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Isotopes in Environmental and Health Studies

E A N V Edirisinghe, H M T G A Pitawala, H A Dharmagunawardhane, R L Wijayawardane
Seasonal and spatial variation in δ(18)O and δ(2)H in rainwater was determined in three selected transects across Sri Lanka, the tropical island in the Indian Ocean. Local meteoric water lines (LMWLs) for three distinguished climatic zones; wet, dry and intermediate were constructed. LMWLs show slight variations in their gradients and respective d-excess values, depending on the air moisture origin, circulation and environmental conditions of each climatic zone. The elevation effect and amount effect could be identified but the continental effect is not significantly seen in the isotope composition of rain in the concerned areas...
April 6, 2017: Isotopes in Environmental and Health Studies
Sarah L Newberry, Ulrich E Prechsl, Matthew Pace, Ansgar Kahmen
Cryogenic vacuum extraction is the well-established method of extracting water from soil for isotopic analyses of waters moving through the soil-plant-atmosphere continuum. We investigate if soils can alter the isotopic composition of water through isotope memory effects, and determined which mechanisms are responsible for it. Soils with differing physicochemical properties were re-wetted with reference water and subsequently extracted by cryogenic water distillation. Results suggest some reference waters bind tightly to the soil and not all of this tightly bound water is removed during cryogenic vacuum extraction...
March 23, 2017: Isotopes in Environmental and Health Studies
Henrik Kusche, Nicola Hillgruber, Yvonne Rößner, Ulfert Focken
Brittle stars (Ophiura spp.) and other benthic macrofauna were collected in a prospective mariculture area in the North Sea to determine if these taxa could be used as indicator species to track nutrients released from future offshore aquaculture sites. We analysed natural carbon and nitrogen stable isotopic signatures in tissues from macrofauna and compared these to six feed ingredients and four experimental diets made thereof, as well as to a commercial feed with and without lipid and carbonate removal. Our data suggest practicability of using isotopic signatures of Ophiura spp...
March 20, 2017: Isotopes in Environmental and Health Studies
Frank Hülsemann, Karsten Koehler, Jürgen Wittsiepe, Michael Wilhelm, Annett Hilbig, Mathilde Kersting, Hans Braun, Ulrich Flenker, Wilhelm Schänzer
Natural stable isotope ratios (δ(15)N) of humans can be used for nutritional analyses and dietary reconstruction of modern and historic individuals and populations. Information about an individual's metabolic state can be obtained by comparison of tissue and dietary δ(15)N. Different methods have been used to estimate dietary δ(15)N in the past; however, the validity of such predictions has not been compared to experimental values. For a total of 56 meals and 21 samples of 24-h diets, predicted and experimental δ(15)N values were compared...
March 15, 2017: Isotopes in Environmental and Health Studies
W M Abdellah, H M Diab, S U El-Kameesy, E Salama, S El-Framawy
Twenty soil and 25 sediment samples were collected from the banks and bottom of the River Nile in the surroundings of biggest cities located close to it. Natural radioactivity concentrations of (226)Ra, (232)Th and (40)K have been evaluated for all samples by means of γ spectrometric analysis. The radioactivity levels of soil and sediment samples fall within the internationally recommended values. Nevertheless, high natural background radiation zones are detected in the Kafr El-Zayat region due to the presence of a fertilizer factory, and in the Rosetta region due to the presence of black sand deposits...
March 13, 2017: Isotopes in Environmental and Health Studies
Christian Fabiansen, Charles W Yaméogo, Sarita Devi, Henrik Friis, Anura Kurpad, Jonathan C Wells
Childhood malnutrition is highly prevalent and associated with high mortality risk. In observational and interventional studies among malnourished children, body composition is increasingly recognised as a key outcome. The deuterium dilution technique has generated high-quality data on body composition in studies of infants and young children in several settings, but its feasibility and accuracy in children suffering from moderate acute malnutrition requires further study. Prior to a large nutritional intervention trial among children with moderate acute malnutrition, we conducted pilot work to develop and adapt the deuterium dilution technique...
March 3, 2017: Isotopes in Environmental and Health Studies
Johannes A C Barth, Michael Mader, Franziska Nenning, Robert van Geldern, Kurt Friese
The aim of this study was to identify sources of carbon turnover using stable isotope mass balances. For this purpose, two pre-reservoirs in the Harz Mountains (Germany) were investigated for their dissolved and particulate carbon contents (dissolved inorganic carbon (DIC), dissolved organic carbon, particulate organic carbon) together with their stable carbon isotope ratios. DIC concentration depth profiles from March 2012 had an average of 0.33 mmol L(-1). Increases in DIC concentrations later on in the year often corresponded with decreases in its carbon isotope composition (δ(13)CDIC) with the most negative value of -18...
February 13, 2017: Isotopes in Environmental and Health Studies
Wendell Costa Bila, Reysla Maria da Silveira Mariano, Valmin Ramos Silva, Maria Emília Soares Martins Dos Santos, Joel Alves Lamounier, Eduardo Ferriolli, Alexsandro Sobreira Galdino
The main aim goal of this review was to gather information about recent publications related to deuterium oxide (D2O), and its use as a scientific tool related to human health. Searches were made in electronic databases Pubmed, Scielo, Lilacs, Medline and Cochrane. Moreover, the following patent databases were consulted: EPO (Espacenet patent search), USPTO (United States Patent and Trademark Office) and Google Patents, which cover researches worldwide related to innovations using D2O.
February 6, 2017: Isotopes in Environmental and Health Studies
Klaus-Peter Götz, Osman Erekul, Klaus Dieter Wutzke, Yakup Onur Koca, Tuğçe Aksu
This study examined the effects of a reduced wheat sowing rate (250 vs. 500 grains m(-2)) on grain yield, uptake of (15)N into grains, and the incorporation into gluten and non-gluten proteins of wheat under field conditions in the Aegean region. A single (15)N application was applied at stem elongation, at flowering, or at both developmental stages. Each (15)N treatment included either additional water supply, or no additional water supply at flowering. Sowing rate (either 250 or 500 grains m(-2)) had no impact on grain yield...
June 2017: Isotopes in Environmental and Health Studies
Mirjam S Studer, Roland Künzli, Reto Maier, Michael W I Schmidt, Rolf T W Siegwolf, Ivan Woodhatch, Samuel Abiven
Plant-soil interactions are recognized to play a crucial role in the ecosystem response to climate change. We developed a facility to disentangle the complex interactions behind the plant-soil C feedback mechanisms. The MICE ('Multi-Isotope labelling in a Controlled Environment') facility consists of two climate chambers with independent control of the atmospheric conditions (light, CO2, temperature, humidity) and the soil environment (temperature, moisture). Each chamber holds 15 plant-soil systems with hermetical separation of the shared above ground (shoots) from the individual belowground compartments (roots, rhizosphere, soil)...
June 2017: Isotopes in Environmental and Health Studies
Raminta Skipitytė, Agnė Mašalaitė, Andrius Garbaras, Rūta Mickienė, Ona Ragažinskienė, Violeta Baliukonienė, Bronius Bakutis, Jūratė Šiugždaitė, Saulius Petkevičius, Audrius Sigitas Maruška, Vidmantas Remeikis
Stable isotope analysis was applied to describe the poultry house environment. The poultry house indoor environment was selected for this study due to the relevant health problems in animals and their caretakers. Air quality parameters including temperature, relative humidity, airflow rate, NH3, CO2 and total suspended particles, as well as mean levels of total airborne bacteria and fungi count, were measured. Carbon isotope ratios ((13)C/(12)C) were obtained in size-segregated aerosol particles. The carbon ((13)C/(12)C) and nitrogen ((15)N/(14)N) isotope ratios were measured in feed, litter, scrapings from the ventilation system, feathers and eggs...
June 2017: Isotopes in Environmental and Health Studies
Martina Burnik Šturm, Oyunsaikhan Ganbaatar, Christian C Voigt, Petra Kaczensky
For certain remote areas like Mongolia, field-based precipitation, surface and ground water isotopic data are scarce. So far no such data exist for the Mongolian Gobi desert, which hinders the understanding of isotopic fractionation processes in this extreme, arid region. We collected 26 event-based precipitation samples, 39 Bij river samples, and 75 samples from other water bodies in the Dzungarian Gobi in SW Mongolia over a period of 16 months for hydrogen and oxygen stable isotope analysis. δ(2)H and δ(18)O values in precipitation show high seasonal variation and cover an extreme range: 175 ‰ for δ(2)H and 24 ‰ for δ(18)O values...
May 2017: Isotopes in Environmental and Health Studies
Kristina L Hitzfeld, Matthias Gehre, Hans-Hermann Richnow
In this study conversion conditions for oxygen gas chromatography high temperature conversion (HTC) isotope ratio mass spectrometry (IRMS) are characterised using qualitative mass spectrometry (IonTrap). It is shown that physical and chemical properties of a given reactor design impact HTC and thus the ability to accurately measure oxygen isotope ratios. Commercially available and custom-built tube-in-tube reactors were used to elucidate (i) by-product formation (carbon dioxide, water, small organic molecules), (ii) 2nd sources of oxygen (leakage, metal oxides, ceramic material), and (iii) required reactor conditions (conditioning, reduction, stability)...
May 2017: Isotopes in Environmental and Health Studies
Latife Sahin, Nurgül Hafızoğlu, Hakan Çetinkaya, Kaan Manisa, Engin Bozkurt, Ahmet Biçer
The analysis of natural radioactivity from (238)U, (232)Th and (40)K in 357 soil samples collected from the province of Kütahya was carried out using a NaI(Tl) gamma-ray spectroscopy system at the Nuclear Physics Research Laboratory, Dumlupınar University, Kütahya, Turkey. The specific activities of (238)U, (232)Th and (40)K in the soil samples were evaluated. From the activity concentrations of (238)U, (232)Th and (40)K, the total absorbed outdoor gamma-ray dose rates and the corresponding annual effective dose rates were determined...
May 2017: Isotopes in Environmental and Health Studies
Dagmara I Strumińska-Parulska
The idea behind this study was to investigate the most popular magnesium dietary supplements as a potential additional source of (210)Pb in the human diet. The paper presents the results of (210)Pb activities determined in different magnesium supplements, as well as an estimation of the annual effective radiation doses from (210)Pb decay. The results showed that the highest value of (210)Pb activity was found in a magnesium supplement of natural origin (dolomite) with a value of 2.97 ± 0.18 mBq g(-1). The highest annual radiation dose from (210)Pb obtained from the magnesium daily recommended value (0...
May 2017: Isotopes in Environmental and Health Studies
Simin Qu, Yifan Wang, Minmin Zhou, Han Liu, Peng Shi, Zhongbo Yu, Long Xiang
The differences between δ(18)O and δ(2)H in throughfall and open rainfall were studied for a selected typhoon event in a watershed within the Taihu Lake drainage basin, eastern China. In this event, the isotopic composition of precipitation exhibited a strong temporal variation. Comparison results show that an isotopic composition difference existed not only between gross rainfall and average incremental rainfall, but also between different calculation methods used to derive average. The differences between incremental precipitation and throughfall isotopic composition were observed in this study...
May 2017: Isotopes in Environmental and Health Studies
Galip Yuce, Francesco Italiano, Didem Yasin, Lutfi Taskiran, Ahmet Hilmi Gulbay
The thermal fluids vented over Eskisehir province have been investigated for their origin and to estimate the geothermal potential of the area. Thermal waters as well as bubbling and dissolved gases were collected and analysed for their chemical and isotopic features. Their isotopic composition varies in the range from -11.5 to -7.7 ‰ for δ(18)O, -84 and -57 ‰ for δ(2)H, and 0-7.2 TU for tritium. The gases (bubbling and dissolved) are mostly N2-dominated with a significant amount of CO2. The helium isotopic ratios are in the range of 0...
May 2017: Isotopes in Environmental and Health Studies
Hatem Elmarami, Hanno Meyer, Gudrun Massmann
Stable isotopes of hydrogen and oxygen are often used for water balance calculations of lakes. We present an approach combining the lake water balance with an isotope mass balance to constrain the sources and sinks of the water of a small dimictic lake subjected to eutrophication. Meteorological and hydraulic data in combination with measured isotope signatures of the different water compartments enabled to assess the degree of surface water/groundwater interaction and the amount of overland flow into the lake...
May 2017: Isotopes in Environmental and Health Studies
Vasily A Vavilin, Sergey V Rytov
To identify predominant metabolic pathway for cellulose methanization new equations that take into account dynamics of 13C are added to the basic model of cellulose methanization. The correct stoichiometry of hydrolysis, acidogenesis, acetogenesis and methanogenesis steps including biomass is considered. Using experimental data by Laukenmann et al. [Identification of methanogenic pathway in anaerobic digesters using stable carbon isotopes. Eng. Life Sci. 2010;10:1-6], who reported about the importance of ace`tate oxidation during mesophilic cellulose methanization, the model confirmed that, at high biomass concentration of acetate oxidizers, the carbon isotope fractionation factor amounts to about 1...
May 2017: Isotopes in Environmental and Health Studies
Lei Fujiyoshi, Atsuko Sugimoto, Akemi Tsukuura, Asami Kitayama, M Larry Lopez Caceres, Byambasuren Mijidsuren, Ariunaa Saraadanbazar, Maki Tsujimura
The spatial patterns of plant and soil δ(15)N and associated processes in the N cycle were investigated at a forest-grassland boundary in northern Mongolia. Needles of Larix sibirica Ledeb. and soils collected from two study areas were analysed to calculate the differences in δ(15)N between needle and soil (Δδ(15)N). Δδ(15)N showed a clear variation, ranging from -8 ‰ in the forest to -2 ‰ in the grassland boundary, and corresponded to the accumulation of organic layer. In the forest, the separation of available N produced in the soil with (15)N-depleted N uptake by larch and (15)N-enriched N immobilization by microorganisms was proposed to cause large Δδ(15)N, whereas in the grassland boundary, small Δδ(15)N was explained by the transport of the most available N into larch...
March 2017: Isotopes in Environmental and Health Studies
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