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Concept: Brominated flame retardant

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BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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 expected. Most flame retardants, including TDCPP, were detected in 100% of dust samples collected from the airplanes. The concentrations of BDE 209 were elevated by orders of magnitude relative to residential and office environments.

Concepts: Fire retardant, Flame retardant, Decabromodiphenyl ether, Bromine, Brominated flame retardant, Flame retardants, Hexabromocyclododecane, Aircraft

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Children are exposed to flame retardants from the built environment. Brominated diphenyl ethers (BDE) and organophosphate-based flame retardants (OPFRs) are associated with poorer neurocognitive functioning in children. Less is known, however, about the association between these classes of compounds and children’s emotional and social behaviors. The objective of this study was to determine if flame retardant exposure was associated with measurable differences in social behaviors among children ages 3-5 years.

Concepts: Fire retardant, Flame retardant, Decabromodiphenyl ether, Polychlorinated biphenyl, Brominated flame retardant, Flame retardants, Antimony trioxide

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About 200 second-hand plastic toys sourced in the UK have been analysed by x-ray fluorescence spectrometry for hazardous elements (As, Ba, Cd, Cr, Hg, Pb, Sb, Se) and Br as a proxy for brominated flame retardants. Each element was detected in > 20 toys or components thereof with the exception of As, Hg and Se, with the frequent occurrence of Br, Cd and Pb and at maximum concentrations of about 16,000, 20,000 and 5000 μg g-1, respectively, of greatest concern from a potential exposure perspective. Migration was evaluated on components of 26 toys under simulated stomach conditions (0.07 M HCl) with subsequent analysis by inductively coupled plasma spectrometry. In eight cases, Cd or Pb exceeded their migration limits as stipulated by the current EU Toy Safety Directive (17 and 23 μμ g-1, respectively), with Cd released from yellow and red Lego bricks exceeding its limit by an order of magnitude. Two further cases were potentially non-compliant based on migratable Cr, with one item also containing > 250 μg g-1 migratable Br. While there is no retroactive regulation on second-hand toys, consumers should be aware that old, mouthable, plastic items may present a source of hazardous element exposure to infants.

Concepts: Spectroscopy, X-ray fluorescence, Chemistry, Flame retardant, Plasma, Brominated flame retardant, Toy, Lego

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Higher house dust levels of PBDE flame retardants (FRs) have been reported in California than other parts of the world, due to the state’s furniture flammability standard. However, changing levels of these and other FRs have not been evaluated following the 2004 U.S. phase-out of PentaBDE and OctaBDE. We analyzed dust collected in 16 California homes in 2006 and again in 2011 for 62 FRs and organohalogens, which represents the broadest investigation of FRs in homes. Fifty-five compounds were detected in at least one sample; 41 in at least 50% of samples. Concentrations of chlorinated OPFRs, including two (TCEP and TDCIPP) listed as carcinogens under California’s Proposition 65, were found up to 0.01% in dust, higher than previously reported in the U.S. In 75% of the homes, we detected TDBPP, or brominated “Tris,” which was banned in children’s sleepwear because of carcinogenicity. To our knowledge, this is the first report on TDBPP in house dust. Concentrations of Firemaster 550 components (EH-TBB, BEH-TEBP, and TPHP) were higher in 2011 than 2006, consistent with its use as a PentaBDE replacement. Results highlight the evolving nature of FR exposures and suggest that manufacturers continue to use hazardous chemicals and replace chemicals of concern with chemicals with uncharacterized toxicity.

Concepts: DNA, United States, Fire retardant, Plastic, Decabromodiphenyl ether, Brominated flame retardant, Flame retardants, Dust explosion

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Flame-retardant and self-healing superhydrophobic coatings are fabricated on cotton fabrics by a convenient solution dipping method, which involves the sequential deposition of a trilayer of branched poly(ethylenimine) (bPEI), ammonium polyphosphate (APP) and fluorinated-decyl polyhedral oligomeric silsequioxane (F-POSS). When directly exposed to flame, such a trilayer coating generates a porous char layer because of its intumescent effect, successfully endowing the coated fabric with self-extinguishing property. Meanwhile, the preserved F-POSS in cotton fabrics and APP/bPEI coating produce a superhydrohobic surface with self-healing function. The coating can repetitively and autonomically restore superhydrophobicity once the superhydrophobicity is damaged. The resultant cotton fabrics, which are flame resistant, waterproof and self-cleaning, can be readily cleaned with simple water rinsing. Thus, the integration of self-healing superhydrophobicity with flame-retardancy provides a practical way to solve the problem regarding the washing durability of the flame-retardant coatings. The flame-retardant and superhydrophobic fabrics can endure more than 1000 cycles of abrasion under a pressure of 44.8 kPa without losing its flame-retardancy and self-healing superhydrophobicity, showing potential applications as multifunctional advanced textiles.

Concepts: Cotton, Geology, Coating, Textile, Yarn, Coatings, Brominated flame retardant, Tent

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In order to confirm the possibility that recycled fractions from the Waste Electrical and Electronic Equipment (WEEE) stream were illegally entering the European market in black polymeric food-contact articles (FCAs), bromine quantification, brominated flame retardant (BFR) identification combined with WEEE relevant elemental analysis and polymer impurity analysis were performed. From the 10 selected FCAs, seven samples contained a bromine level ranging from 57 till 5975 mg kg(-1) which is lower than expected to achieve flame retardancy. The BFRs which were present were tetrabromobisphenol A (TBBPA), decabromodiphenylether (decaBDE), decabromodiphenylethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE). Typical elements used in electronic equipment and present in WEEE were detected either at trace level or at elevated concentrations. In all cases when bromine was detected at higher concentrations, concurrently antimony was also detected which confirms the synergetic use of antimony in combination with BFRs. This study describes also the measurement of rare earth elements (REEs) where combinations of cerium, dysprosium, lanthanum, neodymium, praseodymium and yttrium which were detected in four of the seven BFR positive samples. Additionally, the polymer purity was investigated where in all cases foreign polymer fractions were detected. Despite the fact that this study was carried-out on a very small amount of samples there is a significant likelihood that WEEE has been used for the production of FCAs.

Concepts: Flame retardant, Rare earth element, Chemical elements, Yttrium, Brominated flame retardant, Cerium, Lanthanide, Monazite

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Paired human breast milk and scalp hair samples (n=30) were obtained in 2008 from primipara and multipara mothers living in two locations in the Philippines viz., Payatas, a waste dumpsite, and Malate, a non-dumpsite. Samples were analyzed for three groups of organohalogenated compounds, such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs). PCBs were the predominantly identified compounds (median: 70ng/g lipid wt.) in all the breast milk samples. In the human milk, CB-153 was the most dominant PCB congener (17-44% contribution to the sum PCB), closely followed by CB-138 (12-35%), CB-118 (4-12%), CB-180 (2-13%), CB-187 (3-13%), and CB-170 (1.5-10%). Levels of PBDEs (median: 3.0ng/g lipid wt.) in human milk samples from the Philippines were similar to other Asian or European countries. BDE-47, -99, -100 and -153 were the major PBDE congeners. For HBCDs, the α-isomer was predominant followed by the γ-HBCD isomer in the both locations. PBDE levels in human milk were significantly higher in the dumpsite (3.9ng/g lipid wt.) than in the non-dump site (2.2ng/g lipid wt.). PBDE concentrations (including BDE-209) were significantly higher (median: 70ng/g hair) than those of PCBs (median: 30ng/g hair) and HBCDs (median: 1.0ng/g hair) in all the scalp hair samples. To our knowledge, this is the first report on HBCDs in human scalp hair. PBDE congeners in scalp hair were dominated by BDE-209 and BDE-47. On a congener basis, the levels of PBDEs found in scalp hair were higher than those in Spain (children and adults) and China (general people). PCB levels found in scalp hair were higher than those in Greece, Romania and Belgium, but lower than those in China. In this study, there were no significant differences in the concentration of PCBs and HBCDs in human milk; and PCBs, HBCDs and PBDEs in human scalp hair from the two different locations. No significant correlations were observed between PCBs, PBDEs and HBCDs levels and age of mothers in this study, which may be due to the small number of samples. Furthermore, there was no correlation between milk and hair levels for more persistent compounds (PCB-153, PCB-138, or BDE-47), and thus it is worthy to follow-up in future studies along with more number of samples. This is the first report to provide measurement data for PCBs, PBDEs and HBCDs in paired milk and hair of populations in the Philippines.

Concepts: Milk, Flame retardant, Breast, Breast milk, Polychlorinated biphenyl, Biphenyl, Brominated flame retardant, Flame retardants

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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 180μg/kg dry wt and ND to 1.4μg/kg dry wt, respectively, in the reference sites and from 0.20 to 430μg/kg dry wt and ND to 2.5μg/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.

Concepts: Pollution, Flame retardant, Waste management, Waste, Brominated flame retardant, Flame retardants, Hazardous waste, Hexabromocyclododecane

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The accumulation of phthalate esters, brominated flame retardants (BFRs) and organophosphate esters (OPEs) by clothing from indoor air and transfer via laundering to outdoors were investigated. Over 30 days cotton and polyester fabrics accumulated 3475 and 1950 ng/dm(2) ∑5phthalates, 65 and 78 ng/dm(2) ∑10BFRs, and 1200 and 310 ng/dm(2) ∑8OPEs, respectively. Planar surface area concentrations of OPEs and low molecular weight phthalates were significantly greater in cotton than polyester and similar for BFRs and high molecular weight phthalates. This difference was significantly and inversely correlated with KOW, suggesting greater sorption of polar compounds to polar cotton. Chemical release from cotton and polyester to laundry water was >80% of aliphatic OPEs (log KOW < 4), < 50% of OPEs with an aromatic structure, 50-100% of low molecular weight phthalates (log KOW 4-6), and < detection-35% of higher molecular weight phthalates (log KOW > 8) and BFRs (log KOW > 6). These results support the hypothesis that clothing acts an efficient conveyer of soluble semivolatile organic compounds (SVOCs) from indoors to outdoors through accumulation from air and then release during laundering. Clothes drying could as well contribute to the release of chemicals emitted by electric dryers. The results also have implications for dermal exposure.

Concepts: Molecule, Chemistry, Flame retardant, Phthalate, Polyester, Textile, Brominated flame retardant, Clothing

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A new method for rapid determination of 73 target organic environmental contaminants including 18 polychlorinated biphenyls, 16 organochlorinated pesticides, 14 brominated flame retardants and 25 polycyclic aromatic hydrocarbons in fish and fish feed using gas chromatography coupled with triple quadrupole tandem mass spectrometry (GC-MS/MS) was developed and validated. GC-MS/MS in electron ionization mode was shown to be a powerful tool for the (ultra)trace analysis of multiclass environmental contaminants in complex matrices, providing measurements with high selectivity and sensitivity. Another positive aspect characterizing the newly developed method is a substantial simplification of the sample preparation, which was achieved by an ethyl acetate QuEChERS (quick, easy, cheap, effective, rugged and safe) based extraction followed by silica minicolumn clean-up. With use of this sample preparation approach the sample laboratory throughput was increased not only because six samples may be prepared in approximately 1 h, but also because all the above-mentioned groups of contaminants can be determined in a single GC-MS/MS run. Under the optimized conditions, the recoveries of all target analytes in both matrices were within the range from 70 to 120 % and the repeatabilities were 20 % or less. The method quantification limits were in the range from 0.005 to 1 μg kg(-1) and from 0.05 to 10 μg kg(-1) for fish muscle tissue and fish feed, respectively. The developed method was successfully applied to the determination of halogenated persistent organic pollutants and polycyclic aromatic hydrocarbons in fish and fish feed samples.

Concepts: Mass spectrometry, Polycyclic aromatic hydrocarbon, Benzene, Flame retardant, Persistent organic pollutant, Polychlorinated biphenyl, Soil contamination, Brominated flame retardant