The exposed metamorphic core complexes in the Cyclades continental back-arc of southeast Greece host a range of base and precious metal deposits. Shallow crustal mineral deposits that formed since the late Miocene to active seafloor hydrothermal systems occur in the footwall and hanging wall of the major detachment systems and within all tectono-stratigraphic units. The carbonate-replacement, vein-type, intermediate-sulfidation epithermal, and skarn deposits tapped different sources of metals and fluids along the major low-angle detachment systems and steep normal faults. This study links the regional metallogenic diversity to fluid and crustal sources, within a framework of the evolving geodynamic context and complex basement structure. Over 30 mineral occurrences, from Lavrion of Attica on the Greek mainland across the Cycladic archipelago to Milos and Santorini on the active South Aegean volcanic arc, were investigated, encompassing ~40,000 km2 of the arc- to backarc system. Petrographic observations are combined with mineralogical, geochemical, and isotopic analyses (Pb, Sr, δ34S and δ18O) of galena (PbS) and ore-associated hydrothermal barite (BaSO4). New galena Pb isotope data complemented by Pb isotope data of galena from the literature exhibit a range of isotopic ratios, with a resolvable geologic pattern. Galena from deposits in the north-central Cyclades has low 206Pb/204Pb ≤18.84, while galena from the west Cyclades has higher 206Pb/204Pb ≥18.84. This distinct regional pattern is further supported by the Sr isotope signature of hydrothermal barite, with 87Sr/86Sr ≥0.711 in the north-central Cyclades and 87Sr/86Sr  ≤0.711 in the west Cyclades. When considered together with compiled Pb and Sr isotope data of potential source rocks, large-scale regional patterns in the isotopic signatures are recognized, suggesting two distinct sources of lead and strontium in the underlying basement of the core complexes. These two sources (Lower Cycladic Blueschist Nappe and Upper Cycladic Blueschist Nappe including the Cycladic Basement) correspond to known tectono-stratigraphic units of different provenance and age and help to correlate the basement over considerable distances, even where exposures are limited. Sulfur and oxygen isotope data of barite indicate variable contributions of sulfur from seawater and magmatic fluids among the range of deposit types. This indicates that different fluid generations evolved and tapped the basement, likely along the major detachment faults. The δ34S values of barite indicate that mineral deposits in the Cyclades can be clearly distinguished. Compiled whole-rock isotopic and geochemical data of the basement lithologies exhibit a broad dispersion. Miocene to recent mineralization in the Cyclades caused homogenization of the crustal sources and indicate regional lithological differences in the architecture of the exposed metamorphic core complexes. This thesis demonstrates that regional studies of the geochemical and isotopic composition of mineral deposits can provide additional constraints for the paleogeographic reconstruction of juxtaposed tectono-stratigraphic units across the Cyclades and other complex continental back-arc systems.

No description available.

The polymetallic carbonate-replacement prospect at Piavitsa is part of the ore-forming system of the Stratoni Fault Zone within the Kassandra mining district in northeast Greece. This district constitutes the southern segment of the Serbo-Macedonian belt, a promising region for the exploration of precious and critical metals in Greece. This master thesis is framed within the X-MINE project under the Horizon 2020 program. Three main objectives are defined: (1) to characterize the mineralization at Piavitsa utilizing reflected light microscopy, microprobe, and laser-ablation inductively coupled mass spectrometry (LA-ICP-MS), and (2) to evaluate the contributions of the scanning GeoCore X10 (XRF-XCT) technology to the understanding of the ore, and (3) to assess potential environmental impacts. At Piavitsa, an early base-metal assemblage, composed of brecciated sphalerite and As-rich pyrite, is infilled and overprinted by an assemblage of As-poor to moderately-rich pyrite, alabandite, and Mnrich sphalerite. The latter two are corroded and replaced by Mn-rich carbonate. Fractures and interstices are infilled by a late assemblage of Ca-Mn-Mg carbonate, galena, As-poor pyrite, tetrahedrite-tennantite, and in the periphery of the orebody, seligmannite-bournonite and kesterite.  Based on absolute elemental concentrations obtained by in situ LA-ICP-MS, the mineral hosts (primary; secondary) are defined as: pyrite (Fe, Co, Ni, and Au; As), sphalerite (Zn, Ga, Ge, Cd, Sn; Mn), galena and bournonite (Pb, Se, Te, Tl, and Bi; Ag, Sb), alabandite (Mn; Cd and Sb), and tetrahedrite (Cu, As, Ag, and Sb). In cocrystallized assemblages, some differences are observed. In pyritetetrahedrite asemblages, tetrahedrite mainly hosts As and Au, instead of pyrite, whereas in sphaleritealabandite assemblages, alabandite is the host of Mn, As, Ag and Sb and sphalerite, of Cd and Sn. Three concentrates are produced from the current mining operations of Hellas Gold in the Stratoni area, e.g, Mavres Petres Zn-Pb mine. From LA-ICP-MS, it is inferred that a sphalerite concentrate from the Piavitsa ore would contain Ga (peripheral ore: 150 ppm; main ore: 10-40 ppm), Sn (peripheral ore: 800-1500 ppm; main ore: 25-230 ppm), and Cd (1600-4000 ppm). The galena concentrate would contain concentrations of Ag (1300-1700 ppm), Se (50 ppm), Sb (1200-1600 ppm), and Te (85-210 ppm). The pyrite concentrate would contain Au (0.5-24.5 ppm) but would be devoid of other economical trace elements. The values given here consider 100% purity, instead of 80-90% reported in previous studies. The GeoCore X10 technology provides a good indication of measurable elements. (>0.01 wt.%), including Mn, Fe, Cu, Zn, and Pb; As, Sb and Sn. Moreover, it helps to quickly identify the main ore and gangue minerals and their distribution in the deposit. The distinction between the ore and gangue minerals can be easily achieved based on the difference in their X-ray attenuation. It is worth highlighting that mineralogical info obtained by other analytical methods is still essential to validate the outputs of the instrument and to improve the interpretations drawn from them. Regarding the environmental impacts of mining the ore, the potential for acid generation and pollutant mobilization are low due to the carbonate-rich matrix. The mining poses low radioactivity risks due to the low concentration of radionuclides. Establishing a pollutants baseline and monitoring the surrounding water bodies and soils is highly recommended to reduce overlooked environmental impacts.

The purpose of this study was to assess the metal content present in pine needles collected from an old shooting range known for elevated lead levels in the soil by different analytical methods. The focus on conifers originated from their evergreen nature year-round, and their ability to absorb potentially harmful elements. Research on needles as biomonitors for environmental contamination, particularly in areas affected by heavy metal pollution, has gained significant global attention. Four trees, two Norway spruces (Picea abies), and two Scots pines (Pinus sylvestris) were identified within the designated area. Samples of conifer needles were collected in plastic bags. The needles underwent washing, drying, and grinding into powder for subsequent digestion method and quantitative determination of metal content using ICP-MS and MPAES. The study focused on elements commonly found in various types of ammunition, specifically manganese, iron, nickel, copper, zinc, molybdenum, antimony, and lead. Results obtained from both analytical methods, which was only manganese, showed statistically significant differences. During the analysis, only manganese could be quantified using MPAES, as the other analytes were below the detection limit. For ICP-MS, the LOD values were much lower, making this method more suitable, as all analytes were above LOD and could be quantified. The recovery values for the CRM were good for all elements when ICP-MS was utilized. However, the calculated recovery value for manganese decreased based on the results obtained from MPAES compared to the calculated recovery value for manganese based on the results obtained from ICP-MS. Interestingly, the analysis of conifer needles revealed no noticeable contamination from the shooting range. Instead, it highlighted variances among different pine needle species. The metal content in the pine needles remained within acceptable limits according to external literature sources.

京都大学 / 新制・課程博士 / 博士(工学) / 甲第25265号 / 工博第5224号 / 新制||工||1996(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 米田 稔, 教授 松井 康人, 講師 山本 浩平, 教授 橋本 訓 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

Tenint en compte, les característiques i la presència d’urani i tori al medi ambient, així com la evolució de les directives que estipulen els nivells màxims de materials radioactius al medi ambient, en aquesta tesis es presenten dues revisions exhaustives i quatre mètodes analítics per a la determinació total e isotòpica de tori i urani, com alternatives a les separacions radioquímiques clàssiques, que es caracteritzen per ser laborioses i de llarga duració. Aquestes metodologies varen ser automatitzades mitjançant l’ús de tècniques d’anàlisis en flux multiconmutades, les quals proporcionen un important estalvi de reactius, amb la conseqüent reducció de cost per anàlisis i de generació de residus permetent una major freqüència d’anàlisis, i una mínima manipulació de les mostres. La espectrofotometria de llarg pas òptic i la espectrometria de masses de plasma acoblat inductivament (ICP-MS) varen ser les tècniques de detecció emprades en els mètodes desenvolupats com alternatives a detectors radiomètrics. / Taking into account the occurrence, the characteristics of uranium and thorium in the environment as well as the evolution of the directives which stipulate the limit values of radioactive materials in water samples, in this thesis two comprehensive reviews and four automated analytical systems for total and isotopic thorium and uranium determination are presented as alternatives to classical radiochemical separations which are laborious and time consuming. These methodologies have been automated exploiting multicommutated flow techniques, which provide minimal sample handling, low reagent consumption and waste generation and a high frequency of analysis. Long path length spectrophotometry and ICP-MS have been implemented in the developed methods as detection techniques instead of radiometric detectors in order to obtain fully automated, low cost and fast thorium and uranium analyzers. All the developed methods proposed in this thesis have been satisfactorily applied to environmental samples and have been validated with reference materials

Bei der Schwefelquantifizierung in Kupfer und anderen reinen Metallen zeigte sich in der Vergangenheit eine mangelnde SI-Rückführung und zusätzlich inkonsistente Ergebnisse, wenn verschiedene Methoden verglichen wurden. Um diesen Mangel zu beheben ist ein Referenzverfahren erforderlich, welches SI-rückführbare Werte mit einem zuverlässigen Unsicherheitsbudget ermöglicht. In dieser Studie wurde ein entsprechendes Referenzverfahren zur Quantifizierung von Gesamtschwefel in Kupfer basierend auf der induktiv gekoppelten Plasma-Massenspektrometrie und der Isotopenverdünnungsanalyse (ICP-IDMS) entwickelt. Um diese Probleme zu lösen wurde mit Hilfe der Ionenaustauschchromatographie ein Schwefel-Matrix-Trennverfahren entwickelt. Dieses Trennverfahren wurde mit ICP-IDMS kombiniert, um Schwierigkeiten mit der Kalibrierung zu lösen und fehlende metrologische Konzepte einzuführen. So wurden die in diesem Projekt erzielten IDMS-Messwerte für die Kalibrierung von GDMS und LA-ICP-MS verwendet, beides Verfahren die im industriellen Einsatz üblich sind. Dadurch konnten mit beiden Routineverfahren zuverlässige Ergebnisse erzeilt warden, die zudem auf SI rückführbar sind. Darüber hinaus wurde ein auf der LA-ICP-IDMS basierendes Verfahren entwickelt, um den Probenvorbereitungsschritt von ICP-IDMS mit Schwefel-Matrix-Trennung zu reduzieren. Die Vorteile dieser Methode sind ein geringerer Arbeits- und Zeitaufwand, die SI- Rückführung der Messergebnisse und eine für LA-ICP-MS vergleichsweise hohe Genauigkeit. Die Schlüsselrolle hierbei spielte der innovative Einsatz von Polyethylenfritten als Trägermaterial der aufgelösten Probe. Dadurch war die Quantifizierung von Schwefel in Kupferproben mittels LA-ICP-IDMS möglich. Die wesentlichen Parameter wie Absorptionseffizienz der Fritten und Matrixeffekt wurden untersucht. Das entwickelte Verfahren konnte mit Hilfe der ICP-IDMS vollständig validiert werden. / Sulphur quantification in copper and other pure metals in the past revealed a lack of SI-traceability and also showed inconsistent results, when different methods are compared. Therefore, a reference procedure is required to enable SI-traceable measurement results accompanied by a sound uncertainty budget. In this study, such a procedure was developed for the quantification of total sulphur in copper using inductively coupled plasma-isotope dilution mass spectrometry (ICP-IDMS). For solving these problems ion exchange chromatography was applied, and a sulphur-matrix separation procedure was developed. This procedure was combined with ICP-IDMS to solve difficulties with the calibration and to realize metrological concepts. An application of the IDMS procedure was realized by using the measurement results of specific copper samples values for calibrating glow discharge mass spectrometry (GDMS) and laser ablation ICP-MS (LA-ICP-MS). Both techniques are considered routine techniques. Thus, they could provide reliable results which are traceable to the SI. Additionally, a procedure based on LA-ICP-IDMS was developed to significantly reduce the sample preparation step of ICP-IDMS with sulphur-matrix separation. This procedure is less laborious and the measurement results are still SI traceable and offer a comparatively high accuracy for LA-ICP-MS. Key for this development was the innovative application of polyethylene frits as support material for the dissolved sample. Thus, the quantification of sulphur in copper samples by LA-ICP-IDMS could be realized. The essential parameters are investigated such as the absorption efficiency of the frit and matrix effects. The developed procedure was fully validated by means of the ICP-IDMS results.

Also aged bottles are safer to use than new bottles because their chemical leaching was found to be lower than that of new bottles. This study recommends the reassessment of the absence of international guidelines for acetaldehyde in water and foods. The study also recommends that the amount of acetaldehyde that can be added to soft drinks as flavouring agent should be below the specific migration limit (SML) for migration of acetaldehyde from PET bottle into bottle contents. This is essential since the SML was designed to ensure that exposure to acetaldehyde, as a result of intake of bottled water and soft drinks in PET bottles, is below the tolerable daily intake (TDI) for acetaldehyde. As antimony was reported to go beyond the safe limits in some Nigerian bottled water and soft drinks after 11 months of storage this study discourages the use of bottle contents stored for a very long time.

This thesis describes studies on the analysis of arsenic (As) in human biological samples, mainly urine but also hair and fingernails using inductively coupled plasma mass spectrometry (ICP-MS) and graphite furnace atomic absorption spectrometry (GF-AAS). The relationship between ethnicity and arsenic metabolism was investigated for the first time for a population in the United Kingdom. This investigation has been carried out through comparative analysis of arsenic in human urine, hair and fingernails in volunteers from three different ethnic groups (Whites, Asians and Somali Black-Africans) who are only exposed to background levels of arsenic. Results obtained with 63 volunteers showed ethnic differences in urinary arsenic excretion as well as differences in arsenic levels in fingernail samples. The averages of total arsenic levels for the Somali Black-Africans (urine 7.2 µg/g creatinine; fingernails 723 µg/kg) are significantly (P< 0.05) different from both the Asians (urine 20.6 µg/g creatinine; fingernails 153.9 µg/kg) and Whites (urine 24.5 µg/g creatinine; fingernails 177.0 µg/kg). The Somali group also shows a higher percentage (50%) of dimethylarsinate (DMA) and a lower percentage (48%) of arsenobetaine (AB), compared to Asians (16% DMA and 83% AB) and Whites (22% DMA and 77% AB). The effect of fasting on urinary arsenic species distribution was also investigated by monitoring urine samples from 29 Ramadan fasting volunteers, with each volunteer providing a sample at the beginning (RF1) and at the end (RF2) of an approximately 12 hours fast. The results obtained showed the frequency of MA detection for RF2 was 12 and 2-fold higher than for the non-fasting and RF1 groups, respectively. This suggests fasting may alter the pattern of arsenic metabolism and excretion. However, there was no significant difference (P> 0.05) in the average of total level of arsenic for RF1 (18.3 µg/g creatinine) and RF2 (17.7 µg/g creatinine). A relationship between excretion of arsenic and selenium in individuals exposed to background levels of arsenic and selenium was investigated through analysis of urine samples from 93 volunteers from Leicester, UK. A positive correlation between arsenic and selenium was found and the As:Se ratio was 0.7 ± 0.4. The intra-individual variation of As:Se ratio does not alter significantly over time, as determined by monitoring urine samples from a volunteer over a period of one year. Furthermore, within a single day, with urine samples collected at the beginning and after a 12-hour fast, the As:Se ratio was found to be similar (0.7 ± 0.5). These findings suggest a close relationship between these two metalloids, the biological significance of which needs to be explored in the future.

The application of ICP-MS to the fields of proteomics and genomics has arisen in part due to its ability to detect and quantify trace levels of S and P, which are major constituents in proteins and nucleic acids respectively. The development of collision/reaction cell technology and high resolution instruments has enabled these biologically important elements to be measured and quantified at the pg - ng ml-1 level. Despite these advances, the detection limits of P and S are still inferior compared to other elements. Oligonucleotides containing biotin functionality were labelled with Au nano-particles attached to a streptavidin protein to achieve site specific labelling, with 100% labelling efficiency. Each nano-particle contained ~86 Au atoms, resulting in an 882 fold signal enhancement for 24 base length oligonucleotides. However, this enhancement factor was only observed when one oligonucleotide bound to one nano-particle in a 1:1 ratio. Much lower Au labelling efficiencies and signal enhancements were observed when thiolated oligonucleotides were labelled with maleimide functionalised gold nano-particles. This was attributed to the extensive and difficult sample preparation steps that were required prior to labelling. The detection and quantification of adducts formed between DNA and the Pt anti-cancer drugs cisplatin and oxaliplatin were also investigated with ICP-MS. Acid digestion of the carbon based DNA matrix enabled Pt adducts to be quantified at low dose rates of 1 Pt atom per 1 500 000 nucleotides in ~12 μg DNA. Such sensitive mass spectrometric determinations could be employed in clinical tests to detect and quantify low level adducts formed in patients in-vivo. To complement ICP-MS analysis, electrospray ionisation linear ion trap mass spectrometry was employed to study the interaction of oxaliplatin with the four DNA nucleobases. Multiple stage mass spectrometry enabled detailed Pt-nucleobase adduct fragmentation pathways to be established. The method of DNA detection using P in conjunction with the collision cell, or cool plasma to form PO+ was also demonstrated and the limitations of the method, namely, polyatomic interferences and severe matrix effects were highlighted.