Brominated flame retardants polybrominated

Ikonomou, M.G. Rayne, S. Addison, R.F. 2002a, Exponential increases of the brominated flame retardants, polybrominated diphenyl ethers, in the Canadian Arctic from 1981 to 2000. Environ. Sci. Technol. 36 1886—1892. 

Eriksson P, Jakobsson E, Fredriksson A. 1998. Developmental neurotoxicity of brominated flame-retardants, polybrominated diphenyl ethers, and tetrabromo-bis-phenol A. Organohalogen Compounds 35 375-377. 

Gustafsson K, Bjork M. Burreau S, et al. 1999. Bioaccumulation kinetic of brominated flame retardants (polybrominated diphenyl ethers) in blue mussels Mytilus edulis). Environ Toxicol Chem 18(6) 1218-1224. 

One of the main concerns with plastic resin pellets is that they carry persistent organic pollutants (POPs). POPs are human-made chemicals used in a variety of anthropogenic activities, including industry, agriculture and daily life. POPs include polychlorinated biphenyls (PCBs), different sorts of organochloiine pesticides (e.g. DDTs and HCHs) and brominated flame retardants (polybrominated diphenyl ethers, or PBDEs). Because of their very slow rate of degradation, POPs are persistent in the environment. POPs are... 

Incineration of a collection of polymers with 10 different kinds of brominated flame retardants has been studied under standardized laboratory conditions using varying parameters including temperature and air flow. Polybrominated diphenyl ethers like the deca-, octa-, and pentabromo compounds yield a mixture of brominated dibenzofurans while burning in polymeric matrices. Besides cyclization, debromination/hydrogenation is observed. Influence of matrix effects and burning conditions on product pattern has been studied the relevant mechanisms have been proposed and the toxicological relevance is discussed. 

M. Freiberg, D.L. McAllister, C.J. Mazac, P. Ranken Analysis of Trace Levels of Polybrominated Dibenzo-p-dioxins and Dibenzofurans in Brominated Flame Retardants Presented on June 30, 1993 at Orgabrom 93 in Jerusalem. 

In addition, the concern about e-waste not only focuses on its vast quantity generated daily, but also more on the need to handle the toxic chemicals embedded in it. It is well known that e-waste contains lead, beryllium, mercury, cadmium (Cd), and brominated flame retardants (BFRs) among other chemical materials [3]. Furthermore, highly toxic chemicals such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polybrominated dibenzo-p-dioxins and dibenzo-furans (PBDD/Fs) can be formed during the recycling process [4]. 

Shi T, Chen SJ, Luo XJ, Zhang XL, Tang CM, Luo Y, Ma YJ, Wu JP, Peng XZ, Mai BX (2009) Occurrence of brominated flame retardants other than polybrominated diphenyl ethers in environmental and biota samples from southern China Chemosphere 74(7) 910-916. doi 10.1016/j. chemosphere.2008.10.047... 

Keywords Bioaccumulation, Bioavailability, Brominated flame retardants, Hexabromocyclododecane, Polybrominated diphenyl ether... 

The replacement of established chemistries with newer ones is one of the classic drivers of change in the chemical industry. One of the current hotbeds of this kind of change is the replacement of brominated flame retardants in polymer formulations. The brominated flame retardants under the most scrutiny have been polybrominated diphenyl ethers, particularly penta- and octabromodiphenyl ether, which have been shown to be persistent in the environment and to bioaccumulate. Great Lakes Chemical is voluntarily phasing out penta- and octa-BDEs by the end of next year. The phaseout is made possible by the clean bill of health granted by EPA for Firemaster 550, a replacement for penta-BDE in flexible PU applications. BRG Townsend claims the phaseout of penta-BDE and octa-BDE is not as earth shattering as would be an exit from deca-BDE, a styrenics additive that is produced in the highest volume of the PBDEs. 

Proposals to ban two types of brominated flame retardants in electrical and electronic goods are raising controversy in Bmssels. The EU DG XI (Environment) is circulating a draft proposed directive on waste electrical and electronic equipment under which polybrominated biphenyls and polybrominated diphenyl ethers would be banned by 1 January 2004. The proposal is circulating despite risk assessments which show that there is no particular cause for concern and no need for further risk assessment. 

Due to their adverse health effects, several restrictions and bans have been imposed on the usage of polybrominated diphenyl ethers (PBDEs), namely the penta-, octa-, and deca-BDE formulations, in Europe, China, North America, and Japan (http //www. bsef.com). The restricted usage of these PBDEs increased the market demand for substitute brominated flame retardants (BERs) including hexabromocyclododecanes... 

Sjodin A, Bergman A, Pattersson DG Jr (2009) A review on human exposure to brominated flame retardants - particularly polybrominated diphenyl ethers. Environ Int 29 829-839... 

The term brominated flame retardant (BFR) incorporates more than 175 different types of substances, which form the largest class of flame retardants other classes are phosphorus-containing, nitrogen-containing, and inorganic flame retardants (Bimbaum and Sttaskal 2004). The major BFR substances in use today (depicted in Fig. 4.6) are tetrabromobisphenol A (TBBPA), hexabromocyclododecane (HBCD), and mixtures of polybrominated diphenyl ethers (PBDEs) (namely, deca-bromodiphenyl ether (DBDE), octabromodiphenyl ether (OBDE), and pentabro-modiphenyl ether (pentaBDE)). 

The POCs include, but are certainly not limited to the polychlorinated biphenyls (PCBs) and the organochlorine pesticides, including those in current use, restricted use and historic use brominated flame retardants including polybrominated diphenyl ethers PAHs and the sometimes more toxic transformation products of these chemicals. Table 1 summarizes information on some of the POCs more commonly detected in alpine environments. 

Luijk R, Covers HAJ. 1992. The formation of polybrominated dibenzo-p-dioxins (PBDDs) and dibenzofurans (PBDFs) during pyrolysis of polymer blends containing brominated flame retardants. Chemosphere 25(3) 361-374. 

With the demise of PBBs as a viable product, the brominated flame retardant industry turned to polybrominated diphenyl ethers (PBDEs) as a replacement. PBDEs have become a popular product for example, furniture-grade polyurethane foam is now treated with 1-10% by weight of PBDEs to make this material safe for home use [27]. Not surprisingly, the use of PBDEs has increased over the years, and global annual sales are now 70 000 metric tons [27]. 

PBDEs Considered the new PCBs, polybrominated diphenyl ethers are a group of brominated flame retardants used in lots of products, including the foam in couches and mattresses, and plastic TV and computer monitors (Dell and HP, among others, have banned them). One of the reasons PBDEs are so hard to avoid is that they re not bound to the molecules in materials, so toxic residue can escape in the form of dust. Most kinds of PBDEs have been banned in Europe since 2004, and American women carry ten to seventy times as many PBDEs in their breast milk, tissues, and blood as Europeans do. Exposure to PBDEs during fetal development can negatively affect how the brain functions. 

The main types of brominated flame retardants (BFRs) are polybromin-ated biphenyls (PBBs), PBDEs, and tetrabromobisphenol A (TBBPA). PBDEs have replaced PBBs, which are the first brominated organic compounds to be used as flame retardants and were phased out because of environmental issues, but are now being replaced by TBBPA (Renner, 2000). The global consumption of BFRs is estimated to be 203425 tons in 1999 with PBDEs accounting for 33% (Fig. 2.10). Deca-BDEs, 82% of total PBDEs, are the most widely used product. Domestic BFR consumption in South Korea in 2002 was 49050 tons, of which 25% (i.e., 12408 tons) was PBDEs with deca-BDE accounting for 12324 tons and penta- and octa-BDEs accounting for 84 tons (KMOE, 2005c). Imported amounts of each product in 2003 showed a similar distribution to the consumption estimated in 2002 (Fig. 2.10). In BFR market of Western Europe, consumption of PBDEs has declined from 26% in 1996 to 11% in 1998 (DEPA, 1999). Penta-BDEs product has been restricted for over one decade and is now banned within Europe. Furthermore, there has... 

The U.S. EPA issued the Polybrominated Diphenyl Ethers (PBDEs) Project Plan report in May 2006.90 It identified a number of activities that the EPA was conducting regarding PBDEs, as well as activities it intended to initiate or consider. In March 2008, the second progress report, Tracking Progress on U.S. EPA s Polybrominated Diphenyl Ethers (PBDEs) Project Plan Status Report on Key Activities, was issued.91 Updates were reported to the assessment of substitutes for penta-BDE and octa-BDE, assessment and evaluation of deca-BDE, assessment of the risks of penta-BDE and octa-BDE, and tracking of developments concerning other brominated flame-retardants of interest. 

Wanner, A., Reichl, L., Kohler, J., Schadel, S., Rupprich, A., Kdmer, W. (2007) Polybrominated diphenyl ether (PBDE) in Italian ryegrass exposed near to Bavarian shredder plants. In Proceedings of the 4th International Workshop on Brominated Flame Retardants, Amsterdam, The Netherlands, 24-27 April 2007 (unpaginated). 

Other brominated compounds of environmental concern are also chiral. Polybrominated biphenyls, like PCBs, were used as capacitor fluids in mixtures of congeners (e.g. Fire-master), and are also atropisomeric [4]. While HBCDD is the most common chiral brominated flame retardant, others exist, such as 2,3-dibromopropyl-2,4,6-tribromophenyl ether (Figure 4.7). As of this writing, little is known about environmental occurrence, fate, and effects of these other chiral flame retardants, and with one exception [5] nothing has yet been published on their enantiomers. 

However, especially brominated flame retardants are creating problems when electronic and electrical equipment reach end of life. If landfilled, toxic brominated flame retardants may slowly leach ont into the groundwater, where they persist for several years or they can evolve into the air. If waste materials are burned toxic polybrominated dioxins and furans can be formed [53, 50]. 

---