Dissertations / Theses: 'Trace elements in water'

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Wong, Wang-wah. "Trace organics pollution in the aquatic environment /." [Hong Kong] : University of Hong Kong, 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13498356.

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Di, Bonito Marcello. "Trace elements in soil pore water : a comparison of sampling methods." Thesis, University of Nottingham, 2005. http://eprints.nottingham.ac.uk/10123/.

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This thesis examined a range of methods for sampling soil pore water to investigate the chemistry of trace elements. In particular, the study assessed whether Rhizon samplers, centrifugation, high pressure squeezing and soil suspensions in simulated pore water can be viable approaches for obtaining representative samples of equilibrated soil pore water. Results for metal solubility and speciation were interpreted in terms of both soil morphological effects on trace metal dynamics and artefacts introduced at various stages during sample preparation and handling. The main soil used in the study was an organic-rich sandy silt from a site which has served as a sewage re-processing facility for almost a century. This soil was chosen because of its importance as a long-term repository for metal-enriched sludge applied to arable land, providing a suitable medium on which to study trace metal behaviour. Pore waters were extracted and analysed for major and trace cations and anions, pH, Dissolved Inorganic Carbon (DIC) and Dissolved Organic Carbon (DOC) at two different temperatures (5 degrees Celsius and 15 degrees Celsius), in order to evaluate the extent of bacterial activity, organic decomposition and their consequences on solute composition, during pore water extractions. Speciation was estimated from analysis of pore water chemistry using two software packages (PHREEQCi and WHAM-VI). Pore waters showed different ranges of concentration between the various methods. Different mechanisms and/or chemical reactions were involved during the different extractions; a range of processes was identified, mainly dominated by metal complexation by humus acids and redox reactions. Results revealed that the soil studied was able to partially buffer the free ion activities of the metal ions in pore water with increasing dilutions, but demonstrated virtually no ability to buffer DOC. Identification of the source (i.e. location of pore space) of water extracted was also investigated using water with different isotopic composition (18O/16O). Evidence showed that centrifugation was not able to differentiate between more and less mobile water at FC conditions, rather enhancing the mixing between the two pools of water (native and labelled) by and apparent process of 'infusion'. By contrast, Rhizon samplers appeared to sample water preferentially from the more accessible pool (extra-aggregate), which proved to have a composition showing incomplete mixing with the native water. The results also suggested that mixing of the two pools was rather fast and that was almost completely attained prior to pore water extraction. The study established that the most important factors affecting pore water chemistry during extraction are the conditions to which the samples are exposed during the extraction process. For these reasons Rhizon samplers should be used as a disposable device, and are only applicable for use in high soil moisture soil contents. In contrast, they present no 'side-effects' (providing enough equilibration time) if M2+ (free ion activity) were needed as opposed to Msol (total metal concentration in pore water), as often required in environmental studies. Centrifugation is optimal for bulk solution studies, or when homogenisation represents a key experimental point; targeted studies are also possible. Soil squeezing is subject to severe limitations in the case of prolonged extractions of biologically active soils, due to the effects of anaerobism. Squeezing should only be used for 'fast' extractions of soils. Finally, batch extractions are well suited to studies on M2+ equilibria, but more studies are needed to clarify the effect of soil: solution ratio on metal and DOC solubility.

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Morabito, Elisa <1978&gt. "The role of speciation in trace elements distribution in sea water." Doctoral thesis, Università Ca' Foscari Venezia, 2009. http://hdl.handle.net/10579/171.

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Pan, Jinfen. "Bioavailability of trace metals to marine bivalves mediated by dissolved and colloidal organic carbon /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?BIOL%202004%20PAN.

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Denney, Susan, and susan denney@deakin edu au. "Trace metal speciation in the Pieman River catchment, Western Tasmania." Deakin University. School of Ecology and Environment, 2000. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20071107.111755.

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The Pieman River catchment has seen continuous mining of economic deposits of gold, silver, lead, copper, zinc and tin since the 1870s. Tributaries of this river which receive mining effluent, either directly or from acid mine drainage (AMID), have total metal concentrations considerably above background levels and are of regulatory concern. The lower Pieman River is however classified as a State Reserve in which recreational fishing and tourism are the major activities. It is therefore important that water entering the lower Pieman River from upstream hydroelectric impoundments is of high quality. Metals in natural waters exist in a variety of dissolved, colloidal and particulate forms. The bioavailability and hence toxicity of heavy metal pollutants is very dependant on their physico form. Knowledge of the speciation of a metal in natural aquatic environments is therefore necessary for understanding its geochemical behaviour and biological availability. Complexation of metal ions by natural ligands in aquatic systems is believed to play a significant role in controlling their chemical speciation. This study has investigated temporal and spatial variation in complexation of metal ions in the Pieman River. The influence of pH, temperature, organic matter, salinity, ionic strength and time has been investigated in a series of field studies and in laboratory-based experiments which simulated natural and anthropogenic disturbances. Labile metals were measured using two techniques in various freshwater and estuarine environments. Diffusive gradients in thin-films (DGT) allowed in situ measurement of solution speciation whilst differential pulse anodic stripping voltammetry (DPASV) was used to measure labile metal species in water samples collected from the catchment. Organic complexation was found to be a significant regulating mechanism for copper speciation and the copper-binding ligand concentration usually exceeded the total copper concentration in the river water. Complexation was highly dependent on pH and at the river-seawater interface was also regulated by salinity, probably as a result of competitive complexation by major ions in seawater (eg. Ca 2+ ions). Zinc complexation was also evident, however total zinc concentrations in the water column often far exceeded the potential binding capacity of available ligands. In addition to organic complexation, Zn speciation may also be associated with adsorption by flocculated or resuspended colloidal Mn and/or Fe oxyhydroxides. Metal ion complexation and hence speciation was found to be highly variable within the Pieman River catchment. This presents major difficulties for environmental managers, as it is therefore not possible to make catchment-wide assumptions about the bioavailability of these metals. These results emphasise the importance of site-specific sampling protocols and speciation testing, ideally incorporating continuous, in situ monitoring.

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Jin, Li. "Determination of trace metals and copper complexation in freshwater systems of the Bonavista Peninsula, Newfoundland by stripping voltammetry." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq25853.pdf.

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7

Jaafar, Maisarah. "Trace elements in natural water : the impact on quality, food preparation and production." Thesis, University of Surrey, 2018. http://epubs.surrey.ac.uk/846339/.

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The levels of arsenic (total and species) and other trace elements in natural waters of Argentina were analysed using inductively coupled plasma mass spectrometer (ICP-MS). In addition, a method was developed for the determination of Mo in waters using graphite furnace atomic absorption spectrometry (GFAAS) with an added palladium chemical modifier. The analysis of Mo in certified reference materials and water samples using both methods confirmed no statistical difference using a paired t-test (tcal = 0.276; tcrit = 2.160, df: 14 at p<0.05). Arsenic total levels (AsT) in groundwaters followed the order; central-north La Pampa (48.82-1442.60 μg/l) > south-east La Pampa (17.66-319.39 μg/l) > southern Buenos Aires (39.6-189.4 μg/l) > Río Negro/Río Colorado (1.03-38.66 μg/l). The distribution of As species (using a field-based solid phase extraction method) were significantly different between the sampling regions. In most of the study areas the groundwater exceeded 10 μg/l AsT (World Health Organisation guideline for drinking water) and can be deemed to be not fit for human consumption since the calculated hazard quotient (HQ) >1. Apart from As, Mo and V also showed higher levels in groundwaters relating to the historical deposition of volcanic ash within the Chaco-Pampean plain of Argentina. The groundwaters from La Pampa ranged from 10 to 84 μg/l Mo. Surprisingly, one farm well south of Eduardo Castex (central-northern La Pampa) used for cattle drinking water had 1381.66 μg/l Mo. Significant positive correlations were found for As, Mo and V between groundwaters used on agricultural lands and the associated soils and pastures. The arsenic concentrations in groundwaters were found to be statistically correlated (r > 0.5) with the corresponding soils (total and exchangeable fraction) and plants (leaves and roots) at p < 0.01. Based on a sequential extraction method for soils, the uptake of arsenic from the soil exchangeable fraction by plants was found to be statistically correlated (rleaves = 0.5 and rroots = 0.7 at p < 0.01). Furthermore, the use of local groundwaters for food preparation (washing and cooking) alters the elemental composition of local foodstuffs (carrots, potatoes, onions and rice). The transfer of As, Mo, V, Mn, Fe, Cu, Zn from the water to foodstuffs was found to be dependent on the levels in the water, washing steps and the cooking process (time and method). A higher uptake of As, Mo and V by foodstuffs was observed when cooking with highly ̳contaminated‘ groundwaters, especially for rice. This may significantly increase the daily dietary intake of these elements as a function of food consumption. However, drinking water (2 l/day) is still considered the main contributor to the total daily intake of As, Mo and V for the local residents who rely upon groundwater as their source for drinking and cooking due to the lower Argentine food consumption rate (38 - 196 g/day). Similar trends were observed in West Bengal, India involving rice production and preparation (washing and cooking). Elevated levels were observed for As, Mn and Fe for all sample types (plants, soils, raw and prepared rice) in relation to the use of local groundwaters. Consumption of cooked rice (500 - 750 g/day) was observed to be the major contributor to the total daily dietary intake of As, Mn and Fe (depending on the rice variety) in the Indian study area when the local groundwater (94 μg/l AsT) was used in the preparation of rice, especially for local grown rice varieties.

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Benneyworth, Laura Mahoney. "Distribution of Trace Elements in Cumberland River Basin Reservoir Sediments." TopSCHOLAR®, 2011. http://digitalcommons.wku.edu/theses/1113.

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The U.S. Army Corps of Engineers, Nashville District, maintains ten reservoirs in the Cumberland River Basin in Kentucky and Tennessee, and has been monitoring sediment chemistry in the reservoirs since 1994. The purpose of this study is to evaluate the sediment data collected from the reservoirs from 1994 to 2010 to determine if there are any spatial patterns of the trace elements: arsenic, beryllium, cadmium, chromium, copper, lead, mercury, nickel, and zinc. The results indicated that trace element levels were consistent with national baseline concentrations measured by the U.S. Geological Survey. Center Hill reservoir had the greatest number of trace element concentrations (all except cadmium) that were significantly higher when compared to all other reservoirs. The degree of urbanization in the reservoir basins was based on population density from the 2000 Census and the percentage of developed land using the 2006 national land cover dataset. Aquatic toxicity values were used as a measure of sediment quality. The reservoirs with the worst aquatic toxicity rankings were not the most urban, instead they were the reservoirs with the longest retention times. Therefore, it may be concluded that retention time has a larger effect on Cumberland River Basin sediment concentrations than the type of land use or the degree of urbanization. The results also indicate that it may be prudent to include an evaluation of quality based on aquatic toxicity when monitoring sediment quality, and that when reservoirs are the subject of sediment quality assessments, the consideration of the physical properties of the reservoir, especially the retention time, is essential for a comprehensive evaluation. This may also imply that sediment quality in reservoirs may effectively be regulated by water resource management techniques at the reservoirs that affect retention time.

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Botes, Paul Johannes. "Investigation of mobility of trace elements in river sediments using ICP-OES." Pretoria : [s.n.], 2003. http://upetd.up.ac.za/thesis/available/etd-01182005-091457.

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Wilson, Jonathan. "Sorption of metals from aqueous solution by bone charcoal." Connect to e-thesis, 2002. http://theses.gla.ac.uk/756/.

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Thesis (Ph.D.) - University of Glasgow, 2002.
Ph.D. thesis submitted to Environmental, Agricultural and Analytical Chemistry, Chemistry Department, University of Glasgow, 2002. Includes bibliographical references. Print version also available.

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11

Hayes, Warwick Jay. "Chemical relationships in waters and sediments of some urban streams, with particular reference to heavy metals and phosphorus." University of Technology, Sydney. Department of Environmental Biology and Horticulture, 1996. http://hdl.handle.net/2100/361.

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This thesis describes two studies of the chemistry of freshwater streams in the Sydney basin. The first was a survey of 86 waterways, sampled under low conditions. Samples were generally low in salinity, soft, of poor buffering capacity and dominated by sodium and chloride. C0-dominance by calcium, magnesium and (bi)carbonate occured in a number of particular cases. Multivariate analyses indicated three groups, separated primarily by levels of dissolved nutrients, trace metals, turbidity and colour. Groupings were associated strongly with the type of catchment. Streams in areas relatively unaffected by human influence had notable uniformity in chemistry, while those from developed catchments were varied. Heavy metal contamination was relatavely low, although a few of the samples displayed inordinately large levels of one or more metals. In such cases the more extreme measurements of phosphorus and nitrogen were also seen. The findings were consistant with occasional or localised elevation of contaminant levels. The second study invloved monitoring of three Hawkesbury Sandstone streams. Sampling of surface waters, interstial waters and sediments was performing at irregular intervals over a two year period at three stations within each site. The streams predominantly existed under low conditions and showed similar major ion chemistries to the majority of the survey samples. Levels of calcium and total carbonate, plus heavy metals and nutrients were generally higher in the urbanised creeks, comapred to the reference strema. During a heavy storm, high levels of nutrients, suspended solids and colour were detected in all surface waters at peak-flow, as well as alkaline pH, oxidising redox, and reduced conductivity, alkalinity and hardness. The sandy sediments were characterised by very low levels of organic matter and cation exchange capacity. Sequential extractions identified that the sums of secondary phase lead, zinc and copper were over nine, four and two times that of the corresponding residual, respectively. Greatest proportions of zinc and lead were associated with coatings of iron and maganese oxides, or coarse waste particles. Copper was preferentially associated with organic matter. Concentration gradients between interstitial and surface waters were rare and release of sedimentary constituents should occur from the upper-most particulates. Poor water and sediment qualities were often observed in the urban sites. Poor water quality was also seen on occassion in the reference stream. However, since poor sediment quality was not detected at those times and interstitial waters for all sites displayed high within-site variability, surface waters were considered the most reliable short-term indicator of condition for Hawkesbury Sandstone streams. Multidimensional scaling showed that all streams had distinct water and sediment chemistries. High levels of temporal and spatial variability were apparant within the urbanised sites - particularly in interstitial waters - mostly due to concentrations of heavy metals, phosphorus and suspended solids. Seasonal differences were detected, but only in terms of the level of variability between summer and winter samples.

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12

Chapin, Thomas P. "Trace metal cycling in the central equatorial Pacific : results from the U.S. JGOFS EqPac survey cruises /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/11029.

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13

SOUSA, KEILA C. P. M. de. "Estudo dos fluxos fluviais de isótopos naturais de rádio e bário dissolvido para as enseadas de Ubatuba, Litoral Norte do Estado de São Paulo." reponame:Repositório Institucional do IPEN, 2008. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11706.

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Made available in DSpace on 2014-10-09T12:54:57Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T14:07:04Z (GMT). No. of bitstreams: 1 12812.pdf: 8731040 bytes, checksum: c07544bfbe9cb89c2d4ba26ddd54a72e (MD5)
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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Al-rifai, Jawad Hilmi. "Performance of water recycling technologies." Access electronically, 2008. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20080918.125513/index.html.

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15

Le, Roux Shirley Theodora Rose. "The application of differential pulse stripping voltammetry in the determination of trace metals in wet precipitation." Thesis, Peninsula Technikon, 1999. http://hdl.handle.net/20.500.11838/742.

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Thesis (MTech (Physical Sciences))--Peninsula Technikon, Cape Town, 1999.
Wet deposition of toxic trace metals is the dominant mode of deposition in terrestrial ecosystems and contributes very significantly to their pollution burden. Wet deposited metals are dissolved in rainwater. They reach the vegatation in a form most favourable for uptake. Reliable analysis of toxic trace metals in rainwater is important in order to determine the impact they make on the environment. In this study, trace metals in rainwater and in dry deposition (as a control measure), have been analysed over a period of a year. These metals include cadmium, copper, cobalt, lead, nickel and zinc. The rainwater was filtered, acidified to pH2 and irradiated with UV-light. Dry deposition samples, were digested by heating in nitric acid before analysis. Differential-pulse anodic stripping voltammetry was used to determine cadmium, lead and zinc. Copper was determined by adsorptive cathodic stripping at pH7 after complexation with catechol. Cobalt and nickel were measured at pH9 by adsorptive cathodic stripping after formation of their dimethylglyoximes. Sampling was done on a daily basis from April 1996 to March 1997, on the campus of the Peninsula Technikon. The samples were collected over a 24-hour period. The total average concentration for the metals was 16.11 flg/dm3 for rainwater and 427flg/dm3 for dry deposition. Meteorological factors such as wind speed, humidity and temperature affect the distribution of pollutants and thus the trace metal levels. The levels of the metallic pollutants were thus evaluated against meteorological data. Differential-pulse stripping voltammetry is shown to be applicable for heavy metal analysis of rainwater.

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Al, Anqah Laila. "Trace element contaminants in the Kuwait water production system." Thesis, Brunel University, 1996. http://bura.brunel.ac.uk/handle/2438/5012.

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Fresh water in Kuwait is produced by non- conventional methods. About 95% of this water comes from desalinated seawater using multi-stage flash distillation technique and the remainder comes from underground brackish water. The blended water containes organic, inorganic and trace metal impurities within the recommended international standard limits. The purpose of this work is to identify the source of selected trace metals present in the drinking water in Kuwait. Chromium, copper, iron, lead, manganese, nickel, vanadium and zinc have been analysed using atomic absorption spectroscopy (AAS) and inductively coupled plasma mass spectroscopy (ICPMS). Efforts were made to improve the preconcentration of the selected metals and their separation from the high concentration of salts in seawater which affect the accuracy and cause major interference in the analysis. Solid-liquid extraction (chelex-100 resin) and liquid-liquid extraction (methyl iso-butyl ketone and freon) with and without back-extraction into nitric acid were investigated. Liquid-liquid extraction without back-extraction proved to give optimum recovery of the selected metals. Results confirmed that both AAS and ICP-MS are suitable for the analysis of trace metals in Kuwait's waters. Although AAS technique proved to be more accurate in analysing the selected metals than ICP-MS, the latter was adopted since its accuracy is acceptable (1.1-4.4%) and it is easier and faster than the former technique. The study revealed that the source of copper, iron, nickel and zinc is the construction materials of the distillation plants, while the source of lead and vanadium is the brackish water. Manganese and chromium concentrations are very low in all sources. No direct relationship between the metal concentration in the seawater and the distillate could be deduced.

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Gangloff, Sophie. "Evaluation of the mechanisms of trace elements transport (Pb, Rare Earth Elements,... ) and the elemental and isotopic fractionation (Ca and Sr) at the interface water-soil-plant." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAH002/document.

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Ce travail est axé sur l’étude d’un profil de sol et des solutions de sol prélevés sur une parcelle expérimentale couvertes d’épicéas. Tous ces échantillons proviennent du Bassin Versant du Strengbach (Observatoire HydroGéochimique de l’Environnement – OHGE), ont été échantillonnés à différentes profondeurs (5, 10, 30 et 60 cm) et durant la période comprise entre 2009 et 2013.Les caractérisations des extraits des sols par spectroscopie Infra-Rouge ont permis de mettre en évidence les modifications des groupements fonctionnels organiques avec la profondeur et que ces modifications ont une forte incidence sur le comportement des cations (majeurs et traces) dans le sol. Des expérimentations d’ultra-filtration ont permis d’identifier les flux colloïdaux et dissous du carbone organique ainsi que ceux des éléments majeurs et traces présents dans les solutions de sol. L’utilisation conjointe des traceurs isotopiques (87Sr/86Sr et δ44/40Ca) et chimiques (Terres Rares) ont mis en évidence des processus ayant lieu aux interfaces eau-sol-plante, comme le prélèvement racinaire ou l’altération des sols
This work is focused on the study of a profile of soil and soil solutions collected on an experimental plot covered with spruce. All these samples come from the watershed of the Strengbach (environment - OHGE Hydrogeochimique Observatory), were sampled at different depths (5, 10, 30 and 60 cm) and during the period between 2009 and 2013. Characterizations of soil extracts by infrared spectroscopy allowed to highlight changes in the organic functional groups with depth and that these changes have a significant impact on the behaviour of the cations (major and trace) in the soil. Ultrafiltration experiments helped to identify flows of colloidal and dissolved organic carbon as well as those of the major and trace-element present in soil solutions. The joint use of isotope tracers (87Sr / 86Sr and δ44 / 40 Ca) and chemical (Rare Earth Elements) have highlighted processes taking place at the water-soil-plant interface, as the uptake by root or soil alteration

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Cuthbert, Iain Dawson. "Predicting the riverine concentrations and catchment exports of metals in rural drainage basins of Ontario and Québec." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60672.

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Concentrations of Fe, Al, Mn and Zn were measured monthly from April to October at 24 rural riverine sites in Ontario and Quebec. Empirical models were developed predicting riverine metal concentrations from a small set of within-stream and catchment variables. Models explained a significant proportion of the variation in Fe (85%), Al (90%), Mn (57%) and Zn (37%). Simple models predicting annual catchment exports of metals from average riverine suspended particulate concentrations and runoff were also developed. These models explained most of the variation in annual exports of Fe (94%), Al (92%), Mn (62%) and Zn (75%) from the 24 catchments.
Models such as these can be used both to estimate catchment exports of metals to lakes, and to estimate riverine metal concentrations without requiring chemical analyses. The models also serve to distinguish background levels from those indicating metal contamination, and will, therefore, be useful in design of water quality guidelines.

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Wong, Wang-wah, and 黃宏華. "Trace organics pollution in the aquatic environment." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1993. http://hub.hku.hk/bib/B31252758.

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Moragues, Quiroga Cristina. "Water mixing processes in the critical zone : evidence from trace elements and Sr-Nd-Pb-U isotopes." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAH002.

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Les fonctions hydrologiques de captage, stockage et rejet d’eau ont des signatures géochimiques dans les cours d'eau reflétant énormément celles trouvées dans les compartiments de la zone critique. Ces signatures sont fortement contrôlées par des processus bio-géophysico-chimiques produits dans l'interface régolite-plante. Jusqu'à présent, les recherches sur régolithes et processus hydrologiques sont restées largement découplées - conduisant à une utilisation généralisée de traceurs non conservateurs d'origines multiples, bloquant ainsi notre capacité à identifier les sources et les voies d'écoulement d’eau. Nous étudions ici le mélange d'eau dans la subsurface à travers un portefeuille unique de traceurs (éléments traces et isotopes O-H-Sr-Nd-Pb-U) permettant d'étudier les processus d'évolution du régolithe et le transport des solutés dans la zone critique. Nous signalons l'intérêt de cette approche pour renforcer la caractérisation des sources et voies d'écoulement d’eau
Catchment hydrological functions of water collection, storage and release have geochemical signatures in stream water largely mirroring those found in critical zone compartments. These signatures are strongly controlled by the different bio-geo-physico-chemical processes that occur within the regolith-plant interface. Until now, investigations into the critical zone’s regolith and hydrological processes research have largely remained uncoupled –leading to a widespread use of non-conservative tracers with multiple origins and thereby stymieing our capability for identifying water pools and flow paths. Here we study the mixing of water in the subsurface through a unique portfolio of complementary groups of tracers (trace elements O-Hand Sr-Nd-Pb-U isotopes) which enables investigating regolith evolution processes and solutes transport within the critical zone. We report the interest of this approach to strengthen water flowpaths and end-members characterization

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Riostantieka, Mayandari Shoedarto. "Water and rock geochemical characterization to clarify fluid circulation process in transitional geothermal reservoir with a case study of the Wayang Windu field, West Java, Indonesia." Kyoto University, 2020. http://hdl.handle.net/2433/253261.

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Bradshaw, Gerard Francis. "The distribution, sea water solubility and solid state speciation of some trace elements from the North Sea atmosphere." Thesis, University of Liverpool, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333683.

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23

Duernberger, Kimberley. "Tracing nitrogen through the food chain in an urbanized tidal creek." View electronic thesis (PDF), 2009. http://dl.uncw.edu/etd/2009-1/r3/duernbergerk/kimberleyduernberger.pdf.

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Taylor, Anne Marie, and n/a. "Biomarkers of Cadmium, Lead and Selenium Toxicity in the Marine Bivalve Molluscs Tellina deltoidalis and Anadara trapezia: Linking Exposure, Dose and Response." University of Canberra. Environmental Science, 2009. http://erl.canberra.edu.au./public/adt-AUC20091214.104734.

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The relationships between metal exposure, dose and response were investigated in two sediment dwelling marine bivalves: a deposit feeder Tellina deltoidalis and a filter feeder Anadara trapezia. The bivalves were exposed in the laboratory to individual metal spiked sediments: Cadmium 10 and 50 Ag/g; lead 100 and 300 Ag/g; selenium 5 and 20 Ag/g dry mass, T. deltoidalis for 28 days A. trapezia for 56 days. A. trapezia was also exposed in the laboratory for 56 days to sediments from three sites along a metal contamination gradient of cadmium, lead, selenium, zinc and copper from Lake Macquarie, NSW. Metal total tissue dose was measured in whole tissue of T. deltoidalis over 28 days and in gill, hepatopancreas and haemolymph tissues in A. trapezia over 56 days. Subcellular metal distribution, biologically active metal (BAM) versus biologically detoxified metal (BDM) was measured in whole tissues of T. deltoidalis at day 28 and in gill and hepatopancreas tissues of A. trapezia at day 56. Biomarkers of response measured in spiked sediment exposed, at day 28 T. deltoidalis and day 56 A. trapezia were: total antioxidant capacity (TAOC); glutathione peroxidase enzyme activity (GPx); total glutathione concentration (GSH+2GSSG); reduced to oxidised glutathione ratio (GSH:GSSG); lipid peroxidation (TBARS); lysosomal membrane stability and micronuclei frequency. Response indices measured in A. trapezia exposed to Lake Macquarie sediments were: TAOC, TBARS, lysosomal membrane stability, micronucleus frequency and condition index. Native A. trapezia and sediments were also collected from Lake Macquarie and measured for sediment and tissue metal concentrations, TAOC, TBARS, lysosomal membrane stability and condition index to allow comparison between chronically exposed and previously unexposed organisms. T. deltoidalis and A. trapezia accumulated metal over time in all sediment metal exposures with most reaching equilibrium tissue metal concentrations by the end of the exposure period. T. deltoidalis generally reached equilibrium with the exposure concentration for cadmium and lead but had significantly higher selenium tissue concentrations than the sediment metal at the 5 Ag/g exposure. A. trapezia tissue lead was below the sediment concentration for all exposures including in the native organisms. A high proportion of accumulated lead and copper in A. trapezia was in the haemolymph, probably associated with haemoglobin which has a high affinity for these metals`. A. trapezia cadmium tissue concentrations were higher than the sediment metal in the 10 Ag/g spiked sediment exposure and between half and one eighth the sediment concentrations in other treatments, including in native organisms. A. trapezia including the native organisms exposed to selenium sediment concentrations at or below 5 Ag/g in the Lake Macquarie mixed metal sediments accumulated significantly higher than ambient selenium tissue concentrations while those exposed to 5 and 20 Ag/g selenium spiked sediments had lower than ambient selenium tissue concentrations. The majority of accumulated cadmium, selenium and zinc was associated with the gill/mantle tissues. A. trapezia hepatopancreas contributed significant selenium concentrations in the later part of the exposure period indicating and increased contribution from dietary derived selenium. Native A. trapezia had significantly lower tissue concentrations of selenium, copper and zinc, higher cadmium and approximately equal lead compared to organisms exposed to similar sediment metal concentrations in the laboratory. T. deltoidalis detoxified around 50 % of accumulated cadmium and 70 % of lead while A. trapezia detoxified around 70 % of accumulated cadmium and 60 % of lead. Much of T. deltoidalis BDM cadmium was converted to metal rich granules (MRG), while A. trapezia had most in the metallothionein like proteins (MTLP) fraction. The conversion of lead to MRG was 75 % of the total BDM in T. deltoidalis while A. trapezia had an even distribution between MRG and MTLP. The majority of recovered selenium in both species was associated with the nuclei+cellular debris fraction, probably as protein bound selenium associated with plasma and selenium bound directly to cell walls. Selenium exposed organisms had increased BDM selenium burdens which were associated with both MRG and MTLP fractions, indicating selenium detoxification. The majority of BAM cadmium, lead and selenium was associated with the mitochondrial fraction in both species with increases in cadmium burden in this organelle of T. deltoidalis up to 7200 fold; lead 154 fold; and selenium 7 fold and in A. trapezia up to 84 fold cadmium, 50 fold lead and selenium 7 fold in exposed organisms compared to controls. The subcellular distribution of all three metals in T. deltoidalis and A. trapezia indicates active metal detoxification processes which at these exposure concentrations were unable to prevent significant metal burdens from accumulating in sensitive organelles. A contamination gradient of zinc, lead, copper, cadmium and selenium was established in Lake Macquarie sediments which emanated from the same source. A. trapezia accumulated all metals in each sediment exposure. Accumulation and tissue distribution patterns of cadmium, lead and selenium were similar to those of the single metal spiked sediment exposures. Cadmium and lead BAM burdens increased at all exposures while selenium, zinc and copper did not. T. deltoidalis and A. trapezia in the spiked sediment metal exposures generally had reduced GPx activity. This resulted in an increase in total glutathione concentrations which the reduced GSH:GSSG ratios indicated was due to a build up of oxidised glutathione. T. deltoidalis and A. trapezia had reduced TAOC in all laboratory sediment metal exposures which corresponded with increased TBARS concentrations, lysosomal destabilisation and micronucleus frequency. A. trapezia exposed to Lake Macquarie metal contaminated sediments also had a reduction in physiological condition, indicated by the reduced condition index, after 56 days at the higher metal exposures. Clear exposure - dose - response relationships have been demonstrated for T. deltoidalis and A. trapezia exposed to single cadmium, lead and selenium spiked sediments and for A. trapezia exposed to Lake Macquarie mixed metal contaminated sediments. Detoxification of all metals was evident in both T. deltoidalis and A. trapezia but detoxification capacity was exceeded for cadmium, lead and selenium leading to significant accumulation of these metals in sensitive organelles. The significant relationships, in the laboratory exposed T. deltoidalis and A. trapezia, between TAOC reduction with increased TBARS, lysosomal destabilisation and micronuclei frequency and between increased TBARS with lysosomal destabilisation and micronuclei frequency indicates that increased tissue metal dose and BAM burdens caused significant impairment of the antioxidant reduction capacity which resulted in a cascade of effects from lipid peroxidation to cellular perturbation and genotoxic damage. The reduction in physiological condition in the organisms with the highest tissue metal doses suggests the response goes beyond subcellular perturbations to whole organism and potentially population effects. Chronically metal exposed native Lake Macquarie A. trapezia did not show a clear metal exposure - dose - response relationship. Accumulation of the essential elements zinc, copper and selenium appeared to be regulated while cadmium and lead were not. TAOC was significantly reduced and TBARS significantly increased compared to reference organisms but lysosomal stability and condition were not significantly affected. The suite of interrelated biomarkers used offers a weight of evidence approach for demonstrating adverse effects of metal tissue accumulation in T. deltoidalis and A. trapezia

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25

Wijeyaratne, Dimuthu Nilmini. "Multi-Element Fingerprinting of River Sediments to Identify Diffuse Pollution Sources." Diss., North Dakota State University, 2011. https://hdl.handle.net/10365/28842.

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This study was carried out in the Souris and Turtle Rivers in North Dakota. The aim of this study was to develop multi-element fingerprints of the Souris River and Turtle River sediments and to evaluate the suitability of these fingerprints to assess the geographic origin of potential pollutants of the two rivers. Preliminary analysis of Souris River sediment samples confirmed that the multi-element fingerprinting can be used to assess the sediment and contaminant loading patterns. Laboratory experiments were performed to assess the validity of linear mixing assumption in multi-element fingerprinting studies. The results of these experiments verified the assumptions and showed that there is a statistically significant spatial and temporal variation in the element concentrations depending on their mobility and re-deposition. Field studies were conducted in the Souris River and Turtle River to assess the variation of element concentrations in the top riverbed samples along the main rivers and their tributaries. The sediment contribution from the tributaries and the phosphorus concentrations in the main channel were used to calculate the phosphorus contributions from the tributary sediments to the Souris River. The differences in phosphorus contributions from tributaries were related to land use, underlying geology, and the size of the watersheds of the tributaries in the Souris River watershed. Similar analysis was used in the Turtle River to calculate Arsenic, Cadmium and Selenium contribution from the tributaries to the Turtle River. The differences in the contribution of these elements were related to the underlying geology and the size of the watersheds. This study provides a detailed analysis of element concentrations and relative sediments and element loading rates from the tributaries to the main rivers along the Souris and Turtle Rivers in North Dakota. The multi-element fingerprinting technique can be successfully used as a tool to identify the relative contribution of sediments and assessing and tracing pollution sources in rivers. Multi-element fingerprinting provides a relatively low cost, rapid tool for sediment tracking, without the need for addition of exotic chemicals such radio-tracers or dyes to natural ecosystems.
North Dakota State University. College of Science and Mathematics
North Dakota State University. Department of Biological Sciences. Environmental Conservation Sciences Program
North Dakota Department of Health
ND INBRE
North Dakota Water Resources Research Institute
North Dakota State Water Commission

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26

Nobre, Maria Elisangela da Silva. "HidroquÃmica do aquifero aluvionar do baixo Jaguaribe ItaiÃaba-CearÃ." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=12830.

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CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior
No interior do Estado do CearÃ, as Ãguas subterrÃneas sÃo consideradas fontes preciosas de abastecimento hÃdrico e, as principais fontes de exploraÃÃo hÃdrica sÃo as Ãreas sedimentares e aluvionares. A pesquisa foi realizada no municÃpio de ItaiÃaba, inserido na Bacia HidrogrÃfica do Baixo Jaguaribe, onde a populaÃÃo, embora, provida de recursos da CAGECE, utiliza da captaÃÃo de Ãgua subterrÃnea para seu abastecimento hÃdrico, principalmente, na subsistÃncia da agricultura e pecuÃria. A regiÃo apresenta extensas Ãreas de carcinicultura, o que pode acarretar problemas ao meio ambiente, como a eutrofizaÃÃo, alteraÃÃo estrutural de comunidades biolÃgicas e contaminaÃÃo por metais pesados. Os objetivos principais desta pesquisa foram obter anÃlises: bacteriolÃgica, dos elementos maiores e menores, os primeiros dados sobre metais traÃos (Al, Ba, Cr, Ni, Mn e Pb) do municÃpio, isÃtopos de O18, balanÃo hÃdrico e vulnerabilidade. A metodologia consistiu na coletada de 21 amostras em trÃs campanhas, abrangendo perÃodos de estiagem e chuva, entre os anos de 2012 e 2013. As tÃcnicas empregadas corresponderam a mÃtodos potenciomÃtricos, espectrofotomÃtricos, titulomÃtricos, espectrometria de absorÃÃo atÃmica e de contagem em placa, basicamente, referenciadas pelo Standard Methods e, classificadas segundo os padrÃes da ResoluÃÃo no357/05 do CONAMA e da Portaria no 2914/11, do MinistÃrio da SaÃde. Segundo interpretaÃÃo analÃtica, detectaram-se bactÃrias coliformes na segunda e terceira campanhas; O pH das amostras estiveram entre 6,1 â 8,5, exceto para o poÃo 9 (pH=3,9), cuja acidez contribuiu para altos Ãndices do alumÃnio neste ponto; a condutividade variou entre 307 e 5940 ÂS/cm; as Ãguas se classificaram como Cloretadas SÃdicas; estÃo acima do padrÃo de potabilidade os seguintes teores: cloreto, em 33% das amostras; STD, < 62%; turbidez, 70%; nitrato, mÃdia de 33%; e, o ferro, em 19%. Encontrou-se a presenÃa de alumÃnio, bÃrio, chumbo, manganÃs e nÃquel, nas amostras. Segundo O18, no rio hÃ influÃncia marcante da evaporaÃÃo, inclusive de tanques de carcinicultura e, que alguns poÃos captam Ãgua de aquÃfero profundo e, outros da mistura entre aquÃfero, rio e chuvas, nÃo acompanhando a variaÃÃo sazonal. O balanÃo hÃdrico mostrou-se positivo para meses de alta pluviometria, mantendo-se o dÃficit hÃdrico para os outros meses do ano; Classificou-se o aquÃfero como de mÃdia a alta vulnerabilidade Ã contaminaÃÃo, pela metodologia GOD; Concluiu-se que a maioria dos poÃos continua apresentando resquÃcios de intervenÃÃo antrÃpica, inclusive da carcinicultura, sendo imprÃpria a sua potabilidade pelo risco de trazer prejuÃzos ao organismo.
In upstate of CearÃ, groundwater is considered precious sources of water supply, and the main sources of water exploration in sedimentary and alluvial areas. The research was conducted in the village of ItaiÃaba, inserted in the Baixo Jaguaribe Hydrographic Basin, where the population, though, resourced CAGECE uses the abstraction of groundwater for its water supply, mainly in subsistence agriculture and livestock. The region has extensive areas of shrimp farming, which can cause problems to the environment, such as eutrophication, structural changes in biological communities and heavy metal contamination. The main objectives of this research were to provide analyzes: bacteriological, major and minor elements, the first data on trace metals (Al, Ba, Cr, Ni, Mn and Pb) in the municipality, the O18 isotopes, fluid balance and vulnerability. The methodology consisted of 21 samples collected in three campaigns, including periods of drought and rain, between the years 2012 and 2013. The techniques used correspond to potentiometric methods, spectrophotometric, titrimetric, atomic absorption spectrometry and plate count basically referenced by Standard Methods and classified according to the standards nÂ 357/05 CONAMA Resolution and Ordinance nÂ 2914/11, the Ministry of Health. According to analytical interpretation, coliform bacteria were detected in the second and third sampling; The pH of the samples were between 6.1 to 8.5, except for P9 (pH = 3.9), whose acidity contributed to high levels of aluminum at this point; conductivity ranged between 307 and 5940 ÂS/cm; the waters are classified as Sodic Chlorinated; are above the standard of potability the following contents: chloride in 33% of samples; STD, <62%; turbidity, 70%; nitrate, an average of 33%; and iron, 19%. It was found the presence of aluminum, barium, lead, manganese and nickel in samples. According to O18 in the river there is a marked influence of evaporation, including the shrimp farming tanks and some wells capture water of deep aquifer, and others mix between aquifer, river and rain did not follow the seasonal variation. The water balance was positive for months of high rainfall, keeping the water deficit for the other months of the year; Aquifer was classified as medium to high vulnerability to contamination, by the methodology GOD; It was concluded that most of the wells continues to showing traces of human intervention, including the shrimp farming, being inappropriate for its potability risk of harm the organism.

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Johansson, Linn. "Trace Element Levels in Scalp Hair from Adolescents in Río Negro, Argentina : Link to Environmental and Dietary Factors." Thesis, Linnéuniversitetet, Institutionen för naturvetenskap, NV, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-16048.

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This study provides an insight into a provincial region of a developing country, namely Río Negro, Argentina and possible links between diet, environmental factors (especially water quality) and human health. Measuring levels of trace elements in scalp hair is a known method for assessing nutritional status. Levels of Ca, Fe, Mg, K, Na, As, Cr, Co, Cu, I, Mn, Mo, Ni, Se, V, Zn, Al, Cd, Pb, Rb and Hg in scalp hair from adolescents of the age 14 to 18 years in a rural and an urban population of Río Negro were analysed by inductively coupled plasma mass spectroscopy (ICP-MS). The hypothesis is that levels of trace elements reflect lifestyle factors such as smoking, beverage and food selection and consumption patterns and are directly linked to dehydration and could be associated with future health problems. Furthermore, environmental factors, such as (i) indecent water systems and governmental subsidised food in the rural/urban population, and (ii) ingestion or inhalation of arsenic (from naturally high sources of water, dust and foodstuffs) may also be linked to present and future health problems. The relationship between environmental and dietary factors could be implicated with the onset of diseases such as diabetes type II, obesity or hypothyroidism. The results show that both study populations in the region are exposed to several trace elements in exceedingly high amounts such as As and Mn through tap water which may induce cancers. Also, regular soft drink consumption is associated with low Cr level in this population. Evidence was not obtained for assessing potential dehydration. In terms of understanding the relationship between these factors, methods for assessing dehydration and dietary consumption need to be perfected, and other demographic issues and methods for quantifying obesity and health status will require further research.

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28

Siaka, I. Made, of Western Sydney Nepean University, and Faculty of Science and Technology. "The application of atomic absorption spectroscopy to the determination of selected trace elements in sediments of the Coxs River Catchment." THESIS_FST_XXX_Siaka_I.xml, 1998. http://handle.uws.edu.au:8081/1959.7/238.

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An investigation of heavy metal concentrations in sediments from Coxs River catchment, a tributary of the Hawkesbury-Nepean River system, has been undertaken. A number of digestion methods were assessed for the determination of Pb, Cu, Cd, Zn, Ni, Mn, Fe, Co and Cr in reference materials by flame AAS. The method that produced the best recovery is reverse aqua regia, HNO3-HC1 with ultrasonification followed by heating on a hotplate. Based on analysis of sediments from 133 sites, background concentrations were established. Elevated heavy metal concentrations were recorded in some samples. The three most polluted areas were investigated for heavy metal associations and distributions. Metal bioavailability was assessed from sediment samples by using selective extraction techniques. The association of heavy metals with different solid phases was assessed by a sequential extraction technique involving a series of extraction reagents. Pd, Cu, Fe and Cr were mainly associated with Fe/Mn oxides and organic matter plus sulphide phases. While Cd, Zn, Ni and Co which behave similarly were extracted from each step, the largest percentages of these metals were found in Fe/Mn oxides and organic matter phases. Mn was different to other metals, in that it predominantly associated with the ion exchangeable form.
Master of Science (Hons)

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29

Whitmore, Keridwen McLeyne. "Selenium Dynamics in Headwater Streams of the Central Appalachian Coalfields: An Investigation of Enrichment and Bioaccumulation." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/74955.

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Surface coal-mining is a source of selenium (Se) contamination in streams of the Appalachian coalfields. Selenium dynamics in aquatic systems are complex and largely controlled by site-specific factors, but have been understudied in Appalachian headwater streams. In this study, we evaluated the degree and dynamics of Se enrichment and bioaccumulation in headwater streams influenced by coal-mining. Based on Se concentrations in macroinvertebrates collected from 23 headwater streams, nine sites were selected for further study: three reference streams with no history of coal-mining, and six streams influenced by coal mining. Mining-influenced streams were further separated into high-Se and low-Sestreams based on macroinvertebrate tissue Se concentrations. Water-column, sediment, biofilm, leaf detritus, and prey and predator macroinvertebrates were collected and analyzed for Se concentration during two sample periods, Sept. - Oct. 2015 and Feb.-March 2016. Selenium concentrations in all media were found to be elevated in mining-influenced over reference streams and in high-Se over low-Se streams. Selenium dynamics, enrichment in particulate media (sediment, biofilm and leaf detritus) and trophic transfer of Se to prey from particulate media and to predators from prey, did not exhibit major differences among streams of differing Se levels. Water column Se concentrations were predicative of Se concentrations in macroinvertebrate tissues. Findings from this study indicate headwater streams influenced by coal-mining are capable of a high degree of Se bioaccumulation in macroinvertebrate populations.
Master of Science

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30

Vesk, Peter A. (Peter Anton). "Trace Metal Accumulation by Water Hyacinth, Eichhornia crassipes (Mart.) Solms, from Kensington Pond, Centennial Park, Sydney." Thesis, The University of Sydney, 1997. https://hdl.handle.net/2123/27621.

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Trace metal accumulation from urban stormwater run-off by a freefloating aquatic macrophyte, water hyacinth, Eichhornia crassipes (Mart) Solms, was studied in Kensington Pond, Centennial Park, Sydney. Two aspects of accumulation were investigated: - spatial variation of copper and lead concentrations among plants (and plant parts and sediment) throughout the wetland, using atomic absorption spectrometry of acid-digests; - metal distribution within the roots, using electron microscopy and Xray microanalysis. Copper and lead concentrations of roots ranged over an order of magnitude through the wetland, and considerable variation at the scale of individual plants was found. Samples of single or few plants are therefore unlikely to allow assessment of the pollution status of a wetland. Copper and lead had similar spatial distribution, although lead concentrations were higher than copper concentrations for plant roots and sediment. Metal concentrations in the sediments, roots and leaves declined exponentially with increased distance from the inflow to the wetland, explaining up to 87% (lead in roots) of the variation. The decline in metal concentration over distance was steeper for roots than sediments. Concentrations of metals were greater for fine secondary roots than for coarse primary roots. Regressions of loge transformed metal concentrations of roots and leaves on loge transformed metal concentrations in adjacent sediment were significant for copper in leaves and roots, and highly significant for lead in roots. X-ray microanalytical study of copper, lead, zinc and iron localization within secondary roots of water hyacinth demonstrated substantial metal concentrations within roots (confirming the value of X— ray microanalysis for environmental metal levels). Levels of trace metals, copper, lead and zinc, were higher inside the root than outside, with an increasing gradient towards the root centre. Copper and lead levels were generally higher within cells than in cell walls. Iron levels contrasted with trace metals, being higher in cell walls than within cells, and decreasing towards the centre of the root. Variation was high, suggesting that small— scale, lab—based studies may have limited applicability to the field. Multivariate statistical analyses were useful in elucidating patterns in localization of metals and relationships among different elements, and are recommended for further studies in X—ray microanalysis.

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31

Marozas, Dianne Catherine. "The effects of mineral reactions on trace metal characteristics of groundwater in desert basins of southern Arizona." Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/191127.

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The geochemistry, of groundwater collected from deep wells in the western section of the lower Santa Cruz basin of southeastern Arizona, was studied in order to determine the extent to which geochemica] analysis can be used to assess fluid flow and major and trace element migration patterns along hydrologic flowpaths in desert basins. Interaction between groundwater and enclosing sediments, and mixing between chemically distinct basin groundwater is found to exert a significant control on the chemical patterns that have evolved in the system. Activity-activity diagrams of the Na-Si-O-H system show that groundwater throughout the basin clusters near the three phase boundary between fluid, kaolinite, and montmorillonite and trends along the boundary to higher log (aNa⁺/aH⁺) values. A reaction model generated with computer program PHREEQE, that combines silicate weathering, kaolinite-Na-beidellite equilibrium, calcite equilibrium, and solution mixing, can simulate trends in groundwater composition along flowpaths in the basin. Trace metals introduced into the basin by the weathering of a buried porphyry copper deposit become spatially separated upon migration. Metal concentrations are found to be correlated to major cation concentrations. Cu is associated with high Na concentrations and a high ratio of Carbonate:Ca, whereas Zn is associated with high Ca concentration and a low ratio of Carbonate:Ca. Behavior of Cu and Zn during low-temperature transport can be controlled by the effects of mineral alteration on groundwater composition. Computer analysis of early basin diagenesis shows that changes in major solute composition that accompany weathering, constrained by equilibrium with clays and calcite, can produce the metal segregation pattern observed in the basin. Because the aquifer is strongly influenced by silicate and carbonate mineral equilibrium, the introduction of Central Arizona Project recharge, which is not in equilibrium with alluvial minerals, into the basin, requires a response by mineral reactions that attempt to restore the system to a state of equilibrium with kaolinite, montmorillonite, and calcite. A reaction model is developed to predict the consequent effects of outside recharge on groundwater quality.

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32

Ramjuttun, Ravindlall. "The chemical speciation of chromium in seawater by Cathodic stripping voltammetry." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0018/NQ47509.pdf.

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33

BRITO, CARLOS F. de. "Avaliação dos efeitos da construção do rodoanel na qualidade da água e sedimento da Represa do Parque Pedroso, Santo André, SP. Estudo geoquímico de hidrocarbonetos policíclicos aromáticos (HPAs) metais e elementos traço com vistas ao abastecimento público." reponame:Repositório Institucional do IPEN, 2014. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11806.

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Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2014-11-10T12:11:25Z No. of bitstreams: 0
Made available in DSpace on 2014-11-10T12:11:25Z (GMT). No. of bitstreams: 0
Tese (Doutorado em Tecnologia Nuclear)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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34

Cianciolo, Thomas Raymond. "Temporal and longitudinal extent of surface coal mining influences on water quality and benthic macroinvertebrate communities in central Appalachian headwater streams." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/90282.

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Increased loading of dissolved ions (salinization) and trace elements from surface coal mining is a common alteration to headwater streams in the central Appalachian region. However, temporal and spatial trends of water quality and associated influences on biota in these stream systems have not been well-studied. To address this research need, I analyzed temporal trends in specific conductance, ion matrix, and benthic macroinvertebrate communities in 24 headwater streams, including 19 influenced by surface mining, from 2011-2019. There was limited evidence of recovery of water chemistry or macroinvertebrate communities in these streams, indicating lasting impacts from surface coal mining. Among benthic macroinvertebrates, Ephemeroptera and the scraper functional feeding group were most-impacted by chronic salinization in study streams. In addition, I analyzed spatial patterns of water chemistry in a subset of these streams using synoptic sampling of multiple constituents under baseflow and highflow conditions. Study results indicate that water chemistry is spatially dynamic and can be influenced by both groundwater dilution and inputs from tributaries. Lastly, I investigated patterns in selenium bioaccumulation across and within streams, from particulate matter to top trophic levels (i.e. fish and salamanders). I found that benthic macroinvertebrates had the highest concentrations of selenium in these ecosystems, with lower concentrations in salamander and fish species. However, there was limited evidence of longitudinal trends in bioaccumulation dynamics downstream of mining impacts. Collectively, this work indicates long-term (ca. decades) coal-mining influences but also highlights future research needs to better understand downstream impacts to water quality and biotic communities.
Master of Science
Surface coal mining affects water quality in central Appalachian headwater streams. However, long-term and downstream patterns of impacted water quality and potential effects on aquatic life have not been well-studied. To address this research need, I analyzed trends in water quality parameters and aquatic insect communities in 24 headwater streams from 2011-2019. There was limited evidence of recovery of water chemistry or aquatic life in these streams, indicating lasting impacts from surface coal mining. Certain aquatic insects including Ephemeroptera (mayflies) appear to be more impacted than others by long-term altered water quality. In addition to trends over time, I also analyzed downstream variation in water chemistry in a subset of these streams under baseflow conditions and after a rain event. Results indicate that water chemistry can vary greatly within a stream network and is influenced by tributary inputs and dilution from groundwater. Concentrations of the trace element selenium can also be elevated as a result of surface mining. This is of environmental concern because selenium can biomagnify, where concentrations increase in organisms higher in the food chain and can cause toxic effects. Here, I investigated selenium bioaccumulation patterns across organisms in the food chain and with distance downstream across six headwater streams. I found that aquatic insects had the highest concentrations of selenium, with lower concentrations in salamanders and fish. This work indicates that surface coal mining has longterm (ca. decades) effects on headwater streams, but also points to future research to better understand downstream impacts to water quality and aquatic life.

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Peplow, Dan. "The influence of mine waste contamination on invertebrates and fish in the Methow River Valley, Okanogan County, Washington (U.S.A.) /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/5519.

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36

Shumskykh, Mykyta. "Release of trace elements from contaminated sediments into surface waters during sediments dynamics : an experimental study." Thesis, Tours, 2019. http://www.theses.fr/2019TOUR4008.

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Dans les systèmes aquatiques, la plupart des éléments traces métalliques (ETM) sont piégés dans les sédiments puis peuvent être relargués en fonction des conditions chimiques et de l’activité microbienne à l’interface eau-sédiment. L’objectif de cette étude était d’évaluer l’impact de remise en suspension des sédiments (lors de crues et d’opérations de gestion de barrages) sur la mobilité de certains ETM. Plusieurs conditions expérimentales de lessivage ont été choisies pour simuler ces événements : conditions oxiques et anoxiques sur des sédiments bruts et d’autres irradiés par rayons gamma. L’utilisation d’eau désionisée a permis de maximiser le processus de relargage. Deux types de sédiments, issus de contextes différents, ont été sélectionnés : le barrage de Villerest (France) et la rivière Xiang (Chine). Des expériences à long terme (30 jours) ont permis d’identifier la dégradation de la matière organique, l’activité microbienne et l’altération (voire la dissolution) de phases porteuses d’ETM comme principaux facteurs de contrôle. L’importance de l’activité microbienne n’a pas pu être quantifiée puisque l’irradiation n’a pas stérilisé totalement les sédiments. Enfin, l’impact de tels évènements parait très limité puisque moins de 1% des ETM contenus dans les sédiments ont été libérés
In aquatic systems, most of trace metals (TM) are buried in sediments and then can be released according to chemical conditions and microbial activity occurring at the sediment-water interface. The aim of this study was to assess the impact of resuspension events (flood or maintenance operations for dam reservoir) on the mobility of some TM. Different batch experiment conditions were chosen to mimic those events: under oxic and anoxic conditions on raw sediments and on gamma-irradiated ones (“sterilized” one). The use of deionized water allowed maximizing the release process. Two sediment types issued from different contexts were selected: the Villerest dam reservoir (France) and the Xiang River (China). Long term experiments (30-day long) allowed identifying that organic matter degradation, microbial activity and alteration/dissolution of trace metal bearing phases were the main controlling factors. The gamma-irradiation did not sterilize sediments but only limited aerobic bacteria and enhanced anaerobic activity. The impact of such 24h resuspension event on reservoir waters and downstream biota is very limited as less than 1% of trace elements was released

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PAVONI, ELENA. "TRACE ELEMENTS IN ESTUARINE ENVIRONMENTS: MIXING, PARTITIONING AND FATE IN THE MAIN ITALIAN AND SLOVENIAN RIVER MOUTHS (GULF OF TRIESTE, NORTHERN ADRIATIC SEA)." Doctoral thesis, Università degli Studi di Trieste, 2020. http://hdl.handle.net/11368/2963759.

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Gli estuari rappresentano complessi ambienti di transizione tra le terre emerse e le aree marino costiere. Nella zona di mescolamento tra acque fluviali e marine, le sostanze contaminanti potenzialmente veicolate dai corsi d’acqua sono soggette a svariati processi fisici, geochimici e biologici. Infatti, le condizioni chimico-fisiche di contorno, specialmente in termini di salinità, sono estremamente variabili nello spazio e nel tempo e concorrono alle complesse dinamiche sedimentarie degli ambienti di foce fluviale. Inoltre, i processi che avvengono nella zona di mescolamento svolgono un ruolo fondamentale nella regolazione degli equilibri tra la fase solida e quella disciolta. Per questi motivi, gli estuari sono spesso considerati trappole sedimentarie e fungono da filtro naturale per le sostanze contaminanti, inclusi elementi in tracce potenzialmente tossici. L’attività di ricerca comprende due argomenti principali. Il primo riguarda lo studio del partizionamento degli elementi in tracce (As, Cd, Co, Co, Cr, Cs, Cu, Fe, Hg, Mn, Ni, Pb e Zn) nel particellato in sospensione, nel materiale colloidale e nella frazione veramente disciolta. Questo aspetto è stato valutato nei principali ambienti estuarini del Golfo di Trieste: fiumi Isonzo, Timavo, Rižana e Dragonja. Ulteriori informazioni riguardo alla qualità delle acque sono state fornite dalla determinazione del carbonio organico disciolto e colloidale, azoto totale e nutrienti quali nitrati, nitriti, ammonio, silice reattiva e fosforo reattivo. I risultati evidenziano che il particellato in sospensione svolge un ruolo fondamentale nella distribuzione degli elementi in tracce, i quali spesso tendono ad essere partizionati nella fase solida. Generalmente, Cr, Cu, Fe, Fe, Hg, Ni e Pb sono preferenzialmente associati al particellato in sospensione e, al tempo stesso, mostrano una discreta affinità con il materiale colloidale. Al contrario, As e Cs sono preferibilmente presenti in forma disciolta, mentre maggiori differenze, in termini di partizionamento tra fase solida e disciolta, sono emerse nel caso di Co, Mn e Zn. Per quanto riguarda i nutrienti, la prevalenza dei nitrati, tra le forme dell’azoto inorganico, è riconducibile a processi di dilavamento da suoli interessati da attività agricole. Per quanto riguarda la generale qualità dell’acqua, il rapporto molare DIN:SRP indica che nelle foci fluviali dei fiumi Isonzo, Timavo e Dragonja prevalgono condizioni di P limitazione. Al contrario, condizioni di N limitazione sono state riscontrate in estate nel sistema estuarino del fiume Rižana, sebbene condizioni di P limitazione prevalgano in autunno e in inverno. Il secondo argomento indagato in questa ricerca riguarda il sistema estuarino del fiume Timavo, sede di diverse attività industriali. Allo scopo di fornire una caratterizzazione geochimico-ambientale, svariati elementi in tracce (Al, As, As, Ba, Cd, Co, Cr, Cs, Cu, Fe, Hg, Mn, Ni, Pb, V e Zn) sono stati determinati in diverse matrici ambientali (acqua, particellato in sospensione e sedimenti) così come carbonio organico disciolto, azoto totale e nutrienti. L’analisi delle componenti principali è stata utilizzata allo scopo di valutare eventuali differenze tra i diversi settori dell’area di studio, mettendo in luce le maggiori criticità dal punto di vista ambientale. Nel settore più interno, i sedimenti sono risultati arricchiti in diversi elementi in tracce e potenziali effetti ecotossicologici per gli organismi bentonici sono emersi nel caso di Ni e Hg. Inoltre, condizioni di solfato-riduzione all’interfaccia acqua-sedimento potrebbero favorire la precipitazione di solfuri con conseguente accumulo di elementi in tracce nella frazione residuale del sedimento. Tuttavia, si suppone che ossidi e idrossidi di Fe e Mn svolgano un ruolo fondamentale nella regolazione delle concentrazioni disciolte di elementi in tracce lungo la colonna d’acqua.
Estuaries are complex aquatic systems at the land-sea interface where the interaction between different water masses leads to strong physico-chemical gradients. Before reaching the coastal zone, the river-transported material must pass through the estuarine environment. In this context, estuaries act as a filter for the freshwater inputs of both dissolved and particulate components. The original river-transported original signals can then emerge from the mixing zone in a form which has been notably modified with respect to that which entered the estuarine system. Trace element distribution, mobility and fate heavily depends on the physical, geochemical and biological processes occurring in the estuarine mixing zone, which also affect the equilibria between solid and dissolved phases. The study of trace element phase partitioning is essential to gain a thorough knowledge of their natural cycles, although significant alterations may be due to the high anthropogenic pressure that often affects estuarine environments. This research includes two main topics. The first concerns trace element (As, Cd, Co, Cr, Cs, Cu, Fe, Hg, Mn, Ni, Pb and Zn) phase partitioning in the main estuarine environments of the Gulf of Trieste (northern Adriatic Sea). In detail, estuarine water samples were collected at the Isonzo/Soča, Timavo/Reka, Rižana and Dragonja River mouths under different seasonal conditions and size fractionation allowed for the isolation of three fractions: suspended particulate matter, colloidal material and the truly dissolved fraction. Further information regarding the investigated estuarine systems was provided by dissolved and colloidal organic carbon, total nitrogen and nutrients including nitrate (N-NO3-), nitrite (N-NO2-), ammonium (N-NH4+), soluble reactive silicate (SRSi) and soluble reactive phosphorous (SRP). Suspended particulate matter plays a crucial role as the main vehicle of trace elements from terrestrial sources to marine coastal areas. Generally, Cr, Cu, Fe, Hg, Ni and Pb are mainly partitioned in the suspended particles and partially bound to the colloidal material. Conversely, As and Cs are preferably associated with the truly dissolved fraction, whereas major differences are observed in the partitioning behaviour of Co, Mn and Zn. Colloidal organic carbon is found to be scarcely present at the river mouths, since the hydrodynamic conditions may weaken the aggregation of very fine particles, thus suggesting that colloids play a minor role. Regarding nutrients, N-NO3- prevails among the forms of dissolved inorganic nitrogen as a result of runoff from soils where agricultural activities take place. In terms of water quality, the DIN:SRP molar ratio indicates that P-limitation prevails at the Isonzo/Soča, Timavo/Reka and Dragonja River mouths. Conversely, the Rižana estuarine system switches from P-limitation, prevailing in autumn and winter, to N-limitation in summer. The second topic of this research is focused on the karstic estuarine system of the Timavo/Reka River where several industrial activities are located. In order to provide a geochemical characterisation, trace elements (Al, As, Ba, Cd, Co, Cr, Cs, Cu, Fe, Hg, Mn, Ni, Pb, V and Zn) were measured in different environmental matrices (water, suspended particles and sediments) as well as dissolved organic carbon, total nitrogen and nutrients. Principal component analysis was employed to depict disparities among the different sectors of the estuarine system. In particular in the innermost sector, sediments were found to be enriched in trace elements and potential adverse ecotoxicological effects were identified for Ni and Hg. Moreover, potential anoxic conditions at the sediment-water interface suggest that removal of trace elements via sulphide precipitation could occur although recycling of sinking Fe and Mn-oxy-hydroxides appears to affect dissolved trace element concentrations in the anoxic water layer.

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Chen, Heidi Haiqing. "Development of flow injection on-line precipitation-dissolution coupled with inductively coupled plasma mass spectrometry for the determination of trace elements in saline water." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ63411.pdf.

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39

Soares, Wálace Anderson Almeida. "Estudo da distribuição de metais em água, sedimento e organismos aquáticos de rios e reservatórios pertencentes à rede de monitoramento da qualidade dos sedimentos do Estado de São Paulo, Brasil." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-16012013-144500/.

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O presente trabalho teve como objetivo realizar um estudo dos níveis de concentração e da distribuição das espécies metálicas Arsênio, Cádmio, Crômio, Cobre, Níquel e Chumbo em água, sedimento e nos organismos bentônicos dos rios e reservatórios pertencentes à Rede de Monitoramento de água e sedimento da CETESB, utilizando as técnicas analíticas de espectrometria de absorção atômica com atomização em forno de grafite (GF AAS) e espectrometria de emissão ótica (ICP OES). Paralelamente, avaliou-se a toxicidade da água e do sedimento para a bactéria Vibrio fischeri e a comunidade bentônica local. A caracterização multielementar (concentração total) dos sedimentos pela técnica de análise por ativação neutrônica (NAA) também foi realizada. Todas as metodologias analíticas foram avaliadas quanto à precisão, exatidão e os limites de detecção e quantificação foram calculados. Nas amostras de água, foram obtidas concentrações dos metais analisados inferiores aos limites estipulados pela Resolução 357/2005 do CONAMA para corpos de água classe 2. Os elementos estudados foram determinados, muitas vezes em concentrações que podem causar efeitos adversos à biota aquática, nas amostras de sedimento de dez dos treze pontos estudados, o que sugere que estes elementos tendem a se depositar nos sedimentos. Obtiveram-se concentrações dos elementos Cd, Cu, Pb e Ni em muitas das amostras de invertebrados bentônicos estudados, demonstrando que estes elementos podem ser absorvidos e bioacumulados nos organismos expostos aos sedimentos contaminados. A correlação entre as concentrações dos elementos no sedimento e nos organismos foi significativa e positiva. As correlações entre as concentrações dos elementos detectados e a massa dos organismos também foram significativas, porém negativas, ou seja, quanto menor a massa, maiores concentrações são esperadas. Não foi detectada toxicidade aguda nas amostras de água para o Vibrio fischeri, porém foi detectada na água intersticial de oito das treze amostras de sedimento testadas. Quanto à avaliação da comunidade bentônica, um ponto foi classificado como qualidade Ruim, oito como Regular e quatro como Boa, segundo critério adotado pela CETESB. Os resultados obtidos na análise de sedimentos por análise por ativação neutrônica demonstraram existir valores mais enriquecidos para os elementos As, Br, Cr, Hf, Ta, Th , U e Zn e os elementos terras raras (ETR) Ce, Eu, La, Nd, Sm, Tb e Yb em muitas das amostras analisadas indicando que pode estar havendo contribuição antrópica para esses elementos.
The present study analyzed concentration levels and distribution of As, Cd, Cr, Cu, Ni and Pb metallic species in water, sediment and aquatic organisms in rivers and reservoirs of a water and sediment quality monitoring network belonging to CETESB. For this purpose two analytical techniques Graphite Furnace Atomic Absorption Spectrometry (GF AAS) and Optical Emission Spectrometry with Inductively Coupled Plasma (ICP OES) were used. Water and sediment toxicity for Vibrio fischeri bacteria and the local benthic community were also evaluated. The multielemental characterization of sediments was undertaken by neutron activation analysis technique (NAA). All the analytical methodologies were evaluated for precision and accuracy, and detection and quantification limits calculated. In water samples metal concentrations were below the CONAMA 357/2005 resolution limits for class 2 water bodies. For sediment samples metal concentration levels that can cause adverse effects on aquatic biota were found in 10 of the 13 collection points studied. Metals Cd, Cu, Pb and Ni were detected in many invertebrate benthic organisms samples studied, indicating that these elements can be absorbed and bioaccumulated by these organisms when exposed to contaminated sediments. Significant correlations were found for metal concentrations in sediments and organisms. Negative correlations between detected element concentrations and weight of the sampled organisms were significant, so that the lower the weight the higher metal concentrations were measured. Acute toxicity for Vibrio fischeri was not observed for the water samples, but was detected in 8 of the 13 sediment interstitial water samples tested. As for the benthic community evaluation, one of the 13 points was rated as BAD quality, 8 rated as REGULAR and 4 as GOOD, using CETESB´s classification. The results for sediment samples by NAA showed higher enrichment values for As, Br, Cr, Hf, Ta, Th , U e Zn and rare earth elements (REE) Ce, Eu, La, Nd, Sm, Tb and Yb in many of the tested sediment samples indicating that there may be and anthropic contribution for these elements.

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Havia, J. (Johanna). "Trace element analysis of humus-rich natural water samples:method development for UV-LED assisted photocatalytic sample preparation and hydride generation ICP-MS analysis." Doctoral thesis, Oulun yliopisto, 2017. http://urn.fi/urn:isbn:9789526216812.

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Abstract Humus-rich natural water samples, containing high concentrations of dissolved organic carbon (DOC), are challenging for certain analytical methods used in trace element analysis, including hydride generation methods and electrochemical methods. In order to obtain reliable results, the samples must to be pretreated to release analytes from humic acid complexes prior to the determination. In this study, methods for both pretreatment and analysis steps were developed. Arsenic is a toxic element and therefore its determination even at low concentration levels is important in environmental monitoring. Arsenic complexed with humic substances is not likely to form volatile hydrides quantitatively during borohydride reduction. In this study, natural water samples were digested with microwave-assisted digestion method prior to analysis by hydride generation inductively coupled plasma mass spectrometry (HG-ICP-MS). In addition, a dual mode sample introduction system was used to study internal standardization in order to correct signal variations during the measurement of arsenic with HG-ICP-MS. A novel nano-TiO2 catalyzed ultraviolet light emitting diode (UV-LED) digestion device was developed to apply green chemistry principles in sample preparation. The method consumes less harmful reagents and less energy than traditional techniques. The DOC removal efficiency was studied as a function of pH, irradiation time and hydrogen peroxide concentration. Recoveries of spiked heavy metals and hydride forming elements were studied. UV-LED technology is growing rapidly, and new catalytic semiconductor materials for photocatalysis are being developed. In this study, the effects of synthesis method variables on the properties of ZnO nanopowders were investigated
Tiivistelmä Luonnonvesinäytteet voivat sisältää suuria määriä liuennutta hiiltä (DOC), jolloin pienten alkuainepitoisuuksien määrittäminen voi olla haasteellista esimerkiksi hydridinmuodostusmenetelmillä ja sähkökemiallisilla menetelmillä. Luotettavien tulosten saavuttamiseksi näytteet täytyy esikäsitellä analyyttien vapauttamiseksi humushappokomplekseista ennen määrityksiä. Tässä tutkimuksessa kehitettiin menetelmiä humuspitoisille luonnonvesinäytteille sekä esikäsittelyvaiheeseen että analyysivaiheeseen. Arseeni on myrkyllinen alkuaine, jonka määrittäminen pienissä pitoisuuksissa on ympäristön seurannan kannalta tärkeää. Humusyhdisteisiin kompleksoitunut arseeni ei muodosta kvantitatiivisesti hydridejä borohydridipelkistyksellä. Tässä tutkimuksessa luonnonvesinäytteet hajotettiin mikroaaltoavusteisella hajotusmenetelmällä ennen arseenin mittaamista hydridinmuodostus-induktiiviplasmamassaspektrometrialla (HG-ICP-MS). Tämän lisäksi tutkittiin mittaustarkkuuden parantamista sisäisellä standardoinnilla mitattaessa arseenia HG-ICP-MS-menetelmällä. Tutkimuksessa kehitettiin myös uudenlainen näytteenkäsittelylaitteisto, jossa käytettiin säteilylähteenä ultraviolettivaloa emittoivaa diodia (UV-LED) ja katalyyttinä nanotitaanidioksidia. Uusi ympäristöystävällinen menetelmä kuluttaa vähemmän haitallisia reagensseja ja vähemmän energiaa kuin perinteiset menetelmät. Kehitetyn menetelmän hajotustehokkuutta tutkittiin pH:n, säteilytysajan ja vetyperoksidikonsentraation funktiona. Lisäksi raskasmetallien ja hydridiä muodostavien alkuaineiden saantoja tutkittiin lisäyskokeilla. UV-LED-teknologia kehittyy nopeasti ja uusia valokatalyysimateriaaleja tutkitaan jatkuvasti. Tässä tutkimuksessa tarkasteltiin synteesimuuttujien vaikutusta sinkkioksidinanojauheiden ominaisuuksiin

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41

van, Schaik Joris W. J. "Binding of metals to macromolecular organic acids in natural waters : does organic matter? /." Uppsala : Department of Soil and Environment, Swedish University of Agricultural Sciences, 2008. http://epsilon.slu.se/200872.pdf.

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42

Poulier, Gaelle. "Etude de l’échantillonnage intégratif passif pour l’évaluation réglementaire de la qualité des milieux aquatiques : application à la contamination en pesticides et en éléments trace métalliques des bassins versants du Trec et de l’Auvézère." Thesis, Limoges, 2014. http://www.theses.fr/2014LIMO0032/document.

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Parce qu’ils sont peu coûteux, faciles d’utilisation, et surtout très efficaces, les pesticides sont devenus une composante majeure de l’agriculture moderne et se sont imposés dans de nombreuses activités urbaines et domestiques. Ces molécules se retrouvent aujourd’hui dans tous les compartiments de l’environnement notamment dans les milieux aquatiques. Le suivi resserré des substances actives et de leurs résidus, présents dans l’environnement à des concentrations potentiellement dommageables pour les écosystèmes, apparaît aujourd’hui comme une nécessité. L’application de la Directive cadre sur l’eau, l’une des principales réglementations européenne ciblant les eaux, requiert des techniques d’échantillonnage et d’analyse performantes, alliant haute sensibilité, facilité de mise œuvre, coûts abordables, et surtout précision et fiabilité. Actuellement, la méthodologie employée consiste en des prélèvements ponctuels d’eau à pas de temps lâche (une fois par mois en général) suivi de l’analyse en laboratoire. Cette approche souffre d’un manque de représentativité temporelle, couplée à une sensibilité analytique souvent peu satisfaisante. Les techniques d’échantillonnage passif développées au cours des 20 dernières années pourraient être intégrées dans les réseaux de surveillance réglementaires afin de pallier ces manques, mais des questions subsistent encore quant à leur opérationnalité. Ces travaux de thèse visent à développer puis tester les échantillonneurs passifs sur le terrain afin de déterminer leur adéquation avec les exigences de la Directive cadre sur l’Eau, et le cas échéant, mettre en évidence les principaux verrous scientifiques résiduels. L’originalité de ce travail réside dans:- la variété des outils évalués : trois échantillonneurs différents ont été étudiés (Le Polar Organic Chemical Integrative Sampler (POCIS), le Chemcatcher et le Diffusive Gradient in Thin film (DGT). Les méthodes classiques de prélèvement ponctuels ont également été mise en œuvre.- la variété des environnements étudiés : deux bassins versant très différents ont été considérés, l’un présentant une contamination en pesticides forte, l’autre une contamination modérée.- La mise en en œuvre des échantillonneurs passifs dans un réel contexte réglementaire, les cours d’eau choisis faisant l’objet d’un contrôle opérationnel. Les données acquises avec les échantillonneurs passifs ont ainsi pu être comparées avec les suivis de l’Agence de l’Eau
The intensive use of pesticides in agriculture and urban activities since the 1950s has led to diffuse contamination of environmental compartments (air, soil, water). The presence of these molecules can lead to toxic effects for biota. The implementation of the Water Framework Directive (WFD) requires the use of an efficient monitoring network, based on reliable sampling and analytical techniques. Nowadays, grab sampling followed by extraction of analytes and chromatographic analysis is the most widespread strategy because of its simplicity of implementation but it also has numerous drawbacks. The crux of the issue lies in the lack of temporal representativeness and the low analytical sensibility. An alternative strategy to overcome some of these problems could be the use of passive samplers. This contribution aims at discuss about the possible application of passive samplers in regulatory monitoring programs. The originality of this work lies in :The variety of tested devices: three different samplers was studied (The Polar Organic Chemical Integrative Sampler (POCIS), the Chemcatcher and the Diffusive Gradient in Thin Film (DGT). Conventional grab sampling strategies were also evaluated.The variety of studied environments: two very different watersheds were selected. The first one presented a high level of contamination; the second had a low contamination in pesticides.The implementation of passive samplers in a real regulatory context, as the selected streams were monitored by the Water Agency for operational control. Data from the Water Agency could therefore be compared with passive sampler data

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43

Siaka, I. Made. "The application of atomic absorption spectroscopy to the determination of selected trace elements in sediments of the Coxs River Catchment." Thesis, View thesis, 1998. http://handle.uws.edu.au:8081/1959.7/238.

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An investigation of heavy metal concentrations in sediments from Coxs River catchment, a tributary of the Hawkesbury-Nepean River system, has been undertaken. A number of digestion methods were assessed for the determination of Pb, Cu, Cd, Zn, Ni, Mn, Fe, Co and Cr in reference materials by flame AAS. The method that produced the best recovery is reverse aqua regia, HNO3-HC1 with ultrasonification followed by heating on a hotplate. Based on analysis of sediments from 133 sites, background concentrations were established. Elevated heavy metal concentrations were recorded in some samples. The three most polluted areas were investigated for heavy metal associations and distributions. Metal bioavailability was assessed from sediment samples by using selective extraction techniques. The association of heavy metals with different solid phases was assessed by a sequential extraction technique involving a series of extraction reagents. Pd, Cu, Fe and Cr were mainly associated with Fe/Mn oxides and organic matter plus sulphide phases. While Cd, Zn, Ni and Co which behave similarly were extracted from each step, the largest percentages of these metals were found in Fe/Mn oxides and organic matter phases. Mn was different to other metals, in that it predominantly associated with the ion exchangeable form.

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Brough, Kate Elizabeth. "Studies of Brisbane municipal water quality using Inductively Coupled Plasma - Mass Spectrometry and Chemometrics." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/79902/1/Kate_Brough_Thesis.pdf.

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This research established innovative methods and a predictive model to evaluate water quality using the trace element and heavy metal concentrations of drinking water from the greater Brisbane area. Significantly, the combined use of Inductively Coupled Plasma - Mass Spectrometry and Chemometrics can be used worldwide to provide comprehensive, rapid and affordable analyses of elements in drinking water that can have a considerable impact on human health.

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Munsel, Dirk [Verfasser], and T. [Akademischer Betreuer] Neumann. "Utilisation of trace element contents in benthic foraminifera for reconstructing sea water composition / Dirk Munsel. Betreuer: T. Neumann." Karlsruhe : KIT-Bibliothek, 2014. http://d-nb.info/1047383527/34.

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Balestri, Máira Renata Dias. "Avaliação da contaminação de Poecilia reticulata e Hypostomus ancistroides por elementos-traço na Bacia do Ribeirão Cafezal (Município de Rolândia - PR)." Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1902.

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A qualidade da água é um fator importante para o bem-estar do ser humano, e equilíbrio dos ecossistemas naturais. Com o aumento populacional e a consequente industrialização, se intensificou a produção de esgoto doméstico e de efluentes industriais, os quais podem conter metais e acentuar a poluição ambiental. Alguns elementos-traço são considerados essenciais para o desenvolvimento e manutenção dos organismos, porém, se forem ingeridos em concentrações acima das recomendadas, podem ser tóxicos. O objetivo desse estudo foi avaliar o grau de contaminação de duas espécies de peixes (Poecilia reticulata e Hypostomus ancistroides) abundantes do Ribeirão Cafezal (Rolândia - PR) pelos elementos Zn, Cd, Cr e Pb. A coleta dos peixes foi realizada em três pontos ao longo do trecho superior da bacia do Ribeirão Cafezal, utilizando os métodos de pesca elétrica e manual, com esforço amostral de 40 min para cada método. Para a detecção dos elementos traço no material coletado, as amostras foram devidamente preparadas para emprego da técnica de Espectrometria de Emissão Óptica por Plasma Indutivamente Acoplado (ICP-OES). As concentrações apresentadas pelos indivíduos da espécie Poecilia reticulata (pontos 1 e 2) amostrados do ribeirão foram: Zn (107,63; 91,89 mg/kg) , Cd (0,12; 0,42 mg/kg), Cr (2,17; 4,96 mg/kg) e Pb (0,71; 0,44 mg/kg); enquanto que para a espécie Hypostomus ancistroides (pontos 2 e 3) foram: Zn (93,11; 76,97 mg/kg), Cd (2,22; 0,10 mg/kg), Cr (16,05; 2,23 mg/kg) e Pb (2,83; não determinado mg/kg). Todos os valores estão acima dos limites permitidos pela ANVISA (Agência Nacional de Vigilância Sanitária). Não houve diferenças significativas nas concentrações dos metais entre os pontos de amostragem avaliados. Como se trata de um Ribeirão onde as pessoas utilizam a água para recreação e se alimentam dos peixes que colonizam o local, é preciso continuar a atividade de monitoramento, bem como realizar análises sistemáticas com diferentes espécies de peixes, água e sedimento.
Some trace elements are considered essential for the development and maintenance of living organisms. However, if those trace elements are ingested in higher concentrations than recommended can be toxic. The aim of this study was to evaluate the degree of contamination for two abundant species of fish from Ribeirão Cafezal (Poecilia reticulata and Hypostomus ancistroides) with Zn, Cd, Cr and Pb elements. The fish collection was performed at three points along the upper stretch of the basin of Ribeirão Cafezal using electric and manual fishing methods, with sampling effort of 40 minutes for each method. In order to detect the trace elements in the collected material, the samples were properly prepared to the Inductively Coupled Plasma by Atomic Emission Spectroscopy (ICP-OES). The concentrations presented by the species Poecilia reticulata in the two first points of the stream were: Zn (107.63; 91.89 mg / kg), Cd (0.12, 0.42 mg / kg), Cr (2.17; 4.96 mg / kg) and Pb (0.71, 0.44 mg / kg), sampled in 1 and 2 respectively. And individuals of Hypostomus ancistroides species sampled in points 2 and 3 had the following values: Zn (93.11; 76.97 mg / kg), Cd (2.22, 0.10 mg / kg), Cr (16.05; 2.23 mg / kg) and Pb (2.83; nd mg / kg). All values are higher than the limits allowed by ANVISA. There were no significant differences in the metals concentrations among the sampling points assessed. In consideration for Ribeirão Cafezal being a stream where people use water for recreation and feed on the existing fish, we need to continue monitoring it, as well as performing systematic analysis with different species of fish, sediment and water.

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Lord, Gillian M. "Arsenic and other trace elements in natural waters from Argentina and New Zealand: relationship between environmental exposure and human health." Thesis, University of Surrey, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.658999.

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Arsenic and other trace elements were analysed in natural waters and human biological samples (scalp hair, nails and blood serum) from the high-arsenic provinces of Santa Fe and San Juan in Argentina by inductively coupled plasma mass spectrometry (ICP-MS). Arsenic species were also analysed in waters from Santa Fe and Rio Negro (low-arsenic province) using a solid phase extraction (SPE) technique and evaluated in relation to pH and redox potential (Eh). In Santa Fe and San Juan the water arsenic levels typically exceeded the World Health Organisation (WHO) and Argentine standard for drinking water of 10 1lg/1 As, ranging 11.1 - 1050 and 1.49 - 14900 Ilg/1 As, respectively. The impact of this arsenic exposure was reflected in the hair (0.03 - 7.85 mg/kg As), fingernail (0 .08 - 16.7 mg/leg As) and toenail (0.07 - 21.1 mg/kg As) washed samples fi.-om Santa Fe, with statistically significant correlations (Speannan, P < 0.01) observed against the well water across the whole population. In contrast, no statistically significant correlations (at P < 0.05) were found between the samples from San Juan: hair, 0.01 - 241.7 mg/leg As; toenails: 0.04 - 0.55 mg/leg As, and; blood serum 0.26 - 721 ug/1 As. The relationship between arsenic exposure and the presence of a chronic health disorder, specifically type 2 diabetes mellitus (T2DM), was evaluated in both populations. The toenail arsenic levels in the healthy/control participants were significantly higher (Mann-Whitney U-test, P < 0.01), compared to those with a chronic health disorder, including T2DM. These differences were thought to be due to an improved arsenic metabolism in individuals with a high body mass index (BMI). Further differences were found for hair and blood serum, with significantly (P < 0.01) higher levels of arsenic observed in the samples from the T2DM population, suggesting a relationship between arsenic and T2DM. A number of statistically significant correlations were found between arsenic, selenium and vanadium in the biological samples from the control and T2DM groups. However, due to the complexity of T2DM, no conclusive relationships could be found between this disorder and arsenic. A further study was conducted on the geothermal waters from Copahue-Caviahue in Argentina and the Taupo Volcanic Zone (TVZ) in New Zealand. Analysis of the Upper Rio Agrio waters on Copahue volcano (466 - 614 1lg/1 As) indicated that the volcano could be a source of the arsenic contamination across Argentina. In addition, the geothermal waters in New Zealand highlighted a potential minor exposure route of dermal absorption which may affect bathers in these waters or individuals using high-arsenic ground or surface waters for self-washing in Argentina.

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48

Pregnolato, Leonardo Antonio. "Influência de efluentes petroquímicos nos sedimentos e carapaças de foraminíferos no Polo Atalaia, SE (Brasil)." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/100/100136/tde-10022018-140505/.

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Os objetivos do presente trabalho foram 1) avaliar a qualidade ambiental dos sedimentos ao redor do emissário submarino de efluentes petroquímicos tratados do Polo Atalaia, Sergipe e 2) fornecer elementos técnicos e científicos para aprimorar os estudos de biomonitoramento realizados na referida região. Para atingir estes objetivos foram realizadas análises granulométricas, geoquímicas (nutrientes, metais, metaloides, hidrocarbonetos) e da meiofauna (biocenoses e tanatocenoses de foraminíferos) de tréplicas de 19 amostras de sedimentos, coletadas ao redor do emissário (área experimental) e em uma área controle, situada a 5 km ao norte do emissário. Essas 57 amostras e seus respectivos dados abióticos foram cedidos pela Petrobras. A maior parte da área estudada é constituída por sedimentos lamoarenosos. Contudo, na área experimental há predominância dos termos lamosos, ricos em carbono orgânico e fósforo total. Na área controle, as porcentagens de areia muito fina são maiores e ocorrem elevados valores de nitrogênio total. As concentrações de Pb, Cr, Ni, Zn das duas áreas estudadas encontram-se abaixo do nível 1 do Conselho Nacional do Meio Ambiente (CONAMA) e ISQG (Interim Sediment Quality Guidelines), ou seja, os sedimentos não estão contaminados por esses elementos metálicos. Contudo, os valores de As estão entre os limites 1 e 2 do CONAMA e ISQG e PEL (probable effect level) em todas as estações, indicando que a biota pode ser afetada por esse elemento. Uma amostra (área experimental) apresenta valores de Cd, Cr e Hg entre os limites de ISQG e PEL e uma outra amostra (área controle) apresenta concentrações de Cr acima do nível 2 e PEL. Concentrações de hidrocarbonetos totais de petróleo (HTP), hidrocarbonetos resolvidos de petróleo (HRP) e de mistura complexa nãoresolvida (MCNR) são maiores na área experimental e em duas amostras da área controle. A composição da tanatocenose é muito diferente da biocenose, reforçando ao fato de que se deve utilizar principalmente organismos vivos em estudos de análise de impacto ambiental. O sedimento utilizado para a análise dos foraminíferos oscilou entre 20 e 110 cm3 para encontrar cerca de 100 indivíduos vivos. Percentual de silte e os valores da razão C/N, de B, Ba, Pb, Cu, Cd e Mn são os descritores ambientais significativos na distribuição da biocenose. A partir dos resultados obtidos conclui-se 1) a área controle utilizada pela Petrobras não é muito adequada, pois há indícios de impacto antropogênico, 2) a tanatocenose é substancialmente diferente da biocenose, portanto deve-se utilizar preferencialmente dados baseados em organismos vivos, 3) o valor de 20 cm3 de sedimento, estipulado pelo IBAMA, para a análise dos foraminíferos, é muito pequeno para se detectar indivíduos vivos em regiões impactadas. Portanto, para futuros estudos de biomonitoramento na região sugere-se escolha de ponto controle sem vestígio de impacto antropogênico, de preferência longe do rio Sergipe e que o volume de sedimentos para o estudo de foraminíferos vivos seja aumentado para no mínimo 50 cm³.
The objectives of this study were 1) to evaluate the environmental quality of sediments around the marine outfall of treated petrochemical effluents from Polo do Atalaia, Sergipe and 2) to provide technical and scientific information in order to improve biomonitoring studies carried out in that region. For these purposes the following analysis were performed: grain size, geochemical (nutrients, metals, metalloids, hydrocarbons), and meiofauna (foraminifera biocoenoses and thanatocoenoses) on replicates of 19 sediment samples collected from around the outfall (experimental area) and from a control area located 5 km north of the outfall. These 57 samples and their respective abiotic data were provided by Petrobras. Most of the studied area is composed of sandy silt sediments. However, in the experimental area there is a predominance of mud, rich in organic carbon and total phosphorus. In the control area, the percentages of very fine sand are higher and high values of total nitrogen occur. The concentrations of Pb, Cr, Ni, Zn on the two studied areas are below level 1 of the Conselho Nacional do Meio Ambiente (CONAMA) (National Council for the Environment) and ISQG (Interim Sediment Quality Guidelines), meaning that the sediments are not contaminated by these metallic elements. However, the values of As are between limits 1 and 2 of CONAMA and TEL and PEL (probable effect level) in all stations, indicating that the biota might be affected by this element. One of the samples (from the experimental area) presents values of Cd, Cr and Hg between the limits of ISQG and PEL and another sample (control area) has concentrations of Cr above level 2 and PEL. Concentrations of total petroleum hydrocarbons (TPH), resolved petroleum hydrocarbons (RPH) and unresolved complex mixtures (UCMs) are higher in the experimental area and in two samples from the control area. Thanatocoenoses composition is very different from biocoenoses composition, reinforcing the fact that mainly living organisms should be used in environmental impact analysis studies. The sediment used for the analysis of foraminifera oscillated between 20 and 110 cm³ to find around 100 living individuals. Percentage of silt and C/N ratio, B, Ba, Pb, Cu, Cd and Mn values are significant environmental descriptors in the distribution of biocoenoses. From the results obtained it is concluded: 1) The control area used by Petrobrás is not very adequate since there are evidences of anthropogenic impact, 2) Thanatocoenoses is substantially different from biocoenoses, and consequently, data based on living organisms should preferably be used, 3) the 20 cm³ sediment amount, stipulated by IBAMA for the analysis of foraminifera, is too small to detect live individuals in impacted regions. Therefore, it is suggested that a control point without trace of anthropogenic impact should be chosen for future biomonitoring studies in the region, preferably away from the Sergipe river. It is also suggested that the sediment volume for the study of live foraminifera be increased to a minimum of 50 cm³

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49

Maslen, Ercin. "Evaluating the source, age, thermal history and palaeoenvironments of deposition of Australian and Western Canadian petroleum systems: compound specific stable isotopes coupled with inorganic trace elements." Thesis, Curtin University, 2010. http://hdl.handle.net/20.500.11937/1098.

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Petroleum geochemistry is an important scientific discipline used in the exploration and production of hydrocarbons. Petroleum geochemistry involves the applications of organic geochemistry to the study of origin, formation, migration, accumulation and alteration of hydrocarbons.Key concepts and applications of petroleum geochemistry include understanding the petroleum systems, biomarkers and stable isotopes for oil‐oil and oil‐source rock correlations and controls on secondary processes (e.g. biodegradation, water‐washing and migration‐contamination) altering the composition and usually the quality of petroleum.In this research, important concepts and novel techniques of petroleum geochemistry have been utilized for characterizing the source rocks, evaluating the thermal history of the source rocks, understanding the age (where possible), establishing the depositional environment and lithology of the source. More specifically, various innovative organic (biomarker and stable isotopes) and inorganic (trace elements) geochemical approaches were undertaken to establish source, age, thermal history and sedimentary depositional environments of petroleum systems in Western Australia and Western Canada petroleum basins.The aim of the study presented in Chapter 2 was to understand the enigmatic occurrence of crocetane (an irregular C20 isoprenoid), that is usuallyfound in sediments associated with gas hydrate settings and used as a molecularindicator for the anaerobic oxidation of methane (AOM), in Devonian sediments and crude oils containing molecular indicators of photic zone euxinia (PZE).This study comprised a detailed molecular and isotopic study of crocetane and Green Sulfur Bacteria (GSB)‐derived carotenoids in Devonian sediments of the Western Canada Sedimentary Basin (WCSB) covering a range of thermal maturities. In addition, a series of oils generated from Devonian source rocks of the basin were analysed for crocetane. Crocetane was found in ten sediments from the WCSB and in seven Devonian WCSB crude oils. Its abundance was found to increase with thermal maturity, whereas the components generated from C40 derived carotenoids of GSB decreased steadily. The preferred proposed natural product precursor for crocetane is thus GSB‐derived carotenoids. This was corroborated by their similar structural features and the δ13C value of combined crocetane and phytane in these samples. Based on the work presented in Chapter 2, it was concluded that crocetane can provide evidence for PZE conditions in highly mature sediments and crude oils of Devonian age.Application of δD values of individual hydrocarbons (isoprenoids and nalkanes) has a great potential to estimate the thermal maturity of sedimentary organic matter. In Chapter 3, to elucidate the effect of thermal history on the δD values of petroleum hydrocarbons, (i) a comprehensive literature review, focussing on variations in δD values of sediment extracts, crude oils (including bulk organic matter and hydrocarbon fractions as well as individual nalkanes and isoprenoids) and kerogen was carried out and (ii) the application of δD values of hydrocarbons as a maturity parameter with new data from Devonian source‐rocks in the WCSB was tested.Previous work has been used to demonstrate systematic variation in D/H of individual compounds in sediments as a function of thermal maturity and our research in Chapter 3 extended the application of D/H of biomarkers to Devonian samples from the Duvernay Formation of the Western Canada Sedimentary Basin (WCSB) which is much older deposits (i.e. Devonian) than previously studied.Based on the work presented in Chapter 3, the n‐alkanes, pristane and phytane from relatively immature sediments have δD values that retain the isotopic signature of their natural product precursors, i.e. biosynthesised lipid components made up of acetyl and isoprene sub‐units, respectively. With increasing maturity, pristane and phytane become more enriched in deuterium (D), while the n‐alkanes generally remain at a constant isotopic composition until an overmature level is reached, at which point there occurs a significant enrichment of D in n‐alkanes. The enrichment of D in pristane and phytane with increasing maturity correlated strongly with changes in traditional maturity parameters including vitrinite reflectance, Tmax, and molecular parameters, providing evidence that D‐enrichment is associated with thermal maturation.The maturity indicator based on compound‐specific δD values has proved useful in cases where traditional biomarker maturity parameters are ineffective, for example at high maturity levels (i.e. % Ro >1.0) or where their associated reactants and products either equilibrate, or are thermally degraded. In addition, such a maturity measurement is applicable to Devonian sediments, where vitrinite reflectance measurements cannot be made because the higher‐plant precursors of vitrinite have not yet evolved.In Chapter 4, an integrated study including organic (stable carbon isotopes of individual hydrocarbons) and inorganic (trace elements) geochemical data, along with statistical analysis (linear discriminant analysis) was carried out for the first time to assess the source and age characteristics of crude oils from Western Australian and Western Canada petroleum basins.A novel rapid, reliable and accurate method of determination of major and trace element contents of crude oils was developed based on Laser Ablation Inductively Coupled Plasma‐Mass Spectrometry (LA‐ICP‐MS). This method has been applied for the first time to a series of petroleum samples for analysis of Fe, Mg, Al, Zn, Cu, Cr, Ni, Co, V, Tm, Mn, Ge, Dy, Si, Pb, B, Sn, Ti, Hg, As, Mo and Se at trace levels, with little or no sample pre‐treatment. δ13C values of individual hydrocarbons were carried out in a systematic manner to compliment the trace element data.The scatter plot of two discriminant functions from the analysis of trace elements (V, Pb, B, Mg, Sn, Ti, Mo and Hg) in crude oils samples confirms the capability for separating samples into their petroleum basins. 91.3% correct classification of the samples analysed was achieved. Analysis using two discriminant functions of combined trace elements (Al, Cr, Ti, Fe, Cu, Si, Tm, Mn, Ge, and Dy) and δ13C of Naphthalene (N), Biphenyl (Bp) resulted in 100% of samples being correctly classified according to their source rock age.In summary, based on the work presented in Chapter 4, the application of linear discriminant analysis and the stable carbon isotope values and trace element concentrations has allowed the classification of crude oils to their geographical (or basinal) sources and age. The use of complimentary inorganic trace element and organic stable isotope techniques for crude oil samples has been demonstrated as a new highly discriminant tool for petroleum exploration.The research presented in Chapter 5 is aimed at establishing the factors controlling the stable carbon isotopic compositions of individual aromatic hydrocarbons analysed by compound specific isotope analysis (CSIA) in crude oils from Western Australian petroleum basins of varying age and facies type but of similar thermal maturity. An evaluation of the data on δ13C of individual aromatic hydrocarbons, like alkylbenzenes, alkylnaphthalenes, alkylphenanthrenes and methylated biphenyls has been carried out to confirm the source and age of these oils and to understand why the Sofer plot is ineffective in establishing source of Western Australian petroleum systems. Previous isotopic work on the oils was mainly based on their bulk δ13C values of saturate and aromatic hydrocarbons. Western Australian oils seemed to follow an erroneous trend regarding their depositional environments (marine vs terrigenous) when they were assessed using only bulk isotopic values.The interpretation of the data presented in Chapter 5 showed that the oils where the δ13C of 1,6‐DMN (dimethylnaphthalene) and 1,2,5‐TMN (trimethylnaphthalene) isomers is most negative are probably derived from a marine source, whereas oils containing 1,6‐DMN and 1,2,5‐TMN with a less negative value are representative of a terrigenous source. The δ13C values falling in between probably have mixed source(s). Less negative δ13C values of 1‐MP and 1,9‐DMP isomers probably reflects the varying inputs of terrigenous organic matter to the source‐rocks of the oils. In addition, plots of P (phenanthrene) /DBT (dibenzothiophene) and Pr (pristane)/Ph (phytane) versus δ13C of DMP (dimethylphenanthrene), 1,6‐DMN, 1,2,5‐TMN, 1‐MP (methylphenanthrene) and 1,9‐MP are constructed to establish the end‐members of terrigenous and marine sourced oils. The ratio of P/DBT and/or the ratio of Pr/Ph and δ13C of aromatic isomers (such as 1,6DMN, 1,2,5‐TMN, 1‐MP and 1,9‐MP) when coupled together, provide a novel and convenient way of establishing crude oil source rock origin and sometimes even lithologies.In summary, oils from terrigenous depositional environments based on their bulk δ13C values were classified as marine based on their δ13C values of individual aromatic compounds. The compound specific isotope data of the aromatic hydrocarbons obtained for the oils may provide opposite conclusions regarding the source of the oils compared to bulk data using the Sofer plot. Thus, great care must be taken when interpreting isotope values of hydrocarbons, particularly those that are only based on bulk parameters.Ultimately, this project has demonstrated that analyses of molecular fossils (biomarkers) and their stable isotopic compositions (δ13C and δD) complemented with trace element data provides an excellent novel tool for better understanding the basic concepts in petroleum basins and for solving a wide range of problems during petroleum exploration.

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Krizanich, Gary W. "An investigation of lead and other metal contaminants in the sediments of Clearwater Lake, Missouri." Diss., Rolla, Mo. : University of Missouri-Rolla, 2007. http://scholarsmine.mst.edu/thesis/pdf/krizanich_dis_09007dcc80601ec2.pdf.

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Thesis (Ph. D.)--University of Missouri--Rolla, 2007.
Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed July 31, 2008) Includes bibliographical references (p. 185-197).

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