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Tesis sobre el tema "Flame retardants"

Autor: Grafiati
Publicado: 4 de junio de 2021
Última modificación: 25 de julio de 2024

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1

Cequier, Manciñeiras Enrique. "Identifying human exposure pathways to flame retardants". Doctoral thesis, Universitat Rovira i Virgili, 2014. http://hdl.handle.net/10803/283285.

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El principal objetiu d'aquesta tesi consisteix en millorar la comprensió de com i en quina mesura els retardants de flama (RF), tant els heretats com els emergents, que estan incorporats en articles d'ús diari i materials de construcció, entren en els éssers humans. Per això, un grup de 48 mares i els seus fills/es (6-12 anys), residents a l'área metropolitana d'Oslo (Noruega), van participar en l'estudi. Es van recollir mostres biològiques, de sang (només de les mares) i orina, i mostres de pols i aire de l'interior de les viviendes. Per a la determinació de RF persistents en sang es va desenvolupar un mètode basat en GC-MS i un segon mètode, basat en UPLC-TOF, per a la determinació de metabòlits dels RFs excretats en l'orina. Els principals RF persistents detectats en sang van ser: anti-Dechlorane Plus (0.85 ng/g lípid) > BDE -153 (0.82 ng/g lípid) > BDE -47 (0.49 ng/g lípid) > syn-Dechlorane Plus (0.45 ng/g lípid). La suma dels RF emergents va resultar en concentracions comparables a la suma dels difenil èters polibromats, essent els productes alimentaris una de las fonts més importants de RF en aquest estudi. Els dos principals metabòlits detectats en l'orina dels fills/es i les mares van ser el difenil fosfat (1 ng/ml) i el bis(1,3-dicloro-2-propil) fosfat (0.2-0.3 ng/ml). Es va trobar una estreta relació entre les concentracions d'aquests dos metabòlits en l'orina dels fills/es i les concentracions dels RF a l'aire i la pols de las vivendes. Aquest descobriment suggereix que l'ambient interior influeix més significativament en els nivells d'organofosfats en els fills/es que altres fonts com podrien ser els productes alimentaris.
El objetivo principal de esta tesis consiste en mejorar la comprensión de cómo y en qué medida los retardantes de llama (FR), tanto los heredados como los emergentes, que están incorporados en los artículos de uso diario y materiales de construcción, entran en los seres humanos. Para ello, un grupo de 48 madres y sus hijos/as (6-12 años), resididentes en el área metropolitana de Oslo (Noruega), participaron en el estudio. Se recogieron muestras biológicas de sangre (sólo de las madres) y orina, y muestras de polvo y aire del interior de las viviendas. Para la determinación de FR persistentes en sangre se desarrollló un método basado en GC-MS y un segundo método basado en UPLC-TOF para la determinación de metabolitos de los FRs excretados en la orina. Los principales FR persistentes detectados en sangre fueron: anti-Dechlorane Plus (0.85 ng/g lípido) > BDE -153 (0.82 ng/g lípido) > BDE -47 (0.49 ng/g lípido) > syn-Dechlorane Plus (0.45 ng/g lípido). La suma de los FR emergentes resultó en concentraciones comparables a la suma de los difenil éteres polibromados, siendo los productos alimentarios una de las fuentes más importantes de FR en este estudio. Los dos principales metabolitos detectados en la orina de los hijos/as y las madres fueron difenil fosfato (1 ng/ml) y bis(1,3-dicloro-2-propil) fosfato (0.2-0.3 ng/ml). Se encontró una estrecha relación entre las concentraciones de estos dos metabolitos en la orina de los niños y las concentraciones de los FR en el aire y el polvo de las viviendas. Este hallazgo sugiere que el ambiente interior contribuye de manera más significativa en los niveles de organofosfatos en los hijos/as que otras fuentes, como podrían ser los productos alimentarios.
The main research goal of this thesis is to further understanding of how and to what extent flame retardant (FR) chemicals, both legacy and emerging, which are present in every-day consumer goods and construction materials enter in humans. To do so, a cohort of 48 mothers and their offspring (6-12 years) were recruited in the greater area of Oslo (Norway) and samples of blood (only from the mothers), urine, and samples of indoor dust and air were collected. For the determination of persistent FR in blood a method based on GC-MS was developed, and a second method, based on UPLC-TOF, was also developed for the determination of the non-persistent FR (organophosphates) in urine. The main persistent FRs detected in blood were anti-Dechlorane Plus (0.85 ng/g lipid) > BDE-153 (0.82 ng/g lipid) > BDE-47 (0.49 ng/g lipid) > syn-Dechlorane Plus (0.45 ng/g lipid). The sum of the emerging FRs were found in comparable concentrations to the sum of polybrominated diphenyl ethers, diet being one of the most important sources of FRs in this study group. The two main metabolites detected in urine from children and mothers were diphenyl phosphate (1 ng/mL) and bis(1,3-dichloro-2-propyl) phosphate (0.2-0.3 ng/mL). A strong relationship between the concentrations of these two metabolites in urine and the concentrations of the parent compounds in indoor air and dust for children was found. This finding suggests that the indoor environment contributes more importantly to the body burden of organophosphates in children from the cohort than other sources like diet.
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2

Karlsson, Henrik. "Source inventory of flame retardants in Sweden : Does the release of flame retardants pose any danger to the environment?" Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-420787.

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3

Ruflin, Catherine. "New phosphorus containing flame : retardants for cotton fabrics /". Zürich : ETH, 2006. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=16734.

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4

Coleman, G. V. "Development of novel flame retardants for polyurethane foams". Thesis, University of Salford, 1994. http://usir.salford.ac.uk/14783/.

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In line with current environmental concerns, a non—halogenated, high phosphorus content flame retardant for polyurethane foams is preferred. Cyclic phosphorus compounds have a high percentage of phosphorus and should therefore exhibit good flame retardant activity when incorporated into polyurethane foams. One such group of compounds, known as phospholenes, had previously been successfully synthesised but in poor yields and with only a few derivatives being prepared. This work was concerned with identifying and then optimising synthesis routes to a variety of model phospholene oxide esters, that were proposed to have potential as novel flame retardants. Kinetic and mechanistic studies of the simplest synthesis reaction were also investigated. Once optimisation of both stages of the two stage synthesis were successful in raising the yields from -25% to >90%, a flow reactor was designed and constructed to facilitate production of the model compounds in large quantities (-P 1/2 kg) required and then incorporated into polyurethane foams at a variety of loadings. These flame retarded polyurethane foams were prepared and extensive flammability tests were subsequently performed to fully evaluate the model compounds' performance as flame retardants. The model compounds exhibited favourable flame retardant properties, but their physical properties prohibited their use as commercial flame retardants. However the work completed has shown the potential, within this area of compounds, for the commercial development of suitable flame retardants.
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5

Brommer, Sandra. "Characterising human exposure to organophosphate ester flame retardants". Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/5292/.

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Concentrations of selected PFRs were determined in indoor dust from cars, couches, living rooms, offices, and school classrooms in Australia, Canada, Germany, Kazakhstan, and the UK. Significant differences were found between concentrations of PFRs in dust from different microenvironment categories in the same country. Assessment of human exposure via dust ingestion, revealed the majority of exposure to most PFRs occurs in the domestic environment. However, exposure to TDCIPP occurs primarily in cars, and a substantial proportion of the exposure of young children to EHDPP occurs in classrooms. Reassuringly, the exposure estimates in this study are at least 2 orders of magnitude below health based limit values reported in the literature. However, improved characterisation of exposure to TCIPP via inhalation is identified as a research priority. To address the substantial uncertainty in existing values reported for PFR vapour pressures, they were determined experimentally via the GC-RT method. For most target PFRs, results showed good overall agreement with the mean of experimental and \(in\) \(silico\) literature values. However, values for the chlorinated PFRs exceeded the average of literature values.
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6

Priegert, Andrew Mark. "Synthesis, structure, and properties of phosphorus-containing flame retardants". Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/60397.

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7

Biswas, Bhaskar. "Fire retardation of epoxy composites using reactive flame retardants". Thesis, University of Bolton, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.531177.

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8

Wilson, Jonathan Colin. "Further investigation of novel flame retardants for polyurethane foams". Thesis, University of Salford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341311.

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9

Khattab, M. A. A. El-M. M. "Inorganic sulphur oxyacid salts as flame retardants for cotton". Thesis, City University London, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356009.

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10

Durganala, Sravanthi. "Synthesis Of Non-Halogenated Flame Retardants For Polyurethane Foams". University of Dayton / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1312338050.

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11

Liu, Heping. "Substance flow analysis of brominated flame retardants in vehicles". Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263644.

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12

Lindström, Jonna. "Dietary intake estimations of brominated flame retardants for Swedish children". Thesis, Södertörn University College, School of Life Sciences, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-1829.

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The dietary intake of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) have been estimated for Swedish children. A dietary survey performed in 2003, including 4, 8-9 and 11-12 year olds, and concentrations in individual food items were combined. The food included in the study was mainly of animal origin, consisting of fish and shellfish, dairy products, meat products, eggs, animal and vegetable fats and fats from miscellaneous food products. The medium-bound intake of PBDEs (9 congeners) were estimated to 23.0 ng/day, 30.9 ng/day and 27.7 ng/day for 4, 8-9 and 11-12 years olds respectively. The corresponding estimations for HBCD were 7.94 ng/day 10.7 ng/day and 9.46 ng/day for 4, 8-9 and 11-12 years olds respectively. These results show a higher daily intake for 8-9 year olds compared with the other age groups. However, when estimating the daily intake per kg bw, the intake decreases with age. BDE-47 contributed the most to the total intake of PBDEs, with approximately 40%. The food group contributing the most to the intake of PBDEs and HBCD was fish and shellfish, of which non-Baltic fatty fish was the largest contributor. There were no considerable differences between boys and girls in any of the aspects examined. The result from this study show a lower intake of PBDEs and HBCD in Swedish children compared with children in other studies made in Europe and the United States.


Bromerade flamskyddsmedel används för att skydda brännbara material från att fatta eld, till exempel skyddas textilier och plaster i bland annat elektronik, fordon och möbler. Två typer av bromerade flamskyddsmedel är polybromerade difenyletrar (PBDE) och hexabromocyklododekan (HBCD). Dessa är additiva flamskyddsmedel och blandas i materialet som ska skyddas men binder inte in i produkten och kan därför lätt läcka ut i miljön, vilket också har skett. Halter har påträffats i miljön och i biota långt från plaster där ämnena produceras eller används.

PBDE och HBCD har visats ha hormonstörande och neurotoxiska effekter i studier på råtta och mus. Thyroxinnivåerna sjunker vid exponering av PBDE och HBCD, vilket skulle kunna leda till sköldkörtelproblem och störd utveckling av bland annat hjärnan om exponering sker perinatalt. De neurotoxiska effekterna inkluderar inlärnings- och minnessvårigheter och ett förändrat beteende med hyper- och hypoaktivitet som följd.

Human exponering för PBDE och HBCD sker främst via födan och speciellt via animaliska produkter då dessa ämnen är lipofila, bioackumulerande och ofta biomagnifierande vilket gör att de påträffas i högre koncentrationer högre upp i trofinivåerna. Studier från bland annat Sverige och Finland visar att fisk och skaldjur är den största källan till intag av PBDE.

De flesta intagsberäkningar av PBDE och HBCD baseras på livsmedelskonsumtionen hos vuxna och visar följaktligen endast hur intaget ser ut för den delen av populationen. För barn, som är en av de känsligaste grupperna i populationen, finns inte många studier att tillgå, varken från Sverige eller andra delar av världen. I den här studien har därför intaget av PBDE (summan av 9 kongener) och HBCD beräknats för barn i Sverige.

I en rikstäckande kostundersökning utförd 2003 deltog barn i åldrarna 4, 8-9 och 11-12 år. De fick i en matdagbok ange sin konsumtion under fyra på varandra följande dagar. Data från denna undersökning kombinerades sedan med haltdata från olika livsmedel för att räkna ut intaget av PBDE och HBCD på individbasis. Undersökningen innefattade främst animaliska livsmedel och innehöll därför fisk och skaldjur, mejeriprodukter, köttprodukter, ägg, animaliskt och vegetabiliskt fett och fett från övriga livsmedel.

Resultaten visar att födointaget av PBDE var 23,0 ng/dag, 30,9 ng/dag och 27,7 ng/dag för 4, 8-9 respektive 11-12 åringar. Intaget av HBCD beräknades till 7,94 ng/dag, 10,7 ng/dag och 9,46 ng/dag för 4, 8-9 respektive 11-12 åringar. Detta visar att 8-9 åringar har det högsta dagliga intaget av PBDE och HBCD. När intaget beräknas på kroppsvikt däremot, har de yngsta barnen det högsta intaget som sedan sjunker med åldern. Fisk och skaldjur var den största källan till intaget av PBDE och HBCD, trots att konsumtionen av dessa livsmedel var relativt lågt. Det fanns ingen större skillnad mellan pojkar och flickor, varken i intag av PBDE eller av HBCD. Jämfört med de få studier som gjorts i andra länder, är det tydligt att svenska barn har ett lägre intag av PBDE och HBCD.

Undersökningen tyder också på att intaget av PBDE och HBCD hos svenska barn, utifrån de kunskaper vi har idag, inte utgör någon risk med avseende på de effekter av PBDE och HBCD som påträffats i toxikologiska studier. Däremot är barn i ett känsligt skede i livet och upprepad exponering samt exponering för flera miljögifter samtidigt skulle kunna påverka deras utveckling negativt.

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13

Liagkouridis, Ioannis. "Indoor emissions and fate of flame retardants : A modelling approach". Doctoral thesis, Stockholms universitet, Institutionen för miljövetenskap och analytisk kemi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-127258.

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A significant number of consumer goods and building materials act as emission sources of flame retardants (FRs) in the indoor environment. As a result, FRs have become ubiquitous indoors raising concerns about human exposure and possible health implications. Once released indoors, FRs can escape to the outdoors where they can persist, be transported over long distances and present a threat to the environment. Despite the increasing number of studies reporting the occurrence of FRs in the indoor environment, the understanding of i) how and to what extent these chemicals are released from indoor sources, and ii) their subsequent fate indoors remains limited. The overarching objective of this thesis was to improve this understanding by assessing the indoor emissions and fate of FRs using a combination of multimedia modelling strategies and experimental/empirical approaches. Paper I identifies a number of knowledge gaps and limitations regarding indoor emissions and fate of FRs and the available modelling approaches. These include a limited understanding of the key emission mechanisms for low volatility FRs, uncertainties regarding indoor air/surface partitioning, poor characterization of dust and film dynamics and a significant lack of knowledge regarding indoor reaction/degradation processes. In Paper II we highlighted the serious scarcity in physicochemical property data for the alternative FRs and demonstrated the applicability of a simple QSPR technique for selecting reliable property estimates for chemical assessments. A modelling fate assessment indicated a strong partitioning to indoor surfaces and dust for most of the alternative FRs. Indications for POP (persistent organic pollutant)-like persistence and LRT (long-range transport) and bioaccumulative potential in the outdoor environment were also identified for many alternative FRs. Using an inverse modelling approach in Paper III we estimated 2 to 3 orders of magnitude higher emissions of organophosphate FRs (0.52 and 0.32 ng.h-1) than brominated FRs (0.083 μg.h-1 and 0.41 μg.h-1) in Norwegian households. An emission-to-dust signal was also identified for organophosphate FRs suggesting that direct migration to dust may be a key fate process indoors. No evidence of a direct source-to-dust transfer mechanism was seen in Paper IV where the chemical transfer between a product treated with an organophosphate FR and dust in direct contact was experimentally investigated. It was concluded though that direct contact between an FR source and dust can result in contamination hotspots indoors.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.

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14

Battig, Alexander Philipp [Verfasser]. "Hyperbranched Polymers: Multifunctional Flame Retardants for Epoxy Resins / Alexander Battig". Berlin : Freie Universität Berlin, 2020. http://d-nb.info/1218077646/34.

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15

Rattfelt, Nyholm Jenny. "Persistency, bioaccumulation and toxicity assessment of selected brominated flame retardants". Doctoral thesis, Umeå : Department of Chemistry, Umeå University, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-22528.

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16

Battig, Alexander [Verfasser]. "Hyperbranched Polymers: Multifunctional Flame Retardants for Epoxy Resins / Alexander Battig". Berlin : Freie Universität Berlin, 2020. http://d-nb.info/1218077646/34.

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17

Gad, A. M. M. "Metal chelates as flame retardants and photostabilisers for some vinyl polymers". Thesis, City University London, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356010.

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18

Wilford, Bryony Hannah. "Sources, transfers and human exposure to polybrominated diphenyl ether flame retardants". Thesis, Lancaster University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443516.

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19

Kuang, Jiangmeng. "Brominated flame retardants in indoor environments, with a focus on kitchens". Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7769/.

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Paired kitchen-living room dust samples from 30 UK houses were collected for the analysis of BFRs, including PBDEs, HBCDDs and PBEB, EH-TBB, BTBPE, BEH-TEBP, DBDPE. Ninety-six plastic kitchen utensils were collected, screened for Br concentration by X-ray fluorescence spectrometer, with 30 of these samples analysed for BFR concentrations. A simulated cooking experiment was conducted to evaluate BFR exposure. Temporal and geographical differences in concentrations of BFRs in indoor dust samples were investigated via comparing BFR concentrations in UK samples in 2006-07 and 2015 and comparing 116 indoor house dust samples collected between 2014-15 from 6 countries (Finland, Greece, Spain, Jordan, US and Mexico) respectively. Concentrations of BDE-209 in living room dust were significantly lower and those of DBDPE significantly higher (p < 0.05) compared to concentrations in 2006-07 in UK dust. All target BFRs were present at higher concentrations in living rooms than kitchens. Considerable BFR transfer from kitchen utensils to cooking oils was observed and estimated exposure via cooking was 60 ng/day. US dust showed the highest Penta-BDE concentrations, followed by Mexico. Jordanian dust samples contained the highest concentrations of Octa-BDE. US and Mexican samples were found to display a similar composition to that found in the FireMaster® 550 formulation (EH-TBB:BEH-TEBP=4:1).
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20

Moth, Penelope Anne. "The additives as flame retardants and smoke suppressants for polyester thermosets". Thesis, Kingston University, 1992. http://eprints.kingston.ac.uk/20563/.

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The use of tin oxide, zinc stannate and zinc hydroxystannate as flame retardants and smoke suppressants in both halogenated and nonhalogenated polyester resin thermosets has been investigated. Oxygen Index studies showed that zinc stannate in conjunction with the resin based on dibromoneopentyl glycol (DBNPG) was the most efficient combination. This was also the case when the same resin containing less bromine was used (10% instead of 28.3%). It was however the tin oxide which caused the greatest decrease in smoke production. Nitrous Oxide Index tests showed the tetrabromophthalic anhydride (TBPA) and chlorendic anhydride (HET) resins to burn via a vapour phase mechanism and the DBNPG resin to burn via a condensed phase mechanism. Thermogravimetry indicated that the tin oxide did not interact with any of the resins, the additive being recovered almost quantitatively after degradation in air. The Zn/Sn additives interacted with the DBNPG resin with additive being almost completely lost every time. Some interaction was observed with the HET and TBPA resins but this was to a much lesser extent. XRD results indicated the possible formation of tin bromide from a DBNPG sample containing zinc hydroxystannate and this finding would support the theory of a condensed phase mechanism for the DBNPG resin. The SEM photographs indicated the formation of allne powdery layer on the surface of the burnt sample. Elemental analysis by. SEM showed that this contained both zinc and tin, as did the smoke. Residue analysis gave some indication of the temperature at which metal and halogen were volatilised from each sample. The results suggested that for the DBNPG resin with the Zn/Sn additives, it is very likely that tin bromide could be formed as both the tin and bromine are lost in the same temperature ranges. The same could be said for the TBPA resin but to a much lesser extent but for the HET resin it is unlikely that tin chloride could be formed as the volatilisation temperatures do not coincide. In conclusion, a condensed phase mechanism is proposed for the DBNPG resin with the Zn/Sn additives incorporated. It is suggested that this involves the formation of tin bromide which is then hydrolysed in the flame to yield tin oxide and hydrogen halide which can then act as a radical trap and suppress the flame reactions.
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21

Bin, Sulayman Abdulhamid. "Novel Amine-Functionalized Phosphoryl Hydrazine Flame Retardants for Epoxy Resin Systems". University of Dayton / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=dayton154456772870177.

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22

POMA, GIULIA. "Evaluation of bioaccumulation processes of brominated flame retardants in biotic matrices". Doctoral thesis, Università degli Studi di Milano-Bicocca, 2014. http://hdl.handle.net/10281/50902.

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The global reduction in the use of PBDEs and HBCD as flame retardants has opened the way for the introduction of “Novel” BFRs (NBFRs) in place of the banned formulations, indicating those BFRs that are new in the market or newly/recently observed in the environment in respect to PBDEs and HBCD. Consequently, consumption and production of these NBFRs will keep rising, and increasing environmental levels of these chemicals are expected in the near future. Important representatives of this group are decabromodiphenyl ethane (DBDPE), 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), hexabromobenzene (HBB), and pentabromoethylbenzene (PBEB). In Italy, previous studies have shown that some BFRs (PBDEs) were measured at high concentrations in the Varese province due to the presence of a great number of textile and plastic industries, and particularly in the sediments of Lake Maggiore, where those facilities wastewaters are finally collected mainly through two lake tributaries (Bardello and Boesio). For these reasons, the present thesis has the aim to evaluate the presence, and the potential bioaccumulation and biomagnification processes of six different classes of BFRs (PBDEs, HBCD, DBDPE, BTBPE, HBB and PBEB) in the Lake Maggiore ecosystem, with particular regard to zebra mussels (Dreissena polymorpha), zooplankton, one littoral fish species (common roach - Rutilus rutilus), and two different pelagic species (twaite shad – Alosa agone and European whitefish – Coregonus lavaretus). Finally, the study has also considered the BFR contamination in the lake sediments with the aim of characterizing in detail the possible presence of temporal trends and/or identifying potential sources of contamination. Moreover, it is plausible that the BFR uptake by benthic organisms, followed by fish predation, might be a significant source of bioaccumulation.
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23

Alhaji, Faroq Abdullahi. "Studies on the influence of flame retardants and temperature on cellulose pyrolysis in air". Thesis, University of Salford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280869.

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24

Söderström, Gunilla. "On the combustion and photolytic degradation products of some brominated flame retardants". Doctoral thesis, Umeå University, Chemistry, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-107.

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Many modern products, especially electronic goods, are protected by brominated flame retardants (BFR). Some of the most common flame retardants are polybrominated diphenylethers (PBDE), tetrabromobisphenol-A (TBBP-A) and hexabromocyclododecane (HBCD). These compounds have been found in environmental samples and shown to have physiological effects on experimental animals. This thesis considers end-of-life aspects of brominated flame retardants. When spread in the environment, these compounds may be degraded into other forms. For example, if sludge contaminated with PBDE is used as an agricultural fertilizer, the PBDE could be degraded by sunlight to species of PBDE with lower degree of bromination and, to some extent, also form polybrominated dibenzofurans (PBDF). In addition, PBDF and polybrominated dibenzo-p-dioxins (PBDD) are formed during combustion of brominated flame retardants. When waste products with brominated flame retardants are co-combusted with household waste or other chlorinated fuel, polybrominated- chlorinated dibenzo-p-dioxins (PBCDD) and polybrominated- chlorinated dibenzofurans (PBCDF)will be formed. The bromin/chlorine composition of dioxins and furans is dependent on the bromine/chlorine ratio in the fuel, but the types of brominated flame retardants that are being combusted is less important. In the studies reported here, bromine levels higher than "normal" for household waste has been used. The results show that there is a pronounced increase in total dioxin levels in fluegas when when bromine is present, implying that waste containing brominated flame retardants should only be incinerated at combustion plants with effecient air pollution control devices.

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25

Barnes, Otho. "LEACHING POTENTIAL OF METALS AND BROMINATED FLAME RETARDANTS IN OBSOLETE NOTEBOOK COMPUTERS". MSSTATE, 2009. http://sun.library.msstate.edu/ETD-db/theses/available/etd-06242009-160001/.

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Due to the increasing use of electronic components and the accelerated rate in which these components become obsolete, there has been a dramatic increase of discarded electronic waste (E-waste). E-waste includes obsolete electronic products such as computers, scanners, cellular phones, etc. These electronic components are manufactured using a variety of hazardous materials. As these components are discarded, the toxic and hazardous substances may become mobile and could impact human health and the environment. The toxic substances of concern contained in E-waste include heavy metals and brominated flame retardants (BFRs). This study attempts to identify the leaching potential of BFRs and metals.
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26

Mathews, Marc Christopher. "Durable and Non-Toxic Topical Flame Retardants for Cotton and Cotton Blends". NCSU, 2007. http://www.lib.ncsu.edu/theses/available/etd-03222007-125255/.

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Flame retardant chemicals were used as topical finishes on cotton and cotton blended fabric. Comparison of flame resistance and durability of non-bromine/non-antimony flame retardants were explored based on flame resistance testing and physical testing results. Three 100% cotton fabrics and 3 cotton blended fabrics were used. Twenty one different commercially available flame retardants were used as topical finishes on all fabric types. Fabrics were treated and tested at 0, 5, 10 and 25 washes. Final results show that two of the phosphorus flame retardants were durable to 25 washes. Physical testing results show that there were undesirable side effects from the two durable topical treatments. The two phosphorus based flame retardants outperformed the bromine/antimony flame retardants and the non-treated samples in flame resistance.
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27

Söderström, Gunilla. "On the combustion and photolytic degradation products of some brominated flame retardants /". Umeå : Univ, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-107.

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28

Viberg, Henrik. "Neonatal Developmental Neurotoxicity of Brominated Flame Retardants, the Polybrominated Diphenyl Ethers (PBDEs)". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4576.

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29

Thuresson, Kaj. "Occupational exposure to brominated flame retardants : With emphasis on polybrominated diphenyl ethers". Doctoral thesis, Stockholm : Department of Environmental Chemistry, Univ, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-318.

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30

Grant, J. "Ferrocene containing smoke suppressants and flame retardants for semi rigid polyvinyl chloride". Thesis, Northumbria University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317038.

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31

Hörsing, Maritha. "Leaching and Transformation of Flame Retardants and Plasticizers under Simulated Landfill Conditions". Doctoral thesis, Linköpings universitet, Tema vatten i natur och samhälle, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-15204.

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Many products used in our everyday life contain chemicals added to give them specific properties. Flame retardants (FRs) are added to prevent or retard fires in textiles, plastics etc., while plasticizers are supplied to make plastics more flexible. Through their widespread applications chemicals from both groups are emitted and spread in the environment during usage and disposal. For a long time these products were mainly disposed of in landfills, and in many areas they still are. Thus, since some of these chemicals also pose potential environmental risks and health hazards, there is a need to elucidate their fates during exposure to the landfill environmentThe objectives of this thesis were to investigate the leaching and transformation of FRs and plasticizers from products in which they are used under simulated landfill conditions. To assess the importance of changes in these processes as landfills progress through recognised ageing phases (accompanied by large transitions in both physico-chemical and biological conditions) it was desirable to simulate the changes that typically occur in landfills within a short time period, of 1-2 years.. This was achieved using the newly developed intermediate-scale (3 litre) Modular Environmental Test System (METS).The METS were employed in two studies. The first was an investigation of the leaching and degradation of plasticizers from PVC carpet material incubated at different temperatures (20, 37, 55 and 70°C) prevailing in landfills. Plasticizers subjected to this investigation were the phthalates di-2-ethylhexyl phthalate (DEHP) and benzyl-butyl phthalate (BBP), both of which were found to leach from the carpet. The leaching of DEHP and BBP generally increased with increases in the incubation temperature. However, the most rapid leaching of BBP occurred at 37°C, probably due to high microbial activity at this temperature. Both DEHP and BBP were shown to be degraded within the landfill environment and the degradation potential was highest during the methanogenic landfill phase. In the second METS study the leaching of FRs used in both reactive and additive applications (i.e. chemically bonded to and merely blended with the material, respectively) was characterised. The epoxy oligomer tetrabromobishpenol A (TBBPA) and the phosphorus-based Pyrovatex FRs were selected as representatives for the reactive FRs, while the nitrogen-based melamine and phosphorus-based Proban FRs were selected to represent additive classes. During the incubations, which lasted more than two years, the leaching from melamine was shown to be affected by the landfill phase development. The leaching from the Pyrovatex-treated material and the TBBPA epoxy oligomer seemed to result almost entirely from the washout of unreacted manufacturing residuals. This was also probably true for the FR in the Proban-treated material, although it is durable (despite being additively applied) and thus seemed to leach more slowly (manifested as an increase in phosphate levels in the leachate towards the end of the monitoring period).Finally, due to the paucity of knowledge regarding the fate of ether derivatives of TBBPA (which are also used as FRs) an anaerobic degradation assay was performed. The method employed for this assay was a modified, small-scale ISO standard method. In order to evaluate the degradation assay a uniform analytical protocol was developed. The degradation survey showed that losses of TBBPA, TBBPA-dimethyl ether and bisphenol A dimethyl ether occurred, but no losses of the most hydrophobic compound, TBBPA-dibromopropyl ether, were observed.
Många av de varor och produkter vi kommer i kontakt med dagligen innehåller kemikalier, som tillsats för att materialen i produkterna skall få specifika egenskaper. Till dessa sk funktionella kemiska föreningar hör till exempel flamskyddsmedel och mjukgörare. Den förra förhindrar att produkter fattar eld eller minskar omfattningen av brand. Mjukgörare ingår fr a i plaster för att dessa skall bli smidiga och formbara. Eftersom stora mängder av dessa substanser används eller har använts i produkter i samhället har de spridits till många miljöer. Produkterna hamnar ofta på soptipp, då de inte används mer eller är utnötta. Eftersom flera av dessa substanser innebär risk för hälsa och miljö, är det påkallat att utreda hur de beter sig i soptippsmiljön.Syftet med detta avhandlingsarbete är att undersöka eventuell frisättning och omvandling av dessa två typer av funktionella kemikalier i deponimiljö. Sedan tidigare vet man att sådan frisättning kan var starkt kopplad till åldern och därmed utvecklingen av den kemiska och fysiska miljön förändrats fr a genom tillväxten av mikroorganismer i soptippen. För att komma åt att studera frisättningen under de för deponier karakteristiska utvecklingsfaserna utvecklades en metod (Modualr Environmetal Test System; METS) för att simulera faserna över relativt kort tid (ca 1-2 år). I avhandlingen presenteras två studier, där METS utnyttjats: 1) Frisättning av mjukgörare från en PVC-matta i relation till temperaturer, som uppträder i soptippar (20-70oC) samt 2) Läckage av olika flamskyddsmedel i reaktiv respektive additiv användning studerades för olika applikationer. Vid reaktive applikation är flamskyddsmedlet kovalent bundet till polymeren i produktmaterialet, medan det additivt använda flamskyddsmedlet är inblandat i materialet.Två ftalater (di-2-etylhexyl ftalat, DEHP och bensyl-butyl ftalat (BBP), visade sig läcka från mattan, vilket ökade med högre temperature. De frisattes dock som mest vid 37oC, vilket sannolikt beror på den höga mikrobiella aktiviteten vid denna temperatur. Båda ftalterna bröts ned i soptippsmiljön och hastigheten var störst i den metanogena fasen.En epoxyoligomer (tetrabromobishpenol A TBBPA) och Pyrovatex, som bygger på en fosforförening, användes som modeller för reaktiva flamskyddsmedel. Melamin, som klassas som ett kvävebaserat flamskyddsmedel, fick tillsammans med Proban (fosforbaserat) represen-tera de som används additivt. Medan en frisättning av melamin kunde relateras till utvecklingen av deponimiljön simulerad i METS, så verkar den observerade frisättningen av kemikalierna från de reaktivt behandlade Pyrovatexmaterialet och från epoxipolymeren TBBPA förr ha en fysikalisk-kemisk grund oberoende av utvecklingsfaserna i tippmodel-lerna. Flamskyddsmedlen tvättades helt enkelt ut ur de behandlade produkterna. Probanbehandlingen, som motstår förhållandevis många tvättar trots att det används additivt, visade sig läcka långsamt utan en direkt koppling till fasutvecklingen i METS.Kunskaperna om vad som händer med TBBPA:s eterderivat i deponier är i stort sett obefintliga. Flera av dessa derivat används också som flamskyddsmedel. Därför genomfördes en anaerob nedbrytningsstudie av dessa substanser. För att kunna göra denna studie behövdes en omfattande anpassning och utveckling av metodik, vilket resulterade i ett nytt protokoll för analys av dessa ämnen i olika matriser. Studien visade minskning av koncentrationerna av TBBPA, TBBPA-dimetyleter och bisfenol A dimetyl eter, vilket kan tas som ett tecken på att en transformation och/eller nedbrytning skett. Då dessa föreningar kan omvandlas till mer toxiska substanser bör de undersökas vidare.
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32

Lin, Joseph C. (Joseph Chris) 1981. "Determining the removal effectiveness of flame retardants from drinking water treatment processes". Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/29411.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2004.
Includes bibliographical references (p. 52-55).
Low concentrations of xenobiotic chemicals have recently become a concern in the surface water environment. The concern expands to drinking water treatment processes, and whether or not they remove these chemicals while going through the treatment plant. In this study, the concentrations of organophosphoric acid triester flame retardants tributyl phosphate, tri(2-chloroethyl) phosphate, and ethanol, 2-butoxy-, phosphate (3:1) were measured after major treatment processes at the Chattahoochee Drinking Water Plant in Atlanta, Georgia, USA. The findings indicated significant removal of all three organophosphate triesters after the pre-treatment chemical addition of sodium hypochlorite. The interaction of sodium hypochlorite and organophosphate triesters, through oxidation, was suspected to be the reason for the removal. Second, the concentrations of tri(2-chloroethyl) phosphate after the filtration stage and at the clearwell were much greater than values after the sedimentation stage, and were well above the concentration measured at the intake. Exposure to the chemicals within the treatment plant was the chief potential reason for the heightened concentrations.
by Joseph C. Lin.
M.Eng.
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33

Menard, Raphaël. "Synthèse de retardateurs de flamme phosphorés biosourcés pour résines époxy Synthesis of biobased phosphate flame retardants Synthesis of biobased phosphorus-containing flame retardants for epoxy thermosets Comparison of additive and reactive approaches From bio-based phosphorus-containing epoxy monomer to fully bio-based flame-retarded thermosets Synthesis of new flame-retardants by radical chain transfer copolymerization of glycidyl methacrylate and dimethoxy-phosphorylmethyl methacrylate". Thesis, Montpellier, Ecole nationale supérieure de chimie, 2015. http://www.theses.fr/2015ENCM0013.

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La toxicité avérée et le caractère bio-accumulatif des retardateurs de flamme halogénés usuels (PBDE) ont entrainé la mise en place de restrictions d'usage au sein de l'union européenne (REACH). Les retardateurs de flamme phosphorés (RFP) se sont imposés comme alternatives aux solutions halogénées pour leur moindre toxicité et leurs propriétés ignifugeantes adaptées à la composition chimique des résines époxy. Avec l'essor des résines époxy biosourcées, la dépendance aux ressources fossiles pour la synthèse des additifs en tout genre qui entre dans leur composition est devenue problématique. Ainsi, ces travaux s'inscrivent dans une dynamique de développement durable à travers la valorisation d'un composé biosourcé représentatif des structures phénoliques disponibles: le phloroglucinol. La fonctionnalisation directe du phloroglucinol par des groupements phosphates a permis de réaliser une première série d'additifs RFP biosourcés présentant une action ignifugeante prononcée en phase condensée qui réduit le pouvoir calorifique des matériaux ignifugés. A l'échelle macroscopique, une forte intumescence entraîne une décomposition partielle du matériau ignifugé par effet barrière du résidu formé. Cependant, ces additifs réduisent fortement les températures de transitions vitreuse et mécanique par plastification du réseau thermodurcissable. La fonctionnalisation en deux étapes du phloroglucinol a conduit à deux RFP biosourcés additif (P3SP) et réactif (P2EP1SP) de structures comparables. Nous avons ainsi pu mettre en évidence l'intérêt de l'approche réactive qui, en plus de garantir la durabilité des propriétés des matériaux ignifugés, permet une meilleure action en phase condensée qui entraîne une plus forte intumescence. L'approche réactive semblant plus performante, nous avons poursuivi avec la synthèse d'un dernier RFP biosourcé réactif (P2EP1P) dont la structure a été adaptée pour réduire l'effet plastifiant du groupement phosphoré. Enfin, l'étude de différents matériaux 100 % biosourcés contenant le RFP P2EP1P a montré que les inconvénients de l'approche réactive dus à la faible fonctionnalité du RFP réactif peuvent en partie être compensés par l'incorporation d'un co-précurseur époxy de haute fonctionnalité ou d'un agent de réticulation biosourcé aromatique
The toxicity and the bioaccumumulative character of the usual halogenated flame retardants(RFX) lead to uses restrictions of the main FRX (PBDE) in the EU as REACH. The phosphorus-containing flame retardants (FRP) are suitable for the epoxy thermoset because of their action on the hydroxyl groups. Moreover, the FRP are less toxic than the FRX. With the rise of the biobased epoxy thermosets, the dependence on fossil fuels for the additives synthesis has become problematic. Thus, these works are designed in a sustainable development approach through the valorization of a biobased compound which is representative of the biobased phenolic structures. The directe functionalization of the phloroglucinol with phosphate functions has achieved a first generation of biobased additives FRP which exhibit a significant action in the condensed phase and reduce the heat released during the thermal degradation of the fire retarded thermosets. This effect results in a strong intumescence at macroscopic scale and the expanded residue acts as a barrier and leads to a partial degradation of the thermoset. However, these additives plasticize the thermoset network and reduce the glass and the mechanical transition temperatures. A two-steps functionalization of the phloroglucinol leads to two new biobased FRP, an additive (P3SP) and a reactive (P2EP1SP), with similar chemical structures. We were able to highlight the benefit of the reactive approach which favors the condensed phase action and the intumescence. Moreover, the reactive approach ensures the durability of the flame retarded thermoset properties. Since the reactive approach seems more efficient than the additive one, an other reactive FRP was synthesized, whose the structure was optimized to reduce the plasticizing effect of the phosphorus-containing group. Finally, the study of different 100% biobased phosphorus-containing thermosets highlighted that the disadvantages of the reactive approach may be balanced by the incorporation of a high functionality epoxy precursor or an aromatic curing agent
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34

Sipahioglu, Melike Bengu. "Effects Of Nanoadditives And Different Conventional Flame Retardants On The Flammability Of Polystyrene". Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614395/index.pdf.

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In this thesis, there were four purposes. The first one was to investigate effects of nanoclays (NC) on the flammability behavior of polystyrene (PS). The second purpose was to investigate contribution of nanoclays to the flame retardancy performance of conventional phosphorus based flame retardant
triphenyl phosphate (TPP) and its synergist melamine cyanurate (MCA). For the third purpose contribution of nanoclays to the flame retardancy performance of another conventional halogenated flame retardant
brominated epoxy polymer (BE) and its synergist antimony trioxide (AO) was investigated. As the fourth purpose, effects of another nanoadditive
carbon nanotubes (CNTs) on the flammability behavior of PS with and without BE-AO flame retardant system was investigated. Materials were prepared via &ldquo
solution mixing&rdquo
method, while test specimens were shaped by compression and injection molding. Flammability behaviors were investigated by Mass Loss Cone Calorimeter (MLC), Limiting Oxygen Index (LOI) and UL-94 Vertical Burning tests. Other characterization techniques required in this thesis were
X-ray diffraction analyses, scanning and transmission electron microscopy, thermogravimetric analyses and tensile tests. It was revealed that use of nanoclays improved flame retardancy of PS significantly, mainly with &ldquo
condensed phase&rdquo
mechanism via formation of strong char barrier layers inhibiting mass and heat transfer. When nanoclays were used together with conventional flame retardant systems TPP-MCA and BE-AO, flame retardancy parameters improved further, this time due to the &ldquo
synergistic action&rdquo
of &ldquo
condensed phase mechanism&rdquo
of nanoclays and &ldquo
gas phase mechanism&rdquo
of the conventional systems. Use of carbon nanotubes also resulted in improvements in the flame retardancy of PS. However, &ldquo
condensed phase mechanism&rdquo
of CNTs were not as effective as the NCs, which might be due to the lower performance of 1D geometry (CNTs) compared to higher efficiency of 2D geometry (NC) in barrier formation. As an additional purpose, effects of mixing methods in the production of PS-Nanoclay composites were also investigated. It was seen that compared to &ldquo
solution mixing&rdquo
use of &ldquo
in-situ polymerization&rdquo
resulted in poorer flame retardancy parameters that might basically be due to residual monomers or oligomers left during polymerization.
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35

Julander, Anneli. "Exposure to brominated flame retardants in electronics recycling : air and human plasma levels /". Örebro : Örebro universitetsbibliotek, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-91.

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36

Molefe, Dan Matlhomola. "Magnesium hydroxide derivatives as stabilisers and flame retardants for plasticised poly (vinyl chloride)". Thesis, University of Pretoria, 2015. http://hdl.handle.net/2263/53529.

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The potential of magnesium hydroxide, hydromagnesite and layered double hydroxides (LDHs) as heat stabilisers and flame retardants for plasticised poly (vinylchloride) (PVC) was studied. These inorganic hydrated fillers feature flake-shaped particles with a strong tendency to agglomerate. Filler particles must be homogeneously distributed and individually dispersed in the polymer matrix in order to attain the best performance. For this reason the first step in the investigation was to explore the use of a stearic acid coating in order to improve the dispersability of these fillers in liquids. The platelet morphology-type flame retardants were coated with approximately a monolayer of stearic acid using a solvent technique. Compared to the uncoated powders, the BET surface area was lower, the powder packing density was improved, and the thickening effect on white oil was significantly reduced. The latter two observations were rationalised in terms of a reduction in the attractive interactions between the powder particles. The viscosity of white oil slurries containing 25 wt.% solids showed shear-thinning non-Newtonian behaviour. The coated powders showed significantly lower viscosities at low shear rates although the difference diminished at high shear rates. The lower viscosities shown by the coated powders indicate that the surface modification facilitated the break-up of agglomerates and aided the dispersion of individual particles in the fluid. The thermal decomposition of these hydrated fillers is central to their flame retardant action. At elevated temperatures they endothermically release inert gases. The latter dilute the atmosphere surrounding the burning sample while the endothermic decomposition cools the substrate. These two effects are responsible for the flame retardant action of these fillers. The detailed behaviour of the present samples was studied using thermogravimetric analysis and spectroscopic methods. The decomposition mechanisms, proposed in the literature for these flame retardants, were confirmed. This includes the mass loss, enthalpy of decomposition, and the nature of evolved gases for temperatures up to 1 000 °C. The magnesium hydroxide decomposed endothermically at temperatures well above 250 °C releasing only steam. The LDH decomposed between 225 ºC and 450 ºC and the hydromagnesite between about 220 °C and 500 °C. Both initially released water vapour followed by carbon dioxide. Next the utility of the magnesium hydroxide, hydromagnesite and LDH as combination heat stabilisers and flame retardants for plasticised PVC was studied. Emulsion grade PVC was plasticised with 100 parts per hundred parts of resin (phr) diisononyl phthalate (DINP) and filled with 30 parts per hundred parts of resin (phr) filler additive. Thermomat static heat stabilities were determined at 200 °C by following the time dependence of hydrogen chloride evolution. Fire retardancy was studied using a cone calorimeter at a radiant flux of 35 kW m-2. The layered double hydroxide outperformed the other fillers with regard to improving heat stabilisation and also with respect to most fire retardancy indices. Since the layered double hydroxide performed best it was decided to see whether slight composition variations could improve performance. Derivatives of the standard LDH compound ([Mg0.667Al0.333(OH)2](CO3)0.167·0.44H2O) were synthesised using a hydrothermal method. Again, emulsion grade PVC was plasticised with 100 phr diisononyl phthalate and stabilised with 30 phr of the LDH filler additive derivatives. The heat stability and fire resistance of these compounds were studied. Heat stabilities were determined at 200 °C. The dynamic heat stability tests were performed on the plastisols using the torque rheometer method. Static heat stability was evaluated on the fused compounds. It was evaluated from discoloration profiles of strips exposed for various lengths of time to high heat in a Metrastat oven. The time dependence of hydrogen chloride evolution was followed with a Metrohm Thermomat instrument. The conventional LDH provided the best dynamic heat stability. However, partial replacement of the magnesium with copper significantly delayed the release of volatile HCl. If instead the replacement was done using zinc, better colour retention was achieved. The fire performance was determined at a radiant flux of 35 kWm?2 in a cone calorimeter. The conventional magnesium-aluminium LDH lowered the peak heat release rate of the plasticised PVC from 623 ± 8 kW m?2 to 389 ± 9 kW m?2 and reduced the smoke release by 37 %. Partial replacement of the aluminium with iron resulted in a red pigmented additive that was more effective as a flame retardant reducing the peak heat release rate (pHRR) to as little as 253 ± 5 kW m?2. This additive also showed better smoke suppression (reduction of 44 %) but the best smoke suppression was achieved by replacing part of the magnesium with copper reduction by 49 %).
Thesis (PhD)--University of Pretoria, 2015.
Chemistry
PhD
Unrestricted
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37

Pereira, Lílian Cristina. "Alterações mitocondriais induzidas por representantes das principais classes de Éteres Difenílicos Polibromados". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/60/60134/tde-28062012-101506/.

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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.
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38

Merilis, Giorvanni. "Distribution of Polybrominated Diphenyl Ethers Among Demographic Categories". Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6903.

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Polybrominated Diphenyl Ethers (PBDEs) are flame retardants widely used within the United States in various products such as plastics, electronics, textiles and furniture. With an increase in production and usage, PBDEs have recently emerged as a contaminant of concern. Due to their chemical structure, PBDEs have the propensity to bioaccumulate in mammals. In fact, elevated PBDE concentrations have been recorded in human breast milk. Due to the potential widespread exposure to PBDEs, this study investigates human blood concentrations of PBDEs generated through the 2003-2004 National Health and Nutrition Examination Survey. Through the use of statistical modeling, a comparison of mean PBDE concentrations in ng/g lipid is conducted based on age, gender and ethnicity. From a sample of 2337 individuals, the average blood concentration of PBDEs was approximately 81 ng/g lipid. The average PBDE concentration of males was significantly higher than females, using a 95% confidence level. In addition, PBDEs detected in human blood ranged approximately from 0.05 to 3676 ng/g lipid, with the highest concentrations found in black males. Also, a logistic regression analysis is conducted to determine whether an increase in background PBDE concentrations is a risk factor for obesity. Furthermore, the analyses of PBDEs are repeated for phthalates and polychlorinated Biphenyls for comparison. Finally, the measured concentrations of PBDEs are also compared to health outcome data known to show potential risk.
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39

Cristale, Joyce. "Priority and emerging flame retardants in the aquatic environment: analytical development, occurrence and risk". Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/127637.

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The presence of priority and emerging flame retardants (FR) in the environment deserve attention since many of these substances are toxic and persistent. The aim of this thesis was to evaluate the occurrence and impact of priority and emerging flame retardants in the aquatic environment. To accomplish this main objective, the present thesis involved the development of multiresidue methods for the analysis of different FR families in water, sediment, dust and sewage sludge and the application of developed methods for FR monitoring in rivers (UK and Spain) and wastewater treatment plants (WWTPs). Firstly, a multiresidue method based on gas chromatography (GC) coupled to quadrupole mass spectrometry (MS) was developed to determine organophosphorus flame retardants (OPFRs), polybrominated diphenyl ethers (PBDEs), new brominated flame retardants (NBFRs), bromophenols, bromoanilines, bromoanisoles and bromotoluenes. A comparison of two ionization techniques (electron ionization - EI, and electron capture negative ionization - ECNI) and two acquisition modes (selected ion monitoring – SIM, and selected reaction monitoring - SRM) revealed that GC-ECNI-MS/SIM presented the highest sensitivity at expenses of identification capacity, while GC-EI-MS/MS was the most selective technique, permitting the identification of target compounds at the pg levels. This last method was proposed for the determination of FRs in environmental samples. An extraction method for 8 PBDEs, 9 NBFRs and 10 OPFRs in river water and wastewater was developed based on solid phase extraction using Oasis HLB cartridges. In addition, a passive sampling method for monitoring of OPFRs and NBFRs in surface water was developed using the ceramic dosimeter device with HLB as receiving phase. The passive sampler was efficient for the monitoring of target compounds in river water for a deployment time of about 3 weeks, as evidenced by comparison of results obtained by passive and grab sampling. Furthermore, the extraction of target compounds in sediment, sewage sludge and dust was developed using ultrasound-assisted extraction with ethyl acetate/cyclohexane (5:2, v/v), clean-up with florisil cartridges and analysis by GC-EI-MS/MS. The method proved to be efficient and robust for analysis of target compounds in the studied matrices, as evidenced by the results obtained using spiked samples, a certificated reference material and by participating in an interlaboratory study. Monitoring studies were performed at the River Aire (Yorkshire, UK) and at three Spanish rivers (Nalón, Arga and Besòs). In all cases, samples were collected in several points alongthe rivers, fromthe sourceto the mouth, and afterWWTP outputs, in order to identify themost important sourcesof FRs. In addition, influents, effluentsand sludge samples from five Spanish WWTPs were analyzed forevaluatingthe impact of WWTPs as a source ofFRto receiving waters. Among all FR studied, OPFRswerethe most ubiquitouscontaminants in surface waters, andWWTPeffluents wereindicated as the main source ofthese compounds.BDE-209 was themost abundantPBDEcongenerand was detected in water inthe River Aire (UK),in sediments fromthe River Besòs (Catalonia)and in sewage sludge.Low frequency of detection wasobserved for NBFRs in the studied riversand WWTPs.The minor presence of NBFR in the aquaticenvironment pointsto the impression thateither thesecompounds havenotbeen used in Spain or the UK or eitherthatthey have not been used long enough or atsufficient amounts to pose an environmental problem.A toxicity testperformed with Daphniamagnarevealed that OPFRs toxicity (EC50) waswell correlated with their lipophilicity (log Kow), that these compoundspresent similar mode of actionand thattheir joint effects are additive.This mean that joint toxicity of OPFRs at lowconcentrations can produce toxic effects in theaquatic organisms,andsomixturesof these contaminantsmust be considered in risk assessmentstudies. Finally, theriskassessment performed for the studied rivers indicated no risk associated to observedOPFR levels in waters. However, apotential risk foraquatic organismswas estimatedfor the River Aire (UK) associated tothehigh concentrationsof BDE-209 in water.
El objetivo de la presente tesis consistió en el desarrollo de métodos para el análisis multiresiduo de distintas familias de retardantes de llama en matrices ambientales, y su aplicación en estudios de vigilancia ambiental. Entre los diferentes métodos instrumentales desarrollados, el método basado en la cromatografía de gases acoplada a la espectrometría de masas en modo tándem (GC-EI-MS/MS) fue el más adecuado para el análisis de ocho éteres de polibromodifenilo (PBDEs), nueve nuevos retardantes de llama bromados (NBFRs) y diez retardantes de llama organofosforados (OPFRs) en las matrices ambientales propuestas en este estudio. Para el análisis de agua, se desarrolló un método basado en la extracción en fase sólida utilizando cartuchos HLB. Además, se desarrolló un método de muestreo pasivo para la determinación de cuatro OPFRs y dos NBFRs en agua de río utilizando un muestreador “ceramic dosimeter” y HLB como fase receptora. Para el análisis de sedimentos, lodos de depuradora y polvo, se desarrolló y validó un método utilizando la extracción líquido-sólido en un baño de ultrasonidos con acetato de etilo/ciclohexano (5:2, v/v), y purificación de los extractos con cartuchos florisil. El estudio de vigilancia ambiental incluyó la determinación de los compuestos objeto de estudio en 4 ríos de Inglaterra y España y cinco depuradoras en Catalunya. Se analizaron aguas y sedimentos de los ríos e influentes, efluentes y lodos de las depuradoras. Se observó que los OPFRs son los compuestos más ubicuos y más abundantes en todas las muestra ambientales, mientras el BDE-209 se detectó en los ríos y en los lodos de las depuradoras. Los demás PBDEs, y el DBDPE, HBB, PBEB, PBT, EHTBB, BTBPE y BEHTBP se detectaron con una menor frecuencia. Los estudios de toxicidad con Daphnia magna indicaron que mezclas de OPFRs poseen toxicidad aditiva. Se llevó a cabo la evaluación del riesgo para los distintos ríos estudiados y se observó que no hay un riesgo asociado con los niveles de los OPFRs presente en las aguas, pero se observó un riesgo asociado a la presencia del BDE-209 en las aguas del río Aire en Inglaterra.
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40

Andresen, Jens Arne. "Emission, fate and behaviour of phosphororganic flame retardants and plasticisers in the aquatic environment". [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=979245125.

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41

Duberg, Daniel. "Identification of volatile organic compounds (VOC) and organophosphate flame retardants (OPFR) in building materials". Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-64604.

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Humans today spend most of their time in various indoor settings such as housing, schools and workplaces. The quality of the indoor environment is therefore of great significance for our wellbeing. However, it has been suggested that the indoor environment contains over 6000 organic compounds, such as various volatile organic compounds (VOC). Around 500 of these compounds is believed to be due to emissions from different surrounding building materials such as insulation, plastic film, sealants and flooring. This study targeted building materials from three low energy preschools that were sampled and analyzed for emissions of VOCs and nine different organophosphate flame retardant compounds (OPFR) using a gas chromatograph coupled to a mass spectrometer (GC/MS). Low energy buildings are buildings that is particularly air tight to be so energy efficient as possible. The study uses a qualitative approach and therefore mainly identifies possible contribution from building materials to indoor environment. More than 100 different VOCs was identified and the most noticeable were meta-, ortho- and para-xylene, toluene, n-hexane and propylene glycol, all but the last compound is associated with hazardous health effects. The building materials that emitted the largest amounts of VOCs was sealants and adhesives. Linoleum flooring and acrylic was also large emitters. Tris(1-chloro-2-propyl) phosphate (TCIPP) were identified in all samples and all nine targeted OPFR compounds were identified in the various material samples and dust samples. T-Flex tape and plastic film was the sample materials that emitted most OPFR compounds.
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42

Marklund, Anneli. "Levels and sources of organophosphorus flame retardants and plasticizers in indoor and outdoor environments". Doctoral thesis, Umeå : Dept. of Chemistry, Environmental Chemistry, Univ, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-640.

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43

Karlsson, Marie. "Levels of brominated flame retardants in humans and their environment : occupational and home exposure /". Örebro : Örebro universitetsbibliotek, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-694.

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44

Björklund, Justina. "Brominated flame retardants and perfluoroalkyl acids in Swedish indoor microenvironments : Implications for human exposure". Doctoral thesis, Stockholms universitet, Institutionen för tillämpad miljövetenskap (ITM), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-63701.

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Humans are exposed to persistent organic pollutants (POPs) such as brominated flame retardants (BFRs, specifically polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD)) and perfluoroalkyl acids (PFAAs, specifically perfluoroalkane sulfonate (PFOS) and perfluorooctanoic acid (PFOA)). They are used in consumer products found in cars, offices, homes and day care centers. Diet was earlier thought to be a major human exposure route for legacy POPs, but does not account for body burdens found for many new POPs and indoor exposure from air and dust has been hypothesized as also important. In this thesis, BFRs in air and dust, and PFAAs in dust from different indoor microenvironments in Sweden were analysed, and the results used to estimate human exposure. BFRs and PFAAs were detected in dust from all microenvironments and PBDEs in all air samples. BFR and PFAA exposure occurs mostly in peoples’ homes with toddlers having higher intakes from dust ingestion than adults. Inhalation and dust ingestion play minor roles compared to diet for humans with median exposures, but in worst case scenarios, dust ingestion may be significant for a small part of the Swedish population. Sampling using home vacuum cleaner bag dust and researcher-collected above floor dust was compared. Correlations were seen for ∑OctaBDE and ∑DecaBDE but not for ∑PentaBDE and HBCD. Higher PBDE concentrations were found in above floor dust but higher HBCD concentrations were found in vacuum cleaner bag dust. BDE-47 concentrations were correlated between vacuum cleaner bag dust and breast milk, indicating exposure through dust ingestion. Similar concentrations of PBDEs were measured in indoor and outgoing air from day care centers, apartment and office buildings. Indoor air explained 54-92% of ∑PentaBDE and 24-86% of BDE-209 total emissions to outdoor air in Sweden, supporting the hypothesis that the indoor environment is polluting ambient air via ventilation systems.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Accepted. Paper 3: Accepted. Paper 4: Manuscript.

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45

Devine, Stephen John. "The Production of Nano-Sized Particulate Flame Retardants and their Application in Thermoplastic Polymers". Thesis, Teesside University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.517589.

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46

Ortiz, Carrizales Yessica Patricia. "Factors influencing human exposure assessment of organophosphorus flame retardants (OPFRS) via indoor dust ingestion". Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8071/.

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Concentrations of selected organophosphate flame retardants (PFRs) were determined in samples of living room dust from differents countries with international differences in absolute concentrations and relative abundance of different PFRs. Other substantial international differences were observed that are likely attributable to variations in flame retardant legislation and use between different countries. Within-room, within-home, and between home temporal and spatial variation in concentrations of PFRs in floor dust and elevated surface dust was studied in 3 homes from Birmingham, UK. Of particular note are the seasonal variations in PFR concentrations where by higher concentrations were observed in spring and summer; and that between-home spatial variation was largely attributable to differences in flooring composition. Moreover, higher concentrations were generally found in elevated surface rather than floor dust. Concentrations of PFRs were determined in indoor air from houses and offices in Birmingham, UK. Finally, controlled chamber experiments were conducted to examine the magnitude and rate of PFR transfer from a treated fabric to dust via direct fabric-dust contact. A key finding was that source-to-dust transfer via direct contact occurs and over the time period of our experiments was proportional to the duration of contact; with the majority of PFRs, transfer from fabric to dust via direct contact occurs within the first 4 days of contact.
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47

Tao, Fang. "Aspect human exposure to emerging and legacy flame retardants in the UK and Vietnam". Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6925/.

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Analytical methods based on gas chromatography in combination with electron capture negative ion/electron ionisation mass spectrometry were developed and validated for the separation and determination of legacy and emerging flame retardants (EFRs) in a wide range of samples including indoor air, dust, diet and human milk. A broad suite of EFRs and legacy flame retardants (FRs) including polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCDDs) were determined in indoor air and dust taken from offices and homes in Birmingham, UK. Comparison with previous data, suggests that temporal trends in contamination with EFRs and legacy FRs reflect changes in production and use of such compounds as a result of bans and restrictions on the use of legacy FRs. Using inter alia a simple, single compartment, steady state pharmacokinetic model, human exposure to FRs via air inhalation, dust ingestion and diet was estimated for different age groups and the relative importance of each exposure route to overall exposure assessed under different exposure scenarios. Concentrations of target EFRs were detected for the first time in UK human milk samples (n=35). Human exposure to EFRs and HBCDDs via diet was estimated for a population impacted by a rudimentary e-waste processing area in Vietnam.
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48

Guzzonato, Antonella. "An evaluation of instrumental tools to screen for the presence of brominated flame retardants". Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8464/.

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In this study a number of analytical techniques for the screening, quantification and identification of brominated flame retardants in consumers’ products, electric and electronic waste and indoor dust is explored. The presented work can be conceptually divided in two parts: - The first explores, evaluates and pushes the limits of solid sampling techniques (i.e. X-Ray Fluorescence and Laser Ablation Inductively Coupled Plasma Mass Spectrometry) as a tool for the total elemental quantification of Bromine and its use as a metric for BFR content in consumers’ goods and waste. The XRF method proved to be accurate to 94% (relative to LA-ICP-MS results), making the technique (used with the developed calibration) reliable for the quantification of Br in polymers. REEs concentrations obtained with LA-ICP-MS were used to evaluate the origin of contaminants in FCAs and toys. - The second part explores the suitability of solid sampling techniques (that do not require sample preparation) and simplified liquid sampling techniques (that require sample preparation in the form of solvent assisted extraction) for the compound specific, semi quantitative evaluation of BFRs in plastic material and indoor dust. DIP-HRMS and DART-HRAM showed sufficient linearity over the calibration range and mass determination accurate enough to unequivocally identify BDE209 in polymeric matrices. GC-ICP-MS analysis performed with ad-hoc developed hardware provided reliable data for the semi-quantitative evaluation of indoor dust PBDE profile.
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49

Chen, Da. "Polybrominated diphenyl ether flame retardants in birds of prey from the U.S. and China". W&M ScholarWorks, 2009. http://www.vims.edu/library/Theses/Chen09.pdf.

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50

WU, YAN. "EXPOSURE OF NORTH AMERICAN AQUATIC AND TERRESTRIAL ECOSYSTEMS TO LEGACY AND EMERGING FLAME RETARDANTS". OpenSIUC, 2018. https://opensiuc.lib.siu.edu/dissertations/1564.

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Flame retardants (FRs) represent a set of widely used industrial chemicals that are added to consumer products (e.g. electronics, plastics, and textiles), to reduce their flammability if exposed to a small flame. FRs, particularly halogenated ones, have been extensively detected in a variety of environmental compartments and biological samples worldwide, which raised significant concerns during the past decades due to their persistent, bioaccumulative and toxic potentials. Several in vivo and epidemiological studies have confirmed that FRs may interfere with neurodevelopment and endocrine systems. Therefore, the most intensively utilized group of halogenated FRs, polybrominated diphenyl ethers (PBDEs), was withdrawn from the market during 2004 – 2013. Consequently, an increase in demand for other emerging FRs was expected. Due to the phase-out of PBDEs, decreasing or plateauing trends in their concentrations have been observed in a few North American environmental matrices. However, research on emerging FRs remains limited in both terrestrial and aquatic ecosystems. In response to these knowledge gaps and research needs, my dissertation research evaluated the exposure of selected North American aquatic and terrestrial ecosystems to legacy and emerging FRs, including PBDEs, hexabromocyclododecane isomers (HBCDs), Dechlorane analogues (Dechloranes), and alternative brominated FRs (ABFRs, other non-PBDE brominated FRs). After a general introduction to contamination status of selected FRs as well as their adverse effects on test animals, ecosystems, and public health (Chapter I), the aquatic systems I investigated included the Great Lakes (Chapter II) and the San Francisco Bay (Chapter III), representing an important freshwater and estuarine ecosystem, respectively. Peregrine falcon (Falco peregrinus) eggs collected from various regions in the U.S. and Canada were analyzed to address spatial and temporal distributions of FRs in the North American terrestrial ecosystems (Chapter IV). In Chapter II, I investigated the occurrence and spatiotemporal distribution of selected FRs in the Great Lakes fish mega-composite collected from 2004 – 2016. Following the phase-out of PBDE and HBCD FRs in the North American market, the use of alternative FRs has increased. In this study the occurrence and spatiotemporal distributions of 17 Dechlorane analogues and 21 brominated FRs in Great Lakes top predator fish mega-composites was investigated. Frequently detected FRs in samples collected from 2004 to 2016 include Dechlorane (Dec) 602, 603, 604 Component B, anti-Dechlorane plus (DP), syn-DP, and Chlordene Plus, as well as several brominated benzene FRs (i.e., hexabromobenzene, pentabromotoluene, and tetrabromo-o-chlorotoluene). Concentrations of ΣDechloranes (including all Dechlorane analogues) and ΣABFRs (including all alternative brominated FRs) ranged from 0.33 – 31.9 ng/g lipid weight or lw (0.01 – 8.3 ng/g wet weight or ww) and 0.91 – 54.7 ng/g lw (0.09 – 7.1 ng/g ww), respectively. Their levels were generally one to two orders of magnitude lower than PBDEs. Flame retardant contamination exhibited chemical-specific spatial variations across the five lakes. Concentrations of ΣABFRs in Lake Erie fish were generally lower than those from other lakes. By contrast, fish concentrations and compositions of Dechloranes differed significantly between Lake Ontario and other lakes, indicating point-source influence. Temporal trend analyses revealed declining trends in ΣDechloranes and ΣABFRs in most lakes except Lake Erie, with trend slopes of -13.45% to -8.83% and -20.06% to -6.97%, respectively. Additional FR chemicals not included in the present study that are on the market and possibly subject to an increasing demand will be the subject of future studies. Continuous efforts are needed to investigate not only the myriad of alternative FRs themselves, but also their main degradation or transformation products. Chapter III presented a wide-ranging characterization of selected FRs in surface sediments and biological samples (i.e., deployed bivalves, sport fish, harbor seal blubber, and cormorant eggs) of a highly urbanized estuary, San Francisco Bay, once considered a hot spot for PBDE contamination. Among the studied FRs, PBDEs were still the most abundant contaminants in all Bay matrices as well. BDE-209 was the predominant PBDE congener in Bay sediments, while BDE-47, -99, and -100 together accounted for greater than 85% of ∑PBDEs in Bay biota. Other FR analytes detected in the Bay ecosystem (i.e., sediments and biota) included HBBZ, TBCT, 1,2-bis(2,4,6-tribromophenoxyl) ethane (BTBPE), Dec-602, Dec-603, CPlus, mono-dechlorinated DP (C11-DP), and syn- and anti-DP. Significantly higher levels of ∑PBDEs, ∑ABFRs, and ∑Dechloranes were observed in South Bay, relative to North Bay, probably due to greater urbanization in South Bay together with its geographical and hydrological features. Biomagnification (BMF > 1.0) via sport fish-harbor seal food chain were observed for BDE-47, -99, -153, TBCT, HBBZ, CPlus, Dec-602, Dec-603, syn- and anti-DP. In Chapter IV, the peregrine falcon eggs in this study were collected from the U.S. (New Jersey, Chesapeake Bay, Pennsylvania, California) and Canada (British Columbia, New Brunswick, Ontario, and Quebec). Similarly, the concentrations of ∑PBDEs (204.7 – 44224.3 ng/g lw) in the peregrine eggs were at least one order magnitude greater than those of ∑HBCDs (5.6 – 2426.4 ng/g lw), ∑Dechloranes (22.1 – 1918.2 ng/g lw), and ∑ABFRs (6.1 – 1181.8 ng/g lw). Several FRs, such as heavier PBDE congeners (octa-, nona-, and deca-BDEs), Dec-604, and 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB), which were not frequently detected in the Great Lakes and the San Francisco Bay organisms, were constantly quantifiable in the peregrine eggs. According to the FR burdens in recently sampled peregrine eggs, higher concentrations of ∑PBDEs and ∑ABFRs were observed in the New Jersey eggs, whereas the Ontario and Quebec eggs possessed greater levels of ∑HBCDs. The concentrations of ∑Dechloranes in peregrine eggs were comparable among the studied regions. The New Jersey, Ontario, and Quebec samples were used to elucidate the FR temporal trends in the peregrine falcon eggs. Temporal trends in concentrations of ∑PBDEs were obscure in the New Jersey and Ontario eggs, while those in Quebec eggs were significantly fitted in a quadratic curve with a breaking point at 1999. Concentrations of ∑HBCDs increased significantly in peregrine eggs from Ontario (1995 – 2015) and Quebec (1984 – 2012), while ∑Dechlorane levels declined in New Jersey and Quebec eggs collected after 1990 and 1998, respectively. No time trends were detected for concentrations of ∑ABFRs in the peregrine eggs from these three regions. In summary, although PBDEs were still the most abundant FRs, introduction of PBDE replacements have resulted in their occurrence in the North American ecosystems. Differences in FR compositional patterns were observed among the Great Lakes fish, the San Francisco Bay organisms and the peregrine falcon eggs, likely due to physiochemical properties of FRs, proximity to FR pollution sources, and human activity influences. Additionally, greater flame-retardant concentrations in organisms at higher trophic levels in the Bay ecosystem indicated their potentials to be biomagnified through the food chain.
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