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Poly Brominated Diphenyl Ethers (PBDEs) are known flame retardants with highly persistent and lipophilic in nature. The continued usage of PBDE in various products amplifies the human burden of PBDEs. It is therefore, important to study the potential toxicological and/or biological effects of PBDE exposure in human. In this study we investigated the mode of action of PBDE induced toxicity in human liver by exposing human hepatocarcinoma cells in a time (24-72h) and dose (0-100μM) dependent manner. The highest test dose caused an inhibition in cell viability up to 50% after 72h, whereas lower doses (<50μM) showed slight increase in cell viability. Likewise, higher doses caused significant accumulation of intracellular ROS over time. Further, increase in caspase-3 enzyme levels and DNA fragmentation showed that, lower brominated PBDEs induce liver toxicity through accumulation of toxic metabolites and reactive oxygen species over time leading to caspase-mediated apoptotic cell death.

Phthalate esters (PEs) and organophosphate esters (OPEs) are common indoor pollutants frequently detected in environmental (dust, air), personal (hand wipes, diet) and human matrices (urine, serum etc.). In this thesis, mathematical models were used to establish links between intake and body burden for a comprehensive dataset based on a Norwegian study population. Also, the relative importance of different PE uptake pathways was assessed and discussed. Furthermore, the suitability of human nails as an alternative, non-invasive biomonitoring matrix for PEs was investigated. Additionally, information regarding alternative plasticizers to PEs was collected and presented extensively. Results showed that for PEs (paper II), daily intakes based on external exposure media agree with back-calculations using urinary metabolite concentrations, leading to the conclusion that human exposure for the general adult population is well understood and that the most important uptake routes were captured. Overall intake levels are comparable or lower than level presented in recent comprehensive studies and hazard quotients were well below 1 (low risk). As expected, diet was found to be the most important uptake route for all PEs. For lower molecular weight PEs, inhalation becomes a strong contributing pathway whereas for higher molecular weight PEs, dust ingestion was also important. Daily intake based on hand wipes was found to be much lower than the estimated total dermal intake based on air, dust and personal care products, questioning the relevance of hand wipes to represent total dermal exposure. Human nails were found to be unsuitable for replacing urine as a biomonitoring matrix for PEs as internal intake (from blood) cannot explain measured nail concentrations and uptake from air is too slow to reach observed concentrations within a realistic time frame (paper III). Hence, the kinetic links between intake and nail concentrations could not be established. Although exposure to traditional PEs is decreasing, use and body burden of some alternatives are increasing (paper I). Fortunately, most alternative plasticizers have favorable toxicological properties, resulting in low risk for humans. In contrast to PEs, OPEs still remain a group of poorly studied substances in terms of human exposure (paper IV). Due to lack of information regarding human metabolism, reliable links between intake and concentrations in serum and urine could not be established. Modelling results showed that concentrations in serum, and to some extent, urine, were underestimated for 2 compounds. It is likely that a combination of missing intake and suboptimal biomarkers were the cause for this under-prediction. Because of this, further studies regarding human metabolism should be performed for OPEs and potentially more specific biomarkers identified in the future. For PEs, there is a need for more comprehensive datasets to study exposure for high risk groups such as infants and children. Furthermore, dermal uptake remains poorly understood and the uptake of PEs into human nails should be studied in more detail to establish the kinetic links between exposure and body burden. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 4: Manuscript.</p>

Les retardateurs de flamme bromés sont des agents ignifuges utilisés dans de nombreux produits manufacturés. Les plus courants sont les polybromodiphényl éther (PBDE), le tétrabromo-bisphénol A (TBBPA) et l'hexabromocyclododécane (HBCD). Ces composés considérés comme des polluants organiques persistants (POPs) sont désormais retrouvés dans l'environnement et chez l'Homme, et sont suspectés, ainsi que leurs métabolites, d'être des perturbateurs endocriniens. Des développements analytiques basés sur la spectrométrie de masse ont été engagés afin d'étudier le métabolisme in vitro du TBBPA et des PBDE et rechercher les composés parents et leurs métabolites dans différents prélèvements d'origine humaine. Les métabolites formés chez l'Homme ont ainsi été identifiés comme étant des conjugués pour le TBBPA, et des dérivés hydroxylés, dihydrodiol et conjugués pour les PBDE. La plupart de ces métabolites ont été identifiés et quantifiés dans les fluides biologiques humains, démontrant ainsi l'exposition du foetus et du nouveau-né à ces composés, à des niveaux similaires à ceux retrouvé dans d'autres pays. D'un point de vue qualitatif, la présence de métabolites potentiellement actifs sur des cibles cellulaires a été mise en évidence, ainsi que le passage des résidus vers le lait (TBBPA, HBCD) et/ou au travers de la barrière placentaire (TBBPA et PBDE). Un métabolite spécifique, présent en importantes (octa-BDE hydroxylé) pourrait être un bon biomarqueur d'exposition, et son potentiel toxique devrait par ailleurs être étudié / Brominated Flame Retardants are widely used for the manufacture of fire-proofed industrial products and consumer goods. Major BFRs are polybromodiphenyl ether (PBDE), tetrabromobisphenol A (TBBPA) and hexabromocyclododecane (HBCD). Considered as persistent organic pollutants (POPs), they are detected in various environmental compartments and human samples. Parent compounds as well as several metabolites could act as endocrine disruptors. Methodological developments based on mass spectrometry, in vitro approaches (TBBPA, PBDE) and an extensive review of the available literature have been used to sharpen our current knowledge of the fate of BFR, and to identify both parent compounds and metabolite in human samples. Results obtained in vitro using human primary hepatocyte cultures as well as human cell lines show that human cells biotransform TBBPA into conjugated metabolites and PBDE into hydroxylated, dihydrodiol and conjugated metabolites. Those metabolites were detected in human samples, demonstrating foetal and newborn exposition. BFR and some of their metabolites, including bioactive compounds, are transferred through the placental barrier (TBBPA, PBDE) and/or into milk (TBBPA, HBCD). Even though the monitored concentration levels were found to be low, one of these metabolites, namely (OH-octaBDE) was found to be abundant in almost all serum samples, and appears to be a relevant candidate biomarker of exposure

La câblerie est un secteur industriel gros consommateur de polymères. Dans ce domaine, les normes imposent cependant de limiter le risque incendie et donc d'ignifuger les matériaux polymères utilisés, sources importantes de combustibles. De nombreux travaux ont porté sur leur ignifugation par utilisation d'additifs retardateurs de flammes, mais peu d'entre eux ont étudié l'influence de la morphologie des mélanges polymères chargés sur la stabilité thermique et le comportement au feu. Cette thèse fait suite à un précédent projet qui avait démontré une influence significative de la morphologie sur le comportement au feu d'un mélange polymère binaire (PC/PBT). Elle a pour but d'améliorer la compréhension de cette influence dans le cas de formulations plus complexes (ternaires ou quaternaires) à matrice éthylène méthylacrylate (EMA). Pour cela, la première stratégie adoptée a été l'identification d'un système ignifugeant comprenant un polyester capable de charbonner lors de l'ajout d'un RF. Une fois ce système identifié (PBT+MDH), il a été incorporé en matrice EMA en faisant varier la composition et la morphologie (dispersion sélective, taille des particules…). Cette approche a mis en évidence des différences significatives entre les différentes formulations et des résultats très intéressants ont été obtenus en termes de réaction au feu à l'échelle laboratoire. Cependant, le passage à l'échelle pilote (test de propagation de flamme) n'a pas permis de valider ces formulations pour des applications câbles. Au vu de ces constatations, une dernière partie a été proposée pour essayer d'améliorer la cohésion du résidu par ajout de polyphosphate d'ammonium. / The cable industry is a major consumer of industrial polymers. In this area, the standards impose to limit the fire risk and thus to enhance the fireproof of the polymeric materials which are important sources of fuel. Many studies have focused on their flame retardancy by using additive flame retardants, but few of them have studied the influence of the morphology of filled polymer blends on the thermal stability and the fire behavior. This thesis follows a previous project which demonstrated a significant influence of the morphology on the fire behavior of a binary polymer blend (PC / PBT). It aims to improve the understanding of this influence in the case of more complex formulations (ternary or quaternary) with ethylene methylacrylate (EMA) matrix. The first strategy was the identification of a flame retardant system including polyester that is able to char when a flame retardant is added. Once the system is identified (PBT + MDH), it was incorporated in EMA matrix by varying the composition and the morphology (selective dispersion, particle size ...). This approach showed significant differences between the different formulations and very interesting results have been obtained in terms of fire reaction at the laboratory scale. However, the scale-up approach (flame spread test) did not validate these formulations for cables applications. Therefore, the last part has been proposed to try to improve the cohesion of the residue by adding ammonium polyphosphate.

Os retardantes de chama bromados são substâncias utilizadas nos mais variados bens de consumo para aumentar sua resistência ao fogo e/ou altas temperaturas em casos de incêndio, aumentando assim, as chances de escape e reduzindo a gravidade das queimaduras. Para este fim os éteres difenílicos polibromados (PBDEs) representam a classe mais utilizada tendo em vista sua eficiência no controle da propagação da chama e seu baixo custo. Estes compostos se incluem entre os recentemente denominados contaminantes ambientais emergentes que apresentam uma carência de dados toxicológicos, principalmente em relação aos efeitos danosos e aos biomarcadores de exposição, além do potencial dano ao ambiente, sendo esta uma preocupação recente da comunidade científica. Pelo fato da mitocôndria ser reconhecida como a principal organela produtora de energia celular, além de exercer um papel fundamental na manutenção de inúmeras funções celulares, ela foi utilizada como modelo experimental para avaliar os efeitos dos congêneres de BDE- 100; -153; -154 e -209 na faixa de concentração de 0,1 ?mol/L a 50 ?mol/L. Nossos resultados mostram que os efeitos em mitocôndrias isoladas podem ocorrer em menores concentrações para os congêneres BDE-153; -154 (Hexa-BDE) e -209 (Deca-BDE) e em maiores concentrações para o BDE-100 (Penta-BDE). Desta forma, foi observado que os compostos possuem capacidade de interagir com membrana mitocondrial, induzir inchamento mitocondrial, desregular a homeostase cálcica e dissipar o potencial de membrana mitocondrial em concentrações diferentes, entretanto não são capazes de induzir estresse oxidativo na mitocôndria. Assim, os resultados indicam que a ação dos PBDEs sobre mitocôndrias pode ser um dos mecanismos de toxicidade desta classe de compostos. / The brominated flame retardants are substances used in various consumer goods to increase their fire resistance and / or higher temperatures in case of fire, thus increasing the chances of escape and reducing the severity of burns. To this end polybrominated diphenyls ethers (PBDEs) are the most used class in view of its efficiency in controlling the spread of flame and its low cost. These compounds are among the newly emerging environmental contaminants known to exhibit a lack of toxicological data, especially regarding the harmful effects and biomarkers of exposure and potential harm to the environment, which is a recent concern of the scientific community. Because the mitochondrion is recognized as the main energy-producing cell organelles, as well as play a vital role in the maintenance of many cellular functions, it was used as an experimental model to evaluate the effects of the congeners BDE-100 (Penta- BDE), -153, -154 (Hexa-BDE) and -209 (Deca-BDE), in concentration range ranging from 0.1 ?mol/L to 50 ?mol/L. The results show that the effects on isolated mitochondria may occur at lower concentrations for the BDE-153, -154 and -209 and high concentrations to the BDE-100. Thus, it was observed that the compounds have the ability to interact with mitochondrial membrane, inducing swelling, dysregulation of calcium homeostasis and dissipation of membrane potential at different concentrations, however they cannot change factors related to oxidative stress in mitochondria. Furthermore, the induction of mitochondrial swelling, and added significant depletion of ATP levels may contribute to the toxic effects observed. Thus, we conclude that the action of PBDESS on mitochondria is one of the mechanisms of toxicity of this class of compounds.

Made available in DSpace on 2014-06-11T19:31:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-12-18Bitstream added on 2014-06-13T19:01:11Z : No. of bitstreams: 1 campos_mf_dr_botib.pdf: 592742 bytes, checksum: 69c6b5935172801d218019ca8900bfe7 (MD5) / Tratamentos com reguladores vegetais foram estudados em plantas de soja (Glycine max (L.) Merrill cv. BRS-184) para avaliar o teor de clorofila das folhas, a altura da planta, o número de ramificações e altura de vagens. O experimento foi conduzido em casa de vegetação do Departamento de Botânica do Instituto de Biociências de Botucatu - UNESP. O delineamento experimental utilizado foi inteiramente casualizado, com três repetições e oito tratamentos (testemunha; GA3 100 mg L-1; BAP 100 mg L-1; IBA 100 mg L-1; Stimulate® (IBA+GA3+Cinetina) 20 mL L-1; cloreto de mepiquat 100 mg L-1; cloreto de mepiquat 100 mg L-1+BAP 100 mg L-1+IBA 100 mg L-1 e ethephon 600 mg L-1. Os tratamentos foram aplicados três vezes, espaçados em 30 dias durante o ciclo da planta a partir do 43º dia e foram realizadas seis avaliações espaçados em 13 dias. Os tratamentos com BAP, ethephon e cloreto de mepiquat + IBA + BAP mantiveram o teor de clorofila nas folhas alto até o final do ciclo da planta. A altura de plantas foi menor que a testemunha em todos os tratamentos a partir de 90 dias após a semeadura, com exceção do tratamento com GA3, que manteve a altura de plantas superior durante todo ciclo da cultura. As ramificações das plantas foram incrementadas pelo tratamento com ethephon, que apresentou, a altura da primeira vagem inferior à testemunha. No tratamento com GA3, a altura da primeira vagem foi superior. / Treatments with plant growth regulators were studied in soybean plants (Glycine max (L.) Merrill cv. BRS-184) to assess the leaf chlorophyll content, the ramification number and the height of the pods. The experiment has been carried out at the greenhouse of the Botanic Department, Bioscience Institute, University of the Sao Paulo State – UNESP, campus of Rubiao Junior, Botucatu, Brazil. The used experimental design delineation was completely randomized block with three replications and eight treatments (control; GA3 100 mg L-1; BAP 100 mg L-1; IBA 100 mg L-1; Stimulate® (IBA+GA3+Cinetin) 20 mL L-1; mepiquat chloride 100 mg L-1; mepiquat chloride 100 mg L-1+BAP 100 mg L-1+IBA 100 mg L-1 and ethephon 600 mg L-1. The treatments were applied three times every 30 days during the plant cycle after 43 days and six evaluations have been made every 13 days. The treatments with BAP, ethephon and mepiquat chloride + IBA + BAP maintained the high chlorophyll content until the end of the plant cycle. The height of the plants was lower than the control in all treatments after the 90th day of sowing, excepting the treatment with GA3, which maintained the height of the plants during the cycle of cultivation. The plant stems were increased by the ethephon treatment; however, the height of the first pod was the lowest in this treatment and the highest in the treatment with GA3.

Made available in DSpace on 2017-07-10T17:37:09Z (GMT). No. of bitstreams: 1 Rodolfo Linzmeyer Junior.pdf: 279846 bytes, checksum: c3e7ee405de065b8db63f85192354d12 (MD5) Previous issue date: 2006-09-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The soybean presents well-known importance in the national chain of production of grains, currently it is the main Brazilian agricultural product justifying investments in technology aiming at the increase of the yield and reduction of the adverse factors to the crop. Thus, the present work if considers to evaluate the effect of the vegetal retardant use in different densities of sowing on the growth, components of yield, productivity and fallen plant index in the crop of the soybean to cultivate CD 209. The experiment was developed in the Technological Center Coopavel in the city of Cascavel PR. For in such a way, no tillage system was become fullfilled. The experimental design was arranged in randomized complete blocks, with four replications, in factorial outline (6X2), being the treatments gotten for the combination of six levels of the vegetal retardant Etil Trinexapac (0,0 0,2 0,4 0,6 0,8 and 1,0 L ha-1) and two densities of sowing (14 and 18 plants M-1). Evaluations with frequency of 14 days had been carried through, from the 21 days after the emergency (DAE) until the full bloom of the crop, getting themselves the diameter of stem and the height of canopy of the plants. Also three destructive collections to the 35 had been carried through, 70 and 100 DAE for attainment of dry matter in the different parts of the plant and leaf area. In the harvest the components of the yield had been evaluated, productivity and fallen plant index. The vegetal retardant and the densities of sowing had influenced directly in the height and the diameter of stem of the plants. For dry matter, components of the yield, productivity and fallen plant index did not have influence; however the leaf area were influenced by the sowing density / A soja apresenta notória importância na cadeia nacional de produção de grãos, atualmente é o principal produto agrícola brasileiro justificando investimentos em tecnologia visando o aumento da produtividade e redução dos fatores adversos à cultura. Assim, o presente trabalho se propõe a avaliar o efeito da utilização de retardante vegetal em diferentes densidades de semeadura sobre o crescimento, componentes de produção, produtividade e acamamento na cultura da soja cultivar CD 209. O experimento foi desenvolvido no Centro Tecnológico Coopavel no município de Cascavel PR. Para tanto, realizou-se plantio direto na palha. O delineamento experimental constitui-se de blocos inteiramente casualizados com quatro repetições, em esquema fatorial (6X2), sendo os tratamentos obtidos pela combinação de seis doses do retardante etil trinexapac (0,0 0,2 0,4 0,6 0,8 e 1,0 L ha-1) e duas densidades de semeadura (14 e 18 plantas m-1). Foram realizadas avaliações com freqüência de 14 dias, a partir dos 21 dias após a emergência (DAE) até o florescimento pleno da cultura, obtendo-se o diâmetro de caule e a altura de dossel das plantas. Também foram realizadas três coletas destrutivas aos 35, 70 e 100 DAE para obtenção de massa seca nos diferentes órgãos da planta e área foliar. Na colheita avaliaram-se os componentes da produção, produtividade e acamamento. O retardante vegetal e as densidades de semeadura influenciaram diretamente na altura e no diâmetro de caule das plantas. Para massa seca, componentes da produção, produtividade e acamamento não houve influência, no entanto a área foliar foi influenciada pela densidade de semeadura

Made available in DSpace on 2017-07-10T17:37:26Z (GMT). No. of bitstreams: 1 Leandro_Motter.pdf: 340239 bytes, checksum: 7a4ff6b13fd8e15d79ab1a6a3cd7bceb (MD5) Previous issue date: 2007-08-31 / The wheat that's a culture of high risk, due environmental conditions and weather, and another factors like pests, diseases and fallen plant index. This latter is responsible for losses considerable of grains, since that difficulty a good deal the harvest, occur loss of yield. Thus, the present work if considers to evaluate the effect of the vegetal retardant trinexapac-ethyl, on reduction of the postage of the wheat CD 104, in an attempt to minimize problems caused at fallen plant index related on the manure spreading nitrogen on cover, as well as access the growth and productivity in response the nitrogen and on the application of vegetal retardants. The experiment was developed Experimental Station from COPACOL in the city of Cafelândia - PR. The experimental design was he of blocks at random, in factorial outline (2X6X6), being two levels of nitrogen on cover (40 and 80 kg ha-1) treatments gotten for the combination of six levels of the vegetal retardant 0.0; 0.2; 0.4; 0.6; 0.8; and 1.0 L ha-1) and six collection of plants [20, 35, 50, 65, 80 and 95 days after the emergence (DAE)], with four repetitions. During the conduct after 20 DAE, plans were collected for each 14 days about to ends of biometric analysis and growth. Each one was realized in a randomized way taking plants in 0,30 m in the tillage line, inside from parcel useful in each experimental parcel. In the harvest the components of the yield had been evaluated, productivity and fallen plant index. Trinexapac-ethyl reduces the height of plants and no influence the productivity of the wheat CD 104, but it showed - if effective into the control of fallen plant index, reducing possible losses on harvest. The levels of N applied on cover presented values positive into the increase from productivity of the wheat, by highlighting - if the use of 80 kg ha-1 / O trigo é uma cultura de alto risco, devido às condições ambientais e a incidência de outros fatores como pragas, doenças e acamamento. Este último é responsável por perdas consideráveis de grãos, uma vez que dificulta muito a colheita, ocorrendo perda de produção e qualidade do produto colhido. Dessa forma, o presente trabalho procura demonstrar o efeito do regulador vegetal Etil-trinexapac na redução do porte do trigo CD 104, na tentativa de minimizar problemas causados pelo acamamento relacionados à adubação nitrogenada em cobertura, bem como avaliar o crescimento e produtividade em resposta ao nitrogênio e à aplicação deste regulador vegetal. O experimento foi desenvolvido na Estação Experimental da Cooperativa Agrícola Consolata LTDA COPACOL no município de Cafelândia PR. O delineamento experimental utilizado foi o de blocos ao acaso em esquema fatorial (2x6x6), sendo duas doses de nitrogênio em cobertura (40 e 80 kg ha-1) aplicado aos 35 dias após emergência (DAE), seis concentrações de Etil-trinexapac, aplicado via pulverização (0,0; 0,2; 0,4; 0,6; 0,8 e 1,0 L ha-1) e seis coletas de plantas [20, 35, 50, 65, 80 e 95 dias após a emergência (DAE)], com quatro repetições. Durante a condução do experimento, a partir de 20 DAE, foram realizadas coletas de plantas a cada 14 dias para fins de análise biométrica e de crescimento. Cada coleta foi realizada retirando-se as plantas contidas em 0,30 m na linha de semeadura, de forma aleatória, dentro da parcela útil, em cada parcela experimental. Na colheita avaliaram-se os componentes da produção, produtividade e índice de acamamento. O Etil-trinexapac reduziu a altura de plantas e não influenciou a produtividade do trigo cultivar CD 104, porém mostrou-se efetivo no controle do acamamento, reduzindo possíveis perdas na colheita. As doses de N aplicados em cobertura apresentaram valores positivos no incremento da produtividade do trigo, destacando-se o uso de 80 kg ha-1

<p>Brominated flame retardants (BFRs) are a diverse group of chemicals, which are used to slow down or inhibit the development of fires. BFRs are incorporated into a wide range of consumer products that are considered as potential fire hazards, such as TV-sets, household appliances, computers, and textiles. The production and use of BFRs is extensive and consists of mainly tetrabromobisphenol A (TBBPA), polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecan (HBCD). BFRs in general, but in particular the PBDEs, have led to both scientific and public concern since they have been found to bioaccumulate in humans and wildlife. The general population is targeted by the PBDEs due to their applications and via the food web. Occupational exposure occurs not only during direct handling of BFRs, but also during handling, repair and dismantling of flame retarded goods.</p><p>This thesis is aimed to assess occupational exposure to BFRs. It is mainly focused PBDEs and especially the PBDEs with high bromine content, such as decabromodiphenyl ether (BDE-209). The work has been accomplished by analysis of BFRs in indoor air at industries handling BFRs or flame retarded goods, and by analysis of blood drawn from workers with potential exposure to BFRs. A referent group, abattoir workers with no occupational exposure to PBDEs, was also investigated. Data from these cross-sectional investigations and from serum sampling during vacation in PBDE-exposed workers have been used for calculation of apparent halflives of hepta- to decaBDE in serum.</p><p>The results clearly show that the workers were exposed to PBDEs when handling PBDE containing products or goods. The serum PBDE levels in computer technicians were found to correlate to the estimated cumulative work hours with computers. Exceptionally high concentrations of BDE-209, almost up to 300 pmol/g lipid weight (l.w.) were observed in serum from rubber workers manufacturing or handling rubber compound that was flame retarded with a technical mixture of decabromodiphenyl ether (DecaBDE). Elevated concentrations of PBDEs with eight or nine bromine substituents were also observed. In an electronics dismantling plant, where elevated levels of PBDEs previously had been observed, reduced serum levels of some, but not all PBDE congeners were observed after industrial hygiene improvements. Notably, it was observed that the BDE-209 concentrations in referents with no occupational exposure were similar to the concentrations of 2,2’,4,4’- tetrabromodiphenyl ether (BDE-47), often referred to as the most abundant PBDE congener in humans and wildlife. Additionally, PBDEs with high bromine content were found to have a fast rate of elimination or transformation in humans, based on serum analysis. BDE-209 had an apparent half-life in serum of only 15 days.</p><p>The possibility of quantifying BFRs, such as PBDEs, in human serum at low levels of detection has been achieved by reducing the contamination of the samples and procedural blanks. Major efforts have been done to develop routines and clean up methodology to enable an almost contamination-free environment at the laboratory. The use of a clean room has decreased PBDE levels in the blanks to acceptable limits. The modifications of the original analytical method have made it possible to quantify almost all PBDE congeners of interest in one GC/MS run.</p><p>Occupational and general background exposure of BFRs to humans will continue as long as these chemicals are a part of our daily life and present as environmental contaminants. The present scientific knowledge of the potential health risks of these BFRs still needs to be further developed. It should be stressed that health effects to PBDEs have not been assessed in this work. It is the author's wish that this thesis should add another piece of knowledge to the puzzle of BFRs and BFR exposure to humans and that these data will be used in future risk assessments of PBDEs in particular.</p>