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"Metodologia para determinação de biomarcadores geoquímicos orgânicos em sedimentos - Hidrocarbonetos Alifáticos e Aromáticos, Esteróis e Alquenonas" / "Methodology for determination of organic geochemistry biomarkers in sediment - Aliphatic hydrocarbons, PAHs, Sterols and Alkenones"Lourenço, Rafael André 18 June 2003 (has links)
O destino de grande parte da matéria orgânica presente nos oceanos é o sedimento marinho. Essa matéria orgânica, que vai sendo armazenada ao longo dos anos, produz uma reserva única de informações sobre os processos biogeoquímicos ocorridos no passado e como esses processos responderam às mudanças ambientais. Certas moléculas orgânicas são sintetizadas apenas por organismos marinhos ou somente por plantas superiores terrestres. A abundância relativa desses compostos em sedimentos marinhos pode ser usada para determinar a contribuição de matéria orgânica terrestre ou marinha que foi depositada. Outros compostos, cujas fontes naturais são raras ou inexistem, encontrados em sedimentos, refletem a influência antrópica no meio. Há ainda compostos, com origem biológica especifica, cujas estruturas são influenciadas pelo controle enzimático dos organismos que os produzem, que são influenciados pelo meio. Esses compostos, cuja presença pode fornecer evidências inequívocas da sua fonte ou informações sobre condições oceanográficas recebem o nome de marcadores biológicos e são comumentemente abreviados como biomarcadores. Esse trabalho produziu uma metodologia analítica para identificação e quantificação de biomarcadores como os hidrocarbonetos alifáticos, hidrocarbonetos policíclicos aromáticos, esteróis e alquenonas através de uma única extração lipídica. Essa metodologia foi avaliada por diversos critérios analíticos e validada através de materiais de referência e de exercícios de comparação entre laboratórios. A metodologia foi aplicada em um testemunho de sedimento marinho obtido em Cabo Frio. A quantificação das alquenonas nas amostras do testemunho permitiu estimar a variação da temperatura da superfície oceânica ao longo dos anos e correlacioná-la com variações na intensidade da ressurgência, além de permitir verificar como os demais biomarcadores variaram em função da variação da temperatura do meio onde foram sintetizados. / The fate of most organic matter in the oceans is the marine sediment. This preserved organic matter became an unique reservoir of information about the operation of biogeochemical processes in the geological past, and how these processes responded to environmental changes. Some molecules are only synthesized by sea organisms, others only by higher plants. The relative abundance among these compounds in sea sediments can be used to determine the source of the organic matter. Other organic compounds, without natural sources, are an indicative of anthropogenic influence. The marine sediment also can accumulate compounds with the specific biological sources, which structures are influenced by the enzymatic control of the precursor organisms. All of these compounds, which can provide clear evidences of its sources or information about oceanographic conditions, are called biological markers or biomarkers. The present work put out an analytic method to identify and quantify biomarkers like aliphatic hydrocarbons, PAHs, sterols and alkenones with only one lipidic extraction. This method was evaluated by several analytic criteria and validated by reference material and by interlaboratory comparison study. The method was used to analyze a marine sediment core from Cabo Frio. The alkenones quantification in this core allowed not only appreciate changes in the sea surface temperature (SST) along the years and correlate them with changes in the upwelling, but also verify how the other biomarkers responded to SST changes.
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"Metodologia para determinação de biomarcadores geoquímicos orgânicos em sedimentos - Hidrocarbonetos Alifáticos e Aromáticos, Esteróis e Alquenonas" / "Methodology for determination of organic geochemistry biomarkers in sediment - Aliphatic hydrocarbons, PAHs, Sterols and Alkenones"Rafael André Lourenço 18 June 2003 (has links)
O destino de grande parte da matéria orgânica presente nos oceanos é o sedimento marinho. Essa matéria orgânica, que vai sendo armazenada ao longo dos anos, produz uma reserva única de informações sobre os processos biogeoquímicos ocorridos no passado e como esses processos responderam às mudanças ambientais. Certas moléculas orgânicas são sintetizadas apenas por organismos marinhos ou somente por plantas superiores terrestres. A abundância relativa desses compostos em sedimentos marinhos pode ser usada para determinar a contribuição de matéria orgânica terrestre ou marinha que foi depositada. Outros compostos, cujas fontes naturais são raras ou inexistem, encontrados em sedimentos, refletem a influência antrópica no meio. Há ainda compostos, com origem biológica especifica, cujas estruturas são influenciadas pelo controle enzimático dos organismos que os produzem, que são influenciados pelo meio. Esses compostos, cuja presença pode fornecer evidências inequívocas da sua fonte ou informações sobre condições oceanográficas recebem o nome de marcadores biológicos e são comumentemente abreviados como biomarcadores. Esse trabalho produziu uma metodologia analítica para identificação e quantificação de biomarcadores como os hidrocarbonetos alifáticos, hidrocarbonetos policíclicos aromáticos, esteróis e alquenonas através de uma única extração lipídica. Essa metodologia foi avaliada por diversos critérios analíticos e validada através de materiais de referência e de exercícios de comparação entre laboratórios. A metodologia foi aplicada em um testemunho de sedimento marinho obtido em Cabo Frio. A quantificação das alquenonas nas amostras do testemunho permitiu estimar a variação da temperatura da superfície oceânica ao longo dos anos e correlacioná-la com variações na intensidade da ressurgência, além de permitir verificar como os demais biomarcadores variaram em função da variação da temperatura do meio onde foram sintetizados. / The fate of most organic matter in the oceans is the marine sediment. This preserved organic matter became an unique reservoir of information about the operation of biogeochemical processes in the geological past, and how these processes responded to environmental changes. Some molecules are only synthesized by sea organisms, others only by higher plants. The relative abundance among these compounds in sea sediments can be used to determine the source of the organic matter. Other organic compounds, without natural sources, are an indicative of anthropogenic influence. The marine sediment also can accumulate compounds with the specific biological sources, which structures are influenced by the enzymatic control of the precursor organisms. All of these compounds, which can provide clear evidences of its sources or information about oceanographic conditions, are called biological markers or biomarkers. The present work put out an analytic method to identify and quantify biomarkers like aliphatic hydrocarbons, PAHs, sterols and alkenones with only one lipidic extraction. This method was evaluated by several analytic criteria and validated by reference material and by interlaboratory comparison study. The method was used to analyze a marine sediment core from Cabo Frio. The alkenones quantification in this core allowed not only appreciate changes in the sea surface temperature (SST) along the years and correlate them with changes in the upwelling, but also verify how the other biomarkers responded to SST changes.
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Provtagning av trädkärnor för att bedöma föroreningsgraden av klorerade lösningsmedel i grundvatten / Tree Core Sampling to Assess the Degree of Chlorinated Solvent Contamination in GroundwaterNordborg, Daniel January 2006 (has links)
<p>Chlorinated aliphatic hydrocarbons (CAH´s) were used widely within dry cleaning facilities and for metal degreasing until their toxicity was discovered. PCE is still used as dry cleaning liquid. Today CAH´s are found in soil environment at places where they have been used in the past. The CAH-concentration in trees growing on contaminated land has quite recently received attention as a cheap and effective way of assessing the extent of a CAH-contamination. The method has however, not been put into use in Sweden.</p><p>The aim of the study has been to investigate whether the CAH-concentration in tree cores could be used to delineate the spread of CAH in a soil environment under Swedish conditions in different seasons. The aim has also been to gain an understanding of the uptake process, as well as to identify the limitations of the method and important issues to consider when sampling.</p><p>Trees were sampled in March and June on Helgö 1:25, 1:26 in Växjö, Småland. Metal degreasing earlier conducted at this site has lead to the CAH contamination of soil and groundwater (PCE, TEC c-DACE). Mostly PCE, TCE, and chloroform were detected in tree cores. The CAH concentration was higher in June. Using the sum of PCE+TCE+c-DCE in trees to delineate the spread gave a result that was quite consistent with a delination done based on groundwater sampling.</p><p>The uptake of CAH by trees is governed by the uptake of water at the root. The water usage, together with the origin of the water used is important for the ability of the tree to take up CAH. The CAH concentration within trees is also dependent on the chemical properties of the compound (Log kow, solubility etc), the concentration of the compound in the soil as well as degradation processeses. The position and height of sampling in the trees, tree species as well as tree size are important factors to consider when sampling. Sampling during summer is preferred when the concentration of CAH in trees is likely to be higher.</p><p>The analysis of CAH in tree cores has potential to be used as a screening tool in soil investigations under Swedish conditions. It is a cheap and easy to use method, which would be a good complement to other investigative measures. However, an increased understanding of the processes involved, together with more analysis are needed., as this is a new method.</p> / <p>Klorerade lösningsmedel (CAH) användes i stor omfattning som bl a kemtvättmedel och avfettningsmedel tills dess att deras toxiska egenskaper blev kända. Perkloretylen (PCE) används än idag som kemtvättmedel. CAH återfinns ofta i markmiljö på de platser där de tidigare använts. Analys av CAH-koncentration i trädkärnor har uppmärksammats som en billig och effektiv metod för att översiktligt bedöma utbredningen av dessa föroreningar. Metoden har inte tidigare använts i Sverige.</p><p>Syftet med detta examensarbete är att undersöka om trädprovtagning kan användas för att bedöma utbredningen av föroreningar i markmiljö under svenska förhållanden vid olika årstider.</p><p>Analyserade CAH-halter i träd har jämförts med tidigare registrerade halter av CAH i grundvatten. Syftet har också varit att beskriva CAH-upptaget i träd, undersöka metodens begränsningar samt att sammanfatta viktiga aspekter vid provtagning.</p><p>Provtagningar av träd har genomförts under mars och juni på fastigheterna Helgö 1:25 och 1:26 i Växjö, där tidigare metallavfettning har medfört att mark och grundvattnet förorenats av CAH; perkloretylen (PCE), trikloretylen (TCE) och nedbrytningsprodukten dikloretylen (c1,2-DCE). Vid analys av trädkärnor detekterades främst PCE, TCE samt TCM (kloroform). Koncentrationen av CAH var högre i juni. Halten PCE+TCE+c-DCE i trädproverna gav en översiktlig bild av föroreningssituationen som överensstämde väl med de grundvattenprover som tidigare tagits på fastigheten.</p><p>CAH tas upp i vattenlöst fas vid trädens rötter. Trädets vattenbehov och vilket vatten det utnyttjar är därför viktigt för dess möjlighet att ta upp CAH. Ämnets kemiska egenskaper (log kow, flyktighet, mm.), samt förekomst och nedbrytning påverkar den halt som registreras i trädet. Vid provtagning bör provtagningspunkternas höjd över marken och position, trädart samt trädstorlek beaktas. Provtagning under sommaren är att föredra eftersom halterna då är högre.</p><p>Jämförelsen med grundvattenprovtagning visar att metoden har potential att användas i Sverige för att bedöma utbredningen av en CAH-förorening i markmiljö. Den är enkel att använda och kan vara ett alternativ på platser där konventionella metoder är svåra att genomföra. En ökad förståelse för involverade processer, samt utökade undersökningar av metoden är nödvändiga då metoden är ny.</p>
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Estudo de hidrocarbonetos e metais em sedimentos de fundo do Rio Negro na orla urbana de ManausLopes, Alcinei Pereira 23 September 2010 (has links)
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Previous issue date: 2010-09-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The waters of the Rio Negro, in the border city of Manaus, receives large amounts of domestic and industrial waste from its main tributaries (Tarumã-Acu, Sao Raimundo, Pupils and Puraquequara) that may be compromising their natural
features (water, plants, sediments and etc.). Due the ability to accumulate organic and inorganic compounds, the bottom sediments are used to assess the contamination levels of aquatic environments. As a result, we determined the concentrations of aliphatic hydrocarbons, polycyclic aromatic hydrocarbons (PAH) and potentially toxic metals (MPT) in ten samples of bottom sediments collected in March 2009 in
the confluence between the Rio Negro and major watersheds the city of Manaus. The aim of study was to classify the origin and level of contamination of these compounds. In the determination of hydrocarbons, sediments were freeze dried,
extracted with hexane, fractionated by open column liquid chromatography. The determination of aliphatic hydrocarbons was performed by GC-FID and the PAH by GC-MS. After digestion with aqua regia the MPT (Al, Fe, Zn, Cu, Ni, Cr, Pb, Cd and Mn) in total fraction of sediments were determined by ICP-OES. The results showed that concentrations of total aliphatic hydrocarbons were 13.4 to 448 mg g-1, and the
sum of 38 PAHs was 58.8 to 6832 ng g-1. These values are considered high for natural aquatic environments that have not suffered oil spill accidents. Among the metals determined Al (32 091 mg kg-1) and Fe (35 474 mg kg-1) were those with the
highest concentrations.The sediments that received the largest anthropogenic contribution were those collected at the entrance of the basin of the streams São Raimundo and Educandos. The diagnosis index hydrocarbons the origin of in sediments showed a predominance of mixed sources and petrogenic sources in most seasons / As águas do rio Negro na orla urbana de Manaus recebem grande quantidade de resíduos domésticos e industriais de seus principais afluentes (Tarumã-Açu, São Raimundo, Educandos e Puraquequara) que podem estar comprometendo suas
características naturais (água, plantas, sedimentos e etc). Por ter a capacidade de acumular compostos orgânicos e inorgânicos, os sedimentos de fundo são utilizados na avaliação dos níveis de contaminação de ambientes aquáticos. Em virtude disso, foram determinados as concentrações de hidrocarbonetos alifáticos, hidrocarbonetos policíclicos aromáticos (HPA) e metais em dez amostras de sedimentos de fundo, coletadas em março de 2009 nas confluências entre o rio Negro e as principais bacias de drenagem da cidade de Manaus. O estudo tem o objetivo de classificar a origem e o nível de contaminação destes compostos. Nas determinações de hidrocarbonetos,
os sedimentos foram liofilizados, extraídos em soxhlet, fracionados por cromatografia líquida de coluna aberta. A determinação de hidrocarbonetos alifáticos foi realizada por CG-DIC e os HPA por CG-EM. Apos digestão com água régia, os
metais (Al, Fe, Zn, Cu, Ni, Cr, Pb, V, Cd e Mn) presentes na fração total dos sedimentos foram determinados por ICP-OES. Os resultados mostraram que as concentrações dos hidrocarbonetos alifáticos totais foram de 13,4 a 448 μg g-1, e a
somatória dos 38 HPA foi de 58,8 a 6832 ng g-1. Esses valores são considerados elevados para ambientes aquáticos naturais que não sofreram acidentes de derrame de óleo. Entre os metais determinados o Al (32091 mg kg-1) e o Fe (35474 mg kg-1) foram os que apresentaram as maiores concentrações. Os sedimentos que receberam a maior contribuição antrópica foram daqueles coletados na entrada da bacia dos igarapés São Raimundo e Educando. Os índices de diagnósticos da origem de
ix hidrocarbonetos nos sedimentos mostraram predominância de fontes petrogênica e fontes mistas na maioria das estações.
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Cometabolic biodegradation of halogenated aliphatic hydrocarbons by ammonia-oxidizing microorganisms naturally associated with wetland plant rootsQin, Ke January 2014 (has links)
No description available.
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FTIR emission studies of chemical processesMorrell, Claire January 2000 (has links)
No description available.
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Hidrocarbonetos alif?ticos em sedimentos de fundo do estu?rio do Rio Potengi, grande Natal (RN): implica??es ambientaisCarrascoza, L?gia Soares 07 February 2011 (has links)
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Previous issue date: 2011-02-07 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The Potengi river estuary is located in the region of Natal (RN, Brazil), comprising a population of approximately 1,000,000 inhabitants. Besides the dominant urban presence, the estuary has fragments of mangrove forest. The objective of this study is to determine the aliphatic hydrocarbons found in the bottom sediments of this estuary, identifying their levels, distribution and their possible origins through the diagnostic rates, indexes and results comparisons with the local anthropic and natural characteristics. The samples were obtained according to a plan that allowed sampling of the estuary up to 12 km upstream from it as mounth. 36 stations were selected, grouped into 12 cross sections through the course of the river and spaced on average by 1 km. Each section consisted of three stations: the right margin, the deepest point and the left margin. The hydrocarbon n-alkanes from C10 to C36, the isoprenoids pristane and phytane, the unresolved complex mixture (UCM) and the total resolved hydrocarbons were analyzed by gas chromatography. N-alkanes, pristane, phytane and UCM were detected only at some stations. In the other, the concentration was below the detection limit defined by the analytical method (0.1 mg / kg), preventing them from being analyzed to determine the origin of the material found. By using different parameters, the results show that the estuary receives both the input of petrogenic hydrocarbons, but also of biogenic hydrocarbons, featuring a mixture of sources and relatively impacted portions. Based on the characteristics and activities found in the region, it is possible to affirm that petrogenic sources related to oil products enter the estuary via urban runoff or boats traffic, boat washing and fueling. Turning to the biogenic source, the predominant origin was terrestrial, characterized by vascular plants, indicating contribution of mangrove vegetation. It was evident the presence of, at specific points in the estuary, hydrocarbon pollution, and, therefore is recommended the adoption of actions aimed at interrupting or, at least, mitigating the sources potentially capable of damp petrogenic hydrocarbons in the estuary studied. / O estu?rio do rio Potengi est? inserido na regi?o da Grande Natal (RN, Brasil), que compreende uma popula??o de aproximadamente 1.000.000 de habitantes. Al?m da presen?a urbana dominante, este estu?rio mant?m fragmentos de floresta de manguezal. O objetivo deste estudo foi determinar os hidrocarbonetos alif?ticos em sedimentos de fundo do estu?rio, identificando os n?veis, distribui??o e suas poss?veis origens atrav?s dos ?ndices, raz?es diagn?sticas e compara??o dos resultados com as caracter?sticas antr?picas e naturais vigentes no local. As amostras foram obtidas obedecendo a um plano de amostragem que permitiu uma varredura desde a foz do estu?rio at? 12 km a montante. Foram escolhidas 36 esta??es, agrupadas em 12 se??es transversais ao curso do rio espa?adas, em m?dia, por 1 km. Cada se??o era composta de tr?s esta??es: margem direita, ponto mais profundo e margem esquerda. Atrav?s da cromatografia gasosa, foram analisados os hidrocarbonetos n-alcanos do C10 ao C36, os isopren?ides pristano e fitano, a mistura complexa n?o resolvida (MCNR), al?m dos resolvidos totais. Foram detectados n-alcanos, pristano, fitano e MCNR apenas em algumas esta??es. Nas demais, a concentra??o foi inferior ao limite de detec??o estabelecido pelo m?todo anal?tico (0,1 mg/kg), impossibilitando-as de serem analisadas para a determina??o da origem do material encontrado. Atrav?s da utiliza??o de diferentes par?metros, os resultados demonstram que o estu?rio recebe tanto o aporte de hidrocarbonetos petrog?nicos, como tamb?m de hidrocarbonetos biog?nicos, caracterizando uma mistura de fontes e ?reas mais ou menos impactadas. Com base nas caracter?sticas e atividades encontradas na regi?o, podemos afirmar que as fontes petrog?nicas relacionam-se a derivados de petr?leo que entram no estu?rio atrav?s do escoamento urbano ou pelo tr?fego, lavagem e abastecimento de embarca??es; com rela??o ? fonte biog?nica, predominou origem terrestre caracterizado por plantas vasculares, indicando contribui??o da vegeta??o de mangue presente no local. Fica evidenciado o registro, em pontos espec?ficos do estu?rio, da polui??o por hidrocarbonetos, sendo recomendada a tomada de medidas objetivando a interrup??o ou, pelo menos, a atenua??o das fontes potencialmente capazes de aportar hidrocarbonetos petrog?nicos no estu?rio estudado
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Provtagning av trädkärnor för att bedöma föroreningsgraden av klorerade lösningsmedel i grundvatten / Tree Core Sampling to Assess the Degree of Chlorinated Solvent Contamination in GroundwaterNordborg, Daniel January 2006 (has links)
Chlorinated aliphatic hydrocarbons (CAH´s) were used widely within dry cleaning facilities and for metal degreasing until their toxicity was discovered. PCE is still used as dry cleaning liquid. Today CAH´s are found in soil environment at places where they have been used in the past. The CAH-concentration in trees growing on contaminated land has quite recently received attention as a cheap and effective way of assessing the extent of a CAH-contamination. The method has however, not been put into use in Sweden. The aim of the study has been to investigate whether the CAH-concentration in tree cores could be used to delineate the spread of CAH in a soil environment under Swedish conditions in different seasons. The aim has also been to gain an understanding of the uptake process, as well as to identify the limitations of the method and important issues to consider when sampling. Trees were sampled in March and June on Helgö 1:25, 1:26 in Växjö, Småland. Metal degreasing earlier conducted at this site has lead to the CAH contamination of soil and groundwater (PCE, TEC c-DACE). Mostly PCE, TCE, and chloroform were detected in tree cores. The CAH concentration was higher in June. Using the sum of PCE+TCE+c-DCE in trees to delineate the spread gave a result that was quite consistent with a delination done based on groundwater sampling. The uptake of CAH by trees is governed by the uptake of water at the root. The water usage, together with the origin of the water used is important for the ability of the tree to take up CAH. The CAH concentration within trees is also dependent on the chemical properties of the compound (Log kow, solubility etc), the concentration of the compound in the soil as well as degradation processeses. The position and height of sampling in the trees, tree species as well as tree size are important factors to consider when sampling. Sampling during summer is preferred when the concentration of CAH in trees is likely to be higher. The analysis of CAH in tree cores has potential to be used as a screening tool in soil investigations under Swedish conditions. It is a cheap and easy to use method, which would be a good complement to other investigative measures. However, an increased understanding of the processes involved, together with more analysis are needed., as this is a new method. / Klorerade lösningsmedel (CAH) användes i stor omfattning som bl a kemtvättmedel och avfettningsmedel tills dess att deras toxiska egenskaper blev kända. Perkloretylen (PCE) används än idag som kemtvättmedel. CAH återfinns ofta i markmiljö på de platser där de tidigare använts. Analys av CAH-koncentration i trädkärnor har uppmärksammats som en billig och effektiv metod för att översiktligt bedöma utbredningen av dessa föroreningar. Metoden har inte tidigare använts i Sverige. Syftet med detta examensarbete är att undersöka om trädprovtagning kan användas för att bedöma utbredningen av föroreningar i markmiljö under svenska förhållanden vid olika årstider. Analyserade CAH-halter i träd har jämförts med tidigare registrerade halter av CAH i grundvatten. Syftet har också varit att beskriva CAH-upptaget i träd, undersöka metodens begränsningar samt att sammanfatta viktiga aspekter vid provtagning. Provtagningar av träd har genomförts under mars och juni på fastigheterna Helgö 1:25 och 1:26 i Växjö, där tidigare metallavfettning har medfört att mark och grundvattnet förorenats av CAH; perkloretylen (PCE), trikloretylen (TCE) och nedbrytningsprodukten dikloretylen (c1,2-DCE). Vid analys av trädkärnor detekterades främst PCE, TCE samt TCM (kloroform). Koncentrationen av CAH var högre i juni. Halten PCE+TCE+c-DCE i trädproverna gav en översiktlig bild av föroreningssituationen som överensstämde väl med de grundvattenprover som tidigare tagits på fastigheten. CAH tas upp i vattenlöst fas vid trädens rötter. Trädets vattenbehov och vilket vatten det utnyttjar är därför viktigt för dess möjlighet att ta upp CAH. Ämnets kemiska egenskaper (log kow, flyktighet, mm.), samt förekomst och nedbrytning påverkar den halt som registreras i trädet. Vid provtagning bör provtagningspunkternas höjd över marken och position, trädart samt trädstorlek beaktas. Provtagning under sommaren är att föredra eftersom halterna då är högre. Jämförelsen med grundvattenprovtagning visar att metoden har potential att användas i Sverige för att bedöma utbredningen av en CAH-förorening i markmiljö. Den är enkel att använda och kan vara ett alternativ på platser där konventionella metoder är svåra att genomföra. En ökad förståelse för involverade processer, samt utökade undersökningar av metoden är nödvändiga då metoden är ny.
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