic as a Vector for Chemicals in the Aquatic Environment: Critical Review and Model-Supported Reinterpretation of Empirical Studies.

    Science.gov (United States)

    Koelmans, Albert A; Bakir, Adil; Burton, G Allen; Janssen, Colin R

    2016-04-01

    The hypothesis that 'microplastic will transfer hazardous hydrophobic organic chemicals (HOC) to marine animals' has been central to the perceived hazard and risk of plastic in the marine environment. The hypothesis is often cited and has gained momentum, turning it into paradigm status. We provide a critical evaluation of the scientific literature regarding this hypothesis. Using new calculations based on published studies, we explain the sometimes contrasting views and unify them in one interpretive framework. One explanation for the contrasting views among studies is that they test different hypotheses. When reframed in the context of the above hypothesis, the available data become consistent. We show that HOC microplastic-water partitioning can be assumed to be at equilibrium for most microplastic residing in the oceans. We calculate the fraction of total HOC sorbed by plastics to be small compared to that sorbed by other media in the ocean. We further demonstrate consistency among (a) measured HOC transfer from microplastic to organisms in the laboratory, (b) measured HOC desorption rates for polymers in artificial gut fluids (c) simulations by plastic-inclusive bioaccumulation models and (d) HOC desorption rates for polymers inferred from first principles. We conclude that overall the flux of HOCs bioaccumulated from natural prey overwhelms the flux from ingested microplastic for most habitats, which implies that microplastic ingestion is not likely to increase the exposure to and thus risks of HOCs in the marine environment. PMID:26946978

  3. Marketing the use of the space environment for the processing of biological and pharmaceutical materials

    Science.gov (United States)

    1984-01-01

    The perceptions of U.S. biotechnology and pharmaceutical companies concerning the potential use of the space environment for the processing of biological substances was examined. Physical phenomena that may be important in space-base processing of biological materials are identified and discussed in the context of past and current experiment programs. The capabilities of NASA to support future research and development, and to engage in cooperative risk sharing programs with industry are discussed. Meetings were held with several biotechnology and pharmaceutical companies to provide data for an analysis of the attitudes and perceptions of these industries toward the use of the space environment. Recommendations are made for actions that might be taken by NASA to facilitate the marketing of the use of the space environment, and in particular the Space Shuttle, to the biotechnology and pharmaceutical industries.

  4. Surface coating affects behavior of metallic nanoparticles in a biological environment

    Science.gov (United States)

    Jurašin, Darija Domazet; Ćurlin, Marija; Capjak, Ivona; Crnković, Tea; Lovrić, Marija; Babič, Michal; Horák, Daniel; Gajović, Srećko

    2016-01-01

    Summary Silver (AgNPs) and maghemite, i.e., superparamagnetic iron oxide nanoparticles (SPIONs) are promising candidates for new medical applications, which implies the need for strict information regarding their physicochemical characteristics and behavior in a biological environment. The currently developed AgNPs and SPIONs encompass a myriad of sizes and surface coatings, which affect NPs properties and may improve their biocompatibility. This study is aimed to evaluate the effects of surface coating on colloidal stability and behavior of AgNPs and SPIONs in modelled biological environments using dynamic and electrophoretic light scattering techniques, as well as transmission electron microscopy to visualize the behavior of the NP. Three dispersion media were investigated: ultrapure water (UW), biological cell culture medium without addition of protein (BM), and BM supplemented with common serum protein (BMP). The obtained results showed that different coating agents on AgNPs and SPIONs produced different stabilities in the same biological media. The combination of negative charge and high adsorption strength of coating agents proved to be important for achieving good stability of metallic NPs in electrolyte-rich fluids. Most importantly, the presence of proteins provided colloidal stabilization to metallic NPs in biological fluids regardless of their chemical composition, surface structure and surface charge. In addition, an assessment of AgNP and SPION behavior in real biological fluids, rat whole blood (WhBl) and blood plasma (BlPl), revealed that the composition of a biological medium is crucial for the colloidal stability and type of metallic NP transformation. Our results highlight the importance of physicochemical characterization and stability evaluation of metallic NPs in a variety of biological systems including as many NP properties as possible. PMID:26977382

  5. The toxicity of molybdate to freshwater and marine organisms. II. Effects assessment of molybdate in the aquatic environment under REACH

    International Nuclear Information System (INIS)

    The REACH Molybdenum Consortium initiated an extensive research program in order to generate robust PNECs, based on the SSD approach, for both the freshwater and marine environments. This activity was part of the REACH dossier preparation and to form the basis for scientific dialogues with other national and international regulatory authorities. Chronic ecotoxicity data sets for the freshwater and marine environments served as starting point for the derivation of PNECs for both compartments, in accordance with the recommended derivation procedures established by the European Chemicals Agency (ECHA). The HC5,50%s that were derived from the generated Species Sensitivity Distributions were 38.2 mg Mo/L and 5.75 mg Mo/L for the freshwater and marine water compartment, respectively. Uncertainty analysis on both data sets and available data on bioaccumulation at high exposure levels justified an assessment factor of 3 on both HC5,50% leading to a PNECfreshwater of 12.7 mg Mo/L and a PNECmarine of 1.92 mg Mo/L. As there are currently insufficient ecotoxicological data available for the derivation of PNECs in the sediment compartment, the equilibrium partitioning method was applied; typical KD-values for both the freshwater and marine compartments were identified and combined with the respective PNEC, leading to a PNECsediment of 22,600 mg/kg dry weight and 1980 mg/kg dry weight for freshwater and marine sediments, respectively. The chronic data sets were also used for the derivation of final chronic values using the procedures that are outlined by the US Environmental Protection Agency for deriving such water benchmarks. Comparing PNECs with FCVs showed that both methodologies result in comparable protective concentration levels for molybdenum in the environment. -- Highlights: ► Derivation of freshwater and marine safe levels based on chronic ecotoxicity data. ► PNEC derivation according to EU guidance, using the statistical extrapolation. ► Determination of a

  6. The microzooplankton and its distribution in different aquatic environment; Il microzooplancton e la sua distribuzione nei diversi ambienti

    Energy Technology Data Exchange (ETDEWEB)

    Creo, C. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Ambiente; Grenni, P.

    1999-07-01

    In this work some examples of studies performed with the use of microzooplankton as biological indicator are reported. [Italian] Scopo del lavoro e' quello di dimostrare come lo studio della distribuzione del microzooplancton in ambienti aquatici, possa permettere la caratterizzazione trofica dell'ambiente oggetto di studio. Il microzooplancton, infatti, essendo un componente fondamentale della catena trofica di differenti ambienti acquatici, puo' essere considerato un buon {sup i}ndicatore biologico{sup .} E' quindi riportata un'ampia ed approfondita analisi sistematica, necessaria al fine di individuarne le diverse specie dalla cui presenza (oltreche' dal numero degli esemplari) e' possibile desumere lo stato chimico-fisico e trofico di un determinato ambiente acquatico. Sono poi indicati i diversi metodi per il campionamento, la conservazione, la concentrazione ed il conteggio del microzooplancton; in particolare per la concentrazione ed il conteggio sono indicate e sperimentate nuove tecniche effettuate rispettivamente con l'ausilio della concentrazione dei campioni a flusso tangenziale e con l'utilizzo di coloranti fluorescenti.

  7. Methods for the determination of low-level actinide concentrations and their behaviour in the aquatic environment

    International Nuclear Information System (INIS)

    Intentional and accidental releases have contaminated the environment with radionuclides, posing a potential health hazard to populations of the polluted regions. Low concentrations of the actinides in the environment and complex sample matrices have made their determination a time consuming and complicated task. Separation methods based on anion exchange and extraction chromatography were developed, and subsequently modified, for analysis of different sample matrices in this work. These methods were used for the investigations of the behaviour of actinides in the environment. Chemical properties play an important role in the phenomena affecting the migration of radionuclides. The method based on anion exchange was used to study the behaviour of U in a small U-Th deposit and also the behaviour of Pu, Am and Cm in a lake system after the Chernobyl accident. The speciation of U and Pu in natural waters has also been investigated. A trend of higher 234U/238U activity ratios with lower 238U concentrations was seen in the ground waters in the Palmottu analogue study site in southern Finland. This indicates chemical leaching of U(VI) in oxidising conditions and preferable dissolution of 234U due to the recoil effects of the alpha decay in reducing conditions. The factors affecting the distribution of U concentrations and the 234U/238U activity ratios in filtered ground water and the particulate fraction in the Palmottu are also discussed. The concentrations of Pu, Am and Cm in filtered water, particulate and surface sediment samples in Lake Paeijaenne in southern Finland have been determined. Pu, Am and Cm fallout from the Chernobyl accident was minor compared to global fallout from atmospheric nuclear weapon tests. Based on the 238Pu/239,240Pu isotopic ratio, only 10 % of the Pu in the surface layer of the bottom sediment derived from the Chernobyl accident. Three months after the accident, 73 % of the total 239,240Pu concentration was in the surface layer of the bottom

  8. Methods for the determination of low-level actinide concentrations and their behaviour in the aquatic environment

    Energy Technology Data Exchange (ETDEWEB)

    Pilvioe, R

    1998-12-31

    Intentional and accidental releases have contaminated the environment with radionuclides, posing a potential health hazard to populations of the polluted regions. Low concentrations of the actinides in the environment and complex sample matrices have made their determination a time consuming and complicated task. Separation methods based on anion exchange and extraction chromatography were developed, and subsequently modified, for analysis of different sample matrices in this work. These methods were used for the investigations of the behaviour of actinides in the environment. Chemical properties play an important role in the phenomena affecting the migration of radionuclides. The method based on anion exchange was used to study the behaviour of U in a small U-Th deposit and also the behaviour of Pu, Am and Cm in a lake system after the Chernobyl accident. The speciation of U and Pu in natural waters has also been investigated. A trend of higher {sup 234}U/{sup 238}U activity ratios with lower {sup 238}U concentrations was seen in the ground waters in the Palmottu analogue study site in southern Finland. This indicates chemical leaching of U(VI) in oxidising conditions and preferable dissolution of {sup 234}U due to the recoil effects of the alpha decay in reducing conditions. The factors affecting the distribution of U concentrations and the {sup 234}U/{sup 238}U activity ratios in filtered ground water and the particulate fraction in the Palmottu are also discussed. The concentrations of Pu, Am and Cm in filtered water, particulate and surface sediment samples in Lake Paeijaenne in southern Finland have been determined. Pu, Am and Cm fallout from the Chernobyl accident was minor compared to global fallout from atmospheric nuclear weapon tests. Based on the {sup 238}Pu/{sup 239,240}Pu isotopic ratio, only 10 % of the Pu in the surface layer of the bottom sediment derived from the Chernobyl accident. Three months after the accident, 73 % of the total {sup 239

  9. Is there a risk for the aquatic environment due to the existence of emerging organic contaminants in treated domestic wastewater? Greece as a case-study.

    Science.gov (United States)

    Thomaidi, Vasiliki S; Stasinakis, Athanasios S; Borova, Viola L; Thomaidis, Nikolaos S

    2015-01-01

    The ecological threat associated with emerging pollutants detected in wastewater was estimated in country level. Treated wastewater was analyzed for pharmaceuticals and illicit drugs; whereas the concentrations of all emerging contaminants determined in Greek Sewage Treatment Plants were recorded through literature review. Toxicity data was collected after literature review or using ECOSAR and risk quotients (RQs) were calculated for treated wastewater and 25 Greek rivers, for 3 different aquatic organisms (fish, daphnia magna, algae). According to the results, monitoring data was available for 207 micropollutants belonging to 8 different classes. RQ>1 was calculated for 30 compounds in secondary treated wastewater. Triclosan presented RQ>1 (in algae) for all studied rivers; decamethylcyclopentasilane (in daphnia magna), caffeine (in algae) and nonylphenol (in fish) presented RQ>1 in rivers with dilution factors (DF) equal or lower to 1910, 913 and 824, respectively. The class of emerging contaminants that present the greatest threat due to single or mixture toxicity was endocrine disrupters. The mixture of microcontaminants seems to pose significant ecological risk, even in rivers with DF equal to 2388. Future national monitoring programs should include specific microcontaminants that seem to possess environment risk to surface water. PMID:25464317

  10. Species analysis of organotin compounds to investigate their pathway in the aquatic environment; Speziesanalytik von zinnorganischen Verbindungen zur Aufklaerung ihrer Biopfade in der aquatischen Umwelt

    Energy Technology Data Exchange (ETDEWEB)

    Kuballa, J. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Physikalische und Chemische Analytik

    1997-12-31

    In this thesis the sorption, transport and accumulation behaviour of organotin compounds in the aquatic environment was investigated in order to assess and evaluate the toxic potential. In situ derivatization with sodiumthetraethylborate and extraction with hexane were employed to isolate the tin species from the matrices. Separation and quantification were performed using on-line gas chromatorgraphy coupled with atomic absorption spectrometry. The main conclusion of this work is that organotin compounds show a characteristic bioaccumulation behaviour, which is influenced by the solubility of the species in combination with lipophily and sorption on particles, humic substances and biofilms. (orig.) [Deutsch] In der vorliegenden Arbeit wurden das Sorptions-, Transport- und Akkumulationsverhalten von Organozinnverbindungen in der aquatischen Umwelt untersucht mit dem Ziel einer Abschaetzung und Bewertung des oekologischen Schaedigungspotentials. Die Isolierung der Zinnspezies aus den Matrizes gelang mit der In-Situ-Derivatisierung mit Natriumtetraethylborat und Extraktion mit Hexan. Die Trennung und Quantifizierung erfolgte mittels Gaschromatographie on-line gekoppelt mit Atomabsorptionsspektrometrie. Die wichtigste Aussage dieser Arbeit ist, dass zinnorganische Verbindungen ein charakteristisches Bioakkumulationsverhalten aufweisen, das wesentlich von der Wasserloeslichkeit der Spezies in Verbindung mit der Lipophilie und der Bindung an Partikel, Huminstoffe und Biofilme beeinflusst wird. (orig.)

  11. Evaluation of selected ubiquitous contaminants in the aquatic environment and their transformation products. A pilot study of their removal from a sewage treatment plant.

    Science.gov (United States)

    Bueno, M J Martínez; Uclés, S; Hernando, M D; Dávoli, E; Fernández-Alba, A R

    2011-03-01

    A simple method using direct sample injection combined with liquid chromatography tandem mass spectrometry has been developed for the simultaneous analysis of six alkaloid compounds in environmental samples. The target list includes two psychostimulants (nicotine and caffeine), three metabolites (cotinine, nicotinic acid and paraxanthine) and a coffee chemical (trigonelline). The analytical method was evaluated in three different matrices (surface water, influent and effluent wastewater). The method developed showed an adequate sensitivity, below 0.6 μg L(-1) for wastewater and 0.1 μg L(-1) for river matrices, without any prior treatment of the samples. Finally, the methodology was applied to real samples for evaluation of their removal from a sewage treatment plant and their persistence/fate in the aquatic environment. All compounds studied in this work were detected at all sampling points collected along the Henares River. However, nicotinic acid was only detected three times in treated sewage samples at levels above its detection limit. PMID:21333319

  12. Behavior of 226Ra in the aquatic environment of the uranium mine region of Pocos de Caldas, MG, Brazil

    International Nuclear Information System (INIS)

    A sampling and analytical program for 238U, 226Ra and 210Pb was started, at first, in the uranium mine region, at Pocos de Caldas, MG, Brazil. Afterwards, the interaction was studied between 226Ra and local river sediments and waters. Peliminary studies were also done on the mobility of 226Ra retained on solid matter or soil, induced by local waters. Above normal concentrations of 238U, 226Ra and 210Pb were found in local waters, sediments and plants collected on the imediate vicinity of the mine. 226Ra distribution coefficients are on the order of 103 for the different samples assayed. It was concluded that, in the future, 226Ra discharged into liquid environment should be only temporarily retained by sediments. Its transport by surface waters should be predominantly in the soluble form. 226Ra should become the critical radionuclide in terms of internal radiation dose on the local population, due to its ingestion with water. 226Ra retained on solid supports is mobilized by local waters and its solubilization is dependent on the volume of water passed through. (M.A.)

  13. Genotyping of Pseudomonas aeruginosa isolates from lung transplant recipients and aquatic environment-detected in-hospital transmission.

    Science.gov (United States)

    Johansson, Ewa; Welinder-Olsson, Christina; Gilljam, Marita

    2014-02-01

    Lung infection with Pseudomonas aeruginosa is common in lung transplant recipients and may lead to severe complications. Bacteriological surveillance aims to detect transmission of microbes between hospital environment and patients. We sought to determine whether genotyping of P. aeruginosa isolates could improve identifications of pathways of infection. From 2004 to 2009, we performed genotyping with multiple-locus variable number of tandem repeats analysis (MLVA) and pulsed-field gel electrophoresis (PFGE) of P. aeruginosa isolates cultured from lung transplant recipients at Sahlgrenska University Hospital, Gothenburg. During a small outbreak in 2008, cultivation and genotyping of isolates from sink and drains samples from the hospital ward were performed. Pseudomona aeruginosa from 11/18 patients were genotyped to unique strains. The remaining seven patients were carriers of a P. aeruginosa strain of cluster A genotype. Pseudomona aeruginosa was isolated in 4/8 water samples, typed by MLVA also as cluster A genotype and confirmed by PFGE to be similar or identical to the isolates from four transplanted patients. In conclusion, genotyping of isolates revealed a clonal relationship between patient and water isolates, indicating in-hospital transmission of P. aeruginosa. We suggest genotyping with MLVA for rapid routine surveillance, with the PFGE method used for extended, confirmatory analyses. PMID:24450429

  14. Microscopy and Molecular Biology Techniques for the Study of Biocenosis Diversity in Semi-Confined Environments

    Directory of Open Access Journals (Sweden)

    Franco Palla

    2010-12-01

    Full Text Available This study is part of a wider conservation project of artistic and anthropological finds located in the Grotto of the Saints (Licodia Eubea, Alia, Sicily, and represents an opportunity for  investigating the micro-and macro biological systems colonizing this particular environment. It is well-known that the  bio-receptivity of surfaces is strongly related to its constituent materials and environmental parameters, whose effects promote the establishment of specific biotic communities. This is particularly true for caves, hypogea and semi-confined environments and, in particular for the Grotto of the Saints, where besides the presence of different nutrient sources, there are also high humidity values, percolating water and an aerobiological exchange with the surrounding countryside. Moreover, the weathering of this structure is enhanced by the canyon effect of the wind and the day-night temperature range. The identification and characterization of the biocenosis present in this environment was performed combining microscopy (optical, fluorescent, CLSM and molecular biology analysis (DNA sequences. The aim was to identify the biological systems able to trigger the degradation processes, in order to plan their growth control and to prevent the colonization of the entire environment.

  15. Who Possesses Drug Resistance Genes in the Aquatic Environment? : Sulfamethoxazole (SMX) Resistance Genes among the Bacterial Community in Water Environment of Metro-Manila, Philippines

    OpenAIRE

    Satoru eSuzuki; Mitsuko eOgo; Miller, Todd W.; Akiko eShimizu; Hideshige eTakada; Maria Auxilia eSiringan

    2013-01-01

    Recent evidence has shown that antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) are ubiquitous in natural environments, including sites considered pristine. To understand the origin of ARGs and their dynamics, we must first define their actual presence in the natural bacterial assemblage. Here we found varying distribution profiles of sul genes in “colony forming bacterial assemblages” and “natural bacterial assemblages.” Our monitoring for antibiotic contamination r...

  16. Biologically inspired design framework for Robot in Dynamic Environments using Framsticks

    CERN Document Server

    S., Raja Mohamed

    2012-01-01

    Robot design complexity is increasing day by day especially in automated industries. In this paper we propose biologically inspired design framework for robots in dynamic world on the basis of Co-Evolution, Virtual Ecology, Life time learning which are derived from biological creatures. We have created a virtual khepera robot in Framsticks and tested its operational credibility in terms hardware and software components by applying the above suggested techniques. Monitoring complex and non complex behaviors in different environments and obtaining the parameters that influence software and hardware design of the robot that influence anticipated and unanticipated failures, control programs of robot generation are the major concerns of our techniques.

  17. BioGraphE: High-performance bionetwork analysis using the Biological Graph Environment

    Energy Technology Data Exchange (ETDEWEB)

    Chin, George; Chavarría-Miranda, Daniel; Nakamura, Grant C.; Sofia, Heidi J.

    2008-05-28

    Graphs and networks are common analysis representations for biological systems. Many traditional graph algorithms such as k-clique, k-coloring, and subgraph matching have great potential as analysis techniques for newly available data in biology. Yet, as the amount of genomic and bionetwork information rapidly grows, scientists need advanced new computational strategies and tools for dealing with the complexities of the bionetwork analysis and the volume of the data. We introduce a computational framework for graph analysis called the Biological Graph Environment (BioGraphE), which provides a general, scalable integration platform for connecting graph problems in biology to optimized computational solvers and high-performance systems. This framework enables biology researchers and computational scientists to identify and deploy network analysis applications and to easily connect them to efficient and powerful computational software and hardware that are specifically designed and tuned to solve complex graph problems. In our particular application of BioGraphE to support network analysis in genome biology, we investigate the use of a Boolean satisfiability solver known as Survey Propagation as a core computational solver and high-performance parallel systems that utilize multi-threaded architectures. In our application of BioGraphE to conduct bionetwork analysis of homology networks, we found that BioGraphE and a custom, parallel implementation of the Survey Propagation SAT solver were capable of solving very large bionetwork problems at high rates of execution on different high-performance computing platforms.

  18. Can aquatic macrophytes mobilize technetium by oxidizing their rhizosphere?

    International Nuclear Information System (INIS)

    Technetium (Tc) is very mobile in aerated surface environments, but is essentially immobile and biologically unavailable in anaerobic sediments. Aquatic macrophyte roots penetrate anaerobic sediments, carrying O2 downward and frequently creating oxidizing conditions in their rhizosphere. The authors hypothesized that this process could mobilize otherwise unavailable Tc, possibly leading to incorporation of Tc into human or animal foods. Through experiments with rice (Oryza sativa L.), and with a novel artificial macrophyte root, they concluded that this pathway is unlikely to be important for annual plants, especially in soils with a high biological oxygen demand. The relatively slow oxidation of Tc limited its mobilization by short-lived root systems

  19. Influence of Web-Aided Cooperative Learning Environment on Motivation and on Self-Efficacy Belief in Biology Teaching

    Science.gov (United States)

    Hevedanli, Murat

    2015-01-01

    The purpose of this study is to investigate the influence of the web-aided cooperative learning environment on biology preservice teachers' motivation and on their self-efficacy beliefs in biology teaching. The study was carried out with 30 biology preservice teachers attending a state university in Turkey. In the study, the pretest-posttest…

  20. Preparing Federal Coordinating Officers (FCOs) to operate in Chemical, Biological, Radiological, and Nuclear (CBRN) environments

    OpenAIRE

    Russell, Tony.

    2008-01-01

    CHDS State/Local In this thesis the Federal Emergency Management Agency's (FEMA) Federal Coordinating Officer (FCO) function is examined as it relates to Chemical, Biological, Radiological and Nuclear (CBRN) operations. It is suggested that targeted changes can be made to ensure the FCOs are better prepared to manage the additional complexities of a CBRN environment. The changes include addressing the FCOs from the systems approach- internally to improve the FCO personal and professio...

  1. The study on human health and environment by neutron activation analysis of biological samples

    International Nuclear Information System (INIS)

    - Choice of samples for the research goal and survey of individual food habit and sampling for the meaningful statistical output - Development of the optimum analytical method for the analysis of trace elements in biological samples such as hair, blood, and foods. - Quantitative analysis of several samples to identify the source of trace elements into human body. - Evaluation in view of health and environment to the trace elements in various sources which can be introduced inside human body

  2. Molecular Biology for the Environment: an EC-US hands-on Course in Environmental Biotechnology

    Energy Technology Data Exchange (ETDEWEB)

    Victor de Lorenzo; Juan Luis Ramos; Jerome Kukor; Gerben J. Zylstra

    2004-02-15

    One of the central goals of this activity is to bring together young scientists (at the late Ph.D. or early postdoctoral stages of their careers) in a forum that should result in future collaborations. The course is designed to give scientists hands-on experience in modern, up-to-date biotechnological methods at the interface between molecular biology and environmental biotechnology for the analysis of microorganisms and their activities with regard to the remediation of pollutants in the environment.

  3. A rational approach to selecting and ranking some pharmaceuticals of concern for the aquatic environment and their relative importance compared with other chemicals

    OpenAIRE

    Donnachie, Rachel L.; Johnson, Andrew C.; Sumpter, John P.

    2016-01-01

    Aquatic organisms can be exposed to thousands of chemicals discharged by the human population. Many of these chemicals are considered disruptive to aquatic wildlife; the literature on the impacts of these chemicals grows daily. However, since time and resources are not infinite, we must focus on the chemicals which represent the greatest threat. One group of chemicals of increasing concern is the pharmaceuticals, where the struggle is to identify which of them represent the greatest threat. I...

  4. An assessment of Hg in the freshwater aquatic environment related to long-range transported air pollution in Europe and North America (ICP Waters report 97/2009)

    OpenAIRE

    Ranneklev, S.; de Wit, H; Jenssen, M.; Skjelkvåle, B. L.

    2009-01-01

    Long-range transboundary atmospheric transport of the pollutant mercury (Hg) (LTRAP-Hg) poses an ecological threat to aquatic ecosystems and biota. Through fish consumption, mercury and its highly toxic and bioaccumulative organic form methylmercury (MeHg) may cause harmful effects on human health. Factors controlling the bioaccumulation of Hg in aquatic ecosystems are not well understood. In Scandinavia an increased content of Hg in piscivorous fish has been observed the last decade. Today, ...

  5. Aquatic food security:insights into challenges and solutions from an analysis of interactions between fisheries, aquaculture, food safety, human health, fish and human welfare, economy and environment

    OpenAIRE

    Jennings, Simon; Stentiford, Grant D.; Leocadio, Ana M.; Jeffery, Keith R; Metcalfe, Julian D.; Katsiadaki, Ioanna; Auchterlonie, Neil A.; Mangi, Stephen C.; Pinnegar, John K.; Ellis, Tim; Peeler, Edmund J; Luisetti, Tiziana; Baker-Austin, Craig; Brown, Mary; Catchpole, Thomas L.

    2016-01-01

    Fisheries and aquaculture production, imports, exports and equitability of distribution determine the supply of aquatic food to people. Aquatic food security is achieved when a food supply is sufficient, safe, sustainable, shockproof and sound: sufficient, to meet needs and preferences of people; safe, to provide nutritional benefit while posing minimal health risks; sustainable, to provide food now and for future generations; shock-proof, to provide resilience to shocks in production systems...

  6. Low-gravity Orbiting Research Laboratory Environment Potential Impact on Space Biology Research

    Science.gov (United States)

    Jules, Kenol

    2006-01-01

    One of the major objectives of any orbital space research platform is to provide a quiescent low gravity, preferably a zero gravity environment, to perform fundamental as well as applied research. However, small disturbances exist onboard any low earth orbital research platform. The impact of these disturbances must be taken into account by space research scientists during their research planning, design and data analysis in order to avoid confounding factors in their science results. The reduced gravity environment of an orbiting research platform in low earth orbit is a complex phenomenon. Many factors, among others, such as experiment operations, equipment operation, life support systems and crew activity (if it is a crewed platform), aerodynamic drag, gravity gradient, rotational effects as well as the vehicle structural resonance frequencies (structural modes) contribute to form the overall reduced gravity environment in which space research is performed. The contribution of these small disturbances or accelerations is precisely why the environment is NOT a zero gravity environment, but a reduced acceleration environment. This paper does not discuss other factors such as radiation, electromagnetic interference, thermal and pressure gradient changes, acoustic and CO2 build-up to name a few that affect the space research environment as well, but it focuses solely on the magnitude of the acceleration level found on orbiting research laboratory used by research scientists to conduct space research. For ease of analysis this paper divides the frequency spectrum relevant to most of the space research disciplines into three regimes: a) quasi-steady, b) vibratory and c) transient. The International Space Station is used as an example to illustrate the point. The paper discusses the impact of these three regimes on space biology research and results from space flown experiments are used to illustrate the potential negative impact of these disturbances (accelerations

  7. Solid waste deposits as a significant source of contaminants of emerging concern to the aquatic and terrestrial environments - A developing country case study from Owerri, Nigeria

    Energy Technology Data Exchange (ETDEWEB)

    Arukwe, Augustine, E-mail: arukwe@bio.ntnu.no [Department of Biology, Norwegian University of Science and Technology (NTNU), Hogskoleringen 5, 7491 Trondheim (Norway); Eggen, Trine [Bioforsk, Norwegian Institute for Agricultural and Environmental Research, Postveien 213, N-4353 Klepp St. (Norway); Moeder, Monika [Helmholtz Centre for Environmental Research UFZ, Department of Analytical Chemistry, Permoserstrasse 15, D-04318 Leipzig (Germany)

    2012-11-01

    isomers), metabolites of non-ionic surfactants (nonylphenol-polyethoxylates), UV-filter compound ethyl methoxy cinnamate (EHMC) and bisphenol A (BPA) were particularly determined in the sediment samples at high {mu}g/kg dry weight concentration. Measuring contaminants in such areas will help in increasing governmental, societal and industrial awareness on the extent and seriousness of the contamination both at waste disposal sites and surrounding terrestrial and aquatic environments. -- Highlights: Black-Right-Pointing-Pointer Solid waste management in developing countries Black-Right-Pointing-Pointer Solid waste as a significant source of contaminants of emerging concern Black-Right-Pointing-Pointer Contaminant leaching from solid waste to surrounding environment Black-Right-Pointing-Pointer Detection of several contaminants of emerging concern and with endocrine-disrupting activities Black-Right-Pointing-Pointer Phthalates are the dominant contaminant group with concentrations that are comparable with other countries.

  8. Solid waste deposits as a significant source of contaminants of emerging concern to the aquatic and terrestrial environments — A developing country case study from Owerri, Nigeria

    International Nuclear Information System (INIS)

    of isomers), metabolites of non-ionic surfactants (nonylphenol-polyethoxylates), UV-filter compound ethyl methoxy cinnamate (EHMC) and bisphenol A (BPA) were particularly determined in the sediment samples at high μg/kg dry weight concentration. Measuring contaminants in such areas will help in increasing governmental, societal and industrial awareness on the extent and seriousness of the contamination both at waste disposal sites and surrounding terrestrial and aquatic environments. -- Highlights: ► Solid waste management in developing countries ► Solid waste as a significant source of contaminants of emerging concern ► Contaminant leaching from solid waste to surrounding environment ► Detection of several contaminants of emerging concern and with endocrine-disrupting activities ► Phthalates are the dominant contaminant group with concentrations that are comparable with other countries.

  9. Are in vitro methods for the detection of endocrine potentials in the aquatic environment predictive for in vivo effects? Outcomes of the Projects SchussenAktiv and SchussenAktivplus in the Lake Constance Area, Germany.

    Directory of Open Access Journals (Sweden)

    Anja Henneberg

    Full Text Available Many studies about endocrine pollution in the aquatic environment reveal changes in the reproduction system of biota. We analysed endocrine activities in two rivers in Southern Germany using three approaches: (1 chemical analyses, (2 in vitro bioassays, and (3 in vivo investigations in fish and snails. Chemical analyses were based on gas chromatography coupled with mass spectrometry. For in vitro analyses of endocrine potentials in water, sediment, and waste water samples, we used the E-screen assay (human breast cancer cells MCF-7 and reporter gene assays (human cell line HeLa-9903 and MDA-kb2. In addition, we performed reproduction tests with the freshwater mudsnail Potamopyrgus antipodarum to analyse water and sediment samples. We exposed juvenile brown trout (Salmo trutta f. fario to water downstream of a wastewater outfall (Schussen River or to water from a reference site (Argen River to investigate the vitellogenin production. Furthermore, two feral fish species, chub (Leuciscus cephalus and spirlin (Alburnoides bipunctatus, were caught in both rivers to determine their gonadal maturity and the gonadosomatic index. Chemical analyses provided only little information about endocrine active substances, whereas the in vitro assays revealed endocrine potentials in most of the samples. In addition to endocrine potentials, we also observed toxic potentials (E-screen/reproduction test in waste water samples, which could interfere with and camouflage endocrine effects. The results of our in vivo tests were mostly in line with the results of the in vitro assays and revealed a consistent reproduction-disrupting (reproduction tests and an occasional endocrine action (vitellogenin levels in both investigated rivers, with more pronounced effects for the Schussen river (e.g. a lower gonadosomatic index. We were able to show that biological in vitro assays for endocrine potentials in natural stream water reasonably reflect reproduction and endocrine

  10. Chapter 5. Assessing the Aquatic Hazards of Veterinary Medicines

    Science.gov (United States)

    In recent years, there has been increasing awareness of the widespread distribution of low concentrations of veterinary medicine products and other pharmaceuticals in the aquatic environment. While aquatic hazard for a select group of veterinary medicines has received previous s...

  11. Adaptations in the structure and innervation of follicle-sinus complexes to an aquatic environment as seen in the Florida manatee (Trichechus manatus latirostris).

    Science.gov (United States)

    Sarko, Diana K; Reep, Roger L; Mazurkiewicz, Joseph E; Rice, Frank L

    2007-09-20

    Florida manatees are large-bodied aquatic herbivores that use large tactile vibrissae for several purposes. Facial vibrissae are used to forage in a turbid water environment, and the largest perioral vibrissae can also grasp and manipulate objects. Other vibrissae distributed over the entire postfacial body appear to function as a lateral line system. All manatee vibrissae emanate from densely innervated follicle-sinus complexes (FSCs) like those in other mammals, although proportionately larger commensurate with the caliber of the vibrissae. As revealed by immunofluorescence, all manatee FSCs have many types of C, Adelta and Abeta innervation including Merkel, club, and longitudinal lanceolate endings at the level of the ring sinus, but they lack other types such as reticular and spiny endings at the level of the cavernous sinus. As in non-whisking terrestrial species, the inner conical bodies of facial FSCs are well innervated but lack Abeta-fiber terminals. Importantly, manatee FSCs have two unique types of Abeta-fiber endings. First, all of the FSCs have exceptionally large-caliber axons that branch to terminate as novel, gigantic spindle-like endings located at the upper ring sinus. Second, facial FSCs have smaller caliber Abeta fibers that terminate in the trabeculae of the cavernous sinus as an ending that resembles a Golgi tendon organ. In addition, the largest perioral vibrissae, which are used for grasping, have exceptionally well-developed medullary cores that have a structure and dense small-fiber innervation resembling that of tooth pulp. Other features of the epidermis and upper dermis structure and innervation differ from that seen in terrestrial mammals. PMID:17640045

  12. Nanoplastics in the aquatic environment

    NARCIS (Netherlands)

    Koelmans, A.A.; Besseling, E.; Shim, W.J.

    2015-01-01

    A growing body of literature reports on the abundance and effects of plastic debris, with an increasing focus on microplastic particles smaller than 5 mm. It has often been suggested that plastic particles in the

  13. Applications of molecular biology to understanding genotype-environment interactions in livestock production

    International Nuclear Information System (INIS)

    There is a continual consumer demand to increase the quality and total yield from livestock production systems. One way this can be achieved is to exploit the natural variation that exists within and across different animal breeds by selecting the genotypes that produce offspring well suited to a particular environment. In this context the environment may be the physical climate, the management system, nutritional level or perhaps disease and parasite loads. The genetic differences between animals may be reflected in measurable differences in performance in a given environment or in changes in the relative performance of genotypes in different environments. The basis of these genotype-environment interactions is the underlying genotype or combination of genes. New techniques in molecular biology allow the direct assessment and manipulation of animal genotypes using methods such as DNA marker analysis, sequencing, gene mapping and transgenesis. These techniques allow the identification, localization, analysis of interaction and alteration of individual genes, and in this way will greatly expand the understanding of genotype-environment interaction and help identify ways of optimizing animal breeding programmes. (author). 37 refs, 6 figs

  14. Nitric Oxide Diffusion Attributes in Biological And Artificial Environments: A Computational Study

    Directory of Open Access Journals (Sweden)

    Patricio García Báez

    2011-03-01

    Full Text Available This paper presents a computational study on the dynamic of nitric oxide (NO in both the biological and artificial environments, by means the analysis of important nitric oxide diffusion attributes, which are defined in this work. We apply the compartmental model of NO diffusion as a formal tool, using a computational neuroscience point of view. The main objective is the analyses of the emergence and dynamic of complex structures, essentially diffusion neighbourhood (DNB, in environments with volume transmission (VT. The study is performed by the observation of the NO diffusion attributes, the NO directionality (NOD, the average influence (AI and the center of DNB (CDNB. We present a study of the influences and dependences with respect to associated features to the NO synthesis-diffusion process, and to the different environments where it spreads (non-isotropy and non-homogeneity. The paper is structured into three sets of experiences which cover the aforementioned aspects: influence of the NO synthesis process, isolated and multiple processes, influence of distance to the element where NO is synthesized, and influence of features of the diffusion environment. The developments have been performed in mono bi-and three-dimensional environments, with endothelial cell features. The study contributes the needed formalism to management the dynamic of NO in artificial an biological environments also to quantify the information representation capacity that a type of NO diffusion-based signaling presents and their implications in many other underlying neural mechanisms, such as neural recruitment, synchronization of computations between neurons and in the brain activity in general.

  15. Solid waste deposits as a significant source of contaminants of emerging concern to the aquatic and terrestrial environments - a developing country case study from Owerri, Nigeria.

    Science.gov (United States)

    Arukwe, Augustine; Eggen, Trine; Möder, Monika

    2012-11-01

    isomers), metabolites of non-ionic surfactants (nonylphenol-polyethoxylates), UV-filter compound ethyl methoxy cinnamate (EHMC) and bisphenol A (BPA) were particularly determined in the sediment samples at high μg/kg dry weight concentration. Measuring contaminants in such areas will help in increasing governmental, societal and industrial awareness on the extent and seriousness of the contamination both at waste disposal sites and surrounding terrestrial and aquatic environments. PMID:22975307

  16. Sensor Fusion and Autonomy as a Powerful Combination for Biological Assessment in the Marine Environment

    Directory of Open Access Journals (Sweden)

    Mark A. Moline

    2016-02-01

    Full Text Available The ocean environment and the physical and biological processes that govern dynamics are complex. Sampling the ocean to better understand these processes is difficult given the temporal and spatial domains and sampling tools available. Biological systems are especially difficult as organisms possess behavior, operate at horizontal scales smaller than traditional shipboard sampling allows, and are often disturbed by the sampling platforms themselves. Sensors that measure biological processes have also generally not kept pace with the development of physical counterparts as their requirements are as complex as the target organisms. Here, we attempt to address this challenge by advocating the need for sensor-platform combinations to integrate and process data in real-time and develop data products that are useful in increasing sampling efficiencies. Too often, the data of interest is only garnered after post-processing after a sampling effort and the opportunity to use that information to guide sampling is lost. Here we demonstrate a new autonomous platform, where data are collected, analyzed, and data products are output in real-time to inform autonomous decision-making. This integrated capability allows for enhanced and informed sampling towards improving our understanding of the marine environment.

  17. BioGraphE: high-performance bionetwork analysis using the Biological Graph Environment

    Directory of Open Access Journals (Sweden)

    Sofia Heidi J

    2008-05-01

    Full Text Available Abstract Background Graphs and networks are common analysis representations for biological systems. Many traditional graph algorithms such as k-clique, k-coloring, and subgraph matching have great potential as analysis techniques for newly available data in biology. Yet, as the amount of genomic and bionetwork information rapidly grows, scientists need advanced new computational strategies and tools for dealing with the complexities of the bionetwork analysis and the volume of the data. Results We introduce a computational framework for graph analysis called the Biological Graph Environment (BioGraphE, which provides a general, scalable integration platform for connecting graph problems in biology to optimized computational solvers and high-performance systems. This framework enables biology researchers and computational scientists to identify and deploy network analysis applications and to easily connect them to efficient and powerful computational software and hardware that are specifically designed and tuned to solve complex graph problems. In our particular application of BioGraphE to support network analysis in genome biology, we investigate the use of a Boolean satisfiability solver known as Survey Propagation as a core computational solver executing on standard high-performance parallel systems, as well as multi-threaded architectures. Conclusion In our application of BioGraphE to conduct bionetwork analysis of homology networks, we found that BioGraphE and a custom, parallel implementation of the Survey Propagation SAT solver were capable of solving very large bionetwork problems at high rates of execution on different high-performance computing platforms.

  18. Influence of the operational environment on biological firmness of building composites

    Directory of Open Access Journals (Sweden)

    V.T. Erofeev

    2012-11-01

    Full Text Available In modern conditions durability and reliability of buildings are demanded more and more. According to it the special attention starts to be given to the danger of biological degradation of materials and constructions.Microorganisms are capable to occupy the surfaces of all tested kinds of widely used binding agents. However, the specific and quantitative compositions of microorganisms are various under identical service conditions.Having compared the quantity of kinds and types of the fungi developing on the samples of binders, it is possible to evaluate the efficiency of application of those or other building composites and to choose the most suitable materials for corresponding service conditions. It was experimentally shown that composites on a basis of alkaline glass binding agents possess the raised stability in the biologically corrosive environment.

  19. Toprak Kirlenmesi ve Biyolojik Çevre / Soil Pollution and Biological Environment

    OpenAIRE

    Kızıloğlu Algan, F. Tülay; Bilen, Serdar

    2011-01-01

    ÖZET: İnsanların yanlış uygulamaları sonucunda toprak ekosisteminin fiziksel, kimyasal ve biyolojik özellikleri arasındaki dengebozulmaktadır. Bu durum, toprak üzerinde ve içerisinde yaşayan canlıları (biyolojik çevre) olumsuz etkilemektedir. Bu makalede toprakkirliliği ile biyolojik çevre arasındaki etkileşimler özetlenmiştir.Anahtar Kelimeler: Toprak kirliliği, Biyolojik çevreSoil Pollution and Biological Environment ABSTRACT: In result f...

  20. Microorganisms isolated from subsurface environments and their importance for astrobiology and theoretical biology

    Directory of Open Access Journals (Sweden)

    Sergiu Fendrihan

    2010-07-01

    Full Text Available Objective: the article is a review of the very controversial microbial life in subsurfaceenvironments like caves, rocks, mines, deep subsurface water and springs, in very special extremeenvironments. Material and Methods: the methods of isolation of the bacteria and archaea fromsubsurface environments are discussed too and analysed. Results: the results of years of investigationsshowed the possiblilities of adaptation to extreme environments and survival on very long periods oftimes, even geological eras, of some microorganisms. The inner biochemical, physical, biological andenergetic mechanisms are still not elucidated, even some features were discovered. Conclusion: anextensive and intensive work of cooperation in this field of activity is required to discover themechanisms of long term survival in extreme conditions of the subsurface microorganisms.

  1. Predation by Asian bullfrog tadpoles, Hoplobatrachus tigerinus, against the dengue vector, Aedes aegypti, in an aquatic environment treated with mosquitocidal nanoparticles.

    Science.gov (United States)

    Murugan, Kadarkarai; Priyanka, Vishwanathan; Dinesh, Devakumar; Madhiyazhagan, Pari; Panneerselvam, Chellasamy; Subramaniam, Jayapal; Suresh, Udaiyan; Chandramohan, Balamurugan; Roni, Mathath; Nicoletti, Marcello; Alarfaj, Abdullah A; Higuchi, Akon; Munusamy, Murugan A; Khater, Hanem F; Messing, Russell H; Benelli, Giovanni

    2015-10-01

    Aedes aegypti is a primary vector of dengue and chikungunya. The use of synthetic insecticides to control Aedes populations often leads to high operational costs and adverse non-target effects. Botanical extracts have been proposed for rapid extracellular synthesis of mosquitocidal nanoparticles, but their impact against predators of mosquito larvae has not been well studied. We propose a single-step method for the biosynthesis of silver nanoparticles (AgNP) using the extract of Artemisia vulgaris leaves as a reducing and stabilizing agent. AgNP were characterized by UV-vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). SEM and XRD showed that AgNP were polydispersed, crystalline, irregularly shaped, with a mean size of 30-70 nm. EDX confirmed the presence of elemental silver. FTIR highlighted that the functional groups from plant metabolites capped AgNP, stabilizing them over time. We investigated the mosquitocidal properties of A. vulgaris leaf extract and green-synthesized AgNP against larvae and pupae of Ae. aegypti. We also evaluated the predatory efficiency of Asian bullfrog tadpoles, Hoplobatrachus tigerinus, against larvae of Ae. aegypti, under laboratory conditions and in an aquatic environment treated with ultra-low doses of AgNP. AgNP were highly toxic to Ae. aegypti larval instars (I-IV) and pupae, with LC50 ranging from 4.4 (I) to 13.1 ppm (pupae). In the lab, the mean number of prey consumed per tadpole per day was 29.0 (I), 26.0 (II), 21.4 (III), and 16.7 (IV). After treatment with AgNP, the mean number of mosquito prey per tadpole per day increased to 34.2 (I), 32.4 (II), 27.4 (III), and 22.6 (IV). Overall, this study highlights the importance of a synergistic approach based on biocontrol agents and botanical nano-insecticides for mosquito control. PMID:26091763

  2. Technical progress report of biological research on the volcanic island, Surtsey, and environment for the year 1975

    Energy Technology Data Exchange (ETDEWEB)

    Fridriksson, S.

    1975-01-01

    The study involves terrestrial biological research on the volcanic island, Surtsey, off the coast of Iceland and the neighboring islands and environs of the Westman Islands, which are situated on the mid-Atlantic Ridge.

  3. Studies on the aquatic environment at Olkiluoto and reference area. 1: Olkiluoto, reference lakes and Eurajoki and Lapijoki rivers in 2009-2010

    International Nuclear Information System (INIS)

    This working report presents the first results of a sampling campaign at Olkiluoto and reference lakes and rivers selected to resemble the aquatic systems expected to form at the site in the future with the post-glacial crustal rebound (land uplift). In 2009-2010, the aim of the studies was to improve the knowledge of the aquatic systems and to produce input data to the safety case for the spent nuclear fuel repository at Olkiluoto. The first main objective was to estimate the areal biomass distribution and measure the dimensions of characteristic aquatic plants and animals. Another objective was to estimate the transfer of different elements from water to the aquatic organisms paying special attention on key elements (Ag, Cl, I, Mo, Nb and Se) in the dose assessment within the safety case. Surface water, sediment, macrophyte, fish and macrobenthos samples were collected from the Olkiluoto coastal area and from the reference lakes for biomass and dimension measurements and analysis of element concentration. Water-to-biota concentration ratios were estimated for the coastal area and for the reference lakes. From rivers, only water samples were collected at this stage. In 2009-2010, sampling procedures and pre-treatment methods were developed and analytical methods were optimised. Thus, the results reported here are indicative by their nature. After 2010, the studies have been continued with better established methods, and the more recent results will be reported later. (orig.)

  4. Studies on the aquatic environment at Olkiluoto and reference area. 1: Olkiluoto, reference lakes and Eurajoki and Lapijoki rivers in 2009-2010

    Energy Technology Data Exchange (ETDEWEB)

    Kangasniemi, V. [Environmental Research and Assessment EnviroCase Ltd., Pori (Finland); Helin, J.

    2014-03-15

    This working report presents the first results of a sampling campaign at Olkiluoto and reference lakes and rivers selected to resemble the aquatic systems expected to form at the site in the future with the post-glacial crustal rebound (land uplift). In 2009-2010, the aim of the studies was to improve the knowledge of the aquatic systems and to produce input data to the safety case for the spent nuclear fuel repository at Olkiluoto. The first main objective was to estimate the areal biomass distribution and measure the dimensions of characteristic aquatic plants and animals. Another objective was to estimate the transfer of different elements from water to the aquatic organisms paying special attention on key elements (Ag, Cl, I, Mo, Nb and Se) in the dose assessment within the safety case. Surface water, sediment, macrophyte, fish and macrobenthos samples were collected from the Olkiluoto coastal area and from the reference lakes for biomass and dimension measurements and analysis of element concentration. Water-to-biota concentration ratios were estimated for the coastal area and for the reference lakes. From rivers, only water samples were collected at this stage. In 2009-2010, sampling procedures and pre-treatment methods were developed and analytical methods were optimised. Thus, the results reported here are indicative by their nature. After 2010, the studies have been continued with better established methods, and the more recent results will be reported later. (orig.)

  5. Physical-chemical characterization of nanoparticles in relevant biological environments and their interactions with the cell surface

    OpenAIRE

    Di Silvio, Desire

    2015-01-01

    Nanoparticles (NPs) are versatile tools for nanomedicine and tuning features such as material, size and charge, imaging and targeting can be accomplished. However, NPs behaviour in vivo is modified upon interaction with the biological matter and formation of a protein corona (PC) coating the NP. The PC determines the NP biological identity and it is the ultimate interface with the surrounding environment. Therefore, a deep characterization of the NPs in biological media is important to predic...

  6. Lilienfeld Prize Talk: New Results on Water in Bulk, Nanoconfined, and Biological Environments

    Science.gov (United States)

    Stanley, H. Eugene

    2008-04-01

    This talk will introduce some of the 63 unsolved mysteries of water, and will demonstrate some recent progress in solving them combining information provided by water in bulk, nanoconfined, and biological environments. In particular, we will present evidence from experiments designed to test the hypothesis that water displays ``polymorphism'' in that it can exist in two liquid different phases and display a novel liquid-liquid critical point. The concept of liquid polymorphism is also proving useful in understanding some of the anomalies of other liquids with local tetrahedral symmetry, such as silicon, silica, and carbon. In particular, the talk will discuss changes in dynamic transport properties [1], and water in biological environments, including a possible physical explanation for the phenomenon known as the protein glass transition [2]. [1] P. Kumar, S. V. Buldyrev, S. L. Becker, P. H. Poole, F. W. Starr, and H. E. Stanley, ``Relation between the Widom line and the Breakdown of the Stokes--Einstein Relation in Supercooled Water,'' Proc. Natl. Acad. Sci. USA 104, 9575-9579 (2007). [2] P. Kumar, Z. Yan, L. Xu, M. G. Mazza, S. V. Buldyrev, S.-H. Chen. S. Sastry, and H. E. Stanley, ``Glass Transition in Biomolecules and the Liquid-Liquid Critical Point of Water,'' Phys. Rev. Lett. 97, 177802 (2006).

  7. A Novel CPU/GPU Simulation Environment for Large-Scale Biologically-Realistic Neural Modeling

    Directory of Open Access Journals (Sweden)

    Roger V Hoang

    2013-10-01

    Full Text Available Computational Neuroscience is an emerging field that provides unique opportunities to studycomplex brain structures through realistic neural simulations. However, as biological details are added tomodels, the execution time for the simulation becomes longer. Graphics Processing Units (GPUs are now being utilized to accelerate simulations due to their ability to perform computations in parallel. As such, they haveshown significant improvement in execution time compared to Central Processing Units (CPUs. Most neural simulators utilize either multiple CPUs or a single GPU for better performance, but still show limitations in execution time when biological details are not sacrificed. Therefore, we present a novel CPU/GPU simulation environment for large-scale biological networks,the NeoCortical Simulator version 6 (NCS6. NCS6 is a free, open-source, parallelizable, and scalable simula-tor, designed to run on clusters of multiple machines, potentially with high performance computing devicesin each of them. It has built-in leaky-integrate-and-fire (LIF and Izhikevich (IZH neuron models, but usersalso have the capability to design their own plug-in interface for different neuron types as desired. NCS6is currently able to simulate one million cells and 100 million synapses in quasi real time by distributing dataacross these heterogeneous clusters of CPUs and GPUs.

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

    Science.gov (United States)

    Schaumann, Gabriele E; Philippe, Allan; Bundschuh, Mirco; Metreveli, George; Klitzke, Sondra; Rakcheev, Denis; Grün, Alexandra; Kumahor, Samuel K; Kühn, Melanie; Baumann, Thomas; Lang, Friederike; Manz, Werner; Schulz, Ralf; Vogel, Hans-Jörg

    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 TiO2 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 Ag2S 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 TiO2 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 TiO2 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 EINP in

  9. Study the Effectiveness of Technology-Enhanced Interactive Teaching Environment on Student Learning of Junior High School Biology

    Science.gov (United States)

    Yang, Kai-Ti; Wang, Tzu-Hua; Chiu, Mei-Hung

    2015-01-01

    This research investigates the effectiveness of integrating Interactive Whiteboard (IWB) into the junior high school biology teaching. This research adopts a quasi-experimental design and divides the participating students into the conventional ICT-integrated learning environment and IWB-integrated learning environment. Before teaching, students…

  10. Effects of Web Based Inquiry Science Environment on Cognitive Outcomes in Biological Science in Correlation to Emotional Intelligence

    Science.gov (United States)

    Manoj, T. I.; Devanathan, S.

    2010-01-01

    This research study is the report of an experiment conducted to find out the effects of web based inquiry science environment on cognitive outcomes in Biological science in correlation to Emotional intelligence. Web based inquiry science environment (WISE) provides a platform for creating inquiry-based science projects for students to work…

  11. Production in aquatic macrophyte communities

    DEFF Research Database (Denmark)

    Binzer, Thomas; Sand-Jensen, Kaj

    2002-01-01

    combined a simple mechanistic model and empirical measurements on artificially structured macroalgal communities (Ulva lactuca) with varying thallus absorptance and community density. Predicted and measured values corresponded closely and revealed that gross production in high-light environments...... that inefficient distribution of light can account for the low community production rates in aquatic habitats and the depth distribution of form-functional groups of macroalgae with different canopy structure.......-dimensional structure because of the strong drag and shear forces of moving water. This difference in canopy structure has been suggested to account for the three- to fivefold higher gross production rates in terrestrial than aquatic communities. To evaluate the effect of community structure in aquatic habitats, we...

  12. Simultaneous trace analysis of organic arsenic and antimony compounds in an aquatic environment using HPLC/ICP-MS; Simultane Spurenanalytik arsen- und antimonorganischer Verbindungen in der aquatischen Umwelt mittels HPLC/ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Drescher, C.

    2000-07-01

    A method for simultaneous element species analysis of organometallic and inorganic compounds by direct coupling of HPLC and ICP-MS was used for the first time for analyses or arsenic and antimony compounds in an aquatic environment. [German] In der vorliegenden Arbeit wurde erstmalig eine Methode zur simultanen Elementspeziesanalytik metallorganischer und anorganischer Verbindungen mittels direkter Kopplung von HPLC und ICP-MS entwickelt und zur Untersuchung von Arsen und Antimonverbindungen in der aquatischen Umwelt eingesetzt. Ziel der Arbeiten war es, das Potential fluessigkeitschromatographischer Trennmethoden als Basis von Kopplungsmethoden zur simultanen Multielement-Speziesanalytik zu beschreiben und deren Leistungsfaehigkeit im Vergleich mit etablierten Methoden zu bewerten. (orig.)

  13. Caloric density of aquatic macrophytes in different environments of the Baía river subsystem, upper Paraná river floodplain, Brazil

    Directory of Open Access Journals (Sweden)

    Célia de Almeida Lopes

    2006-09-01

    Full Text Available The aim of this work was to determine the caloric density of leaves, stems and roots of aquatic macrophytes in different environments of the Baía subsystem (Baía river and Fechada and Guaraná lagoons on the Upper Paraná river floodplain, in addition to identify the variability between ecological groups. Samplings of Eichhornia crassipes, Salvinia spp, Pistia stratiotes, Eichhornia azurea, Polygonum sp, Cyperaceae and Poaceae were carried out in February 2003. Spatial differences in the caloric densities were not observed for these plants. Caloric density values varied from 1906.9 cal/g dry weight (root to 4675.0 cal/g dry weight (leaf. However, significant differences between the caloric content averages of the vegetative structures were observed only for Polygonum sp and Salvinia spp. In relation to the ecological groups, the highest average value was verified for the emergent macrophytes (3529.7 ± 722.5, which were significantly different from the floating ones (3056.5 ± 571.0. There was no difference between the sites included in the subsystem when the caloric densities were compared.O presente trabalho teve por objetivo determinar a densidade calórica de folhas, caules e raízes de macrófitas aquáticas, em diferentes ambientes do subsistema Baía (Rio Baía e lagoas Fechada e do Guaraná na planície de inundação do alto rio Paraná, além de identificar a variabilidade entre grupos ecológicos. As amostragens foram realizadas em fevereiro de 2003, sendo coletadas amostras de diferentes macrófitas, Eichhornia crassipes, Salvinia spp, Pistia stratiotes, Eichhornia azurea, Polygonum sp, Cyperaceae e Poaceae. Diferenças espaciais nas densidades calóricas não foram observadas para as plantas estudadas. Os valores de densidade calórica variaram de 1906,9 cal/g de peso seco (raiz a 4675,0 cal/g de peso seco (folha. Entretanto, diferenças significativas entre as médias dos conteúdos calóricos das estruturas vegetativas foram

  14. The effect of deposition electrolyte on polypyrrole surface interaction with biological environment

    Science.gov (United States)

    Mîndroiu, Mihaela; Ungureanu, Camelia; Ion, Raluca; Pîrvu, Cristian

    2013-07-01

    The effects of electrolyte type used in electrodeposition of polypyrrole (PPy) films on Ti6Al7Nb alloy was studied in order to design a titanium modified surface with enhanced antibacterial activity and better biocompatibility. Therefore, the polypyrrole coatings were synthesized by potentiostatic electrochemically technique from pyrrole and lithium perchlorate (LiClO4) using aqueous and non-aqueous solutions. The both PPy films were characterized by electrochemical methods in Hank's Balanced Salt Solution (HBSS), and surface characterization by Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) analysis, adhesion test and contact angle measurements. A correlation between the film stability and surface properties, synthesis parameters and the interaction with biological environment was established. The physical-chemical properties of the studied PPy films are in direct related with the doping level and have an important influence of the biocompatibility and antibacterial activity.

  15. The effect of deposition electrolyte on polypyrrole surface interaction with biological environment

    International Nuclear Information System (INIS)

    The effects of electrolyte type used in electrodeposition of polypyrrole (PPy) films on Ti6Al7Nb alloy was studied in order to design a titanium modified surface with enhanced antibacterial activity and better biocompatibility. Therefore, the polypyrrole coatings were synthesized by potentiostatic electrochemically technique from pyrrole and lithium perchlorate (LiClO4) using aqueous and non-aqueous solutions. The both PPy films were characterized by electrochemical methods in Hank's Balanced Salt Solution (HBSS), and surface characterization by Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) analysis, adhesion test and contact angle measurements. A correlation between the film stability and surface properties, synthesis parameters and the interaction with biological environment was established. The physical-chemical properties of the studied PPy films are in direct related with the doping level and have an important influence of the biocompatibility and antibacterial activity.

  16. Nitrous oxide emission by aquatic macrofauna

    Science.gov (United States)

    Stief, Peter; Poulsen, Morten; Nielsen, Lars Peter; Brix, Hans; Schramm, Andreas

    2009-01-01

    A large variety of aquatic animals was found to emit the potent greenhouse gas nitrous oxide when nitrate was present in the environment. The emission was ascribed to denitrification by ingested bacteria in the anoxic animal gut, and the exceptionally high N2O-to-N2 production ratio suggested delayed induction of the last step of denitrification. Filter- and deposit-feeding animal species showed the highest rates of nitrous oxide emission and predators the lowest, probably reflecting the different amounts of denitrifying bacteria in the diet. We estimate that nitrous oxide emission by aquatic animals is quantitatively important in nitrate-rich aquatic environments like freshwater, coastal marine, and deep-sea ecosystems. The contribution of this source to overall nitrous oxide emission from aquatic environments might further increase because of the projected increase of nitrate availability in tropical regions and the numeric dominance of filter- and deposit-feeders in eutrophic ecosystems. PMID:19255427

  17. Degradation of biological weapons agents in the environment: implications for terrorism response.

    Science.gov (United States)

    Stuart, Amy L; Wilkening, Dean A

    2005-04-15

    We investigate the impact on effective terrorism response of the viability degradation of biological weapons agents in the environment. We briefly review the scientific understanding and modeling of agent environmental viability degradation. In general, agent susceptibility to viability loss is greatest for vegetative bacteria, intermediate for viruses, and least for bacterial spores. Survival is greatest in soil and progressively decreases in the following environments: textiles, water, hard surfaces, and air. There is little detailed understanding of loss mechanisms. We analyze the time behavior and sensitivity of four mathematical models that are used to represent environmental viability degradation (the exponential, probability, and first- and second-order catastrophic decay models). The models behave similarly at short times (representation of the hazard. For longer time phenomena, including decontamination, the current model capabilities are likely insufficient. Finally, we implement each model in a simple numerical integration of anthrax dispersion, viability degradation, and dose response. Decay models spanning the current knowledge of airborne degradation result in vastly different predicted hazard areas. This confounds attempts to determine necessary medical and decontamination measures. Hence,the current level of understanding and representation of environmental viability degradation in response models is inadequate to inform appropriate emergency response measures. PMID:15884371

  18. Reactivity of inorganic nanoparticles in biological environments: insights into nanotoxicity mechanisms

    International Nuclear Information System (INIS)

    A deeper understanding of the behaviour of inorganic nanoparticles in biological media is needed not only to fully control and develop the potential of these materials but also to increase knowledge of the physical chemistry of inorganic materials when their morphology approaches that of molecular entities. Although this knowledge and control is not yet entirely acquired, industry and society are already using nanomaterials in greater quantities and in consumer products. As normally happens when something new arrives in society, the interest in the broader implications of this emerging technology has grown together with unfounded ‘nanoeuphoria’ and ‘nanoscares’. In this context, only by understanding the mechanisms of the nano-bio interaction will it be possible to safely develop nanotechnology. In this review, we discuss on how nanoparticles behave once they are naturally or intentionally produced and are exposed to humans and the environment. The response of nanoparticles inside organisms or released to the environment is complex and diverse, and depends on a variety of parameters involved. Mainly, they may (i) be aggregated into microscopic particles or embedded in exposed materials; (ii) the surfaces of the nanoparticles, which determine their bioactivity, experience constant modifications; and (iii) nanoparticles may corrode and dissolve or they can suffer morphological modifications.

  19. Acute toxicity assessment of Osthol content in bio-pesticides using two aquatic organisms

    OpenAIRE

    Yim, Eun-Chae; Kim, Hyeon Joe; Kim, Seong-Jun

    2014-01-01

    Objectives This study focused on the assessment of acute toxicity caused by Osthol, a major component of environment-friendly biological pesticides, by using two aquatic organisms. Methods The assessment of acute toxicity caused by Osthol was conducted in Daphnia magna and by examining the morphological abnormalities in Danio rerio embryos. Results The median effective concentration value of Osthol in D. magna 48 hours after inoculation was 19.3 μM. The median lethal concentration of D. rerio...

  20. Ecotoxicological effects of selected engineered nano-materials to aquatic organisms in relation to their physicochemicalcharacteristics

    OpenAIRE

    Wong, Wing-yu.; 黃詠如.

    2011-01-01

    Engineered nanomaterials (NMs), defined as artificially made particles possessing at least one dimension within 1 – 100 nm range, have different physical and biological properties from bulk materials of the same chemistry due to their increased surface areas. Their novel properties have facilitated the prolific growth of commercial NM-incorporating products. NMs may be leached into the aquatic environment during the product life-cycle, but their ecological impacts on marine ecosystems are cu...

  1. The NEON Aquatic Network: Expanding the Availability of Biogeochemical Data

    Science.gov (United States)

    Vance, J. M.; Bohall, C.; Fitzgerald, M.; Utz, R.; Parker, S. M.; Roehm, C. L.; Goodman, K. J.; McLaughlin, B.

    2013-12-01

    Aquatic ecosystems are facing unprecedented pressure from climate change and land-use practices. Invasive species, whether plant, animal, insect or microbe present additional threat to aquatic ecosystem services. There are significant scientific challenges to understanding how these forces will interact to affect aquatic ecosystems, as the flow of energy and materials in the environment is driven by multivariate and non-linear biogeochemical cycles. The National Ecological Observatory Network (NEON) will collect and provide observational data across multiple scales. Sites were selected to maximize representation of major North American ecosystems using a multivariate geographic clustering method that partitioned the continental US, AK, HI, and Puerto Rico into 20 eco-climatic domains. The NEON data collection systems and methods are designed to yield standardized, near real-time data subjected to rigorous quality controls prior to public dissemination through an online data portal. NEON will collect data for 30 years to facilitate spatial-temporal analysis of environmental responses and drivers of ecosystem change, ranging from local through continental scales. Here we present the NEON Aquatic Network, a multi-parameter network consisting of a combination of in situ sensor and observational data. This network will provide data to examine biogeochemical, biological, hydrologic and geomorphic metrics at 36 sites, which are a combination of small 1st/2nd order wadeable streams, large rivers and lakes. A typical NEON Aquatic site will host up to two in-stream sensor sets designed to collect near-continuous water quality data (e.g. pH/ORP, temperature, conductivity, dissolved oxygen, CDOM) along with up to 8 shallow groundwater monitoring wells (level, temp., cond.), and a local meteorological station (e.g. 2D wind speed, PAR, barometric pressure, temperature, net radiation). These coupled sensor suites will be complemented by observational data (e.g. water

  2. Research unit INTERNANO: Mobility, aging and functioning of engineered inorganic nanoparticles at the aquatic-terrestrial interface

    Science.gov (United States)

    Schaumann, Gabriele Ellen; Metreveli, George; Baumann, Thomas; Klitzke, Sondra; Lang, Friederike; Manz, Werner; Nießner, Reinhard; Schulz, Ralf; Vogel, Hans-Jörg

    2013-04-01

    Engineered inorganic nanoparticles (EINP) are expected to pass the wastewater-river-topsoil-groundwater pathway. Despite their increasing release, the processes governing the EINP aging and the changes in functionality in the environment are up to now largely unknown. The objective of the interdisciplinary research unit INTERNANO funded by the DFG is to identify the processes relevant for the fate of EINP and EINP-associated pollutants in the interfacial zone between aquatic and terrestrial ecosystems. The research unit consists of six subprojects and combines knowledge from aquatic and terrestrial sciences as well as from microbiology, ecotoxicology, physicochemistry, soil chemistry and soil physics. For the identification of key processes we will consider compartment specific flow conditions, physicochemistry and biological activity. Situations representative for a floodplain system are simulated using micromodels (μm scale) as well as incubation, soil column and joint laboratory stream microcosm experiments. These results will be transferred to a joint aquatic-terrestrial model system on EINP aging, transport and functioning across the aquatic-terrestrial transition zone. EINP isolation and characterization will be carried out via a combination of chromatographic, light scattering and microscopic methods including dynamic light scattering, elemental analysis, hydrodynamic radius chromatography, field flow fractionation as well as atomic force microscopy, Raman microscopy and electron microscopy. INTERNANO generates fundamental aquatic-terrestrial process knowledge, which will help to evaluate the environmental significance of the EINP at aquatic-terrestrial interfaces. Thus, INTERNANO provides a scientific basis to assess and predict the environmental impact of EINP release into the environment.

  3. Merging Worlds of Nanomaterials and Biological Environment: Factors Governing Protein Corona Formation on Nanoparticles and Its Biological Consequences

    Science.gov (United States)

    Foroozandeh, Parisa; Aziz, Azlan Abdul

    2015-05-01

    Protein corona has became a prevalent subject in the field of nanomedicine owing to its diverse role in determining the efficiency, efficacy, and the ultimate biological fate of the nanomaterials used as a tool to treat and diagnose various diseases. For instance, protein corona formation on the surface of nanoparticles can modify its physicochemical properties and interfere with its intended functionalities in the biological microenvironments. As such, much emphasis should be placed in understanding these complex phenomena that occur at the bio-nano interface. The main aim of this review is to present different factors that are influencing protein-nanoparticle interaction such as physicochemical properties of nanoparticle ( i.e., size and size distribution, shape, composition, surface chemistry, and coatings) and the effect of biological microenvironments. Apart from that, the effect of ignored factors at the bio-nano interface such as temperature, plasma concentration, plasma gradient effect, administration route, and cell observer were also addressed.

  4. Quantitative Redox Biology: An approach to understanding the role of reactive species in defining the cellular redox environment

    OpenAIRE

    Buettner, Garry R.; Wagner, Brett A.; Victor G J Rodgers

    2013-01-01

    Systems biology is now recognized as a needed approach to understand the dynamics of inter- and intra-cellular processes. Redox processes are at the foundation of nearly all aspects of biology. Free radicals, related oxidants, and antioxidants are central to the basic functioning of cells and tissues. They set the cellular redox environment and therefore are key to regulation of biochemical pathways and networks, thereby influencing organism health. To understand how short-lived, quasi-stable...

  5. Aquatic impact

    International Nuclear Information System (INIS)

    Because of the high reproduction rates of the plankton and good tidal mixing at existing plants, depletion of plankton populations has not occurred. Spawning occurs throughout the Bay for the species of fish present here, so local depletions are insufficient to decrease Bay populations. Impingement totals are small compared to mortality due to other sources. In addition, efforts to reduce these totals are now underway at all three existing plants, Calvert Cliffs, Morgantown, and Chalk Point. Habitat modification effects, usually more subtle in nature, have minor, localized impacts. Coupled together, the power plant monitoring studies show a low cumulative impact on the mesohaline environment. The major area of concern within this region is the impact of cooling water withdrawals upon the nursery and spawning areas of striped bass and other anadromous species. Possum Point and Vienna have the highest potential for impact. New facilities planned for this region (Douglas Point, Summit, and Vienna) would increase withdrawals. The overall impact upon striped bass due to entrainment drops from an estimated 6.6% entrainment (upper bound) of the eggs and larvae spawned in the Maryland portion of the Bay at present to an estimated 3.4% (upper bound) after 1987. The addition of Douglas Point and Summit is more than off-set by the retirements of the once-through cooling units at Vienna. No impingement data are available at any of the present plants; however, degraded water quality at the Baltimore and Washington plants appears to have severely restricted fish populations in these waters. The proposed plants are expected to have no major impacts in the areas of impingement or habitat modification due to the small amount of water withdrawn

  6. Aquatic Organic Matter Fluorescence - from phenomenon to application

    Science.gov (United States)

    Reynolds, Darren

    2014-05-01

    The use of fluorescence to quantify and characterise aquatic organic matter in river, ocean, ground water and drinking and waste waters has come along way since its discovery as a phenomenon in the early 20th century. For example, there are over 100 papers published each year in international peer reviewed journals, an order of magnitude increase since a decade ago (see Figure taken from ISI database from 1989 to 2007 for publications in the fields of river water and waste water). Since then it has been extensively used as a research tool since the 1990's by scientists and is currently used for a wide variety of applications within a number of sectors. Universities, organisations and companies that research into aquatic organic matter have either recently readily use appropriate fluorescence based techniques and instrumentation. In industry and government, the technology is being taken up by environmental regulators and water and wastewater companies. This keynote presentation will give an overview of aquatic organic matter fluorescence from its conception as a phenomenon through to its current use in a variety of emerging applications within the sectors concerned with understanding, managing and monitoring the aquatic environment. About the Speaker Darren Reynolds pioneered the use of fluorescence spectroscopy for the analysis of wastewaters in the 1990's. He currently leads a research group within the Centre for Research in Biosciences and sits on the Scientific Advisory Board for the Institute of Bio-Sensing Technology at the University of the West of England, Bristol. He is a multidisciplinary scientist concerned with the development of technology platforms for applications in the fields of environment/agri-food and health. His current research interests include the development of optical technologies and techniques for environmental and biological sensing and bio-prospecting applications. He is currently involved in the development and use of synthetic biology

  7. Biologically inspired crack delocalization in a high strain-rate environment.

    Science.gov (United States)

    Knipprath, Christian; Bond, Ian P; Trask, Richard S

    2012-04-01

    Biological materials possess unique and desirable energy-absorbing mechanisms and structural characteristics worthy of consideration by engineers. For example, high levels of energy dissipation at low strain rates via triggering of crack delocalization combined with interfacial hardening by platelet interlocking are observed in brittle materials such as nacre, the iridescent material in seashells. Such behaviours find no analogy in current engineering materials. The potential to mimic such toughening mechanisms on different length scales now exists, but the question concerning their suitability under dynamic loading conditions and whether these mechanisms retain their energy-absorbing potential is unclear. This paper investigates the kinematic behaviour of an 'engineered' nacre-like structure within a high strain-rate environment. A finite-element (FE) model was developed which incorporates the pertinent biological design features. A parametric study was carried out focusing on (i) the use of an overlapping discontinuous tile arrangement for crack delocalization and (ii) application of tile waviness (interfacial hardening) for improved post-damage behaviour. With respect to the material properties, the model allows the permutation and combination of a variety of different material datasets. The advantage of such a discontinuous material shows notable improvements in sustaining high strain-rate deformation relative to an equivalent continuous morphology. In the case of the continuous material, the shockwaves propagating through the material lead to localized failure while complex shockwave patterns are observed in the discontinuous flat tile arrangement, arising from platelet interlocking. The influence of the matrix properties on impact performance is investigated by varying the dominant material parameters. The results indicate a deceleration of the impactor velocity, thus delaying back face nodal displacement. A final series of FE models considered the

  8. 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)

    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 TiO2 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 Ag2S 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 TiO2 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 TiO2 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 EINP

  9. 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

  10. Report of the results of the fiscal 1997 regional consortium R and D project. Regional consortium field / Development of technology to treat aquatic environment by using microorganisms fixed on carbon fabrics (abbreviation: carbon/aquatic environment project) (first fiscal year); 1997 nendo chiiki consortium kenkyu kaihatsu jigyo. Chiiki consortium bun`ya / tanso sen`i nansoshiki eno biseibutsu kochaku gensho wo riyoshita mizukankyo seibi gijutsu no kaihatsu (ryakusho: tanso mizu kankyo project) daiichi nendo seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    Out of the development of technology to arrange the aquatic environment using phenomena of microorganism fixation on carbon fiber soft textures, the paper stated the fiscal 1997 result. On carbon fibers in a state of swaying in water, microorganisms in water fix in an amazingly large quantity. A catalog was compiled of 58 kinds of carbon fabrics trially woven and knitted. When carbon fiber is used as activated sludge carrier, activity of microorganism lasts more than one year. Only a little amount of surplus sludge is generated. The fixed microorganisms are more active in case of carbon fiber than in case of nylon and polyester fibers. Fiber texture models of carbon fiber fixing activated sludge groups were proposed. By pump operation, the water flow inside/outside microorganism groups is being accelerated. Several new strains of bacillus carboniphilus were isolated/identified from soil and marsh. To grasp relationships of characteristics among three elements such as the state of aquatic environment, fiber, and microorganism group, the experiment was prepared. Preliminary work is conducted to derive a simple equation for facility design, and experimental directions to obtain design conditions were proposed. 6 refs., 166 figs., 47 tabs.

  11. A summary of chemical and biological testing of proposed disposal of sediment from Richmond Harbor relative to the Deep Off-Shelf Reference Area, the Bay Farm Borrow Area, and the Alcatraz Environs Reference Area

    Energy Technology Data Exchange (ETDEWEB)

    Mayhew, H.L.; Karle, L.M.; Gruendell, B.D.; Pinza, M.R. [Battelle/Marine Sciences Lab., Sequim, WA (United States)

    1993-12-01

    The US Army Corps of Engineers was authorized to dredge Richmond Harbor to accomodate large, deep-draft vessels. An ecological evaluation of the Harbor sediments was performed describing the physical characteristics, toxic substances, effects on aquatic organisms,and potential for bioaccumulation of chemical contaminants. The objective of this report is to compare the sediment chemistry, acute toxicity, and bioaccumulation results of the Richmond Harbor sediments to each of the reference areas; i.e., the Deep Off-Shelf Reference Area, the Bay Farm Borrow Area, and the Alcatraz Environs Reference Area. This report will enable the US Army Corps of Engineers to determine whether disposal at a reference area is appropriate for all or part of the dredged material from Richmond Harbor. Chemical analyses were performed on 30 sediment samples; 28 of those samples were then combined to form 7 composites. The seven composites plus sediment from two additional stations received both chemical and biological evaluations.

  12. Pre-natal Aquatic Preparation

    OpenAIRE

    Frias, Ana; Serra, Célia

    2013-01-01

    Introduction: Water, a source of well-being, peace, fullness, freedom and harmony. For quite some time now, water is sought after for its renowned benefits in terms of relieving the physical and emotional changes which commonly occur during pregnancy. Objectives: 1) Describe the process of intervention, arising from the use of the aquatic environment in prenatal preparation 2) Relate the gains in health from prenatal preparation aquatica Method: Descriptive creating and applying a prep...

  13. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; preparation procedure for aquatic biological material determined for trace metals

    Science.gov (United States)

    Hoffman, Gerald L.

    1996-01-01

    A method for the chemical preparation of tissue samples that are subsequently analyzed for 22 trace metals is described. The tissue-preparation procedure was tested with three National Institute of Standards and Technology biological standard reference materials and two National Water Quality Laboratory homogenized biological materials. A low-temperature (85 degrees Celsius) nitric acid digestion followed by the careful addition of hydrogen peroxide (30-percent solution) is used to decompose the biological material. The solutions are evaporated to incipient dryness, reconstituted with 5 percent nitric acid, and filtered. After filtration the solutions were diluted to a known volume and analyzed by inductively coupled plasma-mass spectrometry (ICP-MS), inductively coupled plasma-atomic emission spectrometry (ICP-AES), and cold vapor-atomic absorption spectrophotometry (CV-AAS). Many of the metals were determined by both ICP-MS and ICP-AES. This report does not provide a detailed description of the instrumental procedures and conditions used with the three types of instrumentation for the quantitation of trace metals determined in this study. Statistical data regarding recovery, accuracy, and precision for individual trace metals determined in the biological material tested are summarized.

  14. Toward systems biology in brown algae to explore acclimation and adaptation to the shore environment.

    Science.gov (United States)

    Tonon, Thierry; Eveillard, Damien; Prigent, Sylvain; Bourdon, Jérémie; Potin, Philippe; Boyen, Catherine; Siegel, Anne

    2011-12-01

    Brown algae belong to a phylogenetic lineage distantly related to land plants and animals. They are almost exclusively found in the intertidal zone, a harsh and frequently changing environment where organisms are submitted to marine and terrestrial constraints. In relation with their unique evolutionary history and their habitat, they feature several peculiarities, including at the level of their primary and secondary metabolism. The establishment of Ectocarpus siliculosus as a model organism for brown algae has represented a framework in which several omics techniques have been developed, in particular, to study the response of these organisms to abiotic stresses. With the recent publication of medium to high throughput profiling data, it is now possible to envision integrating observations at the cellular scale to apply systems biology approaches. As a first step, we propose a protocol focusing on integrating heterogeneous knowledge gained on brown algal metabolism. The resulting abstraction of the system will then help understanding how brown algae cope with changes in abiotic parameters within their unique habitat, and to decipher some of the mechanisms underlying their (1) acclimation and (2) adaptation, respectively consequences of (1) the behavior or (2) the topology of the system resulting from the integrative approach. PMID:22136637

  15. Effect of Aquatic Immersion on Static Balance

    OpenAIRE

    Louder, Talin J.

    2013-01-01

    Objective To quantitatively assess measures of static balance and limits of stability (LOS) in an aquatic environment compared to on land. Methods Fifteen healthy, young adults (23 + or - 2 years) performed 90 s static balance trials on land and aquatic immersion at two different depths (greater trochanter, xiphoid process). Measures of 95% ellipse area and center of pressure (CoP) mean velocity were computed from the force data. Additionally, participants completed a visual analog scale (VAS...

  16. Ecotoxicological Assessment of Aquatic Genotoxicity Using the Comet Assay

    OpenAIRE

    KHUSNUL YAQIN

    2006-01-01

    Comet assay is a novel biological analysis, which is a sensitive, flexible, simple, rapid, and inexpensive method to assess aquatic genotoxicant. Since Singh and co-workers developed the method in 1988, its use has increased exponentially in various fields. This review discourses on the application of this assay in aquatic ecosystems. Various types of cells from various aquatic organisms have been tested by various genotoxicant both direct- and indirect-acting using the comet assay. The appli...

  17. Aquatic Models, Genomics and Chemical Risk Management§

    OpenAIRE

    Cheng, Keith C.; Hinton, David E.; Mattingly, Carolyn J.; Planchart, Antonio

    2011-01-01

    The 5th Aquatic Animal Models for Human Disease meeting follows four previous meetings (Hinton et al., 2009; Schmale et al., 2007; Schmale, 2004; Nairn et al., 2001) in which advances in aquatic animal models for human disease research were reported, and community discussion of future direction was pursued. At this meeting, discussion at a workshop entitled Bioinformatics and Computational Biology with Web-based Resources (20 September 2010) led to an important conclusion: Aquatic model resea...

  18. Proceedings of the 30. annual aquatic toxicity workshop

    International Nuclear Information System (INIS)

    This conference provided an opportunity for leaders in industry, governments and universities to exchange information and ideas on the current challenges and approaches to deal with aquatic toxicology and their biological effect on aquatic biota. The challenges range from dealing with the basics of aquatic toxicology to applications in environmental monitoring, regulation and guidelines, and the development of sediment and water quality criteria. The sessions were entitled as follows: (1) building a stronger bridge between laboratory and field, (2) de-mystifying mixtures, (3) environmental effects monitoring (EEM) in pulp and paper, (4) EEM in metal mining, (5) ecological risk assessment of metals in the environment, (6) exposure/effects and mechanistic models, (7) effects/impacts and ecological effects, (8) soil and sediment toxicity evaluation and current prospective practices, (9) source to tap, and tap to sewer, (10) management of effluents from municipal waste water treatment facilities in Canada, (11) fate and effects of pharmaceutical products, and, (12) fishy business in agriculture. The conference included 5 plenary sessions and 188 platform papers, of which 13 papers have been indexed separately for inclusion in the database. refs., tabs., figs

  19. Removal of pharmaceuticals and personal care products in aquatic plant-based systems: A review

    International Nuclear Information System (INIS)

    Pharmaceuticals and personal care products (PPCPs) in the aquatic environment are regarded as emerging contaminants and have attracted increasing concern. The use of aquatic plant-based systems such as constructed wetlands (CWs) for treatment of conventional pollutants has been well documented. However, available research studies on aquatic plant-based systems for PPCP removal are still limited. The removal of PPCPs in CWs often involves a diverse and complex set of physical, chemical and biological processes, which can be affected by the design and operational parameters selected for treatment. This review summarizes the PPCP removal performance in different aquatic plant-based systems. We also review the recent progress made towards a better understanding of the various mechanisms and pathways of PPCP attenuation during such phytoremediation. Additionally, the effect of key CW design characteristics and their interaction with the physico-chemical parameters that may influence the removal of PPCPs in functioning aquatic plant-based systems is discussed. -- Highlights: • Investigation of the removal performance of PPCPs in CW systems. • Investigation of the mechanisms and pathways contributing to PPCP removal in CWs. • Investigation of the effect of CW design parameters on PPCP removal. • Investigation of the correlation between physico-chemical parameters and PPCP removal. -- This review gives an overview of the present state of research on the removal of pharmaceutical and personal care products by means of constructed wetlands

  20. 人工纳米颗粒在水体中的行为及其对浮游植物的影响%Behaviors of Engineered Nanoparticles in Aquatic Environments and Impac ts on Marine Phytoplankton

    Institute of Scientific and Technical Information of China (English)

    李曼璐; 姜玥璐

    2015-01-01

    人工纳米颗粒( engineered nanoparticles,ENPs)因其特殊的尺寸效应及良好的光学﹑磁学等性质,已被广泛应用于医药﹑生物成像以及工业产品等领域。在生产﹑使用和排放的过程中,ENPs通过不同途径不可避免地进入水体,因此ENPs在水体中的行为和生物安全性也引起了人们的极大关注。在水生生态系统中,浮游植物作为初级生产者,为自身以及其他营养级生物提供营养物质﹑能量和氧气,因此受到ENPs的影响是难以估算的。近年来已有大量的研究证实ENPs对生物有毒性效应,但ENPs 进入浮游植物体内的机制以及ENPs在浮游植物体内的生物运输和转化的报道较少,并且这方面的机制仍不甚明确。本文重点介绍了纳米材料进入水体的途径,在水体中的行为以及对浮游植物的生物效应的最新研究进展,但这方面的机制研究需要进一步深入。%Engineered nanoparticles ( ENPs) have shown invaluable societal benefits and applications in drug targeting, biological imaging and industrial products. ENPs enter the water body through various paths during the processes of production, usage and emission, therefore the behavior and the biosafety of ENPs in water bodies have attracted increasing attention. As the primary producer of ecosystems, phytoplankton provide nutrients, energy and oxygen for both themselves and organisms at higher trophic levels in the aquatic ecosystems. These primary producers may be exposed to the biological and unpredictable effects of this emergent pollutant to the aquatic ecosystems. Numerous studies have proved the toxic effects of ENPs on phytoplankton, but the mechanisms of entry into the aquatic organisms as well as the stability, fate and biotransformation in phytoplankton still remain unclear. Here, we present a review of the pathways of ENPs entering the water, the subsequent behavior and biological effects of ENPs on phytoplankton with an emphasis on

  1. Biologic

    CERN Document Server

    Kauffman, L H

    2002-01-01

    In this paper we explore the boundary between biology and the study of formal systems (logic). In the end, we arrive at a summary formalism, a chapter in "boundary mathematics" where there are not only containers but also extainers ><, entities open to interaction and distinguishing the space that they are not. The boundary algebra of containers and extainers is to biologic what boolean algebra is to classical logic. We show how this formalism encompasses significant parts of the logic of DNA replication, the Dirac formalism for quantum mechanics, formalisms for protein folding and the basic structure of the Temperley Lieb algebra at the foundations of topological invariants of knots and links.

  2. Contaminação do ambiente aquático por pesticidas. Estudo de caso: águas usadas para consumo humano em Primavera do Leste, Mato Grosso - análise preliminar Aquatic environment contamination by pesticides. Case study: water used for human consumption in Primavera do Leste, Mato Grosso - preliminary analyses

    Directory of Open Access Journals (Sweden)

    Eliana Freire Gaspar de Carvalho Dores

    2001-02-01

    Full Text Available A preliminary analyses of the possible contamination of superficial and underground water by the active ingredients of the pesticide products used in the surroundings of the urban area of Primavera do Leste, Mato Grosso, Brazil, was carried out. A description of the study region and of its environmental characteristics, which can favor the contamination of the local aquatic environment, was presented. The EPA screening criteria, the groundwater ubiquity score (GUS and the criteria proposed by Goss were used to evaluate which pesticides might contaminate the local waters. Among the active ingredients studied, several present risks to the local aquatic environment.

  3. Spectroscopic properties of gold nanoparticles at the single-particle level in biological environments.

    Science.gov (United States)

    Estrada, Laura C; Gratton, Enrico

    2012-03-01

    Labeling cells and tissues with fluorescent probes, such as organic dyes and quantum dots (Qdots) is a widespread and successful technique for studying molecular dynamics both in vitro and in vivo. However, those probes usually suffer from undesirable photophysical/photochemical processes, such as blinking and photobleaching, limiting their utilization. The main challenges in fluorescent probe design are to improve their absorption/emission properties, and to provide higher stability against photobleaching. In the last few years, metallic nanoparticles (NPs) of various sizes, shapes, and compositions have been used as a new alternative for cellular microscopy. This is in part because-unlike common organic dyes and Qdots-metallic NPs do not bleach or blink upon continuous illumination, are extremely stable, very bright, and their luminescence spans over the visible spectrum. These characteristics make them attractive contrast agents for cell imaging both in vitro and in vivo. For these reasons, the emission of metallic NPs in bulk solutions has already been extensively characterized. In contrast with bulk experiments, where billions of molecules are measured simultaneously, single-particle techniques allow the observation of characteristics and dynamical processes otherwise hidden in the measured average. A full understanding of the photophysical properties of the NPs is critical when they are used for single-molecule applications. Photophysical processes can be a source of artifacts if they are not interpreted accordingly, and thus a careful characterization of these labels at the single-particle level became crucial for the correct interpretation of the experimental results. Herein, we study some of their unique optical properties at the single-particle level and show examples that illustrate their intrinsic heterogeneity when used in biological environments. PMID:22298327

  4. Lake Bathymetric Aquatic Vegetation

    Data.gov (United States)

    Minnesota Department of Natural Resources — Aquatic vegetation represented as polygon features, coded with vegetation type (emergent, submergent, etc.) and field survey date. Polygons were digitized from...

  5. Remaining Sites Verification Package for the 100-F-33, 146-F Aquatic Biology Fish Ponds, Waste Site Reclassification Form 2006-021

    Energy Technology Data Exchange (ETDEWEB)

    L. M. Dittmer

    2006-08-25

    The 100-F-33, 146-F Aquatice Biology Fish Ponds waste site was an area with six small rectangular ponds and one large circular pond used to conduct tests on fish using various mixtures of river and reactor effluent water. The current site conditions achieve the remedial action objectives specified in the Remaining Sites ROD. The results of verification and applicable confirmatory sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.

  6. Remaining Sites Verification Package for the 100-F-33, 146-F Aquatic Biology Fish Ponds. Attachment to Waste Site Reclassification Form 2006-021

    International Nuclear Information System (INIS)

    The 100-F-33, 146-F Aquatice Biology Fish Ponds waste site was an area with six small rectangular ponds and one large circular pond used to conduct tests on fish using various mixtures of river and reactor effluent water. The current site conditions achieve the remedial action objectives specified in the Remaining Sites ROD. The results of verification and applicable confirmatory sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River

  7. Applying systems biology methods to the study of human physiology in extreme environments

    OpenAIRE

    Edwards, Lindsay; Thiele, Ines

    2013-01-01

    Systems biology is defined in this review as ‘an iterative process of computational model building and experimental model revision with the aim of understanding or simulating complex biological systems’. We propose that, in practice, systems biology rests on three pillars: computation, the omics disciplines and repeated experimental perturbation of the system of interest. The number of ethical and physiologically relevant perturbations that can be used in experiments on healthy humans is extr...

  8. Aspects of Aquatic Pollution in Nigeria

    Directory of Open Access Journals (Sweden)

    A.T. Ekubo

    2011-11-01

    Full Text Available Water pollution is a major problem in the global context. Yet aquatic resources consists of extremely wide range of floral and fauna resources which offer a broad array of goods with potential utilitarian application in agriculture, innovative industry and the pharmaceutical industry which renders valuable benefits and services. The slow poisoning of the waters is witnessed in Nigeria and the destruction of vegetation and agricultural land by oil spills which occur during petroleum operations. But since the inception of the oil industry in Nigeria, more than twenty-five years ago, there has been no concerned and effective effort on the part of the government, let alone the oil operators, to control environmental problems associated with the industry'. The article reviews the meaning of water pollution, water pollution categories, point source pollution, non-point source pollution, ground water pollution, causes of water pollution, pathogens, chemicals and other contaminants, thermal pollution, transport and chemical reactions of pollution, measurement of pollution, sampling, physical testing, chemical testing, biological testing, control of water pollution, domestic sewage, industrial waste water, agricultural waste water, construction site storm water urban runoff (storm water, radiation pollution, the Federal Environmental Protection Agency, The National Policy on Environment, The national environmental reference laboratory, Water resources management, Strategies under the National Policy on Environment, Industrial water pollution control programme, Industrial effluent standards to provide some information on the Nigeria situation.

  9. Aquatic Pest Control. Sale Publication 4071.

    Science.gov (United States)

    Wamsley, Mary Ann, Ed.; Vermeire, Donna M., Ed.

    The information in this manual applies to control of aquatic pests in recreational waters, agricultural reservoirs, ornamental ponds, coastal bays, estuaries and channels, and drinking water reservoirs. Mechanical, cultural, biological, and chemical control methods are discussed. The majority of the material is devoted to weed control in static…

  10. Aquatic intervention in children with neuro-motor impairments

    OpenAIRE

    Getz, M.D.

    2006-01-01

    The present thesis addresses the influence of aquatic interventions on motor performance of children with neuro-motor deficiencies in a functional context. The theoretical framework is based on a functional approach in compliance to the International Classification of Function and Disability (ICF). Chapter 2 addresses the relationship between motor performance in the aquatic environment setting as measured by the Aquatic Independence Measure (AIM) to motor performance on land as measured by t...

  11. Implications of aquatic animal health for human health.

    OpenAIRE

    Dawe, C J

    1990-01-01

    Human health and aquatic animal health are organically related at three distinct interfaces. Aquatic animals serve as important contributors to the nutritional protein, lipid, and vitamin requirements of humans; as carriers and transmitters of many infectious and parasitic diseases to which humans are susceptible; and as indicators of toxic and carcinogenic substances that they can convey, in some part, from aquatic environments to man and other terrestrial animals. Transcending these relatio...

  12. Spreading of Oil Spill on Placid Aquatic Medium

    OpenAIRE

    Derrick O. NJOBUENWU; Millionaire F. N. ABOWEI

    2008-01-01

    Continuous research in the development of suitable predictive model is vital as the input of oil spills into the aquatic environment particularly in the Niger Delta area of Nigeria is alarming due to frequent oil spills. This eventually affects aquatic organisms and shoreline activities. This work developed an semi-empirical expression that can predict the horizontal spreading of Niger Delta Oil Spills (NDOS) on a placid water body using simple physical coefficients of the oil and the aquatic...

  13. The Open Microscopy Environment (OME) Data Model and XML file: open tools for informatics and quantitative analysis in biological imaging

    OpenAIRE

    Goldberg, Ilya G.; Allan, Chris; Burel, Jean-Marie; Creager, Doug; Falconi, Andrea; Hochheiser, Harry; Johnston, Josiah; Mellen, Jeff; Sorger, Peter K.; Swedlow, Jason R

    2005-01-01

    The Open Microscopy Environment (OME) defines a data model and a software implementation to serve as an informatics framework for imaging in biological microscopy experiments, including representation of acquisition parameters, annotations and image analysis results. OME is designed to support high-content cell-based screening as well as traditional image analysis applications. The OME Data Model, expressed in Extensible Markup Language (XML) and realized in a traditional database, is both ex...

  14. Biologically inspired design framework for Robot in Dynamic Environments using Framsticks

    OpenAIRE

    S., Raja Mohamed; Raviraj, P.

    2012-01-01

    Robot design complexity is increasing day by day especially in automated industries. In this paper we propose biologically inspired design framework for robots in dynamic world on the basis of Co-Evolution, Virtual Ecology, Life time learning which are derived from biological creatures. We have created a virtual khepera robot in Framsticks and tested its operational credibility in terms hardware and software components by applying the above suggested techniques. Monitoring complex and non com...

  15. The pervasive role of biological cohesion in bedform development

    OpenAIRE

    Malarkey, Jonathan; Jaco H Baas; Hope, Julie A.; Rebecca J Aspden; Parsons, Daniel R.; Peakall, Jeff; Paterson, David M; Schindler, Robert J.; Ye, Leiping; Lichtman, Ian D.; Bass, Sarah J.; Davies, Alan G.; Manning, Andrew J.; Thorne, Peter D.

    2015-01-01

    Sediment fluxes in aquatic environments are crucially dependent on bedform dynamics. However, sediment-flux predictions rely almost completely on clean-sand studies, despite most environments being composed of mixtures of non-cohesive sands, physically cohesive muds and biologically cohesive extracellular polymeric substances (EPS) generated by microorganisms. EPS associated with surficial biofilms are known to stabilize sediment and increase erosion thresholds. Here we present experimental d...

  16. The radiological situation at the atolls of Mururoa and Fangataufa. Technical report. V. 2. Radionuclide concentrations measured in the aquatic environment of the atolls

    International Nuclear Information System (INIS)

    A marine monitoring programme was carried out within the framework of the IAEA's project entitled ''Study of the Radiological Situation at Mururoa and Fangataufa Atolls'' with the aim of assessing present radionuclide concentrations in the marine environment of Mururoa and Fangataufa Atolls. The terms of reference of the marine working group (WG2) included a review of the data provided by the French authorities on radionuclide distributions in the littoral and sub-littoral environments at the atolls. Further, using accredited international laboratories, it was decided to carry out sufficient and new independent monitoring work at and around the atolls in order to validate existing French data and, the same time, to provide a representative and high quality data set on current radionuclide concentrations in the marine environment, with particular reference to the requirement of Task Group A for radiological assessment purposes. This work included measurements of the current radionuclide concentrations in the marine environment, and estimation of concentration factors and Kd values appropriate for the region. The variations in activity concentrations in the lagoons over the past few years are discussed, and the likely sources of activity implied by these data are identified where possible

  17. Species management in aquatic habitats WRc RD Interim 1997

    OpenAIRE

    1997-01-01

    This is the Species management in aquatic Habitats WRc Interim 1997 document produced by the Environment Agency in 1997. This document reports progress on R&D Project 640, which aims to provide information on species of conservation value of particular relevance to the Environment Agency, in relation to its activities affecting aquatic environments. A range of stand-alone outputs is being produced, comprising Species Action Plans, practical management guidelines for Agency staff and third par...

  18. The drivers of corporate environment inputs: Based on neo-institution theory evidence from Chinese listed biological and other companies.

    Science.gov (United States)

    Guo, Rui; Tao, Lan; Yan, Liang; Chen, Lianfang; Wang, Haijun

    2014-09-01

    From corporate internal governance structure and external institutional environment, this study uses a legitimacy perspective of intuitional theory to analyze the main influence factors on corporate environmental protection inputs and propose some hypotheses. With the establishment of empirical models, it analyzes the data of 2004-2009 listed biological and other companies in China to test the hypotheses. The findings are concluded that in internal institutional environment, the nature of the controlling shareholder, the proportion of the first shareholder in the ownership structure, the combination of chairman and general manager in board efficiency and the intensity of environmental laws and regulations of the industry in external institutional environment have an significant impact on the behaviors of corporate environmental protection inputs. PMID:25262526

  19. Aquatic Life Benchmarks

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Aquatic Life Benchmarks is an EPA-developed set of criteria for freshwater species. These benchmarks are based on toxicity values reviewed by EPA and used in...

  20. Aquatic Research Laboratory (ARL)

    Data.gov (United States)

    Federal Laboratory Consortium — Columbia River and groundwater well water sources are delivered to the Aquatic Research Laboratory (ARL), where these resources are used to conduct research on fish...