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Analysis of Benzoisothiazolinone in process water from operations that handle large amounts of paint residues / Analys av bensisotiazolinon i avloppsvatten från verksamheter som hanterar stora mängder målarfärgsresterMagendran, Cagenna January 2022 (has links)
I denna studie undersöks isotiazolinoner i avloppsvatten eftersom det finns i alla kommersiella färger. För att avgöra om reningsverken är tillräcklig bra används gaskromatografi-masspektrometri (GC-MS) för att analysera förekomsten av BIT i processvatten som släpps ut i mjövattnet. Enligt ”Stockholms vatten och avfall” ska giftiga ämnen inte släppas ut i avloppsvattnet av någon med anknytning till det kommunala reningsverket. Ett företags processvatten undersöktes före och efter reningsprocessen, som baserades på flockning. En metod utvecklades för denna studie, för bestämning av BIT i vattenprover, som har visat positiva resultat för BIT-analys i färgvatten. BIT detekterades inte i företagets processvatten, som visade en koncentration på 0,1 ppm och lägre. Eftersom inga isotiazolinoner kunde detekteras före och efter rengöringsprocessen, kan resultaten inte bekräfta att rengöringsprocessen är effektiv för att eliminera isotiazolinoner. Eftersom BIT är den vanligaste isotiazolinon i färg kommer sannolikt inte ämnen som MI, MCI, OIT och DCOIT att överstiga 0,1 ppm i företagets processvatten. Det förväntas att BIT kommer att brytas ned biologiskt och inte skada vattenlevande organismer på grund av dess låga koncentration i processvattnet. Processvattnet från företaget skickades till eurofins för analys. Som framgår av Eurofins resultat har processvattnet från företaget en låg nivå av nitrifikation inhibering. ’’Stockholms vatten och avfall’’ reningsprocesser ska enkelt kunna ta bort BIT baserat på flera studier. Man kan dra slutsatsen från denna avhandling att BIT vid koncentrationer under 0,1 ppm inte skadar avloppsreningsverk. / In this study, isothiazolinone in wastewater is investigated since it is present in all commercial paints. To determine whether the treatment plants are sufficient,Gas chromatography-mass spectrometry (GC-MS) is used to analyze the occurrence of BIT in process water released into environmental water. According to ”Stockholm's water and waste”, toxic substances should not be released into the wastewater by anyone connected with the municipal waste water treatment plant. A company’s process water was investigated before and after the cleaning process, which was based on flocculation. A method was developed for this study, determining BIT in water samples, which has shown positive results for BIT analysis in paint water. BIT was not detected in the company's process water, which displayed a concentration of 0.1 ppm and below. Since no isothiazolinones could be detected before and after the cleaning process, the results can not confirm that the cleaning process is effective at eliminating isothiazolinones. Because BIT is the most common isothiazolone in paint MI, MCI, OIT, and DCOIT are unlikely to exceed 0.1 ppm in the company's process water. It is expected that BIT will biodegrade and not harm aquatic organisms because of its low concentration in the process water. The process water from the company was sent to eurofins for analysis. As shown in Eurofins' results, processed water from the industry has a low level of nitrification inhibition. ‘’Stockholm's water and waste’’ treatment processes should be able to easily remove BIT based on multiple studies. It can be concluded from this thesis that BIT at concentrations below 0.1 ppm does not harm WWTPs.
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Characterization of paint and varnish on a medieval Coptic-Byzantine icon: Novel usage of dammar resin?Abdel-Ghani, Mona H., Edwards, Howell G.M., Stern, Ben, Janaway, Robert C. January 2009 (has links)
No / A comprehensive study has been undertaken into a 13th century Coptic-Byzantine icon from the St. Mercurius Church, St. Mercurius monastery, Old Cairo, Egypt. The layered structure, pigment composition and varnish identification were revealed by means of optical and Raman microscopy and gas chromatography¿mass spectrometry (GC¿MS). The structure of the icon comprised six layers; wooden panel, canvas, white ground, two bole layers and a single paint layer. Azurite (2CuCO3·Cu(OH)2), cinnabar (mercuric (II) sulfide ¿-HgS), yellow ochre (Fe2O3·H2O), hydromagnesite Mg5(CO3)4(OH)2·4H2O and lamp black (carbon, C) are the pigments identified in the icon. The green paint area is of interest as it is applied neither with a green pigment nor with a mixture of a blue and yellow pigment. Instead, a yellow layer of dammar resin was applied on top of blue azurite to obtain the green colour. Pinaceae sp. resin mixed with drying oil was used as a protective varnish.
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Ancient lipids reveal continuity in culinary practices across the transition to agriculture in Northern EuropeCraig, O.E., Steele, Valerie J., Fischer, Anders, Hartz, S., Andersen, S.H., Donohoe, P., Glykou, A., Saul, H., Jones, D.M., Koch, E., Heron, Carl P. January 2011 (has links)
No / Farming transformed societies globally. Yet, despite more than a century of research, there is little consensus on the speed or completeness of this fundamental change and, consequently, on its principal drivers. For Northern Europe, the debate has often centered on the rich archaeological record of the Western Baltic, but even here it is unclear how quickly or completely people abandoned wild terrestrial and marine resources after the introduction of domesticated plants and animals at approximately 4000 calibrated years B.C. Ceramic containers are found ubiquitously on these sites and contain remarkably well-preserved lipids derived from the original use of the vessel. Reconstructing culinary practices from this ceramic record can contribute to longstanding debates concerning the origins of farming. Here we present data on the molecular and isotopic characteristics of lipids extracted from 133 ceramic vessels and 100 carbonized surface residues dating to immediately before and after the first evidence of domesticated animals and plants in the Western Baltic. The presence of specific lipid biomarkers, notably omega-(o-alkylphenyl)alkanoic acids, and the isotopic composition of individual n-alkanoic acids clearly show that a significant proportion ( approximately 20%) of ceramic vessels with lipids preserved continued to be used for processing marine and freshwater resources across the transition to agriculture in this region. Although changes in pottery use are immediately evident, our data challenge the popular notions that economies were completely transformed with the arrival of farming and that Neolithic pottery was exclusively associated with produce from domesticated animals and plants.
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Distinguishing wild ruminant lipids by gas chromatography/combustion/isotope ratio mass spectrometryCraig, O.E., Allen, R.B., Thompson, A., Stevens, R.E., Steele, Valerie J., Heron, Carl P. January 2012 (has links)
No / RATIONALE: The carbon isotopic characterisation of ruminant lipids associated with ceramic vessels has been crucial for elucidating the origins and changing nature of pastoral economies. delta(13)C values of fatty acids extracted from potsherds are commonly compared with those from the dairy and carcass fats of modern domesticated animals to determine vessel use. However, the processing of wild ruminant products in pottery, such as deer, is rarely considered despite the presence of several different species on many prehistoric sites. To address this issue, the carbon isotope range of fatty acids from a number of red deer (Cervus elaphus) tissues, a species commonly encountered in the European archaeological record, was investigated. METHODS: Lipids were extracted from 10 modern red deer tissues obtained from the Slowinski National Park (Poland). Fatty acids were fractionated, methylated and analysed by gas chromatography/combustion/isotope ratio mass spectrometry (GCCIRMS). The delta(13)C values of n-octadecanoic acid and n-hexadecanoic acid, and the difference between these values (Delta(13)C), were compared with those from previously published ruminant fats. RESULTS: Nine of the ten deer carcass fats measured have Delta(13)C values of less than -3.3 per thousand, the threshold previously used for classifying dairy products. Despite considerable overlap, dairy fats from domesticated ruminants with Delta(13)C values less than -4.3 per thousand are still distinguishable. CONCLUSIONS: The finding has implications for evaluating pottery use and early pastoralism. The processing of deer tissues and our revised criteria should be considered, especially where there is other archaeological evidence for their consumption.
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The circulation and consumption of Red Lustrous Wheelmade Ware: petrographic, chemical and residue analysisKnappett, C., Kilikoglou, V., Steele, Valerie J., Stern, Ben January 2005 (has links)
Yes / Red Lustrous Wheelmade ware is one of the most recognisable classes of pottery from the Late Bronze Age of the east Mediterranean. Yet both its production source and the nature of its contents and use remain a source of some debate. These questions are tackled here through an intensive programme of scientific analysis involving 95 samples of Red Lustrous Wheelmade ware and related wares from seven sites in Turkey, Cyprus and Egypt. Petrography and instrumental neutron activation analysis are combined in the study of the ceramic fabrics, with a view to specifying the source of this ware; while gas chromatography and gas chromatography-mass spectrometry are used to analyse absorbed and visible residues in and on the sherd samples, in the hope of shedding light on vessel contents and possible use. The results of the fabric
analysis show the ware to be extremely homogeneous, indicative of a single source: northern Cyprus is at present the most likely candidate, although further analysis, particularly of clay samples from the region in question, would certainly be desirable. The residue analysis suggests that Red Lustrous Wheelmade ware might have been used to carry some kind of plant oils, possibly perfumed, and that in some instances the vessel interior was coated with beeswax as a sealant. / AHRC
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Analysis of partially carbonised residues from the Chiseldon Cauldrons by gas chromatography-mass spectrometry and gas chromatography-combustion-isotope ratio mass spectrometrySteele, Valerie J. January 2017 (has links)
No / During the micro-excavation of the cauldrons, residues were identified which appeared different from the surrounding soil and metal corrosion products. Thirty-seven of these residues from nine cauldrons and two significant fragments of incomplete cauldrons were analysed by gas chromatography-mass spectrometry (GC-MS) along with two samples of soil from the micro-excavation for comparison. The aim of the analysis was to determine whether these residues contained any organic material related to the use of the cauldrons, specifically lipids (fats, waxes, resins etc.) from the preparation of food or drink. Two of the samples from the cauldrons were also sent for compound specific carbon stable isotope analysis by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) to give a more precise identification of the residues.
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Red Lustrous Wheelmade ware: analysis of organic residues in Late Bronze Age trade and storage vessels from the eastern MediterraneanSteele, Valerie J., Stern, Ben 2017 June 1929 (has links)
Yes / Transport and storage vessels in Red Lustrous Wheelmade ware (RLWm ware) were traded across a large area of
the eastern Mediterranean for approximately 300 years (c. 1500–1200 BCE) during the Late Bronze Age
(c.1600–1000 BCE). The extreme consistency of the ceramic, in form, fabric, chemistry and mineralogy, points to
a single production source for the ware, which, although no kiln sites have been identified, is generally accepted
to have been on Cyprus. The aim of this study was to determine whether organic residues were present in this
very fine, dense ware, and to characterise the contents of RLWm ware vessels from different sites, contexts and
periods, and of different forms, to improve our understanding of the trade in this ceramic type. To that end, 101
RLWm ware sherds, together with three visible residues, were examined from sites in Turkey, Cyprus, Egypt and
Syria. Residues were identified in more than half of the samples, indicating that organic material is absorbed into
and preserved in this very fine fabric. Four commodities were identified: fat (probably plant oil), which in four
residues was identified further as castor oil; beeswax; bitumen; and Pinaceae spp. resin. The commodities were
found alone or, occasionally, one of the latter three was combined with the fat or oil. Fatty material was the only
commodity present at all sites and its wide distribution may indicate that generally the vessels were used for a
mixture or mixtures based on plant oils, in some cases containing castor oil. It was impossible to determine
whether the beeswax, bitumen and resin formed part of this mixture or represented post-firing treatments of the
ceramic to make it less porous. The identification of more than one type of residue indicates that RLWm ware
vessels did not always contain the same commodity. No significant correlation could be detected between the
vessel forms, and the dating of many of the sherds was not precise enough to reveal any variation through time.
The type of residue present did vary depending on the geographical location of its final use. Beeswax was, with
two exceptions, only present in samples from Turkey, while bitumen was found exclusively in samples from
Cypriot sites. The occurrence of at least one example of every commodity in the samples from Cyprus is consistent
with the theory that this ware was manufactured on Cyprus, and indicates that the vessels could also have
been filled and exported from there. The variation in content of the vessels found in different geographical areas
could highlight a special trading relationship between the Hittite heartland in Turkey and the Cypriot potters
who produced the ware, and a possible trade in bitumen as a raw material between the north Syrian coastal area
of Ugarit and Cyprus. / This research was funded by an AHRC PhD studentship (number 110786), awarded to V. Steele.
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Sudskomedicinski aspekti promene koncentracije etanola u biološkim uzorcima čuvanim u kontrolisanim laboratorijskim uslovima / Medicolegal aspects of ethanol concetration changes in biological samples under controlled laboratory conditionsMaletin Miljen 20 September 2016 (has links)
<p>Određivanje koncentracije etanola u telesnim tečnostima, pre svega u krvi, neophodan je uslov da bi se ustanovio uticaj alkoholemije na psihomotorne sposobnosti. Poznavanje stabilnosti lekova, droga i metabolita u biološkim uzorcima je od ključne važnosti kada se ukaže potreba za ponovljenom analizom i evaluacijom rezultata u sudskom postupku. Osnovni ciljevi ovog rada su da se uz pomoć HS-GC metode (hedspejs gasna hromatografija) ustanovi da li postoji statistički značajna promena koncentracije etanola u uzorcima krvi dobijenih od živih osoba i u biološkim uzorcima uzorcima sa autopsijskog materijala. Na osnovu rezultata potrebno je bilo utvrditi u kojem tipu uzorka uzetog sa lešnog materijala postoji najmanja promena koncentracije tokom perioda čuvanja uzorka. Istraživanje je bilo otvoreno, randomizirano i prospektivnog tipa. Biološki uzorci krvi krvi živih osoba i lešnog materijala (krv, mokraća i staklasto telo) uzimani su metodom slučajnog izbora, u rasponu alkoholemije od 0,1 mg/ml do 5 mg/ml. Nakon inicijalne dvostruke analize, jedan biološki uzorak čuvan je u trajanju od 180 dana, dok je drugi otvaran i analiziran nakon 60, 120 i 180 dana. Ukupan broj analiza alkoholemije u krvi živih osoba iznosio je 500. Ukupan broj analiza koncentracije etanola u krvi, mokraći i staklastom telu sa leševa iznosio je 360. Etanol je u uzorcima krvi živih osoba, kao i u biološkim uzorcima sa autopsijskog materijala određivan metodom HS GC. Tokom čuvanja bioloških uzoraka u periodu od šest meseci ustanovljeno je da je došlo do značajnog smanjenja koncentracije etanola u svim analiziranim uzorcima, nezavisno od njegovog porekla. Promena koncentracije etanola tokom čuvanja u zavisnosti je od tkivne vrste uzorka, inicijalne alkoholemije, dužine čuvanja, integriteta vijala i čepova, temperature, odnosa tečne i gasne faze, prisustva konzervansa i potencijalnog intermitentnog otvaranja radi analiza.</p> / <p>Determination of ethanol concentration in body fluids, especially blood, is a necessary objective to establish the influence of alcohol on psychomotor skills. Knowing the stability of medicines, drugs and metabolites in biological samples is of crucial importance when there is a need for repeated analysis and result evaluation in court. The main objectives of this work were to determine whether there was a statistically significant change in ethanol concentration in blood samples obtained from living subjects and from autopsy material, by using HS-GC method (headspace gas chromatography). Based on the results it was necessary to determine which type of sample collected from autopsy showed the lowest change in concentration during the storage period. The study was open, randomized and prospective. Biological samples of living person's blood and autopsy biological samples (blood, urine and the vitreous humor) were taken at random, in the level range between 0.1 mg/ml and 5 mg/ml. After an initial duplicate analysis, one biological sample was stored for a period of 180 days, while the other was opened and analyzed after 60, 120 and 180 days. Total number of analysis of living person's blood samples was 500. The total number of analysis of autopsy biological samples was 360. All concentrations were determined by HS-GC method. During the storage, results showed that there has been a significant decrease in the concentration of ethanol in all of the analyzed samples, regardless of its origin. The level of this change was dependent on the type of tissue sample, initial alcohol concentration, duration of storage, integrity of the vials and stoppers, temperature, ratio of liquid and gas phases, presence of preservatives and intermittent opening for analysis.</p>
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Organic residue analysis of Red Lustrous Wheelmade Ware vessels traded across the eastern Mediterranean during the Late Bronze AgeSteele, Valerie J. January 2008 (has links)
Red Lustrous Wheelmade Ware (RLWm ware) transport and storage vessels have been excavated from Late Bronze Age (LBA) sites across the eastern Mediterranean. These distinctive vessels were traded for the valuable commodity they contained so far unidentified. Seventy-three sherds (61 RLWm ware, 12 in local fabrics) and two visible residues were analysed for organic residues using standard lipid extraction techniques. Seven residues from a previous study were re-examined. Gas chromatography-mass spectrometry identified four materials - beeswax, bitumen, fat/oil and resin. Beeswax, found only in vessels from Hittite sites in Turkey, was probably used as a post-firing treatment. Fat/oil, present in some sherds from every site, represents the contents of the vessels and showed many of the characteristics of degraded plant oil. Two examples contained a plant sterol and three yielded ricinoleic acid, a biomarker for castor oil. Gas-chromatography compound-specific isotope ratio mass spectrometry of selected residues excluded dairy products, ruminant animal fats and fish oils as source materials for the fats/oils, while comparison with a small database of modern oils created during this study does not exclude plant oils. Selected samples analysed by high performance liquid chromatography-tandem mass spectrometry did not reveal wine residues. Data on the elemental composition of the fabric collected during another study was re-analysed and compared with data from a further published study, confirming the remarkable consistency of RLWm ware fabric. Volume calculations were also attempted to give an estimate of the capacity of the main vessel forms.
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Avaliação da exposição ocupacional a praguicidas organofosforados em estufas de flores na região do Alto Tietê - São Paulo / Evaluation of occupational exposure to organophosphate pesticides in greenhouses of flower in the Alto Tietê region, state of S. Paulo, BrazilColasso, Camilla Gomes 12 September 2011 (has links)
O estado de São Paulo é responsável por 70% da produção nacional de flores e plantas ornamentais. Esses cultivos ocupam 7,5 mil hectares e mais da metade desta área é cultivada em estufas. Atualmente existem aproximadamente 8 mil produtores de pequeno, médio e grande porte em todo Brasil e este setor gera em torno de 200 mil empregos diretos, abrangendo produção e comércio. As estufas são microcosmos planejados para propiciar as condições ambientais adequadas ao crescimento de plantas. Qualquer infestação é controlada usando praguicidas que, devido ao enclausuramento e ajustes das condições climáticas, podem prolongar e intensificar a exposição ocupacional aos mesmos. Alguns estudos sugerem que os trabalhadores de estufas de flores e plantas ornamentais estão expostos a níveis mais elevados de praguicidas durante o carregamento, mistura e aplicação dos praguicidas, bem como pelo contato contínuo com as flores e plantas ornamentais, quando comparados a outros trabalhadores que entram em contato com essa classe de compostos. No presente trabalho, objetivou-se conhecer o processo de trabalho, práticas de saúde, higiene e segurança e localizar possíveis fontes de exposição ocupacional a praguicidas nas estufas de flores da região do Alto Tietê, e também otimizar métodos analíticos para a detecção e quantificação de praguicidas organofosforados (diclorvós, metil-paration e metidation) em patches de algodão e em tubos coletores XAD-2, com o intuito de analisar a exposição ocupacional dérmica e inalatória. O processo de avaliação incluiu o acompanhamento da jornada de trabalho, entrevistas e aplicação de questionários de trabalhadores de 18 estufas. Destas 18 foram selecionadas 6 estufas para coleta de amostras. Os organofosforados diclorvós, metidation e metilparation foram detectados e quantificados por cromatografia gasosa/espectrometria de massas (GC-MS), operado no modo de ionização por impacto de elétrons. Os dados da avaliação qualitativa demonstraram percentual elevado de desconhecimento das práticas adequadas de saúde, higiene e segurança para a utilização destes compostos, sugerindo que há risco de exposição durante a manipulação, armazenamento e descarte dos mesmos. Os limites de quantificação (LQ) obtidos foram abaixo de 0,4 ng/mL e limites de detecção (LD) foram abaixo de 0,1 ng/mL para todos os compostos. O método mostrou boa linearidade na concentração estudada (LSQ-500 ng/mL), com coeficiente (r) maior que 0,99. A precisão foi avaliada pelo desvio padrão relativo e apresentou valores inferiores a 15% para todos os compostos estudados. Após os métodos serem validados, foi realizada a amostragem dérmica e do ar e encontraram-se concentrações variadas de praguicidas. / The state of São Paulo - Brazil, accounts for 70% of domestic production of flowers and ornamental plants. Currently, these crops occupy 7.5 thousand hectares and over 50% of this area is cultivated in greenhouses. This market has an average of 8.000 producers and generates around 200.000 jobs. Greenhouses are microcosms designed to provide environmental conditions suitable for plant growth. Infestation is controlled using pesticides that due to the closure and adjustment to the weather conditions can prolong and intensify the exposure to them. Some studies suggest that workers in greenhouses of flowers and ornamental plants are exposed to higher levels of pesticides during loading, dilution and application, as well as by continuous contact with flowers and ornamental plants, when compared to other workers who enter in contact with this class of compounds. The aim of the present was to know the work process, to survey the practices of health, hygiene and safety standards and locate possible sources of occupational exposure to pesticides in greenhouses of flowers in the Alto Tietê region (São Paulo state), and to optimize analytical methods for detection and quantification of organophosphate pesticides (dichlorvos, methyl parathion and methidathion) in patches of cotton and in XAD-2 sorbent tubes, with the aim of analyzing the occupational dermal and inhalation exposure. The evaluation process included the monitoring of the working day, interviews and questionnaires, and samples collected in greenhouses. The organophosphorus compounds were detected and quantified by gas chromatography/mass spectrometry (GC-MS) operated in electron impact ionization. The data show a high percentage of lack of appropriate health practices, hygiene and safety for pesticide use suggests that there is risk of exposure during handling, storage and disposal of them. The limits of quantification (LOQ) obtained were below 0.4 ng/mL and limits of detection (LOD) were below 0.1 ng/mL for all compounds. The method showed good linearity in the studied concentration (LOQ-500 ng/mL), with coefficient (r) greater than 0.99. The precision was evaluated by relative standard deviation and showed values below 15% for all compounds studied. After the methods are validated, the dermal and air sampling was performed and a great range of pesticide concentrations was found. So it is evident that this study is valuable for future analysis and guidance to workers about possible hazards and proper use for reducing exposure to these compounds.
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