Pentabromodiphenyl ethers

Similar results are obtained from incineration of polymeric materials with octabromo- and pentabromodiphenyl ether (refs. 11,12). The temperature with the maximum PBDF-yield depends on the kind of polymeric matrix. All three bromo ethers 1-2 give the same isomer distribution pattern with preference for tetrabrominated dibenzofiirans. The overall yield of PBDF is lower for incineration of pentabromobiphenyl ether 2, 4 % at 700°C compared to 29 % for ether 1 at 500 °C (ref. 12). The preferred formation of tetrabrominated fiirans observed at all temperatures cannot be a result of thermodynamic control of the cyclisation reaction it is likely due to the special geometry of the furnaces. One explanation is that a spontaneous reaction occurs at approximately 400°C while the pyrolysis products are transferred to the cooler zones of the reactor details can be found elsewhere (ref. 12). 

The challenge was to avoid the use of hazardous brominated fire retardants such as polybrominated biphenyl (PBB) and pentabromodiphenyl ether (PBDE). The first strategy was to replace PBB and PBDE with tetrabromo-bisphenol-A (TBBA). This has a much lower toxicity, but is still a brominated fire retardant with safety concerns. An improvement... 

EPA IRIS, Integrated risk information system regarding decabromodiphenyl ether, octabromo-diphenyl ether and pentabromodiphenyl ether)... 

There is a huge variety of PBDEs considering that there might be from one to ten bromine atoms bound to the diphenyl ether molecule. Among all the PBDEs, the commercial mixtures of decabromodiphenyl ether (deca-BDE), octabromodiphenyl ether (octa-BDE) and pentabromodiphenyl ether (penta-BDE) are the products that are most found in the environment. Related to octa-BDE and penta-BDE mixtures, their commercial use was banned in the European Union in 2004 and that year their leading manufacturers in North America stopped producing them on a voluntary basis [2], Regarding the deca-BDE mixture, since July 2008, its use has been... 

This article reports on two related pieces of news firstly that Albemarle Corp. of the USA has introduced a new reactive flame retardant, Saytex RX 8500 , as a replacement for pentabromodiphenyl ether (penta-BDE) in the production of flame-retardant PU foam. Secondly that Great Lakes Chemical Corp., the only manufacturer of penta-BDE, has announced plans to voluntarily phase out and cease production of this, and also octa-BDE, at the end of 2004. 

Proposals for the EU to press for nine hazardous substances to be banned or severely restricted under two international treaties on persistent organic pollutants were issued by the European Commission in August. The substances include polychlorinated naphthalenes and the flame retardant pentabromodiphenyl ether, concentrations of which were recently found to be rising in the Arctic environment and wildlife. 

The DfE Program and its partners fully exercised the principles of informed substitution for the first time in the alternatives analysis for pentabromodiphenyl ether, as part of its Furniture Flame Retardancy Partnership [9]. The analysis brought together a diverse stakeholder group, elicited new data from flame retardant manufacturers, and created an informative summary of experimental and modeled data. The industry used the data from the report as part of their move to safer alternatives. 

Informing Real-Time Substitution Decisions Chemical Alternative Assessment for Pentabromodiphenyl Ether... 

In the early 2000s, a serious dilemma arose for industry, public health, and environmental advocates. Pentabromodiphenyl ether (pentaBDE) (Figure 5.1) had... 

Table 5.2 A portion of Table 4-1 from the pentabromodiphenyl ether alternatives assessment as an example of the presentation of the information to inform selection of alternatives3. ... 

Peltola, J. and Yla-Mononen, L. (2000) Pentabromodiphenyl Ether as a Global POP Report, http //www.pops.int/documents/ meetings/ 1/chemlisting/ pentaBDEfinal.pdf (last accessed... 

Pentabromodiphenyl ether Octabromodiphenyl ether Decabromodiphenyl ether... 

Pentabromodiphenyl ether pentabromodiphenyl oxide pentabromobiphenyl oxide benzene, 1,1-oxybis, pentabromo derivative... 

DeBDE=Decabromodiphenyl ether HpBDE=Heptabromodiphenyl ether HxBDE=Hexabromodiphenyl ether NoBDE=Nonabromodiphenyl ether OcBDE=Octabromodiphenyl ether PBDE=Polybrominated diphenyl ether PeBDE=Pentabromodiphenyl ether TeBDE=Tetrabromodiphenyl ether TrBDE=Tribromodiphenyl ether... 

Reference doses (RfDs) for decabromodiphenyl ether, octabromodiphenyl ether, and pentabromodiphenyl ether are IxlO, 3x10, and 2x10 mg/kg/day, respectively (IRIS 2002). 

Decabromodiphenyl ether Octabromodiphenyl ether Pentabromodiphenyl ether... 

Decabromobiphenyl Decabromodiphenyl ether Hexabromo-1, T-biphenyl Octabromobiphenyl Octabromodiphenyl ether p-Bromodiphenyl ether Pentabromodiphenyl ether... 

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