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Sample records for flame retardant styrene

  1. Preparation of candidate reference materials for the determination of phosphorus containing flame retardants in styrene-based polymers.

    Science.gov (United States)

    Roth, Thomas; Urpi Bertran, Raquel; Latza, Andreas; Andörfer-Lang, Katrin; Hügelschäffer, Claudia; Pöhlein, Manfred; Puchta, Ralph; Placht, Christian; Maid, Harald; Bauer, Walter; van Eldik, Rudi

    2015-04-01

    Candidate reference materials (RM) for the analysis of phosphorus-based flame retardants in styrene-based polymers were prepared using a self-made mini-extruder. Due to legal requirements of the current restriction for the use of certain hazardous substances in electrical and electronic equipment, focus now is placed on phosphorus-based flame retardants instead of the brominated kind. Newly developed analytical methods for the first-mentioned substances also require RMs similar to industrial samples for validation and verification purposes. Hence, the prepared candidate RMs contained resorcinol-bis-(diphenyl phosphate), bisphenol A bis(diphenyl phosphate), triphenyl phosphate and triphenyl phosphine oxide as phosphorus-based flame retardants. Blends of polycarbonate and acrylonitrile-co-butadiene-co-styrene as well as blends of high-impact polystyrene and polyphenylene oxide were chosen as carrier polymers. Homogeneity and thermal stability of the candidate RMs were investigated. Results showed that the candidate RMs were comparable to the available industrial materials. Measurements by ICP/OES, FTIR and NMR confirmed the expected concentrations of the flame retardants and proved that analyte loss and degradation, respectively, was below the uncertainty of measurement during the extrusion process. Thus, the candidate RMs were found to be suitable for laboratory use.

  2. Microwave-assisted synthesis of SiO2 nanoparticles and its application on the flame retardancy of poly styrene and poly carbonate nanocomposites

    Directory of Open Access Journals (Sweden)

    A. Esmaeili-Bafghi-Karimabad

    2015-07-01

    Full Text Available Various morphologies of silica nanoparticles were synthesized by a microwave-assisted Pechini method. Silica nanostructures were synthesized via a fast reaction between tetra ethyl ortho silicate and ammonia at presence citric acid and other effective agents in Pechini procedure. Then for preparation of polymer-matrix nanocomposites, SiO2 nanoparticles were added to poly carbonate (PC and poly styrene (PS matrices. Nanostructures were characterized by X-ray diffraction (XRD, scanning electron microscopy (SEM and Fourier transform infrared (FT-IR. The influence of SiO2 nanostructures on the flame retardancy of the polymeric matrix was studied using UL- 94 analysis. Our results show that the SiO2 nanostructure can enhance the flame retardant property of the poly carbonate matrix. PC shows better flame retardancy compare to poly styrene.

  3. Flame Retardant Epoxy Resins

    Science.gov (United States)

    Thompson, C. M.; Smith, J. G., Jr.; Connell, J. W.; Hergenrother, P. M.; Lyon, R. E.

    2004-01-01

    As part of a program to develop fire resistant exterior composite structures for future subsonic commercial aircraft, flame retardant epoxy resins are under investigation. Epoxies and their curing agents (aromatic diamines) containing phosphorus were synthesized and used to prepare epoxy formulations. Phosphorus was incorporated within the backbone of the epoxy resin and not used as an additive. The resulting cured epoxies were characterized by thermogravimetric analysis, propane torch test, elemental analysis and microscale combustion calorimetry. Several formulations showed excellent flame retardation with phosphorous contents as low as 1.5% by weight. The fracture toughness of plaques of several cured formulations was determined on single-edge notched bend specimens. The chemistry and properties of these new epoxy formulations are discussed.

  4. Neurotoxicity of brominated flame retardants

    Science.gov (United States)

    Polybrominated diphenyl ethers (PBDEs) have been commonly used as commercial flame retardants in a variety of products including plastics and textiles. Despite their decreasing usage worldwide, congeners continue to accumulate in the environment, including soil, dust, food, anima...

  5. Flame Retardants Used in Flexible Polyurethane Foam

    Science.gov (United States)

    The partnership project on flame retardants in furniture seeks to update the health and environmental profiles of flame-retardant chemicals that meet fire safety standards for upholstered consumer products with polyurethane foam

  6. Flame retardant cotton based highloft nonwovens

    Science.gov (United States)

    Flame retardancy has been a serious bottleneck to develop cotton blended very high specific volume bulky High loft fabrics. Alternately, newer approach to produce flame retardant cotton blended High loft fabrics must be employed that retain soft feel characteristics desirable of furnishings. Hence, ...

  7. Nanocellular foam with solid flame retardant

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Liang; Kelly-Rowley, Anne M.; Bunker, Shana P.; Costeux, Stephane

    2017-11-21

    Prepare nanofoam by (a) providing an aqueous solution of a flame retardant dissolved in an aqueous solvent, wherein the flame retardant is a solid at 23.degree. C. and 101 kiloPascals pressure when in neat form; (b) providing a fluid polymer composition selected from a solution of polymer dissolved in a water-miscible solvent or a latex of polymer particles in a continuous aqueous phase; (c) mixing the aqueous solution of flame retardant with the fluid polymer composition to form a mixture; (d) removing water and, if present, solvent from the mixture to produce a polymeric composition having less than 74 weight-percent flame retardant based on total polymeric composition weight; (e) compound the polymeric composition with a matrix polymer to form a matrix polymer composition; and (f) foam the matrix polymer composition into nanofoam having a porosity of at least 60 percent.

  8. Analysis of radiation polymerization of flame retarder

    International Nuclear Information System (INIS)

    Enomoto, Ichiro; Sawai, Takeshi; Ametani, Kazuo

    1990-01-01

    It was found that when vinyl phosphonate oligomer was irradiated with electron beam, the decrease of thermogravity in three steps arose. It was presumed that the first decrease of weight was due to the vaporization of water. This value is nearly constant independent of dose, but when divided irradiation was carried out, as dose increased, the decrease of weight became less. Fire damages have increased as population concentrates into cities and overcrowding occurs. To make combustible materials as well as the textile products belonging to people flame-retardant has become a social problem. The flame retarders and the method of processing which do not generate harmful gas in combustion are demanded. The practical test on making fibers flame-retardant by using radiation graft polymerization has been carried out since 1984, and the method of processing without generating harmful gas was obtained. It is necessary to elucidate the basic property of flame retarders due to irradiation for further developing the technology of flame retardation. This time, the thermogravimetric change of the flame retarders polymerized with radiation was examined. The experimental method and the results are reported. (K.I.)

  9. A, a Brominated Flame Retardant

    Directory of Open Access Journals (Sweden)

    Tomomi Takeshita

    2013-01-01

    Full Text Available Tetrabromobisphenol A (TBBPA, a brominated flame retardant, has been found to exacerbate pneumonia in respiratory syncytial virus- (RSV- infected mice. We examined the effect of Brazilian propolis (AF-08 on the exacerbation of RSV infection by TBBPA exposure in mice. Mice were fed a powdered diet mixed with 1% TBBPA alone, 0.02% AF-08 alone, or 1% TBBPA and 0.02% AF-08 for four weeks and then intranasally infected with RSV. TBBPA exposure increased the pulmonary virus titer and level of IFN-γ, a representative marker of pneumonia due to RSV infection, in the lungs of infected mice without toxicity. AF-08 was significantly effective in reducing the virus titers and IFN-γ level increased by TBBPA exposure. Also, AF-08 significantly reduced proinflammatory cytokine (TNF-α and IL-6 levels in the lungs of RSV-infected mice with TBBPA exposure, but Th2 cytokine (IL-4 and IL-10 levels were not evidently increased. Neither TBBPA exposure nor AF-08 treatment affected the anti-RSV antibody production in RSV-infected mice. In flow cytometry analysis, AF-08 seemed to be effective in reducing the ratio of pulmonary CD8a+ cells in RSV-infected mice with TBBPA exposure. TBBPA and AF-08 did not exhibit anti-RSV activity in vitro. Thus, AF-08 probably ameliorated pneumonia exacerbated by TBBPA exposure in RSV-infected mice by limiting excess cellular immune responses.

  10. Flame retardant cotton barrier nonwovens for mattresses

    Science.gov (United States)

    According to regulation CPSC 16 CFR 1633, every new residential mattress sold in the United States since July 2007 must resist ignition by open flame. An environmentally benign “green”, inexpensive way to meet this regulation is to use a low-cost flame retardant (FR) barrier fabric. In this study, a...

  11. Preparation of Flame Retardant Modified with Titanate for Asphalt Binder

    Directory of Open Access Journals (Sweden)

    Bo Li

    2014-01-01

    Full Text Available Improving the compatibility between flame retardant and asphalt is a difficult task due to the complex nature of the materials. This study explores a low dosage compound flame retardant and seeks to improve the compatibility between flame retardants and asphalt. An orthogonal experiment was designed taking magnesium hydroxide, ammonium polyphosphate, and melamine as factors. The oil absorption and activation index were tested to determine the effect of titanate on the flame retardant additive. The pavement performance test was conducted to evaluate the effect of the flame retardant additive. Oxygen index test was conducted to confirm the effect of flame retardant on flame ability of asphalt binder. The results of this study showed that the new composite flame retardant is more effective in improving the compatibility between flame retardant and asphalt and reducing the limiting oxygen index of asphalt binder tested in this study.

  12. Daphnid life cycle response to new generation of flame retardants

    NARCIS (Netherlands)

    Waaijers, S.L.; Bleyenberg, T.E.; Dits, A; Schoorl, M.; Schütt, J; Kools, S.A.E.; de Voogt, P.; Admiraal, W.; Parsons, J.R.; Kraak, M.H.S.

    2013-01-01

    Relatively hazardous brominated flame retardants (BFRs) are currently substituted with halogen-free flame retardants (HFFRs). Consequently, information on their persistence, bioaccumulation and toxicity (PBT) is urgently needed. Therefore, we investigated the chronic toxicity to the water flea

  13. Effectiveness of Flame Retardants in TufFoam.

    Energy Technology Data Exchange (ETDEWEB)

    Abelow, Alexis Elizabeth [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Nissen, April [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Massey, Lee Taylor [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Whinnery, LeRoy L. [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2017-12-01

    An investigation of polyurethane foam filled with known flame retardant fillers including hydroxides, melamine, phosphate-containing compounds, and melamine phosphates was carried out to produce a low-cost material with high flame retardant efficiency. The impact of flame retardant fillers on the physical properties such a s composite foam density, glass transition temperature, storage modulus, and thermal expansion of composite foams was investigated with the goal of synthesizing a robust rigid foam with excellent flame retardant properties.

  14. Phosphorus flame retardants: Properties, production, environmental occurrence, toxicity and analysis

    NARCIS (Netherlands)

    van der Veen, I.; de Boer, J.

    2012-01-01

    Since the ban on some brominated flame retardants (BFRs), phosphorus flame retardants (PFRs), which were responsible for 20% of the flame retardant (FR) consumption in 2006 in Europe, are often proposed as alternatives for BFRs. PFRs can be divided in three main groups, inorganic, organic and

  15. Preparation and characterizations of flame retardant polyamide 66 fiber

    Science.gov (United States)

    Li, Y. Y.; Liu, K.; Xiao, R.

    2017-06-01

    The polyamide 66 (PA66) is one of the most important thermoplastic materials, but it has the drawback of flammability. So the flame retardant PA66 was prepared by condensation polymerization using nylon salt and DOPO-based flame retardant in this paper. Then the flame retardant PA66 fiber was manufactured via melt spinning. The properties of flame retardant PA66 and flame retardant PA66 fiber were investigated by relative viscosity, differential scanning calorimetry (DSC), tensile test, vertical burning test (UL94) and limiting oxygen index (LOI) test. Although the loading of the DOPO-based flame retardant decreased the molecular weight, the melting temperature, the crystallinity and the mechanical properties of flame retardant PA66, the flame retardancy properties improved. The flame retardant PA66 loaded with 5.5 wt% of DOPO-based flame retardant can achieve a UL94 V-0 rating with a LOI value of 32.9%. The tenacity at break decreased from 4.51 cN·dtex-1 for PA66 fiber to 2.82 cN·dtex-1 for flame retardant PA66 fiber which still satisfied the requirements for fabrics. The flame retardant PA66 fiber expanded the application of PA66 materials which had a broad developing prospect.

  16. Flexible PVC flame retarded with expandable graphite

    CSIR Research Space (South Africa)

    Focke, WW

    2014-02-01

    Full Text Available The utility of expandable graphite as a flame retardant for PVC, plasticized with 60 phr of a phosphate ester, was investigated. Cone calorimeter results, at a radiant flux of 35 kW m 2, revealed that adding only 5 wt.% expandable graphite lowered...

  17. Hormonal activities of new brominated flame retardants

    Czech Academy of Sciences Publication Activity Database

    Ezechiáš, Martin; Svobodová, Kateřina; Cajthaml, Tomáš

    2012-01-01

    Roč. 87, č. 7 (2012), s. 820-824 ISSN 0045-6535 R&D Projects: GA ČR GA104/09/0694 Institutional research plan: CEZ:AV0Z50200510 Keywords : Brominated flame retardants * 2,4,6-Tribromophenol * Endocrine disruptors Subject RIV: EE - Microbiology, Virology Impact factor: 3.137, year: 2012

  18. Brominated flame retardants and endocrine disruption

    NARCIS (Netherlands)

    Vos, J.G.; Becher, G.; Berg, van den M.; Boer, de J.; Leonards, P.E.G.

    2003-01-01

    From an environmental point of view, an increasing important group of organohalogen compounds are the brominated flame retardants (BFRs), which are widely used in polymers and textiles and applied in construction materials, furniture, and electronic equipment. BFRs with the highest production volume

  19. Brominated flame retardants and endocrine disruption

    NARCIS (Netherlands)

    Vos, Joseph G.; Becher, Georg; Van Den Berg, Martin; Leonards, Pim E G

    2003-01-01

    From an environmental point of view, an increasing important group of organo-halogen compounds are the brominated flame retardants (BFRs), which are widely used in polymers and textiles and applied in construction materials, furniture, and electronic equipment. BFRs with the highest production

  20. Flame retardancy and thermal degradation of cotton textiles based on UV-curable flame retardant coatings

    International Nuclear Information System (INIS)

    Xing, Weiyi; Jie, Ganxin; Song, Lei; Hu, Shuang; Lv, Xiaoqi; Wang, Xin; Hu, Yuan

    2011-01-01

    The flame retardant coatings were prepared through UV-curable technique using tri(acryloyloxyethyl) phosphate (TAEP) and triglycidyl isocyanurate acrylate (TGICA). Results from FTIR-ATR spectroscopy and scanning electron microscopy (SEM) showed that flame retardant coatings were successfully coated onto the surface of cotton fabrics. The flame retardancy of the treated fabrics was studied by Micro-scale Combustion Calorimeter (MCC) and limited oxygen index (LOI). The cottons coated flame retardant coatings had the lower peak heat release rate (PHRR), heat release capacity (HRC), total heat of combustion (THC) and higher LOI value compared with untreated cotton. The results from TGA test showed that the flame retardant coatings lowered the decomposition temperature of treated fabric. The thermal decomposition of cottons was monitored by real time FTIR analysis and thermogravimetric analysis/infrared spectrometry (TGA-IR). The enhanced flame retardant action might be caused by thermal decomposition of TAEP structure, producing acidic intermediates, which could react with fabrics to alter its thermal decomposition process.

  1. Recycling of plastic waste: Screening for brominated flame retardants (BFRs).

    Science.gov (United States)

    Pivnenko, K; Granby, K; Eriksson, E; Astrup, T F

    2017-11-01

    Flame retardants are chemicals vital for reducing risks of fire and preventing human casualties and property losses. Due to the abundance, low cost and high performance of bromine, brominated flame retardants (BFRs) have had a significant share of the market for years. Physical stability on the other hand, has resulted in dispersion and accumulation of selected BFRs in the environment and receiving biota. A wide range of plastic products may contain BFRs. This affects the quality of waste plastics as secondary resource: material recycling may potentially reintroduce the BFRs into new plastic product cycles and lead to increased exposure levels, e.g. through use of plastic packaging materials. To provide quantitative and qualitative data on presence of BFRs in plastics, we analysed bromophenols (tetrabromobisphenol A (TBBPA), dibromophenols (2,4- and 2,6-DBP) and 2,4,6-tribromophenol (2,4,6-TBP)), hexabromocyclododecane stereoisomers (α-, β-, and γ-HBCD), as well as selected polybrominated diphenyl ethers (PBDEs) in samples of household waste plastics, virgin and recycled plastics. A considerable number of samples contained BFRs, with highest concentrations associated with acrylonitrile butadiene styrene (ABS, up to 26,000,000ngTBBPA/g) and polystyrene (PS, up to 330,000ng∑HBCD/g). Abundancy in low concentrations of some BFRs in plastic samples suggested either unintended addition in plastic products or degradation of higher molecular weight BFRs. The presence of currently restricted flame retardants (PBDEs and HBCD) identified in the plastic samples illustrates that circular material flows may be contaminated for extended periods. The screening clearly showed a need for improved documentation and monitoring of the presence of BFRs in plastic waste routed to recycling. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Assessing Pediatric Nurses' Knowledge About Chemical Flame Retardants.

    Science.gov (United States)

    Distelhorst, Laura; Bieda, Amy; DiMarco, Marguerite; Tullai-McGuinness, Susan

    Chemical flame retardants are routinely applied to children's products and are harmful to their health. Pediatric nurses are in a key position to provide education to caregivers on methods to decrease their children's exposure to these harmful chemicals. However, a critical barrier is the absence of any program to educate nurses about chemical flame retardants. In order to overcome this barrier, we must first assess their knowledge. This article provides key highlights every pediatric nurse should know about chemical flame retardants and reports the results of a knowledge assessment study. The purpose of this study was to (1) assess pediatric nurses' knowledge of chemical flame retardants, (2) determine what topic areas of chemical flame retardants pediatric nurses lack knowledge in, and (3) determine the best method to educate nurses about chemical flame retardants. A single sample cross-sectional questionnaire design was used. A total sample of 417 advanced practice registered nurses and registered nurses completed an online survey about chemical flame retardants. Pediatric nurses' knowledge of chemical flame retardants was low (M=13.4 out of 51). Articles, webinars, and e-mails were the primary preferred methods for education on the subject identified as a result of the survey. Pediatric nurses have a large knowledge deficit related to chemical flame retardants. The data collected from this study will help structure future educational formats for pediatric nurses on chemical flame retardants to increase their knowledge. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Polysiloxane-Based Organoclay Nanocomposites as Flame Retardants

    Science.gov (United States)

    2013-01-01

    Polysiloxanes INTRODUCTION Halogen -based flame - retardant (FR) polymers and additives have been a cost-effective solution for FR appli- cations. However, there...D ec em be r 20 13 non- halogenated flame retardant polymers. Green Chem. 2011, 13 (3), 659–665. 7. Lewicki, J.P.; Liggat, J.J.; Patel, M. The...blended through several techniques with organoclays Cloisite 30B, 10A and Naþ ranging from 1 to 5 wt.%. Thermal and flame - retardant analysis

  4. Mass spectrometric characterization of halogenated flame retardants.

    Science.gov (United States)

    Guo, Tan; LaBelle, Bruce; Petreas, Myrto; Park, June-Soo

    2013-07-15

    Concerns about the adverse health effects of ubiquitous flame retardants spurred our interest in the development of a sensitive and reliable analytical method for these toxic compounds in various sample matrices. This study focuses on the investigation of fragmentation pathways and the structures of target ions of thirteen new halogenated flame retardants. In this study, we use gas chromatography (GC)/high-resolution double-focusing sector mass spectrometry to characterize the fragmentation pathways of these new flame retardants. Along with the isotope patterns, accurate mass data were acquired to verify the molecular formula. The fragmentation pathways are classified based on the types of bond dissociations, e.g. σ-bond cleavage, α-bond cleavage and multiple-bond dissociations with a hydrogen shift. The α-bond dissociation occurs among 1,2-bis-(2,4,6-tribromophenoxy)ethane, allyl 2,4,6-tribromophenyl ether (ATE), 2,3-dibromopropyl 2,4,6-tribromophenyl ether (DPTE) and 2-bromoallyl 2,4,6-tribromophenyl ether (BATE). The peak clusters that dominated ATE, BATE and hexachlorocyclopentenyl-dibromocyclooctane (HCDBCO) spectra correspond to two fragments as proved by accurate mass data and isotope patterns. These two fragments are formed as the result of two competing fragmentation pathways of radical loss and hydrogen shift. Fragmentation pathways of the other compounds are complex, involving cleavage of multiple bonds and hydrogen shifts. The accurate-mass-based GC/MS method offers great selectivity and sensitivity for quantitative analysis of the persistent organic pollutants. Thus, elucidation of the structures of the fragments is of prime importance for building an accurate-mass-based isotopic method. In addition, this study is useful for GC/MS/MS method development because multiple reaction monitoring (MRM) transitions of precursor ions and product ions may be easily elucidated based on these fragmentation patterns. Copyright © 2013 John Wiley & Sons, Ltd.

  5. Nanotechnology finding its way into flame retardancy

    Energy Technology Data Exchange (ETDEWEB)

    Schartel, Bernhard, E-mail: bernhard.schartel@bam.de [BAM Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12205 Berlin (Germany)

    2014-05-15

    Nanotechnology is one of the key technologies of the 21{sup st} century. The exploitation of 'new' effects that arise from materials structured on the nano-scale has also been proposed successfully for flame retardancy of polymers since the end of the 90s. Of all of the approaches these include, at this time the use of nanocomposites offers the best potential for industrial application, also some other ideas are sketched, such as using electrospun nanofibers mats or layer-by-layer deposits as protection coatings, as well as sub-micrometer multilayer coatings as effective IR-mirrors. The general phenomena, inducing a flow limit in the pyrolysing melt and changing the fire residue, are identified in nanocomposites. Key experiments are performed such as quasi online investigation of the protection layer formation to understand what is going on in detail. The flame retardancy mechanisms are discussed and their impact on fire behaviour quantified. With the latter, the presentation pushes forward the state of the art. For instance, the heat shielding is experimentally quantified for a layered silicate epoxy resin nanocomposite proving that it is the only import mechanism controlling the reduction in peak heat release rate in the investigated system for different irradiations. The flame retardancy performance is assessed comprehensively illuminating not only the strengths but also the weak points of the concepts. Guidelines for materials development are deduced and discussed. Apart from inorganic fillers (layered silicate, boehmite, etc.) not only carbon nanoobjects such as multiwall carbon nanotubes, multilayer graphene and graphene are investigated, but also nanoparticles that are more reactive and harbor the potential for more beneficial interactions with the polymer matrix.

  6. New hybrid halogen-free flame retardants

    Science.gov (United States)

    Kijowska, Dorota; Jankowski, Piotr

    2014-05-01

    The main objective of this work were researches concerning the methods of the in-situ modification of silicate layer-tubular mineral (SL-TM) halloysite, using the salts of melamine, i.e. melamine cyanurate. The modified mineral was used as flame retardant to thermoplastic polymers. In the case of the application of halloysite modified by melamine cyanurate to polyamide 6 (PA6) the highest parameters of vertical and horizontal flammability were achieved. The mechanical properties of filled polyamide 6 have been improved.

  7. Flame retardants: Dust - and not food - might be the risk

    NARCIS (Netherlands)

    de Boer, J.; Ballesteros-Gomez, A.M.; Leslie, H.A.; Brandsma, S.H.; Leonards, P.E.G.

    2016-01-01

    Flame retardants (FRs) are used to delay ignition of materials such as furniture and electric and electronic instruments. Many FRs are persistent and end up in the environment. Environmental studies on flame retardants (FRs) took off in the late 1990s. Polybrominated diphenylethers (PBDEs) appeared

  8. Environmental fate & effects of new generation flame retardants

    NARCIS (Netherlands)

    Waaijers, S.L.

    2014-01-01

    There is a pressing need for substituting several halogenated flame retardants, given the human and environmental health concerns of many of these compounds. Halogen Free Flame Retardants (HFFRs) have been suggested as alternatives and are already being marketed, although their potential impact on

  9. Toxicity of new generation flame retardants to Daphnia magna

    NARCIS (Netherlands)

    Waaijers, S.L.; Hartmann, J; Soeter, A.M.; Helmus, R.; Kools, S.A.E.; de Voogt, P.; Admiraal, W.; Parsons, J.R.; Kraak, M.H.S.

    2013-01-01

    There is a tendency to substitute frequently used, but relatively hazardous brominated flame retardants (BFRs) with halogen-free flame retardants (HFFRs). Consequently, information on the persistence, bioaccumulation and toxicity (PBT) of these HFFRs is urgently needed, but large data gaps and

  10. Flame retardant antibacterial cotton high-loft nonwoven fabrics

    Science.gov (United States)

    Flame retardant treated gray cotton fibers were blended with antibacterial treated gray cotton fibers and polyester/polyester sheath/core bicomponent fibers to form high-loft fabrics. The high flame retardancy (FR) and antibacterial property of these high lofts were evaluated by limiting oxygen inde...

  11. Life cycle assessment of flame retardants in an electronics application

    NARCIS (Netherlands)

    Jonkers, Niels; Krop, Hildo; van Ewijk, Harry; Leonards, Pim E.G.

    2016-01-01

    Purpose: Flame retardants are added to plastics and textiles to save lives. However, certain brominated flame retardants (BFRs) form an environmental hazard and should be replaced by less harmful alternatives. In the recently completed European research project ENFIRO, we examined which alternatives

  12. Flame Retardant Applications in Camping Tents and Potential Exposure.

    Science.gov (United States)

    Keller, Alexander S; Raju, Nikhilesh P; Webster, Thomas F; Stapleton, Heather M

    2014-02-11

    Concern has mounted over health effects caused by exposure to flame retardant additives used in consumer products. Significant research efforts have focused particularly on exposure to polybrominated diphenyl ethers (PBDEs) used in furniture and electronic applications. However, little attention has focused on applications in textiles, particularly textiles meeting a flammability standard known as CPAI-84. In this study, we investigated flame retardant applications in camping tents that met CPAI-84 standards by analyzing 11 samples of tent fabrics for chemical flame retardant additives. Furthermore, we investigated potential exposure by collecting paired samples of tent wipes and hand wipes from 27 individuals after tent setup. Of the 11 fabric samples analyzed, 10 contained flame retardant additives, which included tris(1,3-dichloroisopropyl) phosphate (TDCPP), decabromodiphenyl ether (BDE-209), triphenyl phosphate, and tetrabromobisphenol-A. Flame retardant concentrations were discovered to be as high as 37.5 mg/g (3.8% by weight) in the tent fabric samples, and TDCPP and BDE-209 were the most frequently detected in these samples. We also observed a significant association between TDCPP levels in tent wipes and those in paired hand wipes, suggesting that human contact with the tent fabric material leads to the transfer of the flame retardant to the skin surface and human exposure. These results suggest that direct contact with flame retardant-treated textiles may be a source of exposure. Future studies will be needed to better characterize exposure, including via inhalation and dermal sorption from air.

  13. Halogenated flame retardants in the Great Lakes environment.

    Science.gov (United States)

    Venier, Marta; Salamova, Amina; Hites, Ronald A

    2015-07-21

    Flame retardants are widely used industrial chemicals that are added to polymers, such as polyurethane foam, to prevent them from rapidly burning if exposed to a small flame or a smoldering cigarette. Flame retardants, especially brominated flame retardants, are added to many polymeric products at percent levels and are present in most upholstered furniture and mattresses. Most of these chemicals are so-called "additive" flame retardants and are not chemically bound to the polymer; thus, they migrate from the polymeric materials into the environment and into people. As a result, some of these chemicals have become widespread pollutants, which is a concern given their possible adverse health effects. Perhaps because of their environmental ubiquity, the most heavily used group of brominated flame retardants, the polybrominated diphenyl ethers (PBDEs), was withdrawn from production and use during the 2004-2013 period. This led to an increasing demand for other flame retardants, including other brominated aromatics and organophosphate esters. Although little is known about the use or production volumes of these newer flame retardants, it is evident that some of these chemicals are also becoming pervasive in the environment and in humans. In this Account, we describe our research on the occurrence of halogenated and organophosphate flame retardants in the environment, with a specific focus on the Great Lakes region. This Account starts with a short introduction to the first generation of brominated flame retardants, the polybrominated biphenyls, and then presents our measurements of their replacement, the PBDEs. We summarize our data on PBDE levels in babies, bald eagles, and in air. Once these compounds came off the market, we began to measure several of the newer flame retardants in air collected on the shores of the Great Lakes once every 12 days. These new measurements focus on a tetrabrominated benzoate, a tetrabrominated phthalate, a hexabrominated diphenoxyethane

  14. Development of Flame Retardants for Engineering Polymers and Polyurethanes

    Science.gov (United States)

    Desikan, Anantha

    2013-03-01

    With a broad portfolio of brominated, organophosphorus and inorganic flame retardants, ICL Industrial Products (ICL-IP) is engaged in the development of new flame retardants by exploiting the synergism between bromine based, phosphorus based and other halogen-free flame retardants. ICL-IP is also focusing on the development of polymeric and reactive flame retardants. This presentation will give examples of existing and new polymeric and reactive products for applications in thermoplastics, thermosets and polyurethane foam. This presentation will also show examples of phosphorus-bromine synergism allowing partial or complete elimination of antimony trioxide in many thermoplastics for electronic applications. New synergistic combinations of magnesium hydroxide with phosphorus and other halogen-free FRs will be presented. Work done in collaboration with S. Levchik, ICL-IP America, 430 Saw Mill Rriver Rd., Ardsley, NY, 10502, USA and M. Leifer, ICL-IP, P. O. Box 180, Beer Sheva 84101, Israel.

  15. Aryl Polyphosphonates: Useful Halogen-Free Flame Retardants for Polymers

    Directory of Open Access Journals (Sweden)

    Li Chen

    2010-10-01

    Full Text Available Aryl polyphosphonates (ArPPN have been demonstrated to function in wide applications as flame retardants for different polymer materials, including thermosets, polycarbonate, polyesters and polyamides, particularly due to their satisfactory thermal stability compared to aliphatic flame retardants, and to their desirable flow behavior observed during the processing of polymeric materials. This paper provides a brief overview of the main developments in ArPPN and their derivatives for flame-retarding polymeric materials, primarily based on the authors’ research work and the literature published over the last two decades. The synthetic chemistry of these compounds is discussed along with their thermal stabilities and flame-retardant properties. The possible mechanisms of ArPPN and their derivatives containing hetero elements, which exhibit a synergistic effect with phosphorus, are also discussed.

  16. Persistence, bioaccumulation and toxicity of halogen-free flame retardants.

    NARCIS (Netherlands)

    Waaijers, S.L.; Kong, D; Hendriks, H.S.; de Wit, C.A.; Cousins, I.T.; Westerink, R.H.S.; Leonards, P.E.G.; Kraak, M.H.S.; Admiraal, W.; de Voogt, P.; Parsons, J.R.

    2013-01-01

    Polymers are synthetic organic materials that have a high carbon and hydrogen content, which renders them readily combustible. When used in buildings, electrical appliances, furniture, textiles, transportation, mining, and in many other applications, polymers have to fulfill flame retardancy

  17. Environmental fate & effects of new generation flame retardants

    OpenAIRE

    Waaijers, S.L.

    2014-01-01

    There is a pressing need for substituting several halogenated flame retardants, given the human and environmental health concerns of many of these compounds. Halogen Free Flame Retardants (HFFRs) have been suggested as alternatives and are already being marketed, although their potential impact on the environment cannot be properly assessed because of a lack of information regarding their environmental and ecotoxicological properties. The aim of this study was to determine the aquatic fate an...

  18. Sorption of Organophosphorus Flame Retardants (OPFRs) on ...

    Science.gov (United States)

    Organophosphorus flame retardants (OPFRs) are widely used as additives in industrial and consumer products such as electrical and electronic products, furniture, plastics, textiles, and building/construction materials. Due to human exposure and potential health effects, OPFRs including tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCPP), and tris(1,3-dichloro-2-propyl) phosphate (TDCPP) are EPA Action Plan chemicals for chemical assessments under the Toxic Substances Control Act (TSCA). This work investigated the sorption of these three compounds from the air to settled Arizona Test Dust (ATD) and house dust (HD) in a dual small chamber system. The OPFR exposed dust was analyzed to determine the sorption concentration and sorption rate of OPFRs on the dust. The effect of the composition of the dust on OPFR sorption was evaluated. The results showed that ATD and HD have varied sorption capacity for OPFRs from air. This work explores the relationship between OPFR concentrations in settled dust and air. The data can be used to determine partitioning of OPFRs between the gas phase and settled dust indoors and to inform strategies to reduce exposure and risk.

  19. Simultaneous determination of brominated and phosphate flame retardants in flame-retarded polyester curtains by a novel extraction method.

    Science.gov (United States)

    Miyake, Yuichi; Tokumura, Masahiro; Nakayama, Hayato; Wang, Qi; Amagai, Takashi; Ogo, Sayaka; Kume, Kazunari; Kobayashi, Takeshi; Takasu, Shinji; Ogawa, Kumiko; Kannan, Kurunthachalam

    2017-12-01

    The use of novel brominated flame retardants (BFRs) and phosphate-based flame retardants (PFRs) has increased as substitutes for hexabromocyclododecane (HBCD) in many consumer products. To facilitate collection of data on chemicals used as flame retardants in textiles and fabrics, we developed an analytical method using liquid chromatography interfaced with tandem mass spectrometry (LC-MS/MS). We compared two extraction methods, one involving ultrasonic extraction (traditional method) using dichloromethane, toluene or acetone and the other encompassing complete dissolution of textile with 25% 1,1,1,3,3,3-hexafluoro-2-propanol/chloroform. The dissolution method extracted up to 204 times more BFRs and PFRs than the traditional ultrasonic extraction. Tris(2,3-dibromopropyl) isocyanurate (TDBP-TAZTO), triphenylphosphine oxide (TPhPO), tris(1,3-dichloro-2-propyl) phosphate (TDCPP), tricresyl phosphate (TCsP), and triphenyl phosphate (TPhP) were found in 40 flame-retarded curtain samples purchased from Japanese market in 2014. TDBP-TAZTO was detected in polyester curtains for the first time. Some of the flame-retarded curtain samples did not contain any of the known target analytes, which suggested the presence of other unknown flame retardants in those fabrics. Copyright © 2017. Published by Elsevier B.V.

  20. Development of fiber reactive, non-halogenated flame retardant on cotton fabrics and the enhanced flame retardancy by covalent bonding

    Science.gov (United States)

    The US law requires flame resistant properties on apparel or house hold items to prevent or minimize the fire damage. The objective of this research was to develop a non-halogenated flame retardant for application onto cotton fabrics. These treated fabrics can then be used in clothes or beddings to ...

  1. Exposure to flame retardant chemicals on commercial airplanes.

    Science.gov (United States)

    Allen, Joseph G; Stapleton, Heather M; Vallarino, Jose; McNeely, Eileen; McClean, Michael D; Harrad, Stuart J; Rauert, Cassandra B; Spengler, John D

    2013-02-16

    Flame retardant chemicals are used in materials on airplanes to slow the propagation of fire. These chemicals migrate from their source products and can be found in the dust of airplanes, creating the potential for exposure. To characterize exposure to flame retardant chemicals in airplane dust, we collected dust samples from locations inside 19 commercial airplanes parked overnight at airport gates. In addition, hand-wipe samples were also collected from 9 flight attendants and 1 passenger who had just taken a cross-country (USA) flight. The samples were analyzed for a suite of flame retardant chemicals. To identify the possible sources for the brominated flame retardants, we used a portable XRF analyzer to quantify bromine concentrations in materials inside the airplanes. A wide range of flame retardant compounds were detected in 100% of the dust samples collected from airplanes, including BDEs 47, 99, 153, 183 and 209, tris(1,3-dichloro-isopropyl)phosphate (TDCPP), hexabromocyclododecane (HBCD) and bis-(2-ethylhexyl)-tetrabromo-phthalate (TBPH). Airplane dust contained elevated concentrations of BDE 209 (GM: 500 ug/g; range: 2,600 ug/g) relative to other indoor environments, such as residential and commercial buildings, and the hands of participants after a cross-country flight contained elevated BDE 209 concentrations relative to the general population. TDCPP, a known carcinogen that was removed from use in children's pajamas in the 1970's although still used today in other consumer products, was detected on 100% of airplanes in concentrations similar to those found in residential and commercial locations. This study adds to the limited body of knowledge regarding exposure to flame retardants on commercial aircraft, an environment long hypothesized to be at risk for maximum exposures due to strict flame retardant standards for aircraft materials. Our findings indicate that flame retardants are widely used in many airplane components and all airplane types, as

  2. A Polycarbonate/Magnesium Oxide Nanocomposite with High Flame Retardancy.

    Science.gov (United States)

    Dong, Quanxiao; Gao, Chong; Ding, Yanfen; Wang, Feng; Wen, Bin; Zhang, Shimin; Wang, Tongxin; Yang, Mingshu

    2012-01-15

    A new flame retardant polycarbonate/magnesium oxide (PC/MgO) nanocomposite, with high flame retardancy was developed by melt compounding. The effect of MgO to the flame retardancy, thermal property, and thermal degradation kinetics were investigated. Limited oxygen index (LOI) test revealed that a little amount of MgO (2 wt %) led to significant enhancement (LOI = 36.8) in flame retardancy. Thermogravimetric analysis results demonstrated that the onset temperature of degradation and temperature of maximum degradation rate decreased in both air and N 2 atmosphere. Apparent activation energy was estimated via Flynn-Wall-Ozawa method. Three steps in the thermal degradation kinetics were observed after incorporation of MgO into the matrix and the additive raised activation energies of the composite in the full range except the initial stage. It was interpreted that the flame retardancy of PC was influenced by MgO through the following two aspects: on the one hand, MgO catalyzed the thermal-oxidative degradation and accelerated a thermal protection/mass loss barrier at burning surface; on the other hand, the filler decreased activation energies in the initial step and improved thermal stability in the final period.

  3. Synergistic effect of carbon nanotube and clay for improving the flame retardancy of ABS resin

    Energy Technology Data Exchange (ETDEWEB)

    Ma Haiyun [Institute of Polymer Composites, Key Laboratory of Macromolecular Synthesis and Functionalization, Zhejiang University, Hangzhou 310027 (China); Tong Lifang [Institute of Polymer Composites, Key Laboratory of Macromolecular Synthesis and Functionalization, Zhejiang University, Hangzhou 310027 (China); Xu Zhongbin [Institute of Polymer Composites, Key Laboratory of Macromolecular Synthesis and Functionalization, Zhejiang University, Hangzhou 310027 (China); Fang Zhengping [Institute of Polymer Composites, Key Laboratory of Macromolecular Synthesis and Functionalization, Zhejiang University, Hangzhou 310027 (China)

    2007-09-19

    Synergistic effect between multi-walled carbon nanotubes (MWNTs) and clay on improving the flame retardancy of acrylonitrile-butadiene-styrene (ABS) resin was studied. Flammability properties measured by a cone calorimeter revealed that incorporation of clay and MWNTs into ABS resin significantly reduced the peak heat release rate (PHRR) and slowed down the whole combustion process compared to the individually filled system based on clay or MWNTs. The flame retardancy of the ABS/clay/MWNTs nanocomposites was strongly affected by the formation of a network structure. Linear viscoelastic properties of the ABS nanocomposites showed that the coexistence of clay and MWNTs can enhance the network structure which can hinder the movement of polymer chains and improve flame retardancy. From transmission electron microscope analysis, MWNTs were shortened after combustion and there was no significant change in their diameters. For chars of ABS/clay/MWNTs nanocomposites, some MWNTs ran across between clay layers, indicating a strong interaction existed between clay and MWNTs. The existence of clay enhanced the graphitization degree of MWNTs during combustion. Clay can assist the elimination of dislocations and defects and the rearrangement of crystallites. Al{sub 2}O{sub 3}, one of the components of clay, acts as the catalyst of graphitization.

  4. Development of low-smoke, flame-retarding cables

    International Nuclear Information System (INIS)

    Kato, H.; Kanemitsuya, K.; Furukawa, K.; Mio, K.

    1983-01-01

    A great deal of attention has been given to the potential fire hazard of combustion gases from organic materials. Although cable industries have developed flame-retarding organic materials for the insulation and jacketing of wires and cables, there was insufficient prevention of toxic gas formation during combustion. To cope with these problems associated with conventional PVC cables, the authors have directed to develop low-smoke, flame-retarding plasticized PVC formulations retaining the original mechanical, electrical and aging properties. A series of basic investigations on smoke suppression followed by an evaluation on practical cables could indicate some effective means to end these problems. This paper describes the results and discussion on smoke suppressing study of plasticized PVC as well as behavior and characteristics of the low-smoke, flame-retarding PVC wires and cables using these materials. (author)

  5. Halogenated flame retardants in bobcats from the midwestern United States.

    Science.gov (United States)

    Boyles, Esmarie; Tan, Hongli; Wu, Yan; Nielsen, Clayton K; Shen, Li; Reiner, Eric J; Chen, Da

    2017-02-01

    In response to the restrictions of polybrominated diphenyl ether (PBDE) flame retardants in various consumer products, alternative halogenated flame retardants have been subjected to increased use. Compared to aquatic ecosystems, relatively little information is available on the contamination of alternative flame retardants in terrestrial ecosystems, especially with regards to mammalian wildlife. In this study we used a top terrestrial carnivore, the bobcat (Lynx rufus), as a unique biomonitoring species for assessing flame retardant contamination in the Midwestern United States (U.S.) terrestrial ecosystems. Concentrations of ∑PBDEs (including all detectable PBDE congeners) ranged from 8.3 to 1920 ng/g lipid weight (median: 50.3 ng/g lw) in livers from 44 bobcats collected during 2013-2014 in Illinois. Among a variety of alternative flame retardants screened, Dechloranes (including anti- and syn-Dechlorane Plus and Dechlorane-602, 603, and 604), tetrabromo-o-chlorotoluene (TBCT), and hexabromocyclododecane (HBCD) were also frequently detected, with median concentrations of 28.7, 5.2, and 11.8 ng/g lw, respectively. Dechlorane analogue compositions in bobcats were different from what has been reported in other studies, suggesting species- or analogue-dependent bioaccumulation, biomagnification, or metabolism of Dechlorane chemicals in different food webs. Our findings, along with previously reported food web models, suggest Dechloranes may possess substantial bioaccumulation and biomagnification potencies in terrestrial mammalian food webs. Thus, attention should be given to these highly bioavailable flame retardants in future environmental biomonitoring and risk assessments in a post-PBDE era. Copyright © 2016. Published by Elsevier Ltd.

  6. Mineralisation and primary biodegradation of aromatic organophosphorus flame retardants in activated sludge

    NARCIS (Netherlands)

    Jurgens, S.S.; Helmus, R.; Waaijers, S.L.; Uittenbogaard, D.; Dunnebier, D.; Vleugel, M.; Kraak, M.H.S.; de Voogt, P.; Parsons, J.R.

    2014-01-01

    Halogen-free flame retardants (HFFRs), such as the aromatic organophosphorus flame retardants (OPFRs) triphenyl phosphate (TPHP), resorcinol bis(diphenylphosphate) (PBDPP) and bisphenol A bis(diphenylphosphate) (BPA-BDPP) have been proposed as potential replacements for brominated flame retardants

  7. Green Flame Retardant Cotton Highlofts for Mattresses and Upholstered Furniture

    Science.gov (United States)

    Green flame retardant (FR) barrier fabric is environmentally-friendly because it is from a natural renewable resource, biodegradable, economical, employing greige cotton that is soft to touch. Greige unbleached cotton is cheaper and softer than bleached cotton, thus, increasing its marketability par...

  8. Ecotoxicity and biodegradability of new brominated flame retardants: A review

    Czech Academy of Sciences Publication Activity Database

    Ezechiáš, Martin; Covino, Stefano; Cajthaml, Tomáš

    2014-01-01

    Roč. 110, č. 2 (2014), s. 153-167 ISSN 0147-6513 R&D Projects: GA MŠk(CZ) EE2.3.30.0003; GA TA ČR TE01020218 Institutional support: RVO:61388971 Keywords : Ecotoxicity * brominated flame retardants * biodegradation * review Subject RIV: EE - Microbiology, Virology Impact factor: 2.762, year: 2014

  9. Cone calorimeter evaluation of two flame retardant cotton fabrics

    Science.gov (United States)

    Robert H. White; Sunghyun Nam; Dharnidhar V. Parikh

    2012-01-01

    Unbleached (gray) cotton needle-punched nonwoven (NW) fabrics with 12.5% polypropylene scrim were treated with two phosphate–nitrogen-based flame retardant (FR) formulations, Southern Regional Research Center (SRRC)-1 and SRRC-2. The SRRC-1 formulation contains diammonium phosphate as the FR chemical along with urea and dimethyloldihydroxyethyleneurea. Because a trace...

  10. Neurotoxicity and risk assessment of brominated and alternative flame retardants.

    Science.gov (United States)

    Hendriks, Hester S; Westerink, Remco H S

    2015-01-01

    Brominated flame retardants (BFRs) are widely used chemicals that prevent or slow the onset and spreading of fire. Unfortunately, many of these compounds pose serious threats for human health and the environment, indicating an urgent need for safe(r) and less persistent alternative flame retardants (AFRs). As previous research identified the nervous system as a sensitive target organ, the neurotoxicity of past and present flame retardants is reviewed. First, an overview of the neurotoxicity of BFRs in humans and experimental animals is provided, and some common in vitro neurotoxic mechanisms of action are discussed. The combined epidemiological and toxicological studies clearly underline the need for replacing BFRs. Many potentially suitable AFRs are already in use, despite the absence of a full profile of their environmental behavior and toxicological properties. To prioritize the suitability of some selected halogenated and non-halogenated organophosphorous flame retardants and inorganic halogen-free flame retardants, the available neurotoxic data of these AFRs are discussed. The suitability of the AFRs is rank-ordered and combined with human exposure data (serum concentrations, breast milk concentrations and house dust concentrations) and physicochemical properties (useful to predict e.g. bioavailability and persistence in the environment) for a first semi-quantitative risk assessment of the AFRs. As can be concluded from the reviewed data, several BFRs and AFRs share some neurotoxic effects and modes of action. Moreover, the available neurotoxicity data indicate that some AFRs may be suitable substitutes for BFRs. However, proper risk assessment is hampered by an overall scarcity of data, particularly regarding environmental persistence, human exposure levels, and the formation of breakdown products and possible metabolites as well as their toxicity. Until these data gaps in environmental behavioral and toxicological profiles are filled, large scale use of

  11. Flame-retardant carbon nanotube films

    Science.gov (United States)

    Janas, Dawid; Rdest, Monika; Koziol, Krzysztof K. K.

    2017-07-01

    We have demonstrated fire-retardancy properties of a polymer matrix-free CNT film for the first time. As compared with classical fire-retardant materials such as Kevlar, Twaron or Nomex, the CNT film showed a spectrum of advantages. The material is lightweight, flexible and well-adherent to even the most complicated shapes. The results have showed that by using CNTs for fire-retardancy we can extend the operational time almost two-fold, what makes CNTs a much better protection than the solutions employed nowadays. We believe that among other great properties of CNT, their macroscopic assemblies such as CNT films show significant potential for becoming a fire protective coating, which exhibits high performance in not sustaining fire.

  12. Radiation-grafting of flame retardants on flax fabrics - A comparison between different flame retardant structures

    Science.gov (United States)

    Teixeira, Marie; Sonnier, Rodolphe; Otazaghine, Belkacem; Ferry, Laurent; Aubert, Mélanie; Tirri, Teija; Wilén, Carl-Eric; Rouif, Sophie

    2018-04-01

    Three unsaturated compounds bearing respectively phosphate, aryl bromide and sulfenamide moieties were used as flame retardants (FR) for flax fabrics. Due to the presence of carbon-carbon double bonds, radiation-grafting was considered to covalently bond these FR onto fiber structure. Grafting efficiency and location of FR molecules were investigated by weight measurements and SEM-EDX observations. Flammability and especially self-extinguishment were assessed by thermogravimetric analysis, pyrolysis-combustion flow calorimetry and a non-standardized fire test already used in previous studies. All FRs were able to diffuse into elementary fiber bulk. Nevertheless only the phosphonated monomer (noted FR-P) was significantly grafted onto flax. Self-extinguishment was obtained for fabrics containing at least around 0.5 wt% of phosphorus. On the contrary the FR content of flax fibers after radiation-grafting procedure and washing was negligible for FR-S and FR-Br, evidencing that these molecules have not been grafted upon irradiation. Moreover, the combination of these molecules prevents the radiation-grafting of other molecules which showed good grafting rate when used alone.

  13. Part I. Improved flame retardant textiles. Part II. Novel approach to layer-by-layer processing for flame retardant textiles.

    Science.gov (United States)

    In this presentation, new approaches for flame retardant textile by using supercritical carbon dioxide (scCO2) and layer-by-layer processing will be discussed. Due to its environmentally benign character, the scCO2 is considered in green chemistry as a substitute for organic solvents in chemical re...

  14. Neurotoxicity of past, present and future flame retardants - neurotoxic hazard characterization and risk assessment of (alternative) flame retardants

    NARCIS (Netherlands)

    Hendriks, H.S.

    2014-01-01

    Brominated flame retardants (BFRs), and to a lesser extent polychlorinated biphenyls (PCBs), are widely used chemicals that prevent or slow the onset and spreading of fire in order to reduce injuries and death. Unfortunately, many of these compounds pose serious threats for human health and the

  15. Flame retardancy and ultraviolet resistance of silk fabric coated by graphene oxide

    OpenAIRE

    Ji Yi-Min; Cao Ying-Ying; Chen Guo-Qiang; Xing Tie-Ling

    2017-01-01

    Silk fabrics were coated by graphene oxide hydrosol in order to improve its flame retardancy and ultraviolet resistance. In addition, montmorillonoid was doped into the graphene oxide hydrosol to further improve the flame retardancy of silk fabrics. The flame retardancy and ultraviolet resistance were mainly characterized by limiting oxygen index, vertical flame test, smoke density test, and ultraviolet protection factor. The synergistic effect of graphene oxide and montmorillonoid on the the...

  16. Plasma-enhanced synthesis of green flame retardant cellulosic materials

    Science.gov (United States)

    Totolin, Vladimir

    The natural fiber-containing fabrics and composites are more environmentally friendly, and are used in transportation (automobiles, aerospace), military applications, construction industries (ceiling paneling, partition boards), consumer products, etc. Therefore, the flammability characteristics of the composites based on polymers and natural fibers play an important role. This dissertation presents the development of plasma assisted - green flame retardant coatings for cellulosic substrates. The overall objective of this work was to generate durable flame retardant treatment on cellulosic materials. In the first approach sodium silicate layers were pre-deposited onto clean cotton substrates and cross linked using low pressure, non-equilibrium oxygen plasma. A statistical design of experiments was used to optimize the plasma parameters. The modified cotton samples were tested for flammability using an automatic 45° angle flammability test chamber. Aging tests were conducted to evaluate the coating resistance during the accelerated laundry technique. The samples revealed a high flame retardant behavior and good thermal stability proved by thermo-gravimetric analysis. In the second approach flame retardant cellulosic materials have been produced using a silicon dioxide (SiO2) network coating. SiO 2 network armor was prepared through hydrolysis and condensation of the precursor tetraethyl orthosilicate (TEOS), prior coating the substrates, and was cross linked on the surface of the substrates using atmospheric pressure plasma (APP) technique. Due to protection effects of the SiO2 network armor, the cellulosic based fibers exhibit enhanced thermal properties and improved flame retardancy. In the third approach, the TEOS/APP treatments were extended to linen fabrics. The thermal analysis showed a higher char content and a strong endothermic process of the treated samples compared with control ones, indicating a good thermal stability. Also, the surface analysis proved

  17. Flame Retardant Effect of Nano Fillers on Polydimethylsiloxane Composites.

    Science.gov (United States)

    Jagdale, Pravin; Salimpour, Samera; Islam, Md Hujjatul; Cuttica, Fabio; Hernandez, Francisco C Robles; Tagliaferro, Alberto; Frache, Alberto

    2018-02-01

    Polydimethylsiloxane has exceptional fire retardancy characteristics, which make it a popular polymer in flame retardancy applications. Flame retardancy of polydimethylsiloxane with different nano fillers was studied. Polydimethylsiloxane composite fire property varies because of the shape, size, density, and chemical nature of nano fillers. In house made carbon and bismuth oxide nano fillers were used in polydimethylsiloxane composite. Carbon from biochar (carbonised bamboo) and a carbon by-product (carbon soot) were selected. For comparative study of nano fillers, standard commercial multiwall carbon nano tubes (functionalised, graphitised and pristine) as nano fillers were selected. Nano fillers in polydimethylsiloxane positively affects their fire retardant properties such as total smoke release, peak heat release rate, and time to ignition. Charring and surface ceramization are the main reasons for such improvement. Nano fillers in polydimethylsiloxane may affect the thermal mobility of polymer chains, which can directly affect the time to ignition. The study concludes that the addition of pristine multiwall carbon nano tubes and bismuth oxide nano particles as filler in polydimethylsiloxane composite improves the fire retardant property.

  18. Environmental Impact of Flame Retardants (Persistence and Biodegradability

    Directory of Open Access Journals (Sweden)

    Asher Brenner

    2009-02-01

    Full Text Available Flame-retardants (FR are a group of anthropogenic environmental contaminants used at relatively high concentrations in many applications. Currently, the largest market group of FRs is the brominated flame retardants (BFRs. Many of the BFRs are considered toxic, persistent and bioaccumulative. Bioremediation of contaminated water, soil and sediments is a possible solution for the problem. However, the main problem with this approach is the lack of knowledge concerning appropriate microorganisms, biochemical pathways and operational conditions facilitating degradation of these chemicals at an acceptable rate. This paper reviews and discusses current knowledge and recent developments related to the environmental fate and impact of FRs in natural systems and in engineered treatment processes.

  19. Fabrication of cotton fabric with superhydrophobicity and flame retardancy.

    Science.gov (United States)

    Zhang, Ming; Wang, Chengyu

    2013-07-25

    A simple and facile method for fabricating the cotton fabric with superhydrophobicity and flame retardancy is described in the present work. The cotton fabric with the maximal WCA of 160° has been prepared by the covalent deposition of amino-silica nanospheres and the further graft with (heptadecafluoro-1,1,2,2-tetradecyl) trimethoxysilane. The geometric microstructure of silica spheres was measured by transmission electron microscopy (TEM). The cotton textiles before and after treatment were characterized by using scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The wetting behavior of cotton samples was investigated by water contact angle measurement. Moreover, diverse performances of superhydrophobic cotton textiles have been evaluated as well. The results exhibited the outstanding superhydrophobicity, excellent waterproofing durability and flame retardancy of the cotton fabric after treatment, offering a good opportunity to accelerate the large-scale production of superhydrophobic textiles materials for new industrial applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Exposures, Mechanisms, and Impacts of Endocrine-Active Flame Retardants

    OpenAIRE

    Dishaw, Laura; Macaulay, Laura; Roberts, Simon C.; Stapleton, Heather M.

    2014-01-01

    This review summarizes the endocrine and neurodevelopmental effects of two current-use additive flame retardants (FRs), tris (1,3-dichloro-isopropyl) phosphate (TDCPP) and Firemaster® 550 (FM 550), and the recently phased-out polybrominated diphenyl ethers (PBDEs), all of which were historically or are currently used in polyurethane foam applications. Use of these chemicals in consumer products has led to widespread exposure in indoor environments. PBDEs and their hydroxylated metabolites app...

  1. Intumescent Biobased-Polylactide Films to Flame Retard Nonwovens

    OpenAIRE

    Christelle Reti; Mathilde Casetta, Ph.D.; Sophie Duquesne, Ph.D.; René Delobel; Serge Bourbigot; Jérémie Soulestin

    2009-01-01

    The work focuses on the development of a newprocess to flame retard nonwovens, using films basedon renewable resources. Films consist in intumescentformulations of polylactic acid (PLA), ammoniumpolyphosphate (APP) blended with lignin or starchand are coated on hemp or wool nonwovens. Theobjective of this study was to investigate the fireretardant and mechanical properties of textilesprotected by FR PLA films for potential use inbuilding applications. Horizontal and vertical flamespread tests...

  2. Development of thermoregulating microcapsules with cyclotriphosphazene as a flame retardant agent

    Science.gov (United States)

    Szczotok, A. M.; Carmona, M.; Serrano, A.; Kjøniksen, A. L.; Rodriguez, J. F.

    2017-10-01

    Thermoregulating microcapsules containing phase change material (Rubitherm®RT27) was produced by using the suspension-like polymerization technique with styrene (St), divinylbenzene (DVB) and hexa(methacryloylethylenedioxy) cyclotriphosphazene (PNC-HEMA) as co-monomers. The effect of PNC-HEMA for improving the flame retardant properties of the microcapsules were analyzed by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). It was found that the thermal energy storage (TES) capacity of the microcapsules increased in the presence of PNC-HEMA. However, the morphology of the microcapsules became irregular when the content of monomer with flame retardant properties was increased. Thermogravimetric analysis performed under atmospheric air confirmed that the PNC-HEMA raised the amount of residue after the burning process, proving the formation of thermally stable char. Thus, these materials could be considered as an important alternative to commonly used microcapsules containing phase change materials (PCMs), where a lower flammability is required for their application.

  3. Flame retardancy and ultraviolet resistance of silk fabric coated by graphene oxide

    Directory of Open Access Journals (Sweden)

    Ji Yi-Min

    2017-01-01

    Full Text Available Silk fabrics were coated by graphene oxide hydrosol in order to improve its flame retardancy and ultraviolet resistance. In addition, montmorillonoid was doped into the graphene oxide hydrosol to further improve the flame retardancy of silk fabrics. The flame retardancy and ultraviolet resistance were mainly characterized by limiting oxygen index, vertical flame test, smoke density test, and ultraviolet protection factor. The synergistic effect of graphene oxide and montmorillonoid on the thermal stabilization property of the treated silk fabrics was also investigated. The results show that the treated silk fabrics have excellent flame retardancy, thermal stability, smoke suppression, and ultraviolet resistance simultaneously.

  4. Interlaboratory study of novel halogenated flame retardants: INTERFLAB.

    Science.gov (United States)

    Melymuk, Lisa; Goosey, Emma; Riddell, Nicole; Diamond, Miriam L

    2015-09-01

    Flame retardants (FRs) have come under considerable scientific and public scrutiny over the past decade. A lack of reference materials and standardized analytical methods has resulted in questions regarding the variation of measurements from different studies. We evaluated this variation by performing an international interlaboratory study assessing analytical capabilities as well as the accuracy and precision of results for a range of flame retardants (International Flame Retardant Laboratory Study, INTERFLAB). Thirteen international research laboratories participated in a blind interlaboratory comparison of 24 FRs. Results demonstrate good precision within replicates of test mixtures from individual laboratories, but problematic accuracy for several FRs and laboratories. Large ranges in the values reported for decabromodiphenylethane (DBDPE), tris(1,3-dichloropropyl)phosphate (TDCIPP), tetrabromobisphenol-A (TBBPA), and hexabromocyclododecane (HBCD) (>50 % relative standard deviations among measured values) and large deviations from the reference values (>25 % bias in accuracy) suggest potential problems for comparability of results. DBDPE, HBCD, and TBBPA had significantly poorer accuracy and precision, suggesting that current analytical methods are not providing reliable results for these FRs.

  5. Photochemical and microbial transformation of emerging flame retardants: cause for concern?

    Science.gov (United States)

    Chen, Da; Hale, Robert C; Letcher, Robert J

    2015-04-01

    Among anthropogenic chemicals, flame retardants have attracted mounting environmental concerns. In recent years, an increasing number of studies have been conducted worldwide to investigate flame-retardant sources, environmental distribution, wildlife and human exposure, and toxicity. Data generated have demonstrated that some flame-retardant substances such as polybrominated diphenyl ethers (PBDE) are persistent, bioaccumulative, and toxic to exposed organisms. However, comparatively much less attention has been paid to the mechanisms and products of environmental transformation of flame retardants. This lack of information undermines our understanding of the environmental behavior and fate of flame retardants, as well as the associated risks to environmental and human health. Photochemical and microbial transformation of flame retardants in various matrices and environmental compartments can elevate the toxicological significance of flame retardant exposure, via the formation of, for example, lesser halogenated but more bioaccumulative degradation products and toxic radicals. Such pathways raise concerns related to the environmental safety of some alternative flame retardants that are presumably safe and used to replace PBDEs. To fully assess the environmental risks, more research is needed to investigate the environmental transformation potential of emerging flame retardants including polymeric flame retardants. Enhanced analytical efforts are needed to better characterize transformation products and transient radicals. Additional mesocosm and field studies are needed to elucidate transformation kinetics and consequences under environmentally relevant conditions. © 2015 SETAC.

  6. Novel routes in flame retardancy of bisphenol A polycarbonate/impact modifier/aryl phosphate blends

    Energy Technology Data Exchange (ETDEWEB)

    Wawrzyn, Eliza

    2013-07-01

    The massive use of electronic engineering products accompanied by high demands on fire safety has led to increasing interest in environmentally friendly flame retardancy of bisphenol A polycarbonate (PC) based materials. In this work, novel routes for enhancing the flame retardancy of PC/Impact Modifier/Aryl phosphate were studied with respect to pyrolysis (TG, TG-FTIR, ATR-FTIR, NMR), flammability (LOI and UL 94) and fire behavior (cone calorimeter at different irradiations). To improve charring of PC/ABS{sub PTFE}+Aryl phosphate, the exchange of bisphenol A bis(diphenyl phosphate) (BDP) with novel aryl phosphates was proposed. Two novel flame retardants were synthesized: 3,3,5-trimethylcyclohexylbisphenol-bis(diphenyl phosphate) (TMC-BDP) and bisphenol A-bis(diethylphosphate) (BEP). TMC-BDP was more stable than BDP, thus gave a potential to increase the chemical reactions between the components of the PC/ABS{sub PTFE}+Aryl phosphate, whereas more reactive BEP was expected to increase the cross linking activity with the polymer matrix. Nevertheless, the corresponding blends did not enhance the flame retardancy compared to PC/ABS{sub PTFE}+BDP. BEP in PC/ABS{sub PTFE} preferred to cross-link with itself instead of with PC, thus it showed poor fire protection performance. TMC-BDP gave as good results as BDP in PC/ABS PTFE material. The results delivered evidence that BDP possesses a high degree of optimization in PC/ABS{sub PTFE} system. To provide a novel impact modifier improving not only mechanical properties but also the fire retardancy of PC/BDP material, the replacement of highly flammable acrylonitrile-butadiene-styrene (ABS) with silicon acrylate rubber (SiR) with high content of polydimethylsiloxane (PDMS) was studied. In PC/SiR{sub PTFE}/BDP the replacement of ABS is beneficial, but PDMS worsened the BDP gas phase and condensed phase action. PDMS reacted also with PC during combustion. PDMS-PC and PDMS-BDP interactions led to silicon dioxide. In fact, the

  7. Benefits of radical generators in flame retarded polymers: Review and new developments

    OpenAIRE

    Pfaendner, R.

    2014-01-01

    Radical generators as synergists in flame retarded polymers have been used in combination with brominated flame retardants for decades. However, due to the low thermal stability of radical generators under the usual polymer processing conditions the use was limited to selected applications e.g. in polystyrene foams. The need to find efficient halogen free flame retardants resulted inter alia in the discovery and commercialization of hindered amine light stabilizers based on alkoxyamines (NOR-...

  8. Engineering Biodegradable Flame Retardant Wood-Plastic Composites

    Science.gov (United States)

    Zhang, Linxi

    Wood-plastic composites (WPCs), which are produced by blending wood and polymer materials, have attracted increasing attentions in market and industry due to the low cost and excellent performance. In this research, we have successfully engineered WPC by melt blending Polylactic Acid (PLA) and Poly(butylene adipate-co-terphthalate) (PBAT) with recycled wood flour. The thermal property and flammability of the composite are significantly improved by introducing flame retardant agent resorcinol bis(biphenyl phosphate) (RDP). The mechanical and morphological properties are also investigated via multiple techniques. The results show that wood material has increased toughness and impact resistance of the PLA/PBAT polymer matrix. SEM images have confirmed that PLA and PBAT are immiscible, but the incompatibility is reduced by the addition of wood. RDP is initially dispersed in the blends evenly. It migrates to the surface of the sample after flame application, and serves as a barrier between the fire and underlying polymers and wood mixture. It is well proved in the research that RDP is an efficient flame retardant agent in the WPC system.

  9. Modification of poly(styrene-block-butadiene-block-styrene) [SBS] with phosphorus containing fire retardants

    DEFF Research Database (Denmark)

    Chernyy, Sergey; Ullah, Saif; Jomaas, Grunde

    2015-01-01

    An elaborate survey of the chemical modification methods for endowing highly flammable SBS with increased fire resistant properties by means of chemical modification of the polymer backbone with phosphorus containing fire retardant species is presented. Optimal conditions for free radical addition...... resulting in 20 mol% of poly(butadiene) block modification. Based on TGA results, organophosporus-modified SBS was found to be amenable to charring – a property which correlated directly with the reduced flammability of the modified polymer observed in Cone Calorimetry tests. Furthermore, conceptually novel...... application of the H3PO4 modified SBS as a fire retardant additive for bitumen material, in combination with synergetic melamine species, offered 25% better self-extinguishing properties of such formulation already at a low loading level of the fire retardant components (3.5 wt.%)....

  10. Recent Developments in Halogen Free Flame Retardants for Epoxy Resins for Electrical and Electronic Applications

    Science.gov (United States)

    Rakotomalala, Muriel; Wagner, Sebastian; Döring, Manfred

    2010-01-01

    The recent implementation of new environmental legislations led to a change in the manufacturing of composites that has repercussions on printed wiring boards (PWB). This in turn led to alternate processing methods (e.g., lead-free soldering), which affected the required physical and chemical properties of the additives used to impart flame retardancy. This review will discuss the latest advancements in phosphorus containing flame retardants for electrical and electronic (EE) applications and compare them with commercially available ones. The mechanism of degradation and flame retardancy of phosphorus flame retardants in epoxy resins will also be discussed. PMID:28883331

  11. Recent Developments in Halogen Free Flame Retardants for Epoxy Resins for Electrical and Electronic Applications.

    Science.gov (United States)

    Rakotomalala, Muriel; Wagner, Sebastian; Döring, Manfred

    2010-08-11

    The recent implementation of new environmental legislations led to a change in the manufacturing of composites that has repercussions on printed wiring boards (PWB). This in turn led to alternate processing methods (e.g., lead-free soldering), which affected the required physical and chemical properties of the additives used to impart flame retardancy. This review will discuss the latest advancements in phosphorus containing flame retardants for electrical and electronic (EE) applications and compare them with commercially available ones. The mechanism of degradation and flame retardancy of phosphorus flame retardants in epoxy resins will also be discussed.

  12. Recent Developments in Halogen Free Flame Retardants for Epoxy Resins for Electrical and Electronic Applications

    Directory of Open Access Journals (Sweden)

    Manfred Döring

    2010-08-01

    Full Text Available The recent implementation of new environmental legislations led to a change in the manufacturing of composites that has repercussions on printed wiring boards (PWB. This in turn led to alternate processing methods (e.g., lead-free soldering, which affected the required physical and chemical properties of the additives used to impart flame retardancy. This review will discuss the latest advancements in phosphorus containing flame retardants for electrical and electronic (EE applications and compare them with commercially available ones. The mechanism of degradation and flame retardancy of phosphorus flame retardants in epoxy resins will also be discussed.

  13. Inhalation a significant exposure route for chlorinated organophosphate flame retardants.

    Science.gov (United States)

    Schreder, Erika D; Uding, Nancy; La Guardia, Mark J

    2016-05-01

    Chlorinated organophosphate flame retardants (ClOPFRs) are widely used as additive flame retardants in consumer products including furniture, children's products, building materials, and textiles. Tests of indoor media in homes, offices, and other environments have shown these compounds are released from products and have become ubiquitous indoor pollutants. In house dust samples from Washington State, U.S.A., ClOPFRs were the flame retardants detected in the highest concentrations. Two ClOPFRs, tris(1,3-dichloro-2-propyl)phosphate (TDCPP or TDCIPP) and tris(2-chloroethyl)phosphate (TCEP), have been designated as carcinogens, and there is growing concern about the toxicity of the homologue tris(1-chloro-2-propyl)phosphate (TCPP or TCIPP). In response to concerns about exposure to these compounds, the European Union and a number of U.S. states have taken regulatory action to restrict their use in certain product categories. To better characterize exposure to ClOPFRs, inhalation exposure was assessed using active personal air samplers in Washington State with both respirable and inhalable particulate fractions collected to assess the likelihood particles penetrate deep into the lungs. Concentrations of ∑ClOPFRs (respirable and inhalable) ranged from 97.1 to 1190 ng m(-3) (mean 426 ng m(-3)), with TCPP detected at the highest concentrations. In general, higher levels were detected in the inhalable particulate fraction. Total intake of ClOPFRs via the inhalation exposure route was estimated to exceed intake via dust ingestion, indicating that inhalation is an important route that should be taken into consideration in assessments of these compounds. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Smoke suppression properties of ferrite yellow on flame retardant thermoplastic polyurethane based on ammonium polyphosphate

    International Nuclear Information System (INIS)

    Chen, Xilei; Jiang, Yufeng; Jiao, Chuanmei

    2014-01-01

    Highlights: • Smoke suppression of FeOOH on flame retardant TPU composites has been investigated. • FeOOH has excellent smoke suppression abilities for flame retardant TPU composites. • FeOOH has good ability of char formation, hence improved smoke suppression property. -- Abstract: This article mainly studies smoke suppression properties and synergistic flame retardant effect of ferrite yellow (FeOOH) on flame retardant thermoplastic polyurethane (TPU) composites using ammonium polyphosphate (APP) as a flame retardant agent. Smoke suppression properties and synergistic flame retardant effect of FeOOH on flame retardant TPU composites were intensively investigated by smoke density test (SDT), cone calorimeter test (CCT), scanning electron microscopy (SEM), and thermal-gravimetric analysis (TGA). Remarkably, the SDT results show that FeOOH can effectively decrease the amount of smoke production with or without flame. On the other hand, the CCT data reveal that the addition of FeOOH can apparently reduce heat release rate (HRR), total heat release (THR), and total smoke release (TSR), etc. Here, FeOOH is considered to be an effective smoke suppression agent and a good synergism with APP in flame retardant TPU composites, which can greatly improve the structure of char residue realized by TGA and SEM results

  15. Global Consumption of Flame Retardants and Related Environmental Concerns: A Study on Possible Mechanical Recycling of Flame Retardant Textiles

    Directory of Open Access Journals (Sweden)

    Sohail Yasin

    2016-05-01

    Full Text Available Flame retardants (FRs have been around us for decades to increase the chances of survival against fire or flame by limiting its propagation. The FR textiles, irrespective of their atmospheric presence are used in baby clothing, pushchairs, car seats, etc. The overall FR market in Asia, Europe, and the United States in 2007 was around 1.8 million metric tonnes. It is estimated that the worldwide consumption of FRs will reach 2.8 million tonnes in 2018. Unfortunately, a sustainable approach for textile waste, especially in the case of FR textiles, is absent. Incineration and landfill of FR textiles are hindered by various toxic outcomes. To address the need for sustainable methods of discarding FR textiles, the mechanical recycling of cotton curtains was evaluated.

  16. Aluminum phosphate microcapsule flame retardants for flexible polyurethane foams

    Science.gov (United States)

    Zhang, Bin; Liu, Hong; Han, Jian

    2018-04-01

    In this study, highly efficient flame-retardant aluminum phosphate (ALP) microcapsules were synthesized from ALP and ammonium phosphomolybdate trihydrate. The chemical structure of the ALP microcapsules was characterized by scanning electron microscopy and elemental analysis, and the thermal degradation behavior was investigated by thermogravimetric analysis (TGA). Subsequently, flexible polyurethane (PU) foams were prepared with the ALP microcapsules. Limiting oxygen index (LOI) tests, vertical burning tests, smoke density rating (SDR), and cone calorimetric tests were employed to investigate the combustion of the materials. The results showed that the flexible PU foams with 15 parts per hundred polyol by weight (pphp) ALP microcapsules passed the vertical burning test and they had an increased LOI value of 28.5%. The SDR value for PU/20 pphp ALP microcapsule composites was about 16.0% and the SDR value for the pure PU was about 29.0%. The corresponding flame-retardant mechanism was investigated by Fourier transform infrared spectroscopy, TGA, Pyrolysis Gas Chromatography Mass Spectrometry (Py-GC/MS) tests, and energy-dispersive X-ray spectrometry.

  17. Flame retardancy of highly filled polyamide 6/clay nanocomposites

    International Nuclear Information System (INIS)

    Dasari, Aravind; Yu Zhongzhen; Mai Yiuwing; Liu Songlin

    2007-01-01

    To obtain an in-depth physical knowledge of the protective barrier stability and uniformity under fire conditions, we prepared highly filled polyamide 6/organoclay nanocomposites and characterized their thermal and flammability properties. The objectives were to identify a critical composition that is needed to form a stable char with no apertures or cracks and to gain a thorough understanding of the mechanisms of flame retardancy. It was shown that there is no need for higher percentages of clay and even smaller amounts of clay (<10 wt%) should be enough to achieve good fire performance. Factors such as incoherency, poor stability and non-uniformity of the char or the presence of large cracks and formation of island-like structures were insignificant in slowing down the heat release and mass loss rates. Nevertheless, there was no stage during the flammability test where the fire completely extinguished even when the protective layer was stable and free from major cracks/apertures. Based on these results, new insights and approaches to process better flame retardant polymer nanocomposites are discussed

  18. Potential estrogenic effects of phosphorus-containing flame retardants.

    Science.gov (United States)

    Zhang, Quan; Lu, Meiya; Dong, Xiaowu; Wang, Cui; Zhang, Chunlong; Liu, Weiping; Zhao, Meirong

    2014-06-17

    As the substitute of polybrominated diphenyl ethers (PBDEs), further assessments about the potential ecological safety and health risks of phosphorus-containing flame retardants (PFRs) are required because the worldwide demand for PFRs has been increasing every year. In this study, we examined the agonistic/antagonistic activity of a group of PFRs by three in vitro models (luciferase reporter gene assay, yeast two-hybrid assay, and E-screen assay). Molecule docking was used to further explain the interactions between ERα and PFRs. Data from luciferase reporter gene analysis showed three members of the nine tested PFRs significantly induced estrogenic effects, with the order of TPP > TCP > TDCPP, while TCEP and TEHP have remarkable antiestrogenic properties with calculated REC20 and RIC20 values of 10(-6) M or lower. Results from the luciferase reporter gene method are generally consistent with results obtained from the yeast two-hybrid assay and E-screen, except for the positive estrogenic activity of TBP in E-screen testing. Docking results showed that binding between ligands and ERα was stabilized by hydrophobic interactions. As a proposed alternative for brominated flame retardant, PFRs may have anti/estrogenic activity via ERα at the low dose typical of residue in environmental matrix or animals. PFRs with a short chain, halogen, and benzene ring in the substituent group tend to be estrogenic. Our research suggests that comprehensive evaluations, including health and ecological assessments, are required in determining whether PFRs are preferable as an emerging industrial substitute.

  19. Flame Retardancy of Chemically Modified Lignin as Functional Additive to Epoxy Nanocomposites

    Science.gov (United States)

    John A. Howarter; Gamini P. Mendis; Alex N. Bruce; Jeffrey P. Youngblood; Mark A. Dietenberger; Laura Hasburgh

    2015-01-01

    Epoxy printed circuit boards are used in a variety of electronics applications as rigid, thermally stable substrates. Due to the propensity of components on the boards, such as batteries and interconnects, to fail and ignite the epoxy, flame retardant additives are required to minimize fire risk. Currently, industry uses brominated flame retardants, such as TBBPA, to...

  20. Phosphorylated lignin as a halogen-free flame retardant additive for epoxy composites

    Science.gov (United States)

    Gamini P. Mendis; Sydney G. Weiss; Matthew Korey; Charles R. Boardman; Mark Dietenberger; Jeffrey P. Youngblood; John A. Howarter

    2016-01-01

    Sustainable, non-halogenated flame retardants are desired for a variety of industry applications. Lignin, as an industrially processed wood derivative, has been examined as a potential sustainable flame retardant additive to polymer systems. Here, the lignin is phosphorylated using a pyridine-catalysed esterification reaction with diphenyl phosphoryl chloride to...

  1. Understanding the mechanism of action of triazine-phosphonate derivatives as flame retardants for cotton fabrics

    Science.gov (United States)

    Countless hours of research and studies on triazine, phosphonate and their combination have provided insightful information into their flame retardant properties on polymeric systems. However, only limited number of studies shed light on the mechanism of flame retardant cotton fabrics. The purpose...

  2. Effect of DPK flame retardant on combustion characteristics and fire safety of PVC membrane

    Directory of Open Access Journals (Sweden)

    Yu Xia

    2017-09-01

    Full Text Available In this work, the performances of PVC membrane with DPK flame retardant and without flame retardant were investigated under external radiation flux. The experimental results showed that the addition of DPK flame retardant can greatly reduce the peak heat release, total heat release of the material, and increase the time to peak heat release, time to ignition and the production of poisonous gas CO. By introducing the mathematical evaluation model and specifying the reliable evaluation indexes, the safety indexes of two kinds of materials are obtained. The results showed that by adding the flame retardant, the safety indexes of the PVC membranes were increased to 161% and 156% under 40 kw/m2 and 50 kw/m2 respectively, which is accordant to the result of experiments and suggest that the presence of DPK has a good flame retardant effect.

  3. Exploring the Modes of Action of Phosphorus-Based Flame Retardants in Polymeric Systems

    Directory of Open Access Journals (Sweden)

    Sebastian Rabe

    2017-04-01

    Full Text Available Phosphorus-based flame retardants were incorporated into different, easily preparable matrices, such as polymeric thermoset resins and paraffin as a proposed model for polyolefins and investigated for their flame retardancy performance. The favored mode of action of each flame retardant was identified in each respective system and at each respective concentration. Thermogravimetric analysis was used in combination with infrared spectroscopy of the evolved gas to determine the pyrolysis behavior, residue formation and the release of phosphorus species. Forced flaming tests in the cone calorimeter provided insight into burning behavior and macroscopic residue effects. The results were put into relation to the phosphorus content to reveal correlations between phosphorus concentration in the gas phase and flame inhibition performance, as well as phosphorus concentration in the residue and condensed phase activity. Total heat evolved (fire load and peak heat release rate were calculated based on changes in the effective heat of combustion and residue, and then compared with the measured values to address the modes of action of the flame retardants quantitatively. The quantification of flame inhibition, charring, and the protective layer effect measure the non-linear flame retardancy effects as functions of the phosphorus concentration. Overall, this screening approach using easily preparable polymer systems provides great insight into the effect of phosphorus in different flame retarded polymers, with regard to polymer structure, phosphorus concentration, and phosphorus species.

  4. Recycling of plastic waste: Screening for brominated flame retardants (BFRs)

    DEFF Research Database (Denmark)

    Pivnenko, Kostyantyn; Granby, Kit; Eriksson, Eva

    2017-01-01

    flame retardants (PBDEs and HBCD) identified in the plastic samples illustrates that circular material flows may be contaminated for extended periods. The screening clearly showed a need for improved documentation and monitoring of the presence of BFRs in plastic waste routed to recycling....... on the other hand, has resulted in dispersion and accumulation of selected BFRs in the environment and receiving biota. A wide range of plastic products may contain BFRs. This affects the quality of waste plastics as secondary resource: material recycling may potentially reintroduce the BFRs into new plastic......,4,6-TBP)), hexabromocyclododecane stereoisomers (α-, β-, and γ-HBCD), as well as selected polybrominated diphenyl ethers (PBDEs) in samples of household waste plastics, virgin and recycled plastics. A considerable number of samples contained BFRs, with highest concentrations associated with acrylonitrile...

  5. Exposures, mechanisms, and impacts of endocrine-active flame retardants.

    Science.gov (United States)

    Dishaw, Laura V; Macaulay, Laura J; Roberts, Simon C; Stapleton, Heather M

    2014-12-01

    This review summarizes the endocrine and neurodevelopmental effects of two current-use additive flame retardants (FRs), tris (1,3-dichloro-isopropyl) phosphate (TDCPP) and Firemaster(®) 550 (FM 550), and the recently phased-out polybrominated diphenyl ethers (PBDEs), all of which were historically or are currently used in polyurethane foam applications. Use of these chemicals in consumer products has led to widespread exposure in indoor environments. PBDEs and their hydroxylated metabolites appear to primarily target the thyroid system, likely due to their structural similarity to endogenous thyroid hormones. In contrast, much less is known about the toxicity of TDCPP and FM 550. However, recent in vitro and in vivo studies suggest that both should be considered endocrine disruptors as studies have linked TDCPP exposure with changes in circulating hormone levels, and FM 550 exposure with changes in adipogenic and osteogenic pathways. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Organophosphorus flame retardants – Toxicity and influence on human health

    Directory of Open Access Journals (Sweden)

    Elżbieta Bruchajzer

    2015-06-01

    Full Text Available Organophosphorus flame retardants (flame retardants, FRs have been used for several decades in many industries, including the production of dyes, varnishes, adhesives, synthetic resins, polyvinyl chloride, hydraulic fluids, plastics and textiles. Their importance in recent times has increased due to i.a., significantly reduced use of polybrominated diphenyl ethers (PBDEs – persistent organic pollutants, dangerous for the environment. The aim of this study was to review the available literature data concerning phosphorous FRs primarily for neurotoxic, fertility, reproductive and carcinogenic effects. The analysis concerned the following most commonly used substances: tris(2-ethylhexylphosphate (TEHP, tris(2-butoxyethylphosphate (TBEP, triphenyl phosphate (TPP, tris(2-chloroethylphosphate (TCEP, tetrakis(hydroxymethyl-phosphonium chloride (THPC, tributyl phosphate (TBP, tricresyl phosphate (TCP, tris(2-chloroisopropylphosphate (TCPP, tris(1,3-dichloroisopropylphosphate (TDCP and tetrakis(hydroxymethyl phosphonium sulphate (THPS. In animal studies neurotoxic effects were found after exposure to TBEP, THPC, TBP and TCP, while in humans they were observed only after exposure to TCP. TCEP, THPS, TBP, TCP and TDCP caused disorders in fertility and/or fetal development of animals. Adverse effects on reproduction in humans may be caused by TPP, TCP, and TDCP. In laboratory animals the development of tumors was observed after high doses of TEHP, TCEP, TBP and TDCP. None of these compounds is classified as a human carcinogen. The environmental toxicity of phosphate FRs is low (except for TPP, TCEP and TBEP. They are not stable compounds, in living organisms they are metabolised and quickly excreted. Therefore, they can be used as an alternative to PBDEs. Med. Pr. 2015;66(2:235–264

  7. Development of flame retardant cotton fabric based on ionic liquids via sol-gel technique.

    Science.gov (United States)

    Bentis, A.; Boukhriss, A.; Boyer, D.; Gmouh, S.

    2017-10-01

    In this study, flame retardant cotton fabrics were developed by the sol-gel method, in order to enhance their flame retardant proprieties. For this aim, seven sols were prepared using tetraethylorthosilicate (TEOS) and different ionic liquids (ILs) consist on pyridinium and Methylimidazolium cations with different anions such as: PF6-, CH3COO-, and Br-. Those sols were applied separately to the cotton fabrics by a pad-dry-cure process. The flame retardant properties of functionalized cotton fabrics before and after washing were determined by the vertical flame tests according to ISO6940:2004(F) standard. The effects of anions have been thoroughly investigated, aiming at the optimization of the targeted properties. Thermogravimetric and mechanical according to NF EN ISO 13934-1:2013standard, analyses have been also investigated. The results showed that flame retardancy, thermal stability and mechanical properties of treated fabrics were enhanced by using ionic liquids.

  8. Developmental neurotoxicity of organophosphate flame retardants in early life stages of Japanese medaka (Oryzias latipes).

    Science.gov (United States)

    Sun, Liwei; Tan, Hana; Peng, Tao; Wang, Sisi; Xu, Wenbin; Qian, Haifeng; Jin, Yuanxiang; Fu, Zhengwei

    2016-12-01

    Because brominated flame retardants are being banned or phased out worldwide, organophosphate flame retardants have been used as alternatives on a large scale and have thus become ubiquitous environmental contaminants; this raises great concerns about their environmental health risk and toxicity. Considering that previous research has identified the nervous system as a sensitive target, Japanese medaka were used as an aquatic organism model to evaluate the developmental neurotoxicity of 4 organophosphate flame retardants: triphenyl phosphate, tri-n-butyl phosphate, tris(2-butoxyethyl) phosphate, and tris(2-chloroethyl) phosphate (TCEP). The embryo toxicity test showed that organophosphate flame retardant exposure could decrease hatchability, delay time to hatching, increase the occurrence of malformations, reduce body length, and slow heart rate. Regarding locomotor behavior, exposure to the tested organophosphate flame retardants (except TCEP) for 96 h resulted in hypoactivity for medaka larvae in both the free-swimming and the dark-to-light photoperiod stimulation test. Changes of acetylcholinesterase activity and transcriptional responses of genes related to the nervous system likely provide a reasonable explanation for the neurobehavioral disruption. Overall, the present study clearly demonstrates the developmental neurotoxicity of various organophosphate flame retardants with very different potency and contribute to the determination of which organophosphate flame retardants are appropriate substitutes, as well as the consideration of whether regulations are reasonable and required. Environ Toxicol Chem 2016;35:2931-2940. © 2016 SETAC. © 2016 SETAC.

  9. Aluminum hypophosphite microencapsulated to improve its safety and application to flame retardant polyamide 6

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Hua [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026 (China); Tang, Gang [School of Architecture and Civil Engineering, Anhui University of Technology, 59 Hudong Road, Ma’anshan, Anhui 243002 (China); Hu, Wei-Zhao; Wang, Bi-Bo; Pan, Ying [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026 (China); Song, Lei, E-mail: leisong@ustc.edu.cn [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026 (China); Hu, Yuan, E-mail: yuanhu@ustc.edu.cn [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026 (China); Suzhou Key Laboratory of Urban Public Safety, Suzhou Institute for Advanced Study, University of Science and Technology of China, 166 Ren’ai Road, Suzhou, Jiangsu 215123 (China)

    2015-08-30

    Highlights: • MCAHP was prepared and applied in polyamide 6. • MCA as the capsule material can improve the fire safety of AHP. • Flame retardant polyamide 6 composites with MCAHP show good flame retardancy. - Abstract: Aluminum hypophosphite (AHP) is an effective phosphorus-containing flame retardant. But AHP also has fire risk that it will decompose and release phosphine which is spontaneously flammable in air and even can form explosive mixtures with air in extreme cases. In this paper, AHP has been microencapsulated by melamine cyanurate (MCA) to prepare microencapsulated aluminum hypophosphite (MCAHP) with the aim of enhancing the fire safety in the procedure of production, storage and use. Meanwhile, MCA was a nitrogen-containing flame retardant that can work with AHP via the nitrogen-phosphorus synergistic effect to show improved flame-retardant property than other capsule materials. After microencapsulation, MCA presented as a protection layer inhibit the degradation of AHP and postpone the generation of phosphine. Furthermore, the phosphine concentration could be effectively diluted by inert decomposition products of MCA. These nonflammable decomposition products of MCA could separate phosphine from air delay the oxidizing reaction with oxygen and decrease the heat release rate, which imply that the fire safety of AHP has been improved. Furthermore, MCAHP was added into polyamide 6 to prepare flame retardant polyamide 6 composites (FR-PA6) which show good flame retardancy.

  10. Aluminum hypophosphite microencapsulated to improve its safety and application to flame retardant polyamide 6

    International Nuclear Information System (INIS)

    Ge, Hua; Tang, Gang; Hu, Wei-Zhao; Wang, Bi-Bo; Pan, Ying; Song, Lei; Hu, Yuan

    2015-01-01

    Highlights: • MCAHP was prepared and applied in polyamide 6. • MCA as the capsule material can improve the fire safety of AHP. • Flame retardant polyamide 6 composites with MCAHP show good flame retardancy. - Abstract: Aluminum hypophosphite (AHP) is an effective phosphorus-containing flame retardant. But AHP also has fire risk that it will decompose and release phosphine which is spontaneously flammable in air and even can form explosive mixtures with air in extreme cases. In this paper, AHP has been microencapsulated by melamine cyanurate (MCA) to prepare microencapsulated aluminum hypophosphite (MCAHP) with the aim of enhancing the fire safety in the procedure of production, storage and use. Meanwhile, MCA was a nitrogen-containing flame retardant that can work with AHP via the nitrogen-phosphorus synergistic effect to show improved flame-retardant property than other capsule materials. After microencapsulation, MCA presented as a protection layer inhibit the degradation of AHP and postpone the generation of phosphine. Furthermore, the phosphine concentration could be effectively diluted by inert decomposition products of MCA. These nonflammable decomposition products of MCA could separate phosphine from air delay the oxidizing reaction with oxygen and decrease the heat release rate, which imply that the fire safety of AHP has been improved. Furthermore, MCAHP was added into polyamide 6 to prepare flame retardant polyamide 6 composites (FR-PA6) which show good flame retardancy

  11. Phosphorus flame retardants: properties, production, environmental occurrence, toxicity and analysis.

    Science.gov (United States)

    van der Veen, Ike; de Boer, Jacob

    2012-08-01

    Since the ban on some brominated flame retardants (BFRs), phosphorus flame retardants (PFRs), which were responsible for 20% of the flame retardant (FR) consumption in 2006 in Europe, are often proposed as alternatives for BFRs. PFRs can be divided in three main groups, inorganic, organic and halogen containing PFRs. Most of the PFRs have a mechanism of action in the solid phase of burning materials (char formation), but some may also be active in the gas phase. Some PFRs are reactive FRs, which means they are chemically bound to a polymer, whereas others are additive and mixed into the polymer. The focus of this report is limited to the PFRs mentioned in the literature as potential substitutes for BFRs. The physico-chemical properties, applications and production volumes of PFRs are given. Non-halogenated PFRs are often used as plasticisers as well. Limited information is available on the occurrence of PFRs in the environment. For triphenyl phosphate (TPhP), tricresylphosphate (TCP), tris(2-chloroethyl)phosphate (TCEP), tris(chloropropyl)phosphate (TCPP), tris(1,3-dichloro-2-propyl)phosphate (TDCPP), and tetrekis(2-chlorethyl)dichloroisopentyldiphosphate (V6) a number of studies have been performed on their occurrence in air, water and sediment, but limited data were found on their occurrence in biota. Concentrations found for these PFRs in air were up to 47 μg m(-3), in sediment levels up to 24 mg kg(-1) were found, and in surface water concentrations up to 379 ng L(-1). In all these matrices TCPP was dominant. Concentrations found in dust were up to 67 mg kg(-1), with TDCPP being the dominant PFR. PFR concentrations reported were often higher than polybrominated diphenylether (PBDE) concentrations, and the human exposure due to PFR concentrations in indoor air appears to be higher than exposure due to PBDE concentrations in indoor air. Only the Cl-containing PFRs are carcinogenic. Other negative human health effects were found for Cl-containing PFRs as well as

  12. Identification of Flame Retardants in Polyurethane Foam Collected from Baby Products

    Science.gov (United States)

    2011-01-01

    With the phase-out of PentaBDE in 2004, alternative flame retardants are being used in polyurethane foam to meet flammability standards. However, insufficient information is available on the identity of the flame retardants currently in use. Baby products containing polyurethane foam must meet California state furniture flammability standards, which likely affects the use of flame retardants in baby products throughout the U.S. However, it is unclear which products contain flame retardants and at what concentrations. In this study we surveyed baby products containing polyurethane foam to investigate how often flame retardants were used in these products. Information on when the products were purchased and whether they contained a label indicating that the product meets requirements for a California flammability standard were recorded. When possible, we identified the flame retardants being used and their concentrations in the foam. Foam samples collected from 101 commonly used baby products were analyzed. Eighty samples contained an identifiable flame retardant additive, and all but one of these was either chlorinated or brominated. The most common flame retardant detected was tris(1,3-dichloroisopropyl) phosphate (TDCPP; detection frequency 36%), followed by components typically found in the Firemaster550 commercial mixture (detection frequency 17%). Five samples contained PBDE congeners commonly associated with PentaBDE, suggesting products with PentaBDE are still in-use. Two chlorinated organophosphate flame retardants (OPFRs) not previously documented in the environment were also identified, one of which is commercially sold as V6 (detection frequency 15%) and contains tris(2-chloroethyl) phosphate (TCEP) as an impurity. As an addition to this study, we used a portable X-ray fluorescence (XRF) analyzer to estimate the bromine and chlorine content of the foam and investigate whether XRF is a useful method for predicting the presence of halogenated flame

  13. Effects Of Huntite/hydromagnesite On Capacity Of Flame Retardancy, Mechanical And Physical Properties Of Polypropylene

    OpenAIRE

    Zakut, Merve

    2012-01-01

    In this study, in order to increase the flame retardancy of polypropylene, usage of a flame retardant system comprising huntite and hydromagnesite was suggested. Four different commercial grades (U1250, U1253, LH15, H2090) of H/HM mixtures were used. In order to determine the ideal formulation, mixtures of H/HM were added to twin-screw extruder at 30-40-50-60% loading levels. The ratios of used H/HM mixtures on flame retardancy performances and mechanical properties of polypropylene were eval...

  14. Developments in the flame retardant teratment of cotton/polyester blends

    CSIR Research Space (South Africa)

    Black, WA

    1984-06-01

    Full Text Available I was also interested in the development of an effective flame retardant f ~ s h . He commissioned Gay-Lussac to develop such a treatment, and he subsequently achieved a small amount of success with ammonium salts of sulphuric, hydrochloric and phosphoric... of flame retarding cotton and polyester textiles, is that it is a large complex field of chemistry which has grown enormously over the years. This has resulted i~ the publication of numerous books and reviews on the flame retardancy of cotton...

  15. Identification of flame retardants in polyurethane foam collected from baby products.

    Science.gov (United States)

    Stapleton, Heather M; Klosterhaus, Susan; Keller, Alex; Ferguson, P Lee; van Bergen, Saskia; Cooper, Ellen; Webster, Thomas F; Blum, Arlene

    2011-06-15

    With the phase-out of PentaBDE in 2004, alternative flame retardants are being used in polyurethane foam to meet flammability standards. However, insufficient information is available on the identity of the flame retardants currently in use. Baby products containing polyurethane foam must meet California state furniture flammability standards, which likely affects the use of flame retardants in baby products throughout the U.S. However, it is unclear which products contain flame retardants and at what concentrations. In this study we surveyed baby products containing polyurethane foam to investigate how often flame retardants were used in these products. Information on when the products were purchased and whether they contained a label indicating that the product meets requirements for a California flammability standard were recorded. When possible, we identified the flame retardants being used and their concentrations in the foam. Foam samples collected from 101 commonly used baby products were analyzed. Eighty samples contained an identifiable flame retardant additive, and all but one of these was either chlorinated or brominated. The most common flame retardant detected was tris(1,3-dichloroisopropyl) phosphate (TDCPP; detection frequency 36%), followed by components typically found in the Firemaster550 commercial mixture (detection frequency 17%). Five samples contained PBDE congeners commonly associated with PentaBDE, suggesting products with PentaBDE are still in-use. Two chlorinated organophosphate flame retardants (OPFRs) not previously documented in the environment were also identified, one of which is commercially sold as V6 (detection frequency 15%) and contains tris(2-chloroethyl) phosphate (TCEP) as an impurity. As an addition to this study, we used a portable X-ray fluorescence (XRF) analyzer to estimate the bromine and chlorine content of the foam and investigate whether XRF is a useful method for predicting the presence of halogenated flame

  16. Synergistic effect of a novel triazine charring agent and ammonium polyphosphate on the flame retardant properties of halogen-free flame retardant polypropylene composites

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Caimin; Liang, Minyi; Jiang, Jiali; Huang, Jianguang, E-mail: hjguang@139.com; Liu, Hongbo, E-mail: 962651061@qq.com

    2016-03-20

    Highlights: • A novel triazine charring agent was prepared, and the synergistic effect has been studied between APP and novel charring agent. • The novel IFR system presents excellent flame retardant properties and smoke suppression ability. • The flame retardant mechanism shows that it has high graphitization degree and good shield properties of the char layer. - Abstract: A novel triazine charring agent poly(4,6-dichloro-N-butyl-1,3,5-triazin-2-amine-ethylenediamine) (CNCD-DA) was synthesized, which had good thermal stability and char-forming ability. The synergistic effects between ammonium polyphosphate (APP) and CNCD-DA on flame retardant properties and mechanism of polypropylene (PP) were investigated by the limited oxygen index (LOI), vertical burning test (UL-94), cone calorimeter test (CCT), scanning electron microscopy (SEM), laser Raman spectroscopy analysis (LRS), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The results illustrated when the mass ratio of APP to CNCD-DA was 3:1 with 30% loading, the intumescent flame retardant (IFR) showed the best synergistic effect with LOI value reaching 36.5%, and the IFR could greatly suppress the generation of the flame and smoke during combustion. The results from SEM, TGA, LRS and FTIR indicated that during the combustion IFR could form a continuous and intumescent char containing P−O−P and P−O−C crosslinking structures and polyaromatic structures, thus effectively retard the combustion of PP.

  17. Detection of halogenated flame retardants in polyurethane foam by particle induced X-ray emission

    Science.gov (United States)

    Maley, Adam M.; Falk, Kyle A.; Hoover, Luke; Earlywine, Elly B.; Seymour, Michael D.; DeYoung, Paul A.; Blum, Arlene; Stapleton, Heather M.; Peaslee, Graham F.

    2015-09-01

    A novel application of particle-induced X-ray emission (PIXE) has been developed to detect the presence of chlorinated and brominated flame retardant chemicals in polyurethane foams. Traditional Gas Chromatography-Mass Spectrometry (GC-MS) methods for the detection and identification of halogenated flame retardants in foams require extensive sample preparation and data acquisition time. The elemental analysis of the halogens in polyurethane foam performed by PIXE offers the opportunity to identify the presence of halogenated flame retardants in a fraction of the time and sample preparation cost. Through comparative GC-MS and PIXE analysis of 215 foam samples, excellent agreement between the two methods was obtained. These results suggest that PIXE could be an ideal rapid screening method for the presence of chlorinated and brominated flame retardants in polyurethane foams.

  18. Preparation and Characterization of Flame Retardant PET Fiber with Microencapsulated CMSs/PET

    Directory of Open Access Journals (Sweden)

    NIU Mei

    2016-06-01

    Full Text Available The core-shell carbon microspheres(CMSs/polyethylene terephthalate(PET capsule (PCMSs by in situ polymerization was selected as flame retardant. The flame-retardant PCMSs/PET functional fiber was prepared by melt spinning method. The structure and properties of PET fiber with different mass fractions of flame retardant were characterized by SEM, sound velocimeter, tensile tester and limit oxygen index apparatus. The results show that PCMSs has a good compatibility and dispersion within PET matrix, and the excellent moisture absorption and flame retardant properties of functional PET fiber with smooth surface is obtained when the mass fraction of PCMSs is 0.6%, but the mechanical property of PCMSs/PET fiber with 0.6% PCMSs is a little lower than the PCMSs/PET fiber with 0.2% PCMSs.

  19. Developmental Exposure to Organophosphate Flame Retardants Elicits Overt Toxicity and Alters Behavior in Zebrafish (Danio rerio)

    Science.gov (United States)

    Organophosphate flame retardants (OPFRs) are common replacements for the phased-out polybrominated diphenyl ethers (PBDEs) and have been detected at high concentrations in environmental samples. OPFRs are structurally similar to organophosphate pesticides and may adversely affect...

  20. Potent competitive interactions of some brominated flame retardants and related compounds with human transthyretin in vitro

    NARCIS (Netherlands)

    Meerts, I.A.T.M.; Zanden, van J.J.; Luijks, E.A.C.; Leeuwen-Bol, van I.; Marsh, G.; Jakobsson, E.; Bergman, A.; Brouwer, A.

    2000-01-01

    Brominated flame retardants such as polybrominated diphenyl ethers (PBDEs), pentabromophenol (PBP), and tetrabromobisphenol A (TBBPA) are produced in large quantities for use in electronic equipment, plastics, and building materials. Because these compounds have some structural resemblance to the

  1. Migration of Organophosphate Flame Retardants from Closed Cell Foam to Settled Dust

    Science.gov (United States)

    Many industrial and consumer products, such as electrical and electronic products, furniture, plastics, textile, and building materials are manufactured with organophosphorus flame retardants (OPFRs). OPFRs can leach or diffuse out of the products and are released to the surround...

  2. Migration of Organophorus Flame Retardants From Closed cell form to Settled Dust

    Science.gov (United States)

    Many industrial and consumer products, such as electrical and electronic products, furniture, plastics, textile, and building materials are manufactured with organophosphorus flame retardants (OPFRs). OPFRs can leach or diffuse out of the products and are released to the surround...

  3. Levels and trends of brominated flame retardants in the European environment

    NARCIS (Netherlands)

    Law, R.J.; Allchin, C.R.; Boer, de J.; Covaci, A.; Herzke, D.; Lepom, P.; Morris, S.; Tronczynski, J.; Wit, de C.A.

    2006-01-01

    In this paper, we review those data which have recently become available for brominated flame retardants (particularly the brominated diphenyl ethers (BDEs) and hexabromocyclododecane (HBCD)) in samples from the European environment. Environmental compartments studied comprise the atmosphere,

  4. Synergistic effect of iron and intumescent flame retardant on shape-stabilized phase change material

    International Nuclear Information System (INIS)

    Zhang Ping; Hu Yuan; Song Lei; Lu Hongdian; Wang Jian; Liu Qingqing

    2009-01-01

    This paper deals with the preparation of paraffin/high density polyethylene (HDPE)/intumescent flame retardant (IFR)/iron as flame retardant shape-stabilized phase change material (FSPCM). The influences of iron for FSPCM on morphology, flammability property, latent heat and thermal conductive property were characterized by scanning electron microscopy (SEM), cone calorimeter, differential scanning calorimetry (DSC) and hot disk thermal constants analyser. It was found that iron could be well dispersed into the composite formed by HDPE and paraffin; the flame retardant efficiency of IFR could be improved by adding iron; the thermal conductivity of FSPCM could be increased due to the high thermal conductivity of iron. At the same time, the possible flame retardant mechanism for paraffin/HDPE/IFR with iron as a FSPCM was proposed

  5. Fish energy budget under ocean warming and flame retardant exposure.

    Science.gov (United States)

    Anacleto, Patrícia; Figueiredo, Cátia; Baptista, Miguel; Maulvault, Ana Luísa; Camacho, Carolina; Pousão-Ferreira, Pedro; Valente, Luísa M P; Marques, António; Rosa, Rui

    2018-02-28

    Climate change and chemical contamination are global environmental threats of growing concern for the scientific community and regulatory authorities. Yet, the impacts and interactions of both stressors (particularly ocean warming and emerging chemical contaminants) on physiological responses of marine organisms remain unclear and still require further understanding. Within this context, the main goal of this study was to assess, for the first time, the effects of warming (+ 5 °C) and accumulation of a polybrominated diphenyl ether congener (BDE-209, brominated flame retardant) through dietary exposure on energy budget of the juvenile white seabream (Diplodus sargus). Specifically, growth (G), routine metabolism (R), excretion (faecal, F and nitrogenous losses, U) and food consumption (C) were calculated to obtain the energy budget. The results demonstrated that the energy proportion spent for G dominated the mode of the energy allocation of juvenile white seabream (56.0-67.8%), especially under the combined effect of warming plus BDE-209 exposure. Under all treatments, the energy channelled for R varied around 26% and a much smaller percentage was channelled for excretion (F: 4.3-16.0% and U: 2.3-3.3%). An opposite trend to G was observed to F, where the highest percentage (16.0 ± 0.9%) was found under control temperature and BDE-209 exposure via diet. In general, the parameters were significantly affected by increased temperature and flame retardant exposure, where higher levels occurred for: i) wet weight, relative growth rate, protein and ash contents under warming conditions, ii) only for O:N ratio under BDE-209 exposure via diet, and iii) for feed efficiency, ammonia excretion rate, routine metabolic rate and assimilation efficiency under the combination of both stressors. On the other hand, decreased viscerosomatic index was observed under warming and lower fat content was observed under the combined effect of both stressors. Overall, under future

  6. House Dust Concentrations of Organophosphate Flame Retardants in Relation to Hormone Levels and Semen Quality Parameters

    OpenAIRE

    Meeker, John D.; Stapleton, Heather M.

    2009-01-01

    Background Organophosphate (OP) compounds, such as tris(1,3-dichloro-2-propyl) phosphate (TDCPP) and triphenyl phosphate (TPP), are commonly used as additive flame retardants and plasticizers in a wide range of materials. Although widespread human exposure to OP flame retardants is likely, there is a lack of human and animal data on potential health effects. Objective We explored relationships of TDCPP and TPP concentrations in house dust with hormone levels and semen quality parameters. Meth...

  7. [Concentration and emission fluxes of halogenated flame retardants in sewage from sewage outlet in Dongjiang River].

    Science.gov (United States)

    Zeng, Yan-Hong; Luo, Xiao-Jun; Sun, Yu-Xin; Yu, Le-Huan; Chen, She-Jun; Mai, Bi-Xian

    2011-10-01

    Fourteen sewage samples from sewage outlets in Dongjiang River were collected. Halogented flame retardants were extracted and purified using dichloromethane and alumina/silica-gel column, respectively. The concentrations of halogenated flame retardants were measured utilizing GC/MS, and the emission fluxes were estimated. Decabromodiphenyl ethane (DBDPE) was the predominant halogenated pollutant (accounting for 64%) in sewage with the concentration ranging from 9.1 ng/L to 990 ng/L. The concentrations of polybrominated biphenyl ether (PBDEs), dominated by BDE209, in the sewage ranged from 6.9 ng/L to 470 ng/L, accounting for 30% of total halogenated flame retardants. The concentrations of other flame retardants, such as dechlorane plus (DP), 1, 2-bis(2, 4, 6-tribromophenoxy) ethane (BTBPE), hexabromobenzene (HBB), and pentabromotoluene (PBT), were ranged within 0.17-23.6, nd-26.3, nd-1.45 and nd-0.45 ng/L, respectively. The concentrations of PBDEs in sewage of Dongjiang River were comparable to those in influent wastewater of sewage treatment plants of Guangzhou, suggesting that the wastewater was discharged directly into Dongjiang River without any treatment. The emission flux of halogenated flame retardants from sewage was 191 kg. Emission from industrial wastewater, contributed to 48%-91% of total emission, was the main source of halogenated flame retardants.

  8. Influence of hydrophobic substance on enhancing washing durability of water soluble flame-retardant coating

    Science.gov (United States)

    Jindasuwan, Sunisa; Sukmanee, Nattinee; Supanpong, Chanida; Suwan, Mantana; Nimittrakoolchai, On-uma; Supothina, Sitthisuntorn

    2013-06-01

    Flame-retardant textiles are used in many consumer products. Among halogen-free flame retardant substances, inorganic flame retardants are mainly based on phosphorus, antimony, aluminum and boron-containing compounds. These coatings are soluble in water and therefore are not subjected to washing. In this study, washing durability of the inorganic flame retardant has been improved by incorporation of the hydrophobic substance to the coating. Composition of the coating which is the flame-retardant, monoammonium phosphate (MAP), and the hydrophobic substances, poly(methylhydrogen siloxane) (PMHS) and poly(dimethyl siloxane) (PDMS)), were varied to find the optimum coating solution. The results of SEM and TGA analysis, as well as the burning and washing tests, revealed that the coating solution consisting of MAP:PMHS:PDMS = 5:2:1 wt.% was the optimum condition. It showed the increased residue on the TGA profile compared to the uncoated sample, and self-extinguish after removal of the ignition source. The flame-retardant property can be maintained after washing, making it feasible for variety of applications.

  9. Flame Retardant Effect of Aerogel and Nanosilica on Engineered Polymers

    Science.gov (United States)

    Williams, Martha K.; Smith, Trent M.; Roberson, Luke B.; Yang, Feng; Nelson, Gordon L.

    2010-01-01

    Aerogels are typically manufactured vIa high temperature and pressure-critical-point drying of a colloidal metal oxide gel filled with solvents. Aerogel materials derived from silica materials represent a structural morphology (amorphous, open-celled nanofoams) rather than a particular chemical constituency. Aerogel is not like conventional foams in that it is a porous material with extreme microporosity and composed of individual features only a few nanometers in length with a highly porous dendriticlike structure. This unique substance has unusual properties such as low thermal conductivity, refractive index and sound suppression; in addition to its exceptional ability to capture fast moving dust. The highly porous nature of the aerogel's structure provides large amounts of surface area per unit weight. For instance, a silica aerogel material with a density of 100 kilograms per cubic meters can have surface areas of around 800 to 1500 square meters per gram depending on the precursors and process utilized to produce it. To take advantage of the unique properties of silica aerogels, especially the ultra light weight and low thermal conductivity, their composites with various engineering polymers were prepared and their flammability was investigated by Cone Calorimetry. The flammability of various polystyrene/silica aerogel nanocomposites were measured. The combination of these nanocomposites with a NASA patented flame retardant SINK were also studied. The results were compared with the base polymer to show the differences between composites with different forms of silica.

  10. Brominated flame retardants in Belgian little owl (Athene noctua) eggs

    Energy Technology Data Exchange (ETDEWEB)

    Jaspers, V.; Covaci, A.; Maervoet, J.; Dauwe, T.; Schepens, P.; Eens, M. [Antwerp Univ. (Belgium)

    2004-09-15

    Since the 1960s, polybrominated diphenylethers (PBDEs), a class of brominated flame retardants (BFRs), are widely used in textiles, plastics, electronic equipment and other materials. Their massive use has led to the ubiquitous presence of PBDEs in the environment and in biota in which the PBDE levels seem to increase rapidly. High concentrations of some congeners may cause adverse effects in both wildlife and in human populations1 and this has led to the growing concern of scientists over the last decade and to the need for more data on environmental levels of PBDEs. The little owl (Athene noctua) is a small sedentary predator, which makes it a very suitable biomonitoring species. This owl species feeds on a variety of preys, including small mammals and birds, reptiles, amphibians, earthworms and beetles, depending on the season and the local circumstances. Because very limited information is available about contamination levels in the little owl, a study was conducted to determine the concentrations of PBDEs, polybrominated biphenyls (PBBs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in deserted or addled eggs of little owls in Belgium. Eggs have been used successfully as a monitoring tool for persistent organic pollutants (POPs) in several studies. Although the analysis of POPs in deserted or addled eggs has clear limitations, these can be partially avoided by analysing only highly persistent components, for which the original composition will not change due to 'posthatching' microbiological degradation.

  11. Occurrence of organophosphate flame retardants in drinking water from China.

    Science.gov (United States)

    Li, Jun; Yu, Nanyang; Zhang, Beibei; Jin, Ling; Li, Meiying; Hu, Mengyang; Zhang, Xiaowei; Wei, Si; Yu, Hongxia

    2014-05-01

    Several organophosphate flame retardants (OPFRs) have been identified as known or suspected carcinogens or neurotoxic substances. Given the potential health risks of these compounds, we conducted a comprehensive survey of nine OPFRs in drinking water in China. We found total concentrations of OPFRs in tap water ranging from 85.1 ng/L to 325 ng/L, and tris(2-butoxyethyl) phosphate (TBEP), triphenyl phosphate (TPP), and tris(2-chloroisopropyl) phosphate (TCPP) were the most common components. Similar OPFR concentrations and profiles were observed in water samples processed through six different waterworks in Nanjing, China. However, boiling affected OPFR levels in drinking water by either increasing (e.g., TBEP) or decreasing (e.g., tributyl phosphate, TBP) concentrations depending on the particular compound and the state of the indoor environment. We also found that bottled water contained many of the same major OPFR compounds with concentrations 10-25% lower than those in tap water, although TBEP contamination in bottled water remained a concern. Finally, we concluded that the risk of ingesting OPFRs through drinking water was not a major health concern for either adults or children in China. Nevertheless, drinking water ingestion represents an important exposure pathway for OPFRs. Copyright © 2014. Published by Elsevier Ltd.

  12. Brominated flame retardants in Canadian chicken egg yolks.

    Science.gov (United States)

    Rawn, D F K; Sadler, A; Quade, S C; Sun, W-F; Lau, B P-Y; Kosarac, I; Hayward, S; Ryan, J J

    2011-06-01

    Chicken eggs categorised as conventional, omega-3 enriched, free range and organic were collected at grading stations in three regions of Canada between 2005 and 2006. Free run eggs, which were only available for collection from two regions, were also sampled during this time frame. Egg yolks from each of these egg types (n = 162) were analysed to determine brominated flame retardant levels, specifically polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD). PBDEs were detected in 100% of the 162 samples tested, while HBCD was observed in 85% of the egg yolks. Total PBDE concentrations in egg yolks ranged from 0.018 to 20.9 ng g(-1) lipid (median = 3.03 ng g(-1) lipid), with PBDE 209 identified as being the major contributor to ΣPBDE concentrations. In addition to PBDE 209, PBDE 99, 47, 100, 183 and 153 were important contributors to ΣPBDE concentrations. Total HBCD concentrations ranged from below the limit of detection to a maximum concentration of 71.9 ng g(-1) lipid (median = 0.053 ng g(-1) lipid). The α-isomer was the dominant contributor to ΣHBCD levels in Canadian egg yolks and was the most frequently detected HBCD isomer. ΣPBDE levels exhibited large differences in variability between combinations of region and type. ΣHBCD concentrations were not significantly different among regions, although differences were observed between the different types of egg yolks analysed in the present study.

  13. Sorption of Organophosphorus Flame-Retardants on Settled ...

    Science.gov (United States)

    Dust is an important sink for indoor air pollutants, such as organophosphorus flame-retardants (OPFRs) that are used as additives in industrial and consumer products including electrical and electronic products, furniture, plastics, textile, and building/construction materials. This research investigated the sorption of OPFRs, tris(2-chloroethyl) phosphate (TCEP), tris(1-chlor-2-propyl) phosphate (TCPP), and tris(1,3-dichloro-2-propyl) phosphate (TDCPP) on settled Arizona Test Dust (ATD) using a dual small chamber system. During the test, seven free film release paper dust trays covered with ATD were placed in the sink test chamber. Constant gas phase OPFRs from the source chamber were dosed into the test chamber. The dust evenly spread on each dust tray was removed from the test chamber at different exposure times to determine the amount of OPFRs absorbed by the dust. The ATD has been characterized for a nominal particle size and surface area. The mass of dust on each of seven dust trays was weighed before the dust was placed inside the sink chamber. OPFRs concentrations at the inlet and faceplate of the test chamber were monitored by collecting polyurethane foam (PUF) samples. The OPFR exposed dust and PUF samples were extracted by 1:1 ethyl acetate/methylene chloride and analyzed on GC/MS. The data were used to calculate the OPFR sorption concentration on the dust through dust/air partition. Settled dust can adsorb OPFR from air. The sorption concentration wa

  14. Recent Developments in Organophosphorus Flame Retardants Containing P-C Bond and Their Applications

    Directory of Open Access Journals (Sweden)

    Sophie Wendels

    2017-07-01

    Full Text Available Organophosphorus compounds containing P-C bonds are increasingly developed as flame retardant additives due to their excellent thermal and hydrolytic stability and ease of synthesis. The latest development (since 2010 in organophosphorus flame retardants containing P-C bonds summarized in this review. In this review, we have broadly classified such phosphorus compounds based on the carbon unit linked to the phosphorus atom i.e., could be a part of either an aliphatic or an aromatic unit. We have only considered those published literature where a P-C bond was created as a part of synthetic strategy to make either an intermediate or a final organophosphorus compound with an aim to use it as a flame retardant. General synthetic strategies to create P-C bonds are briefly discussed. Most popular synthetic strategies used for developing P-C containing phosphorus based flame retardants include Michael addition, Michaelis–Arbuzov, Friedels–Crafts and Grignard reactions. In general, most flame retardant derivatives discussed in this review have been prepared via a one- to two-step synthetic strategy with relatively high yields greater than 80%. Specific examples of P-C containing flame retardants synthesized via suitable synthetic strategy and their applications on various polymer systems are described in detail. Aliphatic phosphorus compounds being liquids or low melting solids are generally applied in polymers via coatings (cellulose or are incorporated in the bulk of the polymers (epoxy, polyurethanes during their polymerization as reactive or non-reactive additives. Substituents on the P atoms and the chemistry of the polymer matrix greatly influence the flame retardant behavior of these compounds (condensed phase vs. the gas phase. Recently, aromatic DOPO based phosphinate flame retardants have been developed with relatively higher thermal stabilities (>250 °C. Such compounds have potential as flame retardants for high temperature processable

  15. Flame-retardant-wrapped polyphosphazene nanotubes: A novel strategy for enhancing the flame retardancy and smoke toxicity suppression of epoxy resins.

    Science.gov (United States)

    Qiu, Shuilai; Wang, Xin; Yu, Bin; Feng, Xiaming; Mu, Xiaowei; Yuen, Richard K K; Hu, Yuan

    2017-03-05

    The structure of polyphosphazene nanotubes (PZS) is similar to that of carbon nanotubes (CNTs) before modification. For applications of CNTs in polymer composites, surface wrapping is an economically attractive route to achieve functionalized nanotubes. Based on this idea, functionalized polyphosphazene nanotubes (FR@PZS) wrapped with a cross-linked DOPO-based flame retardant (FR) were synthesized via one-step strategy and well characterized. Then, the obtained FR@PZS was introduced into epoxy resin (EP) to investigate flame retardancy and smoke toxicity suppression performance. Thermogravimetric analysis indicated that FR@PZS significantly enhanced the thermal stability of EP composites. Cone calorimeter results revealed that incorporation of FR@PZS obviously improved flame retardant performance of EP, for example, 46.0% decrease in peak heat release rate and 27.1% reduction in total heat release were observed in the case of epoxy composite with 3wt% FR@PZS. The evolution of toxic CO and other volatile products from the EP decomposition was significantly suppressed after the introduction of FR@PZS, Therefore, the smoke toxicity associates with burning EP was reduced. The presence of both PZS and a DOPO-based flame retardant was probably responsible for this substantial diminishment of fire hazard. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Flame retardation of cellulose-rich fabrics via a simplified layer-by-layer assembly.

    Science.gov (United States)

    Yang, Jun-Chi; Liao, Wang; Deng, Shi-Bi; Cao, Zhi-Jie; Wang, Yu-Zhong

    2016-10-20

    Due to the high cellulose content of cotton (88.0-96.5%), the flame retardation of cotton fabrics can be achieved via an approach for the flame retardation of cellulose. In this work, a facile water-based flame retardant coating was deposited on cotton fabrics by a 'simplified' layer-by-layer (LbL) assembly. The novel coating solution was based on a mild reaction between ammonium polyphosphate (APP) and branched polyethyleneimine (BPEI), and the reaction mechanism was studied. TGA results showed that the char residues of coated fabrics were remarkably increased. The fabric with only 5wt% coating showed self-extinguishing in the horizontal flame test, and the peak heat release rate (pHRR) in cone calorimeter test decreased by 51%. Furthermore, this coating overcame a general drawback of flame-retardant LbL assembly which was easily washed away. Therefore, the simplified LbL method provides a fast, low-cost, eco-friendly and wash-durable flame-retardant finishing for the cellulose-rich cotton fabrics. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. An Overview of Mode of Action and Analytical Methods for Evaluation of Gas Phase Activities of Flame Retardants

    Directory of Open Access Journals (Sweden)

    Khalifah A. Salmeia

    2015-03-01

    Full Text Available The latest techniques used to prove, describe and analyze the gas phase activity of a fire retardant used in polymeric materials are briefly reviewed. Classical techniques, such as thermogravimetric analysis or microscale combustion calorimetry, as well as complex and advanced analytical techniques, such as modified microscale combustion calorimeter (MCC, molecular beam mass spectroscopy and vacuum ultra violet (VUV photoionization spectroscopy coupled with time of flight MS (TOF-MS, are described in this review. The recent advances in analytical techniques help not only in determining the gas phase activity of the flame-retardants but also identify possible reactive species responsible for gas phase flame inhibition. The complete understanding of the decomposition pathways and the flame retardant activity of a flame retardant system is essential for the development of new eco-friendly-tailored flame retardant molecules with high flame retardant efficiency.

  18. Acid-base synergistic flame retardant wood pulp paper with high thermal stability.

    Science.gov (United States)

    Wang, Ning; Liu, Yuansen; Xu, Changan; Liu, Yuan; Wang, Qi

    2017-12-15

    Acid-catalytic degradation caused by acid source flame retardants is the main reason for a decline in thermal stability of flame-retarded lignocellulosic materials. In the present research, a guanidine phosphate (GP)/borax (BX) flame retardant system based on acid-base synergistic interaction was designed and used in wood pulp paper (WPP) to solve this problem. Results showed that the treated WPP obtained good flame retardancy with a limiting oxygen index (LOI) value of 35.7%. As a basic flame retardant, borax could chemically combine with the acids released by guanidine phosphate, thus decreasing the acidity of the system in the initial heating stage. In this way, acid-catalytic degradation is greatly retarded on the lignocelluloses to improve thermal stability (the temperature of maximum degradation peak from 286°C to 314°C). Meanwhile, borax was also advantageous to form a denser and firmer condensed phase through reinforcement of the acid-base reaction product, borophosphates, allowing it to provide a protective barrier with higher quality. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Synthesis and Application of a Novel Polyamide Charring Agent for Halogen-Free Flame Retardant Polypropylene

    Directory of Open Access Journals (Sweden)

    Jie Liu

    2013-01-01

    Full Text Available A novel charring agent, poly(p-ethylene terephthalamide (PETA, for halogen-free flame retardant polypropylene was synthesized by using p-phthaloyl chloride (TPC and ethylenediamine through solution polycondensation at low temperature, and the effects of PETA on flame retardance of polypropylene (PP/IFR systems were studied. The experimental results showed that PETA could considerably enhance the fire retardant performance as proved by evidence of the increase of limiting oxygen index (LOI values, the results of UL-94 tests, and cone calorimeter tests (CCT. Fourier transform infrared spectroscopy (FTIR and scanning electron microscope (SEM demonstrated that an appropriate amount of PETA could react with PP/IFR system to form cross-link network; a more compact char layer could be formed which was responsible for the improved thermal and flame retardant properties of PP/IFR systems. However, the superfluous amount of PETA would play the negative role.

  20. Flame retardant transfers from U.S. households (dust and laundry wastewater) to the aquatic environment.

    Science.gov (United States)

    Schreder, Erika D; La Guardia, Mark J

    2014-10-07

    Levels of flame retardants in house dust and a transport pathway from homes to the outdoor environment were investigated in communities near the Columbia River in Washington state (WA). Residential house dust and laundry wastewater were collected from 20 homes in Vancouver and Longview, WA and analyzed for a suite of flame retardants to test the hypothesis that dust collecting on clothing and transferring to laundry water is a source of flame retardants to wastewater treatment plants (WWTPs) and subsequently to waterways. Influent and effluent from two WWTPs servicing these communities were also analyzed for flame retardants. A total of 21 compounds were detected in house dust, including polybrominated diphenyl ethers (PBDEs), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB or EH-TBB), bis(2-ethylhexyl) 3,4,5,6-tetrabromophthalate (TBPH), 1,2-bis(2,4,6,-tribromophenoxy)ethane (BTBPE) and decabromodiphenylethane (DBDPE), hexabromocyclododecane (HBCD or HBCDD), tetrabromobisphenol A (TBBPA), and three chlorinated organophosphate flame retardants (ClOPFRs), tris(1,3-dichloro-2-propyl)phosphate (TDCPP or TDCIPP), tris(1-chloro-2-propyl)phosphate (TCPP or TCIPP), and tris(2-chloroethyl)phosphate (TCEP). Levels ranged from 3.6 to 82,700 ng g(-1) (dry weight). Of the 21 compounds detected in dust, 18 were also detected in laundry wastewater. Levels ranged from 47.1 to 561,000 ng L(-1). ClOPFRs were present at the highest concentrations in both dust and laundry wastewater, making up 72% of total flame retardant mass in dust and 92% in laundry wastewater. Comparison of flame retardant levels in WWTP influents to estimates based on laundry wastewater levels indicated that laundry wastewater may be the primary source to these WWTPs. Mass loadings to the Columbia River from each treatment plant were by far the highest for the ClOPFRs and ranged up to 114 kg/yr for TCPP.

  1. Flame retardant associations between children's handwipes and house dust.

    Science.gov (United States)

    Stapleton, Heather M; Misenheimer, John; Hoffman, Kate; Webster, Thomas F

    2014-12-01

    Polybrominated diphenyl ether (PBDE), flame retardants (FRs) have been ubiquitously detected at high concentrations in indoor environments; however, with their recent phase-out, more attention is being focused on measurements of exposure to alternative FRs such as organophosphate FRs (OPFRs). In our previous research, we found that PBDE residues measured on children's handwipes were a strong predictor of serum PBDE levels. Here we build upon this research to examine longitudinal changes in PBDEs in indoor dust and children's handwipes, and explore the associations between handwipes and dust for alternative FRs. Children from our previous study were re-contacted after approximately two years and new samples of indoor dust and handwipes were collected. PBDE dust-levels were significantly correlated between two different sampling rounds separated by two years; however, PBDE levels in handwipes were not correlated, perhaps suggesting that the sources of PBDEs remained relatively constant in the home, but that behavioral differences in children are changing with age and influencing handwipe levels. OPFRs [i.e. tris(1,3-dichloroisopropyl) phosphate (TDCPP), tris(2-chloroethyl) phosphate (TCEP), tris(2-chloroisopropyl) phosphate (TCIPP)], 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB, also known as TBB), di(2-ethylhexyl) tetrabromophthalate (BEH-TEBP, also known as TBPH), and 1,2,5,6,9,10-hexabromocyclododecane (HBCD) were also ubiquitously detected in house dust samples and geometric mean levels were similar to PBDE levels, or higher in the case of the OPFRs. Significant associations between handwipes and house dust were observed for these alternative FRs, particularly for EH-TBB (rs=0.54; p5 times d(-1)) was associated with lower FR levels in handwipes. Overall these data suggest that exposure to these alternative FRs will be similar to PBDE exposure, and the influence of hand-to-mouth behavior in children's exposure needs to be further examined to better estimate

  2. Catalytic degradation of brominated flame retardants by copper oxide nanoparticles.

    Science.gov (United States)

    Yecheskel, Yinon; Dror, Ishai; Berkowitz, Brian

    2013-09-01

    The catalytic degradation of two brominated flame retardants (BFRs), tribromoneopentyl alcohol (TBNPA) and 2,4 dibromophenol (2,4-DBP) by copper oxide nanoparticles (nCuO) was investigated. The degradation kinetics, the debromination, and the formation of intermediates by nCuO catalysis were also compared to Fenton oxidation and nano zero-valent iron (nZVI) reduction methods. BFRs have been added to various products like plastic, textile, electronics and synthetic polymers at growing rates. In spite of the clear advantages of reducing fire damages, many of these BFRs may be released to the environment after their beneficial use and become contaminants. The two studied BFRs were fully degraded with sufficient time (hours to days) and oxidation agent (H2O2). Shorter reaction times showed differences in reaction pathway and kinetics. The 2,4-DBP showed faster degradation than TBNPA, by nCuO catalysis. Relatively high resistance to degradation was recorded for 2,4-DBP with nZVI, yielding 20% degradation after 24h, while the TBNPA was degraded by 85% within 12h. Electron Spin Resonance (ESR) measurements show generation of both hydroxyl and superoxide radicals. In addition, inhibition of 2,4-DBP degradation in the presence of spin traps implies a radical degradation mechanism. A catalytic mechanism for radical generation and BFR degradation by nCuO is proposed. It is further suggested that H2O2 plays an essential role in the activation of the catalyst. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Human health risk associated with brominated flame-retardants (BFRs).

    Science.gov (United States)

    Lyche, Jan L; Rosseland, Carola; Berge, Gunnar; Polder, Anuschka

    2015-01-01

    The purposes of this review are to assess the human exposure and human and experimental evidence for adverse effects of brominated flame-retardants (BFRs) with specific focus on intake from seafood. The leakage of BFRs from consumer products leads to exposure of humans from fetal life to adulthood. Fish and fish products contain the highest levels of BFRs and dominate the dietary intake of frequent fish eaters in Europe, while meat, followed by seafood and dairy products accounted for the highest US dietary intake. House dust is also reported as an important source of exposure for children as well as adults. The levels of BFRs in the general North American populations are higher than those in Europe and Japan and the highest levels are detected in infants and toddlers. The daily intake via breast milk exceeds the RfD in 10% of US infants. BFRs including PBDEs, HBCDs and TBBP-A have induced endocrine-, reproductive- and behavior effects in laboratory animals. Furthermore, recent human epidemiological data demonstrated association between exposure to BFRs and similar adverse effects as observed in animal studies. Fish including farmed fish and crude fish oil for human consumption may contain substantial levels of BFRs and infants and toddlers consuming these products on a daily basis may exceed the tolerable daily intake suggesting that fish and fish oil alone represent a risk to human health. This intake comes in addition to exposure from other sources (breast milk, other food, house dust). Because potential harmful concentrations of BFRs and other toxicants occur in fish and fish products, research on a wider range of products is warranted, to assess health hazard related to the contamination of fish and fish products for human consumption. Copyright © 2014. Published by Elsevier Ltd.

  4. Flame Retardant Fibers for Human Space Exploration - Past, Present, and Future

    Science.gov (United States)

    Orndoff, Evelyne

    2017-01-01

    The National Aeronautics and Space Administration (NASA) has led in the development of unique flame retardant fibers for human spaceflight since the beginning of the Apollo program. After the Apollo 1 fire which killed Command Pilot Virgil I 'Gus' Grissom, Senior Pilot Edward H. White II, and Pilot Roger B. Chaffee from cardiac arrest on January 27, 1967, the accident investigators found severe third degree burns and melted spacesuits on the astronauts bodies. NASA immediately initiated an extensive research program aimed at developing flame retardant and flame resistant fibers for the enriched oxygen atmosphere of the Apollo crew cabin. Fibers are flame retardant when they have been modified by chemical and thermal treatments. Fibers are flame resistant when they are made of inherently flame resistant materials (i.e. glass, ceramic, highly aromatic polymers). Immediately after this tragic accident, NASA funded extensive research in specifically developing flame retardant fibers and fabrics. The early developmental efforts for human spaceflight were for the outer layer of the Apollo spacesuit. It was imperative that non-flammable fabrics be used in a 100% oxygen environment. Owens-Corning thus developed the Beta fiber that was immediately used in the Apollo program and later in the Space Shuttle program. Aside from the urgent need for protective fabrics for the spacesuit, NASA also needed flame retardant fabrics for both clothing and equipment inside the spacecraft. From the mid-1960s to the early 1980's, NASA contracted with many companies to develop inherently flame retardant fibers and flame retardant finishes for existing fibers. Fluorocarbons and aromatic polyamides were the polymers of great interest for the development of new inherently flame retardant fibers for enriched oxygen environments. These enriched environments varied for different space programs. For example, the Apollo program requirements were for materials that would not support combustion in a

  5. Flame-Retardant and Thermal Degradation Mechanism of Caged Phosphate Charring Agent with Melamine Pyrophosphate for Polypropylene

    OpenAIRE

    Lai, Xuejun; Qiu, Jiedong; Li, Hongqiang; Zeng, Xingrong; Tang, Shuang; Chen, Ye; Chen, Zhen

    2015-01-01

    An efficient caged phosphate charring agent named PEPA was synthesized and combined with melamine pyrophosphate (MPP) to flame-retard polypropylene (PP). The effects of MPP/PEPA on the flame retardancy and thermal degradation of PP were investigated by limiting oxygen index (LOI), vertical burning test (UL-94), cone calorimetric test (CCT), and thermogravimetric analysis (TGA). It was found that PEPA showed an outstanding synergistic effect with MPP in flame retardant PP. When the content of ...

  6. -Styrene)

    KAUST Repository

    Sutisna, Burhannudin

    2017-10-04

    Membranes are prepared by self-assembly and casting of 5 and 13 wt% poly(styrene-b-butadiene-b-styrene) (PS-b-PB-b-PS) copolymers solutions in different solvents, followed by immersion in water or ethanol. By controlling the solution-casting gap, porous films of 50 and 1 µm thickness are obtained. A gradient of increasing pore size is generated as the distance from the surface increased. An ordered porous surface layer with continuous nanochannels can be observed. Its formation is investigated, by using time-resolved grazing incident small angle X-ray scattering, electron microscopy, and rheology, suggesting a strong effect of the air-solution interface on the morphology formation. The thin PS-b-PB-b-PS ordered films are modified, by promoting the photolytic addition of thioglycolic acid to the polybutadiene groups, adding chemical functionality and specific transport characteristics on the preformed nanochannels, without sacrificing the membrane morphology. Photomodification increases fivefold the water permeance to around 2 L m(-2) h(-1) bar(-1) , compared to that of the unmodified one. A rejection of 74% is measured for methyl orange in water. The membranes fabrication with tailored nanochannels and chemical functionalities can be demonstrated using relatively lower cost block copolymers. Casting on porous polyacrylonitrile supports makes the membranes even more scalable and competitive in large scale.

  7. Piloted Ignition to Flaming in Smoldering Fire-Retarded Polyurethane Foam

    Science.gov (United States)

    Putzeys, O.; Fernandez-Pello, A. C.; Urban, D. L.

    2007-01-01

    Experimental results are presented on the piloted transition from smoldering to flaming in the fire-retarded polyurethane foam Pyrell . The samples are small rectangular blocks with a square cross section, vertically placed in the wall of a vertical wind tunnel. Three of the vertical sample sides are insulated and the fourth side is exposed to an upward oxidizer flow of variable oxygen concentration and to a variable radiant heat flux. The gases emitted from the smoldering reaction pass upwards through a pilot, which consists of a coiled resistance heating wire. In order to compensate for the solid-phase and gas-phase effects of the fire retardants on the piloted transition from smoldering to flaming in Pyrell, it was necessary to assist the process by increasing the power supplied to the smolder igniter and the pilot (compared to that used for non-fire retarded foam). The experiments indicate that the piloted transition from smoldering to flaming occurs when the gaseous mixture at the pilot passes the lean flammability limit. It was found that increasing the oxygen concentration or the external heat flux increases the likelihood of a piloted transition from smoldering to flaming, and generally decreases the time delay to transition. The piloted transition to flaming is observed in oxygen concentrations of 23% and above in both low-density and high-density Pyrell. Comparisons with previous experiments show that the piloted transition from smoldering to flaming is possible under a wider range of external conditions (i.e. lower oxygen concentration) than the spontaneous transition from smoldering to flaming. The results show that the fire retardants in Pyrell are very effective in preventing the piloted transition to flaming in normal air, but Pyrell is susceptible to smoldering and the piloted transition to flaming in oxygen-enriched environments. Therefore, precautions should be taken in the design of applications of Pyrell in oxygen-enriched environments to reduce

  8. Role of Surface Interactions in the Synergizing Polymer/Clay Flame Retardant Properties

    Energy Technology Data Exchange (ETDEWEB)

    Pack, S.; Kashiwagi, T; Cao, C; Korach, C; Lewin, M; Rafailovich, M

    2010-01-01

    The absorption of resorcinol di(phenyl phosphate) (RDP) oligomers on clay surfaces has been studied in detail and is being proposed as an alternative method for producing functionalized clays for nanocomposite polymers. The ability of these clays to be exfoliated or intercalated in different homopolymers was investigated using both transmission electron microscopy and small-angle X-ray scattering results, compared with contact angle measurements on Langmuir-Blodgett clay monolayers, where the interfacial energies were used as predictors of the polymer/clay interactions. We found that the contact angle between PS/RDP clay monolayer substrates was {approx}2.5{sup o}, whereas the angle for polystyrene (PS)/Cloisite 20A clays substrates was {approx}32{sup o}, consistent with the large degree of exfoliation observed in PS for the RDP-coated clays. The interfacial activity of these clays was also measured, and we found that the RDP-coated clays segregated to the interfaces of PC/poly(styrene-co-acrylonitrile) blends, while they segregated into the poly(methyl methacrylate) (PMMA) domain of PS/PMMA blends. This morphology was explained in terms of the relative energy advantage in placing the RDP versus the Cloisite clays at the interfaces. Finally, we demonstrated the effects of the relative surface energies of the clays in segregating to the blend air interface when heated to high temperatures. The segregation was shown to affect the composition and mechanical properties of the resulting chars, which in turn could determine their flame retardant response.

  9. Biobased polyelectrolyte multilayer-coated hollow mesoporous silica as a green flame retardant for epoxy resin.

    Science.gov (United States)

    Jiang, Shu-Dong; Tang, Gang; Chen, Junmin; Huang, Zheng-Qi; Hu, Yuan

    2018-01-15

    Here, we describe a multifunctional biobased polyelectrolyte multilayer-coated hollow mesoporous silica (HM-SiO 2 @CS@PCL) as a green flame retardant through layer-by-layer assembly using hollow mesoporous silica (HM-SiO 2 ), chitosan (CS) and phosphorylated cellulose (PCL). The electrostatic interactions deposited the CS/PCL coating on the surface of HM-SiO 2 . Subsequently, this multifunctional flame retardant was used to enhance thermal properties and flame retardancy of epoxy resin. The addition of HM-SiO 2 @CS@PCL to the epoxy resin thermally destabilized the epoxy resin composite, but generated a higher char yield. Furthermore, HM-SiO 2 played a critical role and generated synergies with CS and PCL to improve fire safety of the epoxy resin due to the multiple flame retardancy elements (P, N and Si). This multi-element, synergistic, flame-retardant system resulted in a remarkable reduction (51%) of peak heat release rate and a considerable removal of flammable decomposed products. Additionally, the incorporation of HM-SiO 2 @CS@PCL can sustainably recycle the epoxy resin into high value-added hollow carbon spheres during combustion. Therefore, the HM-SiO 2 @CS@PCL system provides a practical possibility for preparing recyclable polymer materials with multi-functions and high performances. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Intrinsic Flame-Retardant and Thermally Stable Epoxy Endowed by a Highly Efficient, Multifunctional Curing Agent

    Directory of Open Access Journals (Sweden)

    Chunlei Dong

    2016-12-01

    Full Text Available It is difficult to realize flame retardancy of epoxy without suffering much detriment in thermal stability. To solve the problem, a super-efficient phosphorus-nitrogen-containing reactive-type flame retardant, 10-(hydroxy(4-hydroxyphenylmethyl-5,10-dihydrophenophosphazinine-10-oxide (HB-DPPA is synthesized and characterized. When it is used as a co-curing agent of 4,4′-methylenedianiline (DDM for curing diglycidyl ether of bisphenol A (DGEBA, the cured epoxy achieves UL-94 V-0 rating with the limiting oxygen index of 29.3%. In this case, the phosphorus content in the system is exceptionally low (0.18 wt %. To the best of our knowledge, it currently has the highest efficiency among similar epoxy systems. Such excellent flame retardancy originates from the exclusive chemical structure of the phenophosphazine moiety, in which the phosphorus element is stabilized by the two adjacent aromatic rings. The action in the condensed phase is enhanced and followed by pressurization of the pyrolytic gases that induces the blowing-out effect during combustion. The cone calorimeter result reveals the formation of a unique intumescent char structure with five discernible layers. Owing to the super-efficient flame retardancy and the rigid molecular structure of HB-DPPA, the flame-retardant epoxy acquires high thermal stability and its initial decomposition temperature only decreases by 4.6 °C as compared with the unmodified one.

  11. Flame retardant finishing of cotton fabric based on synergistic compounds containing boron and nitrogen.

    Science.gov (United States)

    Xie, Kongliang; Gao, Aiqin; Zhang, Yongsheng

    2013-10-15

    Boric acid and compound containing nitrogen, 2,4,6-tri[(2-hydroxy-3-trimethyl-ammonium)propyl]-1,3,5-triazine chloride (Tri-HTAC) were used to finish cotton fabric. The flame retardant properties of the finished cotton fabrics and the synergetic effects of boron and nitrogen elements were investigated and evaluated by limited oxygen index (LOI) method. The mechanism of cross-linking reaction among cotton fiber, Tri-HTAC, and boric acid was discussed by FTIR and element analysis. The thermal stability and surface morphology of the finished cotton fabrics were investigated by thermogravimetric analysis (TGA) and scanning electron microscope (SEM), respectively. The finishing system of the mixture containing boron and nitrogen showed excellent synergistic flame retardancy for cotton fabric. The cotton fabric finished with mixture system had excellent flame retardancy. The LOI value of the treated cotton fabric increased over 27.5. Tri-HTAC could form covalent bonds with cellulose fiber and boric acid. The flame retardant cotton fabric showed a slight decrease in tensile strength and whiteness. The surface morphology of flame retardant cotton fiber was smooth. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Preparation, characterization of microencapsulated ammonium polyphosphate and its flame retardancy in polyurethane composites

    International Nuclear Information System (INIS)

    Shen, Ming-Yuan; Chen, Wei-Jen; Kuan, Chen-Feng; Kuan, Hsu-Chiang; Yang, Jia-Ming; Chiang, Chin-Lung

    2016-01-01

    In this study, a novel microencapsulated flame retardant containing ammonium polyphosphate (APP) and an 4,4′-oxydianiline-formaldehyde (OF) resin as the core and shell material was synthesized using in situ polymerization technology. The structure and performance of OF microencapsulated APP (OFAPP) were characterized using Fourier transform infrared spectroscopy and scanning electron microscopy. The thermal properties of OFAPP were systematically analyzed through thermogravimetric analysis. Flame retardancy tests, such as limiting oxygen index (LOI) and UL-94, were conducted to evaluate the effect of varying the composition of APP and OFAPP in silanol-terminated polyurethane (Si-PU) composites. The results indicated that the microencapsulation of APP with the OF resin resulted in improved hydrophobicity. The results also revealed that the flame retardancy of the Si-PU/OFAPP composite (LOI = 37%) was higher than that of the Si-PU/APP composite (LOI = 23%) at the same additive loading. - Highlights: • A novel microencapsulated flame retardant was synthesized using in situ polymerization technology. • The microencapsulation of ammonium polyphosphate with the polymer resin resulted in improved hydrophobicity. • Polyurethane composites have excellent thermal stability and flame retardance.

  13. Preparation, characterization of microencapsulated ammonium polyphosphate and its flame retardancy in polyurethane composites

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Ming-Yuan; Chen, Wei-Jen [Department of Aviation Mechanical Engineering, China University of Science and Technology, Hsinchu County, 303, Taiwan (China); Kuan, Chen-Feng; Kuan, Hsu-Chiang [Department of Computer Application Engineering, Far East University, Tainan, 744, Taiwan (China); Yang, Jia-Ming [Green Flame Retardant Material Research Laboratory, Department of Safety, Health and Environmental Engineering, Hung-Kuang University, Taichung, 433, Taiwan (China); Chiang, Chin-Lung, E-mail: dragon@sunrise.hk.edu.tw [Green Flame Retardant Material Research Laboratory, Department of Safety, Health and Environmental Engineering, Hung-Kuang University, Taichung, 433, Taiwan (China)

    2016-04-15

    In this study, a novel microencapsulated flame retardant containing ammonium polyphosphate (APP) and an 4,4′-oxydianiline-formaldehyde (OF) resin as the core and shell material was synthesized using in situ polymerization technology. The structure and performance of OF microencapsulated APP (OFAPP) were characterized using Fourier transform infrared spectroscopy and scanning electron microscopy. The thermal properties of OFAPP were systematically analyzed through thermogravimetric analysis. Flame retardancy tests, such as limiting oxygen index (LOI) and UL-94, were conducted to evaluate the effect of varying the composition of APP and OFAPP in silanol-terminated polyurethane (Si-PU) composites. The results indicated that the microencapsulation of APP with the OF resin resulted in improved hydrophobicity. The results also revealed that the flame retardancy of the Si-PU/OFAPP composite (LOI = 37%) was higher than that of the Si-PU/APP composite (LOI = 23%) at the same additive loading. - Highlights: • A novel microencapsulated flame retardant was synthesized using in situ polymerization technology. • The microencapsulation of ammonium polyphosphate with the polymer resin resulted in improved hydrophobicity. • Polyurethane composites have excellent thermal stability and flame retardance.

  14. A novel reutilization method for waste printed circuit boards as flame retardant and smoke suppressant for poly (vinyl chloride)

    Energy Technology Data Exchange (ETDEWEB)

    Xiu, Fu-Rong, E-mail: xiu_chem@hotmail.com [College of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou 350108 (China); Weng, Huiwei; Qi, Yingying; Yu, Gending; Zhang, Zhigang [College of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou 350108 (China); Zhang, Fu-Shen [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China)

    2016-09-05

    Highlights: • We report a novel electronic waste-based flame retardant for PVC. • The SCWO-treated PCBs significantly improves the flame retardancy of PVC. • The flame retardant mechanism of SCWO-treated PCBs was studied. • Appropriate amount flame retardant does not degrade the mechanical property of PVC. - Abstract: In this study, a novel reutilization method for waste printed circuit boards (PCBs) as flame retardant and smoke suppressant for poly (vinyl chloride) (PVC) was successfully testified. A supercritical water oxidation (SCWO) process was applied to treat waste PCBs before they could be used as flame retardants of PVC. The results indicated that SCWO conditions had a significant effect on the flame retarding and smoke suppressing properties of waste PCBs for PVC. Cu{sub 2}O, CuO, and SnO{sub 2} were the main active ingredients in waste PCBs-derived flame retardants. A conversion of Cu elements (Cu{sup 0} → Cu{sup +} → Cu{sup 2+}) during SCWO process with the increase of reaction temperature was found to be the key influence factor for the flame retarding properties of SCWO-treated PCBs. The experiment results also showed that there was a synergistic effect of flame retardancy between Cu{sup +} and Cu{sup 2+}. After the optimized SCWO treatment, SCWO-treated PCBs significantly improved the flame retardancy and smoke suppression of PVC. Limiting oxygen index (LOI) and char yield (CY) increased with increasing SCWO-treated PCBs content in PVC, while smoke density rating (SDR) and maximum smoke density (MSD) decreased markedly. The mechanical properties of PVC samples were influenced in different degree by adding different content SCWO-treated PCBs.

  15. Halogenated flame retardants: do the fire safety benefits justify the risks?

    Science.gov (United States)

    Shaw, Susan D; Blum, Arlene; Weber, Roland; Kannan, Kurunthachalam; Rich, David; Lucas, Donald; Koshland, Catherine P; Dobraca, Dina; Hanson, Sarah; Birnbaum, Linda S

    2010-01-01

    Since the 1970s, an increasing number of regulations have expanded the use of brominated and chlorinated flame retardants. Many of these chemicals are now recognized as global contaminants and are associated with adverse health effects in animals and humans, including endocrine and thyroid disruption, immunotoxicity, reproductive toxicity, cancer, and adverse effects on fetal and child development and neurologic function. Some flame retardants such as polybrominated diphenyl ethers (PBDEs) have been banned or voluntarily phased out by manufacturers because of their environmental persistence and toxicity, only to be replaced by other organohalogens of unknown toxicity. Despite restrictions on further production in some countries, consumer products previously treated with banned retardants are still in use and continue to release toxic chemicals into the environment, and the worldwide use of organohalogen retardants continues to increase. This paper examines major uses and known toxic effects of commonly-used organohalogen flame retardants, replacements for those that have been phased out, their combustion by-products, and their effectiveness at reducing fire hazard. Policy and other solutions to maintain fire safety while reducing toxicity are suggested. The major conclusions are: (1) Flammability regulations can cause greater adverse environmental and health impacts than fire safety benefits. (2) The current options for end-of-life disposal of products treated with organohalogens retardants are problematic. (3) Life-cycle analyses evaluating benefits and risks should consider the health and environmental effects of the chemicals, as well as their fire safety impacts. (4) Most fire deaths and most fire injuries result from inhaling carbon monoxide, irritant gases, and soot. The incorporation of organohalogens can increase the yield of these toxic by-products during combustion. (5) Fire-safe cigarettes, fire-safe candles, child-resistant lighters, sprinklers, and

  16. Environment-friendly, flame retardant thermoplastic elastomer-magnesium hydroxide composites

    Science.gov (United States)

    Tang, Hao; Chen, Kunfeng; Li, Xiaonan; Ao, Man; Guo, Xinwen; Xue, Dongfeng

    Halogen-free and environment-friendly magnesium hydroxide (Mg(OH)2) was synthesized to enhance the flame retardant properties of thermoplastic elastomer (TPE). When the Mg(OH)2 content was optimized to 35wt.%, the TPE-Mg(OH)2 composites exhibited the best flame retardant properties. The results showed that there was a delay of ignition time of the samples containing Mg(OH)2; compared with the samples without Mg(OH)2, the heat release rate and total heat release decrease by 31.4% and 35.6%, while total smoke production and mass loss rate reduce by 56% and 34.2%, respectively. This work opens a door to manufacture fire-resistant polymer-based composites with environmental-friendly flame retardant additives by controllable crystallization and chemical strategies.

  17. Synergistic effects of iron powder on intumescent flame retardant polypropylene system

    Directory of Open Access Journals (Sweden)

    2009-06-01

    Full Text Available The effects of iron powder as a synergistic agent on the flame retardancy of intumescent flame retardant polypropylene composites (IFR-PP were studied. The thermogravimetric analysis (TGA and cone calorimeter (CONE were used to evaluate the synergistic effects of iron powder (Fe. The TGA data showed that Fe could enhance the thermal stability of the IFR-PP systems at high temperature and effectively increase the char residue formation. The CONE results revealed that Fe and IFR could clearly change the decomposition behavior of PP and form a char layer on the surface of the composites, consequently resulting in efficient reduction of the flammability parameters, such as heat release rate (HRR, mass loss (ML, Mass loss rate (MLR, total heat release (THR, carbon monoxide and so on. Thus, a suitable amount of Fe plays a synergistic effect in the flame retardancy of IFR composites.

  18. Lithium-Ion Electrolytes Containing Flame Retardant Additives for Increased Safety Characteristics

    Science.gov (United States)

    Smart, Marshall C. (Inventor); Smith, Kiah A. (Inventor); Bugga, Ratnakumar V. (Inventor); Prakash, Surya G. (Inventor); Krause, Frederick Charles (Inventor)

    2014-01-01

    The invention discloses various embodiments of Li-ion electrolytes containing flame retardant additives that have delivered good performance over a wide temperature range, good cycle life characteristics, and improved safety characteristics, namely, reduced flammability. In one embodiment of the invention there is provided an electrolyte for use in a lithium-ion electrochemical cell, the electrolyte comprising a mixture of an ethylene carbonate (EC), an ethyl methyl carbonate (EMC), a fluorinated co-solvent, a flame retardant additive, and a lithium salt. In another embodiment of the invention there is provided an electrolyte for use in a lithium-ion electrochemical cell, the electrolyte comprising a mixture of an ethylene carbonate (EC), an ethyl methyl carbonate (EMC), a flame retardant additive, a solid electrolyte interface (SEI) film forming agent, and a lithium salt.

  19. Effect of biochar on mechanical and flame retardant properties of wood - Plastic composites

    Science.gov (United States)

    Zhang, Qingfa; Cai, Hongzhen; Yang, Keyan; Yi, Weiming

    Biochar/wood/plastic composites were prepared with different biochar content by the extrusion method, and the mechanical properties and flame retardant properties were tested. The study indicated that: with the increase of biochar content, the mechanical properties of the composites tended to rise at first and then fell. This suggested that the appropriate amount of biochar can promote the mechanical properties of the biochar/wood/plastic composites. Though both Mg(OH)2 and Al(OH)3 could improve the Flame retardant properties of the material evidently, Mg(OH)2 obtained a better effect than Al(OH)3. In particular, when the adding amount of Mg(OH)2 is 40 wt%, the flame retardant effect is the best. Al(OH)3 can reduce the mechanical properties of the material, while Mg(OH)2 could evidently promote the tensile strength and impact resistance strength of the material.

  20. Thermal oxidative degradation behaviours of flame-retardant thermotropic liquid crystal copolyester/PET blends

    International Nuclear Information System (INIS)

    Du Xiaohua; Zhao Chengshou; Wang Yuzhong; Zhou Qian; Deng Yi; Qu Minghai; Yang Bing

    2006-01-01

    The flame retardancy and the thermal oxidative degradation behaviors of the blend of poly(ethylene terephthalate) (PET) with a kind of phosphorus-containing thermotropic liquid crystal copolyester (TLCP) with high flame retardancy (limited oxygen index, 70%) have been investigated by oxygen index test (LOI), UL-94 rating and thermogravimetric analysis (TGA) in air. The results show that TLCP can dramatically improve the flame retardancy and the melt dripping behavior of PET. Moreover, the apparent activation energies of thermal oxidative degradation of the blends were evaluated using Kissinger and Flynn-Wall-Ozawa methods. It is found that addition of TLCP improve thermal stability and restrain thermal decomposition of PET in air, especially at the primary degradation stage. Py-GC/MS analysis shows that there are remarkable changes in the pyrolysis products when TLCP are blended into PET. The interaction between TLCP and PET has changed their thermal oxidative degradation mechanism

  1. Unsaturated polyester/expanded polystyrene composite : thermal characteristics and flame retardancy effects

    Science.gov (United States)

    Mohamed, R.; Syed Mustafa, S. A.; Norizan, Mohd N.; Amerudin, L. S.

    2017-07-01

    Panels for energy efficient buildings has to meet certain requirements such as low thermal conductivity and inherent flame retardancy characteristics, before being eligible for buildings and construction applications. Expanded Polystyrene (EPS) as waste material had been incorporated as filler in Unsaturated Polyester Resin (UPR) composites. The composite are fabricated as flat panel window or glazing to replace glass. In this study, different EPS content incorporated was found to affect flammability and thermal characteristics. Core additives such as Flame Retardant (FR) and Antioxidant (AO) were added to the composite for imparting flame retardancy and prevent aging of the composite. The result obtained via the comparison of the various composite systems studied had revealed that organic and metal oxide flame retardant (FR) additives imparts higher flame retardancy levels than others, but each type of additives had interacted with the polymeric matrixes differently. The thermal conductivity, k value, as measured from a handheld thermal probe had showed a minimum of ~0.124 W/m.K for the 1%wt zinc oxide sample, while the highest k value of ~0.280 W/m.K was exhibited by the 2%wt tin oxide sample. The first 1%wt of either metal oxide FR initially decreases both the thermal conductivity, k value; and volumetric specific heat, Cp,v of the samples. At 2%wt, increases in k value were obtained. The flammability was reduced with the use of organic Phosphate Ester FR, which had reduced the flame speed to about 37.1% of the original flame speed. With the equivalent mixture of all three organic FR system, the flammability reduced less than 30%, while the metal oxide FR additive doesn't reduces the flammability.

  2. Thermal and Flame Retardant Properties of Shaped Polypropylene Fibers Containing Modified-Thai Bentonite

    Directory of Open Access Journals (Sweden)

    Prahsarn Chureerat

    2018-03-01

    Full Text Available Tetraphenyl phosphonium-modified organoclay (TPP-Mt was prepared by modifying montmorillonite-rich Thai bentonite via ion exchange. TGA results revealed that TPP-Mt possessed high thermal stability, where degradation occurred at a temperature range of 418-576°C. The obtained TPP-Mt/PP nanocomposites exhibited degradation at higher temperatures than PP (410-420°C vs. 403°C. Fibers of different cross-sectional shapes (circular, circular hollow, and cross containing 1, 2 and 3%wt TPP-Mt were prepared and characterized. Nonwovens of 3%wt TPPMt/PP fibers were fabricated for flame retardant test. From results, nonwovens of TPP-Mt/PP fibers exhibited self-extinguishing characteristic and the areas of burning were less than that of PP nonwoven (14.5-31.6% vs. 95.6%. Nonwovens of cross-shaped fibers showed the best flame retardant property, followed by those of circular hollow and circular fibers. The flame retardant properties observed in nonwovens were explained due to the inter-fiber spaces between cross-shaped fibers and center hole in circular hollow fibers, which could trap initiating radicals inside, thus reducing flame propagation. In addition, large surface area in cross-shaped fibers could help in increasing the flame retardant effectiveness due to more exposure of TPP-Mt particles to the flame. Knowledge obtained in this study offered an approach to produce flame retardant nonwovens via a combination of modified organolcay and fiber shape.

  3. Brominated and organophosphate flame retardants in selected consumer products on the Japanese market in 2008

    International Nuclear Information System (INIS)

    Kajiwara, Natsuko; Noma, Yukio; Takigami, Hidetaka

    2011-01-01

    Highlights: → We examined the flame retardants in electronics, curtains, wallpaper and insulator. → Use of alternative brominated and organophosphate flame retardants was suggested. → All the products investigated also contained PBDEs, TBBPA and polybromophenols. → Incorporation of recycled materials containing hazardous substance was suggested. - Abstract: The concentrations of traditional brominated flame retardants (BFRs) and organophosphate flame retardants (OPFRs) in new consumer products, including electronic equipment, curtains, wallpaper, and building materials, on the Japanese market in 2008 were investigated. Although some components of the electronic equipment contained bromine at concentrations on the order of percent by weight, as indicated by X-ray fluorescence analysis, the bromine content could not be fully accounted for by the BFRs analyzed in this study, which included polybrominated diphenylethers, decabromodiphenyl ethane, tetrabromobisphenol A, polybromophenols, and hexabromocyclododecanes. These results suggest the use of alternative BFRs such as newly developed formulations derived from tribromophenol, tetrabromobisphenol A, or both. Among the 11 OPFRs analyzed, triphenylphosphate was present at the highest concentrations in all the products investigated, which suggests the use of condensed-type OPFRs as alternative flame retardants, because they contain triphenylphosphate as an impurity. Tripropylphosphate was not detected in any samples; and trimethylphosphate, tributyl tris(2-butoxyethyl)phosphate, and tris(1,3-dichloro-2-propyl)phosphate were detected in only some components and at low concentrations. Note that all the consumer products evaluated in this study also contained traditional BFRs in amounts that were inadequate to impart flame retardancy, which implies the incorporation of recycled plastic materials containing BFRs that are of global concern.

  4. Development of halogen-free flame-retardant cable for nuclear power plant. 2

    International Nuclear Information System (INIS)

    Matsumoto, Tetsuo; Kimura, Hitoshi; Ishii, Nobuhisa

    1997-01-01

    Halogen-free flame-retardant cables were developed for PWR nuclear power stations. It was confirmed that the developed cables possess flame retardant property, corrosion resistance, low toxicity and low smoke generation, and withstand the normal operation in the environment in PWR containment vessels for 60 years and loss of coolant accident. In the advancement of LWR technology, it is important to improve the reliability of machinery and equipment, to extend the period of continuous operation, to optimize the operation cycle and to improve the maintenance of plants. By improving halogen-free flame-retardant material and applying it to the cables for nuclear power stations, it can contribute to the above purposes. The required characteristics of these cables are explained, and the targets of development are power cables, control cables, instrumentation cables and insulated wires which do not contain halogen. The basic material is polyolefin, in which flame retardant magnesium hydroxide and the agent for improving radiation resistance are mixed. The corrosive property and toxicity of gases, smoke generation and the prevention of spread of flame when the cables burn and the durability in environment were evaluated. (K.I.)

  5. Preparation of durable flame retardant PAN fabrics based on amidoximation and phosphorylation

    Science.gov (United States)

    Zhang, Yue; Ren, Yuanlin; Liu, Xiaohui; Huo, Tongguo; Qin, Yiwen

    2018-01-01

    This paper aims to develop a method to impart polyacrylonitrile (PAN) fabric durable flame retadancy. PAN fabric was modified with hydroxylamine hydrochloride (HA) to prepare amidoxime PAN fabric (A-PAN) followed by phosphorylation with phosphoric acid (PA) to obtain flame retardant PAN fabric (P-A-PAN). Thermogravimetric (TG) analysis, differential scanning calorimetry (DSC), microscale combustion calorimetry (MCC) and pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS) were used to analyze the thermal degradation process and flame retardant mechanisms. The structure of the fabrics was characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray Photoelectron Spectroscopy (XPS). The surface morphology of fabrics was observed by scanning electron microscope (SEM). Moreover, the flame retardancy of fabrics before and after washing was evaluated by Limiting oxygen index (LOI) and horizontal burning test. The results showed that the P-A-PAN possessed an excellent thermal stability with the highest LOI value of 34.1% and the highest char residue of 55.67% at 800 °C. Most importantly, the P-A-PAN possessed a wonderful flame retardant durability with a little decrease of LOI after 20 washing cycles. When they were ignited, the P-A-PAN fabrics before and after washing were both nonflammable due to the char residue formation of modified fabric.

  6. Neurotoxicity and risk assessment of brominated and alternative flame retardants

    NARCIS (Netherlands)

    Hendriks, Hester S; Westerink, Remco H S

    2015-01-01

    Brominatedflame retardants (BFRs) are widely used chemicals that prevent or slow the onset and spreading of fire. Unfortunately, many of these compounds pose serious threats for human health and the environment, indicating an urgent need for safe(r) and less persistent alternativeflame retardants

  7. Effects of reactive compatibilization on the morphological, thermal, mechanical, and rheological properties of intumescent flame-retardant polypropylene.

    Science.gov (United States)

    Song, Pingan; Shen, Yu; Du, Baoxian; Peng, Mao; Shen, Lie; Fang, Zhengping

    2009-02-01

    Flame-retardant polypropylene (PP) samples were in situ compatibilized with maleic anhydride grafted PP. Compatibilization reaction was verified by an IR spectrum and gel content measurements. Electron microscopy images showed that compatibilization could considerably reduce the size of the flame-retardant domains, control the phase morphology, and improve the interfacial adhesion between PP and intumescent flame retardant (IFR) with different IFR loading levels. The limiting oxygen index (LOI) of flame-retardant PP increased to different extents after compatibilization, indicating an improvement in the flame retardancy. Compatibilization enhanced the thermal stability to some extent and remarkably delayed thermal oxidative degradation of flame-retardant PP. For PP containing 20 wt % flame retardant, the temperature at which the maximum weight loss rate occurred was enhanced by about 99 degrees C after compatibilization. The storage modulus and glass transition temperatures were elevated to different extents. Tensile strengths of samples reduced in the presence of flame retardant alone but in the additional presence of compatibilizer were restored to levels similar to those of pure PP. Elongation-at-break values, however, showed IFR concentration-dependent reductions that were less for compatibilized samples. Furthermore, the complex viscosity of a compatibilized PP melt turned slightly smaller, which is favorable to melt processing.

  8. Wastewater analysis of Census day samples to investigate per capita input of organophosphorus flame retardants and plasticizers into wastewater

    NARCIS (Netherlands)

    O'Brien, J.W.; Thai, P.K.; Brandsma, S.H.; Leonards, P.E.G.; Ort, C.; Mueller, J.F.

    2015-01-01

    The use of organophosphate esters (PFRs) as flame retardants and plasticizers has increased due to the ban of some brominated flame retardants. There is however some concern regarding the toxicity, particularly carcinogenicity and neurotoxicity, of some of the PFRs. In this study we applied

  9. Levels of Brominated Flame Retardants in Dutch fish and Shellfish including an estimation of the dietary intake

    NARCIS (Netherlands)

    Leeuwen, van S.P.J.; Pieters, H.; Mul, de A.; Boer, de J.

    2006-01-01

    Brominated flame retardants (BFRs) are used at relatively high concentrations in various materials and polymers.Their use has expanded considerably during the last three decades. The annual global demand was estimated to 200 000 tons in 1999. The most frequently used brominated flame retardants

  10. THE SYNERGISTIC EFFECT OF HYBRID FLAME RETARDANTS ON PYROLYSIS BEHAVIOUR OF HYBRID COMPOSITE MATERIALS

    Directory of Open Access Journals (Sweden)

    M. T. ALBDIRY

    2012-06-01

    Full Text Available The aim of this investigation is to comprehensively understand the polymeric composite behavior under direct fire sources. The synergistic effects of hybrid flame retardant material on inhabiting the pyrolysis of hybrid reinforced fibers, woven roving (0°- 45° carbon and kevlar (50/50 wt/wt, and an araldite resin composites were studied. The composites were synthesised and coated primarily by zinc borate (2ZnO.3B2O3.3.5H2O and modified by antimony trioxide (Sb2O3 with different amounts (10-30 wt% of flame retardant materials. In the experiments, the composite samples were exposed to a direct flame source generated by oxyacetylene flame (~3000ºC at variable exposure distances of 10-20 mm. The synergic flame retardants role of antimony trioxide and zinc borate on the composite surface noticeably improves the flame resistance of the composite which is attributed to forming a protective mass and heat barrier on the composite surface and increasing the melt viscosity.

  11. Leaching and Transformation of Flame Retardants and Plasticizers under Simulated Landfill Conditions

    OpenAIRE

    Hörsing, Maritha

    2008-01-01

    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, sinc...

  12. Flame-retardant EPDM compounds containing phenanthrene to enhance radiation resistance

    Science.gov (United States)

    Chen, Jian; Huang, Wei; Jiang, Shu-Bin; Li, Xiao-Yan; An, You; Li, Chuang; Gao, Xiao-Ling; Chen, Hong-Bing

    2017-01-01

    Ethylene propylene diene monomer (EPDM) compounds with good flame-retardant and γ-ray radiation resistant properties were prepared by adding complex flame retardants and phenathrene. The resultant EPDM formulations have a long time to ignition (TTI >46 s), a low peak heat release rate (PHRR 341 kW/m2) and a high limited oxygen index (LOI >30). Effects of γ-ray radiation on the resultant flame-retardant EPDM was investigated. The formulated EPDM is a crosslinking dominated polymer under γ-ray radiation. The γ-ray radiation resistant property of EPDM was enhanced by adding phenanthrene. Elongation at break of EPDM formulated with phenanthrene could retain 91% after being irradiated to 0.3 MGy and still retains 40% elongation even after being irradiated to 0.9 MGy, which is much better the control. It is expected that the formulated flame-retardant and radiation resistant EPDM materials could meet the requirements for use in radiation environments.

  13. Legacy and alternative halogenated flame retardants in human milk in Europe : Implications for children's health

    NARCIS (Netherlands)

    Čechová, Eliška; Vojta, Šimon; Kukučka, Petr; Kočan, Anton; Trnovec, Tomáš; Murínová, Ľubica Palkovičová; de Cock, Marijke; van de Bor, Margot; Askevold, Joakim; Eggesbø, Merete; Scheringer, Martin

    2017-01-01

    In this study, 10 polybrominated diphenyl ethers (PBDEs) and 19 alternative halogenated flame retardants (AFRs) were determined in > 450 human milk samples across three European countries, representing northern, western and eastern Europe. This study provides first insights into the occurrence of

  14. Approach for achieving flame retardancy while retaining physical properties in a compatible polymer matrix

    Science.gov (United States)

    Williams, Martha K. (Inventor); Smith, Trent M. (Inventor)

    2011-01-01

    The invention provides polymer blends containing polyhydroxyamide and one or more flammable polymers. The polymer blends are flame retardant and have improved durability and heat stability compared to the flammable polymer portion of the blends. Articles containing the polymer blends are also provided.

  15. Environmental Risk Limits for several phosphate esters, with possible application as flame retardant

    NARCIS (Netherlands)

    Verbruggen EMJ; Rila JP; Traas TP; Posthuma-Doodeman CJAM; Posthumus R; SEC

    2006-01-01

    Maximum Permissible Concentrations (MPC), Negligible Concentrations (NC) and Serious Risk Concentrations (SRCeco) are derived for a number of phosphate esters that are possibly used as flame retardant. These environmental risk limits were derived for the compartments water, soil, and sediment on

  16. Brominated Flame Retardants in the Environment - The Price for our Convenience?

    NARCIS (Netherlands)

    Boer, de J.

    2004-01-01

    This paper reviews information on the occurrence of brominated flame retardants (BFRs) in various environmental compartments. The lack of information on BFRs other than pentabrominated diphenylethers (pentaBDEs) is emphasized, as well as the need for better analytical methods and the need for more

  17. Effects of Organophosphorus Flame Retardants on Spontaneous Activity in Neuronal Networks Grown on Microelectrode Arrays

    Science.gov (United States)

    EFFECTS OF ORGANOPHOSPHORUS FLAME RETARDANTS ON SPONTANEOUS ACTIVITY IN NEURONAL NETWORKS GROWN ON MICROELECTRODE ARRAYS TJ Shafer1, K Wallace1, WR Mundy1, M Behl2,. 1Integrated Systems Toxicology Division, NHEERL, USEPA, RTP, NC, USA, 2National Toxicology Program, NIEHS, RTP, NC...

  18. Toxicity of brominated flame retardants in fish, with emphasis on endocrine effects and reproduction

    NARCIS (Netherlands)

    Kuiper, R.V.

    2007-01-01

    Abstract The abundant use of brominated flame retardants (BFRs) in modern polymers has over the passed decades resulted in contamination of the environment, and BFRs are increasingly found in fish. Laboratory studies have shown that a number of BFRs and BFR-metabolites can interfere with thyroid and

  19. Nanoparticles Decorated on Resin Particles and Their Flame Retardancy Behavior for Polymer Composites

    Directory of Open Access Journals (Sweden)

    Nour F. Attia

    2017-01-01

    Full Text Available New nanocomposites have been developed by doping of amberlite IR120 resin with spherical TiO2 nanoparticles in the presence of maleate diphosphate. Polystyrene composites of resin, maleate diphosphate, and resin-maleate diphosphate were prepared individually. This is in addition to preparation of polymer nanocomposites of polystyrene-resin doped TiO2 nanoparticles-maleate diphosphate. The flame retardancy and thermal stability properties of these developed polymer composites were evaluated. The inclusion of resin and resin doped nanoparticles improved the fire retardant behavior of polystyrene composites and enhanced their thermal stability. Synergistic behavior between flame retardant, resin, and nanoparticles was detected. The rate of burning of the polymer nanocomposites was recorded as 10.7 mm/min achieving 77% reduction compared to pure polystyrene (46.5 mm/min. The peak heat release rate (PHRR of the new polymer composites has reduced achieving 46% reduction compared to blank polymer. The morphology and dispersion of nanoparticles on resin and in polymer nanocomposites were characterized using transmission and scanning electron microscopy, respectively. The flame retardancy and thermal properties were evaluated using UL94 flame chamber, cone tests, and thermogravimetric analysis, respectively.

  20. Assessment of extrusion-sonication process on flame retardant polypropylene by rheological characterization

    Directory of Open Access Journals (Sweden)

    Guadalupe Sanchez-Olivares

    2016-05-01

    Full Text Available In this work, the rheological behavior of flame retardant polypropylene composites produced by two methods: 1 twin-screw extrusion and 2 ultrasound application combined with a static mixer die single-screw extrusion is analyzed in detail; results are related to the morphology of the composites. The flame retardant polymer composites are composed of a polypropylene matrix, an intumescent flame retardant system and functionalized clay. Scanning electron microscopy revealed that the combination of the static mixer die and on-line sonication reduced particle size and improved the dispersion and distribution of the intumescent additives in the polypropylene matrix at the micrometric level. From linear viscoelastic properties, the Han, Cole-Cole and van Gurp-Palmen diagrams characterized the improved particle dispersion of the flame retardant additives. Two well-defined rheological behaviors were observed in these diagrams. These behaviors are independent on clay presence and concentration. In fact, the ultrasound device generates a 3D highly interconnected structure similar to a co-continuous pattern observed in polymer blends as evidenced by rheological measurements. This improvement in the dispersion and distribution of the additives is attributed to the combined effect of the static mixer die and on-line sonication that allowed reducing the additive content while achieving the optimum classification UL94-V0.

  1. Exposure to organophosphate and polybrominated diphenyl ether flame retardants via indoor dust and childhood asthma

    NARCIS (Netherlands)

    Canbaz, D.; van Velzen, M. J. M.; Hallner, E.; Zwinderman, A. H.; Wickman, M.; Leonards, P. E. G.; van Ree, R.; van Rijt, L. S.

    2016-01-01

    Although the ubiquitous detection of polybrominated diphenyl ether (PBDE) and organophosphate flame retardants (PFRs) in indoor dust has raised health concerns, only very few epidemiological studies have assessed their impact on human health. Inhalation of dust is one of the exposure routes of FRs,

  2. In Vitro Human Metabolism of the Flame Retardant Resorcinol Bis(diphenylphosphate) (RDP)

    NARCIS (Netherlands)

    Ballesteros-Gomez, A.M.; Van den Eede, N.; Covaci, A.

    2015-01-01

    Resorcinol bis(diphenylphosphate) (RDP) is widely used as a flame retardant in electrical/electronic products and constitutes a suitable alternative to decabrominated diphenyl ether. Due to its toxicity and its recently reported ubiquity in electronics and house dust, there are increasing concerns

  3. Comparison of Air Sampling Methods for Organophosphate Flame Retardants in Small Environmental Chambers

    Science.gov (United States)

    Organophosphorus flame retardants (OPFRs), such as tris(2-chloroethyl) phosphate (TCEP), tris(1-chlor-2-propyl) phosphate (TCPP), and tris(1,3-dichloro-2-propyl) phosphate (TDCPP), used as additives in industrial and consumer products are being detected in indoor air, house dust,...

  4. Titanate Nanotubes Decorated Graphene Oxide Nanocomposites: Preparation, Flame Retardancy, and Photodegradation

    Science.gov (United States)

    Sang, Bin; Li, Zhi-wei; Li, Xiao-hong; Yu, Lai-gui; Zhang, Zhi-jun

    2017-07-01

    Most polymers exhibit high flammability and poor degradability, which restrict their applications and causes serious environmental problem like "white pollution." Thus, titanate nanotubes (TNTs) were adopted to decorate graphene oxide (GO) by a facile solution method to afford TNTs/GO nanocomposites with potential in improving the flame retardancy and photodegradability of flexible polyvinyl chloride (PVC). Results show that the as-prepared TNTs/GO can effectively improve the thermal stability and flame retardancy than TNTs and GO, especially, the peak heat release rate and total heat release were reduced by 20 and 29% with only 2.5 wt.% loading. And more, the TNTs/GO also improve the photodegradability of PVC compared with the neat PVC. The reasons can be attributed to synergistic flame-retardant and photocatalytic effects between TNTs and GO. The present research could contribute to paving a feasible pathway to constructing polymer-matrix composites with desired flame retardancy and photodegradability, thereby adding to the elimination of white pollution caused by polymers.

  5. Flame-retardant contamination of firefighter personal protective clothing - A potential health risk for firefighters.

    Science.gov (United States)

    Alexander, Barbara M; Baxter, C Stuart

    2016-09-01

    There is a high incidence of cardiovascular disease and certain cancers in firefighters that may be related to their occupational exposure to hazardous substances. Exposure may result from contaminated personal protective gear, as well as from direct exposure at fire scenes. This study characterized flame-retardant contamination on firefighter personal protective clothing to assess exposure of firefighters to these chemicals. Samples from used and unused firefighter protective clothing, including gloves, hoods and a coat wristlet, were extracted with methylene chloride and analyzed by EPA method 8270D Specific Ion Method (SIM) for polybrominated diphenyl ethers (PBDEs). Until recently PBDEs were some of the most common flame-retardant chemicals used in the US. Fifteen of the seventeen PBDEs for which analysis was performed were found on at least one clothing swatch. Every clothing sample, including an unused hood and all three layers of an unused glove, held a detectable concentration of at least one PBDE. These findings, along with previous research, suggest that firefighters are exposed to PBDE flame retardants at levels much higher than the general public. PBDEs are found widely dispersed in the environment and still persist in existing domestic materials such as clothing and furnishings. Firefighter exposure to flame retardants therefore merits further study.

  6. Effect of urea additive on the thermal decomposition kinetics of flame retardant greige cotton nonwoven fabric

    Science.gov (United States)

    Sunghyun Nam; Brian D. Condon; Robert H. White; Qi Zhao; Fei Yao; Michael Santiago Cintrón

    2012-01-01

    Urea is well known to have a synergistic action with phosphorus-based flame retardants (FRs) in enhancing the FR performance of cellulosic materials, but the effect of urea on the thermal decomposition kinetics has not been thoroughly studied. In this study, the activation energy (Ea) for the thermal decomposition of greige...

  7. Occurrence of halogenated flame retardants in commercial seafood species available in European markets

    NARCIS (Netherlands)

    Aznar-alemany, Òscar; Trabalón, Laura; Jacobs, Silke; Barbosa, Vera Liane; Tejedor, Margarita Fernández; Granby, Kit; Kwadijk, Christiaan; Cunha, Sara C.; Ferrari, Federico; Vandermeersch, Griet; Sioen, Isabelle; Verbeke, Wim; Vilavert, Lolita; Domingo, José L.; Eljarrat, Ethel; Barceló, Damià

    2017-01-01

    PBDEs (congeners 28, 47, 99, 100, 153, 154, 183, 209), HBCD (α, β, γ), emerging brominated flame retardants (PBEB, HBB and DBDPE), dechloranes (Dec 602, 603, 604, syn- and anti-DP), TBBPA, 2,4,6-TBP and MeO-PBDEs (8 congeners) were analysed in commercial seafood samples from European countries.

  8. Statewide surveillance of halogenated flame retardants in fish in Illinois, USA.

    Science.gov (United States)

    Widelka, Margaret; Lydy, Michael J; Wu, Yan; Chen, Da

    2016-07-01

    In order to better understand the exposure of aquatic systems to halogenated flame retardant contaminants, the present study investigated a variety of legacy and emerging flame retardants in common carp and largemouth bass collected from 58 stations across Illinois (United States). The data revealed that polybrominated diphenyl ethers (PBDEs) generally dominated the flame retardant residues in Illinois fish. Concentrations of ΣPBDEs (including all detectable PBDE congeners) ranged from 24.7 to 8270 ng/g lipid weight (median: 135 ng/g lw) in common carp and 15-3870 ng/g lw (median: 360 ng/g lw) in largemouth bass. In addition to PBDEs, Dechlorane analogues (i.e. Dec-603, Dec-604, and Chlordane Plus) were also frequently detected. Median concentrations of ΣDechloranes (including all detected Dechlorane analogues) were 34.4 and 23.3 ng/g lw in common carp and largemouth bass, respectively. Other emerging flame retardants, including tetrabromo-o-chlorotoluene (TBCT), hexabromobenzene (HBBZ), 2-ethylhexyltetrabromobenzoate (EH-TBB), and bis(2-ethylhexyl)-3,4,5,6-tetrabromo-phthalate (BEH-TEBP), were also detected in 40-78% of the fish at the monitored stations. Spatial analysis revealed significantly greater PBDE concentrations in fish living in impaired urban streams and lakes compared to those from the impaired agricultural and unimpaired agricultural/urban waters, demonstrating a significant urban influence on PBDE contamination. Future studies and environmental monitoring are recommended to focus on temporal trends of PBDEs and alternative flame retardants, as well as human exposure risks via edible fishes, in the identified Areas of Concern within Illinois. Copyright © 2016. Published by Elsevier Ltd.

  9. Platinum-doped titanate nanotubes/reduced graphene oxide: photocatalytic activity and flame retardancy

    Science.gov (United States)

    Liu, Guangya; Sang, Bin; Zhou, Zhiqi; Li, Zhiwei

    2018-01-01

    The ‘white pollution’ produced by wasted flexible polyvinyl chloride (PVC) with poor degradation ability and the potential fire hazard of PVC with high flammability not only restrict their application but also cause serious environmental problem. Thus platinum-doped titanate nanotubes/reduced graphene oxide (denoted as Pt-TNTs/rGO) nanocomposites were prepared by a facile method in order to improve the visible photodegradation and get rid of the ‘white pollution’ as well as flame retardancy of PVC. The photodegradation activity and flame retardancy effect of the as-prepared Pt-TNTs/rGO nanocomposites were investigated by ultraviolet and visible light irradiation as well as cone calorimetry. Results show that the Pt-TNTs/rGO-PVC nanocomposites exhibit enhanced visible light photodegradation performance (with mass loss being 6.5%) during 15 day exposure to solar irradiation, and good flame retardancy (providing a 44% reduction of total smoke release as compared with that of PVC matrix). Besides, Pt-TNTs/rGO-PVC nanocomposites show suppressed smoke and reduced CO production as compared with the PVC matrix. These results demonstrate that Pt-TNTs/rGO not only get rid of the ‘white pollution’ as the photocatalyst but also improve the fire safety of PVC as the flame retardant. This could be ascribed to the combination effect between Pt-TNTs and rGO. The present research, hopefully, is to pave a potential pathway to constructing polymer-matrix composites with desired photodegradation activity and flame retardancy, thereby shedding light on simultaneously dealing with the ‘white pollution’ and high flammability of polymer matrix like PVC.

  10. Synergistic effect between ammonium polyphosphate and expandable graphite on flame-retarded poly(butylene terephthalate)

    Science.gov (United States)

    Zhang, Weizhou; Ren, Jiawei; Wei, Ting; Guo, Weihong

    2018-02-01

    In this paper, the synergistic effect of ammonium polyphosphate (APP) and expandable graphite (EG) on flame-retarded poly(butylene terephthalate) (PBT) was systermically investigated using limiting oxygen index (LOI), UL-94 testing, microscale combustion calorimetry (MCC), thermal-gravimetric analysis (TGA) and scanning electronic microscopy (SEM). PBT composites containing 20 wt% of APP: EG (1:3) combinations exhibits a high LOI value of 29.8 and reaches V-0 rating in UL-94 testing, indicating that the flame retardant property is greatly enhanced compared to the composites solely with APP or EG. SEM images show that the combination of APP and EG could promote the formation of a compact char layer. The compact char layer protects the PBT resin efficiently by preventing penetration of heat flux inside the matrix and retards the decomposition of PBT, consequently improves the thermal stability of PBT materials as revealed by TGA. All of the results demonstrate that APP and EG are high efficiency synergists for improving the flame retardation of PBT materials.

  11. Detection of Organophosphate Flame Retardants in Furniture Foam and US House Dust

    Science.gov (United States)

    Stapleton, Heather M.; Klosterhaus, Susan; Eagle, Sarah; Fuh, Jennifer; Meeker, John D.; Blum, Arlene; Webster, Thomas F.

    2009-01-01

    Restrictions on the use of polybrominated diphenyl ethers (PBDEs) have resulted in the increased use of alternate flame retardant chemicals to meet flammability standards. However, it has been difficult to determine which chemical formulations are currently being used in high volumes to meet flammability standards since the use of flame retardant formulations in consumer products is not transparent (i.e. not provided to customers). To investigate chemicals being used as replacements for PentaBDE in polyurethane foam, we analyzed foam samples from 26 different pieces of furniture purchased in the United States primarily between 2003 and 2009 using gas chromatography mass spectrometry. Samples included foam from couches, chairs, mattress pads, pillows, and, in one case, foam from a sound proofing system of a laboratory grade dust sieve. Fifteen of the foam samples contained the flame retardant tris(1,3-dichloro-2-propyl) phosphate (TDCPP; 1–5% by weight), four samples contained tris(1-chloro-2-propyl) phosphate (TCPP; 0.5 –2.2 % by weight), one sample contained brominated chemicals found in a new flame retardant mixture called Firemaster 550 (4.2% by weight), and one foam sample collected from a futon likely purchased prior to 2004 contained PentaBDE (0.5% by weight). Due to the high frequency of detection of the chlorinated phosphate compounds in furniture foam, we analyzed extracts from 50 house dust samples collected between 2002 and 2007 in the Boston, MA area for TDCPP, TCPP, and another high volume use organophosphate-based flame retardant used in foam, triphenylphosphate (TPP). Detection frequencies for TDCPP and TPP in the dust samples were >96% and were log normally distributed, similar to observations for PBDEs. TCPP was positively detected in dust in only 24% of the samples, but detection was significantly limited by a co-elution problem. The geometric mean concentrations for TCPP, TDCPP and TPP in house dust were 570, 1890, and 7360 ng/g, respectively

  12. Effect of Particle Size of Additives on the Flammability and Mechanical Properties of Intumescent Flame Retarded Polypropylene Compounds

    Directory of Open Access Journals (Sweden)

    Katalin Bocz

    2015-01-01

    Full Text Available The effect of particle size reduction of the components of a common intumescent flame retardant system, consisting of pentaerythritol (PER and ammonium polyphosphate (APP in a weight ratio of 1 to 2, was investigated on the flammability and mechanical performance of flame retarded polypropylene (PP compounds. Additives of reduced particle size were obtained by ball milling. In the case of PER, the significant reduction of particle size resulted in inferior flame retardant and mechanical performance, while the systems containing milled APP noticeably outperformed the reference intumescent system containing as-received additives. The beneficial effect of the particle size reduction of APP is explained by the better distribution of the particles in the polymer matrix and by the modified degradation mechanism which results in the formation of an effectively protecting carbonaceous foam accompanied with improved mechanical resistance. Nevertheless, 10% higher tensile strength was measured for the flame retarded PP compound when as-received APP was substituted by milled APP.

  13. Prenatal Exposure to Organohalogens, Including Brominated Flame Retardants, Influences Motor, Cognitive, and Behavioral Performance at School Age

    NARCIS (Netherlands)

    Roze, Elise; Meijer, Lisethe; Bakker, Attie; Van Braeckel, Koenraad N. J. A.; Sauer, Pieter J. J.; Bos, Arend F.

    2009-01-01

    BACKGROUND: Organohalogen compounds (OHCs) are known to have neurotoxic effects on the developing brain. OBJECTIVE: We investigated the influence of prenatal exposure to OHCs, including brominated flame retardants, on motor, cognitive, and behavioral outcome in healthy children of school age.

  14. Brominated Flame Retardants: Spatial and Temporal Trends in the Environment and Biota from the Pacific Basin Countries

    Science.gov (United States)

    Brominated flame retardants (BFRs) are used as additive or reactive components in a variety of polymers including high-impact polystyrene and epoxy resins, commercial products such as computers, electronics and electrical equipment, thermal insulation, textiles and furniture foam...

  15. Flame Retardance and Physical Properties of Novel Cured Blends of Unsaturated Polyester and Furan Resins

    Directory of Open Access Journals (Sweden)

    Baljinder Kaur Kandola

    2015-02-01

    Full Text Available Novel blends of two furan resins with an unsaturated polyester have been prepared and cured by parallel free radical (for the unsaturated polyester and acid-catalysed crosslinking (for the furan resin to give co-cured composite materials. Although these materials have inferior physical properties, such as low Tg and low storage modulus compared with those of unsaturated polyester and furan resins alone, they show markedly improved flame retardance compared with that of the normally highly flammable unsaturated polyester. This increased flame retardance arises from a condensed phase mechanism in which the furanic component forms a semi-protective char, reducing rates of thermal degradation and total heat release and heat of combustion. The blends also burn with reduced smoke output compared with that from unsaturated polyester alone.

  16. Intumescent flame retardants for polymers. I. The poly(acrylonitrile)-ammonium polyphosphate-hexabromocyclododecane system

    Energy Technology Data Exchange (ETDEWEB)

    Ballistreri, A.; Montaudo, G.; Puglisi, C.; Scamporrino, E.; Vitalini, D.

    1983-05-01

    The influence of ammonium polyphosphate (APP) and hexabromocyclododecane (HBCD) as flame retardant (FR) on poly(acrylonitrile) (PAN) has been examined. The APP-HBCD system behaves as an intumescent flame retardant (IFR) formulation, APP being the char-forming agent and HBCD the blowing agent. A negligible gas-phase mode of action was ascertained for HBCD with this substrate. A synergism between the two FR agents was observed, corresponding to about 50% increased efficacy with respect to the separate effects of the two components. Thermogravimetry (TG), oxygen index (OI), nitrous oxide index (NOI) experiments and phosphorous residue measurements were performed to substantiate the conclusion that a condensed phase mechanism of action accounts for all the facts observed.

  17. Retrospective analysis of "new" flame retardants in the global atmosphere under the GAPS Network.

    Science.gov (United States)

    Lee, Sum Chi; Sverko, Ed; Harner, Tom; Pozo, Karla; Barresi, Enzo; Schachtschneider, JoAnne; Zaruk, Donna; DeJong, Maryl; Narayan, Julie

    2016-10-01

    A retrospective analysis was conducted on air samples that were collected in 2005 under the Global Atmospheric Passive Sampling (GAPS) Network around the time period when the Stockholm Convention on Persistent Organic Pollutants came into force. Results are presented for several new flame retardants, including hexabromocyclododecane (HBCD), which was recently listed under the Convention (2013). These results represent the first global-scale distributions in air for these compounds. The targeted compounds are shown to have unique global distributions in air, which highlights the challenges in understanding the sources and environmental fate of each chemical, and ultimately in their assessments as persistent organic pollutants. The study also demonstrates the feasibility of using the PUF disk passive air sampler to study these new flame retardants in air, many of which exist entirely in the particle-phase as demonstrated in this study using a KOA-based partitioning model. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  18. A Novel Application of Phosphorene as a Flame Retardant

    Directory of Open Access Journals (Sweden)

    Xinlin Ren

    2018-02-01

    Full Text Available Black phosphorene-waterborne polyurethane (BPWPU composite polymer with 0.2 wt % of black phosphorene was synthesized. Scanning electron microscopy (SEM was used to observe the morphology of phosphorene in polyurethane matrix, which indicated that the phosphorene distributes uniformly in the PU matrix. The flammability measurements were carried out to investigate the flame-resistant performances of phosphorene, which indicated that phosphorene could effectively restrict the degradation of the PU membrane. Compared by the pure WPU, the limiting oxygen index (LOI of BPWPU increased by 2.6%, the heat flow determined by thermal analysis significantly decreased by 34.7% moreover, the peak heat release rate (PHRR decreased by 10.3%.

  19. Detection of organophosphate flame retardants in furniture foam and U.S. house dust.

    Science.gov (United States)

    Stapleton, Heather M; Klosterhaus, Susan; Eagle, Sarah; Fuh, Jennifer; Meeker, John D; Blum, Arlene; Webster, Thomas F

    2009-10-01

    Restrictions on the use of polybrominated diphenyl ethers (PBDEs) have resulted in the increased use of alternate flame retardant chemicals to meet flammability standards. However, it has been difficult to determine which chemical formulations are currently being used in high volumes to meet flammability standards since the use of flame retardant formulations in consumer products is not transparent (i.e., not provided to customers). To investigate chemicals being used as replacements for PentaBDE in polyurethane foam, we analyzed foam samples from 26 different pieces of furniture purchased in the United States primarily between 2003 and 2009. Samples included foam from couches, chairs, mattress pads, pillows, and, in one case, foam from a sound-proofing system of a laboratory-grade dust sieve, and were analyzed using gas chromatography mass spectrometry. Fifteen of the foam samples contained the flame retardanttris(1,3-dichloro-2-propyl) phosphate (TDCPP; 1-5% by weight), four samples contained tris(1-chloro-2-propyl) phosphate (TCPP; 0.5 -22% by weight), one sample contained brominated chemicals found in a new flame retardant mixture called Firemaster 550 (4.2% by weight), and one foam sample collected from a futon likely purchased prior to 2004 contained PentaBDE (0.5% by weight). Due to the high frequency of detection of the chlorinated phosphate compounds in furniture foam,we analyzed extracts from 50 house dust samples collected between 2002 and 2007 in the Boston, MA area for TDCPP, TCPP, and another high volume use organophosphate-based flame retardant used in foam, triphenylphosphate (TPP). Detection frequencies for TDCPP and TPP in the dust samples were > 96% and were log normally distributed, similar to observations for PBDEs. TCPP was positively detected in dust in only 24% of the samples, but detection was significantly limited by a coelution problem. The geometric mean concentrations for TCPP, TDCPP, and TPP in house dust were 570, 1890, and 7360 ng

  20. Occurrence of halogenated and organophosphate flame retardants in sediment and fish samples from three European river basins

    OpenAIRE

    Giulivo, Monica; Capri, Ettore; Kalogianni, Eleni; Milačič, Radmila; Majone, Bruno; Ferrari, Federico; Eljarrat, Ethel; Barceló, Damià

    2017-01-01

    Classic (polybromodiphenyl ethers, PBDEs) and emerging halogenated flame retardants (HFRs) such as decabromodiphenyl ethane (DBDPE) and halogenated norbornenes, as well as organophosphate flame retardants (OPFRs) were analysed in 52 sediments and 27 fish samples from three European river basins, namely the Evrotas (Greece), the Adige (Italy) and the Sava (Slovenia, Croatia, Bosnia and Herzegovina and Serbia). This is the first time that FR levels have been reported in these three European riv...

  1. The Effect of Mg(OH)2 Nanoparticles on the Thermal Stability and Flame Retardancy of Paraloid Nanocomposites

    OpenAIRE

    H. R. Momenian; M. Salavati-Niasari; D. Ghanbari; B. Pedram; F. Mozaffar; S. Gholamrezaei

    2014-01-01

    Paraloid-Mg(OH)2 nanocomposites were synthesized via sonochemical method. Nanostructures were characterized by XRD and SEM. Thermal stability behavior of paraloid filled with magnesium hydroxide was investigated by thermogravimetric analysis (TGA). The influence of Mg(OH)2 nanostructures on the flame retardancy of the paraloid matrix was studied using UL-94 analysis. Our results show that the Mg(OH)2 nanostructure can enhance the flame retardant property of the paraloid matrix. The enhancemen...

  2. Flame Retardant Fibers for Human Space Exploration - Past, Present, and Future

    Science.gov (United States)

    Orndoff, Evelyne

    2017-01-01

    The National Aeronautics and Space Administration (NASA) has led the development of unique flame retardant fibers for the specific requirements of different space programs. Three of these fibers have greatly contributed to the safety of all the space missions since the Apollo program. Beta alumina-silica microfiber developed for the outer layer of the space suit after the Apollo 1 fire is no longer used and has been replaced by other glass fibers. Expanded polytetrafluoroethylene (e-PTFE) fiber used in the current spacesuit is mostly known today through its trade mark Gore-Tex®. Polybenzimidazole (PBI) filament fiber used in many applications from the Apollo to the Space Shuttle program is no longer available. More recently, TOR"TM" copolymer of polyimide fiber developed during the space shuttle program to resist the atomic oxygen present in Low Earth Orbit has been barely used. The high cost and narrow range of aeronautical and aerospace applications have, however, led to a limited production of these fibers. Only fibers that found niche markets survived. Yet, deep space exploration will require more of these inherently flame retardant fibers than what is available today. There is a need for new flame retardant fabrics inside the space vehicles as well as a need for logistics reduction for long term space missions. Materials like modacrylic and polyimide are good candidates for future flame retardant aerospace fabrics. New fabrics must be developed for astronauts' clothing, as well as crew quarters and habitat. Therefore, both staple and filament fibers of various linear densities are needed for a three years mission to Mars.

  3. Combination effect of melamine polyphosphate and graphene on flame retardant properties of poly(vinyl alcohol)

    International Nuclear Information System (INIS)

    Huang Guobo; Liang Huading; Wang Yong; Wang Xu; Gao Jianrong; Fei Zhengdong

    2012-01-01

    Highlights: ► PVA/graphene/MPP composites were prepared by solvent blending. ► PVA/graphene systems improved the flame retardancy of the nanocomposites. ► Flame retardation mechanism was explained by SEM, FT-IR and XPS. - Abstract: A novel flame retardant poly(vinyl alcohol) (PVA)/melamine polyphosphate (MPP)–graphene nanocomposite has been prepared by solvent blending. Results from X-ray diffraction (XRD) and transmission electron microscopy (TEM) suggest that an excellent dispersion of exfoliated graphene and MPP in the PVA matrix was achieved. The thermal and flammability properties of the nanocomposite were investigated using thermogravimetry, cone calorimetry, and flammability tests (UL 94 and LOI). The presence of both MPP and graphene in the polymer matrix led to an enhanced thermal stability and significantly reduced flammability for the nanocomposite. PVA composites filled with 10 wt% MPP and 1 wt% graphene (PVA/G1/MPP10) achieved the LOI value of 29.6 and UL-94 V0 grade. Compared to pure PVA, the peak heat release rate (PHRR) of PVA/G1/MPP10 is reduced by about 60%. Meanwhile, the mechanical properties of PVA/G1/MPP10 composites exhibit almost no deterioration compared with pure PVA. The morphology and composition of residues generated after cone calorimeter tests were investigated by scanning electronic microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The SEM images showed the compact and dense intumescent char jammed with graphene sheets was formed for PVA/G1/MPP10 during combustion. The results of XPS confirmed that carbon content of the char for PVA/G1/MPP10 is increased obviously by the combination effect of the flame retardant MPP and graphene.

  4. Single- and Multiwalled Carbon Nanotubes with Phosphorus Based Flame Retardants for Textiles

    OpenAIRE

    D. Wesolek; W. Gieparda

    2014-01-01

    Due to growing popularity of composites, modification methods to obtain the best properties are searched for. The aim of the study is to reduce the flammability of textile materials using nanocomposite polymer back-coating. Different types of carbon nanotubes (single- and multiwalled) and different phosphorus flame retardants (ammonium polyphosphates and melamine polyphosphate) were introduced into the resin and then the fabrics were covered by the obtained composites. Homogeneous dispersion ...

  5. Flame retardant materials based on BDM/DBA resin and organic-inorganic additives

    OpenAIRE

    Wang, Zheng

    2017-01-01

    2,2’-diallyl bisphenol A (DBA) modified bismaleimide resins (BDM) are widely used as polymer matrix of high-performance composites in the field of aerospace, transportation, machinery, and electronics. This kind of resin has excellent properties, including good thermal stability, good processing performance, high mechanical strength, excellent dielectric properties, etc. However, as for most organic resins, the flame retardancy of the BMI resins is not so good. In order to expand the use of t...

  6. Assessing oestrogenic effects of brominated flame retardants Hexabromocyclododecane and Tetrabromobisphenol A on MCF-7 cells

    Czech Academy of Sciences Publication Activity Database

    Dorosh, Andriy; Děd, Lukáš; Elzeinová, Fatima; Pěknicová, Jana

    2010-01-01

    Roč. 56, - (2010), s. 35-39 ISSN 0015-5500 R&D Projects: GA MŠk(CZ) 1M06011; GA MŠk(CZ) 2B06151 Institutional research plan: CEZ:AV0Z50520701 Keywords : endocrine disruptors * BRF - brominated flame retardant * MCF-7 cells * TFF1 - trefoil factor Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 0.729, year: 2010

  7. Associations between brominated flame retardants in house dust and hormone levels in men

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Paula I. [Department of Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Stapleton, Heather M. [Nicholas School of the Environment, Box 90328, Duke University, Durham, NC 27708 (United States); Mukherjee, Bhramar [Department of Biostatistics, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Hauser, Russ [Department of Environmental Health, Harvard School of Public Health, 677 Huntington Ave., Boston, MA 02115 (United States); Meeker, John D., E-mail: meekerj@umich.edu [Department of Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109 (United States)

    2013-02-15

    Brominated flame retardants (BFRs) are used in the manufacture of a variety of materials and consumer products in order to meet fire safety standards. BFRs may persist in the environment and have been detected in wildlife, humans and indoor dust and air. Some BFRs have demonstrated endocrine and reproductive effects in animals, but human studies are limited. In this exploratory study, we measured serum hormone levels and flame retardant concentrations [31 polybrominated diphenyl ether (PBDE) congeners and 6 alternate flame retardants] in house dust from men recruited through a US infertility clinic. PBDE congeners in dust were grouped by commercial mixtures (i.e. penta-, octa- and deca-BDE). In multivariable linear regression models adjusted by age and body mass index (BMI), significant positive associations were found between house dust concentrations of pentaBDEs and serum levels of free T4, total T3, estradiol, and sex hormone binding globulin (SHBG), along with an inverse association with follicle stimulating hormone (FSH). There were also positive associations of octaBDE concentrations with serum free T4, thyroid stimulating hormone (TSH), luteinizing hormone (LH) and testosterone and an inverse association of decaBDE concentrations with testosterone. Hexabromocyclododecane (HBCD) was associated with decreased SHBG and increased free androgen index. Dust concentrations of bis-tribromophenoxyethane (BTBPE) and tetrabromo-diethylhexylphthalate (TBPH) were positively associated with total T3. These findings are consistent with our previous report of associations between PBDEs (BDE 47, 99 and 100) in house dust and hormone levels in men, and further suggest that exposure to contaminants in indoor dust may be leading to endocrine disruption in men. - Highlights: ► Brominated flame retardants (BFRs) including PBDEs and alternates were measured. ► Exposure to BFRs is characterized from concentrations in participant vacuum bag dust. ► Exposure to PBDEs and

  8. House dust concentrations of organophosphate flame retardants in relation to hormone levels and semen quality parameters.

    Science.gov (United States)

    Meeker, John D; Stapleton, Heather M

    2010-03-01

    Organophosphate (OP) compounds, such as tris(1,3-dichloro-2-propyl) phosphate (TDCPP) and triphenyl phosphate (TPP), are commonly used as additive flame retardants and plasticizers in a wide range of materials. Although widespread human exposure to OP flame retardants is likely, there is a lack of human and animal data on potential health effects. We explored relationships of TDCPP and TPP concentrations in house dust with hormone levels and semen quality parameters. We analyzed house dust from 50 men recruited through a U.S. infertility clinic for TDCPP and TPP. Relationships with reproductive and thyroid hormone levels, as well as semen quality parameters, were assessed using crude and multivariable linear regression. TDCPP and TPP were detected in 96% and 98% of samples, respectively, with widely varying concentrations up to 1.8 mg/g. In models adjusted for age and body mass index, an interquartile range (IQR) increase in TDCPP was associated with a 3% [95% confidence interval (CI), 5% to 1%) decline in free thyroxine and a 17% (95% CI, 432%) increase in prolactin. There was a suggestive inverse association between TDCPP and free androgen index that became less evident in adjusted models. In the adjusted models, an IQR increase in TPP was associated with a 10% (95% CI, 219%) increase in prolactin and a 19% (95% CI, 30% to 5%) decrease in sperm concentration. OP flame retardants may be associated with altered hormone levels and decreased semen quality in men. More research on sources and levels of human exposure to OP flame retardants and associated health outcomes are needed.

  9. Urinary Metabolites of Organophosphate Flame Retardants and Their Variability in Pregnant Women

    OpenAIRE

    Hoffman, Kate; Daniels, Julie L.; Stapleton, Heather M.

    2013-01-01

    Organophosphate flame retardants (OPFRs) are commonly added to consumer products to reduce their flammability. Based on levels of OPFRs in indoor environments, human exposure is likely chronic and ubiquitous. Animal studies suggest that exposure to some OPFRs may result in adverse health impacts, particularly for tris (1,3-dichloropropyl) phosphate (TDCPP); however, human data on the impacts of exposure to OPFRs are lacking. To design human studies, more information is needed on the stability...

  10. Human Indoor Exposure to Airborne Halogenated Flame Retardants: Influence of Airborne Particle Size

    OpenAIRE

    La Guardia, Mark J.; Schreder, Erika D.; Uding, Nancy; Hale, Robert C.

    2017-01-01

    Inhalation of halogenated flame-retardants (HFRs) released from consumer products is an important route of exposure. However, not all airborne HFRs are respirable, and thus interact with vascular membranes within the gas exchange (alveolar) region of the lung. HFRs associated with large (>4 ?m), inhalable airborne particulates are trapped on the mucosal lining of the respiratory tract and then are expelled or swallowed. The latter may contribute to internal exposure via desorption from partic...

  11. Characterizing the In Vitro Hepatic Biotransformation of the Flame Retardant BDE 99 by Common Carp

    OpenAIRE

    Noyes, Pamela D.; Kelly, Shannon M.; Mitchelmore, Carys L.; Stapleton, Heather M.

    2009-01-01

    Polybrominated diphenyl ethers (PBDEs) are a class of flame retardant chemicals that are known to biomagnify in aquatic foodwebs. However, significant biotransformation of some congeners via reductive dehalogenation has been observed during in vivo and in vitro laboratory exposures, particularly in fish models. Little information is available on the enzyme systems responsible for catalyzing this metabolic pathway in fish. This study was undertaken to characterize the biotransformation of one ...

  12. Melamine-containing polyphosphazene wrapped ammonium polyphosphate: A novel multifunctional organic-inorganic hybrid flame retardant.

    Science.gov (United States)

    Qiu, Shuilai; Ma, Chao; Wang, Xin; Zhou, Xia; Feng, Xiaming; Yuen, Richard K K; Hu, Yuan

    2018-02-15

    To achieve superior fire safety epoxy resins (EP), a novel multifunctional organic-inorganic hybrid, melamine-containing polyphosphazene wrapped ammonium polyphosphate (PZMA@APP) with rich amino groups was prepared and used as an efficient flame retardant. Thanks to the cross-linked polyphosphazene part, PZMA@APP exhibited high flame retardant efficiency and smoke suppression to the EP composites. Thermogravimetric analysis indicated that PZMA@APP significantly enhanced the thermal stability of EP composites. The obtained sample passed UL-94 V-0 rating with 10.0wt% addition of PZMA@APP. Notably, inclusion of incorporating PZMA@APP leads to significantly decrease on fire hazards of EP, for instance, bring about a 75.6% maximum decrease in peak heat release rate and 65.9% maximum reduction in total heat release, accompanied with lower smoke production rate and higher graphitized char layer. With regards to mechanical property, the glass transition temperature of EP/PZMA@APP10.0 was as high as 184.5°C. In particular, the addition of PZMA@APP did not worsen the mechanical properties, compared to pure APP. It was confirmed that the participation of melamine-containing polyphosphazene could significantly enhance the quality of char layer and thereby resulting the higher flame retardant efficiency of PZMA@APP. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. The analysis of halogenated flame retardants by GC-HRMS in environmental samples.

    Science.gov (United States)

    Kolic, Terry M; Shen, Li; Macpherson, Karen; Fayez, Laila; Gobran, Teresa; Helm, Paul A; Marvin, Chris H; Arsenault, Gilles; Reiner, Eric J

    2009-01-01

    The analytical conditions required to determine polybrominated diphenylethers (PBDEs) and a variety of other halogenated flame retardants (HFRs) by gas chromatography-high resolution mass spectrometry (HRMS) in environmental samples are reported. HRMS can be used to analyze brominated diphenylethers (BDEs), 2,2',4,4',5,5'-hexabromobiphenyl (BB-153) as well as for a number of other emerging HFRs like allyl 2,4,6-tribromophenyl ether (ATE), 2-bromoallyl 2,4,6-tribromophenyl ether (BATE), 2,3-dibromopropyl 2,4,6-tribromophenyl ether (DPTE), octabromotrimethylphenylindane (OBIND), pentabromoethylbenzene (PBEB), hexabromobenzene (HBB), 1,2-bis (2,4,6-tribromophenoxy) ethane (BTBPE), decabromodiphenylethane (DBDPE), Dechlorane Plus (DP), hexachlorocyclopentadienyl-dibromocyclooctane (HCDBCO), tetrabromoethylcyclohexane (TBECH), 1,2,5,6-tetrabromocylcooctane (TBCO), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EHTeBB), and bis(2-ethly-1-hexyl)tetrabromophthalate (BEHTBP). The detection in environmental matrices and use of these non-BDE flame retardants is reviewed. A method for the analysis of PBDEs by isotope dilution HRMS and 16 other halogenated compounds primarily used as flame retardants is reported. A survey of selected environmental samples, which included Lake Ontario surface and tributary sediments, municipal wastewater effluent, sludge, and mussel tissues, detected PBDEs, DP, DBDPE, BTBPE, PBEB, BB-153, and HBB.

  14. A novel branched phosphorus-containing flame retardant: synthesis and its application

    Science.gov (United States)

    Zhang, Yi; Liu, Jiping; Li, Shulei

    2018-03-01

    A novel branched polyphosphonate flame retardant (BPDD) has been synthesized through melt polycondensation and end-capping reaction. The chemical structure of BPDD was characterized by fourier transform infrared (FTIR) spectra and nuclear magnetic resonance (NMR) spectra. The test results of the vertical burning test (UL-94), limiting oxygen index (LOI) and cone calorimeter (CONE) measurements reveal that BPDD can effectively enhanced flame-retardant properties of EP. The LOI values of EP/BPDD composites increased from 23.9 % of pure EP to 33.6% and UL-94 V-0 was obtained with the 20 wt% BPDD loading. Besides, the peak heat release rate (PHRR) and total heat release (THR) of EP/BPDD composites were reduced significantly compared with the pure EP. When 20 wt% BPPD was incorporated, the PHRR and THR were decreased 66.2 % and 37.3%, respectively. The comprehensive test results shows that the improvement of flame retardancy of the EP/BPDD composites was attributed to the synergistic action of the condensed phase and gas phases.

  15. The properties of neutron shielding and flame retardant of EVA polymer after modified by EB accelerator

    Science.gov (United States)

    Wang, Guo-hui; He, Man-li; Jiang, Dan-feng; He, Fan; Chang, Shu-quan; Dai, Yao-dong

    2017-11-01

    According to the requirements for neutron shielding and flame retardant properties of some nuclear devices, a new kind of polymer composite materials based on ethylene and vinyl acetate (EVA) polymer have been studied. EVA is the copolymer of ethylene and vinyl acetate, It can be used as materials for applications due to its flexibility, good processability, and low cost. Insulating EVA can be used for cable sheath, automotive sound damping and many other appication. Boron nitride (BN), zinc borate (ZB), magnesium hydroxide (MH) and EVA consisted the compounds with the properties of neutron shielding and flame retardant. With increasing of the contents of BN and ZB, the neutron shielding performance of materials increased up to 33.08%. With the increasing contents of MH and ZB as flame retardant, oxygen index of material have been improved. The elongation at break and tensile strength of material decreased with the increasing of filler powders. Sheet E was chosen and modified by electron beam accelerator in different doses. After modification by electron beam irradiation the sheets showed varying degrees of transformation in the OI, neutron shielding rate and mechanical properties.

  16. Adsorption and Flame Retardant Properties of Bio-Based Phytic Acid on Wool Fabric

    Directory of Open Access Journals (Sweden)

    Xian-Wei Cheng

    2016-04-01

    Full Text Available Bio-based phytic acid (PA as a nontoxic naturally occurring compound is a promising prospect for flame-retardant (FR modifications to polymers. In this work, PA was applied to wool fabric using an exhaustion technique, and the adsorption and FR properties of PA on wool fabric were studied. The flame retardancy of the treated wool fabrics depended greatly on the adsorption quantity of PA, which was related to the pH of treatment solution, immersing temperature and initial PA concentration. The Langmuir adsorption of PA took place due to electrostatic interactions between PA and wool fiber. The limiting oxygen index, vertical burning and pyrolysis combustion flow calorimetry tests revealed that the treated wool fabrics exhibited good flame retardancy. The measurements of the phosphorus content of the burned fabric residues and thermogravimetric analyses suggested that a significant condensed-phase FR action was applicable to the PA treated fabrics. PA treatment was found to have little adverse effect on the whiteness and mechanical performance of wool. Additionally, the washing resistance of the FR fabrics should be further improved.

  17. Recent Advances for Flame Retardancy of Textiles Based on Phosphorus Chemistry

    Directory of Open Access Journals (Sweden)

    Khalifah A. Salmeia

    2016-08-01

    Full Text Available This paper aims at updating the progress on the phosphorus-based flame retardants specifically designed and developed for fibers and fabrics (particularly referring to cotton, polyester and their blends over the last five years. Indeed, as clearly depicted by Horrocks in a recent review, the world of flame retardants for textiles is still experiencing some changes that are focused on topics like the improvement of its effectiveness and the replacement of toxic chemical products with counterparts that have low environmental impact and, hence, are more sustainable. In this context, phosphorus-based compounds play a key role and may lead, possibly in combination with silicon- or nitrogen-containing structures, to the design of new, efficient flame retardants for fibers and fabrics. Therefore, this review thoroughly describes the advances and the potentialities offered by the phosphorus-based products recently developed at a lab-scale, highlighting the current limitations, open challenges and some perspectives toward their possible exploitation at a larger scale.

  18. Effects on heat stress of a flame-retardant ensemble for aluminum smelters.

    Science.gov (United States)

    Cortés-Vizcaíno, C; Bernard, T E

    2000-01-01

    A common belief is that a flame-retardant clothing ensemble will increase the level of heat stress over ordinary cotton work clothes. This is supported by bench tests on fabrics that indicate higher insulation and vapor resistance values for flame-retardant clothing. This research compared a flame-retardant clothing ensemble for an aluminum smelter (Zirpo wool shirt and FR8 denim pants) with typical cotton work clothing. Four young men walked on a treadmill at two work levels inside a climatic chamber under controlled conditions of heat stress. During each test, heart rate, core temperature, and skin temperatures were continuously monitored and recorded every 5 min. After a physiological steady state was achieved, temperature and humidity were slowly increased to maintain a relative humidity of 50%. The critical condition was the time when thermal regulatory control was lost (called the inflection point, marked by a steady increase in core temperature). The climatic conditions at the inflection point were used to assign a critical wet-bulb globe temperature (WBGT). A three-way analysis of variance examined the effects on critical WBGT of clothing, work level, subjects, and the interaction between clothing and work level. There were no significant findings. Therefore, there should be no difference in the level of heat stress between the two clothing ensembles under the same environmental and work conditions.

  19. Flame Retardancy of PA6 Using a Guanidine Sulfamate/Melamine Polyphosphate Mixture

    Directory of Open Access Journals (Sweden)

    Mathieu Coquelle

    2015-02-01

    Full Text Available Polyamide 6 (PA6 is a widely-used polymer that could find applications in various sectors, including home textiles, transportation or construction. However, due to its organic nature, PA6 is flammable, and flame-retardant formulations have to be developed to comply with fire safety standards. Recently, it was proposed to use ammonium sulfamate as an effective flame retardant for PA6, even at low loading content. However, processing issues could occur with this additive considering large-scale production. This paper thus studies the use of another sulfamate salt—guanidine sulfamate (GAS—and evidences its high efficiency when combined with melamine polyphosphate (MPP as a flame retardant for PA6. A decrease of the peak of the heat release rate by 30% compared to pure PA6 was obtained using only 5 wt% of a GAS/MPP mixture in a microscale calorimeter. Moreover, PA6 containing the mixture GAS/MPP exhibits a Limiting Oxygen Index (LOI of 37 vol% and is rated V0 for the UL 94 test (Vertical Burning Test; ASTM D 3801. The mechanisms of degradation were investigated analyzing the gas phase and solid phase when the material degrades. It was proposed that MPP and GAS modify the degradation pathway of PA6, leading to the formation of nitrile end-group-containing molecules. Moreover, the formation of a polyaromatic structure by the reaction of MPP and PA6 was also shown.

  20. Enhancement of flame retardancy and water repellency properties of cotton fabrics using silanol based nano composites.

    Science.gov (United States)

    Mohamed, Amina L; El-Sheikh, Manal A; Waly, Ahmed I

    2014-02-15

    Environmental concerns related to fluorinated and organophosphorus compounds led to a consideration of the methods for imparting flame retardancy and water/oil repellency to textiles. A simple and facile method for fabricating the cotton fabric with superhydrophobicity and flame retardancy is described in the present work. Complex coating with amino-functionalized silica nano-particles on epoxy-functionalized cotton accompanied with ZnO nano-particles coating are carried out. In This context, new preparation techniques were used to prepare both aminated silica and ZnO nano-particles. The particle size was investigated using Transition Electron Microscope (TEM) and the chemical structure was investigated using FT-IR analysis and other analytical techniques. Cotton was functionalized with epoxy and carboxyl via grafting cotton with nano-emulsion consisted of mixture of glycidyl methacrylate (GMA) and acrylic acid (AA), and then treated for functional finishing through conventional pad-dry-cure method. The treated fabrics showed good water repellency and excellent flame retardant properties as determined by the standard test methods. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Lignin-Modified Carbon Nanotube/Graphene Hybrid Coating as Efficient Flame Retardant

    Directory of Open Access Journals (Sweden)

    Kunlin Song

    2017-11-01

    Full Text Available To reduce fire hazards and expand high-value applications of lignocellulosic materials, thin films comprising graphene nanoplatelets (GnPs and multi-wall carbon nanotubes (CNTs pre-adsorbed with alkali lignin were deposited by a Meyer rod process. Lightweight and highly flexible papers with increased gas impermeability were obtained by coating a protective layer of carbon nanomaterials in a randomly oriented and overlapped network structure. Assessment of the thermal and flammability properties of papers containing as low as 4 wt % carbon nanomaterials exhibited self-extinguishing behavior and yielded up to 83.5% and 87.7% reduction in weight loss and burning area, respectively, compared to the blank papers. The maximum burning temperature as measured by infrared pyrometry also decreased from 834 °C to 705 °C with the presence of flame retardants. Furthermore, papers coated with composites of GnPs and CNTs pre-adsorbed with lignin showed enhanced thermal stability and superior fire resistance than samples treated with either component alone. These outstanding flame-retardant properties can be attributed to the synergistic effects between GnPs, CNTs and lignin, enhancing physical barrier characteristics, formation of char and thermal management of the material. These results provide great opportunities for the development of efficient, cost-effective and environmentally sustainable flame retardants.

  2. Assessment of flame retardants in river water using a ceramic dosimeter passive sampler

    International Nuclear Information System (INIS)

    Cristale, Joyce; Katsoyiannis, Athanasios; Chen, Chang'er; Jones, Kevin C.; Lacorte, Silvia

    2013-01-01

    Novel brominated (BFRs) and organophosphorus (OPFRs) flame retardants were monitored in river water using the ceramic dosimeter passive sampling device with HLB (hydrophilic–lipophilic balance) as sorbent. Laboratory calibrations were performed to determine sampling rates for each compound using the Archie's law exponent. The passive sampling device was used to determine the presence of 6 BFRs in the River Aire (United Kingdom), selected according to their ubiquitous presence in the River Aire. Passive sampling integrated river water concentrations ranged from 0.010 to 5.6 μg L −1 for all OPFRs, while BFRs were not detected with this specific passive sampler configuration. Decreased sampling rates were evidenced after 3 weeks of deployment, probably due to fouling. Good agreement between integrated and snapshot water concentrations was obtained, indicating the efficiency of the passive sampler for the monitoring of OPFRs in river water. - Graphical abstract: Display Omitted Highlights: ► Ceramic dosimeter used for the first time with HLB as sorbent. ► Good agreement observed between active and passive sampling water concentrations. ► Organophosphorous flame retardants occur in high concentrations in UK Rivers. - Ceramic dosimeter using HLB as sorbent can be an efficient river-water passive sampler for organophosphorous and brominated flame retardants.

  3. Role of oxygen and DOM in sunlight induced photodegradation of organophosphorous flame retardants in river water.

    Science.gov (United States)

    Cristale, Joyce; Dantas, Renato F; De Luca, Antonella; Sans, Carmen; Esplugas, Santiago; Lacorte, Silvia

    2017-02-05

    The wide use of organophosphorous flame retardants (OPFR) and plasticizers causes a continuous release of large quantities into natural waters. One of the main contributors to micropollutants depletion in surface water is sunlight induced phototransformations. This study aims to elucidate whether alkyl, chloroalkyl and aryl organophosphorus flame retardants undergo phototransformations in river water. To perform the experiments, nine OPFR were subjected to natural sunlight, Xe lamp (simulated sunlight) and UV-C irradiations in ultra-pure Milli-Q water, Milli-Q water with humic acid and river water. Experiments demonstrated that OPFR achieve an important degree of photodegradation noticeable at long irradiation time, although direct photolysis did not account as the main photodegration mechanism. Results indicated that sunlight absorbing OPFR exhibited photosensitizing activity. The presence of azide in ultra- pure water inhibited some OPFR photodegration by singlet oxygen ( 1 O 2 ) scavenging, and the absence of dissolved oxygen significantly depleted most of OPFR removal. In the conditions studied, humic acid inhibited OPFR phototransformations, while river water enhanced their removal. Results from this study point out the need to further investigate the role of some OPFR as photosensitizers, which are important for fate and ecological risk assessment of flame retardants and other micropollutants in water. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Preparation and properties of novel epoxy/graphene oxide nanosheets (GON) composites functionalized with flame retardant containing phosphorus and silicon

    International Nuclear Information System (INIS)

    Li, Kuo-Yi; Kuan, Chen-Feng; Kuan, Hsu-Chiang; Chen, Chia-Hsun; Shen, Ming-Yuan; Yang, Jia-Ming; Chiang, Chin-Lung

    2014-01-01

    2-(Diphenylphosphino)ethyltriethoxy silane (DPPES) was grafted onto the surface of graphene oxide nanosheets (GON) via a condensation reaction. X-ray photoelectron spectroscopy, X-ray diffractometry, Fourier transform infrared spectroscopy and Raman spectroscopy verify that DPPES did not only covalently bond to GON as a functionalization moiety, but partly restored its conjugated structure as a reducing agent. DPPES on graphene sheets oxide was observed by transmission electron microscopy, and contributed to the favorable dispersion of DPPES-GON in nonpolar toluene. Additionally, the flame retardancy and thermal stability of epoxy/DPPES-GON nanocomposites that contain various weight fractions of DPPES-GON were studied using the limiting oxygen index test, UL-94 test and by thermogravimetric analysis in nitrogen. The composites containing 10 wt% DPPES-GON can pass V-0 rating in UL-94 test. Adding 10 wt% DPPES-GON in epoxy greatly increased the char yield and LOI by 42% and 80%, respectively. Epoxy/DPPES-GON nanocomposites with phosphorus, silicon and graphene layer structures were found to exhibit much greater flame retardancy than neat epoxy. The synergistic effects among silicon, phosphorus and GON can improve the flame retardancy of epoxy resin. - Highlights: • Flame retardant was grafted on the surface of graphene oxide nanosheets (GON) by the condensation reaction. • The synergistic effect between silicon, phosphorus and GON improved the flame retardance of epoxy resin. • Epoxy composites have excellent flame retardance at low additive concentrations

  5. Preparation of Flame Retardant Polyacrylonitrile Fabric Based on Sol-Gel and Layer-by-Layer Assembly.

    Science.gov (United States)

    Ren, Yuanlin; Huo, Tongguo; Qin, Yiwen; Liu, Xiaohui

    2018-03-23

    This paper aims to develop a novel method, i.e., sol-gel combined with layer-by-layer assembly technology, to impart flame retardancy on polyacrylonitrile (PAN) fabrics. Silica-sol was synthesized via the sol-gel process and acted as cationic solution, and phytic acid (PA) was used as the anionic medium. Flame-retardant-treated PAN fabric (FR-PAN) could achieve excellent flame retardancy with 10 bilayer (10BL) coating through layer-by-layer assembly. The structure of the fabrics was characterized by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The thermal stability and flame retardancy were evaluated by thermogravimetric (TG) analysis, cone calorimetry (CC) and limiting oxygen index (LOI). The LOI value of the coated fabric was up to 33.2 vol % and the char residue at 800 °C also increased to 57 wt %. Cone calorimetry tests revealed that, compared to the control fabric, the peak of heat release rate (PHRR) and total heat release (THR) of FR-PAN decreased by 66% and 73%, respectively. These results indicated that sol-gel combined with layer-by-layer assembly technique could impart PAN fabric with satisfactory flame-retardant properties, showing an efficient flame retardant strategy for PAN fabric.

  6. Process Optimization of Eco-Friendly Flame Retardant Finish for Cotton Fabric: a Response Surface Methodology Approach

    Science.gov (United States)

    Yasin, Sohail; Curti, Massimo; Behary, Nemeshwaree; Perwuelz, Anne; Giraud, Stephane; Rovero, Giorgio; Guan, Jinping; Chen, Guoqiang

    The n-methylol dimethyl phosphono propionamide (MDPA) flame retardant compounds are predominantly used for cotton fabric treatments with trimethylol melamine (TMM) to obtain better crosslinking and enhanced flame retardant properties. Nevertheless, such treatments are associated with a toxic issue of cancer-causing formaldehyde release. An eco-friendly finishing was used to get formaldehyde-free fixation of flame retardant to the cotton fabric. Citric acid as a crosslinking agent along with the sodium hypophosphite as a catalyst in the treatment was utilized. The process parameters of the treatment were enhanced for optimized flame retardant properties, in addition, low mechanical loss to the fabric by response surface methodology using Box-Behnken statistical design experiment methodology was achieved. The effects of concentrations on the fabric’s properties (flame retardancy and mechanical properties) were evaluated. The regression equations for the prediction of concentrations and mechanical properties of the fabric were also obtained for the eco-friendly treatment. The R-squared values of all the responses were above 0.95 for the reagents used, indicating the degree of relationship between the predicted values by the Box-Behnken design and the actual experimental results. It was also found that the concentration parameters (crosslinking reagents and catalysts) in the treatment formulation have a prime role in the overall performance of flame retardant cotton fabrics.

  7. Flame retardant behavior of polyelectrolyte-clay thin film assemblies on cotton fabric.

    Science.gov (United States)

    Li, Yu-Chin; Schulz, Jessica; Mannen, Sarah; Delhom, Chris; Condon, Brian; Chang, Sechin; Zammarano, Mauro; Grunlan, Jaime C

    2010-06-22

    Cotton fabric was treated with flame-retardant coatings composed of branched polyethylenimine (BPEI) and sodium montmorillonite (MMT) clay, prepared via layer-by-layer (LbL) assembly. Four coating recipes were created by exposing fabric to aqueous solutions of BPEI (pH 7 or 10) and MMT (0.2 or 1 wt %). BPEI pH 10 produces the thickest films, while 1 wt % MMT gives the highest clay loading. Each coating recipe was evaluated at 5 and 20 bilayers. Thermogravimetric analysis showed that coated fabrics left as much as 13% char after heating to 500 degrees C, nearly 2 orders of magnitude more than uncoated fabric, with less than 4 wt % coming from the coating itself. These coatings also reduced afterglow time in vertical flame tests. Postburn residues of coated fabrics were examined with SEM and revealed that the weave structure and fiber shape in all coated fabrics were preserved. The BPEI pH 7/1 wt % MMT recipe was most effective. Microcombustion calorimeter testing showed that all coated fabrics reduced the total heat release and heat release capacity of the fabric. Fiber count and strength of uncoated and coated fabric are similar. These results demonstrate that LbL assembly is a relatively simple method for imparting flame-retardant behavior to cotton fabric. This work lays the foundation for using these types of thin film assemblies to make a variety of complex substrates (foam, fabrics, etc.) flame resistant.

  8. Brominated and organophosphate flame retardants target different neurodevelopmental stages, characterized with embryonic neural stem cells and neuronotypic PC12 cells.

    Science.gov (United States)

    Slotkin, Theodore A; Skavicus, Samantha; Stapleton, Heather M; Seidler, Frederic J

    2017-09-01

    In addition to their activity as endocrine disruptors, brominated and organophosphate flame retardants are suspected to be developmental neurotoxicants, although identifying their specific mechanisms for that activity has been elusive. In the current study, we evaluated the effects of several flame retardants on neurodifferentiation using two in vitro models that assess distinct "decision nodes" in neural cell development: embryonic rat neural stem cells (NSCs), which evaluate the origination of neurons and glia from precursors, and rat neuronotypic PC12 cells, which characterize a later stage where cells committed to a neuronal phenotype undergo neurite outgrowth and neurotransmitter specification. In NSCs, both brominated and organophosphate flame retardants diverted the phenotype in favor of glia and away from formation of neurons, leading to an increased glia/neuron ratio, a common hallmark of the in vivo effects of neurotoxicants. For this early decision node, the brominated flame retardants were far more potent than the organophosphates. In PC12 cells, the brominated flame retardants were far less effective, whereas tris (1,3-dichloro-2-propyl) phosphate, an organophosphate, was more effective. Thus, the two classes of flame retardants differentially impact the two distinct vulnerable periods of neurodifferentiation. Furthermore, the effects on neurodifferentiation were separable from outright cytotoxicity, an important requirement in establishing a specific effect of these agents on neural cell development. These results reinforce the likelihood that flame retardants act as developmental neurotoxicants via direct effects on neural cell differentiation, over and above other activities that can impact nervous system development, such as endocrine disruption. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. The presence and partitioning behavior of flame retardants in waste, leachate, and air particles from Norwegian waste-handling facilities.

    Science.gov (United States)

    Morin, Nicolas A O; Andersson, Patrik L; Hale, Sarah E; Arp, Hans Peter H

    2017-12-01

    Flame retardants in commercial products eventually make their way into the waste stream. Herein the presence of flame retardants in Norwegian landfills, incineration facilities and recycling sorting/defragmenting facilities is investigated. These facilities handled waste electrical and electronic equipment (WEEE), vehicles, digestate, glass, combustibles, bottom ash and fly ash. The flame retardants considered included polybrominated diphenyl ethers (∑BDE-10) as well as dechlorane plus, polybrominated biphenyls, hexabromobenzene, pentabromotoluene and pentabromoethylbenzene (collectively referred to as ∑FR-7). Plastic, WEEE and vehicles contained the largest amount of flame retardants (∑BDE-10: 45,000-210,000μg/kg; ∑FR-7: 300-13,000μg/kg). It was hypothesized leachate and air concentrations from facilities that sort/defragment WEEE and vehicles would be the highest. This was supported for total air phase concentrations (∑BDE-10: 9000-195,000pg/m 3 WEEE/vehicle facilities, 80-900pg/m 3 in incineration/sorting and landfill sites), but not for water leachate concentrations (e.g., ∑BDE-10: 15-3500ng/L in WEEE/Vehicle facilities and 1-250ng/L in landfill sites). Landfill leachate exhibited similar concentrations as WEEE/vehicle sorting and defragmenting facility leachate. To better account for concentrations in leachates at the different facilities, waste-water partitioning coefficients, K waste were measured (for the first time to our knowledge for flame retardants). WEEE and plastic waste had elevated K waste compared to other wastes, likely because flame retardants are directly added to these materials. The results of this study have implications for the development of strategies to reduce exposure and environmental emissions of flame retardants in waste and recycled products through improved waste management practices. Copyright © 2017. Published by Elsevier B.V.

  10. Phosphate flame retardants and novel brominated flame retardants in home-produced eggs from an e-waste recycling region in China.

    Science.gov (United States)

    Zheng, Xiaobo; Xu, Fuchao; Luo, Xiaojun; Mai, Bixian; Covaci, Adrian

    2016-05-01

    Phosphate flame retardants (PFRs) and novel brominated flame retardants (NBFRs) (2-ethylhexyl-2,3,4,5-tetrabromo-benzoate (EH-TBB) and bis-(2-ethylhexyl)-3,4,5,6-tetrabromo-phthalate (BEH-TEBP)) were measured in free-range chicken eggs from three e-waste recycling sites and a negative control site located in Guangdong province, Southern China. BEH-TEBP, tris-(chloroethyl)-phosphate (TCEP), tris-(chloropropyl)-phosphate (∑TCPP, two isomers) and tris-(1,3-dichloroisopropyl)-phosphate (TDCIPP) were detected in more than 50% of eggs samples with low concentrations. The median values of BEH-TEBP and total PFRs were 0.17-0.46 ng/g ww (wet weight) and 1.62-2.59 ng/g ww in eggs from the e-waste sites, respectively. The results indicate that EH-TBB, BEH-TEBP and PFRs are less persistent and bioaccumulative than polybrominated diphenyl ethers (PBDEs) in chicken eggs, and possibly also in other bio-matrices. Triphenyl phosphate (TPHP) were identified in albumen with higher frequencies, but at similar concentrations compared to yolk, while BEH-TEBP was mainly detected in yolk. The estimated daily intake (EDI) of BEH-TEBP and total PFRs from consumption of chicken eggs ranged from 0.03 to 0.09 and 0.32-0.52 ng/kg bw/day for adults, and 0.20-0.54 and 1.89-3.02 ng/kg bw/day for children in e-waste sites, respectively. Indoor dust ingestion seems to be a more important pathway for the intake of these FRs, while egg consumption is probably a more important exposure pathway for PBDEs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Intumescent flame retardant properties of graft copolymerized vinyl monomers onto cotton fabric

    Science.gov (United States)

    Rosace, G.; Colleoni, C.; Trovato, V.; Iacono, G.; Malucelli, G.

    2017-10-01

    In this paper, an intumescent flame retardant treatment, obtained by a combination of vinylphosphonic acid (VPA) and methacrylamide (MAA), was applied to cotton fabrics. In order to improve the cross-linking degree onto cellulose polymers, potassium persulfate was used as initiator of a radical polymerization technique. The application on cotton was carried out by padding, followed by drying and a curing treatment. The treated samples were characterized by SEM, TGA and FTIR-ATR analyses and tested in terms of flammability and washing fastness. The thermal and fire behavior of the treated fabrics was thoroughly investigated. The results clearly showed that the VPA/MAA coating was able to exert a protective action, giving rise to the formation of a stable char on the surface of textile fibers upon heating, hence improving the flame retardant performance of cotton. Horizontal flame spread tests confirmed that the coated fabrics achieved self-extinction, and the residues well preserved the original weave structure and fiber morphology; at variance, the uncoated fabric left only ashes. A remarkable weight loss was observed only after the first washing cycle, then the samples did not show any significant weight loss, hence confirming the durability of the self-extinguishing treatment, even after five laundering cycles.

  12. Novel Multifunctional Organic-Inorganic Hybrid Curing Agent with High Flame-Retardant Efficiency for Epoxy Resin.

    Science.gov (United States)

    Tan, Yi; Shao, Zhu-Bao; Chen, Xue-Fang; Long, Jia-Wei; Chen, Li; Wang, Yu-Zhong

    2015-08-19

    A novel multifunctional organic-inorganic hybrid was designed and prepared based on ammonium polyphosphate (APP) by cation exchange with diethylenetriamine (DETA), abbreviated as DETA-APP. Then DETA-APP was used as flame-retardant curing agent for epoxy resin (EP). Curing behavior, including the curing kinetic parameters, was investigated by differential scanning calorimetry (DSC) and X-ray photoelectron spectroscopy (XPS). The flame retardance and burning behavior of DETA-APP cured EP were also evaluated. The limiting oxygen index (LOI) value of DETA-APP/EP was enhanced to 30.5% with only 15 wt % of DETA-APP incorporated; and the UL-94 V-0 rating could be easily passed through with only 10 wt % of the hybrid. Compared with DETA/EP, the peak-heat release rate (PHRR), total heat release (THR), total smoke production (TSP), and peak-smoke production release (SPR) of DETA-APP/EP (15 wt % addition), obtained from cone calorimetry, were dropped by 68.3, 79.3, 79.0, and 30.0%, respectively, suggesting excellent flame-retardant and smoke suppression efficiency. The flame-retardant mechanism of DETA-APP/EP has been investigated comprehensively. The results of all the aforementioned studies distinctly confirmed that DETA-APP was an effective flame-retardant curing agent for EP.

  13. Flame-Retardant and Thermal Degradation Mechanism of Caged Phosphate Charring Agent with Melamine Pyrophosphate for Polypropylene

    Directory of Open Access Journals (Sweden)

    Xuejun Lai

    2015-01-01

    Full Text Available An efficient caged phosphate charring agent named PEPA was synthesized and combined with melamine pyrophosphate (MPP to flame-retard polypropylene (PP. The effects of MPP/PEPA on the flame retardancy and thermal degradation of PP were investigated by limiting oxygen index (LOI, vertical burning test (UL-94, cone calorimetric test (CCT, and thermogravimetric analysis (TGA. It was found that PEPA showed an outstanding synergistic effect with MPP in flame retardant PP. When the content of PEPA was 13.3 wt% and MPP was 6.7 wt%, the LOI value of the flame retardant PP was 33.0% and the UL-94 test was classed as a V-0 rating. Meanwhile, the peak heat release rate (PHRR, average heat release rate (AV-HRR, and average mass loss rate (AV-MLR of the mixture were significantly reduced. The flame-retardant and thermal degradation mechanism of MPP/PEPA was investigated by TGA, Fourier transform infrared spectroscopy (FTIR, TG-FTIR, and scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDXS. It revealed that MPP/PEPA could generate the triazine oligomer and phosphorus-containing compound radicals which changed the thermal degradation behavior of PP. Meanwhile, a compact and thermostable intumescent char was formed and covered on the matrix surface to prevent PP from degrading and burning.

  14. Influence of natural organic matter on the extraction efficiency of flame retardants from surface waters.

    Science.gov (United States)

    Gustavsson, Jakob; Ahrens, Lutz; Nguyen, Minh A; Josefsson, Sarah; Berggren Kleja, Dan; Wiberg, Karin

    2017-11-17

    The influence of natural organic matter (NOM) on the solid-phase extraction (SPE) efficiency was investigated for legacy and emerging flame retardants (FRs; n=26) in surface water. Three different groups of FRs were analyzed: polybrominated diphenyl ethers (PBDEs), halogenated flame retardants (HFRs), and organophosphorus flame retardants (OPFRs). In addition, five sorbents (Amberlite XAD-2, Amberlite IRA-743, Oasis HLB, Chromabond HR-P, and Chromabond HR-X) were evaluated for the extraction of FRs (n=33) in water, of which Oasis HLB eluted with dichloromethane and acetone:n-hexane (1:1, v/v) provided the highest overall recoveries. In subsequent NOM experiments, where FRs were extracted from water containing different NOM concentrations, both increased and decreased extraction efficiency with increasing NOM level were observed. Physicochemical and semi-empirical quantum chemistry properties were calculated for the FRs and used for analyzing relations between FRs. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) showed that the FRs separated into four different groups based on their properties. The FRs within each group responded similarly to increasing NOM, while differences in behavior were observed between the groups. This suggests that the structural properties of micropollutants highly influence NOM-FR interaction mechanisms. For instance, at high NOM levels, recoveries decreased substantially for FRs containing a moiety that can form strong hydrogen bonds (such as the double-bonded oxygen in e.g., OPFRs). Many of the compounds showed maximum extraction efficiency at higher levels of NOM. This suggests that binding of NOM to the sorbent and subsequent interaction between sorbent-bound NOM and FRs is an important mechanism for extraction of micropollutants from surface waters. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Mimicking of Estradiol Binding by Flame Retardants and Their Metabolites: A Crystallographic Analysis

    Science.gov (United States)

    Gosavi, Rajendrakumar A.; Knudsen, Gabriel A.; Birnbaum, Linda S.

    2013-01-01

    Background: Brominated flame retardants (BFRs), used in many types of consumer goods, are being studied because of concerns about possible health effects related to endocrine disruption, immunotoxicity, reproductive toxicity, and neurotoxicity. Tetrabromobisphenol A (TBBPA), the most widely used BFR, and human metabolites of certain congeners of polybrominated diphenyl ether (e.g., 3-OH-BDE-47) have been suggested to inhibit estrogen sulfotransferase, potentially affecting estrogen metabolism. Objectives: Our primary goal was to understand the structural mechanism for inhibition of the hormone-metabolizing enzyme estrogen sulfotransferase by certain BFRs. We also sought to understand various factors that facilitate the binding of flame retardants in the enzyme binding pocket. Methods: We used X-ray crystallography to obtain atomic detail of the binding modes of TBBPA and 3-OH-BDE-47 to estrogen sulfotransferase for comparison with binding of the endogenous substrate estradiol. Results: The crystal structures reveal how BFRs mimic estradiol binding as well as the various interactions between the compounds and protein residues that facilitate its binding. In addition, the structures provide insights into the ability of the sulfotransferase substrate binding pocket to accommodate a range of halogenated compounds that satisfy minimal structural criteria. Conclusions: Our results show how BFRs or their metabolites can bind to and inhibit a key hormone-metabolizing enzyme, potentially causing endocrine disruption. Citation: Gosavi RA, Knudsen GA, Birnbaum LS, Pedersen LC. 2013. Mimicking of estradiol binding by flame retardants and their metabolites: a crystallographic analysis. Environ Health Perspect 121:1194–1199; http://dx.doi.org/10.1289/ehp.1306902 PMID:23959441

  16. Multi-functional carbon microspheres with double shell layers for flame retardant poly (ethylene terephthalate)

    Science.gov (United States)

    Xue, Baoxia; Niu, Mei; Yang, Yongzhen; Bai, Jie; Song, Yinghao; Peng, Yun; Liu, Xuguang

    2018-03-01

    Carbon microspheres (CMSs) as a core material had been coated by two capsule walls: an inorganic material of magnesium hydroxide (MH) as inner shell layer and an organic material of poly (ethylene terephthalate) (PET) as outer shell layer. MH coating CMSs (MCMSs) were fabricated by liquid phase deposition method, then grafted 3-Aminopropyltriethoxysilane (APTS) to obtain the Si-MCMSs. Microencapsulated Si-MCMSs (PMCMSs) was prepared by in situ polymerization method. Morphology structure, dispersion, flame retardant and other properties of PMCMSs have been investigated. A series of PET blends were prepared by melt compounding. The results showed that MH and PET as two layers were coated on CMSs surface with the optimal thickness of about 70 nm. The PMCMSs owned better dispersion in PET matrix. Compared with MCMSs/PET composites, the mechanical property of PMCMSs/PET composites had significantly increased because of the strong interface binding force between PMCMSs and PET matrix. Moreover, PMCMSs was proved to be an effective flame retardant. For PMCMSs/PET with 2 wt% PMCMSs, the limiting oxygen index (LOI) value increased from 21.0% (pristine PET) to 27.2%, and the peak heat release rate (pk-HRR) decreased from 513.22 kW/m2 to 352.14 kW/m2. The decreased smoke production rate (SPR) and total smoke production (TSP) values demonstrated PMCMSs suppressed the smoke production. The increased Fire performance index (FPI) value illustrated PMCMSs significantly reduced the fire risk of PET. Overall, the two capsular walls endowed the PMCMSs/PET composites with good mechanical and flame-retardant properties.

  17. Emission behavior of hexabromocyclododecanes and polybrominated diphenyl ethers from flame-retardant-treated textiles.

    Science.gov (United States)

    Kajiwara, Natsuko; Takigami, Hidetaka

    2013-10-01

    To evaluate the emission behavior of hexabromocyclododecanes (HBCDs) and polybrominated diphenyl ethers (PBDEs) added to textile products as flame retardants, we used a small stainless steel container (7 cm i.d. × 5.5 cm height, ca. 210 cm(3)) to conduct emission tests on three upholstery textile samples at temperatures of 20, 40, 60, and 80 °C. The textile samples, which were intended for use in curtain manufacture and had been treated with either technical HBCD or technical DecaBDE, emitted HBCDs and PBDEs, including BDE 209, even at room temperature (20 °C), and the emission rates increased with increasing test temperature. These results indicate that flame-retardant-treated upholstery textiles have the potential to be major sources of brominated flame retardant contamination in indoor air and dust. The HBCD diastereomer emission profiles at the test temperatures of 20 and 40 °C were similar to the profiles of the original textile samples; in contrast, at the higher test temperatures, the proportion of α-HBCD was larger (up to 70% of the total HBCD emission) than in the original samples. At the higher test temperatures, the proportions of di- to hexa-BDEs in the emissions were clearly larger than in the original sample, suggesting that the textile products treated with technical DecaBDE could be a source of environmentally relevant PBDE congeners such as BDE 47, 99, and 100. The emission rates of HBCDs from the textiles were two orders of magnitude higher than those of PBDEs, suggesting that HBCDs volatilize more easily from textile products to the indoor environment than PBDEs.

  18. Low-smoke, halogenfree ship-offshore/onshore cables with improved flame retardance and fire resistance

    Science.gov (United States)

    Pedersen, J. R.; Holte, T. A.; Johansen, E.

    Cables with improved fire resistance and flame retardance have been developed. They will continue to function at least 3 hours even at temperatures up to 1000 C and do not propagate fire when tested according to IEC 332 part 3 1982, category A. Made with halogenfree materials they give off no corrosive gases and very little visible smoke in cases of fire. Cables are made for power, signal and instrument installations in hospitals, high rise buildings, railroad cars, subways, on board ship, oil rigs and oil production platforms. The offshore cables are specially constructed to withstand the rugged climatic conditions in the North Sea area.

  19. Durable flame retardant finish for silk fabric using boron hybrid silica sol

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Qiang-hua; Gu, Jiali; Chen, Guo-qiang [National Engineering Laboratory for Modern Silk, Soochow University (China); Xing, Tie-ling, E-mail: xingtieling@suda.edu.cn [National Engineering Laboratory for Modern Silk, Soochow University (China); Jiangsu HuaJia Group (China)

    2016-11-30

    Highlights: • Highly homogeneous boron hybrid silica sol flame retardant system was prepared through sol-gel method. • The silk samples treated and cross-linked by this hybrid sol and BTCA solution showed a higher limiting oxygen index (LOI) more than 31.0% and a better washing durability for more than 30 times washing. • The smoke suppression, combustion performance and thermal stability properties of the treated samples have a significant improvement. - Abstract: A hybrid silica sol was prepared via sol gel method using tetraethoxysilane (TEOS) as a precursor and boric acid (H{sub 3}BO{sub 3}) as flame retardant additive and then applied to silk fabric. In order to endow silk fabric with durable flame retardancy, 1,2,3,4-butanetetracarboxylic acid (BTCA) was used as cross-linking agent for the sake of strong linkage formation between the hybrid silica sol and silk fabric. The FT-IR and XPS analysis demonstrated the Si-O-B formation in the sol system, as well as the linkage between the sol and silk after the treatment. The limiting oxygen index (LOI) and smoke density test indicated good flame retardancy and smoke suppression of the treated silk fabrics. The micro calorimeter combustion (MCC) test and thermo gravimetric (TG) analysis showed that the treated samples had less weight loss in the high temperature and lower heat release rate when burning. The washing durability evaluation results indicated that there was a distinct improvement for the silk samples treated with BTCA even after 30 times washing. In addition, the influence of the processing order of BTCA and silica sol treatment on the limiting oxygen index (LOI) of the finished silk fabric was also investigated. And the results demonstrated that the sample treated with BTCA first and then with the silica sol exhibited better LOI value (32.3%) than that of the sample by the conversed treatment order. Moreover the tensile property of treated samples was nearly unchanged, but the handle of sol treated

  20. Aluminium trihydroxide in combination with ammonium polyphosphate as flame retardants for unsaturated polyester resin

    Directory of Open Access Journals (Sweden)

    2009-11-01

    Full Text Available The thermal and reaction to fire characteristics of a flame retardant unsaturated polyester (UP ternary system are presented here. Thermal gravimetric analysis showed an improved thermal stability between 200–600°C with the addition of ammonium polyphosphate (APP and aluminium trihydroxide (ATH formulation. Cone calorimetry tests indicated that ATH is more efficient than calcium carbonate at delaying the ignition time, lowering the carbon monoxide yield and lowering the peak heat release (PHRR. However the addition of APP and ATH to the formulation failed to demonstrate any significant synergistic effect at reducing the PHRR.

  1. The Effect of Mg(OH2 Nanoparticles on the Thermal Stability and Flame Retardancy of Paraloid Nanocomposites

    Directory of Open Access Journals (Sweden)

    H. R. Momenian

    2014-01-01

    Full Text Available Paraloid-Mg(OH2 nanocomposites were synthesized via sonochemical method. Nanostructures were characterized by XRD and SEM. Thermal stability behavior of paraloid filled with magnesium hydroxide was investigated by thermogravimetric analysis (TGA. The influence of Mg(OH2 nanostructures on the flame retardancy of the paraloid matrix was studied using UL-94 analysis. Our results show that the Mg(OH2 nanostructure can enhance the flame retardant property of the paraloid matrix. The enhancement of flame retardancy of nanocomposite is due to endothermic decomposition of Mg(OH2 that absorbs energy and simultaneously releases of water (dilutes combustible gases. Photo-catalytic activity of the nanoparticles was evaluated by monitoring the degradation of methyl orange (MeO in an aqueous solution.

  2. A Fast Method for Synthesis Magnesium Hydroxide Nanoparticles, Thermal Stable and Flame Retardant Poly vinyl alcohol Nanocomposite

    Directory of Open Access Journals (Sweden)

    M. Yousefi

    2014-07-01

    Full Text Available Magnesium hydroxide nanostructures as an effective flame retardant were synthesized by a facile and rapid microwave reaction. The effect of different surfactants such as cationic, anionic and polymeric on the morphology of magnesium hydroxide nanostructures was investigated. Nanostructures were characterized by X-ray diffraction (XRD, scanning electron microscopy (SEM and Fourier transform infrared (FT-IR spectroscopy. The influence of Mg(OH2 nanostructures on the thermal stability and flame retardancy of the poly vinyl alcohol (PVA matrix was studied using thermogravimetric analysis (TGA and UL-94 respectively. Thermal decomposition of the nanocomposites shift towards higher temperature in the presence of Mg(OH2 nanostructures. The enhancement of thermal stability and flame retardancy of nanocomposites is due to the endothermic decomposition of Mg(OH2 and release of water which dilutes combustible gases.

  3. Legacy and alternative halogenated flame retardants in human milk in Europe: Implications for children's health.

    Science.gov (United States)

    Čechová, Eliška; Vojta, Šimon; Kukučka, Petr; Kočan, Anton; Trnovec, Tomáš; Murínová, Ľubica Palkovičová; de Cock, Marijke; van de Bor, Margot; Askevold, Joakim; Eggesbø, Merete; Scheringer, Martin

    2017-11-01

    In this study, 10 polybrominated diphenyl ethers (PBDEs) and 19 alternative halogenated flame retardants (AFRs) were determined in >450 human milk samples across three European countries, representing northern, western and eastern Europe. This study provides first insights into the occurrence of selected AFRs in mother milk samples and compares them among three European countries. Sums of median concentrations of the most frequently detected PBDEs were 2.16, 0.88 and 0.45ngg -1 lipid weight (lw) in Norway, the Netherlands and Slovakia, respectively. The sum of the concentrations of AFRs ranged from 0.14 to 0.25ngg -1 lw in all countries, which was 2 to 15 times less compared to Σ 7 PBDEs. The Penta-BDE replacement, bis(2-ethylhexyl) tetrabromophthalate, BEH-TEBP, was present at the greatest concentrations of any of the AFRs and in some samples exceeded concentrations of BDE 47 and BDE 153. Four AFRs including bromobenzenes (hexabromobenzene, pentabromobenzene, pentabromotoluene) and another Penta-BDE replacement (2-ethylhexyl-2,3,4,5-tetrabromobenzoate, EH-TBB) were detected in >42% of all human milk samples. Because of the potential developmental neurotoxicity of the halogenated flame retardants, infant dietary intakes via breastfeeding were estimated; in four cases the intakes of BDE 47 exceeded the reference dose indicating that the present concentrations may pose a risk for children. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Raman spectroscopy based identification of flame retardants in consumer products using an acquired reference spectral library.

    Science.gov (United States)

    Ghosal, Sutapa; Fang, Huiting

    2015-01-01

    Flame retardants (FRs), a class of commonly used chemical additives in consumer products such as polyurethane foams, are well known for their persistence in the environment, bioaccumulation and potential toxicity [1]. In order to address the potential health concerns and environmental impacts associated with the wide-spread use these chemicals, it is essential to identify them efficiently in the environment and consumer products. Raman spectroscopy (RS) offers an attractive option for the non-invasive, in-situ identification of flame retardants in a variety of sample formats [2-4]. RS based chemical identification relies on the availability of spectral libraries for identification through spectral matching with reference chemicals. Here we present the application of Raman spectroscopy for identifying FR additives in select consumer products using an acquired spectral library of commonly used FRs. The RS based method described here enables simultaneous identification of multiple components within a sample, which can offer important insights into the sources of FR contamination, in addition to identification of the FR component itself. The availability of Raman spectral library of commercially used FRs, such as the one presented here, will facilitate the identification of these chemicals in consumer products. Published by Elsevier B.V.

  5. Flame Retardancy of Carbon Fibre Reinforced Sorbitol Based Bioepoxy Composites with Phosphorus-Containing Additives.

    Science.gov (United States)

    Toldy, Andrea; Niedermann, Péter; Pomázi, Ákos; Marosi, György; Szolnoki, Beáta

    2017-04-27

    Carbon fibre reinforced flame-retarded bioepoxy composites were prepared from commercially available sorbitol polyglycidyl ether (SPE) cured with cycloaliphatic amine hardener. Samples containing 1, 2, and 3% phosphorus (P) were prepared using additive type flame retardants (FRs) resorcinol bis(diphenyl phosphate) (RDP), ammonium polyphosphate (APP), and their combinations. The fire performance of the composites was investigated by limiting oxygen index (LOI), UL-94 tests, and mass loss calorimetry. The effect of FRs on the glass transition temperature, and storage modulus was evaluated by dynamic mechanical analysis (DMA), while the mechanical performance was investigated by tensile, bending, and interlaminar shear measurements, as well as by Charpy impact test. In formulations containing both FRs, the presence of RDP, acting mainly in gas phase, ensured balanced gas and solid-phase mechanism leading to best overall fire performance. APP advantageously compensated the plasticizing (storage modulus and glass transition temperature decreasing) effect of RDP in combined formulations; furthermore, it led to increased tensile strength and Charpy impact energy.

  6. Accumulation of flame retardants in paired eggs and plasma of bald eagles.

    Science.gov (United States)

    Guo, Jiehong; Simon, Kendall; Romanak, Kevin; Bowerman, William; Venier, Marta

    2018-03-05

    In this study, we measured the concentrations of 58 flame retardants (and related compounds) in bald eagle (Haliaeetus leucocephalus) egg and plasma samples from the Michigan. These analytes include polybrominated diphenyl ethers (PBDEs), novel flame retardants (nFRs), Dechlorane-related compounds (Decs), and organophosphate esters (OPEs). A total of 24 paired eaglet plasma and egg samples were collected from inland (IN, N = 13) and the Great Lakes (GL, N = 11) breeding areas from 2000 to 2012. PBDEs were the most abundant chemical group with a geometric mean of 181 ng/g wet weight (ww) in egg and 5.31 ng/g ww in plasma. Decs were barely found in plasma samples, but they were frequently found in eggs (geometric mean 23.5 ng/g ww). OPE levels were comparable to those of PBDEs in the plasma but lower than those of PBDEs in eggs. Dec and PBDE concentrations were significantly higher in GL than in IN (p eagle egg and plasma concentrations from Lake Superior and Huron were one to three orders of magnitude higher than concentrations measured in composite lake trout (Salvelinus namaycush) from the same lake, implying that they biomagnify in the environment. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Preparation of novel flame-retardant organoclay and its application to natural rubber composites

    Science.gov (United States)

    Zhang, Guangjian; Wang, Jincheng

    2018-04-01

    In this study, a novel type of flame-retardant montmorillonite (MMT) was prepared using a new approach to obtain highly branched polymer chains. First, MMT was modified using a small liquid crystal molecule comprising N,N,N tris(2-hydroxyethyl)sbnd N-dodecylammonium bromide and organic MMT (OMMT) was obtained. Next, three generations of dendrimer-modified organoclay comprising DOMMT-1, DOMMT-2, and DOMMT-3 were successfully prepared using OMMT and branching units of ethylenediamine and methyl acrylate. Their chemical structures were characterized and confirmed by different methods. The DOMMT organoclay was used in the preparation of natural rubber (NR) composites. The tensile strength and elongation at breakage for NR/DOMMT-10 were 17.3 MPa and 697%, respectively, which were about 13.8% and 10.8% higher, respectively, compared with that for the pure NR. After the addition of DOMMT, the horizontal burning time increased by about 69% and the thermal stability was also improved. We also propose a possible flame-retardant and reinforcing mechanism for this novel organoclay in an NR matrix.

  8. Selected chlorobornanes, polychlorinated naphthalenes and brominated flame retardants in Bjornoya (Bear Island) freshwater biota

    International Nuclear Information System (INIS)

    Evenset, Anita; Christensen, Guttorm N.; Kallenborn, Roland

    2005-01-01

    Levels of selected sparsely investigated persistent organic pollutants (POPs) have been measured in organisms from two Arctic lakes on Bjornoya (Bear Island). Elevated levels of chlorobornanes (CHBs) (up to 46.7 ng/g wet weight=ww), polybrominated diphenyl ethers (PBDEs) (up to 27.2 ng/g ww), polybrominated biphenyls (PBBs) (up to 1.1 ng/g ww) and polychlorinated naphthalenes (PCNs, only 4 congeners) (up to 62.7 pg/g ww), were measured in biota from Lake Ellasjoen. In Lake Oyangen, located only 5 km north of Ellasjoen, levels of these contaminants were significantly lower. δ 15 N-values were 7-10%o higher in organisms from Ellasjoen as compared to Oyangen. This is attributed to biological inputs related to seabird activities. The present study illustrates that contaminants such as CHBs, brominated flame retardants and PCNs accumulate in the Ellasjoen food web in a manner similar to PCBs and conventional organochlorine pesticides. Transport mechanisms that control PCB and DDT distributions, i.e. atmospheric long-range transport and biotransport by seabirds, are also relevant for the contaminants investigated in the present study. - Elevate levels of chlorobornanes, polychlorinated naphthalenes and brominated flame retardants have been measured in biota from a Norwegian Arctic lake

  9. Selected chlorobornanes, polychlorinated naphthalenes and brominated flame retardants in Bjornoya (Bear Island) freshwater biota

    Energy Technology Data Exchange (ETDEWEB)

    Evenset, Anita [Akvaplan-niva, Polar Environmental Centre, N-9296 Tromso (Norway)]. E-mail: ae@akvaplan.niva.no; Christensen, Guttorm N. [Akvaplan-niva, Polar Environmental Centre, N-9296 Tromso (Norway); Kallenborn, Roland [Norwegian Institute for Air Research, P.O. Box 100, N-2027 Kjeller (Norway)

    2005-08-15

    Levels of selected sparsely investigated persistent organic pollutants (POPs) have been measured in organisms from two Arctic lakes on Bjornoya (Bear Island). Elevated levels of chlorobornanes (CHBs) (up to 46.7 ng/g wet weight=ww), polybrominated diphenyl ethers (PBDEs) (up to 27.2 ng/g ww), polybrominated biphenyls (PBBs) (up to 1.1 ng/g ww) and polychlorinated naphthalenes (PCNs, only 4 congeners) (up to 62.7 pg/g ww), were measured in biota from Lake Ellasjoen. In Lake Oyangen, located only 5 km north of Ellasjoen, levels of these contaminants were significantly lower. {delta}{sup 15}N-values were 7-10%o higher in organisms from Ellasjoen as compared to Oyangen. This is attributed to biological inputs related to seabird activities. The present study illustrates that contaminants such as CHBs, brominated flame retardants and PCNs accumulate in the Ellasjoen food web in a manner similar to PCBs and conventional organochlorine pesticides. Transport mechanisms that control PCB and DDT distributions, i.e. atmospheric long-range transport and biotransport by seabirds, are also relevant for the contaminants investigated in the present study. - Elevate levels of chlorobornanes, polychlorinated naphthalenes and brominated flame retardants have been measured in biota from a Norwegian Arctic lake.

  10. Potential Role of Pet Cats As a Sentinel Species for Human Exposure to Flame Retardants

    Directory of Open Access Journals (Sweden)

    Luis A. Henríquez-Hernández

    2017-05-01

    Full Text Available Flame retardants are a wide group of chemicals used by the industry to avoid combustion of materials. These substances are commonly found in plastics, electronic equipment, fabrics, and in many other everyday articles. Subsequently, ubiquitous environmental contamination by these common chemical is frequently reported. In the present study, we have evaluated the level of exposure to polychlorinated biphenyls (PCBs, brominated diphenyl ethers (BDEs, and organophosphorous flame retardants (OPFRs in pet cats through the analysis of their serum. We also analyzed the level exposure to such chemicals in a series of 20 cat owners, trying to disclose the role of pet cats as sentinel species of human exposure to FRs. Our results showed that PCBs, banned 40 years ago, showed the lowest levels of exposure, followed by BDEs—banned recently. Congeners PCB-138 and PCB-180 were detected in ≥50% of the series, while BDE-47 was detected in near 90% of the pet cats. On the other hand, the highest levels were that of OPFRs, whose pattern of detection was similar to that observed in humans, thus suggesting a potential role of cats as a sentinel species for human exposure to these currently used FRs. Six out of 11 OPFRs determined [2-ethylhexyldiphenyl phosphate, tributylphosphate, triisobutylphosphate, triphenylphosphate, tris (2-chloroethyl phosphate, and tris (2-chloroisopropyl phosphate] were detected in 100% of the samples. It will be interesting to perform future studied aimed to elucidating the potential toxicological effects of these highly detected chemicals both, in cats and humans.

  11. Occurrence of halogenated flame retardants in commercial seafood species available in European markets

    DEFF Research Database (Denmark)

    Aznar-Alemany, Òscar; Trabalón, Laura; Jacobs, Silke

    2017-01-01

    PBDEs (congeners 28, 47, 99, 100, 153, 154, 183, 209), HBCD (α, β, γ), emerging brominated flame retardants (PBEB, HBB and DBDPE), dechloranes (Dec 602, 603, 604, syn- and anti-DP), TBBPA, 2,4,6-TBP and MeO-PBDEs (8 congeners) were analysed in commercial seafood samples from European countries....... Levels were similar to literature and above the environmental quality standards (EQS) limit of the Directive 2013/39/EU for PBDEs. Contaminants were found in 90.5% of the seafood samples at n. d.-356 ng/g lw (n. d.-41.1 ng/g ww). DBDPE was not detected and 2,4,6-TBP was detected only in mussels......, but at levels comparable to those of PBDEs. Mussel and seabream were the most contaminated species and the Mediterranean Sea (FAO Fishing Area 37) was the most contaminated location. The risk assessment revealed that there was no health risk related to the exposure to brominated flame retardants via seafood...

  12. Flame Retardancy of Carbon Fibre Reinforced Sorbitol Based Bioepoxy Composites with Phosphorus-Containing Additives

    Directory of Open Access Journals (Sweden)

    Andrea Toldy

    2017-04-01

    Full Text Available Carbon fibre reinforced flame-retarded bioepoxy composites were prepared from commercially available sorbitol polyglycidyl ether (SPE cured with cycloaliphatic amine hardener. Samples containing 1, 2, and 3% phosphorus (P were prepared using additive type flame retardants (FRs resorcinol bis(diphenyl phosphate (RDP, ammonium polyphosphate (APP, and their combinations. The fire performance of the composites was investigated by limiting oxygen index (LOI, UL-94 tests, and mass loss calorimetry. The effect of FRs on the glass transition temperature, and storage modulus was evaluated by dynamic mechanical analysis (DMA, while the mechanical performance was investigated by tensile, bending, and interlaminar shear measurements, as well as by Charpy impact test. In formulations containing both FRs, the presence of RDP, acting mainly in gas phase, ensured balanced gas and solid-phase mechanism leading to best overall fire performance. APP advantageously compensated the plasticizing (storage modulus and glass transition temperature decreasing effect of RDP in combined formulations; furthermore, it led to increased tensile strength and Charpy impact energy.

  13. Flame Retardancy of Sorbitol Based Bioepoxy via Combined Solid and Gas Phase Action

    Directory of Open Access Journals (Sweden)

    Beáta Szolnoki

    2016-08-01

    Full Text Available Flame-retarded bioepoxy resins were prepared with the application of commercially available sorbitol polyglycidyl ether (SPE. The additive-type flame retardancy of the cycloaliphatic amine-cured SPE was investigated. Three-percent phosphorus (P-containing samples were prepared with the application of the liquid resorcinol bis(diphenyl phosphate (RDP, the solid ammonium polyphosphate (APP, and by combining them. Synergistic effect was found between the inorganic APP and the organophosphorus RDP, when applied in combination: formulations applying RDP or APP alone showed increased limiting oxygen index (LOI values, however, their UL-94 standard ratings remained HB. When the same amount of P originated from the two additives, V-0, self-extinguishing rating and LOI value of 34% (v/v was reached. By the combined approach the heat release rate of SPE could be lowered by approximately 60%. The assumed balanced solid and gas phase mechanism was confirmed by thermogravimetric analysis, Fourier transform infrared spectrometry (FTIR analysis (of the gases formed during laser pyrolysis, attenuated total reflection-infrared spectrometry (ATR-IR analysis (of the charred residues, as well as by mechanical testing (of the char obtained after combustion.

  14. Synthesis and carbonization chemistry of a phosphorous–nitrogen based intumescent flame retardant

    International Nuclear Information System (INIS)

    Ma, Haiyun; Fang, Zhengping

    2012-01-01

    Graphical abstract: The carbonization chemistry and mechanism of a novel synthesized intumescent flame retardant. The final chars showed a complex P-O-Ph and aromatic/graphitic structure containing architecture. Highlights: ► The IFR synthesized is polymeric and has high molecular weight. ► The IFR has a higher thermal stability than most of the commercial IFRs. ► The final chars of IFR showed a complex P-O-Ph and aromatic/graphitic structure. - Abstract: In this work, a polymeric phosphorous–nitrogen containing intumescent flame retardant, named poly(diaminodiphenyl methane spirocyclic pentaerythritol bisphosphonate) (PDSPB), was synthesized. The carbonization chemistry was investigated. FTIR and 1 H NMR were used to confirm the chemical structure of PDSPB. Thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), in situ FTIR and energy dispersive X-ray (EDX) were used to investigate and monitor the chemical structural changes during thermal degradation. PDSPB demonstrated a three-step degradation behavior. PDSPB oligomers continuously polymerized and generated a higher macromolecular weight during the first step (200–250 °C). The phosphate ester bonds were broken down and phosphoric acid was released which dehydrated the carbon source to form chars during the second step (280–320 °C). The residues will be further degraded and form final chars during the final weight loss step (400–450 °C). The final chars showed a complex P-O-Ph and aromatic/graphitic structure containing architecture.

  15. Are some "safer alternatives" hazardous as PBTs? The case study of new flame retardants.

    Science.gov (United States)

    Gramatica, Paola; Cassani, Stefano; Sangion, Alessandro

    2016-04-05

    Some brominated flame retardants (BFRs), as PBDEs, are persistent, bioaccumulative, toxic (PBT) and are restricted/prohibited under various legislations. They are replaced by "safer" flame retardants (FRs), such as new BFRs or organophosphorous compounds. However, informations on the PBT behaviour of these substitutes are often lacking. The PBT assessment is required by the REACH regulation and the PBT chemicals should be subjected to authorization. Several new FRs, proposed and already used as safer alternatives to PBDEs, are here screened by the cumulative PBT Index model, implemented in QSARINS (QSAR-Insubria), new software for the development/validation of QSAR models. The results, obtained directly from the chemical structure for the three studied characteristics altogether, were compared with those from the US-EPA PBT Profiler: the two different approaches are in good agreement, supporting the utility of a consensus approach in these screenings. A priority list of the most harmful FRs, predicted in agreement by the two modelling tools, has been proposed, highlighting that some supposed "safer alternatives" are detected as intrinsically hazardous for their PBT properties. This study also shows that the PBT Index could be a valid tool to evaluate appropriate and safer substitutes, a priori from the chemical design, in a benign by design approach, avoiding unnecessary synthesis and tests. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Single- and Multiwalled Carbon Nanotubes with Phosphorus Based Flame Retardants for Textiles

    Directory of Open Access Journals (Sweden)

    D. Wesolek

    2014-01-01

    Full Text Available Due to growing popularity of composites, modification methods to obtain the best properties are searched for. The aim of the study is to reduce the flammability of textile materials using nanocomposite polymer back-coating. Different types of carbon nanotubes (single- and multiwalled and different phosphorus flame retardants (ammonium polyphosphates and melamine polyphosphate were introduced into the resin and then the fabrics were covered by the obtained composites. Homogeneous dispersion of multiwalled carbon nanotubes in the polyurethane resin was obtained by sonification, which was confirmed by scanning electron microscopy. Flammability tests of fabrics coated by modified polyurethane resin were carried out using pyrolysis combustion flow calorimeter (PCFC and thermal stability of textiles was evaluated. Also, organoleptic estimation of coatings was conducted (flexibility and fragility. The use of polymer nanocomposites with phophorus flame retardants as a back-coating for textiles effectively reduces flammability and improves thermal stability of the fabric. Furthermore, the synergistic effect beetwen carbon nanotubes and phosphorous compound occurs. The resulting coatings are flexible and do not crack or change the feel of fabrics.

  17. Inhibition Effect of Phosphorus Flame Retardants on the Fire Disasters Induced by Spontaneous Combustion of Coal

    Directory of Open Access Journals (Sweden)

    Yibo Tang

    2017-01-01

    Full Text Available Coal spontaneous combustion (CSC generally induces fire disasters in underground mines, thus causing serious casualties, environmental pollution, and property loss around the world. By using six P-containing additives to process three typical coal samples, this study investigated the variations of the self-ignition characteristics of the coal samples before and after treatment. The analysis was performed by combining thermogravimetric analysis/differential scanning calorimetry (TG/DSC Fourier transform infrared spectrometer (FTIR and low temperature oxidation. Experimental results showed that P-containing inhibitors could effectively restrain the heat emitted in the combustion of coal samples and therefore the ignition temperature of the coal samples was delayed at varying degrees. The combustion rate of the coal samples was reduced as well. At the temperatures ranging from 50°C to 150°C, the activation energy of the coal samples after the treatment was found to increase, which indicated that the coal samples were more difficult to be oxidized. After being treated with phosphorus flame retardants (PFRs, the content of several active groups represented by the C-O structure in the three coal samples was proved to be obviously changed. This suggested that PFRs could significantly inhibit the content of CO generated by the low temperature oxidation of coal, and the flame-retardant efficiency grew with the increasing temperature. At 200°C, the maximal inhibition efficiency reached approximately 85%.

  18. Occurrence of halogenated flame retardants in commercial seafood species available in European markets.

    Science.gov (United States)

    Aznar-Alemany, Òscar; Trabalón, Laura; Jacobs, Silke; Barbosa, Vera Liane; Tejedor, Margarita Fernández; Granby, Kit; Kwadijk, Christiaan; Cunha, Sara C; Ferrari, Federico; Vandermeersch, Griet; Sioen, Isabelle; Verbeke, Wim; Vilavert, Lolita; Domingo, José L; Eljarrat, Ethel; Barceló, Damià

    2017-06-01

    PBDEs (congeners 28, 47, 99, 100, 153, 154, 183, 209), HBCD (α, β, γ), emerging brominated flame retardants (PBEB, HBB and DBDPE), dechloranes (Dec 602, 603, 604, syn- and anti-DP), TBBPA, 2,4,6-TBP and MeO-PBDEs (8 congeners) were analysed in commercial seafood samples from European countries. Levels were similar to literature and above the environmental quality standards (EQS) limit of the Directive 2013/39/EU for PBDEs. Contaminants were found in 90.5% of the seafood samples at n. d.-356 ng/g lw (n. d.-41.1 ng/g ww). DBDPE was not detected and 2,4,6-TBP was detected only in mussels, but at levels comparable to those of PBDEs. Mussel and seabream were the most contaminated species and the Mediterranean Sea (FAO Fishing Area 37) was the most contaminated location. The risk assessment revealed that there was no health risk related to the exposure to brominated flame retardants via seafood consumption. However, a refined risk assessment for BDE-99 is of interest in the future. Moreover, the cooking process concentrated PBDEs and HBB. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Solidifying process and flame retardancy of epoxy resin cured with boron-containing phenolic resin

    Science.gov (United States)

    Deng, Peng; Shi, Yan; Liu, Yuansen; Liu, Yuan; Wang, Qi

    2018-01-01

    For the sake of improving the charring performance and flame retardancy of epoxy resin (EP), boron-containing phenolic resin (BPR) instead of a conventional curing agent, linear phenolic resin (LPR) was employed to cure EP. Of several possible chemical structures for BPR, the existence of benzyl hydroxy groups in BPR chains has been confirmed using 1H nuclear magnetic resonance spectroscopy. The resonance of these groups may reasonably explain the higher curing reactivity of BPR-cured EP than that of LPR-cured EP. Thermogravimetric analysis, observation of the morphologies of the char residues and X-ray photoelectron spectroscopic were performed to characterize the charring process. Due to the presence of B2O3 produced on the char surface from decomposition of phenyl borates and the facile high self-crosslinking reaction of BPR, a more continuous and stronger char barrier was formed for BPR-cured EP compared to that for the LPR-cured EP system. Therefore the former exhibited much better flame retardancy. In addition, BPR-cured EP also displayed better dynamic mechanical properties, than those observed for LPR-cured EP. It is not subject to the significant lowering the glass transition temperature of the polymer which accompanies curing with LPR. This suggests that BPR cured resin may meet the requirement for utilization at high temperature.

  20. Flame retardant and hydrophobic coatings on cotton fabrics via sol-gel and self-assembly techniques.

    Science.gov (United States)

    Zhang, Dongqiao; Williams, Brandon L; Shrestha, Saral B; Nasir, Zain; Becher, Elaina M; Lofink, Benjamin J; Santos, Victor H; Patel, Harsh; Peng, Xiaohong; Sun, Luyi

    2017-11-01

    Nanocoatings consisting of ammonium polyphosphate (APP), sodium montmorillonite (MMT), and vinyltrimethoxysilane (VTMS) were prepared via self-assembly and in situ sol-gel techniques and applied onto cotton fabrics to achieve both flame retardancy and hydrophobicity. The impacts of APP concentration on the hydrophobicity and fire resistance of the coated fabrics were investigated. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) characterization results verified the hydrolysis-condensation reaction of VTMS and the formation of Si-O-Si network structure. X-ray diffraction (XRD) proved the formation of a layered structure based on MMT nanosheets in the coatings. Both vertical flame test (VFT), limiting oxygen index (LOI), thermogravimetric analysis (TGA) and microscale combustion calorimeter (MCC) characterization were conducted to evaluate the flame retardancy, thermostability and heat release behavior of the coated cotton fabrics, respectively. The results suggested that a higher concentration of APP is beneficial for both hydrophobicity and flame retardancy of the coated substrates. Overall, our research provides a facile and very effective approach to prepare flame retardant and hydrophobic multifunctional coating for cotton fabric and other substrates. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Layer-by-Layer Assembly of Halogen-Free Polymeric Materials on Nylon/Cotton Blend for Flame Retardant Applications

    Science.gov (United States)

    2015-07-01

    D6413M 13b (http://enter- prise2.astm.org/DOWNLOAD/D6413.143487-1. pdf ). 28. Hanoosh WS, Abdelrazaq EM. Polydimethyl siloxane toughened epoxy resins ...on the decomposition and fire behavior of flame-retarded epoxy resin composites. Polymer 2006; 47:8495–8508. DOI: 10.1016/j.polymer.2006.10.022. 7...Hsiue GH, Wang WJ, Chang FC. Synthesis, characterization, thermal and flame-retardant properties of silicon based epoxy resins . Journal of Applied

  2. Study of the Thermal Properties and the Fire Performance of Flame Retardant-Organic PCM in Bulk Form.

    Science.gov (United States)

    Palacios, Anabel; De Gracia, Alvaro; Haurie, Laia; Cabeza, Luisa F; Fernández, A Inés; Barreneche, Camila

    2018-01-12

    The implementation of organic phase change materials (PCMs) in several applications such as heating and cooling or building comfort is an important target in thermal energy storage (TES). However, one of the major drawbacks of organic PCMs implementation is flammability. The addition of flame retardants to PCMs or shape-stabilized PCMs is one of the approaches to address this problem and improve their final deployment in the building material sector. In this study, the most common organic PCM, Paraffin RT-21, and fatty acids mixtures of capric acid (CA), myristic acid (MA), and palmitic acid (PA) in bulk, were tested to improve their fire reaction. Several flame retardants, such as ammonium phosphate, melamine phosphate, hydromagnesite, magnesium hydroxide, and aluminum hydroxide, were tested. The properties of the improved PCM with flame retardants were characterized by thermogravimetric analyses (TGA), the dripping test, and differential scanning calorimetry (DSC). The results for the dripping test show that fire retardancy was considerably enhanced by the addition of hydromagnesite (50 wt %) and magnesium hydroxide (50 wt %) in fatty acids mixtures. This will help the final implementation of these enhanced PCMs in building sector. The influence of the addition of flame retardants on the melting enthalpy and temperatures of PCMs has been evaluated.

  3. Study of the Thermal Properties and the Fire Performance of Flame Retardant-Organic PCM in Bulk Form

    Directory of Open Access Journals (Sweden)

    Anabel Palacios

    2018-01-01

    Full Text Available The implementation of organic phase change materials (PCMs in several applications such as heating and cooling or building comfort is an important target in thermal energy storage (TES. However, one of the major drawbacks of organic PCMs implementation is flammability. The addition of flame retardants to PCMs or shape-stabilized PCMs is one of the approaches to address this problem and improve their final deployment in the building material sector. In this study, the most common organic PCM, Paraffin RT-21, and fatty acids mixtures of capric acid (CA, myristic acid (MA, and palmitic acid (PA in bulk, were tested to improve their fire reaction. Several flame retardants, such as ammonium phosphate, melamine phosphate, hydromagnesite, magnesium hydroxide, and aluminum hydroxide, were tested. The properties of the improved PCM with flame retardants were characterized by thermogravimetric analyses (TGA, the dripping test, and differential scanning calorimetry (DSC. The results for the dripping test show that fire retardancy was considerably enhanced by the addition of hydromagnesite (50 wt % and magnesium hydroxide (50 wt % in fatty acids mixtures. This will help the final implementation of these enhanced PCMs in building sector. The influence of the addition of flame retardants on the melting enthalpy and temperatures of PCMs has been evaluated.

  4. Effects of neonatal exposure to the flame retardant tetrabromobisphenol-A, aluminum diethylphosphinate or zinc stannate on long-term potentiation and synaptic protein levels in mice

    NARCIS (Netherlands)

    Hendriks, Hester; Koolen, Lucas; Dingemans, Milou; Viberg, Henrik; Lee, Iwa; Leonards, P.E.G.; Ramakers, G.M.J.; Westerink, Remco

    2014-01-01

    Brominated flame retardants such as tetrabromobisphenol-A (TBBPA) may exert (developmental) neurotoxic effects. However, data on (neuro)toxicity of halogen-free flame retardants (HFFRs) are scarce. Recent in vitro studies indicated a high neurotoxic potential for some HFFRs, e.g., zinc stannate

  5. Effects of neonatal exposure to the flame retardant tetrabromobisphenol-A, aluminum diethylphosphinate or zinc stannate on long-term potentiation and synaptic protein levels in mice

    NARCIS (Netherlands)

    Hendriks, Hester S.; Koolen, Lucas A. E.; Dingemans, Milou M. L.; Viberg, Henrik; Lee, Iwa; Leonards, Pim E. G.; Ramakers, Geert M. J.; Westerink, Remco H. S.

    2015-01-01

    Brominated flame retardants such as tetrabromobisphenol-A (TBBPA) may exert (developmental) neurotoxic effects. However, data on (neuro)toxicity of halogen-free flame retardants (HFFRs) are scarce. Recent in vitro studies indicated a high neurotoxic potential for some HFFRs, e.g., zinc stannate

  6. Analysis of two alternative organophosphorus flame retardants in electronic and plastic consumer products: resorcinol bis-(diphenylphosphate) (PBDPP) and bisphenol A bis (diphenylphosphate) (BPA-BDPP)

    NARCIS (Netherlands)

    Ballesteros Gomez, A.M.; Brandsma, S.H.; de Boer, J.; Leonards, P.E.G.

    2014-01-01

    Following the phase-out of polybrominated diphenyl ethers (PBDEs), organophosphorus flame retardants (PFRs) are increasingly used as alternative flame retardants in many products. Data on the presence of two alternative PFRs in consumer products, resorcinol bis (diphenylphosphate) (PBDPP or RDP) and

  7. Thermal Stability, Combustion Behavior, and Mechanical Property in a Flame-Retardant Polypropylene System

    Directory of Open Access Journals (Sweden)

    Lili Wang

    2017-01-01

    Full Text Available In order to comprehensively improve the strength, toughness, flame retardancy, smoke suppression, and thermal stability of polypropylene (PP, layered double hydroxide (LDH Ni0.2Mg2.8Al–LDH was synthesized by a coprecipitation method coupled with the microwave-hydrothermal treatment. The X-ray diffraction (XRD, morphology, mechanical, thermal, and fire properties for PP composites containing 1 wt %–20 wt % Ni0.2Mg2.8Al–LDH were investigated. The cone calorimeter tests confirm that the peak heat release rate (pk–HRR of PP–20%LDH was decreased to 500 kW/m2 from the 1057 kW/m2 of PP. The pk–HRR, average mass loss rate (AMLR and effective heat of combustion (EHC analysis indicates that the condensed phase fire retardant mechanism of Ni0.2Mg2.8Al–LDH in the composites. The production rate and mean release yield of CO for composites gradually decrease as Ni0.2Mg2.8Al–LDH increases in the PP matrix. Thermal analysis indicates that the decomposition temperature for PP–5%LDH and PP–10%LDH is 34 °C higher than that of the pure PP. The mechanical tests reveal that the tensile strength of PP–1%LDH is 7.9 MPa higher than that of the pure PP. Furthermore, the elongation at break of PP–10%LDH is 361% higher than PP. In this work, the synthetic LDH Ni0.2Mg2.8Al–LDH can be used as a flame retardant, smoke suppressant, thermal stabilizer, reinforcing, and toughening agent of PP products.

  8. Bioaccumulation and biomagnification of classical flame retardants, related halogenated natural compounds and alternative flame retardants in three delphinids from Southern European waters.

    Science.gov (United States)

    Barón, E; Giménez, J; Verborgh, P; Gauffier, P; De Stephanis, R; Eljarrat, E; Barceló, D

    2015-08-01

    Occurrence and behaviour of classical (PBDEs) and alternative (HNs, HBB, PBEB, DBDPE and HBCD) flame retardants, together with naturally produced MeO-PBDEs, were studied in short-beaked common dolphin (Delphinus delphis), bottlenose dolphin (Tursiops truncatus) and long-finned pilot whale (Globicephala melas) in two sampling locations from Southern European waters. PBDEs, Dec 602, Dec 603, DP, α-HBCD and two MeO-PBDEs were detected in all three species. ∑PBDEs were between 17 and 2680 ng/g lw; ∑HNs were between 1.1 and 59 ng/g lw; α-HBCD levels ranged between 3.2 and 641 ng/g lw; ∑MeO-PBDEs were between 34 and 1966 ng/g lw. Bottlenose dolphins were the most contaminated species and some individuals could present health risk for endocrine disruption since levels found were above the reported threshold (1500 ng/g lw). Stable isotope analysis was used to evaluate the biomagnification capacity of these compounds. PBDEs, MeO-PBDEs and Dec 602 showed a significant positive correlation with trophic position. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Flame retardant tris(1,3-dichloro-2-propyl)phosphate (TDCPP) toxicity is attenuated by N-acetylcysteine in human kidney cells.

    OpenAIRE

    Killilea, DW; Chow, D; Xiao, SQ; Li, C; Stoller, ML

    2017-01-01

    Prolonged exposure to the flame retardants found in many household products and building materials is associated with adverse developmental, reproductive, and carcinogenic consequences. While these compounds have been studied in numerous epidemiological and animal models, less is known about the effects of flame retardant exposure on cell function. This study evaluated the toxicity of the commonly used fire retardant tris(1,3-dichloro-2-propyl)phosphate (TDCPP) in cell line derived from the k...

  10. A Novel Brominated Triazine-based Flame Retardant (TTBP-TAZ) in Plastic Consumer Products and Indoor Dust

    NARCIS (Netherlands)

    Ballesteros Gomez, A.M.; de Boer, J.; Leonards, P.E.G.

    2014-01-01

    The presence of a novel brominated flame retardant named 2,4,6-tris(2,4,6-tribromophenoxy)-1,3,5-triazine (TTBP-TAZ) is reported for the first time in plastic parts of consumer products and indoor dust samples. TTBP-TAZ was identified by untargeted screening and can be a replacement of the banned

  11. Current halogenated flame retardant concentrations in serum from residents of Shandong Province, China, and temporal changes in the concentrations.

    Science.gov (United States)

    Ma, Yulong; Li, Peng; Jin, Jun; Wang, Ying; Wang, Qinghua

    2017-05-01

    The residents of Shandong Province, China, are exposed to high concentrations of halogenated flame retardants because large amounts of halogenated flame retardants are produced in the province. We determined the concentrations of eight polybrominated diphenyl ether congeners (PBDEs), seven novel brominated flame retardants (NBFRs), and the two dechlorane plus isomers (DPs) in serum from residents of Shandong Province. The aim was to identify temporal trends in the concentrations of these pollutants. The mean total concentrations of PBDEs, NBFRs and DPs were 41, 2.2 and 2.1ng/g lipid in pooled serum samples collected in 2014, and were 32, 3.5 and 3.1ng/g lipid in pooled serum samples collected in 2015, respectively. Decabromodiphenyl ether was the dominant PBDE congener in all of the samples. The novel brominated flame retardant and dechlorane plus concentrations were between one and two orders of magnitude lower than the PBDE concentrations. The PBDE concentrations in serum decreased significantly between 2007 and 2015, but the pentabromobenzene, pentabromotoluene, and dechlorane plus concentrations were relatively stable. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Bis(2,2,2-trifluoroethyl) methylphosphonate: An Novel Flame-retardant Additive for Safe Lithium-ion Battery

    International Nuclear Information System (INIS)

    Zeng, Ziqi; Jiang, Xiaoyu; Wu, Binbing; Xiao, Lifen; Ai, Xinping; Yang, Hanxi; Cao, Yuliang

    2014-01-01

    Graphical abstract: - Highlights: • PFMP was synthesized as a flame-retardant additive. • The SET value of the electrolyte containing 20% TFMP shows the reduction of 86%. • The 20% TFMP electrolyte exhibits excellent electrochemical compatibility on the anode and cathode. - Abstract: A novel fluorinated alkyl phosphonate - bis(2,2,2-trifluoroethyl) methylphosphonate (TFMP) were synthesized as flame retardant to reduce the flammability of the electrolyte with minimal impact on the electrochemical performance of the electrode. The flammability and electrochemical properties of TFMP with various contents were evaluated using self-extinguishing time (SET), conductivity test, cyclic voltammetry (CV) and glavanostatic charge and discharge test. The experimental results demonstrated that the addition of 20 vol% TFMP can make the electrolyte be hardly flammable, exhibiting high-efficiency flame retardant. Moreover, the 20 vol% TFMP-containing electrolyte also exhibited insignificant influence on graphite anode with high initial capacity of 346 mAh g −1 and excellent capacity retention of 93% over 100 cycles. For LiFePO 4 cathode, the excellent electrochemical performance was observed including gradually increasing reversible capacity from 128 to 139 mAh g −1 over 100 cycles in the 20 vol% TFMP-containing electrolyte. The results imply that TFMP is a promising option as highly flame-retardant and electrochemically compatible electrolyte additive for safe lithium-ion batteries

  13. BROMINATION OF 4-VINYLCYCLOHEXANE AND APPLYING THE RESULTING PRODUCT TO IMPROVE THE FLAME RETARDANT PROPERTIES OF WOOD

    Directory of Open Access Journals (Sweden)

    N. S. Nikulina

    2014-01-01

    Full Text Available Currently, the demand for timber is increasing. Wood and products on its basis are considered to be the most popular in the construction industry, furniture industry, as building materials and other However, along with the positive features of this material there are also negative factors, which include low resistance to biological degradation, high temperature, resistance. Wood and materials based on it are the most flammable, and fire safety is characterized by the velocity of propagation of fire on the wooden structure. He is able to destroy it in a matter of minutes. So the wooden house elements must be protected from fire. It was therefore necessary for the fire protection of wood. It is in the handling of wood with flame retardants. Basic fire fighting methods is the impregnation of wood antipyrene composition, painting fire paint and constructive ways - insulation of timber, non-combustible compositions which can resist the fire. In the work of brominated 4-vinylcyclohexane formed as a by-product in the petrochemical industry, in chloroform synthesized compound with bromine 62-64 % and the possibility of using this product to get antiferromag composition. It is established that the application for the protective treatment of wood synthesized flame retardant has shown that this product can be used for the protective treatment of natural wood to make it flame retardant properties. Use as antiperiodic compositions bromodomain based products 4-vinylcyclohexane allows to obtain images of wood first group of flame retardant efficiency.

  14. Flame Retardancy Effects of Graphene Nanoplatelet/Carbon Nanotube Hybrid Membranes on Carbon Fiber Reinforced Epoxy Composites

    Directory of Open Access Journals (Sweden)

    Dongxian Zhuo

    2013-01-01

    Full Text Available Carbon nanotube/graphene nanoplatelet (MWCNT/GNP hybrid membranes with lower liquid permeability and better barrier effect compared to MWCNT membranes were successfully synthesized by vacuum filtering. Their morphologies, water permeability, and pore structures were characterized by a scanning electron microscope (SEM and nitrogen adsorption isotherms. Furthermore, MWCNT/GNP membranes were used to improve the flame retardancy of carbon fiber reinforced polymer (CFRP composites, and the influence of weight percentage of GNPs on the permeability and flame retardancy of MWCNT/GNP membranes was systematically investigated. Results show that incorporation of MWCNT/GNP membranes on CFRP composite plates can remarkably improve the flame retardancy of CFRP composites. Specifically, the incorporation of hierarchical MWCNT/GNP membrane with 7.5 wt% of GNP displays a 35% reduction in the peak heat release rate (PHRR for a CFRP composite plate with the epoxy as matrix and a 11% reduction in PHRR compared with the incorporation of MWCNT membrane only. A synergistic flame retarding mechanism is suggested to be attributed to these results, which includes controlling the pore size and penetrative network structure.

  15. Facile Fabrication of a PDMS@Stearic Acid-Kaolin Coating on Lignocellulose Composites with Superhydrophobicity and Flame Retardancy

    Directory of Open Access Journals (Sweden)

    Zhe Wang

    2018-05-01

    Full Text Available The disadvantages such as swelling after absorbing water and flammability restrict the widespread applications of lignocellulose composites (LC. Herein, a facile and effective method to fabricate superhydrophobic surfaces with flame retardancy on LC has been investigated by coating polydimethylsiloxane (PDMS and stearic acid (STA modified kaolin (KL particles. The as-prepared coatings on the LC exhibited a good repellency to water (a contact angle = 156°. Owing to the excellent flame retardancy of kaolin particles, the LC coated with PDMS@STA-KL displayed a good flame retardancy during limiting oxygen index and cone calorimeter tests. After the coating treatment, the limiting oxygen index value of the LC increased to 41.0. Cone calorimetry results indicated that the ignition time of the LC coated with PDMS@STA-KL increased by 40 s compared with that of uncoated LC. Moreover, the peak heat release rate (PHRR and the total heat release (THR of LC coated with PDMS@STA-KL reduced by 18.7% and 19.2% compared with those of uncoated LC, respectively. This LC coating with improved water repellency and flame retardancy can be considered as a potential alternative to protect the lignocellulose composite.

  16. Transcriptional and Epigenetic Mechanisms Underlying Enhanced in Vitro Adipocyte Differentiation by the Brominated Flame Retardant BDE-47

    NARCIS (Netherlands)

    Kamstra, J.H.; Hruba, E.; Blumberg, B.; Janesick, A.; Mandrup, S.; Hamers, T.; Legler, J.

    2014-01-01

    Recent studies suggest that exposure to endocrine-disrupting compounds (EDCs) may play a role in the development of obesity. EDCs such as the flame retardant 2,2′,4,4′-tetrabrominated diphenyl ether (BDE-47) have been shown to enhance adipocyte differentiation in the murine 3T3-L1 model the

  17. Accumulation of organochlorines and brominated flame retardants in estuarine and marine food chains : Field measurements and model calculations

    NARCIS (Netherlands)

    Veltman, Karin; Hendriks, Jan; Huijbregts, Mark; Leonards, Pim; Van Den Heuvel-Greve, Martine; Vethaak, Dick

    2005-01-01

    Food chain accumulation of organochlorines and brominated flame retardants in estuarine and marine environments is compared to model estimations and fresh water field data. The food chain consists of herbivores, detritivores and primary and secondary carnivores i.e. fish, fish-eating birds and

  18. Accumulation of organochlorines and brominated flame retardants in estuarine and marine food chains: Field measurements and model calculations

    NARCIS (Netherlands)

    Veltman, K.; Hendriks, J.; Huijbregts, M.; Leonards, P.E.G.; Heuvel-Greve, van den M.J.; Vethaak, D.

    2005-01-01

    Food chain accumulation of organochlorines and brominated flame retardants in estuarine and marine environments is compared to model estimations and fresh water field data. The food chain consists of herbivores, detritivores and primary and secondary carnivores i.e. fish, fish-eating birds and

  19. Emerging and historical halogenated flame retardants in fish samples from Iberian rivers.

    Science.gov (United States)

    Santín, G; Barón, E; Eljarrat, E; Barceló, D

    2013-12-15

    Forty-eight fish samples from the Llobregat, Ebro, Júcar and Guadalquivir river basins (Spain), were analyzed for polybrominated diphenyl ethers (PBDEs), decabromodiphenyl ethane (DBDPE), hexabromobenzene (HBB), pentabromoethylbenzene (PBEB) and halogenated norbornenes (HNs). The most contaminated river basin was the Llobregat, followed by the Ebro, Júcar and Guadalquivir for almost every analyzed contaminant. Most abundant PBDE congener was BDE-47 (BDL-396 ng/g lw) and the most abundant halogenated norbornene was Dechlorane-602 (BQL-174 ng/g lw). Fanti was calculated to determine the different bioaccumulation/biodegradation of syn-DP and anti-DP. Biota to sediment accumulation factor was calculated in order to compare the bioaccumulation capacity of emerging flame retardants with that of "classical" PBDEs. It was found that bioaccumulation of halogenated norbornenes is lower than that of PBDEs. BDE-99, HBB, PBEB and Dechlorane-604 were not detected in any sample. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Brominated flame retardants (BFRs) in eggs from birds of prey from Southern Germany, 2014.

    Science.gov (United States)

    Vetter, Walter; Gallistl, Christoph; Schlienz, Annika; Preston, Theresa; Müller, Jens; von der Trenck, K Theo

    2017-12-01

    In Southern Germany, peregrine falcons (Falco peregrinus), which almost exclusively prey on other birds, are top predators of the terrestrial food chain. These animals accumulate persistent organic pollutants (POPs) and halogenated flame retardants (HFRs) with mothers transferring these lipophilic contaminants to their eggs. Here we analyzed unhatched eggs of eleven peregrine falcons and six of other species, and report concentrations of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), hexabromobenzene (HBB), 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) and its metabolites, pentabromoethylbenzene (PBEB), pentabromotoluene (PBT), and tribromophenol (TBP). The extract of one purified peregrine falcon egg sample was comprehensively analyzed in a non-target (NT) approach by gas chromatography with mass spectrometry in the electron capture negative ion mode. A total of ∼400 polyhalogenated compounds were detected, among them dechloranes and possibly transformation products, two tetrabrominated metabolites of PBT and several compounds unknown to us which could not be identified. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Particle size distribution of brominated flame retardants in house dust from Japan

    Directory of Open Access Journals (Sweden)

    Natsuko Kajiwara

    2016-06-01

    Full Text Available The present study was conducted to examine the concentrations, profiles, and mass distributions of polybrominated diphenyl ethers (PBDEs, hexabromocyclododecanes (HBCDs, and polybrominated dibenzo-p-dioxins/furans (PBDD/Fs based on the particle sizes of house dust samples from five homes in Japan. After removal of impurities from house dust from vacuum cleaner bags, selected indoor dust samples were size fractionated (>2 mm, 1–2 mm, 0.5–1 mm, 250–500 μm, 106–250 μm, 53–106 μm, and 250 μm in size and fluffy dust were included. The conclusion is that particulate dust <250 μm in size without fluffy dust should be used to analyze dust for brominated flame retardants.

  2. Effect of structural parameters on burning behavior of polyester fabrics having flame retardancy property

    Science.gov (United States)

    Çeven, E. K.; Günaydın, G. K.

    2017-10-01

    The aim of this study is filling the gap in the literature about investigating the effect of yarn and fabric structural parameters on burning behavior of polyester fabrics. According to the experimental design three different fabric types, three different weft densities and two different weave types were selected and a total of eighteen different polyester drapery fabrics were produced. All statistical procedures were conducted using the SPSS Statistical software package. The results of the Analysis of Variance (ANOVA) tests indicated that; there were statistically significant (5% significance level) differences between the mass loss ratios (%) in weft and mass loss ratios (%) in warp direction of different fabrics calculated after the flammability test. The Student-Newman-Keuls (SNK) results for mass loss ratios (%) both in weft and warp directions revealed that the mass loss ratios (%) of fabrics containing Trevira CS type polyester were lower than the mass loss ratios of polyester fabrics subjected to washing treatment and flame retardancy treatment.

  3. Separation of Flame and Nonflame-retardant Plastics Utilizing Magneto-Archimedes Method

    Science.gov (United States)

    Misawa, Kohei; Kobayashi, Takayuki; Mori, Tatsuya; Mishima, Fumihito; Akiyama, Yoko; Nishijima, Shigehiro

    2017-07-01

    In physical recycling process, the quality of recycled plastics becomes usually poor in case various kinds of plastic materials are mixed. In order to solve the problem, we tried to separate flame and nonflame-retardant plastics used for toner cartridges as one example of mixed plastics by using magneto-Archimedes method. By using this method, we can control levitation and settlement of the particles in the medium by controlling the density and magnetic susceptibility of the medium and the magnetic field. In this study, we introduced the separation system of plastics by the combination of wet type specific gravity separation and magneto-Archimedes separation. In addition, we examined continuous and massive separation by introducing the system which can separate the plastics continuously in the flowing fluid.

  4. Advances in Instrumental Analysis of Brominated Flame Retardants: Current Status and Future Perspectives

    Science.gov (United States)

    2014-01-01

    This review aims to highlight the recent advances and methodological improvements in instrumental techniques applied for the analysis of different brominated flame retardants (BFRs). The literature search strategy was based on the recent analytical reviews published on BFRs. The main selection criteria involved the successful development and application of analytical methods for determination of the target compounds in various environmental matrices. Different factors affecting chromatographic separation and mass spectrometric detection of brominated analytes were evaluated and discussed. Techniques using advanced instrumentation to achieve outstanding results in quantification of different BFRs and their metabolites/degradation products were highlighted. Finally, research gaps in the field of BFR analysis were identified and recommendations for future research were proposed. PMID:27433482

  5. Analytical developments and preliminary assessment of human exposure to organophosphate flame retardants from indoor dust.

    Science.gov (United States)

    Van den Eede, Nele; Dirtu, Alin C; Neels, Hugo; Covaci, Adrian

    2011-02-01

    A new and efficient analytical method was developed and validated for the analysis of organophosphorus flame retardants (OPFRs) in indoor dust samples. This method involves an extraction step by ultrasonication and vortex, followed by extract clean-up with Florisil solid-phase extraction cartridges and analysis of the purified extracts by gas chromatography-mass spectrometry (GC-MS). Method recoveries ranged between 76 and 127%, except for volatile OPFRs, such as triethyl phosphate (TEP) and tri-(n-propyl) phosphate (TnPP), which were partially lost during evaporation steps. The between day precision on spiked dust samples was TDCPP) was increased by a factor >5. Copyright © 2010 Elsevier Ltd. All rights reserved.

  6. Levels and distributions of organophosphate flame retardants and plasticizers in sediment from Taihu Lake, China.

    Science.gov (United States)

    Cao, Shuxia; Zeng, Xiangying; Song, Han; Li, Huiru; Yu, Zhiqiang; Sheng, Guoying; Fu, Jiamo

    2012-07-01

    The concentrations and distribution of seven organophosphate flame retardants and plasticizers (OPs) were investigated in 28 sediment samples collected from Taihu Lake. The analytes were ultrasonically extracted, enriched using solid-phase extraction, and determined by gas chromatography-mass spectrometry. The results indicated that the analytes were all detected in the sediments. The total concentrations of seven OPs ranged from 3.38 to 14.25 µg/kg, and tris (2-chloroiso-propyl) phosphate (TCPP), tris (2-chloroethyl) phosphate (TCEP), and tris (2-butoxyethyl) phosphate (TBEP) were the dominant compounds, with concentrations ranging fromTDCPP) as the main component at the sampling site. This result implied that there is an obvious emission source nearby at Suzhou City; in addition, human activities also play an important role in the concentration of OPs in the sediment. Copyright © 2012 SETAC.

  7. Eco-friendly finishing agent for cotton fabrics to improve flame retardant and antibacterial properties.

    Science.gov (United States)

    El-Shafei, A; ElShemy, M; Abou-Okeil, A

    2015-03-15

    This research work deals with flame retardant and antibacterial finishing agent for cellulosic fabrics using TiO2 nanoparticles and chitosan phosphate. TiO2 nanoparticles were prepared by sol-gel method using titanium tetraisopropoxide. The size of TiO2 nanoparticles was characterized using transmission electron microscope (TEM). The application of nano TiO2 onto cellulosic fabrics (cotton 100%) was achieved in presence of polycarboxylic acid [1,2,3,4-butane tetracarboxylic acid (BTCA)] with sodium hypophosphite (SHP) as catalyst and chitosan phosphate through conventional pad-dry-cure method. The effect of the finishing on the physical properties, flammability and antibacterial properties of cross-linked fabrics are investigated. Thermal gravimetric analysis (TGA) was employed to investigate the thermal decomposition behaviour of the treated samples. Limited oxygen indexes (LOI) of the treated cotton fabrics were investigated. The treated cotton fabric also reveals excellent antibacterial properties. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Does exposure to flame retardants increase the risk for preterm birth?

    Science.gov (United States)

    Peltier, Morgan R; Koo, Hschi-Chi; Getahun, Darios; Menon, Ramkumar

    2015-02-01

    During the past 40 years, polybrominated diphenyl ethers (PBDEs) have been widely used as flame retardants and nearly all women have some level of exposure. PBDEs have been isolated from amniotic fluid and cord plasma indicating vertical transmission; however, their effects on pregnancy outcome are largely unknown. Therefore, we quantified PBDE-47, the most common congener in maternal plasma samples collected at the time of labor from women who subsequently had term or preterm birth (PTB). Women were then scored based on whether or not they had very low, low, medium, high or very high peripheral plasma concentrations of PBDE-47. Probit regression analysis suggested that women in the PTB group had a greater chance of scoring higher on this scale (Pmaternal exposure to PBDEs might increase the risk for PTB. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  9. Characterization of brominated flame retardants from e-waste components in China.

    Science.gov (United States)

    Yu, Danfeng; Duan, Huabo; Song, Qingbin; Liu, Yicheng; Li, Ying; Li, Jinhui; Shen, Weijun; Luo, Jiahui; Wang, Jinben

    2017-10-01

    Many studies show that high levels of many toxic metals and persistent and bio-accumulative chemicals have been found in electronic waste (e-waste) dismantling sites and their surrounding environmental media. Both flame-retardant plastic housing materials and printed circuit boards (PCBs) could be the major contributors. However, relatively little work has focused on the use or content of toxic substances and their changing in scrap housing materials and PCBs from home appliances. This study evaluated the existence of brominated flame retardants (BFRs, including polybrominated diphenyl ethers (PBDEs) and Tetrabromobisphenol-A (TBBPA)) in housing plastics and PCBs from home appliances collected from various e-waste recyclers in China. These were then analyzed for the potential migration of BFRs from the e-waste components into their recycled products. The results show that both PBDEs and TBBPA were found with high level in most of e-waste samples, indicating that the widespread use of BFRs in home appliances are entering into the end-of-life stage. For the plastics samples, CRT TVs and LCD monitors should be given priority for the control of BFRs. Regarding PBDEs, the dominant congeners of BDE-209 in the plastics samples contributed 90.72-93.54% to the total concentrations of PBDEs, yet there are large variations for PCBs samples: BDE-28, -47, -99, and -153 were also important congeners compositions, except for BDE-209. Compared with previous studies, the BFRs concentrations in current Chinese e-waste are trending to decline. This study also found that BFRs in housing plastics and PCBs will be transferred into the recycled products with other purpose use, and the new products could have highly enriched capacities for BFRs. The obtained results could be helpful to manage e-waste and their components properly in order to minimize associated environmental and health risks of BFRs, particularly for their further reuse. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Synthesis and carbonization chemistry of a phosphorous-nitrogen based intumescent flame retardant

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Haiyun, E-mail: mahaiyun@gmail.com [College of Chemistry and Environmental Science, HeBei University, Baoding, Hebei Province 071002 (China); Fang, Zhengping [MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Institute of Polymer Composites, Zhejiang University, Hangzhou 310027 (China); Laboratory of Polymer Materials and Engineering, Ningbo Institute of Technology, Zhejiang University, Ningbo 315100 (China)

    2012-09-10

    Graphical abstract: The carbonization chemistry and mechanism of a novel synthesized intumescent flame retardant. The final chars showed a complex P-O-Ph and aromatic/graphitic structure containing architecture. Highlights: Black-Right-Pointing-Pointer The IFR synthesized is polymeric and has high molecular weight. Black-Right-Pointing-Pointer The IFR has a higher thermal stability than most of the commercial IFRs. Black-Right-Pointing-Pointer The final chars of IFR showed a complex P-O-Ph and aromatic/graphitic structure. - Abstract: In this work, a polymeric phosphorous-nitrogen containing intumescent flame retardant, named poly(diaminodiphenyl methane spirocyclic pentaerythritol bisphosphonate) (PDSPB), was synthesized. The carbonization chemistry was investigated. FTIR and {sup 1}H NMR were used to confirm the chemical structure of PDSPB. Thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), in situ FTIR and energy dispersive X-ray (EDX) were used to investigate and monitor the chemical structural changes during thermal degradation. PDSPB demonstrated a three-step degradation behavior. PDSPB oligomers continuously polymerized and generated a higher macromolecular weight during the first step (200-250 Degree-Sign C). The phosphate ester bonds were broken down and phosphoric acid was released which dehydrated the carbon source to form chars during the second step (280-320 Degree-Sign C). The residues will be further degraded and form final chars during the final weight loss step (400-450 Degree-Sign C). The final chars showed a complex P-O-Ph and aromatic/graphitic structure containing architecture.

  11. Detection of novel brominated flame retardants (NBFRs in the urban soils of Melbourne, Australia

    Directory of Open Access Journals (Sweden)

    Thomas J. McGrath

    2017-03-01

    Full Text Available A range of brominated flame retardants (BFRs have been incorporated into polymeric materials like plastics, electronic equipment, foams and textiles to prevent fires. The most common of these, polybrominated diphenyl ethers (PBDEs, have been subject to legislated bans and voluntary withdrawal by manufacturers in North America, Europe and Australia over the past decade due to long-range atmospheric transport, persistence in the environment, and toxicity. Evidence has shown that replacement novel brominated flame retardants (NBFRs are released to the environment by the same mechanisms as PBDEs and share similar hazardous properties. The objective of the current research was to characterize soil contamination by NBFRs in the urban soils of Melbourne, Australia. A variety of industrial and non-industrial land-uses were investigated with the secondary objective of determining likely point sources of pollution. Six NBFRs; pentabromotoluene (PBT, pentabromoethylbenzene (PBEB, hexabromobenzene (HBB, 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB, 1,2-bis(2,4,6-tribromophenoxyethane (BTBPE and decabromodiphenyl ethane (DBDPE were measured in 30 soil samples using selective pressurized liquid extraction (S-PLE and gas chromatography coupled to triple quadrupole mass spectrometry (GC-MS/MS. NBFRs were detected in 24/30 soil samples with Σ5NBFR concentrations ranging from nd-385 ng/g dw. HBB was the most frequently detected compound (14/30, while the highest concentrations were observed for DBDPE, followed by BTBPE. Electronic waste recycling and polymer manufacturing appear to be key contributors to NBFR soil contamination in the city of Melbourne. A significant positive correlation between Σ8PBDEs and Σ5NBFR soil concentrations was observed at waste disposal sites to suggest that both BFR classes are present in Melbourne's waste streams, while no association was determined among manufacturing sites. This research provides the first account of NBFRs

  12. Demographic and dietary risk factors in relation to urinary metabolites of organophosphate flame retardants in toddlers.

    Science.gov (United States)

    Thomas, M B; Stapleton, H M; Dills, R L; Violette, H D; Christakis, D A; Sathyanarayana, S

    2017-10-01

    Organophosphate flame retardants (OPFRs), including Tris (1,3-dichloro-isopropyl) phosphate (TDCPP), triphenyl phosphate (TPP), and isopropylated triphenyl phosphate (ITP), are increasingly used in consumer products because of the recent phase out of polybrominated diphenyl ether (PBDE) flame retardants. OPFRs have been widely detected in adults and have been linked to reproductive and endocrine changes in adult males. Carcinogenicity and damage to immunologic, neurologic and developmental systems have been observed in human cell lines. Young children are especially vulnerable to OPFR exposure, but little is known about exposure levels or exposure risk factors in this population. We examined parent-reported demographic and dietary survey data in relation to OPFR urinary metabolite concentrations in 15- to 18-month old toddlers (n = 41). OPFR metabolites were detected in 100% of subjects. The metabolite of TPP, diphenyl phosphate (DPP) was detected most commonly (100%), with TDCPP metabolite, bis(1,3-dichloro-2-propyl) phosphate (BDCPP), detected in 85-95% of samples, and ITP metabolite, monoisopropylphenyl phenyl phosphate (ip-DPP), detected in 81% of samples (n = 21). Toddlers of mothers earning $10,000/year (7.8 ng/mL, 95% CI 5.03, 12.11 and 4.69 ng/mL, 95% CI 3.65-6.04, respectively). While no dietary factors were significantly associated with OPFR metabolite concentrations, results suggested meat and fish consumption may be associated with higher DPP and BDCPP levels while increased dairy and fresh food consumption may be associated with lower DPP, BDCPP, and ip-DPP levels. Research with larger sample sizes and more detailed dietary data is required to confirm these preliminary findings. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Distribution of copper, silver and gold during thermal treatment with brominated flame retardants

    International Nuclear Information System (INIS)

    Oleszek, Sylwia; Grabda, Mariusz; Shibata, Etsuro; Nakamura, Takashi

    2013-01-01

    Highlights: • Copper, silver and gold during thermal treatment with brominated flame retardants. • Distribution of copper, silver and gold during thermal processing. • Thermodynamic considerations of the bromination reactions. - Abstract: The growing consumption of electric and electronic equipment results in creating an increasing amount of electronic waste. The most economically and environmentally advantageous methods for the treatment and recycling of waste electric and electronic equipment (WEEE) are the thermal techniques such as direct combustion, co-combustion with plastic wastes, pyrolysis and gasification. Nowadays, this kind of waste is mainly thermally treated in incinerators (e.g. rotary kilns) to decompose the plastics present, and to concentrate metals in bottom ash. The concentrated metals (e.g. copper, precious metals) can be supplied as a secondary raw material to metal smelters, while the pyrolysis of plastics allows the recovery of fuel gases, volatilising agents and, eventually, energy. Indeed, WEEE, such as a printed circuit boards (PCBs) usually contains brominated flame retardants (BFRs). From these materials, hydrobromic acid (HBr) is formed as a product of their thermal decomposition. In the present work, the bromination was studied of copper, silver and gold by HBr, originating from BFRs, such as Tetrabromobisphenol A (TBBPA) and Tetrabromobisphenol A-Tetrabromobisophenol A diglycidyl ether (TTDE) polymer; possible volatilization of the bromides formed was monitored using a thermo-gravimetric analyzer (TGA) and a laboratory-scale furnace for treating samples of metals and BFRs under an inert atmosphere and at a wide range of temperatures. The results obtained indicate that up to about 50% of copper and silver can evolve from sample residues in the form of volatile CuBr and AgBr above 600 and 1000 °C, respectively. The reactions occur in the molten resin phase simultaneously with the decomposition of the brominated resin. Gold is

  14. Bioaccumulation and biomagnification of classical flame retardants, related halogenated natural compounds and alternative flame retardants in three delphinids from Southern European waters

    International Nuclear Information System (INIS)

    Barón, E.; Giménez, J.; Verborgh, P.; Gauffier, P.; De Stephanis, R.; Eljarrat, E.; 2O Building, Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona (Spain))" data-affiliation=" (Institute of Environmental Assessment and Water Research Studies (IDAEA), Spanish Council for Scientific Research (CSIC), Jordi Girona 18-26, 08034 Barcelona (Spain); Catalan Institute for Water Research (ICRA), H2O Building, Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona (Spain))" >Barceló, D.

    2015-01-01

    Occurrence and behaviour of classical (PBDEs) and alternative (HNs, HBB, PBEB, DBDPE and HBCD) flame retardants, together with naturally produced MeO-PBDEs, were studied in short-beaked common dolphin (Delphinus delphis), bottlenose dolphin (Tursiops truncatus) and long-finned pilot whale (Globicephala melas) in two sampling locations from Southern European waters. PBDEs, Dec 602, Dec 603, DP, α-HBCD and two MeO-PBDEs were detected in all three species. ∑PBDEs were between 17 and 2680 ng/g lw; ∑HNs were between 1.1 and 59 ng/g lw; α-HBCD levels ranged between 3.2 and 641 ng/g lw; ∑MeO-PBDEs were between 34 and 1966 ng/g lw. Bottlenose dolphins were the most contaminated species and some individuals could present health risk for endocrine disruption since levels found were above the reported threshold (1500 ng/g lw). Stable isotope analysis was used to evaluate the biomagnification capacity of these compounds. PBDEs, MeO-PBDEs and Dec 602 showed a significant positive correlation with trophic position. - Highlights: • Several FRs were detected in three dolphin species from Southern European waters. • Concentrations of classical FRs were higher than concentrations of alternative FRs. • MeO-PBDE concentrations were generally similar to PBDE concentrations. • Evidence of biomagnification capacity of some FRs was observed. • Some individuals were above the threshold level associated to endocrine disruption. - Bioaccumulation and biomagnification of halogenated compounds in dolphins

  15. Development of flame retardant PV module encapsulants: Volume 1. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Galica, J.P.

    1998-06-01

    This Phase 1 final report covers the work performed by Springborn Testing and Research, Inc., for the period October 1, 1997 to June 30, 1998 under the Department of Energy Cooperative Agreement Number DE-FC36-97GO10255, entitled Development of Flame Retardant PV Module Encapsulants. While use of roof-mounted arrays has always been an attractive means of deploying PV, only within recent years have such building integrated concepts (BIPV) found renewed interest among module makers and end-users. Prior to building integrated and rooftop applications, flammability requirements for modules have not been a great industry concern. However, with growing interest in BIPV and the requirement for building code requirements for commercial and industrial structures, flammability issues have become a barrier to entry for many module constructions into this potentially huge domestic market for PV. The overall goal of the 3 phase PV BONUS two project is to develop and commercialize a line of fire retardant encapsulation materials to serve the emerging building integrated and building mounted PV market. The objectives of the Phase 1 effort are limited to concept development and business planning activities.

  16. The Effects of Difunctional Urone Catalysis on Selected Non-Halogenated Flame Retardant Synergies of Dicyandiamide Cured Epoxy Resins

    Science.gov (United States)

    Phillips, Nathan M.

    A standard grade diglycidyl ether of bisphenol-A, DGEBA, epoxy resin was evaluated using differential scanning calorimetry, DSC, to determine the optimum stoichiometric balance of a dicyandiamide, DICY, curing agent. The maximum attainable glass transition temperature, Tg, was used as a reference point for the optimal reactivity. The stoichiometric value was found to be 8 epoxy groups to 1 equivalent of dicyandiamide, or an 80% stoichiometric ratio. This value lies within the known literature range of 7-8.5 epoxy groups per dicyandiamide molecule. The optimal blend was then catalyzed with 1, 2 and 3 parts by weight, PBW, of Dyhard UR500, a difunctional urone catalyst. A separate blend was developed for each addition level of Dyhard UR500. Six non-halogenated flame retardants synergies were selected from the literature, and each flame retardant was incorporated at 10 PBW into a separate optimized DGEBA/DICY blend, which contained either 0,1,2 or 3 PBW Dyhard UR500. Cured neat resin and composite samples for each synergy, with each addition level of catalyst, were evaluated to determine the effects of urone catalysis on known non-halogenated flame retardant synergies. The neat resin analysis was performed using thermogravimetric analysis, TGA. The ASTM methods of E1641 and E1877 were used to determine the slope of the thermal endurance graph, or RTI, the slope of the relative thermal index. Composite laminates were prepared using T300B 3K carbon fiber containing 40% resin content, and five samples were evaluated in accordance with the UL-94 test standard. The DSC data showed a reduction in Tg with each increased PBW of urone catalyst. The observed reduction in Tg for these blends is understood to be an accurate representation for the decrease in crosslink density resulting from chain termination during cure. A comparison between the slope of RTI and the UL-94 test data indicate that this reduction in crosslink density has different influences on the flammability and

  17. Product screening for sources of halogenated flame retardants in Canadian house and office dust

    International Nuclear Information System (INIS)

    Abbasi, Golnoush; Saini, Amandeep; Goosey, Emma; Diamond, Miriam L.

    2016-01-01

    Human exposure to halogenated flame retardants (HFRs) such as polybrominated diphenyl ethers (PBDEs) and their replacements, can be related to exposure to indoor dust and direct contact with HFR-containing products. This study aimed to identify electronic products that contributed to HFRs measured in indoor dust and to develop a screening method for identifying HFRs in hard polymer products. Concentrations of 10 PBDEs and 12 halogenated replacements in dust and surface wipe samples of hard polymer casings of electronic products plus Br in the surfaces of those casing measured using X-ray fluorescence (XRF) were analyzed from 35 homes and 10 offices in Toronto (ON, Canada). HFR concentrations in dust and product wipes were positively correlated. Thus, we hypothesize that electronic products with the highest HFR concentrations contribute the most to concentrations in dust, regardless of the volatility of the HFR. Abundant HFRs in dust and product wipes were PBDEs (BDE-47, 99, 100, 153, 154, 183, 209), TDCPP, DBDPE, EH-TBB and BEHTBP. Older CRT TVs had the highest concentration of BDE-209 of all products tested. This was followed by higher concentrations of HFRs in PCs, Audio/Video (A/V) devices, small household appliances (HHAs) and flat screen TVs. The removal of HFRs from polymer surfaces using wipes supports concerns that HFRs could be transferred from these surfaces to hands as a result of direct contact with HFR-containing products. Surface wipe testing shows promise for screening additive HFRs. In comparison, the Br-content obtained using a handheld XRF analyzer did not correspond to concentrations obtained from surface wipe testing. - Highlights: • Concentrations of flame retardants in dust correlated with product surface wipes • Most abundant FRs in electronics were PBDEs, TDCPP, DBDPE, EH-TBB and BEHTBP. • Descending order of FRs in CRTs, TVs, PCs, A-V devices, and small household appliances • Product wipe testing, but not XRF, useful for non

  18. Product screening for sources of halogenated flame retardants in Canadian house and office dust

    Energy Technology Data Exchange (ETDEWEB)

    Abbasi, Golnoush [Department of Geography, University of Toronto, 100 St. George St., Toronto M5S 3G3 (Canada); Saini, Amandeep [Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail, Toronto M1C 1A4 (Canada); Goosey, Emma [Department of Earth Sciences, University of Toronto, 22 Russell Street, Toronto M5S 3B1 (Canada); Diamond, Miriam L., E-mail: miriam.diamond@utoronto.ca [Department of Earth Sciences, University of Toronto, 22 Russell Street, Toronto M5S 3B1 (Canada); Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail, Toronto M1C 1A4 (Canada)

    2016-03-01

    Human exposure to halogenated flame retardants (HFRs) such as polybrominated diphenyl ethers (PBDEs) and their replacements, can be related to exposure to indoor dust and direct contact with HFR-containing products. This study aimed to identify electronic products that contributed to HFRs measured in indoor dust and to develop a screening method for identifying HFRs in hard polymer products. Concentrations of 10 PBDEs and 12 halogenated replacements in dust and surface wipe samples of hard polymer casings of electronic products plus Br in the surfaces of those casing measured using X-ray fluorescence (XRF) were analyzed from 35 homes and 10 offices in Toronto (ON, Canada). HFR concentrations in dust and product wipes were positively correlated. Thus, we hypothesize that electronic products with the highest HFR concentrations contribute the most to concentrations in dust, regardless of the volatility of the HFR. Abundant HFRs in dust and product wipes were PBDEs (BDE-47, 99, 100, 153, 154, 183, 209), TDCPP, DBDPE, EH-TBB and BEHTBP. Older CRT TVs had the highest concentration of BDE-209 of all products tested. This was followed by higher concentrations of HFRs in PCs, Audio/Video (A/V) devices, small household appliances (HHAs) and flat screen TVs. The removal of HFRs from polymer surfaces using wipes supports concerns that HFRs could be transferred from these surfaces to hands as a result of direct contact with HFR-containing products. Surface wipe testing shows promise for screening additive HFRs. In comparison, the Br-content obtained using a handheld XRF analyzer did not correspond to concentrations obtained from surface wipe testing. - Highlights: • Concentrations of flame retardants in dust correlated with product surface wipes • Most abundant FRs in electronics were PBDEs, TDCPP, DBDPE, EH-TBB and BEHTBP. • Descending order of FRs in CRTs, TVs, PCs, A-V devices, and small household appliances • Product wipe testing, but not XRF, useful for non

  19. Hierarchical Polyphosphazene@Molybdenum Disulfide Hybrid Structure for Enhancing the Flame Retardancy and Mechanical Property of Epoxy Resins.

    Science.gov (United States)

    Zhou, Xia; Qiu, Shuilai; Xing, Weiyi; Gangireddy, Chandra Sekhar Reddy; Gui, Zhou; Hu, Yuan

    2017-08-30

    A novel polyphosphazene (PZS) microsphere@molybdenum disulfide nanoflower (MoS 2 ) hierarchical hybrid architecture was first synthesized and applied for enhancing the mechanical performance and flame retardancy of epoxy (EP) resin via a cooperative effect. Herein, using PZS microsphere as the template, a layer of MoS 2 nanoflowers were anchored to PZS spheres via a hydrothermal strategy. The well-designed PZS@MoS 2 exhibits excellent fire retardancy and a reinforcing effect. The obtained PZS@MoS 2 significantly enhanced the flame-retardant performance of EP composites, which can be proved by thermogravimetric and cone calorimeter results. For instance, the incorporation of 3 wt % PZS@MoS 2 brought about a 41.3% maximum reduction in the peak heat-release rate and decreased by 30.3% maximum in the total heat release, accompanying the higher graphitized char layer. With regard to mechanical property, the storage modulus of EP/PZS@MoS 2 3.0 in the glassy state was dramatically increased to 22.4 GPa in comparison with that of pure EP (11.15 GPa). It is sensible to know that the improved flame-retardant performance for EP composites is primarily assigned to a physical barrier effect of the MoS 2 nanoflowers and the polyphosphazene structure has an positive impact on promoting char formation in the condensed phase.

  20. Preparation of flame-retardant polyethylene terephthalate fabrics by electron beam-induced grafting of oligomeric vinyl phosphonate

    International Nuclear Information System (INIS)

    Kaji, Kanako; Ohkura, Hiroshi; Okada, Toshio.

    1979-01-01

    For the purpose of making polyethylene terephthalate (polyester) fabric, flame-retardant grafting of oligomeric vinyl phosphonate was carried out using electron-beams either from a Van de Graaff or a Transformer-Rectifier type accelerator at a dose rate of up to 3.3 x 10 6 rad/sec. The fabric impregnated with a selected amount of oligomer was irradiated for the grafting. In the present report ''grafting'' means only an apparent one and it is very probable that most of the oligomer is deposited on the surface of the fibers as insoluble polymer due to cross-linking. When 20% methanol solution of the oligomer was used, an average amount of oligomer take up was about 25% and an add-on by grafting up to 20% was obtained at a dose of 20 Mrad with oligomer utilization higher than 75%. Flame retardance of the fabric is much improved by the grafting. Limiting oxygen index (LOI) increases from 18.5 of original fabric to 26.0 of the fabric containing 12% phosphorus. The fabric of 10% add-on (phosphorus content 2.2%) was proved to be self-extinguishing when it was exposed to open flame according to a netting basket flame-retardance test. The flame-retardance is obtained at LOI of 23.0. The graft fabric exhibited much improved anti-static property. At about 3% add-on the frictional electric charge was lowered to the same level as that cotton fabric. Thermal stability of the graft fabric tested by thermogravimetric analysis shows that it is far better than the chlorinated fabrics. No or a very little change in tensile properties of the fabric was observed upon grafting oligomeric vinyl phosphonate. The graft fabric has an excellent hand. (author)

  1. A new strategy to produce low-density polyethylene (LDPE)-based composites simultaneously with high flame retardancy and high mechanical properties

    Science.gov (United States)

    Shen, Liguo; Li, Jianxi; Li, Renjie; Lin, Hongjun; Chen, Jianrong; Liao, Bao-Qiang

    2018-04-01

    In this study, a new strategy which blends low-density polyethylene (LDPE), magnesium hydroxide (MH) and lauryl acrylate by electron-beam radiation for production of LDPE-based composites with high performance was proposed. It was found that, MH played main roles in flame retardancy but reduced processing flow and mechanical properties of the composites. Meanwhile, melt flow rate (MFR) increased while viscosity of the composites decreased with lauryl acrylate content increased, facilitating LDPE composites processing. Electron beam radiation could prompt crosslinking of lauryl acrylate, which significantly enhanced the mechanical properties of LDPE composites. Meanwhile, lauryl acrylate addition only slightly decreased the flame retardancy, suggesting that LDPE composites could remain high flame retardancy even when lauryl acrylate content was high. The study highly demonstrated the feasibility to produce LDPE-based composites simultaneously with high flame retardancy and high mechanical properties by the blending strategy provided in this study.

  2. Comprehensive Environmental Assessment Applied to Multiwalled Carbon Nanotube Flame-Retardant Coatings in Upholstery Textiles: A Case Study Presenting Priority Research Gaps for Future Risk Assessments (Final Report)

    Science.gov (United States)

    In September 2013, EPA announced the availability of the final report, Comprehensive Environmental Assessment Applied to Multiwalled Carbon Nanotube Flame-Retardant Coatings in Upholstery Textiles: A Case Study Presenting Priority Research Gaps for Future Risk Assessments...

  3. Brominated flame retardants in black plastic kitchen utensils: Concentrations and human exposure implications.

    Science.gov (United States)

    Kuang, Jiangmeng; Abdallah, Mohamed Abou-Elwafa; Harrad, Stuart

    2018-01-01

    Concerns exist that restricted brominated flame retardants (BFRs) present in waste polymers may have, as a result of recycling, inadvertently contaminated items not required to meet flame retardancy regulations (e.g. plastic kitchen utensils). To investigate the extent to which kitchen utensils are contaminated with BFRs and the potential for resultant human exposure, we collected 96 plastic kitchen utensils and screened for Br content using a hand-held X-ray fluorescence (XRF) spectrometer. Only 3 out of 27 utensils purchased after 2011 contained detectable concentrations of Br (≥3μg/g). In contrast, Br was detected in 31 out of the 69 utensils purchased before 2011. Eighteen utensils with Br content higher than 100μg/g, and 12 new utensils were selected for GC-MS analysis of BFRs. BFRs targeted were polybrominated diphenyl ethers (PBDEs) BDE-28, 47, 99, 100, 153, 154, 183 and 209, and novel BFRs (NBFRs) pentabromoethylbenzene (PBEB), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), bis(2-ethylhexyl)-3,4,5,6-tetrabromo-phthalate (BEH-TEBP) and decabromodiphenyl ethane (DBDPE). The ability of XRF to act as a surrogate metric of BFR concentration was indicated by a significant (Spearman coefficient=0.493; p=0.006) positive relationship between Br and ΣBFR concentration. Measurements of ΣBFRs were always exceeded by those of Br. This may be due partly to the presence of BFRs not targeted in our study and also to reduced extraction efficiency of BFRs from utensils. Of our target BFRs, BDE-209 was the most abundant one in most samples, but an extremely high concentration (1000μg/g) of BTBPE was found in one utensil. Simulated cooking experiments were conducted to investigate BFR transfer from selected utensils (n=10) to hot cooking oil, with considerable transfer (20% on average) observed. Estimated median exposure via cooking with BFR contaminated utensils was 60ng/day for total BFRs. In contrast, estimated

  4. Evaluation of the flammability and thermal properties of a new flame retardant coating applied on polyester fabric

    Directory of Open Access Journals (Sweden)

    A.A. Younis

    2016-06-01

    Full Text Available The objective of this research was to investigate the effect of non-durable flame retardant (NDFR coating of samples of polyester fabric untreated and treated with UV/Ozone for different periods. For this purpose, these samples were tested by Fourier transform infrared (FTIR spectroscopy, thermal analysis tests as thermo-gravimetric analysis (TGA and differential scanning calorimeter (DSC. The ignition test was applied using limiting oxygen index (LOI, flame chamber (UL/94. Results indicated that both AZ2 (dried at room temperature and AZ8–12 (dried at 80 °C for 30 min after coating with non-durable fire retardant (NDFR coating polyester samples have significantly decreased the rate of burning and increased the limiting oxygen index.

  5. A robust and stretchable superhydrophobic PDMS/PVDF@KNFs membrane for oil/water separation and flame retardancy.

    Science.gov (United States)

    Li, Deke; Gou, Xuelian; Wu, Daheng; Guo, Zhiguang

    2018-04-05

    The wide application of superhydrophobic membranes has been limited due to their complicated preparation technology and weak durability. Inspired by the mechanical flexibility of nanofibrous biomaterials, nanofibrils have been successfully generated from Kevlar, which is one of the strongest synthetic fibers, by appropriate hydrothermal treatment. In this study, a robust superhydrophobic PDMS/PVDF@KNFs membrane is prepared via a simple one-step process and subsequent curing without combination with inorganic fillers. The as-prepared PDMS/PVDF@KNFs membrane not only shows efficient oil/water separation ability and oil absorption capacity but also has excellent superhydrophobicity stability after deformation. The resultant membrane shows stretchability, flexibility and flame retardance because of the reinforcing effect and the excellent flame retardancy of Kevlar. We believe that this simple fabrication of PDMS/PVDF@KNFs has promising applications in filtering membranes and wearable devices.

  6. The Effect of Ultrafine Magnesium Hydroxide on the Tensile Properties and Flame Retardancy of Wood Plastic Composites

    Directory of Open Access Journals (Sweden)

    Zhiping Wu

    2014-01-01

    Full Text Available The effect of ultrafine magnesium hydroxide (UMH and ordinary magnesium hydroxide (OMH on the tensile properties and flame retardancy of wood plastic composites (WPC were investigated by tensile test, oxygen index tester, cone calorimeter test, and thermogravimetric analysis. The results showed that ultrafine magnesium hydroxide possesses strengthening and toughening effect of WPC. Scanning electron micrograph (SEM of fracture section of samples provided the positive evidence that the tensile properties of UMH/WPC are superior to that of WPC and OMH/WPC. The limited oxygen index (LOI and cone calorimeter test illustrated that ultrafine magnesium hydroxide has stronger flame retardancy and smoke suppression effect of WPC compared to that of ordinary magnesium hydroxide. The results of thermogravimetric analysis implied that ultrafine magnesium hydroxide can improve the char structure which plays an important role in reducing the degradation speed of the inner matrix during combustion process and increases the char residue at high temperature.

  7. Advanced Morphological — Behavioral Test Platform Reveals Neurodevelopmental Defects in Embryonic Zebrafish Exposed to Comprehensive Suite of Halogenated and Organophosphate Flame Retardants

    Science.gov (United States)

    Noyes, Pamela D.; Haggard, Derik E.; Gonnerman, Greg D.; Tanguay, Robert L.

    2015-01-01

    The increased use of flammable plastics and electronic devices along with stricter fire safety standards has led to the heavy use of flame retardant chemicals in many consumer, commercial, and industrial products. Although flame retardant use has increased, a great deal of uncertainty surrounds their safety with some evidence showing toxicity and risk to human and environmental health. Recent efforts have focused on designing high-throughput biological platforms with nonmammalian models to evaluate and prioritize chemicals with limited hazard information. To complement these efforts, this study used a new morphological and behavioral testing platform with embryonic zebrafish to characterize the developmental toxicity of 44 halogenated and organophosphate flame retardants, including several of their known metabolites. Zebrafish were exposed to flame retardants from 6 to 120 h post fertilization (hpf) across concentrations spanning 4 orders of magnitude (eg, 6.4 nM to 64 µM). Flame retardant effects on survival and development were evaluated at 24 and 120 hpf, and neurobehavioral changes were measured using 2 photomotor response (PMR) assays. Compared to controls, 93% (41/44) of flame retardants studied elicited adverse effects among one or more of the bioassays and concentrations tested with the aryl phosphate ester (APE)-based mono-isopropylated triaryl phosphate and the brominated-bisphenol-A analog tetrabromobisphenol-A producing the greatest array of malformations. Hierarchical clustering showed that APE flame retardants with isopropyl, butyl, and cresyl substituents on phenyl rings clustered tightly and were particularly potent. Both PMR assays were highly predictive of morphological defects supporting their use as nonlethal means of evaluating teratogenicity that could allow for additional evaluations of long-term or delayed effects in older animals. Taken together, evidence presented here indicates that zebrafish neurodevelopment is highly sensitive to

  8. Prenatal Exposure to Organohalogens, Including Brominated Flame Retardants, Influences Motor, Cognitive, and Behavioral Performance at School Age

    OpenAIRE

    Roze, Elise; Meijer, Lisethe; Bakker, Attie; Van Braeckel, Koenraad N.J.A.; Sauer, Pieter J.J.; Bos, Arend F.

    2009-01-01

    Background Organohalogen compounds (OHCs) are known to have neurotoxic effects on the developing brain. Objective We investigated the influence of prenatal exposure to OHCs, including brominated flame retardants, on motor, cognitive, and behavioral outcome in healthy children of school age. Methods This study was part of the prospective Groningen infant COMPARE (Comparison of Exposure-Effect Pathways to Improve the Assessment of Human Health Risks of Complex Environmental Mixtures of Organoha...

  9. Chlorinated organophosphate and “legacy” brominated flame retardants in UK waste soft furnishings: A preliminary study

    Directory of Open Access Journals (Sweden)

    William A. Stubbings

    2016-12-01

    Full Text Available The Furniture and Furnishings (Fire Safety Regulations 1988 is the major driver for the use of chemical flame retardants (FRs in soft furnishings marketed in the UK. While these regulations specify the level of flame retardancy required, they do not specify how such levels should be achieved. Consequently, it remains unclear which FRs are present in UK soft furnishings. This is important not only to help assess what FRs we may be exposed to currently, but which FRs are currently entering the waste stream with concomitant potential for release into the environment. To address this data gap, concentrations of polybrominated diphenyl ethers (PBDEs, hexabromocyclododecane (HBCDD and a range of chlorinated organophosphate flame retardants (OPFRs were measured in samples of domestic and office waste soft furnishings products entering the UK waste stream in 2011 and 2012. This preliminary study measured the FR content of: carpets (n = 4, curtains (n = 7, mattress fabrics (n = 2, furniture foam (n = 9, and furniture upholstery textiles (n = 10. Polybrominated diphenyl ethers (PBDEs and hexabromocyclododecane (HBCDD were not found at significant concentrations (below detection limits in most samples in any of the twenty two analysed products. In contrast, 7 of the 9 furniture foam samples were treated with tris(2-chloroisopropylphosphate (TCIPP at a mean concentration of 1.9% w/w, with another single foam sample containing tris(1,3-dichloroisopropylphosphate (TDCIPP and tris(2-chloroethylphosphate (TCEP at 1.1 and 0.5% respectively. By comparison, PBDE concentrations are within the range reported previously for UK indoor dust [18], rather than the percent by weight levels required to impart flame retardancy.

  10. Synthesis of a Novel Phosphorus-Containing Flame Retardant Curing Agent and Its Application in Epoxy Resins.

    Science.gov (United States)

    Zhang, Hongkun; Xu, Miaojun; Li, Bin

    2016-03-01

    A novel phosphorus-containing compound diphenyl-(2,5-dihydroxyphenyl)-phosphine oxide defined as DPDHPPO was synthesized and used as flame retardant and curing agent for epoxy resins (EP). The chemical structure was well characterized by Fourier transform infrared (FTIR) spectroscopy, 1H, 13C and 31P nuclear magnetic resonance. The flame retardant properties, combusting performances and thermal degradation behaviors of the cured epoxy resins were investigated by limiting oxygen index (LOI), vertical burning tests (UL-94), cone calorimeter and thermogravimetric analysis (TGA) tests. The morphologies and chemical compositions of char residues for cured epoxy resins were investigated by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), respectively. The water resistant properties were evaluated by putting the samples into distilled water at 70 degrees C for 168 h. The results revealed that the EP/40 wt% DPDHPPO/60 wt% PDA thermosets successfully passed UL-94 V-0 flammability rating and the LOI value was as high as 31.9%. The cone tests results revealed that the incorporation of DPDHPPO efficiently reduced the combustion parameters of epoxy resins thermosets, such as heat release rate (HRR), total heat release (THR) and so on. The TGA results indicated that the introduction of DPDHPPO promoted epoxy resins matrix decomposed ahead of time compared with that of pure EP and led to a higher char yield and thermal stability at high temperature. The morphological structures and analysis of XPS of char residues revealed that DPDHPPO benefited to the formation of a sufficient, compact and homogeneous char layer with rich flame retardant elements on the epoxy resins materials surface during combustion. After water resistance tests, EP/40 wt% DPDHPPO/60 wt% PDA thermosets still remained excellent flame retardancy, the moisture absorption of epoxy resins thermosets decreased with the increase of DPDHPPO contents in the thermosets due to the existing

  11. Flammability of Cellulose-Based Fibers and the Effect of Structure of Phosphorus Compounds on Their Flame Retardancy

    Directory of Open Access Journals (Sweden)

    Khalifah A. Salmeia

    2016-08-01

    Full Text Available Cellulose fibers are promoted for use in various textile applications due their sustainable nature. Cellulose-based fibers vary considerably in their mechanical and flammability properties depending on their chemical composition. The chemical composition of a cellulose-based fiber is further dependent on their source (i.e., seed, leaf, cane, fruit, wood, bast, and grass. Being organic in nature, cellulose fibers, and their products thereof, pose considerable fire risk. In this work we have compared the flammability properties of cellulose fibers obtained from two different sources (i.e., cotton and peat. Compared to cotton cellulose textiles, peat-based cellulose textiles burn longer with a prominent afterglow which can be attributed to the presence of lignin in its structure. A series of phosphoramidates were synthesized and applied on both cellulose textiles. From thermogravimetric and pyrolysis combustion flow analysis of the treated cellulose, we were able to relate the flame retardant efficacy of the synthesized phosphorus compounds to their chemical structure. The phosphoramidates with methyl phosphoester groups exhibited higher condensed phase flame retardant effects on both types of cellulose textiles investigated in this study. In addition, the bis-phosphoramidates exhibited higher flame retardant efficacy compared to the mono-phosphoramidates.

  12. Superior flame retardancy and smoke suppression of epoxy-based composites with phosphorus/nitrogen co-doped graphene.

    Science.gov (United States)

    Feng, Yuezhan; He, Chengen; Wen, Yingfeng; Ye, Yunsheng; Zhou, Xingping; Xie, Xiaolin; Mai, Yiu-Wing

    2018-03-15

    Phosphorus and/or nitrogen doping is an effective method of improving the physical and chemical properties of reduced graphene oxide (rGO). In this work, phosphorus and nitrogen co-doped rGO (PN-rGO), synthesized using a scalable hydrothermal and microwave process, was used as an additive to improve the flame retardancy of epoxy resin (EP) for the first time. Chemical structure and morphology characterization confirmed that the nitrogen and phosphorus atoms were doped into the graphite lattice adopting pyrrolic-N, pyridinic-N, quaternary-N and pyrophosphate and metaphosphate forms. Doping increased the oxidization resistance of rGO and the thermal-oxidative stability of its composites' char, while also improving the catalytic charring ability of polymer. Both effects resulted in the formation of a stable char protective layer during burning and to a significant improvement in flame retardation and smoke suppression in the final composites. The peak heat release rate (PHRR), total heat release (THR) and total smoke production (TSP) for the EP-based composite (containing 5 wt% PN-rGO) decreased by 30.9%, 29.3% and 51.3%, respectively, compared to neat EP. Our work has produced a promising graphene-based flame retardant additive for the mass production of high-performance composites, also expended the application of heteroatom-doped graphene. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Determination of emerging halogenated flame retardants and polybrominated diphenyl ethers in serum by gas chromatography mass spectrometry.

    Science.gov (United States)

    Cequier, Enrique; Marcé, Rosa Maria; Becher, Georg; Thomsen, Cathrine

    2013-10-04

    Emerging flame retardants are used in a great variety of household goods and thus have the potential to pollute our indoor environment. Health concerns regarding exposure to these flame retardants demand new methods to survey their occurrence in humans. This work describes development and optimization of an analytical method comprising solid phase extraction and gas chromatography coupled to mass spectrometry for the determination of besides 15 polybrominated diphenyl ethers, 7 emerging halogenated flame retardants in human serum (1,2-bis[2,4,6-tribromophenoxy] ethane, decabromodiphenyl ethane, hexabromobenzene, Dechlorane Plus(®), hexachlorocyclopentenyl-dibromocyclooctane, dechlorane 602 and 603). The method was thoroughly validated at three spiking levels obtaining averaged recoveries >80% with a RSD of 5% (n=12). Accuracies ranged from 88 to 125% except for DBDPE, which averaged 66% with overall RSD of 11% (n=12). Method limits of detection (MLD) ranged from 0.3 to 5.4 pg/mL serum, except for decabromodiphenyl ether and decabromodiphenyl ethane for which MLDs were 14 and 20 pg/mL serum, respectively. In human serum samples from Norway, we were able to detect and quantify hexabromobenzene, 1,2-bis[2,4,6-tribromophenoxy] ethane, Dechlorane Plus(®), Dechlorane 602 and 603. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Durable flame retardant and antibacterial finishing on cotton fabrics with cyclotriphosphazene/polydopamine/silver nanoparticles hybrid coatings

    Science.gov (United States)

    Li, Yingzhan; Wang, Bijia; Sui, Xiaofeng; Xie, Ruyi; Xu, Hong; Zhang, Linping; Zhong, Yi; Mao, Zhiping

    2018-03-01

    Durable flame retardant and antibacterial hybrid coatings were developed for cotton fabrics via simultaneous polymerization of dopamine and hydrolytic condensation of N3P3[NH(CH2)3Si(OC2H5)3]6. Silver nanoparticles were also introduced to the coatings by in situ reaction of AgNO3 with catechol moieties on polydopamine (PDA) in the absence of any external reducing agents. Energy dispersive spectrometer (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) were employed to study the morphology and constitution of the coatings. Thermal stability and combustion behaviors were characterized with thermogravimetric analysis (TGA) and vertical flammability tests. Considerable flame retardancy was obtained for the modified cotton fabrics, which also exhibited decent antibacterial activities (99.99%) against Gram-positive bacteria S. aureus and Gram-negative bacteria E. coli. The modification was durable with largely intact flame retardancy and antimicrobial properties after 30 washing cycles.

  15. Polyethylene/bentonite clay nanocomposite with flame retardant properties; Nanocompositos de polietileno/argila bentonitica com propriedades antichama

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Sara Verusca de; Araujo, Edcleide Maria; Pereira, Celeste Margarida Correia; Leite, Amanda Melissa Damiao, E-mail: edcleide.araujo@ufcg.edu.br [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Unidade Acadamica de Engenharia de Materiais; Instituto de Engenharia Mecanica e Gestao Industrial (INEGI), Universidade do Porto (UP), Porto (Portugal)

    2017-10-01

    In this research, nanocomposites of high density polyethylene (HDPE) with montmorillonite clay (MMT) and organoclay (OMMT) were prepared by melt intercalation, in order to examine the flame retardant effect of the obtained material. For comparison, a commercial flame retardant product (FRP) was used in the PE matrix. Grafted polyethylene with maleic anhydride (PE-g-MA) was used as a compatibilizer of the systems. HDPE and its systems were evaluated by: X-ray diffraction (XRD), and flammability (UL94HB, oxygen index (LOI) and Cone Calorimetry). The XRD patterns illustrated that probably partial intercalation and exfoliation occurred with the formation of nanocomposite and/or microcomposite. The results obtained for the oxygen index revealed that HDPE and its systems presented flame retardant properties. Through horizontal flammability tests, it was found that the presence of 1% MMT clay reduced 25% of the flammability of HDPE. By Cone Calorimetry was found that the OMMT clay with percentage of 3, 6 and 9% acted reducing the flammability of nanocomposites. (author)

  16. Characterization of brominated flame retardants in construction and demolition waste components: HBCD and PBDEs.

    Science.gov (United States)

    Duan, Huabo; Yu, Danfeng; Zuo, Jian; Yang, Bo; Zhang, Yukui; Niu, Yongning

    2016-12-01

    The vast majority of construction material is inert and can be managed as nonhazardous. However, structures may have either been built with some environmentally unfriendly substances such as brominated flame retardants (BFRs), or have absorbed harmful elements such as heavy metals. This study focuses on end-of-life construction materials, i.e. construction and demolition (C&D) waste components. The aim was to characterize the concentration of extremely harmful substances, primarily BFRs, including hexabromocyclododecane (HBCD) and polybrominateddiphenyl ethers (PBDEs). Results revealed extremely high contents of HBCD and PBDEs in typical C&D waste components, particularly polyurethane foam materials. Policies should therefore be developed for the proper management of C&D waste, with priority for POP-containing debris. The first priority is to develop a classification system and procedures to separate out the harmful materials for more extensive processing. Additionally, identification and quantification of the environmental implications associated with dumping-dominated disposal of these wastes are required. Finally, more sustainable materials should be selected for use in the construction industry. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. A method for the analysis of multiple novel halogenated flame retardants in cow's milk.

    Science.gov (United States)

    Rawn, Dorothea F K; Corrigan, Catherine; Ménard, Cathie; Breton, François; Sun, Wing-Fung

    2016-07-01

    A method was developed for the extraction and analysis of cow's milk to measure 21 halogenated flame retardants (FRs), including individual isomers plus eight methoxy-polybrominated diphenyl ethers (MeO-PBDEs). Extraction was performed using homogenisation with acetone:hexane with size exclusion chromatography followed by adsorption chromatography clean-up. Analysis was undertaken using gas chromatography high-resolution mass spectrometry. The method was validated in fortified cow's milk with FRs and 2-methoxy-PBDE 68 at three levels (low [12.5-1250 pg g(-)(1)], mid [37.5-5000 pg g(-)(1)] and high [400-10 000 pg g(-)(1)]). Additional methoxy-PBDEs were tested at two fortification levels. Isotope dilution was used to correct for losses during sample preparation and average recoveries ranged from 58% (allyl 2,4,6-tribromophenyl ether [ATE]) to 121% (γ-tetrabromoethylcyclohexane (γ-TBECH)). Limits of detection ranged from 0.055 pg g(-)(1) (6-methoxy-PBDE 47) to 38.9 pg g(-)(1) (decabromodiphenylethane (DBDPE)). Matrix effects were overcome through the use of surrogate and performance standards. A single FR (1-bromomethyl-2,3,4,5,6-pentabromobenzene [PBBB]) and two methoxy-PBDEs were detected in commercially available cow's milk collected from local supermarkets in Ottawa, ON, Canada. Detection frequency was < 25% for these compounds and, where present, concentrations were low.

  18. Regional distribution of halogenated organophosphate flame retardants in seawater samples from three coastal cities in China.

    Science.gov (United States)

    Hu, Mengyang; Li, Jun; Zhang, Beibei; Cui, Qinglan; Wei, Si; Yu, Hongxia

    2014-09-15

    Thirteen samples of seawater were collected from Yellow Sea and East China Sea near Qingdao, Lianyungang, and Xiamen, China. They were analyzed for halogenated organophosphorus flame retardants (OPFRs). The compounds selected for detection were Tris(2-chloroethyl) phosphate (TCEP), Tris(2-chloroisopropyl) phosphate (TCPP), Tris (1,3-dichloro-2-propyl) phosphate (TDCPP), and Tris(2,3-dibromopropyl) phosphate (TDBPP). The total concentrations ranged from 91.87 to 1392 ng/L and the mean concentrations of these four chemicals were 134.44, 84.12, 109.28, and 96.70 ng/L, respectively. TCEP exhibited the highest concentrations, although concentrations of TCPP and TDCPP were also fairly high in Lianyungang and Xiamen. Generally, Lianyungang was the most heavily polluted district, with very high concentrations of TCEP at LYG-2 (550.54 ng/L) and LYG-4 (617.92 ng/L). The main sources of halogenated OPFRs were municipal and industrial effluents of wastewater treatment plants in the nearby economic and industrial zones. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Measurement and human exposure assessment of brominated flame retardants in household products from South China.

    Science.gov (United States)

    Chen, She-Jun; Ma, Yun-Juan; Wang, Jing; Tian, Mi; Luo, Xiao-Jun; Chen, Da; Mai, Bi-Xian

    2010-04-15

    Brominated flame retardants (BFRs), polybrominated diphenyl ethers (PBDEs), and decabromodiphenyl ethane (DBDPE) were examined in household products in the Pearl River Delta, South China, including electronic appliances, furniture and upholstery, car interiors, and raw materials for electronics. The concentrations of PBDEs derived from penta-BDE mixture were much lower (electronic products and their reuse might be also a potential important source of discontinued PBDEs to the environment. DBDPE was found in 20.0% of all the samples, ranging from 311 to 268,230 ng/g. PBDE congener profiles in both the household products and raw materials suggest that some less brominated BDEs in the environment may be derived from the decomposition of higher brominated PBDEs in PBDE-containing products in process of the manufacturing, use and/or recycling. Human exposure to PBDEs from household products via inhalation ranged from 175 to 612 pg/kg bw day, accounting for a small proportion of the total daily exposure via indoor inhalation. Despite the low deleterious risk associated with household products with regard to PBDEs, they are of special concern because of the relatively higher exposures observed for young children and further work is required. 2009 Elsevier B.V. All rights reserved.

  20. Degradation of brominated flame retardant in computer housing plastic by supercritical fluids.

    Science.gov (United States)

    Wang, Yanmin; Zhang, Fu-Shen

    2012-02-29

    The degradation process of brominated flame retardant (BFR) and BFR-containing waste computer housing plastic in various supercritical fluids (water, methanol, isopropanol and acetone) was investigated. The results showed that the debromination and degradation efficiencies, final products were greatly affected by the solvent type. Among the four tested solvents, isopropanol was the most suitable solvent for the recovery of oil from BFR-containing plastic for its (1) excellent debromination effectiveness (debromination efficiency 95.7%), (2) high oil production (60.0%) and (3) mild temperature and pressure requirements. However, in this case, the removed bromine mostly existed in the oil. Introduction of KOH into the sc-isopropanol could capture almost all the inorganic bromine from the oil thus bromine-free oil could be obtained. Furthermore, KOH could enhance the depolymerization of the plastic. The obtained oil mainly consisted of single- and duplicate-ringed aromatic compounds in a carbon range of C9-C17, which had alkyl substituents or aliphatic bridges, such as butyl-benzene, (3-methylbutyl)-benzene, 1,1'-(1,3-propanediyl)bis benzene. Phenol, alkyl phenols and esters were the major oxygen-containing compounds in the oil. This study provides an efficient approach for debromination and simultaneous recovering valuable chemicals from BFR-containing plastic in e-waste. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. In vitro screening of the endocrine disrupting potency of brominated flame retardants and their metabolites

    Energy Technology Data Exchange (ETDEWEB)

    Hamers, T.; Kamstra, J.H. [Inst. for Environmental Studies (IVM), Amsterdam (Netherlands); Sonneveld, E. [BioDetection Systems (BDS), Amsterdam (Netherlands); Murk, A.J. [Wageningen Univ., Toxicology Group, Wageningen (Netherlands); Zegers, B.N.; Boon, J.P. [Royal Netherlands Inst. for Sea Research (NIOZ), Den Burg (Netherlands); Brouwer, A. [Umea Univ., Umea (Sweden)

    2004-09-15

    Substantial evidence is recently becoming available that brominated flame retardants (BFRs) are potential endocrine disruptors. The toxicological profile of BFRs, however, is too incomplete and insufficient to perform human and ecological risk assessment. To fill these gaps, the EU funded research program FIRE was started in December 2002. This program aims at the identification and toxicological characterization of the most potent and environmentally relevant BFRs and their possible risk for human and wildlife health. As part of a hazard identification approach, twenty seven BFRs have been selected within the framework of FIRE for pre-screening their endocrinedisrupting potencies. Selection of test compounds was based on a maximal variation in physicochemical characteristics of BFRs within the test set, allowing the establishment of quantitative structure-activity relationships (QSARs). In addition, environmental relevance (e.g. high production volumes and persistence) and availability for testing were used as selection criteria. BFRs were tested in seven different in vitro bioassays for their potency to interfere via estrogenic, thyroidal, androgenic, progestagenic, and Ah-receptor mediated pathways. Metabolisation rates of BFRs were determined using phenobarbital-induced rat liver microsomes. Finally, the endocrine disrupting potency of the metabolites was determined in the same in vitro bio-assays and compared to the potency of the parent compounds.

  2. Organophosphorus flame retardants in mangrove sediments from the Pearl River Estuary, South China.

    Science.gov (United States)

    Hu, Yong-Xia; Sun, Yu-Xin; Li, Xiao; Xu, Wei-Hai; Zhang, Ying; Luo, Xiao-Jun; Dai, Shou-Hui; Xu, Xiang-Rong; Mai, Bi-Xian

    2017-08-01

    Forty-eight surface sediments were collected from three mangrove wetlands in the Pearl River Estuary (PRE) of South China to investigate the distribution of organophosphorus flame retardants (OPFRs) and the relationship between OPFRs and microbial community structure determined by phospholipid fatty acid. Concentrations of ΣOPFRs in mangrove sediments of the PRE ranged from 13.2 to 377.1 ng g -1 dry weight. Levels of ΣOPFRs in mangrove sediments from Shenzhen and Guangzhou were significantly higher than those from Zhuhai, indicating that OPFRs were linked to industrialization and urbanization. Tris(chloropropyl)phosphate was the predominant profile of OPFRs in mangrove sediments from Shenzhen (38.9%) and Guangzhou (35.0%), while the composition profile of OPFRs in mangrove sediments from Zhuhai was dominated by tris(2-chloroethyl) phosphate (25.5%). The mass inventories of OPFRs in the mangrove sediments of Guangzhou, Zhuhai and Shenzhen were 439.5, 133.5 and 662.3 ng cm -2 , respectively. Redundancy analysis revealed that OPFRs induced a shift in the structure of mangrove sediment microbial community and the variations were significantly correlated with tris(1,3-dichloro-2-propyl)phosphate and tris(2-butoxyethyl) phosphate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Soil contamination by brominated flame retardants in open waste dumping sites in Asian developing countries.

    Science.gov (United States)

    Eguchi, Akifimi; Isobe, Tomohiko; Ramu, Karri; Tue, Nguyen Minh; Sudaryanto, Agus; Devanathan, Gnanasekaran; Viet, Pham Hung; Tana, Rouch Seang; Takahashi, Shin; Subramanian, Annamalai; Tanabe, Shinsuke

    2013-03-01

    In Asian developing countries, large amounts of municipal wastes are dumped into open dumping sites each day without adequate management. This practice may cause several adverse environmental consequences and increase health risks to local communities. These dumping sites are contaminated with many chemicals including brominated flame retardants (BFRs) such as polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs). BFRs may be released into the environment through production processes and through the disposal of plastics and electronic wastes that contain them. The purpose of this study was to elucidate the status of BFR pollution in municipal waste dumping sites in Asian developing countries. Soil samples were collected from six open waste dumping sites and five reference sites in Cambodia, India, Indonesia, Malaysia, and Vietnam from 1999 to 2007. The results suggest that PBDEs are the dominant contaminants in the dumping sites in Asian developing countries, whereas HBCD contamination remains low. Concentrations of PBDEs and HBCDs ranged from ND to 180 μg/kg dry wt and ND to 1.4 μg/kg dry wt, respectively, in the reference sites and from 0.20 to 430 μg/kg dry wt and ND to 2.5 μg/kg dry wt, respectively, in the dumping sites. Contamination levels of PBDEs in Asian municipal dumping sites were comparable with those reported from electronic waste dismantling areas in Pearl River delta, China. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Thermal properties and flame retardancy of an ether-type UV-cured polyurethane coating

    Directory of Open Access Journals (Sweden)

    2010-09-01

    Full Text Available A new UV-reactive monomer piperazine-N,N′-bis(acryloxyethylaryl-phosphoramidate (N-PBAAP containing phosphorus and nitrogen was synthesized and used as flame retardant for an ether-type UV-cured polyurethane acrylate (PUA coating. The thermal properties of the PUA films were investigated by thermogravimetric analysis (TGA in air and nitrogen atmosphere. The TGA results showed that the incorporation of N-PBAAP can obviously enhance the char residue of the PUA coatings. From the TGA and real time Fourier transformed infrared spectroscopy (RT-FTIR results, different degradation behaviors were observed in the PUA coatings with different N-PBAAP content. The combustibility of the PUA coatings was evaluated by microscale combustion calorimeter (MCC. The MCC results revealed that the addition of NPBAAP in the coatings can significantly reduce the peak Heat Release Rate (pHRR, Heat Release Capacity (HRC and the Total Heat Release (THR of the samples. Furthermore, dynamical mechanical thermal analysis (DMA was employed to examine the viscoelastic properties of the PUA films. It was found that the incorporation of N-PBAAP in the formulation can bring in more functional groups to the coatings, which results in an increase of the glass transition temperature (Tg and cross linking density (XLD of the films.

  5. Five-year trends of selected halogenated flame retardants in the atmosphere of Northeast China

    Energy Technology Data Exchange (ETDEWEB)

    Li, Wen-Long; Liu, Li-Yan; Song, Wei-Wei; Zhang, Zi-Feng; Qiao, Li-Na [International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Ma, Wan-Li, E-mail: mawanli002@163.com [International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Li, Yi-Fan, E-mail: ijrc_pts_paper@yahoo.com [International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); IJRC-PTS-NA, Toronto M2N 6X9 (Canada)

    2016-01-01

    This study collected 227 pairs of gas phase and particle phase air samples in a typical urban city of Northeast China from 2008 to 2013. Four alternative halogenated flame retardants for polybrominated diphenyl ethers (PBDEs) were analyzed, namely 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (EHTBB), bis (2-ethylhexyl) tetrabromophthalate (BEHTBP), syn-dechlorane plus (syn-DP) and anti-dechlorane plus (anti-DP). The average concentrations for EHTBB and BEHTBP were 5.2 ± 20 and 30 ± 200 pg/m{sup 3}, respectively, while for syn-DP and anti-DP were 1.9 ± 5.1 and 5.8 ± 18 pg/m{sup 3}, respectively. Generally, they were frequently detected in the particle phase, and the gas/particle partitioning suggested they were the maximum partition chemicals. The fractional abundance of EHTBB (f{sub EHTBB}) and syn-DP (f{sub syn}) were comparable with those in other studies. Strong local sources were identified based on the air parcel backward trajectories and the potential source contribution function. The concentrations of these chemicals were significantly increased during this sampling campaign, possibly suggesting their increasing usages from 2008 to 2013 in China. - Highlights: • Five-year air samples were analyzed for four alternative HFRs. • BEHTBP and DP were frequently detected in the particle phase. • Local and nearby city sources of these HFRs were suggested. • Concentrations of these HFRs were significantly increased in the five-year period.

  6. Dermal bioaccessibility of flame retardants from indoor dust and the influence of topically applied cosmetics.

    Science.gov (United States)

    Pawar, Gopal; Abdallah, Mohamed Abou-Elwafa; de Sáa, Eugenia Villaverde; Harrad, Stuart

    2017-01-01

    Despite extensive literature on their potential adverse health effects, there is a lack of information on human dermal exposure to organic flame retardant chemicals (FRs). This study applies an in vitro physiologically based extraction test to provide new insights into the dermal bioaccessibility of various FRs from indoor dust to synthetic sweat/sebum mixture (SSSM). The bioaccessible fractions of α-, β- and γ-hexabromocyclododecane (HBCD) and tetrabromobisphenol A (TBBPA) to 1:1 (sweat/sebum) mixture were 41%, 47%, 50% and 40%, respectively. For Tris-2-chloroethyl phosphate (TCEP), tris (1-chloro-2-propyl) phosphate (TCIPP) and tris-1,3-dichloropropyl phosphate (TDCIPP), bioaccessible fractions were 10%, 17% and 19%. Composition of the SSSM and compound-specific physicochemical properties were the major factors influencing the bioaccessibility of target FRs. Except for TBBPA, the presence of cosmetics (moisturising cream, sunscreen lotion, body spray and shower gel) had a significant effect (Pcosmetics decreased the bioaccessibility of HBCDs from indoor dust, whereas shower gel and sunscreen lotion enhanced the bioaccessibility of target PFRs. Our bioaccessibility data were applied to estimate the internal exposure of UK adults and toddlers to the target FRs via dermal contact with dust. Our worst-case scenario exposure estimates fell far below available health-based limit values for TCEP, TCIPP and TDCIPP. However, future research may erode the margin of safety for these chemicals.

  7. The core-double-shell microcapsules flame retardant: Synthesis and its application for polyvinyl chloride composites

    Science.gov (United States)

    Zhang, Bin; Jiang, Yujie; Han, Jian

    2017-12-01

    The core-double-shell microcapsules flame retardant has been regarded as a promising additive for improving the fire safety of PVC. In this article, melamine-formaldehyde resin (MF)/silicon dioxide (SiO2)/zinc hydroxystannate (ZHS) microcapsule was prepared. The effect of synthetic parameters (such as pH, agitation speed, reaction time and reaction temperature) on the morphologies and sizes of the SiO2/ZHS microcapsules were investigated in details. MF/SiO2/ZHS microcapsule was introduced into PVC to prepare biofunctional composites with excellent fire resistance and smoke suppression. The flammability of PVC composites was characterized by limiting oxygen index (LOI), smoke density (SDR), cone calorimeter test. The results showed that the sample containing 16.4% MF/SiO2/ZHS microcapsule (the mass ratio of MF:SiO2:ZHS = 2.5:2:8) achieved the maximal LOI value of 35.6%, minimal SDR value of 21.2%, and significantly decreased the peak heat release rate from 179.7 kW/m2 of neat PVC to 108.3 kW/m2. The thermal behaviors of PVC composites and the morphologies of residues were characterized.

  8. A new brominated polymeric additive for flame retardant glass-filled polybutylene terephthalate

    Science.gov (United States)

    Nir, Z.; Kourtides, D. A.; Parker, J. A.; Bar-Yaacov, Y.; Minke, R.; Touval, I.

    1982-01-01

    Attention is called to the undesirable effects (poor ultraviolet light stability and blooming) sometimes introduced by brominated flame retarders. A brominated polymeric additive (BPA) with little or none of these undesirable side effects is compared with decabromobiphenyl oxide (DBBPO). The additive bears the product name F-2300. It is found to be more easily dispersed than DBBPO. The F-2300 is as effective as the DBBPO in the oxygen index test. The improved efficiency of the F-2300 may be explained by its better dispersion in polybutylene terephthalate (PBT). Glass-filled PBT containing F-2300 is found to be more resistant to UV degradation than DBBPO-containing formulas. Formulations with F-2300 therefore have a longer useful outdoor life. F-2300 is a diglycidyl-type polymer containing 50 percent aromatically bound bromine. Its melting point is 112 C, and it is stable up to 372 C. It is pointed out that since its melts at a relatively low temperature, it can be introduced into the formulation as a large agglomerate and still be dispersed evenly throughout the polymer.

  9. Photolysis of brominated flame retardants in textiles exposed to natural sunlight.

    Science.gov (United States)

    Kajiwara, Natsuko; Desborough, Jennifer; Harrad, Stuart; Takigami, Hidetaka

    2013-03-01

    Photolytic transformation profiles of technical hexabromocyclododecane (HBCD) and technical decabromodiphenyl ether (DecaBDE) in flame-retarded textiles exposed to natural sunlight were compared. Textiles that contained approximately 4% HBCDs by weight showed no substantial loss of any of the HBCD diastereomers during the entire exposure period (371 days), indicating that they were resistant to sunlight, that is, that debromination and isomerization of HBCD diastereomers did not occur under the experimental conditions. Exposure of a textile treated with technical DecaBDE resulted in the formation of polybrominated dibenzofurans (PBDFs) as products of photodecomposition of polybrominated diphenyl ethers present in the technical DecaBDE. After 329 days of exposure, the total PBDF concentration reached a maximum of 27 000 ng g(-1), which was approximately 10 times the initial concentration. During the experiment, di- to hexa-BDF congener concentrations increased continuously. Although the concentrations of PBDFs in the textiles were 4–5 orders of magnitude lower than the concentrations of polybrominated diphenyl ethers, it is important to note that PBDFs were formed as a result of sunlight exposure during normal use of products treated with technical DecaBDE.

  10. Brominated flame retardant (BFRs) and Dechlorane Plus (DP) in paired human serum and segmented hair.

    Science.gov (United States)

    Qiao, Lin; Zheng, Xiao-Bo; Yan, Xiao; Wang, Mei-Huang; Zheng, Jing; Chen, She-Jun; Yang, Zhong-Yi; Mai, Bi-Xian

    2018-01-01

    Brominated flame retardants (BFRs) and Dechlorane Plus (DP) were measured in both human hair and paired serum samples from a cohort of university students in South China. Segmental analysis was conducted to explore gender difference and the relationships between the hair and serum. The concentrations of total PBDEs in the hair and serum samples were in a range of 0.28-34.1ng/g dry weight (dw) and 0.16-156ng/g lipid weight (lw), respectively. Concentrations of ∑DPs (sum of the syn-DP and anti-DP isomers) in all hair samples ranged from nd-5.45ng/g dry weight. Concentrations of most PBDEs and decabromodiphenylethane (DBDPE) in distal segments (5-10cm from the scalp) were higher than those in the proximal segments (0-5cm from the scalp) (t-test, p hair. An obvious gender difference was found in the levels of ∑PBDEs using integrated hair samples, while the difference disappeared when considering alone the proximal segments of hair (0-5cm from scalp) for both genders. This paper provides supplement to the current knowledge on sources of BFRs and DPs in hair and declares the importance of segmental analysis. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Kinetics of Brominated Flame Retardant (BFR) Releases from Granules of Waste Plastics.

    Science.gov (United States)

    Sun, Bingbing; Hu, Yuanan; Cheng, Hefa; Tao, Shu

    2016-12-20

    Plastic components of e-waste contain high levels of brominated flame retardants (BFRs), whose releases cause environmental and human health concerns. This study characterized the release kinetics of polybrominated diphenyl ethers (PBDEs) from millimeter-sized granules processed from the plastic exteriors of two scrap computer displays at environmentally relevant temperatures. The release rate of a substitute of PBDEs, 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), from the waste plastics, was reported for the first time. Deca-BDE was the most abundant PBDE congeners in both materials (87-89%), while BTBPE was also present at relatively high contents. The release kinetics of BFRs could be modeled as one-dimensional diffusion, while the temperature dependence of diffusion coefficients was well described by the Arrhenius equation. The diffusion coefficients of BFRs (at 30 °C) in the plastic matrices were estimated to be in the range of 10 -27.16 to 10 -19.96 m 2 ·s -1 , with apparent activation energies between 88.4 and 154.2 kJ·mol -1 . The half-lives of BFR releases (i.e., 50% depletion) from the plastic granules ranged from thousands to tens of billions of years at ambient temperatures. These findings suggest that BFRs are released very slowly from the matrices of waste plastics through molecular diffusion, while their emissions can be significantly enhanced with wear-and-tear and pulverization.

  12. Monitoring of WEEE plastics in regards to brominated flame retardants using handheld XRF.

    Science.gov (United States)

    Aldrian, Alexia; Ledersteger, Alfred; Pomberger, Roland

    2015-02-01

    This contribution is focused on the on-site determination of the bromine content in waste electrical and electronic equipment (WEEE), in particular waste plastics from television sets (TV) and personal computer monitors (PC) using a handheld X-ray fluorescence (XRF) device. The described approach allows the examination of samples in regards to the compliance with legal specifications for polybrominated biphenyls (PBBs) and polybrominated diphenyl ethers (PBDEs) directly after disassembling and facilitates the sorting out of plastics with high contents of brominated flame retardants (BFRs). In all, over 3000 pieces of black (TV) and 1600 pieces of grey (PC) plastic waste were analysed with handheld XRF technique for this study. Especially noticeable was the high percentage of pieces with a bromine content of over 50,000ppm for TV (7%) and PC (39%) waste plastics. The applied method was validated by comparing the data of handheld XRF with results obtained by GC-MS. The results showed the expected and sufficiently accurate correlation between these two methods. It is shown that handheld XRF technique is an effective tool for fast monitoring of large volumes of WEEE plastics in regards to BFRs for on-site measurements. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. In vitro endocrine disruption potential of organophosphate flame retardants via human nuclear receptors.

    Science.gov (United States)

    Kojima, Hiroyuki; Takeuchi, Shinji; Itoh, Toshihiro; Iida, Mitsuru; Kobayashi, Satoshi; Yoshida, Takahiko

    2013-12-06

    Various organophosphate flame retardants (OPFRs) are widely used in building materials, textiles and electric appliances, and have been reported to cause indoor environmental pollution in houses and office buildings. In this study, using cell-based transactivation assays, we characterized the agonistic and/or antagonistic activities of 11 OPFRs against human nuclear receptors; estrogen receptor α (ERα), ERβ, androgen receptor (AR), glucocorticoid receptor (GR), thyroid hormone receptor α1 (TRα1), TRβ1, retinoic acid receptor α (RARα), retinoid X receptor α (RXRα), pregnane X receptor (PXR), peroxisome proliferator-activated receptor α (PPARα), and PPARγ. Of the 11 OPFRs tested, triphenyl phosphate (TPhP) and tricrecyl phosphate (TCP) showed ERα and/or ERβ agonistic activity. In addition, tributyl phosphate (TBP), tris(1,3-dichloro-2-propyl) phosphate (TDCPP), TPhP and TCP showed AR antagonistic activity, and TBP, tris(2-ethylhexyl) phosphate (TEHP), TDCPP, TPhP and TCP showed GR antagonistic activity. Furthermore, we found that seven compounds, TBP, tris(2-chloro-1-methylethyl) phosphate (TCPP), TEHP, tris(2-butoxyethyl) phosphate (TBEP), TDCPP, TPhP, and TCP, display PXR agonistic activity. However, none of test compounds showed agonistic or antagonistic activity against TRα/β, or agonistic activity against RARα, RXRα or PPARα/γ. Taken together, these results suggest that several OPFRs may have potential endocrine disrupting effects via ERα, ERβ, AR, GR and PXR. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  14. Organophosphate Flame Retardants in House Dust from South China and Related Human Exposure Risks.

    Science.gov (United States)

    Tan, Hongli; Peng, Changfeng; Guo, Ying; Wang, Xiaodong; Wu, Yan; Chen, Da

    2017-09-01

    House dust associated with organic pollutants is not only a potential source of pollutants to the outdoor environment, but also a source to human exposure. The present study investigated the occurrence and concentrations of organophosphate flame retardants (OPFRs) in house dust collected from South China dwellings (n = 20). The results revealed a universal presence of most target OPFRs in house dust, with concentrations of ΣOPFRs ranging from 2.06 to 19.95 μg/g. The median concentration of ΣOPFR (9.20 μg/g) was one order of magnitude greater than that of polybrominated diphenyl ethers (0.80 μg/g). The composition of OPFR chemicals in house dust was dominated by chlorinated OPFRs, such as tris(1,3-dichloro-2-propyl) phosphate (TDCPP) and tris(1-chloro-2-propyl) phosphate (TCPP). This compositional pattern was different from what has been reported in indoor dust from many other countries, where tris(2-butoxyethyl) phosphate (TBEP) was generally dominant. The daily intake of OPFRs by adults was estimated to be 1.6 and 4.2 ng/kg body weight/day under average and high exposure scenarios, respectively, and 31.7 and 127 ng/kg body weight/day for toddlers.

  15. QSAR modeling and prediction of the endocrine-disrupting potencies of brominated flame retardants.

    Science.gov (United States)

    Papa, Ester; Kovarich, Simona; Gramatica, Paola

    2010-05-17

    In the European Union REACH regulation, the chemicals with particularly harmful behaviors, such as endocrine disruptors (EDs), are subject to authorization, and the identification of safer alternatives to these chemicals is required. In this context, the use of quantitative structure-activity relationships (QSAR) becomes particularly useful to fill the data gap due to the very small number of experimental data available to characterize the environmental and toxicological profiles of new and emerging pollutants with ED behavior such as brominated flame retardants (BFRs). In this study, different QSAR models were developed on different responses of endocrine disruption measured for several BFRs. The multiple linear regression approach was applied to a variety of theoretical molecular descriptors, and the best models, which were identified from all of the possible combinations of the structural variables, were internally validated for their performance using the leave-one-out (Q(LOO)(2) = 73-91%) procedure and scrambling of the responses. External validation was provided, when possible, by splitting the data sets in training and test sets (range of Q(EXT)(2) = 76-90%), which confirmed the predictive ability of the proposed equations. These models, which were developed according to the principles defined by the Organization for Economic Co-operation and Development to improve the regulatory acceptance of QSARs, represent a simple tool for the screening and characterization of BFRs.

  16. QSAR classification models for the prediction of endocrine disrupting activity of brominated flame retardants.

    Science.gov (United States)

    Kovarich, Simona; Papa, Ester; Gramatica, Paola

    2011-06-15

    The identification of potential endocrine disrupting (ED) chemicals is an important task for the scientific community due to their diffusion in the environment; the production and use of such compounds will be strictly regulated through the authorization process of the REACH regulation. To overcome the problem of insufficient experimental data, the quantitative structure-activity relationship (QSAR) approach is applied to predict the ED activity of new chemicals. In the present study QSAR classification models are developed, according to the OECD principles, to predict the ED potency for a class of emerging ubiquitary pollutants, viz. brominated flame retardants (BFRs). Different endpoints related to ED activity (i.e. aryl hydrocarbon receptor agonism and antagonism, estrogen receptor agonism and antagonism, androgen and progesterone receptor antagonism, T4-TTR competition, E2SULT inhibition) are modeled using the k-NN classification method. The best models are selected by maximizing the sensitivity and external predictive ability. We propose simple QSARs (based on few descriptors) characterized by internal stability, good predictive power and with a verified applicability domain. These models are simple tools that are applicable to screen BFRs in relation to their ED activity, and also to design safer alternatives, in agreement with the requirements of REACH regulation at the authorization step. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Synergistic flame retardant effects between sepiolite and magnesium hydroxide in ethylene-vinyl acetate (EVA matrix

    Directory of Open Access Journals (Sweden)

    2010-04-01

    Full Text Available Some customers are reluctant to change, because the halogen-free solutions may have higher cost. This is one of the reasons that the synergistic effect is always the subject for researchers to pursue. The synergy between sepiolite and magnesium hydroxide (MH in halogen-free flame retardant ethylene-vinyl acetate (EVA copolymer was investigated in the paper through some common facilities, such as limiting oxygen index (LOI, UL-94 test, thermogravimetric analysis (TGA, differential thermal analysis (DTA and cone calorimeter test (CCT. In the wake of the positive results from the LOI and UL-94 tests, the CCT data indicated not only the reduction of heat release rate (HRR and mass loss rates (MLR, but also prolonged ignition time (TTI and depressed smoke release (SR were observed during combustion. Simultaneously, the tensile strength and Young’s modulus of the system were also much better improved with the increase of sepiolite added due to the hydrogen bonds between silanol groups attached to the sepiolite molecules and the ester groups of EVA. The synergistic mechanism has been discussed in the paper in terms of the barrier mechanism in the condensed phase.

  18. Halogenated Natural Products in Dolphins: Brain-Blubber Distribution and Comparison with Halogenated Flame Retardants.

    Science.gov (United States)

    Barón, E; Hauler, C; Gallistl, C; Giménez, J; Gauffier, P; Castillo, J J; Fernández-Maldonado, C; de Stephanis, R; Vetter, W; Eljarrat, E; Barceló, D

    2015-08-04

    Halogenated natural products (MHC-1, TriBHD, TetraBHD, MeO-PBDEs, Q1, and related PMBPs) and halogenated flame retardants (PBDEs, HBB, Dec 602, Dec 603, and DP) in blubber and brain are reported from five Alboran Sea delphinids (Spain). Both HNPs and HFRs were detected in brain, implying that they are able to surpass the blood-brain barrier and reach the brain, which represents a new finding for some compounds, such as Q1 and PMBPs, MHC-1, TriBHD, TetraBHD, or Dec 603. Moreover, some compounds (TetraBHD, BDE-153, or HBB) presented higher levels in brain than in blubber. This study evidence the high concentrations of HNPs in the marine environment, especially in top predators. It shows the importance of further monitoring these natural compounds and evaluating their potential toxicity, when most studies focus on anthropogenic compounds only. While no bioaccumulation was found for ∑HNPs, ∑HFRs increased significantly with body size for both common and striped dolphins. Studies evaluating BBB permeation mechanisms of these compounds together with their potential neurotoxic effects in dolphins are recommended.

  19. Exposure to organophosphate flame retardants of hotel room attendants in Wuhan City, China.

    Science.gov (United States)

    Tao, Yun; Shang, Yinzhu; Li, Jing; Feng, Jingwen; He, Zhenyu; Covaci, Adrian; Wang, Peng; Luo, Jing; Mao, Xiang; Shi, Bin; Hu, Liqin; Luo, Dan; Mei, Surong

    2018-05-01

    Indoor environments provide sources of exposure to organophosphate flame retardants (PFRs), which are artificially synthesized fire-protecting agents used as additives in interior products. As public spaces, hotels are required to meet stricter fire-precaution criteria. As such, room attendants may be exposed to higher levels of PFRs. Our goal was to characterize the exposure of hotel room attendants to PFRs by measuring metabolites in their urine and the corresponding parent PFRs in dust and hand-wipes collected from 27 hotels located in Wuhan City, China. The exposure of the attendants was found to be omnipresent: urinary metabolites of PFRs, such as DPHP (diphenyl phosphate), BDCIPP (bis(1,3-dichloro-2-propyl) phosphate), and DoCP (di-o-cresyl phosphate) & DpCP (di-p-cresyl phosphate) were detected with high frequency (87%, 79% and 87%, respectively). We observed that metabolites in post-shift urine were consistently present at higher levels than those in the first morning voids (p  7 stories) had significantly higher BDCIPP and DPHP concentrations than those from low-rise buildings. A possible reason is that high-rise buildings may use high-grade fireproof building materials to meet stricter fire restrictions. Overall, these results indicate that PFRs exposure in hotels is a contributor to the personal exposure of hotel room attendants. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Risk migration and scientific advance: the case of flame-retardant compounds.

    Science.gov (United States)

    Alcock, Ruth E; Busby, Jerry

    2006-04-01

    It is a common experience that attempts to mitigate a risk lead to new risks, and that risks formerly thought to be of one kind become another kind as technical knowledge evolves. This phenomenon of risk migration suggests that we should take processes over time, rather than specific risks or specific technologies, as a unit of analysis. Several of our existing models of the social management of risks-such as that of social risk amplification-are process models of a kind but are still oriented around the playing out of a particular event or issue. A case study of risk in a group of flame-retardant compounds was used as the basis of a grounded, exploratory analysis of migration processes, the phenomena that influence them, and their consequences. This illustrated how migration naturally occurs from risks that are understood, in which risk bearers have at least some agency, to risks that are not understood and not capable of being influenced by risk bearers. It illustrated how the simultaneous improvement in measuring technology, which detects potential toxins at increasingly small concentrations, combines with intuitive models that ignore concentration to produce conditions likely to generate anxiety. And it illustrated how pressure groups and commercial interests exploit this effect. It also showed how migration makes precautionary action problematic, and how more generally it tends to undermine a society's capacity to cope with risk.

  1. Organophosphate ester (OPE) flame retardants and plasticizers in the open Mediterranean and Black Seas atmosphere.

    Science.gov (United States)

    Castro-Jiménez, Javier; Berrojalbiz, Naiara; Pizarro, Mariana; Dachs, Jordi

    2014-03-18

    The presence of organophosphate ester (OPE) flame retardants and plasticizers has been confirmed for the first time in the atmosphere over the Mediterranean and Black Seas. Atmospheric aerosol samples were collected during two West-East oceanographic cruises across the Mediterranean and in the southwest Black Sea. This comprehensive assessment of baseline concentrations of aerosol phase OPEs, spatial distribution, and related deposition fluxes reveals levels ranging from 0.4 to 6.0 ng m(-3) for the ∑14OPEs and a lack of significant differences among sub-basins. Levels measured across the Mediterranean Sea and in the Black Sea are in the upper range or higher than those from previous reports for the marine atmosphere, presumably due to proximity to sources. From 13 to 260 tons of OPEs are estimated to be annually loaded to the Mediterranean Sea open waters from the atmosphere. Tris-(1-chloro-2-propyl)phosphate (TCPP) was the most abundant compound over the atmosphere of all the Mediterranean and Black Sea sub-basins, and therefore the chemical reaching surface waters at a higher extent by dry deposition. The atmospheric deposition fluxes of phosphorus due to OPE deposition is a significant fraction of known atmospheric inputs of new organic phosphorus (P), suggesting the relevant role that anthropogenic organic pollutants could play in the P cycle.

  2. Five-year trends of selected halogenated flame retardants in the atmosphere of Northeast China.

    Science.gov (United States)

    Li, Wen-Long; Liu, Li-Yan; Song, Wei-Wei; Zhang, Zi-Feng; Qiao, Li-Na; Ma, Wan-Li; Li, Yi-Fan

    2016-01-01

    This study collected 227 pairs of gas phase and particle phase air samples in a typical urban city of Northeast China from 2008 to 2013. Four alternative halogenated flame retardants for polybrominated diphenyl ethers (PBDEs) were analyzed, namely 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (EHTBB), bis (2-ethylhexyl) tetrabromophthalate (BEHTBP), syn-dechlorane plus (syn-DP) and anti-dechlorane plus (anti-DP). The average concentrations for EHTBB and BEHTBP were 5.2 ± 20 and 30 ± 200 pg/m3, respectively, while for syn-DP and anti-DPwere 1.9±5.1 and 5.8±18 pg/m3, respectively. Generally, they were frequently detected in the particle phase, and the gas/particle partitioning suggested they were the maximum partition chemicals. The fractional abundance of EHTBB (fEHTBB) and syn-DP (fsyn)were comparablewith those in other studies. Strong local sources were identified based on the air parcel backward trajectories and the potential source contribution function. The concentrations of these chemicals were significantly increased during this sampling campaign, possibly suggesting their increasing usages from 2008 to 2013 in China.

  3. [Determination and prediction for vapor pressures of organophosphate flame retardants by gas chromatography].

    Science.gov (United States)

    Wang, Qingzhi; Zhao, Hongxia; Wang, Yan; Xie, Qing; Chen, Jingwen; Quan, Xie

    2017-09-08

    Organophosphate flame retardants (OPFRs) are ubiquitous in the environment. To better understand and predict their environmental transport and fate, well-defined physicochemical properties are required. Vapor pressures ( P ) of 14 OPFRs were estimated as a function of temperature ( T ) by gas chromatography (GC), while 1,1,1-trichioro-2,2-bis (4-chlorophenyl) ethane ( p,p '-DDT) was acted as a reference substance. Their log P GC values and internal energies of phase transfer (△ vap H ) ranged from -6.17 to -1.25 and 74.1 kJ/mol to 122 kJ/mol, respectively. Substitution pattern and molar volume ( V M ) were found to be capable of influencing log P GC values of the OPFRs. The halogenated alkyl-OPFRs had lower log P GC values than aryl-or alkyl-OPFRs. The bigger the molar volume was, the smaller the log P GC value was. In addition, a quantitative structure-property relationship (QSPR) model of log P GC versus different relative retention times (RRTs) was developed with a high cross-validated value ( Q 2 cum ) of 0.946, indicating a good predictive ability and stability. Therefore, the log P GC values of the OPFRs without standard substance can be predicted by using their RRTs on different GC columns.

  4. Determination and prediction of octanol-air partition coefficients for organophosphate flame retardants.

    Science.gov (United States)

    Wang, Qingzhi; Zhao, Hongxia; Wang, Yan; Xie, Qing; Chen, Jingwen; Quan, Xie

    2017-11-01

    Organophosphate flame retardants (OPFRs) have attracted wide concerns due to their toxicities and ubiquitous occurrence in the environment. In this work, Octanol-air partition coefficient (K OA ) for 14 OPFRs including 4 halogenated alkyl-, 5 aryl- and 5 alkyl-OPFRs, were estimated as a function of temperature using a gas chromatographic retention time (GC-RT) method. Their log K OA-GC values and internal energies of phase transfer (Δ OA U/kJmol -1 ) ranged from 8.03 to 13.0 and from 69.7 to 149, respectively. Substitution pattern and molar volume (V M ) were found to be capable of influencing log K OA-GC values of OPFRs. The halogenated alkyl-OPFRs had higher log K OA-GC values than aryl- or alkyl-OPFRs. The bigger the molar volume was, the greater the log K OA-GC values increased. In addition, a predicted model of log K OA-GC versus different relative retention times (RRTs) was developed with a high cross-validated value (Q 2 (cum) ) of 0.951, indicating a good predictive ability and stability. Therefore, the log K OA-GC values of the remaining OPFRs can be predicted by using their RRTs on different GC columns. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Effects of organophosphorus flame retardant TDCPP on normal human corneal epithelial cells: Implications for human health.

    Science.gov (United States)

    Xiang, Ping; Liu, Rong-Yan; Li, Chao; Gao, Peng; Cui, Xin-Yi; Ma, Lena Q

    2017-11-01

    Tris(1,3-dichloro-2-propyl) phosphate (TDCPP) is one of the most detected organophosphorus flame retardants (OPFRs) in the environment, especially in indoor dust. Continuous daily exposure to TDCPP-containing dust may adversely impact human cornea. However, its detrimental effects on human corneal epithelium are largely unknown. In this study, we investigated the cell apoptosis in normal human corneal epithelial cells (HCECs) after TDCPP exposure and elucidated the underlying molecular mechanisms. Our data indicated a dose-dependent decrease of cell viability after TDCPP exposure with LC 50 at 202 μg/mL. A concentration-dependent apoptotic sign was observed in HCECs after exposing to ≥2 μg/mL TDCPP. Endoplasmic reticulum stress induction was evidenced by up-regulation of its biomarker genes (ATF-4, CHOP, BiP, and XBP1). Furthermore, alternation of Bcl-2/Bax expression, mitochondrial membrane potential loss, cellular ATP content decrease, and caspase-3 and -9 activity increase were observed after exposing to 2 or 20 μg/mL TDCPP. Taken together, the data implicated the involvement of endoplasmic reticulum stress in TDCPP-induced HCEC apoptosis, probably mediated by mitochondrial apoptotic pathway. Our findings showed TDCPP exposure induced toxicity to human cornea. Due to TDCPP's presence at high levels in indoor dust, further study is warranted to evaluate its health risk on human corneas. Published by Elsevier Ltd.

  6. Maternal transfer of emerging brominated and chlorinated flame retardants in European eels

    Energy Technology Data Exchange (ETDEWEB)

    Sühring, Roxana, E-mail: roxana.suehring@hzg.de [Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research, Institute of Coastal Research, Department for Environmental Chemistry, Max-Planck-Strasse 1, 21502 Geesthacht (Germany); Leuphana University Lüneburg, Institute of Sustainable and Environmental Chemistry, Scharnhorststraße 1, 21335 Lüneburg (Germany); Freese, Marko [Thünen Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg (Germany); Schneider, Mandy [Leuphana University Lüneburg, Institute of Sustainable and Environmental Chemistry, Scharnhorststraße 1, 21335 Lüneburg (Germany); Schubert, Sophia; Pohlmann, Jan-Dag [Thünen Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg (Germany); Alaee, Mehran [Water Science and Technology Directorate, Environment Canada, Burlington, Ontario, L7R4A6 Canada (Canada); Wolschke, Hendrik [Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research, Institute of Coastal Research, Department for Environmental Chemistry, Max-Planck-Strasse 1, 21502 Geesthacht (Germany); Leuphana University Lüneburg, Institute of Sustainable and Environmental Chemistry, Scharnhorststraße 1, 21335 Lüneburg (Germany); Hanel, Reinhold [Thünen Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg (Germany); Ebinghaus, Ralf [Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research, Institute of Coastal Research, Department for Environmental Chemistry, Max-Planck-Strasse 1, 21502 Geesthacht (Germany); Marohn, Lasse [Thünen Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg (Germany)

    2015-10-15

    The European eel (Anguilla anguilla) is regarded as a critically endangered species. Scientists are in agreement that the “quality of spawners” is a vital factor for the survival of the species. This quality can be impaired by parasites, disease and pollution. Especially endocrine disrupting organic chemicals pose a potential threat to reproduction and development of offspring. To our knowledge, the findings in this publication for the first time describe maternal transfer of contaminants in eels. We analysed the concentrations of in total 53 polybrominated diphenyl ethers (PBDEs) and their halogenated substitutes in muscle, gonads and eggs of artificially matured European eels and in muscle and gonads of untreated European eels that were used for comparison. We found evidence that persistent organic pollutants such as PBDEs, as well as their brominated and chlorinated substitutes are redistributed from muscle tissue to gonads and eggs. Concentrations ranged from 0.001 ng g{sup −1} ww for sum Dechlorane metabolites (DPMA, aCL{sub 10}DP, aCl{sub 11}DP) to 2.1 ng g{sup −1} ww for TBA in eggs, 0.001 ng g{sup −1} ww for Dechlorane metabolites to 9.4 ng g{sup −1} ww for TBA in gonads and 0.002 ng g{sup −1} ww for Dechlorane metabolites to 54 ng g{sup −1} ww for TBA in muscle tissue. Average egg muscle ratios (EMRs) for compounds detectable in artificially matured eels from both Schlei Fjord and Ems River ranged from 0.01 for Dechlorane 602 (DDC-DBF) to 10.4 for PBEB. Strong correlations were found between flame retardant concentrations and lipid content in the analysed tissue types, as well as transfer rates and octanol–water partitioning coefficient, indicating that these parameters were the driving factors for the observed maternal transfer. Furthermore, indications were found, that TBP-DBPE, TBP-AE, BATE and TBA have a significant uptake from the surrounding water, rather than just food and might additionally be formed by metabolism or

  7. Fireproofing and heat insulating performance improvement of EG/ATH modified intumescent flame retardant coating treated under Co-60 radiation

    Science.gov (United States)

    Zhang, Yuehong; Luan, Weiling; Jiang, Tao

    2017-12-01

    New intumescent flame retardant (IFR) coatings with different fire retardants were prepared in this paper. Expandable graphite (EG) and Aluminium hydroxide (ATH) were respectively added into the conventional IFR coating system, which included ammonium polyphosphate (APP) / pentaerythritol (PER) / melamine (MEL). The fireproofing time and heat insulating properties of the additives acted as fire retardants were investigated via thermogravimetry analysis (TGA) and fire resistance test of homemade big panel test. The morphology of the char layer structure was achieved by scanning electron microscopy (SEM). The highlight of the paper was that the coating samples were pretreated under Co-60 radiation. The influence of radiation on the fire resistance time and char layer height was investigated. The results showed that the prepared IFR coatings can be used in Co-60 radiation for more than 90 min when encountering fire. It would be a reference for radiation shielding in nuclear environment.

  8. Novel and high volume use flame retardants in US couches reflective of the 2005 PentaBDE phase out.

    Science.gov (United States)

    Stapleton, Heather M; Sharma, Smriti; Getzinger, Gordon; Ferguson, P Lee; Gabriel, Michelle; Webster, Thomas F; Blum, Arlene

    2012-12-18

    California's furniture flammability standard Technical Bulletin 117 (TB 117) is believed to be a major driver of chemical flame retardant (FR) use in residential furniture in the United States. With the phase-out of the polybrominated diphenyl ether (PBDE) FR mixture PentaBDE in 2005, alternative FRs are increasingly being used to meet TB 117; however, it was unclear which chemicals were being used and how frequently. To address this data gap, we collected and analyzed 102 samples of polyurethane foam from residential couches purchased in the United States from 1985 to 2010. Overall, we detected chemical flame retardants in 85% of the couches. In samples purchased prior to 2005 (n = 41) PBDEs associated with the PentaBDE mixture including BDEs 47, 99, and 100 (PentaBDE) were the most common FR detected (39%), followed by tris(1,3-dichloroisopropyl) phosphate (TDCPP; 24%), which is a suspected human carcinogen. In samples purchased in 2005 or later (n = 61) the most common FRs detected were TDCPP (52%) and components associated with the Firemaster550 (FM 550) mixture (18%). Since the 2005 phase-out of PentaBDE, the use of TDCPP increased significantly. In addition, a mixture of nonhalogenated organophosphate FRs that included triphenyl phosphate (TPP), tris(4-butylphenyl) phosphate (TBPP), and a mix of butylphenyl phosphate isomers were observed in 13% of the couch samples purchased in 2005 or later. Overall the prevalence of flame retardants (and PentaBDE) was higher in couches bought in California compared to elsewhere, although the difference was not quite significant (p = 0.054 for PentaBDE). The difference was greater before 2005 than after, suggesting that TB 117 is becoming a de facto standard across the U.S. We determined that the presence of a TB 117 label did predict the presence of a FR; however, lack of a label did not predict the absence of a flame retardant. Following the PentaBDE phase out, we also found an increased number of flame retardants on the

  9. The effect of electron-beam irradiation and halogen-free flame retardants on properties of poly butylene terephthalate

    Science.gov (United States)

    Hooshangi, Zhila; Feghhi, Seyed Amir Hossein; Sheikh, Nasrin

    2015-03-01

    Engineering plastics like Poly (butylene terephthalate) due to their desirable properties have various industrial applications. Neat PBT is highly combustible, so it is necessary to improve significantly its fire retardancy to meet the fire safety requirements. The combustion performance of PBT can be improved by addition of appropriate flame retardant additives. In this study we have investigated the effect of halogen free flame retardants, i.e. melamine and aluminum phosphate, and instantaneously electron beam radiation-induced crosslinking in the presence of Triallyl cyanurate on various properties of PBT. The results of gel content showed that a dose range of 200-400 kGy leads to high cross linked structure in this polymer. Also mechanical experiments showed that its structure became rigid and fragile due to irradiation. Radiation crosslinking of this polymer made its dielectric loss coefficient ten times lower than non-irradiated polymer, but had no effect on its dielectric constant. Moreover the addition of the fire retardant additives as impurity decreased the dielectric loss coefficient. TGA analysis in nitrogen exhibited that irradiation increases char formation and use of the fire retardant additives leads to reduction of onset temperature and formation of higher char quantity than pure PBT. According to the results of UL-94, irradiated samples burned with lower speed and less dripping in vertical and horizontal positions than pure polymer. Finally irradiation of the polymers containing fire retardant additives with a dose of 400 kGy led to self-extinguishing and non-dripping and reach to V-0 level in the UL-94 V.

  10. Effect of Sb2O3 Modified by Various Surface Active Agents on Flame Retardant Properties of PVC Composite

    Directory of Open Access Journals (Sweden)

    XU Jian-lin

    2016-08-01

    Full Text Available Sb2O3 powders were prepared by high energy ball milling using polyethyleneglycol-6000,sodium dodecyl sulfate and OP-10 to modify the surface properties of the powder. The influence of Sb2O3 powders modified by various surface active agents on flame retardant properties of PVC composite materials was studied. The phase composition, morphology and the average particle size of the powders were characterized by XRD and TEM. The particle distribution and flame retardant properties of Sb2O3/PVC composite materials were studied by EDS, limiting oxygen index instrument and vertical burning test. The results show that nanometer Sb2O3 has good dispersion in the PVC matrix because of the higher space steric effect of organic film on the surface of nanometer Sb2O3 when polyethyleneglycol-6000 was used as the surface active agent. While the content of nanometer Sb2O3 is 1.26% in the PVC composite material, the oxygen index of the composite material is 27.1% and the composite material reaches fire retardant grade. Using sodium dodecyl sulfate and OP-10 as surface dispersants, the surface of Sb2O3 powders can not be coated completely. The particle size of Sb2O3 powders are 100nm and 150nm, respectively, The Sb2O3 powders have poor dispersion in the PVC matrix, and even some agglomerating phenomena took place. The oxygen index of Sb2O3/PVC composite materials are 24.7% and 25.3%, respectively, containing 1.26% Sb2O3 powders in Sb2O3/PVC composite material. The materials don't achieve flame retardant level.

  11. Preparation and properties studies of halogen-free flame retardant form-stable phase change materials based on paraffin/high density polyethylene composites

    International Nuclear Information System (INIS)

    Cai Yibing; Wei Qufu; Huang Fenglin; Gao Weidong

    2008-01-01

    The halogen-free flame retardant form-stable phase change materials (PCM) based on paraffin/high density polyethylene (HDPE) composites were prepared by using twin-screw extruder technique. The structures and properties of the form-stable PCM composites based on intumescent flame retardant system with expandable graphite (EG) and different synergistic additives, such as ammonium polyphosphate (APP) and zinc borate (ZB) were characterized by scanning electronic microscope (SEM), thermogravimetric analyses (TGA), dynamic Fourier-transform infrared (FTIR) spectra, differential scanning calorimeter (DSC) and Cone calorimeter test. The TGA results showed that the halogen-free flame retardant form-stable PCM composites produced a larger amount of charred residue at 700 deg. C, although the onset of weight loss of the halogen-free flame retardant form-stable PCM composites occurred at a lower temperature due to the thermal decomposition of flame retardant. The DSC measurements indicated that the additives of flame retardant had little effect on the thermal energy storage property, and the temperatures of phase change peaks and the latent heat of the paraffin showed better occurrence during the freezing process. The dynamic FTIR monitoring results revealed that the breakdowns of main chains (HDPE and paraffin) and formations of various residues increased with increasing thermo-oxidation temperature. It was also found from the Cone calorimeter tests that the peak of heat release rate (PHRR) decreased significantly. Both the decrease of the PHRR and the structure of charred residue after combustion indicated that there was a synergistic effect between the EG and APP, contributing to the improved flammability of the halogen-free flame retardant form-stable PCM composites

  12. Effect of electron beam irradiation and microencapsulation on the flame retardancy of ethylene-vinyl acetate copolymer materials during hot water ageing test

    International Nuclear Information System (INIS)

    Sheng, Haibo; Zhang, Yan; Wang, Bibo; Yu, Bin; Shi, Yongqian; Song, Lei; Kundu, Chanchal Kumar; Tao, Youji; Jie, Ganxin; Feng, Hao; Hu, Yuan

    2017-01-01

    Microencapsulated ammonium polyphosphate (MCAPP) in combination with polyester polyurethane (TPU) was used to flame retardant ethylene-vinyl acetate copolymer (EVA). The EVA composites with different irradiation doses were immersed in hot water (80 °C) to accelerate ageing process. The microencapsulation and irradiation dose ensured positive impacts on the properties of the EVA composites in terms of better dimensional stability and flame retardant performance. The microencapsulation of APP could lower its solubility in water and the higher irradiation dose led to the more MCAPP immobilized in three dimensional crosslinked structure of the EVA matrix which could jointly enhance the flame retardant and electrical insulation properties of the EVA composites. So, the EVA composites with 180 kGy irradiation dose exhibited better dimensional stability than the EVA composites with 120 kGy due to the higher crosslinking degree. Moreover, the higher irradiation dose lead to the more MCAPP immobilizated in crosslinked three-dimensional structure of EVA, enhancing the flame retardancy and electrical insulation properties of the EVA composites. After ageing test in hot water at 80 °C for 2 weeks, the EVA/TPU/MCAPP composite with 180 kGy could still maintain the UL-94 V-0 rating and the limiting oxygen index (LOI) value was as high as 30%. This investigation indicated the flame retardant EVA cable containing MCAPP could achieve stable properties and lower electrical fire hazard risk during long-term hot water ageing test. - Highlights: • Microencapsulated ammonium polyphosphate is prepared by successive sol-gel process. • The higher irradiation dose induces the better dimensional stability for EVA system. • The higher irradiation, the more MCAPP immobilized in EVA crosslinked structure. • The higher irradiation dose enhances the flame retardancy of EVA composites. • The microencapsulated composites demonstrate stable flame retardancy in ageing test.

  13. Brominated flame retardants in breast milk and behavioural and cognitive development at 36 months.

    Science.gov (United States)

    Adgent, Margaret A; Hoffman, Kate; Goldman, Barbara Davis; Sjödin, Andreas; Daniels, Julie L

    2014-01-01

    Polybrominated diphenyl ethers (PBDEs) are persistent flame retardants found in the environment, in household dust, and in humans. Breast feeding is a prominent route of exposure in infancy. PBDEs adversely affect neurodevelopment in animals. Here, we estimate associations between PBDEs in breast milk and behaviour and cognitive skills in children at 36 months of age. We prospectively studied 304 mothers and their children. We measured PBDEs in breast milk collected at 3 months postpartum. At 36 months, we measured child behaviour with the parent-rated Behavioral Assessment System for Children 2 (n = 192), and cognitive skills with the Mullen Scales of Early Learning (n = 184). We analysed data with robust regression. We detected BDE-28, -47, -99, -100, and -153 in >70% of milk samples. For each congener, the highest quartile of breast milk PBDE concentration, vs. the lowest, was associated with more anxious behaviour, after confounder adjustment. Select congeners were associated with increased withdrawal (BDE-28) and improved activity of daily living skills (BDE-153). Cognitive skills tended to be positively associated with PBDEs, especially language and fine motor skills. However, most estimates were imprecise. Here, lactational PBDE exposure was modestly and imprecisely associated with anxiety and withdrawal, but was also associated with improved adaptive and cognitive skills. Positive factors associated with breast feeding may have mitigated some of the hypothesised adverse neurodevelopmental outcomes associated with PBDEs. Further research is needed to inform our understanding of PBDE neurotoxicity and how sources of exposure might confound neurodevelopmental studies. © 2013 John Wiley & Sons Ltd.

  14. Advanced oxidation kinetics of aqueous tri alkyl phosphate flame retardants and plasticizers

    Science.gov (United States)

    Watts, Michael J.; Linden, Karl G.

    2009-01-01

    Tri alkyl phosphate esters are a class of anthropogenic organics commonly found in surface waters of Europe and North America, due to their frequent application as flame retardants, plasticizers, and solvents. Four tri alkyl phosphate esters were evaluated to determine second-order rates of reaction with ultraviolet- and ozone-generated •OH in water. In competition with nitrobenzene in UV irradiated hydrogen peroxide solutions tris(2-butoxyethyl) phosphate (TBEP) was fastest to react with •OH (kOH,TBEP=1.03×1010 M-1s-1), followed sequentially by tributyl phosphate (TBP), tris(2-chloroethyl) phosphate (TCEP), and tris(2-chloroisopropyl) phosphate (TCPP) (kOH,TBEP=6.40×109, kOH,TBEP=5.60×108, & kOH,TBEP=1.98×10 M-1s-1). A two-stage process was used to test the validity of the determined kOH for TBEP and the fastest reacting halogenated alkyl phosphate, TCEP. First, •OH oxidation of TCEP and TBEP, in competition with nitrobenzene, was measured in ozonated hydrogen peroxide solutions. Applying multiple regression analysis, it was determined that the UV-H2O2 and O3-H2O2 data sets were statistically identical for each compound. The subsequent validated kOH were used to predict TCEP and TBEP photodegradation in neutral pH, model surface water after chemical oxidant addition and UV irradiation (up to 1000 mJ/cm2). The insignificant difference, between the predicted TBEP and TCEP photodegradation and a best-fit of the first-order exponential decay function to the observed TBEP and TCEP concentrations with increasing UV fluence, was further evidence of the validity of the determined kOH. TBEP oxidation rates were similar in the surface waters tested. Substantial TCEP oxidation in the model surface water required a significant increase in H2O2. PMID:19475974

  15. Non-PBDE halogenated flame retardants in Canadian indoor house dust: sampling, analysis, and occurrence.

    Science.gov (United States)

    Fan, Xinghua; Kubwabo, Cariton; Rasmussen, Pat E; Wu, Fang

    2016-04-01

    An analytical method was developed for the measurement of 18 novel halogenated flame retardants in house dust. Sample preparation was based on ultrasound-assisted solvent extraction and clean up with solid phase extraction (SPE). Sample extracts were analyzed by gas chromatography-mass spectrometry (GC/MS) operated in electron capture negative ion (ECNI) chemical ionization mode. Baseline data from 351 fresh (active) dust samples collected under the Canadian House Dust Study (CHDS) revealed that five out of 18 target chemicals were present with detection frequencies higher than 90 %. Median (range) concentrations for these five compounds were as follows: 104 (<1.5-13,000) ng/g for 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EHTBB), 8.5 (<1.7-2390) ng/g for 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), 10.2 (<1.7-430) ng/g for hexabromobenzene (HBB), 2.9 (<1.2-1410) ng/g for syn-dechlorane plus (syn-DP) and 5.6 (<1.9-1570) ng/g for anti-dechlorane plus (anti-DP). A comparison of two sampling methods in a subset of 40 homes showed significant positive correlations between samples of "active" dust and samples taken directly from the household vacuum cleaner for all target compounds having median values above their corresponding method detection limits (MDLs). In addition, the method was also applied to the analysis of the targeted compounds in National Institute of Standards and Technology (NIST) standard reference material (SRM 2585, organic contaminants in house dust). Results from the current study could contribute to the potential certification of target chemicals in SRM 2585.

  16. Inhibition of thyroid hormone sulfotransferase activity by brominated flame retardants and halogenated phenolics.

    Science.gov (United States)

    Butt, Craig M; Stapleton, Heather M

    2013-11-18

    Many halogenated organic contaminants (HOCs) are considered endocrine disruptors and affect the hypothalamic-pituitary-thyroid axis, often by interfering with circulating levels of thyroid hormones (THs). We investigated one potential mechanism for TH disruption, inhibition of sulfotransferase activity. One of the primary roles of TH sulfation is to support the regulation of biologically active T3 through the formation of inactive THs. We investigated TH sulfotransferase inhibition by 14 hydroxylated polybrominated diphenyl ethers (OH BDEs), BDE 47, triclosan, and fluorinated, chlorinated, brominated, and iodinated analogues of 2,4,6-trihalogenated phenol and bisphenol A (BPA). A new mass spectrometry-based method was also developed to measure the formation rates of 3,3'-T2 sulfate (3,3'-T2S). Using pooled human liver cytosol, we investigated the influence of these HOCs on the sulfation of 3,3'-T2, a major substrate for TH sulfation. For the formation of 3,3'-T2S, the Michaelis constant (Km) was 1070 ± 120 nM and the Vmax was 153 ± 6.6 pmol min(-1) (mg of protein)(-1). All chemicals investigated inhibited sulfotransferase activity with the exception of BDE 47. The 2,4,6-trihalogenated phenols were the most potent inhibitors followed by the OH BDEs and then halogenated BPAs. The IC50 values for the OH BDEs were primarily in the low nanomolar range, which may be environmentally relevant. In silico molecular modeling techniques were also used to simulate the binding of OH BDE to SULT1A1. This study suggests that some HOCs, including antimicrobial chemicals and metabolites of flame retardants, may interfere with TH regulation through inhibition of sulfotransferase activity.

  17. Reproductive changes in American kestrels (Falco sparverius) in relation to exposure to technical hexabromocyclododecane flame retardant.

    Science.gov (United States)

    Fernie, Kim J; Marteinson, Sarah C; Bird, David M; Ritchie, Ian J; Letcher, Robert J

    2011-11-01

    Recently, the ban of hexabromocyclododecane (HBCD), a high-production-volume flame retardant, was announced in Europe and North America. However, the effects of HCBD remain understudied in birds. The objectives of the present comparative effects study were to determine whether exposure to an HBCD technical mixture (HBCD-TM) altered avian reproductive measures at an environmentally relevant concentration. American kestrels were exposed daily by food to HBCD-TM, i.e., 0.51 µg HBCD/g kestrel/d; exposed kestrels laid eggs that had α-HBCD concentrations (163.5 ± 75.1 ng/g wet wt) tenfold greater than β- and γ-HBCD isomers, an isomer profile and concentrations similar to those of eggs of wild peregrine falcons (Falco peregrinus). Concentrations of HBCD were not detected in the control kestrel eggs. In comparison with controls, the kestrels exposed to HBCD began to lay their eggs 6 d earlier and laid larger clutches of smaller eggs. The size of the eggs was inversely correlated with the in ovo α-HBCD concentrations. The smaller eggs of the HBCD exposed kestrels also lost more weight by midincubation, suggesting increased eggshell porosity since eggshell thickness was comparable. Generally birds that lay more eggs and lay earlier in the breeding season gain the advantage of better hatching and fledging success, yet the kestrels exposed to HBCD failed to have better reproductive success than the control birds. These reproductive changes were a function of HBCD exposure, likely through changes in food consumption, with possible impacts on, for example, reproductive behavior and/or alterations in thyroid hormones. Copyright © 2011 SETAC.

  18. A miniature bird-borne passive air sampler for monitoring halogenated flame retardants.

    Science.gov (United States)

    Sorais, Manon; Rezaei, Ali; Okeme, Joseph O; Diamond, Miriam L; Izquierdo, Ricardo; Giroux, Jean-François; Verreault, Jonathan

    2017-12-01

    Birds have been used intensively as biomonitors of halogenated flame retardants (HFRs), and several studies have reported elevated tissue concentrations and inter-individual variability for these contaminants. While diet is known to be an important exposure pathway for HFRs in birds, it has been suggested that exposure through air may represent an underestimated source of HFRs for certain species. However, a method was not available for measuring the atmospheric exposure of individual birds to HFRs or other semi-volatile contaminants. The goal of this study was to develop a bird-borne passive air sampler (PAS) enabling the determination of individual atmospheric exposure to gas- and particle-phase HFRs using the ring-billed gull (Larus delawarensis) nesting in the Montreal area (QC, Canada). The new miniaturized elliptical-shaped PAS (mean weight: 2.72g) was tested using two sorbent types during three exposure periods (one, two and three weeks). Results showed that PAS using polyurethane foam (PUF) combined with a glass fiber filter collected all major polybrominated diphenyl ethers (PBDEs) and exhibited better performance for collecting highly hydrophobic DecaBDE mixture congeners compared to the PAS using polydimethylsiloxane (PDMS). Emerging HFRs including hexabromobenzene, Dechlorane 604 Component B, and Dechlorane plus (DP) isomers also were sampled by the PUF-based PAS. Sampling rates for most HFRs were comparable between the three exposure periods. This novel bird-borne PAS provides valuable information on the non-dietary exposure of free-ranging birds to HFRs. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Transformation of Flame Retardant Tetrabromobisphenol A by Aqueous Chlorine and the Effect of Humic Acid.

    Science.gov (United States)

    Gao, Yuan; Pang, Su-Yan; Jiang, Jin; Ma, Jun; Zhou, Yang; Li, Juan; Wang, Li-Hong; Lu, Xue-Ting; Yuan, Li-Peng

    2016-09-06

    In this work, it was found that the most widely used brominated flame retardant tetrabromobisphenol A (TBrBPA) could be transformed by free chlorine over a wide pH range from 5 to 10 with apparent second-order rate constants from 138 to 3210 M(-1)·s(-1). A total of eight products, including one quinone-like compound (i.e., 2,6-dibromoquinone), two dimers, and several simple halogenated phenols (e.g., 4-(2-hydroxyisopropyl)-2,6-dibromophenol, 2,6-dibromohydroquinone, and 2,4,6-tribromophenol), were detected by high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) using a novel precursor ion scan (PIS) approach. A tentative reaction pathway was proposed: chlorine initially oxidized TBrBPA leading to the formation of a phenoxy radical, and then this primary radical and its secondary intermediates (e.g., 2,6-dibromo-4-isopropylphenol carbocation) formed via beta-scission subsequently underwent substitution, dimerization, and oxidation reactions. Humic acid (HA) considerably inhibited the degradation rates of TBrBPA by chlorine even accounting for oxidant consumption. A similar inhibitory effect of HA was also observed in permanganate and ferrate oxidation. This inhibitory effect was possibly attributed to the fact that HA competitively reacted with the phenoxy radical of TBrBPA and reversed it back to parent TBrBPA. This study confirms that chlorine can transform phenolic compounds (e.g., TBrBPA) via electron transfer rather than the well-documented electrophilic substitution, which also have implications on the formation pathway of halo-benzoquinones during chlorine disinfection. These findings can improve the understanding of chlorine chemistry in water and wastewater treatment.

  20. Plastics additives in the indoor environment-flame retardants and plasticizers

    International Nuclear Information System (INIS)

    Wensing, M.; Uhde, E.; Salthammer, T.

    2005-01-01

    Phthalic acid esters and phosphororganic compounds (POC) are generally known as semivolatile organic compounds (SVOCs) and are frequently utilized as plasticizers and flame retardants in commercial products. In the indoor environment, both compound groups are released from a number of sources under normal living conditions and accumulate in air and dust. Therefore, inhalation of air and ingestion of house dust have to be considered as important pathways for the assessment of exposure in living habitats. Especially in the case of very young children, the oral and dermal uptake from house dust might be of relevance for risk assessment. A critical evaluation of indoor exposure to phthalates and POC requires the determination of the target compounds in indoor air and house dust as well as emission studies. The latter are usually carried out under controlled conditions in emission test chambers or cells. Furthermore, chamber testing enables the determination of condensable compounds by fogging sampling. In the case of automobiles, specific scenarios have been developed to study material emissions on a test stand or to evaluate the exposure of users while the vehicle is driving. In this review, results from several studies are summarized and compared for seven phthalic esters and eight POC. The available data for room air and dust differ widely depending on investigated compound and compartment. Room air studies mostly include only a limited number of measurements, which makes a statistical evaluation difficult. The situation is much better for house dust measurements. However, the composition of house dust is very inhomogeneous and the result is strongly dependent on the particle size distribution used for analysis. Results of emission studies are presented for building products, electronic equipment, and automobiles. Daily rates for inhalation and dust ingestion of phthalic esters and POC were calculated from 95-percentiles or maximum values. A comparison of the data

  1. In vivo metabolism of organophosphate flame retardants and distribution of their main metabolites in adult zebrafish.

    Science.gov (United States)

    Wang, Guowei; Chen, Hanyan; Du, Zhongkun; Li, Jianhua; Wang, Zunyao; Gao, Shixiang

    2017-07-15

    Understanding the metabolism of chemicals as well as the distribution and depuration of their main metabolites in tissues are essential for evaluating their fate and potential toxicity in vivo. Herein, we investigated the metabolism of six typical organophosphate (OP) flame retardants (tripropyl phosphate (TPRP), tri-n-butyl phosphate (TNBP), tris(2-butoxyethyl) phosphate (TBOEP), tris(2-chloroethyl) phosphate (TCEP), tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) and tri-p-cresyl phosphate (p-TCP)) in adult zebrafish in laboratory at three levels (0, 1/150 LC 50 (environmentally relevant level), and 1/30 LC 50 per OP analog). Twenty main metabolites were detected in the liver of OPs-exposed zebrafish using high resolution mass spectrometry (Q-TOF). The reaction pathways involving scission of the ester bond (hydrolysis), cleavage of the ether bond, oxidative hydroxylation, dechlorination, and coupling with glucuronic acid were proposed, and were further confirmed by the frontier electron density and point charge calculations. Tissue distribution of the twenty metabolites revealed that liver and intestine with the highest levels of metabolites were the most active organs for OPs biotransformation among the studied tissues of intestine, liver, roe, brain, muscle, and gill, which showed the importance of hepatobiliary system (liver-bile-intestine) in the metabolism and excretion of OPs in zebrafish. Fast depuration of metabolites from tissues indicated that the formed metabolites might be not persistent in fish, and easily released into water. This study provides comprehensive information on the metabolism of OPs in the tissue of zebrafish, which might give some hints for the exploration of their toxic mechanism in aquatic life. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Application of polydimethylsiloxane rod extraction to the determination of sixteen halogenated flame retardants in water samples.

    Science.gov (United States)

    Valls-Cantenys, Carme; Villaverde-de-Sáa, Eugenia; Rodil, Rosario; Quintana, José Benito; Iglesias, Mònica; Salvadó, Victòria; Cela, Rafael

    2013-04-03

    An extraction and preconcentration procedure for the determination in water samples of several halogenated flame retardants (FRs), nine brominated diphenyls ethers (BDEs) and seven non-BDE FRs, was developed and validated. The optimised procedure is based on polydimethylsiloxane (PDMS) rods as sorptive extraction material, followed by liquid desorption and gas chromatography coupled to negative chemical ionisation-mass spectrometry (GC-NCI-MS) determination, rendering an efficient and inexpensive method. The final optimised protocol consists of overnight extraction of 100mL of sample solutions containing 40% MeOH and 4% NaCl, followed by a 15-min sonication-assisted desorption with 300 μL of ethyl acetate, solvent evaporation and GC-NCI-MS analysis. Under these conditions, extraction efficiencies in the 9 to 70% range were obtained, leading to enrichment factors between 108 and 840, detection limits in the range from 0.4 to 10 ng L(-1)and RSD values in the 2-23% range. After method validation, different real water samples, including river, ria, sea, landfill leachate, influent and effluent wastewater from an urban sewage treatment plant (STP) and effluent wastewater from a textile industry, were analysed. BDE-47, BDE-99, BDE-100 and BDE-197 were detected in wastewater and landfill leachate samples at concentration levels up to 2887 ng L(-1). Among the non-BDE FRs, bis (2-ethylhexyl)-3,4,5,6-tetrabromo-phthalate (DEHTBP) was detected in surface water samples (sea, river and ria) between 1.3 and 2.2 ng L(-1) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) in the landfill leachate (64 ng L(-1)). Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Urinary Concentrations of Organophosphate Flame Retardant Metabolites and Pregnancy Outcomes among Women Undergoingin VitroFertilization.

    Science.gov (United States)

    Carignan, Courtney C; Mínguez-Alarcón, Lidia; Butt, Craig M; Williams, Paige L; Meeker, John D; Stapleton, Heather M; Toth, Thomas L; Ford, Jennifer B; Hauser, Russ

    2017-08-25

    Evidence from animal studies suggests that exposure to organophosphate flame retardants (PFRs) can disrupt endocrine function and impair embryo development. However, no epidemiologic studies have been conducted to evaluate effects on fertility and pregnancy outcomes. We evaluated associations between urinary concentrations of PFR metabolites and outcomes of in vitro fertilization (IVF) treatment among couples recruited from an academic fertility clinic. This analysis included 211 women enrolled in the Environment And Reproductive Health (EARTH) prospective cohort study (2005-2015) who provided one or two urine samples per IVF cycle. We measured five urinary PFR metabolites [bis(1,3-dichloro-2-propyl) phosphate (BDCIPP), diphenyl phosphate (DPHP), isopropylphenyl phenyl phosphate (ip-PPP), tert-butylphenyl phenyl phosphate (tb-PPP), and bis(1-chloro-2-propyl) phosphate (BCIPP)] using negative electrospray ionization liquid chromatography tandem mass spectrometry (LC-MS/MS). Molar concentrations of the urinary PFR metabolites were summed. We used multivariable generalized linear mixed models to evaluate the association of the PFR metabolites with IVF outcomes, accounting for multiple IVF cycles per woman. Detection frequencies were high for BDCIPP (87%), DPHP (94%), and ip-PPP (80%), but low for tb-PPP (14%) and BCIPP (0%). We observed decreased success for several IVF outcomes across increasing quartiles of both summed and individual PFR metabolites (DPHP and ip-PPP) in our adjusted multivariable models. Significant declines in adjusted means from the lowest to highest quartile of ΣPFR were observed for the proportion of cycles resulting in successful fertilization (10% decrease), implantation (31%), clinical pregnancy (41%), and live birth (38%). Using IVF to investigate human reproduction and pregnancy outcomes, we found that concentrations of some urinary PFR metabolites were negatively associated with proportions of successful fertilization, implantation

  4. Solvent effects on quantitative analysis of brominated flame retardants with Soxhlet extraction.

    Science.gov (United States)

    Zhong, Yin; Li, Dan; Zhu, Xifen; Huang, Weilin; Peng, Ping'an

    2017-05-18

    Reliable quantifications of brominated flame retardants (BFRs) not only ensure compliance with laws and regulations on the use of BFRs in commercial products, but also is key for accurate risk assessments of BFRs. Acetone is a common solvent widely used in the analytical procedure of BFRs, but our recent study found that acetone can react with some BFRs. It is highly likely that such reactions can negatively affect the quantifications of BFRs in environmental samples. In this study, the effects of acetone on the extraction yields of three representative BFRs [i.e., decabrominated diphenyl ether (decaBDE), hexabromocyclododecane (HBCD) and tetrabromobisphenol A (TBBPA)] were evaluated in the Soxhlet extraction (SE) system. The results showed that acetone-based SE procedure had no measureable effect for the recovery efficiencies of decaBDE but could substantially lower the extraction yields for both TBBPA and HBCD. After 24 h of extraction, the recovery efficiencies of TBBPA and HBCD by SE were 93 and 78% with acetone, 47 and 70% with 3:1 acetone:n-hexane, and 82 and 94% with 1:1 acetone:n-hexane, respectively. After 72 h of extraction, the extraction efficiencies of TBBPA and HBCD decreased to 68 and 55% with acetone, 0 and 5% with 3:1 acetone/n-hexane mixtures, and 0 and 13% with 1:1 acetone/n-hexane mixtures, respectively. The study suggested that the use of acetone alone or acetone-based mixtures should be restricted in the quantitative analysis of HBCD and TBBPA. We further evaluated nine alternative solvents for the extraction of the three BFRs. The result showed that diethyl ether might be reactive with HBCD and may not be considered as the alternative to acetone used solvents for the extraction of HBCD.

  5. Organophosphate Ester Flame Retardants and Plasticizers in the Global Oceanic Atmosphere.

    Science.gov (United States)

    Castro-Jiménez, Javier; González-Gaya, Belén; Pizarro, Mariana; Casal, Paulo; Pizarro-Álvarez, Cristina; Dachs, Jordi

    2016-12-06

    Organophosphate esters (OPEs) are widely used as flame retardants and plasticizers and have been detected ubiquitously in the remote atmosphere. Fourteen OPEs were analyzed in 115 aerosol phase samples collected from the tropical and subtropical Atlantic, Pacific, and Indian Oceans during the MALASPINA circumnavigation campaign. OPEs were detected in all samples with concentrations ranging from 360 to 4400 pg m -3 for the sum of compounds. No clear concentration trends were found between the Northern and Southern hemispheres. The pattern was generally dominated by tris(1-chloro-2-propyl) phosphate (TCPP), although tri-n-butyl phosphate (TnBP) had a predominant role in samples close to continents and in those influenced by air masses originating in continents. The dry deposition fluxes of aerosol phase ∑ 14 OPE ranged from 4 to 140 ng m -2 d -1 . An estimation of the OPE gas phase concentration and gross absorption fluxes by using three different sets of physical chemical properties suggested that the atmosphere-ocean diffusive exchange of OPEs could be 2-3 orders of magnitude larger than dry deposition. The associated organic phosphorus inputs coming from diffusive OPE fluxes were estimated to potentially trigger up to 1.0% of the reported primary production in the most oligotrophic oceanic regions. However, the uncertainty associated with these calculations is high and mostly driven by the uncertainty of the physical chemical properties of OPEs. Further constraints of the physical chemical properties and fluxes of OPEs are urgently needed, in order to estimate their environmental fate and relevance as a diffusive source of new organic phosphorus to the ocean.

  6. Distribution of copper, silver and gold during thermal treatment with brominated flame retardants.

    Science.gov (United States)

    Oleszek, Sylwia; Grabda, Mariusz; Shibata, Etsuro; Nakamura, Takashi

    2013-09-01

    The growing consumption of electric and electronic equipment results in creating an increasing amount of electronic waste. The most economically and environmentally advantageous methods for the treatment and recycling of waste electric and electronic equipment (WEEE) are the thermal techniques such as direct combustion, co-combustion with plastic wastes, pyrolysis and gasification. Nowadays, this kind of waste is mainly thermally treated in incinerators (e.g. rotary kilns) to decompose the plastics present, and to concentrate metals in bottom ash. The concentrated metals (e.g. copper, precious metals) can be supplied as a secondary raw material to metal smelters, while the pyrolysis of plastics allows the recovery of fuel gases, volatilising agents and, eventually, energy. Indeed, WEEE, such as a printed circuit boards (PCBs) usually contains brominated flame retardants (BFRs). From these materials, hydrobromic acid (HBr) is formed as a product of their thermal decomposition. In the present work, the bromination was studied of copper, silver and gold by HBr, originating from BFRs, such as Tetrabromobisphenol A (TBBPA) and Tetrabromobisphenol A-Tetrabromobisophenol A diglycidyl ether (TTDE) polymer; possible volatilization of the bromides formed was monitored using a thermo-gravimetric analyzer (TGA) and a laboratory-scale furnace for treating samples of metals and BFRs under an inert atmosphere and at a wide range of temperatures. The results obtained indicate that up to about 50% of copper and silver can evolve from sample residues in the form of volatile CuBr and AgBr above 600 and 1000°C, respectively. The reactions occur in the molten resin phase simultaneously with the decomposition of the brominated resin. Gold is resistant to HBr and remains unchanged in the residue. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Dietary exposure to brominated flame retardants and abnormal Pap test results.

    Science.gov (United States)

    Jamieson, Denise J; Terrell, Metrecia L; Aguocha, Nnenna N; Small, Chanley M; Cameron, Lorraine L; Marcus, Michele

    2011-09-01

    This study examined a possible association of dietary exposure to polybrominated biphenyls (PBBs), a brominated flame retardant, and self-reported abnormal Pap test results and cervical dysplasia as a precursor to cervical cancer. Women in Michigan who ingested contaminated poultry, beef, and dairy products in the early 1970s were enrolled in a population-based cohort study in Michigan. Serum PBB and serum polychlorinated biphenyl (PCB) concentrations were measured. Reproductive history and health information, including Pap test results, were self-reported by participants. Of the women, 23% (223 of 956) reported an abnormal Pap test. In unadjusted analyses, self-reporting an abnormal Pap test was associated with younger age, current smoking (hazard ratio [HR] 1.61, 95% confidence interval [CI] 1.19-2.17), and longer duration of lifetime use of oral contraceptives (≥10 years; HR 1.92, 95% CI 1.21-3.06). When adjusting for PCB exposure, age at the interview, and smoking history, there was a slightly elevated risk of self-reporting an abnormal Pap test among the highly exposed women compared to women with nondetectable PBB concentrations (PBB≥13 μg/L, HR 1.23, 95% CI 0.74-2.06); however, the CI was imprecise. When breastfeeding duration after the initial PBB measurement was taken into account, there was a reduced risk of self-reporting an abnormal Pap test among the highly exposed women who breastfed for ≥12 months (HR 0.41, 95% CI 0.06-3.03; referent group: women with nondetectable PBB concentrations who did not breastfeed). It remains important to evaluate the potential reproductive health consequences of this class of chemicals as well as other potential predictors of abnormal Pap tests.

  8. Leaching characteristics of heavy metals and brominated flame retardants from waste printed circuit boards

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Xiaoyu [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237 (China); Guo, Jie, E-mail: guojie@ecust.edu.cn [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237 (China); Lin, Kuangfei [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237 (China); Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237 (China); Huang, Kai; Deng, Jingjing [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237 (China)

    2013-02-15

    Highlights: ► Cu and Pb were the most leachable heavy metals in WPCBs according to TCLP and SPLP. ► Penta-BDE congeners were dominated in all extracts. ► High dissolved organic matter condition promoted the BFRs leaching rate. ► Leaching from WPCBs was a significant emission source of BFRs in landfill. -- Abstract: Leaching assessment on five heavy metals (copper, zinc, lead, nickel and cadmium) and two brominated flame retardants (BFRs), polybrominated diphenyl ethers (PBDEs) and tetrabromobisphenol A (TBBPA), from waste printed circuit boards (WPCBs) were conducted using various leaching methods. The mean leaching concentrations of copper were the highest in both toxicity characteristic leaching procedures (TCLP) and synthetic precipitation leaching procedures (SPLP) tests at 8.6 mg/L and 1.1 mg/L, while only lead (6.2 mg/L) exceeded the TCLP criteria and Chinese EPA regulatory limit (both 5.0 mg/L). However, PBDEs and TBBPA were not detected in TCLP and SPLP tests. Then the BFRs leaching trends and potential leachabilities were further investigated in actual landfill leachates using a modified method. Leaching characteristics that fast-leaching initially followed by slow-desorption over time were generally observed. In landfill leachate tests, the highest leaching concentrations of PBDEs and TBBPA were determined at 30.39 and 12.27 μg/L. Meanwhile, the highest leaching rates were estimated to reach 0.08% and 1.00%, respectively, which were significantly influenced by the dissolved organic carbon contents of extracts, the hydrophobicities of target BFRs and the specific surface areas of WPCBs materials. These results proved that leaching from WPCBs was a significant emission source of BFRs in landfill and electronic waste recycling dumpsite.

  9. Product screening for sources of halogenated flame retardants in Canadian house and office dust.

    Science.gov (United States)

    Abbasi, Golnoush; Saini, Amandeep; Goosey, Emma; Diamond, Miriam L

    2016-03-01

    Human exposure to halogenated flame retardants (HFRs) such as polybrominated diphenyl ethers (PBDEs) and their replacements, can be related to exposure to indoor dust and direct contact with HFR-containing products. This study aimed to identify electronic products that contributed to HFRs measured in indoor dust and to develop a screening method for identifying HFRs in hard polymer products. Concentrations of 10 PBDEs and 12 halogenated replacements in dust and surface wipe samples of hard polymer casings of electronic products plus Br in the surfaces of those casing measured using X-ray fluorescence (XRF) were analyzed from 35 homes and 10 offices in Toronto (ON, Canada). HFR concentrations in dust and product wipes were positively correlated. Thus, we hypothesize that electronic products with the highest HFR concentrations contribute the most to concentrations in dust, regardless of the volatility of the HFR. Abundant HFRs in dust and product wipes were PBDEs (BDE-47, 99, 100, 153, 154, 183, 209), TDCPP, DBDPE, EH-TBB and BEHTBP. Older CRT TVs had the highest concentration of BDE-209 of all products tested. This was followed by higher concentrations of HFRs in PCs, Audio/Video (A/V) devices, small household appliances (HHAs) and flat screen TVs. The removal of HFRs from polymer surfaces using wipes supports concerns that HFRs could be transferred from these surfaces to hands as a result of direct contact with HFR-containing products. Surface wipe testing shows promise for screening additive HFRs. In comparison, the Br-content obtained using a handheld XRF analyzer did not correspond to concentrations obtained from surface wipe testing. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Concentrations of organophosphate esters and brominated flame retardants in German indoor dust samples.

    Science.gov (United States)

    Brommer, Sandra; Harrad, Stuart; Van den Eede, Nele; Covaci, Adrian

    2012-09-01

    While it is known that the ingestion of indoor dust contributes substantially to human exposure to the recently restricted polybrominated diphenyl ethers (PBDEs), the situation for one class of potential replacements, i.e. organophosphate esters (OPEs), used in a variety of applications including as flame retardants has yet to be fully characterised. In this study, surface dust from twelve different cars from various locations throughout Germany were analysed for eight OPEs, decabromodiphenyl ethane (DBDPE), and eight PBDEs. In five cars, tris-(1,3-dichloro-2-propyl) phosphate (TDCPP) was the dominant compound with concentrations up to 620 μg g(-1) dust. High concentrations of tri-cresyl phosphate (TCP) (up to 150 μg g(-1)) were also detected in two samples of car dust. Dust from ten offices in the same building in Ludwigsburg, Germany was also analysed. In these samples, tri (2-butoxyethyl) phosphate (TBEP) predominated with an average concentration of 7.0 μg g(-1) dust, followed by tris (1-chloro-2-propyl) phosphate (TCPP) at 3.0 μg g(-1) and triphenyl phosphate (TPhP) at 2.5 μg g(-1) dust. Although caution must be exercised given the relatively small database reported here; this study provides evidence that cars and offices from Germany are significantly more contaminated with OPEs than PBDEs. Average concentrations of ΣOPEs were ten times higher in car than in office dust. This is the first study to provide data on a wide range of OPE concentrations in German indoor dust samples.

  11. Heterogeneous OH initiated oxidation: a possible explanation for the persistence of organophosphate flame retardants in air.

    Science.gov (United States)

    Liu, Yongchun; Liggio, John; Harner, Tom; Jantunen, Liisa; Shoeib, Mahiba; Li, Shao-Meng

    2014-01-21

    Heterogeneous reactions between OH radicals and emerging flame retardant compounds coated on inert particles have been investigated. Organophosphate esters (OPEs) including triphenyl phosphate (TPhP), tris-2-ethylhexyl phosphate (TEHP), and tris-1,3-dichloro-2-propyl phosphate (TDCPP) were coated on (NH4)2SO4 particles and exposed to OH radicals in a photochemical flow tube at 298 K and (38.0 ± 2.0) % RH. The degradation of these particle-bound OPEs was observed as a result of OH exposure, as measured using a Time-of-Flight Aerosol Mass Spectrometer. The derived second-order rate constants for the heterogeneous loss of TPhP, TEHP, and TDCPP were (2.1 ± 0.19) × 10(-12), (2.7 ± 0.63) × 10(-12), and (9.2 ± 0.92) × 10(-13) cm(3) molecule(-1) s(-1), respectively, from which approximate atmospheric lifetimes are estimated to be 5.6 (5.2-6.0), 4.3 (3.5-5.6), and 13 (11-14) days. Additional coating of the OPE coated particles with an OH radical active species further increased the lifetimes of these OPEs. These results represent the first reported estimates of heterogeneous reaction rate constants for these species. The results demonstrate that particle bound OPEs are highly persistent in the atmosphere with regard to OH radical oxidation, consistent with the assumption that OPEs can undergo medium or long-range transport, as previously proposed on the basis of field measurements. Finally, these results indicate that future risk assessment and transport modeling of emerging priority chemicals with semi- to low-volatility must consider particle phase heterogeneous loss processes when evaluating environmental persistence.

  12. Flame Retardant Associations Between Children’s Handwipes and House Dust

    Science.gov (United States)

    Stapleton, Heather M.; Misenheimer, John; Hoffman, Kate; Webster, Thomas F.

    2014-01-01

    Polybrominated diphenyl ether (PBDE) flame retardants (FRs) have been ubiquitously detected at high concentrations in indoor environments; however, with their recent phase-out, more attention is being focused on measurements of exposure to alternative FRs such as organophosphate FRs (OPFRs). In our previous research, we found that PBDE residues measured on children’s handwipes were a strong predictor of serum PBDE levels. Here we build upon this research to examine longitudinal changes in PBDEs in indoor dust and children’s handwipes, and explore the associations between handwipes and dust for alternative FRs. Children from our previous study were re-contacted after approximately two years and new samples of indoor dust and handwipes were collected. PBDE dust-levels were significantly correlated between two different sampling rounds separated by two years; however, PBDE levels in handwipes were not correlated, perhaps suggesting that the sources of PBDEs remained relatively constant in the home, but that behavioral differences in children are changing with age and influencing handwipe levels. OPFRs [i.e. tris (1,3-dichloroisopropyl) phosphate (TDCPP), tris(2-chloroethyl) phosphate (TCEP), tris(2-chloroisopropyl) phosphate (TCIPP)], 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB, also known as TBB), di(2-ethylhexyl) tetrabromophthalate (BEH-TEBP, also known as TBPH), and 1,2,5,6,9,10-hexabromocyclododecane (HBCD) were also ubiquitously detected in house dust samples and geometric mean levels were similar to PBDE levels, or higher in the case of the OPFRs. Significant associations between handwipes and house dust were observed for these alternative FRs, particularly for EH-TBB (rs= 0.54; p5 times/day) was associated with lower FR levels in handwipes. Overall these data suggest that exposure to these alternative FRs will be similar to PBDE exposure, and the influence of hand-to-mouth behavior in children’s exposure needs to be further examined to better

  13. Urinary metabolites of organophosphate flame retardants: temporal variability and correlations with house dust concentrations.

    Science.gov (United States)

    Meeker, John D; Cooper, Ellen M; Stapleton, Heather M; Hauser, Russ

    2013-05-01

    A reduction in the use of polybrominated diphenyl ethers (PBDEs) because of human health concerns may result in an increased use of and human exposure to organophosphate flame retardants (OPFRs). Human exposure and health studies of OPFRs are lacking. We sought to define the degree of temporal variability in urinary OPFR metabolites in order to inform epidemiologic study design, and to explore a potential primary source of exposure by examining the relationship between OPFRs in house dust and their metabolites in urine. Nine repeated urine samples were collected from 7 men over the course of 3 months and analyzed for bis(1,3-dichloro-2-propyl) phosphate (BDCPP) and diphenyl phosphate (DPP), metabolites of the OPFRs tris(1,3-dichloro-2-propyl) phosphate (TDCPP) and triphenyl phosphate (TPP), respectively. Intraclass correlation coefficients (ICCs) were calculated to characterize temporal reliability. Paired house dust and urine samples were collected from 45 men. BDCPP was detected in 91% of urine samples, and DPP in 96%. Urinary BDCPP showed moderate-to-strong temporal reliability (ICC range, 0.55-0.72). ICCs for DPP were lower, but moderately reliable (range, 0.35-0.51). There was a weak [Spearman r (r(S)) = 0.31] but significant (p = 0.03) correlation between urinary BDCPP and TDCPP concentrations in house dust that strengthened when nondetects (r(S) = 0.47) were excluded. There was no correlation between uncorrected DPP and TPP measured in house dust (r(S) TDCPP but not TPP. Urinary concentrations of BDCPP and DPP were moderately to highly reliable within individuals over 3 months.

  14. Associations between brominated flame retardants in human milk and thyroid-stimulating hormone (TSH) in neonates.

    Science.gov (United States)

    Eggesbø, Merete; Thomsen, Cathrine; Jørgensen, Jens V; Becher, Georg; Odland, Jon Øyvind; Longnecker, Matthew P

    2011-08-01

    Brominated flame retardants (BFRs) have been in widespread use in a vast array of consumer products since the 1970s. The metabolites of some BFRs show a structural similarity to thyroid hormones and experimental animal studies have confirmed that they may interfere with thyroid hormone homeostasis. A major concern has been whether intrauterine exposure to BFRs may disturb thyroid homeostasis since the fetal brain is particularly susceptible to alterations in thyroid hormones. However, few reports on newborns have been published to date. To evaluate the association between BFRs and neonatal thyroid-stimulating hormone (TSH). We studied six polybrominated diphenyl ethers (PBDEs) measured in milk samples from 239 women who were part of the "Norwegian Human Milk Study" (HUMIS), 2003-2006. Hexabromocyclododecane (HBCD) and BDE-209 were measured in a subset of the women (193 and 46 milk samples, respectively). The milk was sampled at a median of 33 days after delivery. TSH was measured in babies three days after delivery as part of the routine national screening program for early detection of congenital hypothyroidism. Additional information was obtained through the Medical Birth Registry and questionnaires to the mothers. The PBDE concentrations in human milk in Norway were comparable to concentrations reported from other European countries and Asia, but not the US and Canada where levels are approximately one order of higher magnitude. We observed no statistically significant associations between BDE-47, 99, 153, 154, 209 and HBCD in human milk and TSH in models adjusted for possible confounders and other environmental toxicants including polychlorinated biphenyls (PCBs). We did not observe an association between TSH and exposure to HBCD and PBDEs within the exposure levels observed. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Brominated flame retardants and the formation of dioxins and furans in fires and combustion

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Mengmei [State key laboratory of clean energy utilisation, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou (China); Buekens, Alfons [State key laboratory of clean energy utilisation, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou (China); Formerly with Chemical Engineering department, Vrije Universiteit Brussel, Brussels (Belgium); Li, Xiaodong, E-mail: lixd@zju.edu.cn [State key laboratory of clean energy utilisation, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou (China)

    2016-03-05

    Highlights: • BFRs (PBDEs, HBCD and TBBP-A) are the main sources of PBDD/Fs in combustion process. • Precursor formation is the most relevant pathway for PBDD/Fs formation. • Adding bromine into combustion system can enhance the formation of PCDD/Fs. • Primitive recycling of e-waste produces the largest amounts of PBDD/Fs. - Abstract: The widespread use and increasing inventory of brominated flame retardants (BFRs) have caused considerable concern, as a result of BFRs emissions to the environment and of the formation of both polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) and mixed polybromochloro-dibenzo-p-dioxins and dibenzofurans (PBCDD/Fs or PXDD/Fs). Structural similarities between PBDD/Fs and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) suggest the existence of comparable formation pathways of both PBDD/Fs and PCDD/Fs, yet BFRs also act as specific precursors to form additional PBDD/Fs. Moreover, elementary bromine (Br{sub 2}) seems to facilitate chlorination by bromination of organics, followed by Br/Cl-exchange based on displacement through the more reactive halogen. Overall, PBDD/Fs form through three possible pathways: precursor formation, de novo formation, and dispersion of parts containing BFRs as impurities and surviving a fire or other events. The present review summarises the formation mechanisms of both brominated (PBDD/Fs) and mixed dioxins (PXDD/Fs with X = Br or Cl) from BFRs, recaps available emissions data of PBDD/Fs and mixed PXDD/Fs from controlled waste incineration, uncontrolled combustion sources and accidental fires, and identifies and analyses the effects of several local factors of influence, affecting the formation of PBDD/Fs and mixed PXDD/Fs during BFRs combustion.

  16. Urinary metabolites of phosphate flame retardants in workers occupied with e-waste recycling and incineration.

    Science.gov (United States)

    Yan, Xiao; Zheng, Xiaobo; Wang, Meihuan; Zheng, Jing; Xu, Rongfa; Zhuang, Xi; Lin, Ying; Ren, Mingzhong

    2018-06-01

    Urinary metabolites of phosphate flame retardants (PFRs) were determined in workers from an electronic waste (e-waste) recycling site and an incineration plant, in order to assess the PFR exposure risks of workers occupied with e-waste recycling and incineration. Bis(2-chloroethyl) phosphate (BCEP), bis(1,3-dichloro-2-propyl) phosphate (BDCIPP), and diphenyl phosphate (DPHP) were the most frequently detected chemicals (82-93%). The median concentrations of BCEP, BDCIPP, and DPHP were 1.77, 0.23, and 0.70 ng/mL, and 1.44, 0.22, and 0.11 ng/mL in samples from the e-waste site and the incineration plant, respectively. Dibutyl phosphate (DBP) was detected in all samples from the incineration plant, with a median level of 0.30 ng/mL. The concentrations of BDCIPP (r = -0.31, p waste site. Negative and significant correlations were also observed between the concentrations of BCEP (r = -0.42, p incineration plant. No gender differences were observed in levels of PFR metabolites in urine samples (p > 0.05). Concentrations of BDCIPP in female were significantly correlated with occupational exposure time (r = -0.507, p  0.05). Overall, the workers with occupational exposure to PFRs had different profiles of urinary PFR metabolites. The age, occupational exposure time, and gender seemed not to be main factors mediating the exposure to PFRs for workers occupied with e-waste recycling and incineration. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Multigenerational effects evaluation of the flame retardant tris(2-butoxyethyl) phosphate (TBOEP) using Daphnia magna.

    Science.gov (United States)

    Giraudo, Maeva; Dubé, Maxime; Lépine, Mélanie; Gagnon, Pierre; Douville, Mélanie; Houde, Magali

    2017-09-01

    Tris(2-butoxyethyl) phosphate (TBOEP) is an organophosphate ester used as substitute following the phase-out of brominated flamed retardants. Because of its high production volume and its use in a broad range of applications, this chemical is now frequently detected in the environment and biota. However, limited information is available on the long-term effects of TBOEP in aquatic organisms. In this study, Daphnia magna were exposed over three 21d generations to an environmentally relevant concentration of TBOEP (10μg/L) and effects were evaluated at the gene transcription, protein, and life-history (i.e., survival, reproduction and growth) levels. Chronic exposure to TBEOP did not impact survival or reproduction of D. magna but affected the growth output. The mean number of molts was also found to be lower in daphnids exposed to the chemical compared to control for a given generation, however there were no significant differences over the three generations. Molecular responses indicated significant differences in the transcription of genes related to growth, molting, ecdysteroid and juvenile hormone signaling, proteolysis, oxidative stress, and oxygen transport within generations. Levels of mRNA were also found to be significantly different for genes known to be involved in endocrine-mediated mechanisms such as reproduction and growth between generations F0, F1, and F2, indicating effects of parental exposure on offspring. Transcription results were supported by protein analyses with the significant decreased in catalase (CAT) activity in F1 generation, following the decreased transcription of cat in the parental generation. Taken together, these multi-biological level results suggest long-term potential endocrine disruption effects of TBOEP in D. magna exposed to an environmentally relevant concentration. This study highlights the importance of using chronic and multigenerational biological evaluation to assess risks of emerging chemicals. Crown Copyright

  18. Brominated flame retardants and perfluoroalkyl substances in sediments from the Czech aquatic ecosystem.

    Science.gov (United States)

    Hloušková, Veronika; Lanková, Darina; Kalachová, Kamila; Hrádková, Petra; Poustka, Jan; Hajšlová, Jana; Pulkrabová, Jana

    2014-02-01

    This study reports results of analysis of various groups of halogenated chemicals, including brominated flame retardants (BFRs), such as polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs), tetrabromobisphenol A (TBBPA) and perfluoroalkyl substances (PFASs) in 31 sediment samples collected in different localities of the Czech Republic. In this survey, identification of potential sources of these compounds was also performed; therefore several sampling sites located in highly industrialized areas were involved. Concentrations of target groups of analytes determined in sediments from several Czech rivers examined within this study decreased in the following order: decabromodiphenyl ether (BDE 209) > TBBPA~HBCDs~linear perfluorooctane sulfonate (L-PFOS)>other PBDEs~perfluorinated carboxylic acids (PFCAs)~perfluorooctane sulfonamide (FOSA). When compared the contamination by two monitored groups of halogenated compounds, the total content of ∑BFRs was significantly higher, i.e. in the range from the method quantification limit (MQL) to 528 μg/kg dry weight (dw) (median value 5.68 μg/kg dw), than the total concentration of ∑PFASs, that was in the range from MQL to 25.5 μg/kg dw (median value 1.48 μg/kg dw). The extremely highest content of BFR group (265-528 μg/kg dw) was found in sediments collected in sampling sites on the Labe and Lužická Nisa Rivers, which are located in highly chemical industrialized areas and also in the sample from the locality Lampertice obtained from the sedimentation tank close to the factory processing and storing waste. These concentrations were a little bit higher or comparable to those found in similar highly industrialized areas worldwide. © 2013.

  19. Presence and select determinants of organophosphate flame retardants in public swimming pools

    Energy Technology Data Exchange (ETDEWEB)

    Teo, Tiffany L.L., E-mail: tiffany.teo@unsw.edu.au [UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Kensington NSW 2052 (Australia); Coleman, Heather M., E-mail: h.coleman@ulster.ac.uk [Nanotechnology and Integrated BioEngineering Centre, School of Engineering, University of Ulster, Jordanstown, County Antrim BT37 0QB, Northern Ireland (United Kingdom); Khan, Stuart J., E-mail: s.khan@unsw.edu.au [UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Kensington NSW 2052 (Australia)

    2016-11-01

    The occurrence of five organophosphate flame retardants (PFRs) consisting of tributyl phosphate (TNBP), tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCIPP), tris(1.3-dichloro-2-propyl) phosphate (TDCIPP) and triphenyl phosphate (TPHP) in swimming pools were investigated. Fifteen chlorinated public swimming pools were sampled, including indoor pools, outdoor pools and spa pools. The analyses were carried out using isotope dilution gas chromatography tandem mass spectrometry. All five PFRs were detected in swimming pool waters with concentrations ranging from 5–27 ng/L (TNBP), 7–293 ng/L (TCEP), 62–1180 ng/L (TCIPP), 10–670 ng/L (TDCIPP) and 8–132 ng/L (TPHP). The concentrations of PFRs were generally higher in indoor swimming pools compared to outdoor swimming pools. In municipal water supplies, used to fill the swimming pools in three of the sampling locations, the five PFRs were all below the limit of quantifications, eliminating this as the source. Potential leaching of PFRs from commonly used swimming equipment, including newly purchased kickboards and swimsuits was investigated. These experiments revealed that PFRs leached from swimsuits, and may be a source of PFRs in swimming pools. A quantitative risk assessment revealed that the health risk to PFRs via swimming pools was generally low and below commonly applied health risk benchmarks. - Highlights: • TNBP, TCEP, TCIPP, TDCIPP and TPHP were detected in chlorinated swimming pools. • PFRs were below the LOQ in fill water samples collected from 3 locations. • TCIPP was observed to have the highest concentrations in swimming pools. • PFRs are leaching from swimsuits and may be a source in swimming pools. • Health risks through oral and dermal exposure to PFRs in swimming pools were low.

  20. Flame-retardant polyvinyl alcohol membrane with high transparency based on a reactive phosphorus-containing compound

    Science.gov (United States)

    Peng, Sha; Zhou, Ming; Liu, Feiyan; Zhang, Chang; Liu, Xueqing; Liu, Jiyan; Zou, Liyong; Chen, Jia

    2017-08-01

    Flame-retardant polyvinyl alcohol (PVA) membranes with high transparency and flexibility were prepared by mixing an aqueous solution of a phosphorus-containing acrylic acid (AOPA) with PVA. The reaction between AOPA and PVA, the transparency, the crystallinity and the flexibility of the membrane were investigated with Fourier transform infrared spectrometry (FTIR), UV-vis light transmittance, X-ray diffraction and tensile tests, respectively. The limited oxygen index (LOI) and vertical flame (UL 94 VTM), microscale combustion calorimetry, thermogravimetric analysis (TGA) and TGA-FTIR were employed to evaluate the flame retardancy as well as to reveal the corresponding mechanisms. Results showed that PVA containing 30 wt% of AOPA can reach the UL 94 VTM V0 rating with an LOI of 27.3% and retain 95% of the original transparency of pure PVA. Adding AOPA reduces crystallinity of PVA, while the flexibility is increased. AOPA depresses the thermal degradation of PVA and promotes char formation during combustion. The proposed decomposition mechanism indicates that AOPA acts mainly in the condensed phase.

  1. Structure–Property Studies on a New Family of Halogen Free Flame Retardants Based on Sulfenamide and Related Structures

    Directory of Open Access Journals (Sweden)

    Teija Tirri

    2016-10-01

    Full Text Available A wide variety of molecules containing S–N or S–N–S cores were synthesized, and their flame retardant properties in polypropylene (PP, low density polyethylene (LDPE and polystyrene (PS were investigated. In addition, polymers or oligomers bearing the sulfenamide functionality (SN were also synthesized. It was shown that this radical generator family based on sulfenamides is very versatile in terms of structural modifications, and the thermal decomposition range can be easily adjusted by changing the R groups attached to the core. The thermal stabilities of the different sulfenamides were examined by thermogravimetric analysis (TGA. Radicals generated by the homolytic cleavage of the S–N or S–N–S bonds at an elevated temperature can effectively interact with the intermediate products of polymer thermolysis and provide excellent flame retardant properties. The choice of most suitable SN-structure varies depending on the polymer type. For polypropylene DIN 4102-1 B2 and UL94 VTM-2 classifications were achieved with only 0.5 to 1 wt % of sulfenamide, and, in some cases, no flaming dripping was observed. Also for LDPE thin films, sulfenamides offered the DIN 4102-1 B2 rating at low dosage. In the case of polystyrene, the very stringent UL94 V-0 classification was even achieved at a loading of 5 wt % of sulfenamide.

  2. From headwaters to estuary: Distribution and fate of halogenated flame retardants (HFRs) in a river basin near the largest HFR manufacturing base in China.

    Science.gov (United States)

    Zhen, Xiaomei; Tang, Jianhui; Liu, Lin; Wang, Xinming; Li, Yanan; Xie, Zhiyong

    2018-04-15

    With the gradual phasing out of polybrominated diphenyl ethers (PBDEs), market demands for alternative halogenated flame retardants (HFRs) are increasing. The Laizhou Bay area is the biggest manufacturing base for brominated flame retardants (BFRs) in China, and the Xiaoqing River is the largest and most heavily contaminated river in this region. Water and sediment samples were collected from the headwaters to the estuary of the Xiaoqing River to investigate the distribution and fate of HFRs [i.e., PBDEs, alternative brominated flame retardants (aBFRs) and dechlorane plus (DPs). In the water samples, DPs was the most abundant flame retardant (median: 11.7ng/L), followed by decabromodiphenylethane (DBDPE) (5.92ng/L). In the sediment samples, DBDPE was the predominant flame retardant (39.5ng/g dw), followed by decabromodiphenyl ether (BDE 209) (2.81ng/g dw). The levels of DBDPE exceeded those of BDE 209 in most samples, indicating the overwhelming replacement of BDE 209 by DBDPE in this area. In the river section of this study, point source and atmospheric deposition followed by land runoff were the major factors influencing the distribution of HFRs, whereas in the estuary, riverine discharge, the estuarine maximum turbidity zone (MTZ), and hydrodynamic parameters played more important roles. Manufacturing is a significant source of contamination of the Xiaoqing River basin through atmospheric deposition and wastewater discharge. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Environmental concentration and atmospheric deposition of halogenated flame retardants in soil from Nepal: Source apportionment and soil-air partitioning.

    Science.gov (United States)

    Yadav, Ishwar Chandra; Devi, Ningombam Linthoingambi; Li, Jun; Zhang, Gan

    2018-02-01

    While various investigations have been driven on polybrominated diphenyl ethers (PBDEs) and other flame retardants (FRs) in different framework around the world, information about contamination and fate of PBDEs and other FRs in developing countries especially in the Indian subcontinent is uncommon. Nepal being located in the Indian subcontinent, very little is known about contamination level of semi-volatile organic pollutants discharged into the environment. This motivated us to investigate the environmental fate of halogenated flame retardant (HFRs) in Nepalese condition. In this study, we investigated the concentration, fate, and sources of 9 PBDEs, 2 dechlorane plus isomers (DPs), and 6 novel brominated flame retardants (NBFRs). Moreover, air-soil exchange and soil-air partitioning were also evaluated to characterize the pattern of air-soil exchange and environmental fate. In general, the concentrations of NBFRs in soil were more prevalent than PBDEs and DPs, and accounted 95% of ∑HFRs. By and large, the concentrations of NBFRs and DPs were measured high in Kathmandu, while PBDEs level exceeded in Pokhara. Principal component analysis (PCA) study suggested contributions from commercial penta-, octa-, and deca-BDEs products and de-bromination of highly brominated PBDEs as the significant source of PBDEs. Likewise, low f anti ratio suggested DPs in soil might have originated from long-range atmospheric transport from remote areas, while high levels of decabromodiphenyl ethane (DBDPE) in soil were linked with the use of wide varieties of consumer products. The estimated fugacity fraction (ff) for individual HFR was quite lower (soil is overwhelming. Soil-air partitioning study revealed neither octanol-air partition coefficient (K OA ) nor black carbon partition coefficient (K BC-A ) is an appropriate surrogate for soil organic matter (SOM), subsequently, absorption by SOM has no or little role in the partitioning of HFRs. Copyright © 2017 Elsevier Ltd. All

  4. Exposure assessment of organophosphorus and organobromine flame retardants via indoor dust from elementary schools and domestic houses.

    Science.gov (United States)

    Mizouchi, Shigekazu; Ichiba, Masayoshi; Takigami, Hidetaka; Kajiwara, Natsuko; Takamuku, Toshiyuki; Miyajima, Toru; Kodama, Hiroki; Someya, Takashi; Ueno, Daisuke

    2015-03-01

    To assess the exposure of flame retardants (FRs) for school-children, organophosphorus flame retardants and plasticizers (PFRs) and organobromine flame retardants (BFRs) were determined in the indoor dust samples collected from elementary schools and domestic houses in Japan in 2009 and 2010. PFRs were detected in all the dust samples analyzed and the highest concentration of total PFRs was thousand-fold higher than that of BFRs. Among the PFRs, tris(butoxyethyl)phosphate (TBOEP) showed the highest concentration with a median (med.) of 270,000 ng g(-1) dry weight (3700-5,500,000 ng g(-1) dry weight), followed by tris(methylphenyl)phosphate (TMPPs)>triphenyl phosphate (TPHP)=tris(1,3-dichloro-2-propyl)phosphate (TDCIPP)=tris(2-chloroisopropyl)phosphate (TCIPP)=tris(2chloroethyl)phosphate (TCEP)>ethylhexyl diphenyl phosphate (EHDPP). Significantly higher concentrations of TBOEP, tri-n-butyl phosphate (TNBP), TPHP, TMPPs, and total-PFRs were found in dust samples from elementary schools than from domestic houses. It might be due to that higher concentrations of TBOEP (as leveling agent) were detected from the floor polisher/wax products collected in those elementary schools. On the other hand, significantly higher concentrations of TCEP, TCIPPs, and total chloroalkyl-PFRs were found in domestic houses than in elementary schools. Exposure assessments of PFRs via indoor dust from elementary schools and domestic houses were conducted by calculating the hazard quotient (HQ). Among PFRs, HQs for TBOEP exceeded 1 (higher than reference dose: RfD) and its highest value was 1.9. To reduce the intake of TBOEP by school-children, it is recommended that the use of floor polisher/wax containing TBOEP be reduced in schools. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Preparation and characterization of flame retardant n-hexadecane/silicon dioxide composites as thermal energy storage materials.

    Science.gov (United States)

    Fang, Guiyin; Li, Hui; Chen, Zhi; Liu, Xu

    2010-09-15

    Flame retardant n-hexadecane/silicon dioxide (SiO(2)) composites as thermal energy storage materials were prepared using sol-gel methods. In the composites, n-hexadecane was used as the phase change material for thermal energy storage, and SiO(2) acted as the supporting material that is fire resistant. In order to further improve flame retardant property of the composites, the expanded graphite (EG) was added in the composites. Fourier transformation infrared spectroscope (FT-IR), X-ray diffractometer (XRD) and scanning electronic microscope (SEM) were used to determine chemical structure, crystalloid phase and microstructure of flame retardant n-hexadecane/SiO(2) composites, respectively. The thermal properties and thermal stability were investigated by a differential scanning calorimeter (DSC) and a thermogravimetric analysis apparatus (TGA), respectively. The SEM results showed that the n-hexadecane was well dispersed in the porous network of the SiO(2). The DSC results indicated that the melting and solidifying latent heats of the composites are 147.58 and 145.10 kJ/kg when the mass percentage of the n-hexadecane in the composites is 73.3%. The TGA results showed that the loading of the EG increased the charred residue amount of the composites at 700 degrees C, contributing to the improved thermal stability of the composites. It was observed from SEM photographs that the homogeneous and compact charred residue structure after combustion improved the flammability of the composites. Copyright 2010 Elsevier B.V. All rights reserved.

  6. Comparisons of indoor active and passive air sampling methods for emerging and legacy halogenated flame retardants in Beijing, China offices

    OpenAIRE

    Seth Newton; Ulla Sellström; Stuart Harrad; Gang Yu; Cynthia A. de Wit

    2016-01-01

    One active and two passive air sampling configurations were deployed simultaneously in three offices in Beijing, China to test their comparability for sampling emerging and legacy halogenated flame retardants spanning a large range of octanol–air partition coefficients (KOA). Sampling in each office was carried out for three consecutive 28-day periods in the spring-summer of 2013. The active sampler was run for 2.5 h at different times every day for 28 days to parallel the passive samplers an...

  7. Emerging halogenated flame retardants and hexabromocyclododecanes in food samples from an e-waste processing area in Vietnam.

    Science.gov (United States)

    Tao, Fang; Matsukami, Hidenori; Suzuki, Go; Tue, Nguyen Minh; Viet, Pham Hung; Takigami, Hidetaka; Harrad, Stuart

    2016-03-01

    This study reports concentrations of selected emerging halogenated flame retardants (HFRs) and hexabromocyclododecanes (HBCDs) in foodstuffs sourced from an e-waste processing area in Vietnam and two reference sites in Vietnam and Japan. Concentrations of all target HFRs in e-waste-impacted samples in this study exceed significantly (p e-waste processing activities exert a substantial impact on local environmental contamination and human dietary exposure. Significant linear positive correlations in concentrations of syn-Dechlorane Plus (DP) and anti-DP were found between soils and those in co-located chicken samples (p e-waste processing sites and non-e-waste processing areas elsewhere.

  8. Occurrence of emerging flame retardants from e-waste recycling activities in the northern part of Vietnam

    OpenAIRE

    Someya, Masayuki; Suzuki, Go; Ionas, Alin C.; Tue, Nguyen Minh; Xu, Fuchao; Matsukami, Hidenori; Covaci, Adrian; Tuyen, Le Huu; Viet, Pham Hung; Takahashi, Shin; Tanabe, Shinsuke; Takigami, Hidetaka

    2016-01-01

    This study investigated the contamination status of 21 emerging flame retardants (FRs) in soils (n = 32) and river sediments (n = 8) from an e-waste recycling (EWR) site in the northern part of Vietnam. Among analyzed FRs, higher levels of decabromodiphenyl ethane (DBDPE) (ND–4200 ng/g dw), 1,2-bis-(2,4,6-tribromophenoxy)ethane (BTBPE) (ND–350 ng/g dw) and Dechlorane Plus isomers (DPs) (ND–65 ng/g dw) were found in soils near EWR workshops and open burning places. The highest concentrations o...

  9. The novel silicon-containing epoxy/PEPA phosphate flame retardant for transparent intumescent fire resistant coating

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Yanchao [School of Materials Science and Engineering, Tongji University, 4800 Cao' an Road, Shanghai 201804 (China); Wang, Guojian, E-mail: wanggj@tongji.edu.cn [School of Materials Science and Engineering, Tongji University, 4800 Cao' an Road, Shanghai 201804 (China); Key Laboratory of Advanced Civil Engineering Materials, Ministry of Education, 4800 Cao' an Road, Shanghai 201804 (China)

    2016-11-01

    Highlights: • The novel halogen-free flame retardant containing silicon and caged bicyclic phosphate was synthesized. • A novel transparent intumescent fire resistant coating was developed by the P-Si synergistic flame retardant and melamine formaldehyde resin. • Excellent fire protection of the transparent intumescent fire resistant coating. • The P-Si synergistic flame retardant could improve the thermo-oxidation resistance of transparent fire resistant coating. - Abstract: A series of novel silicon-containing epoxy/PEPA phosphate flame retardants (EPPSi) were synthesized by polyphosphoric acid (PPA), caged bicyclic phosphate 1-oxo-4-hydroxymethyl-2,6,7-trioxa-L-phosphabicyclo [2.2.2] octane (PEPA), and different ratios of silicon-containing epoxy 1,1,3,3-tetramethyl-1,3-bis(3-(oxiran-2-ylmethoxy)propyl)disiloxane (TMSEP) to 1,4-butanediol diglycidyl ether (BDE). The chemical structure of EPPSi was confirmed by Fourier transform infrared spectroscopy (FTIR) and {sup 1}H nuclear magnetic resonance spectroscopy ({sup 1}H NMR). Afterwards, the transparent intumescent fire resistant coatings were prepared by mixing EPPSi and melamine formaldehyde resin. The influence of silicon on the fire protection of coatings was intensively investigated by fire protection test, intumescence ratio, scanning electron microscope (SEM), compressive strength test, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA) and real-time FTIR. It was found that the fire resistant coatings obtained the best fire protection when the ratio of TMESP/BDE was 20/100, while excessive TMSEP made the fire protection of coatings deceased sharply. The intumescence ratio, compressive strength test and SEM result showed that a synergistic effect existed between phosphorus and silicon, which improved the foam structure and compressive strength of the char layer significantly. XPS result proved the out-migration effect of silicon. The high concentration silicon on surface played

  10. Improvement of thermal properties and flame retardancy of epoxy-amine thermosets by introducing bisphenol containing azomethine moiety

    Directory of Open Access Journals (Sweden)

    2007-05-01

    Full Text Available A novel bisphenol 1, 4'-bis{4-[(4-hydroxy phenyliminomethylidene] phenoxy} benzene (BHPB, which contains azomethine moiety and flexible aromatic ether linkage, was synthesized and introduced into the curing system composed of diglycidyl ether of bisphenol A (DGEBA and diamine. The curing behavior of DGEBA/diamine changed dramatically due to the introduction of BHPB. The resultant epoxy thermosets containing BHPB had high Tgs (127-160 °C, high Td, 5% (>=330°C and high integral procedure decomposition temperature (IPDT values (662-1230°C and good flame retardancy for their high Limited Oxygen Index (LOI values (above 29.5.

  11. Human Indoor Exposure to Airborne Halogenated Flame Retardants: Influence of Airborne Particle Size.

    Science.gov (United States)

    La Guardia, Mark J; Schreder, Erika D; Uding, Nancy; Hale, Robert C

    2017-05-09

    Inhalation of halogenated flame-retardants (HFRs) released from consumer products is an important route of exposure. However, not all airborne HFRs are respirable, and thus interact with vascular membranes within the gas exchange (alveolar) region of the lung. HFRs associated with large (>4 µm), inhalable airborne particulates are trapped on the mucosal lining of the respiratory tract and then are expelled or swallowed. The latter may contribute to internal exposure via desorption from particles in the digestive tract. Exposures may also be underestimated if personal activities that re-suspend particles into the breathing zone are not taken into account. Here, samples were collected using personal air samplers, clipped to the participants' shirt collars (n = 18). We observed that the larger, inhalable air particulates carried the bulk (>92%) of HFRs. HFRs detected included those removed from commerce (i.e., polybrominated diphenyl ethers (Penta-BDEs: BDE-47, -85, -100, -99, and -153)), their replacements; e.g., 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (TBB or EH-TBB); bis(2-ethylhexyl) 3,4,5,6-tetrabromophthalate (TBPH or BEH-TEBP) and long-produced chlorinated organophosphate-FRs (ClOPFRs): tris(2-chloroethyl)phosphate (TCEP), tris(1-chloro-2-propyl)phosphate (TCPP or TCIPP), and tris(1,3-dichloro-2-propyl)phosphate (TDCPP or TDCIPP). Our findings suggest estimates relying on a single exposure route, i.e., alveolar gas exchange, may not accurately estimate HFR internal dosage, as they ignore contributions from larger inhalable particulates that enter the digestive tract. Consideration of the fate and bioavailability of these larger particulates resulted in higher dosage estimates for HFRs with log K oa 12 (i.e., TBB and TBPH) compared to the alveolar route exposure alone. Of those HFRs examined, the most significant effect was the lower estimate by 41% for TBPH. The bulk of TBPH uptake from inhaled particles was estimated to be through the digestive tract, with

  12. Associations between flame retardant applications in furniture foam, house dust levels, and residents' serum levels.

    Science.gov (United States)

    Hammel, Stephanie C; Hoffman, Kate; Lorenzo, Amelia M; Chen, Albert; Phillips, Allison L; Butt, Craig M; Sosa, Julie Ann; Webster, Thomas F; Stapleton, Heather M

    2017-10-01

    Polyurethane foam (PUF) in upholstered furniture frequently is treated with flame retardant chemicals (FRs) to reduce its flammability and adhere to rigorous flammability standards. For decades, a commercial mixture of polybrominated diphenyl ethers (PBDEs) called PentaBDE was commonly applied to foam to fulfill these regulations; however, concerns over toxicity, bioaccumulation, and persistence led to a global phase-out in the mid-2000s. Although PentaBDE is still detected in older furniture, other FR compounds such as tris(1,3-dichloroisopropyl) phosphate (TDCIPP) and Firemaster® 550 (FM550) have been increasingly used as replacements. While biomonitoring studies suggest exposure is widespread, the primary sources of exposure are not clearly known. Here, we investigated the relationships between specific FR applications in furniture foam and human exposure. Paired samples of furniture foam, house dust and serum samples were collected from a cohort in North Carolina, USA and analyzed for FRs typically used in PUF. In general, the presence of a specific FR in the sofa of a home was associated with an increase in the concentration of that FR in house dust. For example, the presence of PentaBDE in sofas was associated with significantly higher levels of BDE-47, a major component of PentaBDE, in house dust (10 β =6.4, p<0.001). A similar association was observed with a component of FM550, 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB), with levels that were approximately 3 times higher in house dust when FM550 was identified in the sofa foam (p<0.01). These relationships were modified by dust loading rates in the living room and the ratio of sofa size to room size. Interestingly, levels of TDCIPP and tris(1-chloro-2-isopropyl) phosphate (TCIPP) were also higher in dust with detections in sofa foam; however, these associations were not statistically significant and may suggest there are other prominent sources of these compounds in the home. In addition, the

  13. The distribution and accumulation of phosphate flame retardants (PFRs) in water environment.

    Science.gov (United States)

    Zhang, Ying; Zheng, Xiaobo; Wei, Lifei; Sun, Runxia; Guo, Huiying; Liu, Xinyu; Liu, Shengyu; Li, Yi; Mai, Bixian

    2018-02-21

    Phosphate flame retardants (PFRs) were measured in surface water (n=11), suspended particle matter (SPM, n=11), sediment (n=11), and fish samples (n=26) from the Pearl River Delta located in South China. Triethyl phosphate (TEP), tri(2-chloroethyl) phosphate (TCEP), tris(chloroisopropyl) phosphate (TCIPP), tri-n-butyl phosphate (TNBP), triphenyl phosphate (TPHP), and tricresyl phosphate (TMPP) were detected in more than half of surface water, SPM, and sediment samples. The median ΣPFR levels were 837ng/L, 54.6ng/g dry weight (dw), and 37.1ng/g dw in surface water, SPM, and sediment samples, respectively. No significant correlations were found between the concentrations of most PFRs and organic carbon contents in SPM and sediment (p>0.05). In surface water samples, tris(2-butoxyethyl) phosphate (TBOEP, 27% of ΣPFRs) and TEP (23% of ΣPFRs) were the predominant chemicals, while TNBP (38% of ΣPFRs) and TCEP (32% of ΣPFRs) dominated in ΣPFRs in SPM samples, and TCEP (48% of ΣPFRs) and TCIPP (25% of ΣPFRs) dominated in ΣPFRs in sediment samples. The proportions of phenyl-PFRs and chlorinated-PFRs in ΣPFRs increased from surface water to SPM and sediment. The distribution ratios of PFRs between water and organic carbon in SPM (or observed K OC ) were generally 2-3 orders of magnitude higher than the predicted K OC . TNBP (nd-2.42ng/g wet weight (ww)), TCEP (nd-4.96ng/g ww), and TCIPP (nd-2.42ng/g ww) were detected in 27%, 35%, and 23% of all fish samples, respectively. The log bioaccumulation factors (BAFs) ranged 2.56-2.78, 2.15-3.11, and 2.61-3.10 for TNBP, TCEP, and TCIPP, respectively. The biota-sediment accumulation factors (BSAFs) of TNBP, TCEP, and TCIPP were generally lower than 1 except for the BSAF of TCIPP in common carp. The results indicate the species-specific bioaccumulation of PFRs in fish species. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Brominated flame retardants in the Arctic. An overview of spatial and temporal trends

    Energy Technology Data Exchange (ETDEWEB)

    Wit, C. de [Institute of Applied Environmental Research, Stockholm (Sweden); Alaee, M.; Muir, D. [National Water Research Institute, Burlington, MA (United States)

    2004-09-15

    The Stockholm Convention on Persistent Organic Pollutants (POPs), which entered into force on May 17, 2004, includes wording that chemicals with the characteristics of POPs are those found in locations ''distant from sources'' and those for which ''monitoring data showing that long-range environmental transport of the chemical may have occurred''. Thus, the Arctic has become an important indicator region for assessment of persistence and bioaccumulation. The Arctic environment is well suited as a region in which to evaluate POPs. Some regions of thee Arctic, particularly the Barents Sea area north of Norway and western Russia are relatively close to source regions of POPs. Cold conditions favor persistence of POPs relative to temperate or tropical environments. The presence of fourth level carnivores (e.g. polar bears and seabirds), and storage of lipid as an energy source, make Arctic food webs vulnerable to bioaccumulative chemicals. Indigenous people in the Arctic utilizing a traditional diet, which is high in nutritionally beneficial fat, results in their elevated exposure to some POPs. The first indication that brominated flame retardants (BFRs) were reaching the Arctic was the detection by Jansson et al. of lower molecular weight polybrominated diphenyl ethers (PBDEs) in Svalbard Brunnichfs guillemots (130 ng/g lipid weight) and ringed seals (40 ng/g lw) collected in 1981. Whitefish collected from Lake Storvindeln in 1986, a pristine mountain lake in the Swedish mountains near Ammarnas, had {sigma}PBDE levels of 26 ng/g lw. Despite these early findings, only recently have the spatial and temporal trends of BFRs been studied in detail in the Arctic. The purpose of this paper is to review the new data on BFRs in the Arctic and assess whether this information supports the view that PBDEs and other BFRs of similar molecular weight are POPs and potential global pollutants. This review is based on a recent assessment of POPs

  15. Organophosphorus flame retardants and heavy metals in municipal landfill leachate treatment system in Guangzhou, China.

    Science.gov (United States)

    Deng, Mingjun; Kuo, Dave T F; Wu, Qihang; Zhang, Ying; Liu, Xinyu; Liu, Shengyu; Hu, Xiaodong; Mai, Bixian; Liu, Zhineng; Zhang, Haozhi

    2018-05-01

    The occurrence, distribution and removal efficiencies of organophosphorus flame retardants (OPFRs) and metals were examined in a municipal landfill leachate treatment system in Guangzhou, China. Five OPFRs and thirty-five metals were detected in wastewater samples collected at different treatment stages. ∑OPFRs was reduced from 4807.02 ng L -1 to 103.91 ng L -1 through the treatment system, with close to 98% removed from the dissolved phase. Tris(clorisopropyl) phosphates (TCPPs) dominated through the treatment process and accounted for over 80% and 50% of ∑OPFRs at the influent and the effluent, respectively. TCPPs were most efficiently removed (98.6%) followed by tris(2-chloroethyl) phosphate (TCEP) (96.6%) and triphenyl phosphate (TPP) (88.5%). For metals, Fe, Cr, and Rb were dominant in the raw leachate, detected at 7.55, 2.82, and 4.50 mg L -1 , respectively. Thirteen regulated heavy metals - including eight major pollutants (i.e., As. Cd, Cr, Cu, Hg, Ni, Pb, and Zn) - have been detected in all wastewater samples at sub-mg L -1 levels. Over 99.5% removal was achieved for Cr, Ni, and Fe, and close to 95% removal efficiency was observed for Rb. For the eight major heavy metals, over 99% removal was observed; the only exception was Cu, which was removed at 89%. It was found that microfiltration/reverse osmosis was critical for the removal of OPFRs and heavy metals while the core biological treatment played a minor role towards their removal. Remobilization of Co, Cu, Fe, Hg, Mn, Ni, Sb, and Sr from the returned sludge occurred during the second denitrification, indicating the need for additional post-biological process for effective removal of both contaminants. This study highlights the critical need to develop cheap, effective treatment technologies for contaminants-laden leachate generated from open dumps and under-designed landfills. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Flame-retardant electrical conductive nanopolymers based on bisphenol F epoxy resin reinforced with nano polyanilines.

    Science.gov (United States)

    Zhang, Xi; He, Qingliang; Gu, Hongbo; Colorado, Henry A; Wei, Suying; Guo, Zhanhu

    2013-02-01

    Both fibril and spherical polyaniline (PANI) nanostructures have successfully served as nanofillers for obtaining epoxy resin polymer nanocomposites (PNCs). The effects of nanofiller morphology and loading level on the mechanical properties, rheological behaviors, thermal stability, flame retardancy, electrical conductivity, and dielectric properties were systematically studied. The introduction of the PANI nanofillers was found to reduce the heat-release rate and to increase the char residue of epoxy resin. A reduced viscosity was observed in both types of PANI-epoxy resin liquid nanosuspension samples at lower loadings (1.0 wt % for PANI nanospheres; 1.0 and 3.0 wt % for PANI nanofibers), the viscosity was increased with further increases in the PANI loading for both morphologies. The dynamic storage and loss modulii were studied, together with the glass-transition temperature (T(g)) being obtained from the peak of tan δ. The critical PANI nanofiller loading for the modulus and T(g) was different, i.e., 1.0 wt % for the nanofibers and 5.0 wt % for the nanospheres. The percolation thresholds of the PANI nanostructures were identified with the dynamic mechanical property and electrical conductivity, and, because of the higher aspect ratio, nanofibers reached the percolation threshold at a lower loading (3.0 wt %) than the PANI nanospheres (5.0 wt %). The PANI nanofillers could increase the electrical conductivity, and, at the same loading, the epoxy nanocomposites with the PANI nanofibers showed lower volume resistivity than the nanocomposites with the PANI nanospheres, which were discussed with the contact resistance and percolation threshold. The tensile test indicated an improved tensile strength of the epoxy matrix with the introduction of the PANI nanospheres at a lower loading (1.0 wt %). Compared with pure epoxy, the elasticity modulus was increased for all the PNC samples. Moreover, further studies on the fracture surface revealed an enhanced

  17. Urinary metabolites of organophosphate flame retardants and their variability in pregnant women.

    Science.gov (United States)

    Hoffman, Kate; Daniels, Julie L; Stapleton, Heather M

    2014-02-01

    Organophosphate flame retardants (OPFRs) are commonly added to consumer products to reduce their flammability. Based on levels of OPFRs in indoor environments, human exposure is likely chronic and ubiquitous. Animal studies suggest that exposure to some OPFRs may result in adverse health impacts, particularly for Tris (1,3-dichloropropyl) phosphate (TDCPP); however, human data on the impacts of exposure to OPFRs are lacking. To design human studies, more information is needed on the stability of measured OPFRs in human samples over time. In this study, we sought to assess the degree of temporal variability of urinary TDCPP and triphenyl phosphate (TPP) metabolites throughout pregnancy in a cohort of women from central North Carolina. Eight pregnant women provided multiple urine samples: 3 during the 18th week of pregnancy, 1 during the 28th week, and 1 shortly after the child's birth. Bis (1,3-dichloropropyl) phosphate (BDCPP) and diphenyl phosphate (DPP), the respective metabolites of TDCPP and TPP, were measured in urine samples using liquid chromatography-tandem mass spectrometry. BDCPP and DPP were each detected in 38 of 39 urine samples and were not normally distributed. Geometric mean BDCPP and DPP concentrations were 1.3ng/mL (interquartile range (IQR): 0.8, 2.7ng/mL) and 1.9ng/mL (IQR: 0.9, 3.5ng/mL), respectively. BDCPP and DPP were moderately to strongly reliable over one week (intraclass correlation coefficient (ICC)=0.5; 95% confidence interval (CI): 0.4, 0.7 and ICC=0.7; 95% CI: 0.5, 0.8, respectively), and over the entire pregnancy (ICC=0.5 95% CI: 0.3, 0.7 and ICC=0.6; 95% CI: 0.4, 0.7, respectively). These data suggest that exposures to TDCPP and TPP are widespread and variable for pregnant women, and that a single measure of BDCPP or DPP, taken in the second trimester, likely captures information on the rank order of exposure throughout pregnancy. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Brominated flame retardants in the Arctic environment--trends and new candidates.

    Science.gov (United States)

    de Wit, Cynthia A; Herzke, Dorte; Vorkamp, Katrin

    2010-07-01

    Polybrominated diphenyl ethers (PBDEs) containing two to 10 bromines are ubiquitous in the Arctic, in both abiotic and biotic samples. Hexabromocyclododecane (HBCD) is also ubiquitous in the Arctic, with the gamma-HBCD isomer predominating in air, the alpha-HBCD isomer predominating in biota and similar concentrations of alpha-, beta- and gamma-HBCD found in marine sediments. Other brominated flame retardants (BFRs) found in some Arctic samples are polybrominated biphenyls (PBBs), tetrabromobisphenol A (TBBPA), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), hexabromobenzene (HxBBz), pentabromoethylbenzene (PBEB), pentabromotoluene (PBT), and 1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane (TBECH). Temporal trends of tetra- to heptaBDEs and HBCD show increasing concentrations or a tendency to levelling off depending on the matrix (air, sediment, biota) and location, but no uniform picture for the Arctic emerges. BDE-209 concentrations are increasing in air. PBDEs and HBCD spatial trends in seabirds and marine mammals are similar to those seen previously for polychlorinated biphenyls (PCBs), with highest concentrations found in organisms from East Greenland and Svalbard. These trends indicate western Europe and eastern North America as important source regions of these compounds via long range atmospheric transport and ocean currents. Latitudinal trends showed lower concentrations and fluxes of PBDEs at higher latitudes. The tetra-hexaBDEs and alpha-HBCD biomagnify in Arctic food webs. Results for BDE-209 are more conflicting, showing either only low or no biomagnification potential. PBDE and HBCD concentrations are lower in terrestrial organisms and higher in marine top predators such as some killer whale populations in Alaska and glaucous gulls from the Barents Sea area. Higher concentrations are seen near populated areas indicating local sources. Findings of BTBPE, HxBBz, PBEB, PBT and TBECH in seabirds and/or marine mammals indicate that these compounds reach the

  19. A effective flame retardant for epoxy resins based on poly(DOPO substituted dihydroxyl phenyl pentaerythritol diphosphonate)

    International Nuclear Information System (INIS)

    Wang Xin; Song Lei; Xing Weiyi; Lu Hongdian; Hu Yuan

    2011-01-01

    Poly(DOPO substituted dihydroxyl phenyl pentaerythritol diphosphonate) (PFR) was synthesized via the reaction between 10-(2,5-dihydroxyl-phenyl)-9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO-BQ) and pentaerythritol diphosphonate dichloride (SPDPC). The structures of PFR were characterized by Fourier transformed infrared (FTIR) spectroscopy and 1 H nuclear magnetic resonance ( 1 H NMR). Thermal degradation behaviors and flame retardant properties of the epoxy resin (ER)/PFR systems were investigated from the thermogravimetric analysis (TGA), UL-94 test and the limiting oxygen index (LOI) test. Moreover, the surface morphology of the char residue was studied by scanning electron microscopy (SEM). When the PFR content reached 10 wt%, the epoxy resin system met the UL-94 V0 classification and the LOI value of 30.2. The microscale combustion calorimetry (MCC) was used to evaluate the combustion behaviors of the ER/PFR. It was found that the addition of PFR obviously decreased the value of peak heat release rate and total heat release of the hybrids. The TGA results showed that the epoxy resin with 10 wt% PFR exhibited high char yields. The high char yields and the high limiting oxygen index values were found to certify the excellent flame retardancy of this phosphorus-containing epoxy resin.

  20. Plant selective uptake of halogenated flame retardants at an e-waste recycling site in southern China.

    Science.gov (United States)

    Wang, Shaorui; Wang, Yan; Luo, Chunling; Li, Jun; Yin, Hua; Zhang, Gan

    2016-07-01

    The concentrations and homolog patterns of halogenated flame retardants (HFRs) in vegetables grown at an e-waste contaminated site were investigated. Polybrominated diphenyl ethers (PBDEs) were the dominant HFRs in vegetable tissues, with concentrations ranging from 10.3 to 164 ng g(-1) and 1.16-107 ng g(-1) in shoots and roots, respectively, followed by novel brominated flame retardants (NBFRs) and dechlorane plus (DPs). This is an indication that PBDE contamination in vegetables grown around e-waste recycling sites may pose a risk to the local terrestrial ecosystem and residents. In addition, this is the first report on the concentrations and compositions of NBFRs in vegetables around e-waste recycling sites. The HFRs concentrations in vegetables varied greatly with the vegetable species, with the highest concentrations observed in Brassica oleracea var. capitata. Root concentration factors (RCF) decreased with increasing log Kow of HFRs, which indicated that the uptake of HFRs was controlled mainly by log Kow. Dissimilar HFRs profiles in shoots and roots suggested that the uptake and translocation of HFRs by plants were selective, with lower halogenated congeners prone to accumulation in vegetable tissues. Positive relationships between PBDEs and their substitutes were observed in vegetable tissues, suggesting that the replacement of PBDEs by NBFRs has not resulted in an obvious transition in plants within the study area. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Comparisons of indoor active and passive air sampling methods for emerging and legacy halogenated flame retardants in Beijing, China offices

    Directory of Open Access Journals (Sweden)

    Seth Newton

    2016-06-01

    Full Text Available One active and two passive air sampling configurations were deployed simultaneously in three offices in Beijing, China to test their comparability for sampling emerging and legacy halogenated flame retardants spanning a large range of octanol–air partition coefficients (KOA. Sampling in each office was carried out for three consecutive 28-day periods in the spring-summer of 2013. The active sampler was run for 2.5 h at different times every day for 28 days to parallel the passive samplers and sample a total volume comparable to that sampled by the passive samplers (∼20 m3. At the end of each 28-day sampling period, a separate active air sample was taken by running the sampler pump continuously for about 2.5 days. The comparability of measured concentrations varied between the air sampling configurations and for different compounds. The predominant compound measured in nearly all samples was BDE-209, a compound known to have heavy use in China. Several emerging flame retardants were also detected including DBE-DBCH, PBT, HBB, DDC-CO, and DBDPE. Very little of the tetra-hexabrominated BDEs associated with the technical PentaBDE product was observed.

  2. Halogenated flame retardants during egg formation and chicken embryo development: maternal transfer, possible biotransformation, and tissue distribution.

    Science.gov (United States)

    Zheng, Xiao-Bo; Luo, Xiao-Jun; Zeng, Yan-Hong; Wu, Jiang-Ping; Chen, She-Jun; Mai, Bi-Xian

    2014-08-01

    Hen muscle, eggs, and newborn chick tissues (muscle and liver) were collected from an electronic waste recycling site in southern China. The authors examined the maternal transfer, potential metabolism, and tissue distribution of several halogenated flame retardants (HFRs) during egg formation and chicken embryo development. The pollutant composition changes significantly from hen muscle to eggs and from eggs to tissues of newborn chicks. Higher-halogenated chemicals, such as octa- to deca-polybrominated diphenyl ether (PBDE) congeners, deca-polybrominated biphenyl (PBB209), and dechlorane plus (DP), are less readily transferred to eggs compared with lower-halogenated chemicals. During embryo development, PBDEs are the most likely to be metabolized, whereas decabromodiphenyl ethane (DBDPE) is the least. The authors also observed selective maternal transfer of anti-DP and stereoselective metabolism of syn-DP during chicken embryo development. During tissue development, liver has greater affinity than the muscle for chemcials with a high log octanol-water partition coefficient, with the exception of DBDPE. The differences in metabolism potential of different chemicals in chicken embryos cause pollutant composition alterations. Halogenated flame retardant from maternal transfer and tissue distribution also exhibited chemical specificity, especially for DBDPE. Levels of DBDPE were elevated along with the full process from hen muscle to eggs and from eggs to chick tissues. More attention should be paid to the selective accumulation and biotransformation of HFRs in the early development stage of birds. © 2014 SETAC.

  3. Free radical induced grafting of acrylonitrile on pre-treated rice straw for enhancing its durability and flame retardancy

    Directory of Open Access Journals (Sweden)

    Aparna Mukherjee

    2017-01-01

    Full Text Available The present investigation highlights the feasibility of a polymer grafting process to enhance the durability and flame retardancy of rice straw towards application as a low cost roofing material. The success of this grafting methodology was perceived to depend upon a bi-step pre-treatment process encompassing delignification and inorganic salts dispersion. Subsequently free radical polymer grafting of acrylonitrile onto rice straw was implemented by immersion mechanism initiated by oxalic acid-potassium permanganate initiator. The percentage of grafting, limiting oxygen index (LOI, biodegradability of the grafted rice straw and grafting yield percentage was estimated to be 57%, 27%, 0.02% and 136.67%, respectively. The weight loss of polymer grafted rice straw implied its less biodegradability over raw straw. Thus, the process of grafting contrived in the present analysis can be a promising and reliable technique for the efficient utilization of rice straw as an inexpensive roofing element through the augmentation of its durability and flame retardancy.

  4. Removal of pharmaceuticals, polybrominated flame retardants and UV-filters from sludge by the fungus Trametes versicolor in bioslurry reactor

    International Nuclear Information System (INIS)

    Rodríguez-Rodríguez, Carlos E.; Barón, Enrique; Gago-Ferrero, Pablo; Jelić, Aleksandra; Llorca, Marta; Farré, Marinella; Díaz-Cruz, M. Silvia; Eljarrat, Ethel; Petrović, Mira; Caminal, Glòria; Barceló, Damià

    2012-01-01

    Highlights: ► Sludge from a WWTP was treated in a fungal slurry reactor with Trametes versicolor. ► Twenty-four pharmaceuticals were removed at important extents. ► UV-filters and brominated flame retardants were also degraded. ► Overall toxicity of sludge increased despite the pollutant removal. - Abstract: Conventional wastewater treatments are inefficient in the removal of many organic pollutants. The presence of these contaminants in the final sludge represents a source of environmental pollution due to the increasing use of biosolids in land application. A biotechnological approach which employed the fungus Trametes versicolor in a sludge-bioslurry reactor was assessed in order to remove several groups of emerging pollutants. Biological fungal activity was monitored by means of ergosterol and laccase determinations. Fifteen out of 24 detected pharmaceuticals were removed at efficiencies over 50% after the treatment, including eight completely degraded. Removal ranged between 16–53% and 22–100% for the brominated flame retardants and the UV-filters, respectively. Only two of all the detected compounds remained unchanged after the treatment. Although elimination results are promising, the toxicity of the final sludge increased after the treatment. This finding is contrary to the toxicity results obtained in similar treatments of sludge with T. versicolor in solid-phase.

  5. Occurrence of alternative flame retardants in indoor dust from New Zealand: indoor sources and human exposure assessment.

    Science.gov (United States)

    Ali, Nadeem; Dirtu, Alin C; Van den Eede, Nele; Goosey, Emma; Harrad, Stuart; Neels, Hugo; 't Mannetje, Andrea; Coakley, Jonathan; Douwes, Jeroen; Covaci, Adrian

    2012-09-01

    Due to worldwide restrictions on polybrominated diphenyl ethers (PBDEs), the demand for alternative flame retardants (AFRs), such as organophosphate flame retardants (OPFRs), novel brominated FRs (NBFRs) and hexabromocyclododecanes (HBCDs), has recently increased. Little is known about human exposure to NBFRs and OPFRs and that their levels in dust have been scarcely evaluated worldwide. To increase the knowledge regarding these chemicals, we measured concentrations of five major NBFRs, ten OPFRs and three HBCD isomers in indoor dust from New Zealand homes. Dust samples were taken from living room floors (n=34) and from mattresses of the same houses (n=16). Concentrations (ngg(-1)) of NBFRs were: 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) (TDCPP) (20-16560), tri-phenyl-phosphate (TPhP) (20-35190), and tri-cresyl-phosphate (TCP) (<50-3760). HBCD concentrations fell in the range <2-4100ngg(-1). BTBPE, DBDPE, TBPH, TBEP, and TnBP showed significant positive correlation (p<0.05) between their concentrations in mattresses and the corresponding floor dust (n=16). These data were used to derive a range of plausible exposure scenarios. Although the estimated exposure is well below the corresponding reference doses (RfDs), caution is needed given the likely future increase in use of these FRs and the currently unknown contribution to human exposure by other pathways such as inhalation and diet. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Preparation, Characterization, Thermal, and Flame-Retardant Properties of Green Silicon-Containing Epoxy/Functionalized Graphene Nanosheets Composites

    Directory of Open Access Journals (Sweden)

    Ming-Yuan Shen

    2013-01-01

    Full Text Available In this investigation, silane was grafted onto the surface of graphene nanosheets (GNSs through free radical reactions, to form Si-O-Et functional groups that can undergo the sol-gel reaction. To improve the compatibility between the polymer matrix and the fillers, epoxy monomer was modified using a silane coupling agent; then, the functionalized GNSs were added to the modified epoxy to improve the thermal stability and strengthen the flame-retardant character of the composites. High-resolution X-ray photoelectron spectrometry reveals that when the double bonds in VTES are grafted to the surfaces of GNSs. Solid-state 29Si nuclear magnetic resonance presents that the distribution of the signal associated with the T3 structure is wide and significant, indicating that the functionalization reaction of the silicone in the modified epoxy and VTES-GNSs increases the network-like character of the structures. Thermal gravimetric analysis, the integral procedure decomposition temperature, and limiting oxygen index demonstrate that the GNSs composites that contained silicon had a higher thermal stability and stronger flame-retardant character than pure epoxy. The dynamic storage modulus of all of the m-GNSs containing composites was significantly higher than that of the control epoxy, and the modulus of the composites increased with the concentration of m-GNSs.

  7. Flyweight, Superelastic, Electrically Conductive, and Flame-Retardant 3D Multi-Nanolayer Graphene/Ceramic Metamaterial.

    Science.gov (United States)

    Zhang, Qiangqiang; Lin, Dong; Deng, Biwei; Xu, Xiang; Nian, Qiong; Jin, Shengyu; Leedy, Kevin D; Li, Hui; Cheng, Gary J

    2017-07-01

    A ceramic/graphene metamaterial (GCM) with microstructure-derived superelasticity and structural robustness is achieved by designing hierarchical honeycomb microstructures, which are composited with two brittle constituents (graphene and ceramic) assembled in multi-nanolayer cellular walls. Attributed to the designed microstructure, well-interconnected scaffolds, chemically bonded interface, and coupled strengthening effect between the graphene framework and the nanolayers of the Al 2 O 3 ceramic (NAC), the GCM demonstrates a sequence of multifunctional properties simultaneously that have not been reported for ceramics and ceramics-matrix-composite structures, such as flyweight density, 80% reversible compressibility, high fatigue resistance, high electrical conductivity, and excellent thermal-insulation/flame-retardant performance simultaneously. The 3D well-ordered graphene aerogel templates are strongly coupled with the NAC by the chemically bonded interface, exhibiting mutual strengthening, compatible deformability, and a linearly dependent relationship between the density and Young's modulus. Considerable size effects of the ceramic nanolayers on the mechanical properties are revealed in these ceramic-based metamaterials. The designed hierarchical honeycomb graphene with a fourth dimensional control of the ceramic nanolayers on new ways to scalable fabrication of advanced multifunctional ceramic composites with controllable design suggest a great potential in applications of flexible conductors, shock/vibration absorbers, thermal shock barriers, thermal insulation/flame-retardant skins, and porous microwave-absorbing coatings. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Recent Advances in the Design of Water Based-Flame Retardant Coatings for Polyester and Polyester-Cotton Blends

    Directory of Open Access Journals (Sweden)

    Jenny Alongi

    2016-10-01

    Full Text Available Over the last ten years a new trend of research activities regarding the flame retardancy of polymeric materials has arisen. Indeed, the continuous search for new flame retardant systems able to replace the traditional approaches has encouraged alternative solutions, mainly centred on nanotechnology. In this context, the deposition of nanostructured coatings on fabrics appears to be the most appealing and performance suitable approach. To this aim, different strategies can be exploited: from the deposition of a single monolayer consisting of inorganic nanoparticles (single-step adsorption to the building-up of more complex architectures derived from layer by layer assembly (multi-step adsorption. The present paper aims to review the application of such systems in the field of polyester and polyester-cotton blend fabrics. The results collated by the authors are discussed and compared with those published in the literature on the basis of the different deposition methods adopted. A critical analysis of the advantages and disadvantages exhibited by these approaches is also presented.

  9. Ethoxy (pentafluoro) cyclotriphosphazene (PFPN) as a multi-functional flame retardant electrolyte additive for lithium-ion batteries

    Science.gov (United States)

    Li, Xi; Li, Weikang; Chen, Lai; Lu, Yun; Su, Yuefeng; Bao, Liying; Wang, Jing; Chen, Renjie; Chen, Shi; Wu, Feng

    2018-02-01

    With the wide application of lithium-ion batteries (LiBs), safety performance is an important constraint on the commercialization of large-scale, high-capacity LIBs. The main reason for the safety problem is that the electrolyte of LiBs is highly flammable, especially under high temperature and high voltage. It is an effective method to improve the safety of cells by mixing flame retardant with conventional electrolyte comprising of LiPF6 and carbonates. Herein, ethoxy (pentafluoro) cyclotriphosphazene (PFPN) is studied as a high efficiency flame retardant. Adding 5 vol% of PFPN results in a non-flammable electrolyte with self-extinguishing time (SET) of 12.38 s g-1 and critical oxygen index (COI) of 22.9, without compromising the capacity of cathode material. The initial discharge capacity of the LiCoO2 electrode with 5% PFPN is 150.7 mAh g-1, with a capacity retention of 99.14% after 30 cycles at 0.1 C. The results show that 5 vol% is the best adding amount of PFPN for electrolyte, which can modify the solid electrolyte interface (SEI). Moreover, PFPN reduces charge transfer resistance of the cells, resulting decreased electrode polarization and enhanced electrochemistry performances at low temperature. These results have confirmed that PFPN has the potential to be a multi-function additive for commercial LIBs production.

  10. New halogenated flame retardants in the atmosphere of nine urban areas in China: Pollution characteristics, source analysis and variation trends.

    Science.gov (United States)

    Li, Qilu; Yang, Kong; Li, Kechang; Liu, Xin; Chen, Duohong; Li, Jun; Zhang, Gan

    2017-05-01

    Since the ban of polybrominated diphenyl ethers (PBDEs) excluding deca-BDE in China, new halogenated flame retardants (NHFRs), such as new brominated flame retardants and Dechlorane Plus, have become widely used. In this study, we assessed the atmospheric gaseous and particulate levels of eight NHFRs in nine urban areas in China. We detected high mean atmospheric (vapour plus particle phases) concentrations of tetrabromophthalate (TBPH) (74.8 pg m -3 ) and decabromodiphenyl ethane (DBDPE) (68.8 pg m -3 ), two major NHFRs. Most of the gaseous and particulate NHFR concentrations presented seasonal variations (from summer to autumn), possibly driven by temperature. Spatially, concentrations and patterns of the NHFRs differed among the nine cities. Significantly higher concentrations were detected in cities with higher gross domestic products. The composition, especially the DBDPE/TBPH ratio (S), were clearly different among the cities, which pattern in each city are likely driven by variations in the type of industries operating in each city. Based on the temporal analysis of other researches and our data, PBDE levels have decreased markedly, while NHFRs levels have increased. Since high NHFR levels had detrimental effects on public health, NHFRs research warrants more attention. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Removal of pharmaceuticals, polybrominated flame retardants and UV-filters from sludge by the fungus Trametes versicolor in bioslurry reactor

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Rodriguez, Carlos E. [Unitat Asociada de Biocatalisi Aplicada IQAC-CSIC, Escola d' Enginyeria, Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain); Centro de Investigacion en Contaminacion Ambiental, Universidad de Costa Rica, 2060 San Jose (Costa Rica); Baron, Enrique; Gago-Ferrero, Pablo; Jelic, Aleksandra; Llorca, Marta; Farre, Marinella; Diaz-Cruz, M. Silvia; Eljarrat, Ethel [Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA), Spanish Council for Scientific Research (CSIC), Jordi Girona 18-26, 08034 Barcelona (Spain); Petrovic, Mira [Institucio Catalana de Reserca i Estudis Avancats (ICREA), Passeig Lluis Companys 23, 80010 Barcelona (Spain); Catalan Institute for Water Research (ICRA), H2O Building, Scientific and Technological Park of the University of Girona, 101-E-17003 Girona (Spain); Caminal, Gloria, E-mail: Gloria.Caminal@uab.cat [Unitat Asociada de Biocatalisi Aplicada IQAC-CSIC, Escola d' Enginyeria, Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain); Barcelo, Damia [Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA), Spanish Council for Scientific Research (CSIC), Jordi Girona 18-26, 08034 Barcelona (Spain); Catalan Institute for Water Research (ICRA), H2O Building, Scientific and Technological Park of the University of Girona, 101-E-17003 Girona (Spain); King Saud University (KSU), P.O. Box 2455, 11451 Riyadh (Saudi Arabia); and others

    2012-09-30

    Highlights: Black-Right-Pointing-Pointer Sludge from a WWTP was treated in a fungal slurry reactor with Trametes versicolor. Black-Right-Pointing-Pointer Twenty-four pharmaceuticals were removed at important extents. Black-Right-Pointing-Pointer UV-filters and brominated flame retardants were also degraded. Black-Right-Pointing-Pointer Overall toxicity of sludge increased despite the pollutant removal. - Abstract: Conventional wastewater treatments are inefficient in the removal of many organic pollutants. The presence of these contaminants in the final sludge represents a source of environmental pollution due to the increasing use of biosolids in land application. A biotechnological approach which employed the fungus Trametes versicolor in a sludge-bioslurry reactor was assessed in order to remove several groups of emerging pollutants. Biological fungal activity was monitored by means of ergosterol and laccase determinations. Fifteen out of 24 detected pharmaceuticals were removed at efficiencies over 50% after the treatment, including eight completely degraded. Removal ranged between 16-53% and 22-100% for the brominated flame retardants and the UV-filters, respectively. Only two of all the detected compounds remained unchanged after the treatment. Although elimination results are promising, the toxicity of the final sludge increased after the treatment. This finding is contrary to the toxicity results obtained in similar treatments of sludge with T. versicolor in solid-phase.

  12. Impact of a novel phosphorus-nitrogen flame retardant curing agent on the properties of epoxy resin

    Science.gov (United States)

    Liu, Xiaoli; Liang, Bing

    2017-12-01

    A phosphorus-nitrogen flame retardant curing agent diethyl phosphonic p-Phenylenediamine diamide (DEPPPD) was synthesized. The chemical structure of the obtained compound was identified by Fourier transform infrared (FTIR), 1H nuclear magnetic resonance (1HNMR), and mass spectroscopies. A series of t hermosetting systems were prepared by conventional epoxy resins (E-44) and DEPPPD. The effects of DEPPPD on flame retardancy, thermal degradation behavior, mechanical properties and the morphologies of char residues of EP/DEPPPD thermosets were investigated. The results demonstrated that when the phosphorus content of 2.88 wt%, EP-3 successfully passed UL-94 V-0 flammability rating, the LOI value was as high as 31.1%, the impact strength and tensile strength of it was 6.50 KJ m-2 and 48.21 MPa, the adhesive strength could reach 14.61 MPa, respectively. The TGA results indicated that the introduction of DEPPPD promoted EP matrix decomposed at a lower temperature, the rate of the thermal decomposition also decreased compared with EP-0. The residual char ratio of 800 °C was increased whether in nitrogen or in the air. The morphological structures of char residue were more compact and homogeneous which could prevent the heat transmission and diffusion, limit the production of combustible gases and reduced the heat release rate.

  13. Advanced morphological - behavioral test platform reveals neurodevelopmental defects in embryonic zebrafish exposed to comprehensive suite of halogenated and organophosphate flame retardants.

    Science.gov (United States)

    Noyes, Pamela D; Haggard, Derik E; Gonnerman, Greg D; Tanguay, Robert L

    2015-05-01

    The increased use of flammable plastics and electronic devices along with stricter fire safety standards has led to the heavy use of flame retardant chemicals in many consumer, commercial, and industrial products. Although flame retardant use has increased, a great deal of uncertainty surrounds their safety with some evidence showing toxicity and risk to human and environmental health. Recent efforts have focused on designing high-throughput biological platforms with nonmammalian models to evaluate and prioritize chemicals with limited hazard information. To complement these efforts, this study used a new morphological and behavioral testing platform with embryonic zebrafish to characterize the developmental toxicity of 44 halogenated and organophosphate flame retardants, including several of their known metabolites. Zebrafish were exposed to flame retardants from 6 to 120 h post fertilization (hpf) across concentrations spanning 4 orders of magnitude (eg, 6.4 nM to 64 µM). Flame retardant effects on survival and development were evaluated at 24 and 120 hpf, and neurobehavioral changes were measured using 2 photomotor response (PMR) assays. Compared to controls, 93% (41/44) of flame retardants studied elicited adverse effects among one or more of the bioassays and concentrations tested with the aryl phosphate ester (APE)-based mono-isopropylated triaryl phosphate and the brominated-bisphenol-A analog tetrabromobisphenol-A producing the greatest array of malformations. Hierarchical clustering showed that APE flame retardants with isopropyl, butyl, and cresyl substituents on phenyl rings clustered tightly and were particularly potent. Both PMR assays were highly predictive of morphological defects supporting their use as nonlethal means of evaluating teratogenicity that could allow for additional evaluations of long-term or delayed effects in older animals. Taken together, evidence presented here indicates that zebrafish neurodevelopment is highly sensitive to

  14. Substituting environmentally relevant flame retardants: assessment fundamentals. Vol. 1: results and summary overview; Erarbeitung von Bewertungsgrundlagen zur Substitution umweltrelevanter Flammschutzmittel. Bd. 1: Ergebnisse und zusammenfassende Uebersicht

    Energy Technology Data Exchange (ETDEWEB)

    Leisewitz, A.; Kruse, H.; Schramm, E.

    2001-04-01

    The study examines the status, trends and alternatives (substitution and reduction potentials) in the use of flame retardants in selected product sectors: construction; electronics and electrical engineering; rail vehicles; textiles/upholstery. In addition, the study characterises thirteen flame retardants in terms of material flows, applications and toxicology/ecotoxicology. Vol. I: Summary overview of flame retardant applications in Germany in 1999/2000; characterisation of 13 flame retardants in terms of substance properties and application-specific characteristics, range of applications and quantities; derivation of assessment fundamentals for flame retardants, focussing on toxicology/ecotoxicology, suitability for closed-loop substance management, and potential for substitution and reduction; summary assessment of 13 flame retardants; summary overview of flame retardant applications. Vol. II: Analysis of flame retardant applications (state of the art, trends, alternatives) in: unsaturated polyester (UP) resins (rail vehicles); polyurethane (PU) insulating foams and one component foams (OCF) (construction sector); plastics for generic uses in electronic and electrical equipment, in casings for electronic and electrical equipment and in printed circuit boards (electronics/electrical engineering); and in upholstery and mattresses (textile applications). Vol. III: Toxicological/ecotoxicological profiles of substances: Decabromodiphenyl oxide; Tetrabromobisphenol A; Bis[pentabromophenyl]ethane; Hexabromocyclodo-decane, Tris[chloropropyl]phosphate, Resorcinol-bis-diphenylphosphate; N-Hydroxymethyl-3-dimethylphosphonopropionamide, Red phosphorus, Ammonium polyphosphate, Melamin cyanurate, Aluminiumtrihydroxide, Sodium borate decahydrate, Antimony trioxide. (orig.) [German] Untersucht werden Stand, Trends und Alternativen (Substitutions- und Minderungspotentiale) beim Einsatz von Flammschutzmitteln (FSM) in ausgewaehlten Produkten aus: Baubereich, Elektrotechnik

  15. Polyethylene flame retarded with expandable graphite and a novel intumescent additive

    CSIR Research Space (South Africa)

    Focke, WW

    2014-07-01

    Full Text Available retardant performance of this compound as a primary fire retardant and in combination with expandable graphite (EG) was evaluated by cone calorimetry. Cone calorimeter results showed that addition of 10 wt % EG alone lowers peak heat release rate (p...

  16. THE COMBINED EFFECT OF ORGANIC PHOSPHINATE BASED FLAME RETARDANT AND ZINC BORATE ON THE FIRE BEHAVIOR OF POLY(BUTYLENE TEREPHTHALATE

    Directory of Open Access Journals (Sweden)

    Mustafa Erdem ÜREYEN

    2016-12-01

    Full Text Available Neat poly(butylene terephthalate is highly combustible. It is not self-extinguishing, and after ignition it burns with dripping. To meet the fire safety requirements, it should be rendered flame retardant. The most common flame retardants for PBT are based on halogenated (most often brominated or phosphorus compounds. Although their efficiency is lower than halogen based flame retardants, expensive phosphorus based flame retardants for polyester are preferred, because of low smoke generation, nontoxicity and low corrosion properties. Zinc borate has been widely used with other flame retardants in wood products and in several polymers. In this work the fire behavior of zinc borate, phosphinic acid and zinc borate/phosphinic acid combination doped poly(butylene terephthalate was investigated. Firstly, the mean particle size of zinc borate (2ZnO.3B2O3.3.5H2O powders were reduced by attrition milling. Samples were produced by twin screw micro compounder. The fire properties of the ZnB, DPA and ZnB/DPA doped PBT were investigated and compared to each other by LOI and thermal analysis. LOI values of ZnB/PBT samples were found very low even with higher filling content. At higher loading of ZnB, the dripping of the sample strongly decreased and char residue increased. It was seen that organic diethyl phosphinic acid based additives DPA is particularly effective with PBT. It was found that the combination of DPA and ZnB can be used to increase the char residue, decrease spread of flame and the melt dripping of PBT.

  17. Investigating A Novel Flame Retardant Known as V6: Measurements in Baby Products, House Dust and Car Dust

    Science.gov (United States)

    Fang, Mingliang; Webster, Thomas F.; Gooden, David; Cooper, Ellen M.; McClean, Michael D.; Carignan, Courtney; Makey, Colleen; Stapleton, Heather M.

    2013-01-01

    With the phase-out of polybrominated diphenyl ether (PBDE) flame retardants, the use of new and alternate flame retardants has been increasing. 2,2-bis(chloromethyl)propane-1,3-diyltetrakis(2-chloroethyl) bisphosphate, known as V6, is a flame retardant applied to polyurethane foam commonly found in furniture and automobile foam. However, to the authors’ knowledge, no research has been conducted on V6 levels in the environment. The intention of this study was to measure the concentration of V6 in foam collected from baby products where it was recently detected, and measure levels in dust samples collected from homes and automobiles in the Boston, MA area. To accomplish this a pure V6 commercial standard was purchased from a Chinese manufacturer and purified (> 98%). An analytical method to measure V6 in dust samples using liquid chromatography tandem mass spectrometry (LC/MS-MS) was developed. Extraction was conducted using Accelerated Solvent Extraction (ASE) and extracts were purified using an ENVI-Florisil SPE column (500 mg, 3mL). V6 was measured in foam samples collected from baby products with a concentration ranging from 24,500,000 to 59,500,000 ng/g of foam (n = 12, average ± sd: 46,500,000 ± 12,000,000 ng/g; i.e., on average, 4.6 % of the foam mass was V6). V6 was also detected in 19 of 20 car dust samples and 14 of 20 house dust samples analyzed. The concentration of V6 in the house dust ranged from car dust with a median of 103.0 ng/g. Concentrations in car dust were significantly higher than the house dust, potentially indicating higher use of V6 in automobiles compared to products found in the home. Furthermore, tris (2-chloroethyl) phosphate (TCEP), a known carcinogen, was found in the V6 commercial mixture (14% by weight) as an impurity and was consistently detected with V6 in the foam samples analyzed. A significant correlation was also observed between V6 and TCEP in the dust samples, suggesting that the use of V6 is a significant source of TCEP

  18. Efficient Flame-Retardant and Smoke-Suppression Properties of Mg-Al-Layered Double-Hydroxide Nanostructures on Wood Substrate.

    Science.gov (United States)

    Guo, Bingtuo; Liu, Yongzhuang; Zhang, Qi; Wang, Fengqiang; Wang, Qingwen; Liu, Yixing; Li, Jian; Yu, Haipeng

    2017-07-12

    Improving the flame retardancy of wood is an imperative yet highly challenging step in the application of wood in densely populated spaces. In this study, Mg-Al-layered double-hydroxide (LDH) coating was successfully fabricated on a wood substrate to confer flame-retardant and smoke-suppression properties. The chemical compositions and bonding states characterized by energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy confirmed the coating constituents of Mg-Al LDH. The coating evenly covered the sample wood surfaces and provided both mechanical enhancement and flame-retardancy effects. The limiting oxygen index of the Mg-Al LDH-coated wood increased to 39.1% from 18.9% in the untreated wood. CONE calorimetry testing revealed a 58% reduction in total smoke production and a 41% reduction in maximum smoke production ratio in the Mg-Al LDH-coated wood compared to the untreated wood; the peak heat release rate and total heat release were also reduced by 49% and 40%, respectively. The Mg-Al LDH coating is essentially hydrophilic, but simple surface modification by fluoroalkyl silane could make it superhydrophobic, with a water contact angle of 152° and a sliding angle of 8.6°. The results of this study altogether suggest that Mg-Al LDH coating is a feasible and highly effective approach to nanoconstructing wood materials with favorable flame-retardant and smoke-suppression properties.

  19. Exposure to brominated flame retardants, perfluorinated compounds, phthalates and phenols in European birth cohorts: ENRIECO evaluation, first human biomonitoring results, and recommendations

    NARCIS (Netherlands)

    Casas, M.; Chevrier, C.; Hond, E.D.; Fernandez, M.F.; Pierik, F.; Philippat, C.; Slama, R.; Toft, G.; Vandentorren, S.; Wilhelm, M.; Vrijheid, M.

    2013-01-01

    There are emerging concerns about potential effects on child health and development of early-life exposure to substances such as brominated flame retardants (BFRs), perfluorinated compounds (PFCs), phthalates and phenols (including bisphenol A (BPA)); pregnancy and birth cohort studies are ideally

  20. Brominated flame retardant levels in human milk and serum from MAMA study participants: Correlations over time, matrix, and with questionnaire results

    Science.gov (United States)

    Brominated flame retardants (BFRs) are synthetic, lipophilic, and bioaccumulative compounds used to prevent the combustion of a variety of items including electronics and furniture. There are 75 classes of BFRs, two of which are the polybrominated biphenyls (PBB) and the polybrom...

  1. Nanomaterial Case Study: A Comparison of Multiwalled Carbon Nanotube and Decabromodiphenyl Ether Flame-Retardant Coatings Applied to Upholstery Textiles (Independent Peer Review Draft)

    Science.gov (United States)

    This Independent Peer Review Draft document presents a case study of multiwalled carbon nanotubes (MWCNTs); it focuses on the specific example of MWCNTs as used in flame-retardant coatings applied to upholstery textiles. This case study is organized around the comprehensive envir...

  2. The GhTT2_A07 gene is linked to the brown colour and natural flame retardancy phenotypes of Lc1 cotton (Gossypium hirsutum L.) fibres

    Science.gov (United States)

    Some naturally-coloured brown cotton fibres from accessions of Gossypium hirsutum can be used to make textiles with enhanced flame retardancy (FR). Several independent brown fibre loci have been identified and mapped to chromosomes, but the underlying genes have yet to be identified, and the mechan...

  3. Toddler exposure to flame retardant chemicals : Magnitude, health concern and potential risk- or protective factors of exposure: Observational studies summarized in a systematic review

    NARCIS (Netherlands)

    Sugeng, Eva J; de Cock, Marijke; Schoonmade, Linda J; van de Bor, Margot

    2017-01-01

    Endocrine disrupting flame retardant (FR) chemicals form a human health concern, that is investigated mostly from the perspective of adult- and early life exposure. No overview of studies on toddler exposure and health effects exist. However, toddlerhood is a critical developmental period and

  4. A comparison of the in vitro cyto- and neurotoxicity of brominated and halogen-free flame retardants : prioritization in search for safe(r) alternatives

    NARCIS (Netherlands)

    Hendriks, Hester S; Meijer, Marieke; Muilwijk, Mirthe; van den Berg, Martin; Westerink, Remco H S

    Brominated flame retardants (BFRs) are abundant persistent organic pollutants with well-studied toxicity. The toxicological and ecological concerns associated with BFRs argue for replacement by safe(r) alternatives. Though previous research identified the nervous system as a sensitive target organ

  5. Gene Transcription, Metabolite and Lipid Profiling in Eco-Indicator Daphnia magna Indicate Diverse Mechanisms of Toxicity by Legacy and Emerging Flame-Retardants

    Science.gov (United States)

    The use of chemical flame-retardants (FR) in consumer products has steadily increased over the last 30 years. Toxicity data exist for legacy FRs such as pentabromodiphenyl ether (pentaBDE), but less is known about effects of new formulations. To address this issue, the toxicity o...

  6. Dust Measurement of Two Organophosphorus Flame Retardants, Resorcinol Bis(diphenylphosphate) (RBDPP) and Bisphenol A Bis(diphenylphosphate) (BPA-BDPP), Used as Alternatives for BDE-209

    NARCIS (Netherlands)

    Brandsma, S.H.; Sellström, U.; de Wit, C.A.; de Boer, J.; Leonards, P.E.G.

    2013-01-01

    Resorcinol bis(diphenylphosphate) (RBDPP) and bisphenol A bis(diphenylphosphate) (BPA-BDPP) are two halogen-free organophosphorus flame retardant (PFRs) that are used as an alternative for the decabromodiphenyl ether (Deca-BDE) technical mixture in TV/flatscreen housing and other electronic consumer

  7. The Effects of a Macromolecular Charring Agent with Gas Phase and Condense Phase Synergistic Flame Retardant Capability on the Properties of PP/IFR Composites

    Science.gov (United States)

    Chen, Hongda; Wang, Jihui; Ding, Anxin; Han, Xia; Sun, Ziheng

    2018-01-01

    In order to improve the efficiency of intumescent flame retardants (IFRs), a novel macromolecular charring agent named poly(ethanediamine-1,3,5-triazine-p-4-amino-2,2,6,6-tetramethylpiperidine) (PETAT) with gas phase and condense phase synergistic flame-retardant capability was synthesized and subsequently dispersed into polypropylene (PP) in combination with ammonium polyphosphate (APP) via a melt blending method. The chemical structure of PETAT was investigated by Fourier transform infrared spectroscopy (FTIR), and 1H nuclear magnetic resonance (NMR) spectroscopy. Thermal properties of the PETAT and IFR systems were tested by thermogravimetric-derivative thermogravimetric analysis (TGA-DTG) and thermogravimetry–Fourier transform infrared spectroscopy (TG-FTIR). The mechanical properties, thermal stability, flame-retardant properties, water resistance, and structures of char residue in flame-retardant composites were characterized using tensile and flexural strength property tests, TGA, limiting oxygen index (LOI) values before and after soaking, underwritten laboratory-94 (UL-94) vertical burning test, cone calorimetric test (CCT), scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDXS), and FTIR. The results indicated that PETAT was successfully synthesized, and when the ratio of APP to PETAT was 2:1 with 25 wt % loading, the novel IFR system could reduce the deterioration of tensile strength and enhance the flexural strength of composites. Meanwhile, the flame-retardant composite was able to pass the UL-94 V-0 rating with an LOI value of 30.3%, and the peak of heat release rate (PHRR), total heat release (THR), and material fire hazard values were considerably decreased compared with others. In addition, composites also exhibited excellent water resistance properties compared with traditional IFR composites. SEM-EDXS and FTIR analyses of the char residues, as well as TG-FTIR analyses of IFR were used to investigate the flame-retardant

  8. The Effects of a Macromolecular Charring Agent with Gas Phase and Condense Phase Synergistic Flame Retardant Capability on the Properties of PP/IFR Composites.

    Science.gov (United States)

    Chen, Hongda; Wang, Jihui; Ni, Aiqing; Ding, Anxin; Han, Xia; Sun, Ziheng

    2018-01-11

    In order to improve the efficiency of intumescent flame retardants (IFRs), a novel macromolecular charring agent named poly(ethanediamine-1,3,5-triazine-p-4-amino-2,2,6,6-tetramethylpiperidine) (PETAT) with gas phase and condense phase synergistic flame-retardant capability was synthesized and subsequently dispersed into polypropylene (PP) in combination with ammonium polyphosphate (APP) via a melt blending method. The chemical structure of PETAT was investigated by Fourier transform infrared spectroscopy (FTIR), and ¹H nuclear magnetic resonance (NMR) spectroscopy. Thermal properties of the PETAT and IFR systems were tested by thermogravimetric-derivative thermogravimetric analysis (TGA-DTG) and thermogravimetry-Fourier transform infrared spectroscopy (TG-FTIR). The mechanical properties, thermal stability, flame-retardant properties, water resistance, and structures of char residue in flame-retardant composites were characterized using tensile and flexural strength property tests, TGA, limiting oxygen index (LOI) values before and after soaking, underwritten laboratory-94 (UL-94) vertical burning test, cone calorimetric test (CCT), scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDXS), and FTIR. The results indicated that PETAT was successfully synthesized, and when the ratio of APP to PETAT was 2:1 with 25 wt % loading, the novel IFR system could reduce the deterioration of tensile strength and enhance the flexural strength of composites. Meanwhile, the flame-retardant composite was able to pass the UL-94 V-0 rating with an LOI value of 30.3%, and the peak of heat release rate (PHRR), total heat release (THR), and material fire hazard values were considerably decreased compared with others. In addition, composites also exhibited excellent water resistance properties compared with traditional IFR composites. SEM-EDXS and FTIR analyses of the char residues, as well as TG-FTIR analyses of IFR were used to investigate the flame-retardant

  9. Contamination and distribution of heavy metals, polybrominated diphenyl ethers and alternative halogenated flame retardants in a pristine mangrove.

    Science.gov (United States)

    Wu, Qihang; Leung, Jonathan Y S; Tam, Nora F Y; Peng, Yisheng; Guo, Pengran; Zhou, Song; Li, Qing; Geng, Xinhua; Miao, Shenyu

    2016-02-15

    Owing to the expanding metal and electronics industries, pollution in the Pearl River Estuary needs special concern. Given the hydrodynamic effect, the pristine mangrove in Qi'ao Island would be contaminated by tidal flushing. Thus, we examined (1) the contamination of pollutants in this mangrove, including heavy metals, polybrominated diphenyl ethers (PBDEs) and alternative halogenated flame retardants (AHFRs), and (2) how habitat characteristics and sediment properties affect their distribution. Results showed that the sediment in Qi'ao mangrove had higher concentrations of heavy metals, PBDEs and AHFRs than that in other pristine mangroves, and similar concentrations to those mangroves impacted by point sources. Heavy metal concentrations were lower in the vegetated areas than mudflat, while the opposite was found for PBDEs and AHFRs. The findings imply that tidal flushing was an important pollution source, while mangrove plants have the capacity to minimize the impact of heavy metals, but not PBDEs and AHFRs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. The preparation of layered double hydroxide wrapped carbon nanotubes and their application as a flame retardant for polypropylene

    International Nuclear Information System (INIS)

    Du Baoxian; Fang Zhengping

    2010-01-01

    Carbon nanotubes (CNTs) wrapped with layered double hydroxide (LDH-w-CNTs) were facilely obtained through in situ introduction of CNTs into the hydrothermal reaction system of LDH, with the goal of combining their unique physical and chemical characteristics to meet new advanced applications. Morphological observations indicated that LDH lamellae enwrapped the surface of CNTs and the wrapping degree was dependent on the functionalization of CNTs. ζ-potential measurements showed that the interaction between the positive charge of LDH and the negative charge of CNTs was the main driving force of the wrapping process. Both hybrids led to a reduction in the peak heat release rate (PHRR) of polypropylene, indicating that they could confer better flame retardancy on polypropylene with respect to LDH and CNTs.

  11. Influence of the flame retardant tetrabromobisphenol-A on the expression of cytochrome P450 isoenzymes in rat liver

    Energy Technology Data Exchange (ETDEWEB)

    Germer, S.; Schmitz, H.J.; Schrenk, D. [Food Chemistry and Environmental Toxicology, Univ. of Kaiserslautern (Germany); Piersma, A.H.; Ven, L. van der [Lab. for Toxicology, Pathology and Genetics, National Inst. for Public Health and the Environment RIVM, Bilthoven (Netherlands)

    2004-09-15

    As one of the major brominated flame retardants (BFRs) tetrabromobisphenol A (TBBPA) is widely used in flammable plastic materials. There, it is incorporated either as covalently binding BFR or as an additive leading to likely leaching out of goods. Indeed, TBBPA was found in indoor air, environmental and human samples, i.e. mother's milk. Thus a certain degree of risk for human has to be considered. Some BFRs have been suspected to act as endocrine disrupters and/or affect the development of the unborn. Induction of drug metabolism may play a role in such effects by changing the body's homeostasis of hormones, such as steroids, thyroxine, and others. BFRs are prospected to lead to thyroid hormone deficiencies, neurodevelopmental deficiencies, cancer. Furthermore a variety of inducing agents have been described as tumor promoters in rodent liver. Herein the induction of enzymes of the cytochrome P450 family (CYP) plays a major role.

  12. Flame Retardant: Cyberbullies Torment Their Victims 24/7: Here's How to Stop the Abuse

    Science.gov (United States)

    Willard, Nancy

    2006-01-01

    Cyberbullying is the use of electronic information such as e-mail and other digital age tools to bully or harass individuals. Cyberbullies post angry and vulgar messages in online "flaming" wars or hack into a peer's e-mail account to wreak havoc, assaulting the reputations and already fragile egos of their young victims. The devastating effects…

  13. Measurements in flame retardant textiles and protective clothing using an instrumented

    Science.gov (United States)

    Kort-Kamp, V. M.; Santos, A. M.; Azevedo, A. F.; Lima, R. M. V.; Bittencourt, E.

    2018-03-01

    The flame test manikin system can be used to evaluate the performance of thermal protective clothing under fire simulation conditions. Different weights of thermal protective garments were tested and the total clothed burn injury area decreased as the fabric weight increased. In addition, a comparison of different compositions for the same weight was analyzed too.

  14. the use of castor oil as a flame retardant in polyurethane foam

    African Journals Online (AJOL)

    Dr Abdusalam

    ABSTRACT. Thirteen polyurethane foam samples were prepared with varying quantity of castor oil as a reactant with polyisocyanate and their flammability test was carried out using various flame test procedures. Physical properties of the foam samples were found to increase with the increasing in the quantity of castor oil.

  15. Concentrations and trends of halogenated flame retardants in the pooled serum of residents of Laizhou Bay, China.

    Science.gov (United States)

    He, Songjie; Li, Mingyuan; Jin, Jun; Wang, Ying; Bu, Yunjie; Xu, Meng; Yang, Xianfeng; Liu, Anming

    2013-06-01

    The south coast of Laizhou Bay, in northeastern China, is a production area for halogenated flame retardants (HFR). In 2007, the authors measured serum concentrations of polybrominated diphenyl ethers (PBDEs) in Laizhou Bay residents. To assess the PBDE concentration trend, and determine the concentrations of the emerging flame retardants Dechlorane Plus (DP) and bis(2-ethylhexyl)-3,4,5,6-tetrabromophthalate (TBPH), the authors measured the concentrations of 8 PBDE congeners, 2 DP isomers, and TBPH in 10 composite samples, which were pooled from the serum collected from 305 Laizhou Bay residents in October 2011. The average concentration of the total PBDE (∑8 PBDE) concentration in all serum pools was 240 ng/g lipid weight, and the highest serum pool concentration (in the 30- to 39-yr-old male group) was 780 ng/g lipid weight. Brominated diphenyl ether-209 was the dominant congener, accounting for 87% of ∑8 PBDE. Compared with a previous study, ∑8 PBDE serum concentrations in the present study showed no change in order of magnitude, but the relative contribution of BDE-209 to ∑8 PBDE was higher. The average concentration of ∑DP in all serum pools was 3.6 ng/g lipid weight, ranging from 1.4 ng/g lipid weight (in the 50- to 59-yr-old male group) to 11 ng/g lipid weight (in the 20- to 29-yr-old male group). The concentration of DP was lower than in other reported studies. The study also detected TBPH in the 30- to 39-yr-old female group, suggesting that TBPH, as an emerging HFR, requires further monitoring. Copyright © 2013 SETAC.

  16. Trends in the levels of halogenated flame retardants in the Great Lakes atmosphere over the period 2005-2013.

    Science.gov (United States)

    Liu, Liang-Ying; Salamova, Amina; Venier, Marta; Hites, Ronald A

    2016-01-01

    Air (vapor and particle phase) samples were collected every 12days at five sites near the North American Great Lakes from 1 January 2005 to 31 December 2013 as a part of the Integrated Atmospheric Deposition Network (IADN). The concentrations of 35 polybrominated diphenyl ethers (PBDEs) and eight other halogenated flame retardants were measured in each of the ~1,300 samples. The levels of almost all of these flame retardants, except for pentabromoethylbenzene (PBEB), hexabromobenzene (HBB), and Dechlorane Plus (DP), were significantly higher in Chicago, Cleveland, and Sturgeon Point. The concentrations of PBEB and HBB were relatively high at Eagle Harbor and Sturgeon Point, respectively, and the concentrations of DP were relatively high at Cleveland and Sturgeon Point, the two sites closest to this compound's production site. The data were analyzed using a multiple linear regression model to determine significant temporal trends in these atmospheric concentrations. The concentrations of PBDEs were decreasing at the urban sites, Chicago and Cleveland, but were generally unchanging at the remote sites, Sleeping Bear Dunes and Eagle Harbor. The concentrations of PBEB were decreasing at almost all sites except for Eagle Harbor, where the highest PBEB levels were observed. HBB concentrations were decreasing at all sites except for Sturgeon Point, where HBB levels were the highest. DP concentrations were increasing with doubling times of 3-9years at all sites except those closest to its source (Cleveland and Sturgeon Point). The levels of 1,2-bis(2,4,6-tribromophenoxy)ethane (TBE) were unchanging at the urban sites, Chicago and Cleveland, but decreasing at the suburban and remote sites, Sturgeon Point and Eagle Harbor. The atmospheric concentrations of 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EHTBB) and bis(2-ethylhexyl)-tetrabromophthalate (BEHTBP) were increasing at almost every site with doubling times of 3-6years. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Legacy and alternative flame retardants in Norwegian and UK indoor environment: Implications of human exposure via dust ingestion.

    Science.gov (United States)

    Kademoglou, Katerina; Xu, Fuchao; Padilla-Sanchez, Juan Antonio; Haug, Line Småstuen; Covaci, Adrian; Collins, Chris D

    2017-05-01

    Indoor dust has been acknowledged as a major source of flame retardants (FRs) and dust ingestion is considered a major route of exposure for humans. In the present study, we investigated the presence of PBDEs and alternative FRs such as emerging halogenated FRs (EHFRs) and organophosphate flame retardants (PFRs) in indoor dust samples from British and Norwegian houses as well as British stores and offices. BDE209 was the most abundant PBDE congener with median concentrations of 4700ngg -1 and 3400ngg -1 in UK occupational and house dust, respectively, 30 and 20 fold higher than in Norwegian house dust. Monomeric PFRs (m-PFRs), including triphenyl phosphate (TPHP), tris(chloropropyl) phosphate (TCPP) and tris(2-chloroethyl) phosphate (TCEP) dominated all the studied environments. To the best of our knowledge, this is the first report of isodecyldiphenyl phosphate (iDPP) and trixylenyl phosphate (TXP) in indoor environments. iDPP was the most abundant oligomeric PFR (o-PFR) in all dust samples, with median concentrations one order of magnitude higher than TXP and bisphenol A bis(diphenyl phosphate (BDP). iDPP and TXP worst-case scenario exposures for British workers during an 8h exposure in the occupational environment were equal to 34 and 1.4ngkgbw -1 day -1 , respectively. The worst-case scenario for BDE209 estimated exposure for British toddlers (820ngkgbw -1 day -1 ) did not exceeded the proposed reference dose (RfD) (7000ngkgbw -1 day -1 ), while exposures for sum of m-PFRs (Σm-PFRs) in British toddlers and adults (17,900 and 785ngkgbw -1 day -1 respectively) were an order of magnitude higher than for Norwegian toddlers and adults (1600 and 70ngkgbw -1 day -1 ). Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Evaluation of long-range transport potential of selected brominated flame retardants with measured 1-octanol-air partition coefficients

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun Jeong; Kwon, Jung Hwan [Div. of Environmental Science and Ecological Engineering, Korea University, Seoul (Korea, Republic of)

    2016-10-15

    Various alternative flame retardants are used in many countries since polybrominated diphenyl ethers (PBDEs) were classified as persistent organic pollutants (POPs). However, difficulties in the evaluation of the long-range transport potential (LRTP) of the alternatives are related to the lack of information on their physicochemical properties, which govern their environmental fates and transport. Based on the simulation of LRTP using OECD P{sub OV} and LRTP Screening Tool, five alternative brominated flame retardants (BFRs) (hexabromobenzene [HBB], 2,3,4,5,6-pentabromotoluene [PBT], 2,3,4,5,6-pentabromoethylbenzene [PBEB], 2-ethylhexyl 2,3,4,5-tetrabromobenzoate [TBB], and 1,2,4,5-tetrabromo-3,6-dimethylbenzene [TBX]), and 3 PBDEs (BDE-28, BDE-47, and BDE-99) were chosen to perform a refined assessment. This was done using an experimentally measured 1-octanol–air partition coefficient (K{sub OA}) for the calculation of the air–water partition coefficient (K{sub AW}) required for the model. The four selected alternative BFRs (HBB, PBT, PBEB, TBX) have K{sub OA} values close to the in silico estimation used in the screening evaluation. On the other hand, the measured K{sub OA} value for TBB was two orders of magnitude lower than the estimated value used in the screening simulation. The refined simulation showed that characteristic travel distance (CTD) and transfer efficiency (TE) for HBB, PBT, PBEB, and TBX were greater than those for BDE-28, whereas CTD and TE for TBB were lower than those for BDE-28. This suggested that TBB has a lower LRTP than BDE-28, considering the refined partition coefficients.

  19. Atmospheric concentrations of halogenated flame retardants at two remote locations: The Canadian High Arctic and the Tibetan Plateau

    International Nuclear Information System (INIS)

    Xiao Hang; Shen Li; Su, Yushan; Barresi, Enzo; DeJong, Maryl; Hung, Hayley; Lei, Ying-Duan; Wania, Frank; Reiner, Eric J.; Sverko, Ed; Kang, Shi-Chang

    2012-01-01

    Atmospheric concentrations of halogenated flame retardants (FRs) were monitored for approximately one year at two remote stations, namely Nam Co on the Tibetan Plateau and Alert in the Canadian High Arctic. BDE-47 and 99 were the dominant polybrominated diphenyl ether (PBDE) congeners at both sites. Atmospheric PBDE concentrations in Nam Co were generally lower than those at Alert. While significant seasonal variations were observed for PBDEs at Alert, the FR concentrations at Nam Co showed no significant seasonality, even though air masses originated from distinctly different regions during different seasons. This suggests that FRs in Tibet do not have regional sources, but are reflective of truly global background contamination. Three new FRs, namely 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), 2-ethyl-1-hexyl-2,3,4,5-tetrabromobenzoate (EHTeBB) and bis(2-ethyl-1-hexyl)tetrabromophthalate (TBPH) were detected at relatively high concentrations at both sites. This is the first report of these FRs in the remote global atmosphere and suggests significant potential for long-range atmospheric transport. - Highlights: ► First year-round measurements of FRs in the atmosphere of the Tibetan Plateau. ► PBDEs in Tibet are reflective of truly global background levels. ► Orographic precipitation limits the transport of particle-bound chemicals. ► First study of BTBPE, EHTeBB and TBPH in the Arctic and Tibetan air. ► These new FRs may have significant long-range atmospheric transport potential. - Several brominated flame retardants (BTBPE, EHTeBB, TBPH) were present in the atmosphere of the Arctic and the Tibetan Plateau at levels similar to those of the PBDEs.

  20. Levels of brominated flame retardants and other pesistent organic pollutants in breast milk samples from Limpopo province, South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Darnerud, Per Ola, E-mail: poda@slv.se [Toxicology Division, National Food Administration, P.O. Box 622, SE-751 26 Uppsala (Sweden); Aune, Marie; Larsson, Lotta [Chemistry Division 2, National Food Administration, P.O. Box 622, SE-751 26 Uppsala (Sweden); Lignell, Sanna [Toxicology Division, National Food Administration, P.O. Box 622, SE-751 26 Uppsala (Sweden); Mutshatshi, Tshinanne; Okonkwo, Jonathan; Botha, Ben [Faculty of Science, Tshwane University of Technology, Pretoria (South Africa); Agyei, Nana [Department of Chemistry, Limpopo University, Medunsa (South Africa)

    2011-09-01

    The non-occupational exposure to brominated flame retardants, and other persistent organic pollutants (POPs) was studied by collecting human breast milk samples from mothers residing in Thohoyandou area, a rural district in the Limpopo Province, northern part of South Africa (SA). Of all collected samples to be analysed (n = 28), those with large enough milk volumes, (n = 14) were quantified for polybrominated diphenyl ethers (PBDEs) (9 congeners: BDE-28, 47, 66, 99, 100, 138, 153, 154, and 183) and hexabromocyclododecane (HBCD) on a GC equipped with dual capillary columns and dual electron-capture detectors (ECD). The levels of PBDE congeners (median sumBDE 1.3 ng/g of lipids) and of HBCD were not far from levels generally found in European studies, and this study may be the first report on the presence of PBDEs and HBCD in SA breast milk. On a congener basis, the finding of comparably high BDE-183 levels suggests a specific PBDE usage, or contamination situation in SA. Apart from BFRs, the high DDT levels found in the breast milk from this area (median and maximum sumDDT levels of about 4 600 and over 20 000 ng/g of lipids, respectively; n = 28) have earlier been reported. In addition, other POPs (PCBs, HCB and HCHs) were found in SA breast milk, at relatively low levels. To conclude, measurable levels of PBDEs and HBCD, and a specific BDE congener pattern, were found in breast milk from the Limpopo province, SA. A number of other POPs, including DDTs in high levels, were also present. - Highlights: {yields} Persistent organic pollutants (POPs) were analysed in South African breast milk. {yields} Focus of interest were brominated flame retardants (BRFs). {yields} Sampling area was the rural Limpopo Province, northern SA. {yields} Probably the first reported African data on BFRs (PBDEs, HBCD) in breast milk. {yields} Reported BFR data similar to European levels.

  1. Developmental exposure to organophosphate flame retardants elicits overt toxicity and alters behavior in early life stage zebrafish (Danio rerio).

    Science.gov (United States)

    Dishaw, Laura V; Hunter, Deborah L; Padnos, Beth; Padilla, Stephanie; Stapleton, Heather M

    2014-12-01

    Organophosphate flame retardants (OPFRs) are common replacements for the phased-out polybrominated diphenyl ethers (PBDEs) and have been detected at high concentrations in environmental samples. OPFRs are structurally similar to organophosphate pesticides and may adversely affect the developing nervous system. This study evaluated the overt toxicity, uptake, and neurobehavioral effects of tris (1,3-dichloro-2-propyl) phosphate (TDCPP), tris (2-chloroethyl) phosphate (TCEP), tris (1-chloro-2-propyl) phosphate (TCPP), and tris (2,3-dibromopropyl) phosphate (TDBPP) in early life stage zebrafish. Chlorpyrifos was used as a positive control. For overt toxicity and neurobehavioral assessments, zebrafish were exposed from 0 to 5 days postfertilization (dpf). Hatching, death, or malformations were evaluated daily. Teratogenic effects were scored by visual examination on 6 dpf. To evaluate uptake and metabolism, zebrafish were exposed to 1 µM of each organophosphate (OP) flame retardant and collected on 1 and 5 dpf to monitor accumulation. Larval swimming activity was measured in 6 dpf larvae to evaluate neurobehavioral effects of exposures below the acute toxicity threshold. TDBPP elicited the greatest toxicity at >1 µM. TDCPP and chlorpyrifos were overtly toxic at concentrations ≥10 µM, TCEP, and TCPP were not overtly toxic at the doses tested. Tissue concentrations increased with increasing hydrophobicity of the parent chemical after 24 h exposures. TDCPP and TDBPP and their respective metabolites were detected in embryos on 5 dpf. For all chemicals tested, developmental exposures that were not overtly toxic significantly altered larval swimming activity. These data indicate that OPFRs adversely affect development of early life stage zebrafish. © The Author 2014. Published by Oxford University Press on behalf of the Society of Toxicology.All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  2. The effect of mineral fillers on the rheological, mechanical and thermal properties of halogen-free flame-retardant polypropylene/expandable graphite compounds

    Science.gov (United States)

    Mattausch, Hannelore; Laske, Stephan; Hohenwarter, Dieter; Holzer, Clemens

    2015-05-01

    In many polyolefin applications, such as electrical cables or automotive applications, the fire protection is a very important task. Unfortunately flame-retardant polymeric materials are often halogenated and form toxic substances in case of fire, which explains the general requirement to reduce the halogen content to zero. Non-halogenated, state-of-the-art flame retardants must be incorporated into the polymer in very high grades (> 40 wt%) leading to massive decrease in mechanical properties and/or processability. In this research work halogen-free flame-retardant polypropylene (PP) /expandable graphite (EG) were filled with minerals fillers such as layered silicates (MMT), magnesium hydroxide (MgOH), zeolite (Z) and expanded perlite (EP) in order to enhance the flame-retardant effect. The rheological, mechanical and thermal properties of these materials were investigated to gain more fundamental knowledge about synergistic combinations of flame-retardants and other additives. The rheological properties were characterized with a rotational rheometer with plate-plate setup. The EG/EP/PP compound exhibited the highest increase in viscosity (˜ 37 %). As representative value for the mechanical properties the Young's modulus was chosen. The final Young's modulus values of the twofold systems gained higher values than the single ones. Thermo gravimetric analysis (TGA) was utilized to investigate the material with respect to volatile substances and combustion behavior. All materials decomposed in one-step degradation. The EG filled compounds showed a significant increase in sample weight due to the expansion of EG. The combustion behavior of these materials was characterized by cone calorimeter tests. Especially combinations of expandable graphite with mineral fillers exhibit a reduction of the peak heat release rate during cone calorimeter measurements of up to 87% compared to pure PP.

  3. Effects of neonatal exposure to the flame retardant tetrabromobisphenol-A, aluminum diethylphosphinate or zinc stannate on long-term potentiation and synaptic protein levels in mice.

    Science.gov (United States)

    Hendriks, Hester S; Koolen, Lucas A E; Dingemans, Milou M L; Viberg, Henrik; Lee, Iwa; Leonards, Pim E G; Ramakers, Geert M J; Westerink, Remco H S

    2015-12-01

    Brominated flame retardants such as tetrabromobisphenol-A (TBBPA) may exert (developmental) neurotoxic effects. However, data on (neuro)toxicity of halogen-free flame retardants (HFFRs) are scarce. Recent in vitro studies indicated a high neurotoxic potential for some HFFRs, e.g., zinc stannate (ZS), whereas the neurotoxic potential of other HFFRs, such as aluminum diethylphosphinate (Alpi), appears low. However, the in vivo (neuro)toxicity of these compounds is largely unknown. We therefore investigated effects of neonatal exposure to TBBPA, Alpi or ZS on synaptic plasticity in mouse hippocampus. Male C57bl/6 mice received a single oral dose of 211 µmol/kg bw TBBPA, Alpi or ZS on postnatal day (PND) 10. On PND 17-19, effects on hippocampal synaptic plasticity were investigated using ex vivo extracellular field recordings. Additionally, we measured levels of postsynaptic proteins involved in long-term potentiation (LTP) as well as flame retardant concentrations in brain, muscle and liver tissues. All three flame retardants induced minor, but insignificant, effects on LTP. Additionally, TBBPA induced a minor decrease in post-tetanic potentiation. Despite these minor effects, expression of selected synaptic proteins involved in LTP was not affected. The flame retardants could not be measured in significant amounts in the brains, suggesting low bioavailability and/or rapid elimination/metabolism. We therefore conclude that a single neonatal exposure on PND 10 to TBBPA, Alpi or ZS does affect neurodevelopment and synaptic plasticity only to a small extent in mice. Additional data, in particular on persistence, bioaccumulation and (in vivo) toxicity, following prolonged (developmental) exposure are required for further (human) risk assessment.

  4. Growth of high-density ZnO nanorods on wood with enhanced photostability, flame retardancy and water repellency

    Science.gov (United States)

    Kong, Lizhuo; Tu, Kunkun; Guan, Hao; Wang, Xiaoqing

    2017-06-01

    Zinc oxide (ZnO) nanorod arrays were successfully assembled on the wood surface in situ via a two-step process consisting of formation of ZnO seeds and subsequent crystal growth under hydrothermal conditions at a low temperature. The morphology and crystalline structure of the formed ZnO nanorods were studied by field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). Highly dense and uniform arrays of ZnO nanorods with well-defined hexagonal facets were generated on the wood surface by tuning the concentration of the ZnO growth solution during the hydrothermal treatment. Accelerated weathering tests indicated that the assembled ZnO nanorod arrays were highly protective against UV radiation and greatly enhanced the photostability of the coated wood. Meanwhile, the ZnO nanorod-coated wood can withstand continuous exposure to flame with only minor smoldering in contrast with the pristine wood catching fire easily and burning rapidly. Moreover, when further modified with low-surface-energy stearic acid, the ZnO nanorod decorated wood surface can be transformed into a superhydrophobic surface, with a water contact angle (CA) of ∼154°. Such ZnO nanorod-modified woods with enhanced photostability, flame retardancy and water repellency offer an interesting alternative to conventional wood preservation strategies, highlighting their potential applications in some novel wood products.

  5. Flame retardancy and UV protection of cotton based fabrics using nano ZnO and polycarboxylic acids.

    Science.gov (United States)

    El-Hady, M M Abd; Farouk, A; Sharaf, S

    2013-01-30

    This research mainly deals with a novel flame-retardant and UV-protection for cellulosic fabrics using ZnO nanoparticles. We present the preparation and application of ZnO nanoparticles. The size of the prepared nanoparticles was analysed using dynamic light scattering (DLS). The application of nano ZnO on cellulosic fabrics (cotton 100% and cotton/cotton polyester 65/35%) was achieved by using different polycarboxilic acids (succinic acid [SA] and 1,2,3,4-butane tetracarboxilic acids [BTCA]) with sodium hypophosphite (SHP) as catalyst through conventional pad-dry-cure method. The effect of concentration of SHP on the physical properties, flammability and UV-protection of cross-linked fabrics are investigated. The effect of concentration of zinc oxide nanoparticles and the effect of curing temperature were also investigated. The results revealed the importance of SHP in increasing the flame-redundancy of the treated cellulosic fabrics. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Growth of high-density ZnO nanorods on wood with enhanced photostability, flame retardancy and water repellency

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Lizhuo; Tu, Kunkun; Guan, Hao [Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091 (China); Wang, Xiaoqing, E-mail: wangxq@caf.ac.cn [Research Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing 100091 (China); Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091 (China)

    2017-06-15

    Highlights: • ZnO nanorod arrays were deposited on the wood surface via a hydrothermal process. • The assembled ZnO nanorod arrays greatly enhanced the photostability of wood. • The treated wood can sustain direct exposure to flame with only minor smoldering. • The ZnO-coated wood modified with stearic acid showed a superhydrophobic surface. - Abstract: Zinc oxide (ZnO) nanorod arrays were successfully assembled on the wood surface in situ via a two-step process consisting of formation of ZnO seeds and subsequent crystal growth under hydrothermal conditions at a low temperature. The morphology and crystalline structure of the formed ZnO nanorods were studied by field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). Highly dense and uniform arrays of ZnO nanorods with well-defined hexagonal facets were generated on the wood surface by tuning the concentration of the ZnO growth solution during the hydrothermal treatment. Accelerated weathering tests indicated that the assembled ZnO nanorod arrays were highly protective against UV radiation and greatly enhanced the photostability of the coated wood. Meanwhile, the ZnO nanorod-coated wood can withstand continuous exposure to flame with only minor smoldering in contrast with the pristine wood catching fire easily and burning rapidly. Moreover, when further modified with low-surface-energy stearic acid, the ZnO nanorod decorated wood surface can be transformed into a superhydrophobic surface, with a water contact angle (CA) of ∼154°. Such ZnO nanorod-modified woods with enhanced photostability, flame retardancy and water repellency offer an interesting alternative to conventional wood preservation strategies, highlighting their potential applications in some novel wood products.

  7. Occurrence and source apportionment of halogenated flame retardants in the indoor air of Nepalese cities: Implication on human health

    Science.gov (United States)

    Yadav, Ishwar Chandra; Devi, Ningombam Linthoingmabi; Li, Jun; Zhang, Gan

    2017-07-01

    Elevated level of brominated- and chlorinated-flame retardants (FRs) have been accounted in ambient air across the globe. Despite what might be expected, restricted information is available on PBDEs and other halogenated FR contained indoor air in whole of Indian sub-continent especially in case of Nepal, sandwiched between two most populous countries i.e. India and China. It was conjectured that the level of halogenated flame retardant (HFRs) in Nepalese air would be high because they have not been liable to control in Nepal; and henceforth there is more plausibility of HFRs to be available in a diverse array of goods and consumer products. This study therefore aims to measure the occurrence, spatial distributions and sources of 15 brominated- and 2 chlorinated-FRs in indoor air from four major cities of Nepal. The overall concentrations of HFRs ranged from 16.1 to 6750 pg/m3 (median 334 pg/m3). The total concentrations of novel brominated fire retardants (NBFRs) were 20 and 100 times (13.2-6270 pg/m3) higher than PBDEs (2.2-353 pg/m3) and DPs (0.67-129 pg/m3), respectively indicating much higher usages of NBFRs in Nepal. The level of ∑PBDEs in air is identified with utilization of wide variety of consumers products and building materials containing FRs in Nepalese houses, while higher concentration of BDE-209 were subject to emission from materials containing deca-BDE formulation. Significantly higher concentrations of DBDPE than BDE-209 in air demonstrated a move to more prominent use of DBDPE as alternative to BDE-209. The lower fanti ratios suggests the DP level in this study was essentially affected by the long range atmospheric transport from remote DP source instead of commercial products. The exposure to BDE-47, -99, -153, -209 and HBB via inhalation was 3-4 orders of magnitude lower than corresponding RfD values, suggesting insignificant risk to Nepalese population. However, other modes of human exposure might still be significant in Nepal.

  8. Flame retardant tris(1,3-dichloro-2-propylphosphate (TDCPP toxicity is attenuated by N-acetylcysteine in human kidney cells

    Directory of Open Access Journals (Sweden)

    David W. Killilea

    Full Text Available Prolonged exposure to the flame retardants found in many household products and building materials is associated with adverse developmental, reproductive, and carcinogenic consequences. While these compounds have been studied in numerous epidemiological and animal models, less is known about the effects of flame retardant exposure on cell function. This study evaluated the toxicity of the commonly used fire retardant tris(1,3-dichloro-2-propylphosphate (TDCPP in cell line derived from the kidney, a major tissue target of organohalogen toxicity. TDCPP inhibited cell growth at lower concentrations (IC50 27 μM, while cell viability and toxicity were affected at higher concentrations (IC50 171 μM and 168 μM, respectively. TDCPP inhibited protein synthesis and caused cell cycle arrest, but only at higher concentrations. Additionally, the antioxidant N-acetylcysteine (NAC reduced cell toxicity in cells treated with TDCPP, suggesting that exposure to TDCPP increased oxidative stress in the cells. In summary, these data show that low concentrations of TDCPP result in cytostasis in a kidney cell line, whereas higher concentrations induce cell toxicity. Furthermore, TDCPP toxicity can be attenuated by NAC, suggesting that antioxidants may be effective countermeasures to some organohalogen exposures. Keywords: flame retardant, cytostasis, cell toxicity, antioxidant, cell cycle

  9. Rapid identification of polystyrene foam wastes containing hexabromocyclododecane or its alternative polymeric brominated flame retardant by X-ray fluorescence spectroscopy.

    Science.gov (United States)

    Schlummer, Martin; Vogelsang, Jörg; Fiedler, Dominik; Gruber, Ludwig; Wolz, Gerd

    2015-07-01

    The brominated flame retardant hexabromocyclododecane (HBCDD) was added to Annex A of the list of persistent organic pollutants (POPs) of the Stockholm Convention. Thus, production and use of HBCDD will be banned, and the recycling of HBCDD-containing foam waste will be restricted. In reaction a special polymeric brominated flame retardant (PolyFR) was developed to replace HBCDD in expanded and extruded polystyrene foams for building and construction applications. A decision has to be made at some future time whether expanded and extruded polystyrene foam waste is to be subjected to incineration (with HBCDD) or to recycling (without HBCDD). Therefore, an appropriate and rapid field method is required to distinguish between foams containing HBCDD and foams free from HBCDD. Here we present a screening method for identifying HBCDD containing expanded and extruded polystyrene foams. The test principle is based on the fact that PolyFR (a brominated polymeric macromolecule) is not extractable whereas HBCDD (a low molecular weight substance) is extractable. Following rapid extraction of HBCDD the brominated flame retardant is identified and quantified via bromine analysis using a handheld X-ray fluorescence instrument. The method was applied successfully to 27 expanded and extruded polystyrene foam samples (foams and extruded polystyrene foam raw materials), which were provided without any information about the applied flame retardant. The presence of HBCDD was confirmed for all HBCDD-positive samples in the test. A robustness test revealed a high degree of correctness and a high repeatability for the test system: samples containing HBCDD and HBCDD-free samples were identified correctly with relative standard deviations of quantitative results below 14%. Moreover, X-ray fluorescence spectroscopy test results agree well with HBCDD determinations performed in a laboratory with a gas chromatograph coupled to a flame ionisation detector. © The Author(s) 2015.

  10. Functionalized layered double hydroxide-based epoxy nanocomposites with improved flame retardancy and mechanical properties

    OpenAIRE

    Ehsan Naderi Kalali; Xin Wanga; De-Yi Wang

    2015-01-01

    Functionalized layered double hydroxides (LDHs) based on a multi-modifier system composed of hydroxypropyl-sulfobutyl-beta-cyclodextrin sodium (sCD), dodecylbenzenesulfonate (DBS) and taurine (T) have been designed and fabricated in this paper, aiming at developing high performance fire retardant epoxy nanocomposites. In this multi-modifier system, sCD was utilized to improve the char yield, DBS was used to enlarge the inter-layer distance of LDH and T was used to enhance the interaction betw...

  11. Analysis of polybrominated diphenyl ethers and emerging halogenated and organophosphate flame retardants in human hair and nails.

    Science.gov (United States)

    Liu, Liang-Ying; Salamova, Amina; He, Ka; Hites, Ronald A

    2015-08-07

    A method for the digestion, extraction, fractionation, and analysis of three classes of flame retardants, including 36 polybrominated diphenyl ethers (PBDEs), 9 halogenated alternative flame retardants (AFRs), and 12 organophosphate esters (OPEs) in human hair and nail samples was developed. The method employed HNO3/H2O2 digestion, liquid-liquid extraction with (4:1 vol) hexane:dichloromethane, fractionation on a 6g column of 2.5% water deactivated Florisil, and analysis by gas chromatographic mass spectrometry. The accuracy and precision of the method was validated using spiked samples of 6 replicates for both hair and nail samples. The method validation results showed good accuracy and precision for all PBDEs except BDE-209, all AFRs except hexabromobenzene (HBB), and all of the 12 OPEs, with average recovery efficiencies>90% and relative standard deviations (RSDs)<10%. The average recovery efficiencies for HBB were between 60% and 86%, with RSDs<10%. BDE-209 had recovery efficiencies of 64% (RSD, 13%) for hair and 71% (RSD, 10%) for nail. This method was applied to analyze 5 human hair and 5 fingernail samples from the general student population at Indiana University Bloomington campus. BDE-47 and BDE-99 were the predominant PBDEs detected in both hair and nail samples, with a concentration range of 11-620 and 4.6-780ng/g (dry weight) in hair and 7.3-43 and 2.1-11ng/g in nails, respectively. Di-(2-ethylhexyl)-tetrabromophthalate (TBPH) and 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB) were detected in all the samples, with concentrations of 20-240 and 11-350ng/g in hair and <17-80 and <9.2-71ng/g in nails, respectively. Among the 12 OPEs analyzed, tris(2-chloroethyl)phosphate (TCEP), tris(1-chloro-2-propyl)phosphate (TCIPP), tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), and triphenyl phosphate (TPHP) were most often detected. The concentrations of these OPEs (summed together) were 1100-3900 and 380-18,000ng/g in hair and nails, respectively. These levels

  12. Occurrence and distribution of halogenated flame retardants in an urban watershed: Comparison to polychlorinated biphenyls and organochlorine pesticides.

    Science.gov (United States)

    Wang, Qian; Kelly, Barry C

    2017-12-01

    Due to restrictions on polybrominated diphenyl ethers (PBDEs), market demand for alternative flame retardants is projected to increase, worldwide. Information regarding the environmental behavior of these compounds is limited. The present study involved field measurements of several alternative halogenated flame retardants (HFRs), along with PBDEs and legacy persistent organic pollutants (POPs) in surface water, bottom sediments and suspended particulate matter (SPM) within a highly urbanized watershed in Singapore. Several alternative HFRs were detected in water and sediments. Dechlornane Plus stereoisomers (syn- and anti-DP) were detected in all samples, exhibiting relatively high concentrations in water, sediments and SPM. The maximum syn-DP concentrations in water, sediments and SPM were 24.30 ng/L, 2.48 ng/g dry wt. and 7774 ng/g dry wt., respectively. 1,2-Bis(2,4,6-tribromophenoxy) ethane (BTBPE), pentabromotoluene (PBT), hexabromobenzene (HxBBz) and tetrabromoethylcyclohexane (TBECH) were routinely detected. PBDE concentrations were relatively low and often non-detectable. Polychlorinated biphenyl (PCB) concentrations ranged from 0.017 to 8.37 ng/L in water, 9.86-27.92 ng/g dry wt. in SPM, and 6.48-212.3 ng/g dry wt. in sediments. Congener and isomer patterns suggested no recent inputs of PBDEs or dichlorodiphenyltrichloroethane (DDT). Rainfall was found to be an important factor influencing temporal and spatial patterns of DPs, BTBPE, PBDEs and some organochlorines in surface water. Land use index was found to be important for several organochlorines, but not HFRs. The observed sediment-water partitioning behavior of the studied HFRs and legacy POPs was highly dependent on chemical hydrophobicity. The data demonstrate that the studied HFRs have a relatively high affinity for SPM and bottom sediments. For example, the log K OC,OBS for TBECH, syn-DP and anti-DP and BTBPE in bottom sediments ranged between 8.1 and 9.6. The findings will aid future

  13. Legacy and emerging organophosphοrus flame retardants in car dust from Greece: Implications for human exposure.

    Science.gov (United States)

    Christia, Christina; Poma, Giulia; Besis, Athanasios; Samara, Constantini; Covaci, Adrian

    2018-04-01

    Organophosphorus flame retardants (PFRs) and emerging PFRs (ePFRs) are two groups of compounds used as replacements for brominated flame retardants (BFRs). They have already been detected in indoor dust (mainly in homes and offices). To date, few studies investigated the occurrence of FRs in car dust and the information of possible health risks is still limited. The present study reports on the investigation of the levels and profiles of eight target PFRs: tris(2-ethylhexyl) phosphate (TEHP), tris(2-chloroethyl) phosphate (TCEP), tris(2-butoxyethyl) phosphate (TBEP), triphenyl phosphate (TPHP), 2-ethylhexyl diphenyl phosphate (EHDPHP), tris(1-chloro-2-propyl) phosphate (TCIPP), tri cresyl phosphate (TCP), tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) and four target ePFRs; 2,2-bis(chloromethyl)propane-1,3-diyltetrakis(2-chloroethyl)bisphosphate (V6), isodecyl diphenyl phosphate (iDDPHP), resorcinol bis(diphenylphosphate) (RDP) and bisphenol A-bis(diphenyl phosphate) (BDP) in car dust from Greece. The samples were collected from the interior of 25 private cars in Thessaloniki, Greece, with different years of manufacture (1997-2015) and continents of origin. After ultrasonic extraction and Florisil fractionation, the PFR analysis was carried out by GC-EI/MS, whereas the ePFRs were analyzed by LC-MS/MS. Levels of Σ 8 PFRs varied from 2000 to 190,000 ng g -1 , with mean and median concentrations of 20,000 and 11,500 ng g -1 , respectively. The concentrations of Σ 4 ePFRs ranged from 44 to 8700 ng g -1 , with mean and median values at 1100 and 190 ng g -1 , respectively. Estimations of human exposure showed that toddlers are more exposed than adults to both PFRs and ePFRs. Yet, the intake via dust ingestion and dermal absorption was several orders of magnitude lower than the corresponding reference doses. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Paternal urinary concentrations of organophosphate flame retardant metabolites, fertility measures, and pregnancy outcomes among couples undergoing in vitro fertilization.

    Science.gov (United States)

    Carignan, Courtney C; Mínguez-Alarcón, Lidia; Williams, Paige L; Meeker, John D; Stapleton, Heather M; Butt, Craig M; Toth, Thomas L; Ford, Jennifer B; Hauser, Russ

    2018-02-01

    Use of organophosphate flame retardants (PFRs) has increased over the past decade following the phase out of some brominated flame retardants, leading to increased human exposure. We recently reported that increasing maternal PFR exposure is associated with poorer pregnancy outcomes among women from a fertility clinic. Because a small epidemiologic study previously reported an inverse association between male PFR exposures and sperm motility, we sought to examine associations of paternal urinary concentrations of PFR metabolites and their partner's pregnancy outcomes. This analysis included 201 couples enrolled in the Environment and Reproductive Health (EARTH) prospective cohort study (2005-2015) who provided one or two urine samples per IVF cycle. In both the male and female partner, we measured five urinary PFR metabolites [bis(1,3-dichloro-2-propyl) phosphate (BDCIPP), diphenyl phosphate (DPHP), isopropylphenyl phenyl phosphate (ip-PPP), tert-butylphenyl phenyl phosphate (tb-PPP) and bis(1-chloro-2-propyl) phosphate (BCIPP)] using negative electrospray ionization liquid chromatography tandem mass spectrometry (LC-MS/MS). The sum of the molar concentrations of the urinary PFR metabolites was calculated. We used multivariable generalized linear mixed models to evaluate the association of urinary concentrations of paternal PFR metabolites with IVF outcomes, accounting for multiple in vitro fertilization (IVF) cycles per couple. Models were adjusted for year of IVF treatment cycle, primary infertility diagnosis, and maternal urinary PFR metabolites as well as paternal and maternal age, body mass index, and race/ethnicity. Detection rates were high for paternal urinary concentrations of BDCIPP (84%), DPHP (87%) and ip-PPP (76%) but low for tb-PPP (12%) and zero for BCIPP (0%). We observed a significant 12% decline in the proportion of fertilized oocytes from the first to second quartile of male urinary ΣPFR and a 47% decline in the number of best quality embryos

  15. Analysis of monomeric and oligomeric organophosphorus flame retardants in fish muscle tissues using liquid chromatography–electrospray ionization tandem mass spectrometry: Application to Nile tilapia (Oreochromis niloticus) from an e-waste processing area in northern Vietnam

    OpenAIRE

    Matsukami, Hidenori; Suzuki, Go; Tue, Nguyen Minh; Tuyen, Le Huu; Viet, Pham Hung; Takahashi, Shin; Tanabe, Shinsuke; Takigami, Hidetaka

    2016-01-01

    Using electrospray ionization tandem mass spectrometry combined with liquid chromatography (LC), a novel analytical method was developed to quantify eight monomeric organophosphorus flame retardants (m-PFRs) and three oligomeric organophosphorus flame retardants (o-PFRs) in fish muscle samples. The optimization and validation experiments indicate that the developed method can determine accurately the concentrations of analytes in fish muscle samples. The recoveries of analytes in fish muscle ...

  16. Determination of halogenated flame retardants by GC-API-MS/MS and GC-EI-MS: a multi-compound multi-matrix method.

    Science.gov (United States)

    Neugebauer, Frank; Dreyer, Annekatrin; Lohmann, Nina; Koschorreck, Jan

    2018-02-01

    The extensive application of halogenated flame retardants has led to their widespread distribution in the environment. Recently, concerns emerged regarding their potential persistence, (bio)accumulation, and/or toxicity. Particularly halogenated flame retardants based on norbornene structures, like Dechlorane Plus as well as other brominated PBDE replacements, generically called emerging, novel, or alternative flame retardants, are in the focus of interest. A comprehensive analytical method for the determination of 21 halogenated flame retardants (HFRs) of different substance classes (dechloranes, brominated aromates, brominated ethers, cyclic BFR) in a broad variety of matrices (tree leaves, fish fillet, birds eggs, suspended particles) was developed in order to assess their environmental levels as well as temporal trends, especially for the use within environmental specimen banks (ESBs). In addition to the alternative HFRs, a set of 24 PBDEs were measured in the same samples, however using GC-EI-MS for detection. Samples were extracted using accelerated solvent extraction (ASE) with dichloromethane:hexane (exception: soxhlet extraction for suspended particles) followed by a multi column clean-up. Quantification was performed by API-GC-MS/MS as a modern, gentle, and sensitive technique for simultaneous detection of compounds throughout a wide range of masses and fragmentation characteristics (exception: PBDE detection using GC-EI-MS). With the exception of BDE 209, instrumental precisions of target compounds ranged from 1% to 16 % (at levels of 2 pg injection -1 for HFR, 20 pg injection -1 for DBDPE, 7-36 pg injection -1 for PBDEs). Interday precisions of the entire analytical method including extraction and clean-up were mostly below 25% for all validation matrices at spiked levels of 100 pg sample -1 for HFR (DBDPE: 1000 pg sample -1 ) and 1200-6000 pg sample -1 for PBDEs. The majority of analytes were investigated with expanded measurement uncertainties of less

  17. Flame retardants and organochlorines in indoor dust from several e-waste recycling sites in South China: composition variations and implications for human exposure.

    Science.gov (United States)

    Zheng, Xiaobo; Xu, Fuchao; Chen, Kehui; Zeng, Yanhong; Luo, Xiaojun; Chen, Shejun; Mai, Bixian; Covaci, Adrian

    2015-05-01

    Several classes of flame retardants, such as polybrominated diphenyl ethers (PBDEs), novel brominated flame retardants (NBFRs), dechlorane plus (DPs), and organophosphate flame retardants (PFRs), together with polychlorinated biphenyls (PCBs) were measured in indoor dust from five villages located in three e-waste recycling regions in Guangdong Province, South China. The medians of PBDEs, NBFRs, and PFRs in dust in five sites ranged from 685-67,500, 1460-50,010, and 2180-29,000ng/g, respectively. These concentrations were much higher than the medians of PCBs (52-2900ng/g). BDE 209 and decabromodiphenyl ethane (DBDPE) were the two major halogen flame retardants in dust, while tris-(1-chloro-2-propyl) phosphate (TCIPP) and triphenyl phosphate (TPHP) were the major PFRs. Principle component analysis revealed the different pollutant patterns among different sites. The estimated median human exposures of PBDEs, NBFRs, PFRs, and PCBs via dust ingestion were 1.1-24.1, 0.73-20.3, 1.36-23.5, and 0.04-0.93ng/kgbw/day for adults, and 16.2-352, 10.7-296, 19.9-343, 0.05-0.61, 0.65-13.6ng/kgbw/day for toddlers, respectively. Residents from Site 5 had the highest exposure (95 percentile levels and high dust ingestion for toddlers) of PBDEs (3920ng/kgbw/day), NBFRs (3200ng/kgbw/day), and PFRs (5280ng/kgbw/day). More attention should be paid to the contamination with NBFRs and PFRs, instead of PCBs, in these e-waste recycling regions, and local public health threat from PBDE alternatives should remain of concern. To the best of our knowledge, this is the first study on human exposure assessment of PFRs at e-waste sites. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. One-step fabrication of novel superhydrophobic and superoleophilic sponge with outstanding absorbency and flame-retardancy for the selective removal of oily organic solvent from water

    Science.gov (United States)

    Xiang, Yuqian; Pang, Youyou; Jiang, Xiaomei; Huang, Jie; Xi, Fengna; Liu, Jiyang

    2018-01-01

    Absorbent materials integrated with superhydrophobicity, superoleophilicity and flame-retardancy are highly desired in the adsorption/removal of flammable oils/organic compounds as well as reducing the risk of fire and explosion. Here, one-step fabrication of novel superhydrophobic and superoleophilic sponge with outstanding absorbency and flame-retardancy was presented. Using raw melamine (ME) sponge as the supporting matrix, the formation of polydopamine (PDA) nanoaggregates via in-situ self-polymerization of high-concentrated dopamine and the covalent grafting of hydrophobic n-dodecylthiol (DT) onto PDA were combined in a feasible alkaline water/ethanol medium. As investigated by scanning electron microscopy (SEM) and X-ray energy-dispersive spectroscopy (EDS), the as-prepared ME/PDA/DT sponge possessed hierarchical structure with submicron PDA nanoaggregates containing DT motif (low surface energy) on 3D interconnected porous network. It exhibited superhydrophobic (water contact angle 157.7°) and superoleophilic (oily/organic solvent contact angle 0° properties. Owing to the highly porous structure, superhydrophobic property, chemical and mechanical stability, the ME/PDA/DT sponge exhibited outstanding absorbency properties of oily organic solvents including fast absorption kinetics, high absorption capacity, and easy reusability. Also, the ME/PDA/DT sponge could be used for one-line continuous organic solvent/water separation. More interestingly, the ME/PDA/DT sponge demonstrated improved flame-retardant property as compared to the intrinsic flame-retardant nature of the raw melamine sponge. Consequently, the risk of fire and explosion was expected to reduce when the fabricated sponge was used as an absorbent for flammable oils and organic compounds. The ease of the one-step superhydrophobic/superoleophilic modification and the promising feature of the obtained materials exhibit great potential for application in oils/organic solvents clean-up.

  19. A single α-cobalt hydroxide/sodium alginate bilayer layer-by-layer assembly for conferring flame retardancy to flexible polyurethane foams

    Energy Technology Data Exchange (ETDEWEB)

    Mu, Xiaowei [State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230026 (China); Yuan, Bihe [School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070 (China); Pan, Ying; Feng, Xiaming; Duan, Lijin [State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230026 (China); Zong, Ruowen, E-mail: zongrw@ustc.edu.cn [State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230026 (China); Hu, Yuan, E-mail: yuanhu@ustc.edu.cn [State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230026 (China); National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230026 (China)

    2017-04-15

    A layer-by-layer (LBL) assembly coating composed of α-cobalt hydroxide (α-Co(OH){sub 2}) and sodium alginate (SA) is deposited on flexible polyurethane (FPU) foam to reduce its flammability. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) are employed to prove the LBL assembly process. It is obvious from SEM results that a uniform and rough coating is deposited on FPU foam compared with that of untreated one. The peak intensity of methylene of SA in FITR spectra and typical (003) diffraction peak of α-Co(OH){sub 2} nanosheets at 11.0° in XRD patterns increases gradually with increment of bilayer number. Combustion behavior and toxicity suppression property of samples are characterized by cone calorimeter (under an irradiance of 35 kW m{sup −2}) and Thermogravimetry/Fourier transform infrared spectroscopy. The one and two bilayers (BL) coating on FPU foam can achieve excellent flame retardancy. Compared with untreated sample, the peak heat release rate of the coated FPU foam containing only one BL coating is reduced by 58.7%. The content of gaseous toxic substances during pyrolysis of FPU foam deposited with a single bilayer coating, such as CO and NCO-containing compounds, are reduced by 20.0% and 9.2%, respectively. Besides, the flame retardant mechanism of the coated FPU foam is also revealed. - Highlights: • The α-Co(OH){sub 2} nanosheets are firstly employed in LBL assembly. • A single α-cobalt hydroxide/sodium alginate bilayer LBL assembly for conferring excellent flame retardancy to FPU foam. • The flame retardant mechanism of LBL assembly FPU foam is displayed.

  20. The flame retardants tetrabromobisphenol A and tetrabromobisphenol A-bisallylether suppress the induction of interleukin-2 receptor α chain (CD25) in murine splenocytes

    International Nuclear Information System (INIS)

    Pullen, Sabine; Boecker, Ronald; Tiegs, Gisa

    2003-01-01

    Polybrominated flame retardants (PBF) are frequently used additives in electronical equipment. They are ubiquitous environmental contaminants which bioaccumulate with several health effects for humans and the environment. This study investigated immunotoxic effects of the PBF tetrabromobisphenol A (TBBP A), tetrabromobisphenol A-bisallylether (TBBP A-AE), tetrabromobisphenol A-bis-(2,3-dibromopropyl-ether) (TBBP A-PE), decabromodiphenylether (DBDE), and 2,4,6-tribromophenol (TBP) in vitro. The structurally related polychlorinated aromatic hydrocarbon 3,4,3',4'-tetrachlorobiphenyl (PCB77) and dioxins mediate their immunotoxicity via the Ah-receptor gene complex. A highly relevant function of the Ah receptor, the induction of CYP 1A1 in hepatocytes of C57BL/6 mice by the established inducers 3-methylcholanthrene (MC) and PCB77 was compared to the effect of PBF by measurement of ethoxyresorufin-o-deethylase (EROD) activity. The PBF did not show any induction of CYP 1A1, while EROD activity of hepatocytes exposed to MC and PCB77 was induced 10.8- and 8.7-fold, respectively. To investigate immunotoxic effects of the flame retardants, splenocytes of C57BL/6 mice were incubated with subtoxic doses of the flame retardants and PCB77 and activated by concanavalin A (Con A). The flame retardants TBBP A and TBBP A-AE significantly inhibited the expression of interleukin-2 receptor α chain (CD25) in contrast to TBBP A-PE, DBDE, TBP, and PCB77 as shown by immunohistochemistry and quantitative analysis by laser scanning cytometry. None of the substances had any effect on the Con A-induced production of cytokines. Hence, TBBP A and TBBP A-AE may act as immunotoxic compounds by specifically inhibiting the expression of CD25

  1. A novel and facile strategy for highly flame retardant polymer foam composite materials: Transforming silicone resin coating into silica self-extinguishing layer.

    Science.gov (United States)

    Wu, Qian; Zhang, Qian; Zhao, Li; Li, Shi-Neng; Wu, Lian-Bin; Jiang, Jian-Xiong; Tang, Long-Cheng

    2017-08-15

    In this study, a novel strategy was developed to fabricate highly flame retardant polymer foam composite materials coated by synthesized silicone resin (SiR) polymer via a facile dip-coating processing. Applying the SiR polymer coating, the mechanical property and thermal stability of SiR-coated polymer foam (PSiR) composites are greatly enhanced without significantly altering their structure and morphology. The minimum oxygen concentration to support the combustion of foam materials is greatly increased, i.e. from LOI 14.6% for pure foam to LOI 26-29% for the PSiR composites studied. Especially, adjusting pendant group to SiOSi group ratio (R/Si ratio) of SiRs produces highly flame retardant PSiR composites with low smoke toxicity. Cone calorimetry results demonstrate that 44-68% reduction in the peak heat release rate for the PSiR composites containing different R/Si ratios over pure foam is achieved by the presence of appropriate SiR coating. Digital and SEM images of post-burn chars indicate that the SiR polymer coating can be transformed into silica self-extinguishing porous layer as effective inorganic barrier effect, thus preserving the polymer foam structure from fire. Our results show that the SiR dip-coating technique is a promising strategy for producing flame retardant polymer foam composite materials with improved mechanical properties. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Spatial distribution and implications to sources of halogenated flame retardants in riverine sediments of Taizhou, an intense e-waste recycling area in eastern China.

    Science.gov (United States)

    Zhou, Shanshan; Fu, Jie; He, Huan; Fu, Jianjie; Tang, Qiaozhi; Dong, Minfeng; Pan, Yongqiang; Li, An; Liu, Weiping; Zhang, Limin

    2017-10-01

    Concentrations and spatial distribution pattern of organohalogen flame retardants were investigated in the riverine surface sediments from Taizhou, an intensive e-waste recycling region in China. The analytes were syn- and anti- Dechlorane Plus (DP), Dechloranes 602, 603, and 604, a DP monoadduct, two dechlorinated DPs and 8 congeners of polybrominated diphenyl ethers (PBDEs). The concentrations of Σ 8 PBDEs, ΣDP, ΣDec600s, and ΣDP-degradates ranged from recycling facilities. Such patterns were largely shared by Dec602 and dechlorinated DP, although their concentration levels were much lower. These major flame retardants significantly correlate with each other, and cluster together in the loading plot of principle component analysis. In contrast, most non-deca PBDE congeners do not correlate with DPs. Dec604 stood out having distinctly different spatial distribution pattern, which could be linked to historical use of mirex. Organic matter content of the sediment was not the dominant factor in determining the spatial pattern of pollution by halogenated flame retardants in the rivers of this study. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Fish DNA-modified clays: Towards highly flame retardant polymer nanocomposite with improved interfacial and mechanical performance

    Science.gov (United States)

    Zabihi, Omid; Ahmadi, Mojtaba; Khayyam, Hamid; Naebe, Minoo

    2016-12-01

    Deoxyribonucleic Acid (DNA) has been recently found to be an efficient renewable and environmentally-friendly flame retardant. In this work, for the first time, we have used waste DNA from fishing industry to modify clay structure in order to increase the clay interactions with epoxy resin and take benefit of its additional thermal property effect on thermo-physical properties of epoxy-clay nanocomposites. Intercalation of DNA within the clay layers was accomplished in a one-step approach confirmed by FT-IR, XPS, TGA, and XRD analyses, indicating that d-space of clay layers was expanded from ~1.2 nm for pristine clay to ~1.9 nm for clay modified with DNA (d-clay). Compared to epoxy nanocomposite containing 2.5%wt of Nanomer I.28E organoclay (m-clay), it was found that at 2.5%wt d-clay loading, significant enhancements of ~14%, ~6% and ~26% in tensile strength, tensile modulus, and fracture toughness of epoxy nanocomposite can be achieved, respectively. Effect of DNA as clay modifier on thermal performance of epoxy nanocomposite containing 2.5%wt d-clay was evaluated using TGA and cone calorimetry analysis, revealing significant decreases of ~4000 kJ/m2 and ~78 kW/m2 in total heat release and peak of heat release rate, respectively, in comparison to that containing 2.5%wt of m-clay.

  4. Occurrence of classic and emerging halogenated flame retardants in sediment and sludge from Ebro and Llobregat river basins (Spain).

    Science.gov (United States)

    Barón, Enrique; Santín, Giselle; Eljarrat, Ethel; Barceló, Damià

    2014-01-30

    Classic (polybromodiphenyl ethers, PBDEs) and emerging halogenated flame retardants such as hexabromobenzene (HBB), pentabromoetilbenzene (PBEB), decabromodiphenyl ethane (DBDPE), Dechlorane 602 (Dec 602), Dechlorane 603 (Dec 603), Dechlorane 604 (Dec 604) and Dechlorane plus (DP) were analyzed in 33 sediments and 7 sludges from two Iberian river basins, Ebro and Llobregat. In sediment samples, PBDE levels ranged between nd and 44.3ng/g dw with BDE-209 being the most abundant congener. Levels of DBDPE and halogenated norbornenes ranged between nd and 31.5ng/g dw and between nq and 3.74ng/g dw, respectively. This is the first study to report halogenated norbornene levels in sediment samples from Spain. PBDE, DBDPE and halogenated norbornene levels in sludge ranged from 13 to 340, nq to 124 and 2.7 to 19ng/g dw, respectively. HBB and PBEB were not detected in any sample. Levels of classic and emerging HFRs were compared. Our results suggest that DBDPE is the most frequently used compound to replace BDE-209, whereas the use of halogenated norbornenes is still low. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Bioaccumulation of polybrominated diphenyl ethers and several alternative halogenated flame retardants in a small herbivorous food chain.

    Science.gov (United States)

    She, Ya-Zhe; Wu, Jiang-Ping; Zhang, Ying; Peng, Ying; Mo, Ling; Luo, Xiao-Jun; Mai, Bi-Xian

    2013-03-01

    Little is known about the bioaccumulation behavior of polybrominated diphenyl ethers (PBDEs) and other halogenated flame retardants (HFRs) in plants and in herbivores. In the present study, PBDEs and several alternative HFRs (AHFRs) were examined in a small herbivorous food chain (paddy soils-rice plant-apple snails) from an electronic waste recycling site in South China. Mean concentrations of total PBDEs were 40.5, 1.81, and 5.54 ng/g dry weight in the soils, rice plant, and apple snails, respectively. Levels of total AHFRs in the samples were comparable to or even higher than those of PBDEs. The calculated plant to soil concentration ratios for most AHFRs (0.05-3.40) were higher than those for PBDEs (0.02-0.23), indicating the greater bioavailability of the AHFRs in the rice plant. All PBDE congeners and Dechlorane Plus (DP) isomers were biomagnified from the rice plant to apple snails, with mean biomagnification factors (BMFs) of 1.1-5.0. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Halogenated flame retardants (HFRs) in surface sediment from the Pearl River Delta region and Mirs Bay, South China.

    Science.gov (United States)

    Zhu, Bingqing; Lam, James C W; Lam, Paul K S

    2017-10-24

    A total of 43 surface sediment collected from rivers and the estuaries in the Pearl River Delta (PRD) region and Mirs Bay from the South China were analyzed for twelve halogenated flame retardants (HFRs) including polybrominated diphenyl ethers (PBDEs) using liquid chromatography-tandem mass spectrometer system. Their levels, spacial distribution, congener profiles and possible sources were investigated. Decabromodiphenyl ethane (DBDPE) was the predominant contaminant (1.520-1714ng/g dw) in the study area exceeding those of PBDEs (8.090-595.8ng/g dw), implying that DBDPE has been the predominant HFR products in this region in recent years in addition to PBDEs. Whereas the ratio of [DBDPE/BDE 209] varied among samples, this is indicative of different usage patterns of HFRs between PRD region and Mirs Bay. The PBDEs congener was dominated by BDE 209, with the average value accounting for 86.8% of the total PBDE in the sediment samples. Copyright © 2017. Published by Elsevier Ltd.

  7. Atmospheric concentrations of halogenated flame retardants at two remote locations: the Canadian High Arctic and the Tibetan Plateau.

    Science.gov (United States)

    Xiao, Hang; Shen, Li; Su, Yushan; Barresi, Enzo; Dejong, Maryl; Hung, Hayley; Lei, Ying-Duan; Wania, Frank; Reiner, Eric J; Sverko, Ed; Kang, Shi-Chang

    2012-02-01

    Atmospheric concentrations of halogenated flame retardants (FRs) were monitored for approximately one year at two remote stations, namely Nam Co on the Tibetan Plateau and Alert in the Canadian High Arctic. BDE-47 and 99 were the dominant polybrominated diphenyl ether (PBDE) congeners at both sites. Atmospheric PBDE concentrations in Nam Co were generally lower than those at Alert. While significant seasonal variations were observed for PBDEs at Alert, the FR concentrations at Nam Co showed no significant seasonality, even though air masses originated from distinctly different regions during different seasons. This suggests that FRs in Tibet do not have regional sources, but are reflective of truly global background contamination. Three new FRs, namely 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), 2-ethyl-1-hexyl-2,3,4,5-tetrabromobenzoate (EHTeBB) and bis(2-ethyl-1-hexyl)tetrabromophthalate (TBPH) were detected at relatively high concentrations at both sites. This is the first report of these FRs in the remote global atmosphere and suggests significant potential for long-range atmospheric transport. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  8. Occurrence of PBDEs and alternative halogenated flame retardants in sewage sludge from the industrial city of Guangzhou, China.

    Science.gov (United States)

    Wu, Qihang; Li, Haiyan; Kuo, Dave T F; Chen, Shejun; Mai, Bixian; Li, Huosheng; Liu, Zhineng; Deng, Mingjun; Zhang, Haozhi; Hu, Xiaodong; Geng, Xinhua; Chen, Yongheng

    2017-01-01

    This study investigated the prevalence and abundance of halogenated flame retardants (HFRs) in sludge samples from 5 sewage treatment plants in Guangzhou, China. Detection of 18 polybrominated diphenyl ethers (PBDEs), 9 alternative HFRs including Dechlorane Plus (DP), brominated alkylbenzenes, and polybrominated biphenyls, and 2 related degradation products was conducted. Decabromodiphenyl ether (BDE 209) and decabromodiphenyl ethane (DBDPE) were the dominant HFRs, with concentrations ranging from 200 to 2150 ng/g and 680-27,400 ng/g, respectively. The DBDPE detected was the highest level reported so far, exceeding those previously reported by 10-100 times. PBDEs were surpassed as the dominant HFRs in sewage sludge, with mean DBDPE/BDE 209 ratio exceeding 2 in all samples. The review of earlier surveys reveals that DBDPE level was surging while BDE 209 was declining. Annual emissions of BDE 209, DP, and DBDPE were estimated to be 227.9, 10.5, and 979.3 kg/yr, respectively. Although ecological risks assessment suggested low risks for the examined sludge, the key environmental properties and transformation pathways of alternative HFRs remain largely unknown. These findings prompt for further investigations on alternative HFR and sustainable management practices for HFR-laden biosolids. The HFR emission pattern revealed in this study is likely representative of other similarly industrialized regions in the post-PBDE era. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Investigating endocrine and physiological parameters of captive American kestrels exposed by diet to selected organophosphate flame retardants.

    Science.gov (United States)

    Fernie, Kimberly J; Palace, Vince; Peters, Lisa E; Basu, Nil; Letcher, Robert J; Karouna-Renier, Natalie K; Schultz, Sandra L; Lazarus, Rebecca S; Rattner, Barnett A

    2015-06-16

    Organophosphate triesters are high production volume additive flame retardants (OPFRs) and plasticizers. Shown to accumulate in abiotic and biotic environmental compartments, little is known about the risks they pose. Captive adult male American kestrels (Falco sparverius) were fed the same dose (22 ng OPFR/g kestrel/d) daily (21 d) of tris(2-butoxyethyl) phosphate (TBOEP), tris(2-chloroethyl) phosphate (TCEP), tris(2-chloroisopropyl) phosphate (TCIPP), or tris(1,2-dichloro-2-propyl) phosphate (TDCIPP). Concentrations were undetected in tissues (renal, hepatic), suggesting rapid metabolism. There were no changes in glutathione status, indicators of hepatic oxidative status, or the cholinergic system (i.e., cerebrum, plasma cholinesterases; cerebrum muscarinic, nicotinic receptors). Modest changes occurred in hepatocyte integrity and function (clinical chemistry). Significant effects on plasma free triiodothyronine (FT3) concentrations occurred with exposure to TBOEP, TCEP, TCIPP, and TDCIPP; TBOEP and TCEP had additional overall effects on free thyroxine (FT4), whereas TDCIPP also influenced total thyroxine (TT4). Relative increases (32%-96%) in circulating FT3, TT3, FT4, and/or TT4 were variable with each OPFR at 7 d exposure, but limited thereafter, which was likely maintained through decreased thyroid gland activity and increased hepatic deiodinase activity. The observed physiological and endocrine effects occurred at environmentally relevant concentrations and suggest parent OPFRs or metabolites may have been present despite rapid degradation.

  10. Brominated flame retardants in mangrove sediments of the Pearl River Estuary, South China: spatial distribution, temporal trend and mass inventory.

    Science.gov (United States)

    Zhang, Zai-Wang; Sun, Yu-Xin; Sun, Kai-Feng; Xu, Xiang-Rong; Yu, Shen; Zheng, Tian-Ling; Luo, Xiao-Jun; Tian, Yun; Hu, Yong-Xia; Diao, Zeng-Hui; Mai, Bi-Xian

    2015-03-01

    Sediments were collected from three mangrove wetlands in the Pearl River Estuary (PRE) of South China to investigate spatial and temporal distributions of polybrominated diphenyl ethers (PBDEs), decabromodiphenyl ethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE). Concentrations of ΣPBDEs, DBDPE and BTBPE in mangrove sediments of the PRE ranged from 1.25-206, 0.364-34.9, and not detected-0.794 ng g(-1) dry weight, respectively. The highest concentrations of ΣPBDEs, DBDPE and BTBPE were found at the mangrove wetland from Shenzhen, followed by Zhuhai and Guangzhou, showing the dependence on the proximity to urban areas. PBDEs were the predominant brominated flame retardants (BFRs) in mangrove sediments. The concentrations of ΣPBDEs, DBDPE and BTBPE in sediment cores showed an increasing trend from the bottom to top layers, reflecting the increasing usage of these BFRs. The inventories of ΣPBDEs, DBDPE and BTBPE in mangrove sediments were 1962, 245, and 4.10 ng cm(-2), respectively. This is the first study to report the occurrence of DBDPE and BTBPE in mangrove ecosystems. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Preparation and Flame Retardant and Smoke Suppression Properties of Bamboo-Wood Hybrid Scrimber Filled with Calcium and Magnesium Nanoparticles

    Directory of Open Access Journals (Sweden)

    Bin Fu

    2014-01-01

    Full Text Available The physical and mechanical properties of bamboo-wood hybrid scrimber filled with different loadings of nanoparticles were studied. The effects of nanoparticles on flame retardant and smoke suppression properties of bamboo-wood hybrid scrimber were studied by means of thermogravimetric analysis (TGA, cone calorimeter (CONE, and scanning electron microscope (SEM. The results showed that the physical and mechanical properties of bamboo-wood hybrid scrimber were improved by adding a moderate loading of nanoparticles; the optimal loading of nanoparticles was 10%. The heat transfer in bamboo-wood hybrid scrimber was prevented and the escaping channel of combustible gas was blocked by the uniformly filling effect of nanoparticles. The gas concentration was diluted by the noncombustible gas produced by pyrolysis of nanoparticles; the combustion chain reaction was suppressed by highly reactive free radicals produced by pyrolysis of nanoparticles. The residual mass of bamboo-wood hybrid scrimber filled with nanoparticles in thermogravimetric (TG curve at 900 s and burned by method of cone calorimeter (CONE at 600 s was increased compared to that of untreated one, which showed that inorganic mineral powder has the effect of catalytic charring.

  12. Flame retardancy of polyamide 6 hybrid fibers: Combined effects of α-zirconium phosphate and ammonium sulfamate

    Directory of Open Access Journals (Sweden)

    Hengxue Xiang

    2017-06-01

    Full Text Available Synergistic effect between α-zirconium phosphate (α-ZrP and ammonium sulfamate (AS for enhanced flame retardant properties of Polyamide 6 (PA6 was investigated by using oxygen index instrument, cone calorimeter, thermogravimetric analyzer (TGA, Instron universal test machine and scanning electron microscopy (SEM. PA6/AS/α-ZrP ternary hybrid materials with various contents of α-ZrP and AS were fabricated by melt-mixing method. The result from flammability indicated that the Limiting oxygen index (LOI and Underwriters Laboratories-94 (UL-94 rating of PA6/AS/α-ZrP were significantly accelerated under the coordinating function of α-ZrP and AS. Moreover, the thermal stability for PA6/AS/α-ZrP studied by TGA also demonstrated this synergistic effect between α-ZrP and AS on the heat resistance. The effects of the usage amount of α-ZrP and AS on mechanical properties were analyzed by using uniaxial tensile test. It was found that the addition of AS provided negative effects on the tensile strength of PA6/AS/α-ZrP, however, the adverse trends that mentioned above could be overcome by using the well dispersed α-ZrP.

  13. Brominated flame retardants and perfluorinated chemicals, two groups of persistent contaminants in Belgian human blood and milk

    Energy Technology Data Exchange (ETDEWEB)

    Roosens, Laurence [Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk (Belgium); D' Hollander, Wendy; Bervoets, Lieven [Laboratory for Ecophysiology, Biochemistry and Toxicology, Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium); Reynders, Hans; Van Campenhout, Karen [Environment and Health Unit, Department of Environment, Nature and Energy, Flemish Government - Koning Albert II-laan 20, Bus 8, 1000 Brussels (Belgium); Cornelis, Christa; Van Den Heuvel, Rosette; Koppen, Gudrun [Unit Environmental Risk and Health, Flemish Institute of Technological Research (VITO), Boeretang 200, 2400 Mol (Belgium); Covaci, Adrian, E-mail: adrian.covaci@ua.ac.b [Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk (Belgium); Laboratory for Ecophysiology, Biochemistry and Toxicology, Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium)

    2010-08-15

    We assessed the exposure of the Flemish population to brominated flame retardants (BFRs) and perfluorinated compounds (PFCs) by analysis of pooled cord blood, adolescent and adult serum, and human milk. Levels of polybrominated diphenyl ethers (PBDEs) in blood (range 1.6-6.5 ng/g lipid weight, lw) and milk (range 2.0-6.4 ng/g lw) agreed with European data. Hexabromocyclododecane ranged between <2.1-5.7 ng/g lw in milk. Perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) dominated in blood and ranged between 1 and 171 ng/mL and <0.9-9.5 ng/mL, respectively. Total PFC levels in milk ranged between <0.5-29 ng/mL. A significant increase in PBDE concentrations was detected from newborns (median 2.1) to the adolescents and adults (medians 3.8 and 4.6 ng/g lw, respectively). An identical trend was observed for PFOS, but not for PFOA. We estimated that newborn exposure to BFRs and PFCs occurs predominantly post-natally, whereas placental transfer has a minor impact on the body burden. - The exposure to BFRs and PFCs of general Flemish population has been assessed throughout several age groups.

  14. Terminal elimination half-lives of the brominated flame retardants TBBPA, HBCD, and lower brominated PBDEs in humans

    Energy Technology Data Exchange (ETDEWEB)

    Geyer, H.J.; Schramm, K.W.; Feicht, E.A.; Fried, K.W.; Henkelmann, B.; Lenoir, D. [GSF-National Research Center, Institute of Ecological Chemistry, Neuherberg (Germany); Darnerud, P.O.; Aune, M. [Swedish National Food Administration, Uppsala (Sweden); Schmid, P. [Swiss Federal Laboratories for Materials Testing and Research, Laboratory of Organic Chemistry, EMPA Duebendorf (Switzerland); McDonald, T.A. [Office of Environmental Health Assessment, California EPA, Oakland, CA (United States)

    2004-09-15

    Brominated flame retardants (BFRs) are widely used in polymers and textiles and applied in electronic equipment, construction materials, and furniture for the purpose of fire prevention. BFRs with the highest production volume are tetrabromobisphenol A (TBBPA), 1,2,5,6,9,10- hexabromocyclododecanes (HBCDs: {alpha}-HBCD + {beta}-HBCD + {gamma}-HBCD), and polybrominated diphenyl ethers (PBDEs). Several BFRs are highly lipophilic persistent organic pollutants (POPs) which have been identified in the aquatic and terrestrial environment including wildlife and humans. In exposed organisms including humans toxic effects, bioaccumulation, metabolism, and pharmacokinetics (especially half-life t{sub 1/2}) are important criterions in the hazard assessment. The aim of the present study was to estimate the terminal elimination half-lives (t{sub 1/2H}) of the main BFRs from the whole body (also named body-burden half-life) and/or from the adipose tissue (fat) of adult humans. The t{sub 1/2H} data for the following BFRs were evaluated: TBBPA, HBCD, 2,2',4,4'- tetrabromodiphenyl ether (BDE-47), 2,2',4,4',5-pentaBDE (BDE-99), 2,2',4,4',6-pentaBDE (BDE- 100), 2,2',4,4',5,5'-hexaBDE (BDE-153), and 2,2',4,4',5,6-hexaBDE (BDE-154).

  15. Determination of polyparameter linear free energy relationship (pp-LFER) substance descriptors for established and alternative flame retardants.

    Science.gov (United States)

    Stenzel, Angelika; Goss, Kai-Uwe; Endo, Satoshi

    2013-02-05

    Polyparameter linear free energy relationships (pp-LFERs) can predict partition coefficients for a multitude of environmental and biological phases with high accuracy. In this work, the pp-LFER substance descriptors of 40 established and alternative flame retardants (e.g., polybrominated diphenyl ethers, hexabromocyclododecane, bromobenzenes, trialkyl phosphates) were determined experimentally. In total, 251 data for gas-chromatographic (GC) retention times and liquid/liquid partition coefficients (K) were measured and used to calibrate the pp-LFER substance descriptors. Substance descriptors were validated through a comparison between predicted and experimental log K for the systems octanol/water (K(ow)), water/air (K(wa)), organic carbon/water (K(oc)) and liposome/water (K(lipw)), revealing a high reliability of pp-LFER predictions based on our descriptors. For instance, the difference between predicted and experimental log K(ow) was <0.3 log units for 17 out of 21 compounds for which experimental values were available. Moreover, we found an indication that the H-bond acceptor value (B) depends on the solvent for some compounds. Thus, for predicting environmentally relevant partition coefficients it is important to determine B values using measurements in aqueous systems. The pp-LFER descriptors calibrated in this study can be used to predict partition coefficients for which experimental data are unavailable, and the predicted values can serve as references for further experimental measurements.

  16. Organophosphate ester flame retardants in Nepalese soil: Spatial distribution, source apportionment and air-soil exchange assessment.

    Science.gov (United States)

    Yadav, Ishwar Chandra; Devi, Ningombam Linthoingambi; Li, Jun; Zhang, Gan

    2018-01-01

    Despite soil being the major terrestrial environmental reservoir and one of the significant sinks for many hydrophobic organic compounds including organophosphate ester flame retardants (OPFRs), limited information is available about concentration and fate of OPFRs contamination in urban soil in general and especially in case of Nepal. This study investigates the environmental concentration, spatial distribution and source apportionment of eight OPFRs in surface soil (n = 28) from four major cities of Nepal with special interest on air-soil exchange. Overall, significantly high concentrations of ∑ 8 OPFR were measured in soil ranging from 25-27,900 ng/g dw (median 248 ng/g dw). In terms of compositional pattern, tris(methyl phenyl) phosphate (TMPP) was the most abundant phosphorus chemical in soil, followed by tris(2-chloroisopropyl) phosphate (TCIPP), and accounted for 35-49% and 8-25% of ∑ 8 OPFRs, respectively. The high level of these OPFRs was attributed to local sources as opposed to transboundary influence from remote areas. A Spearman's rank correlation analysis exhibited weak correlation of ∑ 8 OPFRs with TOC (Rho = 0.117, p fugacity fraction (ff) results indicated a strong influence of soil contamination on atmospheric level of OPFRs via volatilization. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Removal of pharmaceuticals, polybrominated flame retardants and UV-filters from sludge by the fungus Trametes versicolor in bioslurry reactor.

    Science.gov (United States)

    Rodríguez-Rodríguez, Carlos E; Barón, Enrique; Gago-Ferrero, Pablo; Jelić, Aleksandra; Llorca, Marta; Farré, Marinella; Díaz-Cruz, M Silvia; Eljarrat, Ethel; Petrović, Mira; Caminal, Glòria; Barceló, Damià; Vicent, Teresa

    2012-09-30

    Conventional wastewater treatments are inefficient in the removal of many organic pollutants. The presence of these contaminants in the final sludge represents a source of environmental pollution due to the increasing use of biosolids in land application. A biotechnological approach which employed the fungus Trametes versicolor in a sludge-bioslurry reactor was assessed in order to remove several groups of emerging pollutants. Biological fungal activity was monitored by means of ergosterol and laccase determinations. Fifteen out of 24 detected pharmaceuticals were removed at efficiencies over 50% after the treatment, including eight completely degraded. Removal ranged between 16-53% and 22-100% for the brominated flame retardants and the UV-filters, respectively. Only two of all the detected compounds remained unchanged after the treatment. Although elimination results are promising, the toxicity of the final sludge increased after the treatment. This finding is contrary to the toxicity results obtained in similar treatments of sludge with T. versicolor in solid-phase. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Halogen-free organophosphorus flame retardants caused oxidative stress and multixenobiotic resistance in Asian freshwater clams (Corbicula fluminea).

    Science.gov (United States)

    Yan, Saihong; Wu, Huimin; Qin, Jianhui; Zha, Jinmiao; Wang, Zijian

    2017-06-01

    Halogen-free organophosphorus flame retardants are widespread in aquatic environments. Although it has been documented that they affect the behavior and reproduction of aquatic species, researches investigating cellular detoxification and the defense system in bivalves are scarce. In this study, adult Asian clams (C. fluminea) were exposed to tris (2-butoxyethyl) phosphate (TBEP) and tributyl phosphate (TBP) at 20, 200, and 2000 μg/L for 28 d. The results showed no noticeable difference in siphoning behavior. However, the siphoning behavior displayed a trend toward a slight decrease in the treatment groups. GR activity was markedly reduced compared with the control groups, whereas the levels of cyp4 significantly increased following the 2000 μg/L TBP treatments (p fluminea mainly relies on the antioxidant system to reduce damage without an increase in MDA levels following exposure to a low concentration. Moreover, mRNA expression levels of heat shock proteins (hsp 22, 40, 60, 70, and 90) were significantly down-regulated with TBEP and TBP treatments lower than 200 μg/L (p fluminea, which kept its shell closed at high concentrations to prevent xenobiotic entry. Our results provide a new insight into the different mechanisms of cellular detoxification and the MXR system of C. fluminea in response to low and high concentrations of TBEP and TBP. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Trace determination of the flame retardant tetrabromobisphenol A in the atmosphere by gas chromatography-mass spectrometry

    International Nuclear Information System (INIS)

    Xie Zhiyong; Ebinghaus, Ralf; Lohmann, Rainer; Heemken, Olaf; Caba, Armando; Puettmann, Wilhelm

    2007-01-01

    A simple and effective method has been developed for analysis of the flame retardant tetrabromobisphenol A (TBBPA) in environmental samples by using modified soxhlet extraction in combination with silica gel clean-up, derivatization with silylation reagent and gas chromatography-mass spectrometry (GC-MS) in selected ion monitoring mode (SIM). Satisfactory recoveries were achieved for the large volume sampling, soxhlet extraction and silica gel clean-up. The overall recovery is 79 ± 1%. The derivatization procedure is simple and fast, and produces stable TBBPA derivative. GC-MS with electronic impact (EI) ionization mode shows better detection power than using negative chemical ionization (NCI) mode. EI gives a method detection limit of 0.04 pg m -3 and enables to determine trace TBBPA in ambient air in remote area. The method was successfully applied to the determination of TBBPA in atmospheric samples collected over land and coastal regions. The concentrations of TBBPA ranged from below the method detection limit (0.04 pg m -3 ) to 0.85 pg m -3 . A declining trend with increasing latitude was present from the Wadden Sea to the Arctic. The atmospheric occurrence of TBBPA in the Arctic is significant and might imply that TBBPA has long-range transport potential

  20. Aquatic bioaccumulation and trophic transfer of tetrabromobisphenol-A flame retardant introduced from a typical e-waste recycling site.

    Science.gov (United States)

    Tao, Lin; Wu, Jiang-Ping; Zhi, Hui; Zhang, Ying; Ren, Zi-He; Luo, Xiao-Jun; Mai, Bi-Xian

    2016-07-01

    While the flame retardant chemical, tetrabromobisphenol-A (TBBP-A), has been frequently detected in the environment, knowledge regarding its species-specific bioaccumulation and trophic transfer is limited, especially in the highly contaminated sites. In this study, the components of an aquatic food web, including two invertebrates, two prey fish, and one predator fish, collected from a natural pond at an electronic waste (e-waste) recycling site in South China were analyzed for TBBP-A, using liquid chromatography-tandem mass spectrometry. The aquatic species had TBBP-A concentrations ranging from 350 to 1970 pg/g wet weight, with higher concentrations in the invertebrates relative to the fish species. Field-determined bioaccumulation factors of TBBP-A in the two aquatic invertebrates were nearly or greater than 5000, suggesting that TBBP-A is highly bioaccumulative in the two species. The lipid-normalized concentrations of TBBP-A in the aquatic species were negatively correlated with the trophic levels determined from stable nitrogen isotope (δ(15)N) (r = -0.82, p = 0.09), indicating that this compound experienced trophic dilution in the current food web.

  1. Bioconcentration, metabolism and neurotoxicity of the organophorous flame retardant 1,3-dichloro 2-propyl phosphate (TDCPP) to zebrafish.

    Science.gov (United States)

    Wang, Qiangwei; Lam, James Chung-Wah; Man, Yin-Chung; Lai, Nelson Lok-Shun; Kwok, Karen Ying; Guo, Yong yong; Lam, Paul Kwan-Sing; Zhou, Bingsheng

    2015-01-01

    Organophosphate flame retardants are ubiquitous environmental contaminants; however, knowledge is limited regarding their environmental health risks and toxicity. Here, we investigated the effects of acute and long-term exposure to tris(1,3-dichloro-2-propyl) phosphate (TDCPP) to the nervous system of zebrafish. Zebrafish embryos (2 h post-fertilization) were exposed to TDCPP (0-100 μg/L) for 6 months up until sexual maturation. Concentrations of TDCPP and its metabolic product (bis(1,3-dichloro-2-propyl) phosphate, BDCPP) were measured in the tissues of 5 day post-fertilization (dpf) larvae. There was no effect on locomotion, acetylcholinesterase activity, levels of the neurotransmitters dopamine and serotonin, and expression of mRNAs and proteins related to central nervous system development (e.g., myelin basic protein, α1-tubulin) in any exposure group. However, in adult fish, reductions of dopamine and serotonin levels were detected in the brains of females but not males. Downregulation of nervous system development genes was observed in both the male and female brain tissues. TDCPP concentrations were measured in adult fish tissues including the brain, and greater levels were detected in females. Our results showed that females are more sensitive to TDCPP stress than males in terms of TDCPP-induced neurotoxicity. We demonstrate that long-term exposure to lower concentrations of TDCPP in fish can lead to neurotoxicity. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Organophosphorus flame retardants and plasticizers in the aquatic environment: A case study of the Elbe River, Germany.

    Science.gov (United States)

    Wolschke, Hendrik; Sühring, Roxana; Xie, Zhiyong; Ebinghaus, Ralf

    2015-11-01

    This study reports the occurrence and distribution of organophosphorus flame retardants and plasticizers (OPEs) in the Elbe and Rhine rivers. A special focus of this investigation concerns the potential impacts of a major flood event in 2013 on the OPE patterns and levels in the Elbe River. In this river, 6 of 13 OPEs were detected, with tris-ethyl-phosphate (TEP, 168 ± 44 ng/L), tris-1,3-dichloro-2-propyl-phosphate (TDCPP, 155 ± 14 ng/L) and tris-1-chloro-2-propyl phosphate (TCPP, 126 ± 14 ng/L) identified as the dominant compounds. Relative to previous studies, an increase in the concentrations and relative contributions of TDCPP to the total level of OPEs was observed, which was likely caused by its increased use as a replacement for the technical pentaBDE formulation. During the flood event, the concentrations of OPEs were similar to the normal situation, but the mass fluxes increased by a factor of approximately ten (∼16 kg/d normal versus ∼160 kg/d flood peak). No input hotspots were identified along the transects of the Elbe and Rhine rivers, and the mass flux of OPEs appeared to be driven by water discharge. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Effects of prenatal exposure to hydoxylated PCB metabolites and some brominated flame retardants on the development of rats

    Energy Technology Data Exchange (ETDEWEB)

    Buitenhuis, C.; Cenijn, P.C.; Velzen, M. van; Gutleb, A.C.; Legler, J. [Institute for Environmental Studies (IVM), Amsterdam (Netherlands); Lilienthal, H. [Heinrich Univ., Duesseldorf (Germany). Dept. Neurobehavioural Toxicology, Medical Institute of Environmental Hygiene; Malmberg, T.; Bergman, Aa. [Stockholm Univ. (Sweden). Dept. of Environmental Chemistry; Brouwer, A.

    2004-09-15

    Possible human health effects from low-level exposure to environmental chemicals are an issue that has attracted much attention. Environmental compounds that may play a role are those that may disrupt endocrine function. Organohalogen compounds, and in particular their hydroxylated metabolites, show a striking resemblance to steroid hormones.The main objective of this research is to investigate comparative pathways of early life-stage exposure and long-term effects for several classes of organohalogens, including polychlorinated biphenyls (PCBs) and flame retardants, polybrominated bisphenols and -diphenylethers, and their hydroxylated metabolites. Due to their prevalence in human plasma, the hydroxylated PCB metabolites 4-OH-CB107 and 4-OH-CB187, as well as 6-OH-BDE47 and 2,4,6- tribromophenol, were selected as test compounds. BDE 47 has been included as a test compound due to its relatively high levels in the environment and biota, whereas tetrabromobisphenol A (TBBPA) was selected because of its high volume production. The in vivo studies involved prenatal exposure of rats to test compounds during critical stages of gonadal development and were focussed on low dose effects. Several endpoints were investigated, including endocrine (thyroid and sex steroid hormones) effects, developmental landmarks, sexual and neurobehavioural development. Blood plasma and tissue levels of test compounds were analysed to determine transplacental transfer of (hydroxylated) organohalogens.

  4. Three decades (1983-2010) of contaminant trends in East Greenland polar bears (Ursus maritimus). Part 2: brominated flame retardants.

    Science.gov (United States)

    Dietz, Rune; Rigét, Frank F; Sonne, Christian; Born, Erik W; Bechshøft, Thea; McKinney, Melissa A; Drimmie, Robert J; Muir, Derek C G; Letcher, Robert J

    2013-09-01

    Brominated flame retardants were determined in adipose tissues from 294 polar bears (Ursus maritimus) sampled in East Greenland in 23 of the 28years between 1983 and 2010. Significant linear increases were found for sum polybrominated diphenyl ether (ΣPBDE), BDE100, BDE153, and hexabromocyclododecane (HBCD). Average increases of 5.0% per year (range: 2.9-7.6%/year) were found for the subadult polar bears. BDE47 and BDE99 concentrations did not show a significant linear trend over time, but rather a significant non-linear trend peaking between 2000 and 2004. The average ΣPBDE concentrations increased 2.3 fold from 25.0ng/g lw (95% C.I.: 15.3-34.7ng/g lw) in 1983-1986 to 58.5ng/g lw (95% C.I.: 43.6-73.4ng/g lw) in 2006-2010. Similar but fewer statistically significant trends were found for adult females and adult males likely due to smaller sample size and years. Analyses of δ(15)N and δ(13)C stable isotopes in hair revealed no clear linear temporal trends in trophic level or carbon source, respectively, and non-linear trends differed among sex and age groups. These increasing concentrations of organobromine contaminants contribute to complex organohalogen mixture, already causing health effects to the East Greenland polar bears. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Characterization of organochlorine pesticides, brominated flame retardants and dioxin-like compounds in shellfish and eel from Fiji.

    Science.gov (United States)

    Lal, Vincent; Bridgen, Phil; Votadroka, Waisea; Raju, Rupantri; Aalbersberg, William

    2014-09-01

    This article gives an overview of a range of persistent organic pollutant chemical levels in shellfish (Batissa violacea and Anadara antiquata) species and eel (Gymnothorax flavimarginatus) from Fiji. As there is limited data in published literature to date, this paper reports first data on a range of persistent organic pollutants and highlights the more prominent POP chemicals present in marine biota in Fiji. A significant number of POP chemicals were detected (e.g. 17 PCDD/PCDF, 12dl-PCBs, organochlorine pesticides and brominated flame retardants), the concentrations found were generally low (e.g. parts per billion level). The low levels of contamination are indicative of a low input from long range and short-range transport as well as few local point sources. Also concentrations of POPs in eel and shellfish from Fiji are low in comparison to wild species in other regions and are within acceptable limits for POP chemicals in fish and fishery products set by the European Union. It describes also results of early studies on basic POPs levels in shellfish in several Pacific Island Countries, which generally show relatively low levels. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Highly efficient separation of surfactant stabilized water-in-oil emulsion based on surface energy gradient and flame retardancy.

    Science.gov (United States)

    Long, Mengying; Peng, Shan; Deng, Wanshun; Miao, Xinrui; Wen, Ni; Zhou, Qiannan; Deng, Wenli

    2018-06-15

    Surface energy gradient would generate an imbalance force to drive tiny water droplets in dry air from the hydrophilic bumps to superhydrophobic domains, which has found on the Stenocara beetle's back. Inspired by this phenomenon, we introduced a pristine superhydrophilic filter paper on the lower surface energy superhydrophobic filter paper. ZnSn(OH) 6 particles and polydimethylsiloxane were mixed to prepare the superhydrophobic coating, and the coating was spray-coated on the poly(dialkyldimethylammonium chloride) covered filter paper to separate the span 80 stabilized water-in-isooctane emulsion. A pristine filter paper was added on the superhydrophobic filter paper to fabricate another membrane for separation. The results revealed that with a pristine filter paper, the membrane performed higher efficiency and more recyclability, and it could separate the emulsions with higher surfactant concentrations. The stabilized water droplets passed the superamphiphilic surface, and hindered by the superhydrophobic surface, generating a surface energy gradient for better separation. In addition, the superhydrophobic membrane could be protected from fire to some degree due to the introduced ZnSn(OH) 6 particles with excellent flame retardancy. This easy and efficient approach via simply bringing in pristine superhydrophilic membrane has great potential applications for water-in-oil emulsion separation or oil purification. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. Occurrence of emerging flame retardants from e-waste recycling activities in the northern part of Vietnam

    Directory of Open Access Journals (Sweden)

    Masayuki Someya

    2016-06-01

    Full Text Available This study investigated the contamination status of 21 emerging flame retardants (FRs in soils (n = 32 and river sediments (n = 8 from an e-waste recycling (EWR site in the northern part of Vietnam. Among analyzed FRs, higher levels of decabromodiphenyl ethane (DBDPE (ND–4200 ng/g dw, 1,2-bis-(2,4,6-tribromophenoxyethane (BTBPE (ND–350 ng/g dw and Dechlorane Plus isomers (DPs (ND–65 ng/g dw were found in soils near EWR workshops and open burning places. The highest concentrations of DBDPE (20 ng/g dw, BTBPE (5.7 ng/g dw and DPs (6.7 ng/g dw were also detected in sediments collected from the middle of the EWR site. The levels decreased concomitantly with increasing distance from the EWR site. These results indicate that these FRs were released to the surrounding environment from improper recycling activities, such as manual dismantling of devices and open burning of e-wastes. Moreover, the estimated daily intakes of those FRs via soil ingestion were approximately ten times higher for children than adults. To our knowledge, this is a first comprehensive study on characterization of soil and sediment contamination by a series of emerging FRs at an EWR site in Vietnam.

  8. Brominated flame retardants in the urban atmosphere of Northeast China: concentrations, temperature dependence and gas-particle partitioning.

    Science.gov (United States)

    Qi, Hong; Li, Wen-Long; Liu, Li-Yan; Song, Wei-Wei; Ma, Wan-Li; Li, Yi-Fan

    2014-09-01

    57 pairs of air samples (gas and particle phases) were collected using a high volume air sampler in a typical city of Northeast China. Brominated flame retardants (BFRs) including 13 polybrominated diphenyl ethers (PBDEs, including BDEs 17, 28, 47, 49, 66, 85, 99, 100, 138, 153, 154, 183, and 209) and 9 alternative BFRs (p-TBX, PBBZ, PBT, PBEB, DPTE, HBBZ, γ-HBCD, BTBPE, and DBDPE) were analyzed. The annual average total concentrations of the 13 PBDEs and the 9 alternative BFRs were 69 pg/m(3) and 180 pg/m(3), respectively. BDE 209 and γ-HBCD were the dominant congeners, according to the one-year study. The partial pressure of BFRs in the gas phase was significantly correlated with the ambient temperature, except for BDE 85, γ-HBCD and DBDPE, indicating the important influence of ambient temperature on the behavior of BFRs in the atmosphere. It was found that the gas-particle partitioning coefficients (logKp) for most low molecular weight BFRs were highly temperature dependent as well. Gas-particle partitioning coefficients (logKp) also correlated with the sub-cooled liquid vapor pressure (logPL(o)). Our results indicated that absorption into organic matter is the main control mechanism for the gas-particle partitioning of atmospheric PBDEs. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Design of Safer Flame Retardant Textiles through Inclusion Complex Formation with Cyclodextrins: A Combined Experimental and Modeling Study

    Science.gov (United States)

    Zhang, Nanshan

    Triphenyl phosphate (TPP) is widely used as a phosphorus flame retardant. It is also one component of a commercial flame retardant mixture known as Firemaster 550. TPP is likely to be released into the environment due to its high volatility and has been detected at a concentration as high as 47,000 ng/m3 in air. Recent studies have also indicated that FRs like TPP could contribute to obesity and osteoporosis in humans. Cyclodextrins (CDs) are enzymatic degradation products of starch and consist of several (alpha-1,4)-linked alpha-Dglucopyranose units. CDs own a hydrophilic outside and a hydrophobic inner cavity, which enables the formation of non-covalently bonded cyclodextrin inclusion complexes (CD-ICs) with a vast array of molecules. We hypothesize that the formation of inclusion complexes between TPP and cyclodextrins will reduce its exposure yet also retain flame retarding properties of TPP, since the formation of FR-CD-ICs is expected to eliminate unnecessary loss of FRs, especially volatile FR compounds like TPP, and release them only during a fire when they are actually needed. After creating the TPP-beta-CD-IC, we applied it to polyethylene terephthalate (PET) films by a hot press technique. Flame tests indicated TPP-beta-CD-IC exhibited flame resistant performance matching that of neat TPP, even though much less TPP was contained in its beta-CD-IC. Incorporation of FRs and other chemical additives into textile substrates in the form of their crystalline CD-ICs is a promising way to reduce the exposure of hazardous chemicals to humans and to our environment while not impacting their efficacy. Two other parent CDs (alpha-CD and gamma-CD) were applied and their abilities to form ICs with guest TPP were studied. Results from a series of characterization methods, including FTIR, DSC, TGA, XRD and NMR indicated the successful synthesis of TPP-gamma-CD-IC via two routes. However, alpha-CD appears unable to form an IC with TPP, which is likely attributable to a

  10. Hypophosphite/Graphitic Carbon Nitride Hybrids: Preparation and Flame-Retardant Application in Thermoplastic Polyurethane.

    Science.gov (United States)

    Shi, Yongqian; Fu, Libi; Chen, Xilei; Guo, Jin; Yang, Fuqiang; Wang, Jingui; Zheng, Yuying; Hu, Yuan

    2017-09-05

    A series of aluminum hypophosphite (AHPi)/graphite-like carbon nitride (g-C₃N₄) (designated as CAHPi) hybrids were prepared, followed by incorporation into thermoplastic polyurethane (TPU). The introduction of CAHPi hybrids into TPU led to a marked reduction in the peak of the heat release rate (pHRR), total heat release, weight loss rate, smoke production rate and total smoke production (TSP). For instance, pHRR and TSP decreased by 40% and 50% for TPU/CAHPi20. Furthermore, the increasing fire growth index and decreasing fire performance index were obtained for TPU/CAHPi systems, suggesting reduced fire hazards. It was found that improved fire safety of TPU nanocomposites was contributed by condensed phase and gas phase mechanisms. On one hand, g-C₃N₄ accelerated the thermal decomposition of AHPi for the formation of more char layers. On the other hand, g-C₃N₄ induced AHPi to generate more free radical capture agents when exposed to flame, besides protecting AHPi against thermal oxidation.

  11. Emissions of brominated flame retardants in Asia: consideration of its potential risk form the view point of the Norwegian regulation

    Science.gov (United States)

    Kikuchi, Ryunosuke; Gerardo, Romeu; Gorbacheva, Tamara

    2010-05-01

    Flame retardants can be divided into two broad categories: additive or reactive, which can be further more divided into brominated or non-brominated sub-categories. These retardants are found in many commercial products such as computers, television sets, furniture, carpets, etc. They are of environmental concern due to their persistence, potential for bioaccumulation and widespread distribution via atmospheric transport, and possible adverse effects in wildlife and humans. Tetrabromobisphenol-A (TBBPA) is mainly used in electrical and electronic appliances (circuit board in particular), and the application of TBBPA accounts for about two thirds of the global production of brominated flame retardant (BFR). The European Union Risk Assessment does not support the restriction of TBBPA: i.e. no risk is identified for the reactive use of TBBPA such as in epoxy resin used in circuit boards. By contrast, in 2007 Norway notified the World Trade Organization of its intention to prohibit 18 substances from consumer goods (Notification No. 2007/9016/N), called the Prohibition on Certain Hazardous Substances in Consumer Products (PoHS). TBBPA is listed in this prohibition list. Marine conservation is recognized as a key issue in Norwegian fishery management e.g. wastewater management in the framework of the North Sea Declarations. TBBPA is very water-soluble, and dimethyl-TBBPA is lipophilic and may accumulate in fat. TBBPA is not readily biodegradable and can have long-term effects in the aquatic environment. Norwegian examples are summarized: TBBPA was found in marine sediment samples from Tromsø harbor (northern Norway) and in Atlantic cod from Lofoten and Varanger; TBBPA has been detected in Norwegian peregrine falcon and golden eagle eggs; and TBBPA has been detected in the blood in the general population of Norway. From these viewpoints, it can be considered that Norway needs to strictly control TBBPA emissions. In recent times, Asia has emerged as one of the leading

  12. Synthesis of mesoporous silica@Co-Al layered double hydroxide spheres: layer-by-layer method and their effects on the flame retardancy of epoxy resins.

    Science.gov (United States)

    Jiang, Shu-Dong; Bai, Zhi-Man; Tang, Gang; Song, Lei; Stec, Anna A; Hull, T Richard; Hu, Yuan; Hu, Wei-Zhao

    2014-08-27

    Hierarchical mesoporous silica@Co-Al layered double hydroxide (m-SiO2@Co-Al LDH) spheres were prepared through a layer-by-layer assembly process, in order to integrate their excellent physical and chemical functionalities. TEM results depicted that, due to the electrostatic potential difference between m-SiO2 and Co-Al LDH, the synthetic m-SiO2@Co-Al LDH hybrids exhibited that m-SiO2 spheres were packaged by the Co-Al LDH nanosheets.