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Metaller og naturlig organisk materiale i arktiske elver på Svalbard / Metals and Natural Organic Material in Arctic Rivers on SvalbardNordum, Mats January 2012 (has links)
I denne oppgaven har det blitt utført kartlegging av innhold av elementer og oppløst organisk karbon (DOC) i elvevann og skum i Bayelva og Londonelva, to arktiske elver med utløp i Kongsfjorden på Svalbard. Andre viktige parametere som pH, redokspotensiale, ledningsevne og temperatur har også blitt målt. Filtrerte (0,45 µm) og ufiltrerte vannprøver har blitt prøvetatt manuelt, samt med DGT (diffusjonsgradienter i tynne filmer), og analysert med HR-ICP-MS. Det ble funnet generelt lave konsentrasjoner av oppløste sporelementer i elvevannet i både Bayelva og Londonelva, og konsentrasjonene var under grenseverdier fra norske myndigheter for metaller i ferskvann. Det er forskjeller på elementkonsentrasjoner innad i elvene, og innholdet er høyere for de aller fleste elementer i Bayelva sammenliknet med Londonelva. Forskjellene i konsentrasjoner i de to elvene kan forklares av ulik geologi og hydrologi i de to nedbørsfeltene. DGT-ene ser ut til å ha blitt kontaminert. Innhold av oppløst organisk materiale er lavt, men detekterbart i begge elver. SUVA254 indikerer at det organiske materialet har hovedsaklig aromatisk karakter. Estimat for årlig tilførsel av oppløste metaller til Kongsfjorden har blitt regnet ut. Skumprøver inneholdt betydelige konsentrasjoner av DOC og elementer, og en oppkonsentrering av metaller i forhold til elvevannet er tydelig i både Bayelva og Londonelva. Høyest oppkonsentrering ble funnet for Pb, Zn og Cu. Signifikante positive korrelasjoner ble funnet mellom Fe og Mn og Fe og Al i vannprøver fra Bayelva, samt mellom Fe og Pb i to av prøvepunktene. I Londonelva ble det funnet signifikant positiv korrelasjon mellom Fe og Pb, i tillegg til en negativ relasjon mellom Al og As. Korrelasjoner mellom metaller er en indikasjon på at disse metallene har felles kilde og/eller transportmekanismer. Tydelige signifikante positive korrelasjoner ble funnet for Mn, Cu og Pb mot DOC i vannprøver fra Londonelva, og for Mn, As, U og hardhet mot DOC i skumprøver fra Bayelva. Det ble funnet dagsvariasjoner i elementkonsentrasjoner og ulike måleparametere i de to elvene, men variasjonene er mindre tydelig i Londonelva. Prøveantallet var lavt, og endring i vannføring ser ut til å forklare vari
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Distribution and Variation of the Trace Metal Iron in the Base of the Pelagic Marine Food Web: A Mesocosm Approach : Trace Metal in marine biologySanchez, Nicolas January 2012 (has links)
This study was part of the WAFOW project “Can waste emission from fish farms change the structure of marine food webs?” whose objective was to perform mesocosms experiment to simulate the ammonium enriched environment, caused by salmon aquaculture. In order to assess how changes in the stoichiometry of major elements (nitrogen) in the sea affect the distribution of bioactive trace metals, and its effects on the base of the pelagic food web, the distribution and variation in time of the trace metal iron in the water and within the plankton community was studied along a 22 day experiment. It involved 2 types of water (surface and marine systems) each one, with 1 control and 4 NH4+ concentrations. Additional samples collected in a river transect and in depth provided the general Fe distribution in the environment. The iron concentration in the water was determine for three fractions as: Chelex labile (Total: TFeCh and dissolved: DFeCH), DGT labile (FeDGT) and direct (Total: TFe and dissolved: DFe), whereas the particulate concentration iron in the plankton community was determined both per fraction (PFeSF) and total content (PFe>0.2). Total average per treatments showed higher concentrations for both TfeCh and DFeCh in the marine systems compare to the surface. TFeCh showed general increasing trend in time and with increase NH4+ concentration, with a sharp decrease towards the end of the experiment in both systems. DFeCh pattern was inverse to TFeCh, with general decrease over time but lower in magnitude. FeDGT showed an average lower concentration compare to DFeCh with no define trend over time. Final FeDGT concentrations were significantly lower in treatments with artificial NH4+ addition. PFe>0.2 showed an increasing trend in time and with increased NH4+ in both systems. However when normalized to Chlorophyll-a (Chl-a) or particulate organic carbon (POC) the trend inverted, showing that at higher NH4+ influx the iron per Chl-a or POC decreases. PFeSF major changes occurred in the marine system where a estimation of the ratio between the 20-140 µm and the 2-20 µm fractions, indicative of the dominant phytoplankton size class, was significantly higher in 2 of the 3 treatments with artificial NH4+ addition. This point that the microphytoplankton increased significantly with higher NH4+. The variation over time of the concentration of Fe in the water as in the plankton community, indicate that the concentration of NH4+ can have positive or negative relation depending on the iron form. Whether via increasing the PFeCh, or by reducing the uptake by phytoplankton, a modified C:N:P can affect the cycling of iron, which in turn can have negative or positive feedbacks over the major biogeochemical cycles.
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Kartlegging og overvåking av tungmetaller i oljesandområder / Monitoring of Heavy Metals in Oil Sand AreasBechmann, Pernille January 2011 (has links)
I denne oppgaven har det blitt utført kartlegging av bakgrunnskonsentrasjoner av utvalgte grunnstoffer og andre viktige parametere (pH, DOC og TDN) i overflatevann rundt Statoils oljesandfelt Leismer i Alberta, Canada. Vann har blitt prøvetatt manuelt for oppløst, syreløselig og total konsentrasjon, og med den passive prøvetakeren DGT (diffusjonsgradient i tynne filmer) for DGT-labil konsentrasjon. Prøvene har blitt analysert med ICP-MS. Voltammetri ble benyttet for analyse av metaller i felt for å se på døgnvariasjoner.Hensikten med kartleggingen er å vite hvilke nivåer av elementene som er naturlig i området for å kunne oppdage eventuelle effekter av Statoils drift i fremtiden. Dataene samlet inn i dette prosjektet vil ha liten eller ingen nytte hvis det ikke følges opp med nye undersøkelser i fremtiden.Resultatene viser at det generelt er lave konsentrasjoner av grunnstoffene som det finnes grenseverdier for konsentrasjoner av i vann. Det viser at vannkvaliteten er god og gjør det ekstra viktig at Statoil ikke forårsaker utslipp, siden selv små utslipp kan øke konsentrasjonene betydelig. I tillegg har det blitt sett på utvikling av en voltammetrisk metode for on-line overvåking av arsenkonsentrasjon. Formålet med utvikling av metoden var å kunne overvåke konsentrasjonen av As i grunnvannet som benyttes til drikkevann ved Leismer Lodge, fordi konsentrasjonen er forholdsvis høy. Arbeid med utviklingen av den voltammetriske metoden demonstrerte hvor kompleks arsens kjemi er, og det var ikke mulig å få til en reproduserbar og egnet metode i løpet av prosjektet. Resultatene kan forhåpentligvis være til nytte ved fremtidig arbeid med voltammetriske metoder for arsen.
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Investigations on the Applicability of Membrane Introduction as a Sampling Technique for Oil in Air and Water with Flame Ionization Detector (FID) and Mass Spectrometry (MS) DetectionTrefjord, Terese January 2012 (has links)
During a membrane introduction (MI) analysis the analytes are separated from the bulk matrix (e.g. air or water) by a semi-permeable membrane and transported to the detector by a carrier gas (usually helium). The most commonly used detector for MI-analyses is the mass spectrometer, resulting in membrane introduction mass spectrometry (MIMS). The main advantages of MIMS are short response times, high sensitivity, simplicity and elimination of sample preparation and pre-separation. Membrane introduction analyses are suitable for detection of volatile organic compounds (VOCs) and semi volatile organic compounds (SVOCs). In this project the applicability of MIMS and membrane introduction flame ionization detector (MIFID) for oil analyses were tested. Investigations of 12 different oil samples from light crude oils to heavy oils were performed by MIFID and MIMS for both water and air (only two oil samples were analyzed by water MIMS). For the oil in air analyses good response were achieved, and information about response times and half-times could be obtained within a reasonable period of time. The water analyses however showed some limitations. Even after long analysis times (up to 1200 minutes) useful information on response time were rarely obtained, and no half-times for depletion could be measured. Pre-equilibration of the oil samples seems to be necessary to enable reasonably fast MI analyses of water samples (approximately) equilibrated with the oil, allowing an estimation of oil concentrations in water. For the MIMS analyses spectral information are obtained, providing an indication of the content of the oil samples, as well as information about how the abundance of different ions change throughout the analyses due to weathering.Best results were obtained by the lighter oil samples, due to higher amounts of compounds favorable for MI-detection. Analysis times obtained were slightly shorter for MIFID analyses, as compared to MIMS analyses.
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Environmental toxicity of complex chemical mixturesGillespie, Annika Margaret 15 May 2009 (has links)
Complex chemical mixtures may be released into the environment from a variety
of sources including hazardous waste sites. Components of chemical mixtures and their
metabolites may be genotoxic leading to cancer and heritable gene mutations. Chemical
analysis alone does not always provide the most accurate information from which to
estimate the risk of adverse effects associated with exposure to mixtures. Current
methods to estimate the human health risk for complex mixtures assume additive effects
of the components. Although it is assumed that this approach is protective of human and
ecological health, it is also recognized that chemical mixtures may induce a variety of
interactions including potentiation, synergism, and antagonism. A combined testing
protocol, using chemical analysis coupled with a battery of in vitro, in vivo, and in situ
bioassays, provides the most accurate information from which to estimate risk. Such a
combined testing protocol provides information to describe the major organic and
inorganic constituents, as well as the pharmacokinetics and potential interactions of
chemical mixtures. This research was conducted to investigate the potential genotoxic
effects of complex chemical mixtures of polycyclic aromatic hydrocarbons (PAHs) and
polychlorinated aromatics (PCA) using microbial bioassays (Salmonella/microsome
assay and the E. coli prophage induction assay), the 32P-postlabeling assay in mice, and
in situ measurements of genotoxicity using flow cytometry. Samples of environmental
media and wildlife tissues were collected from four National Priority List Superfund
sites within the United States. In general, chemical analysis was not always predictive
of mixture toxicity. Although biodegradation reduced the concentration of total and
carcinogenic PAHs in soils and groundwater, the genotoxicity of extracts from environmental media did not display a corresponding reduction. Mixtures of
polychlorinated biphenyls (PCBs) extracted from sediments were found to inhibit the
genotoxicity of PAH mixtures when administered dermally to rodents. This inhibition
exhibited a dose-response relationship, with the adduct frequency reduced at increasing
doses of sediment extract. Finally, PAH concentrations in environmental media and
tissues were found to correlate with DNA damage in wildlife receptors. An integrated
approach, combining in vitro and in vivo methods to characterize genotoxicity provides
more accurate information from which to estimate uptake and risk associated with
exposure to complex mixtures and should be considered in both the human and
ecological risk assessment process.
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Enzymatic response of Callinectes sapidus and Geukensia demissa as biomarkers for pesticide exposure /Caveny, Heather R. January 2003 (has links) (PDF)
Thesis (M.S.)--University of North Carolina at Wilmington, 2003.
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Aquatic and terrestrial exposure of amphibians to estrogenic endocrine disrupting contaminantsMéndez, Sara I. Semlitsch, Raymond D. January 2009 (has links)
Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 15, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Raymond D. Semlitsch Vita. Includes bibliographical references.
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Identification of Sources for Illegal Oil Spills by Using GC-MS (Gas Chromatography and Mass-Spectrometry) Databases and Multivariate StatisticsKamalia, Uswatun Hasanah Isna January 2011 (has links)
Preparing a defensible oil spill fingerprinting is always challenging. Presently available well established method for this purpose is a univariate method by comparison of diagnostic ratio using repeatability limit as suggested by European Committee for Standardization (CEN)-method. The consistency result of this method, however, tends to depend on the skill of the analyst who performs the analysis. The shortcoming of CEN-method was then demonstrated by the application of the method to the "MS Server" and "MV Full City" oil spill cases. The author’s analysis result exposed some discrepancieswhen was compared with the one performed by SINTEF. Therefore, this thesis focuses on the effort of pursuing alternative or at least complimentary methods to ease the shortcoming of the CEN-method. The main investigation was then emphasized on the possibility of employing the multivariate analyses, i.e. principal component analysis (PCA), cluster analysis, and partial least square discriminant analysis (PLS-DA). The performance of those multivariate analyses were examined by applying to the case studies of "MS Server" and "MV Full City" oil spills. Later on, it was found that PCA failed to classify the samples properly according to the match or non-match with the reference samples. The power of the PCA was revealed when the method was combined with thecluster analysis. The PCA combined with the cluster analysis demonstrated to be faster and undoubtedly more objective (in term of the analyst skill and expertise) as compared to the CEN-method. PLS-DA also showed the same benefits. Moreover, the PLS-DA gives more similar result to the CEN-method applied by SINTEF (irrespective of the difference gaps of the analysts skill, i.e. the SINTEF researchers v.s. the author) as compared to the PCA combined with the cluster analysis. However, the main drawback of the PLS-DA is therequirement of quite large number of sample to obtain a good result. At last, we could see that there is possibility of applying several multivariate analyses, i.e PCA combined with the cluster analysis, and PLS-DA, for the alternatives or complementary of a well established univariate analysis of oil spill fingerprinting (CEN-method). In order to develop the alternative method(s) properly, further research is needed, especially the one which employs more controllable samples.
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A comparison of particulate matter (PM101) in industrially exposed and non exposed communities.January 2008 (has links)
BACKGROUND For many years, the Durban south community has raised concerns about ambient air pollution including particulate matter. The Durban South Industrial Basin (DSIB) may be high risk for exposure to significant levels ofPMI0 due to its geographic relationship with two major petroleum refineries, together with a pulp and paper manufacturing facility. While potential sources of elevated levels of PMlOin the south are industrial, the north is likely to be exposed to controlled burning of vacant fields and use ofbiomass fuels, particularly in informal settlements. Adverse health effects from particulate matter (PM) were well documented by extensive epidemiological observations by animal and human studies, following laboratory exposures. Studies across a variety of environmental settings have demonstrated a strong association between ambient air particulate matter (PMlO) and cardiopulmonary morbidity and mortality. Studies have reported that particulate matter is associated with adverse health effects resulting from inflammatory responses in the lower respiratory tract. Exposure to particulate matter may increase the risk of lung cancer. Some studies suggested that small temporal increases in ambient particulate matter are sufficient to cause health impacts. Other studies attributed strong seasonality to temperature inversions associated with temperature changes. Studies also illustrated the impact of temporal variation on PMl 0 levels across regions. OBJECTIVES The main objectives of this study were to determine and compare the levels of ambient PMIO in industry exposed and non-industry exposed communities, to determine temporal variation and to make recommendations. METHODS This study focused on determining the 24-hour ambient PMI0 levels in the Durban south community. The PMIO levels in Durban south (industry exposed) were compared with the PM10 levels in an area north of Durban (non-industry exposed). Relevant data obtained from the monitoring program of the South Durban Health Study (SDHS) was reviewed for the purposes of this study. The different techniques used to measure PMI0 are gravimetric sampling and tapered elemental oscillating microbalance (TEaM). Both methods were used to collect PMI0 data. The data comprised of quantitative and categorical variables. The dependent variable was the PM10 values and the independent variable was the sampling sites. Non-parametric tests were used to analyse the data. RESULTS PMI0 was recorded in all sites in north and south areas. The levels varied across all sites. Both the north and south areas recorded high PMI0 values at regular intervals. No particular trend was observed when the 24 hour PM10 concentration was compared against the standard. All sites recorded medians that were generally in the region of 40-S0,ug/m3. The site with the highest median (SIA,ug/m3 ) was Assegai. Briardale recorded the lowest median (34.9,ug/m3 ). Exceedances of the South African National Standard code 1929 maximum 24-hour concentrations of7S,ug/m3 were observed across all sites. Overall there were 163 (16.7 % of all samples) exceedances, and these ranged widely between the various sites, with no particular regional trend. Overall .June experienced the highest PMl 0 values. No differences in seasonal trends were observed in north and south. CONCLUSION On average the levels ofPMI0 do not exceed national or international standards. The findings did not reveal any statistical difference in exposure levels between the industry exposed and non-industry exposed areas. / Thesis (MMed.)-University of KwaZulu-Natal, Durban, 2008.
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Toxicant interactions with the biotic and abiotic environment of freshwater rotifers : implications for ecological risk assessmentPreston, Benjamin Lee 05 1900 (has links)
No description available.
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