Poly-brominated diphenyl ethers

To explore the geographical distribution and temporal trends of poly-brominated diphenyl ethers (PBDEs) in the Great Lakes in more detail, lake trout from Lakes Superior, Michigan, Huron, and Ontario and walleye from Lake Erie, collected during the period of 1980-2000, were analyzed by Zhu and Hites [19]. The concentrations of fifteen PBDE congeners were de-... 

Table 9 shows that there are reasonably good data available for the poly-brominated diphenyl ethers (PBDEs), but there is much less information for the other BFRs. While the polybrominated biphenyls (PBBs) are no longer in production or use, it is clear that these compounds are persistent in the environment and in people thus, it would be prudent to continue to monitor the concentrations of these compounds in (at least) the sediment and fishes of the lakes. The other BFRs (HBCD, TBE, and PEB) are not currently abundant in the lakes, but the likelihood of their increased use in the future suggests that they too should be monitored in the sediment and fishes of the lakes. Of course, the... 

New Hampshire Developing public-health laboratory capacity to biomonitor for arsenic, mercury, phthalates, poly-brominated diphenyl ethers and planning pilot studies to estimate body burden of environmental toxicants using newly developed biomonitoring analytic methods (CDC 2005). 

Darnerud, P.O., Eriksen, G.S., Johannesson, T., Larsen, P.B., Viluksela, M., 2001. Poly-brominated diphenyl ethers Occurrence, dietary exposure, and toxicology. Environ. Health Perspect. 109, 49-68. 

Bocio, A., Llobet, J.M., Domingo, J.L., Corbella, J., Teixido, A., Casas, C., 2003. Poly-brominated diphenyl ethers (PBDEs) in foodstuffs Human exposure through the diet. J. Agric. Food Chem. 51, 3191-3195. 

Ter Schure, A. F. H., Larsson, R, Agrell, C., Boon, J. P. (2004) Atmospheric transport of poly-brominated diphenyl ethers and polychlorinated biphenyls to the Baltic Sea. Environ. Sci. Technol., 38 1282-1287. 

In response to the continuing discovery of the persistence, bioaccumulative properties, and toxicity of POPs, regional, national and international policies ban the intentional production of compounds, such as polychlorinated biphenyls (PCBs), several organochlo-rine pesticides, such as mirex and dieldrin, and the brominated flame retardants poly-brominated diphenyl ethers (penta-BDE and octa-BDE, and most recently, deca-BDE). Policies and programs have also targeted the unintentional production and release of POPs such as polychlorinated dibenzodioxins and furans (PCDD/Fs). Evidence of the success of these policies has been seen in immediate reductions of air concentrations, followed by declining concentrations in water bodies, soils, biota and our food supplies... 

No matter the source, flame retardants, especially the poly brominated diphenyl ethers (PBDE s), are coming under scrutiny because they are persistent organic pollutants (POPs). They are appearing in human samples, most notably serum, adipose fat tissue and breast milk. PBDE s are also under investigation as potential endocrine mimickers or endocrine disrupters. As a result, PBDE s are the most highly regulated flame retardants. Their environmental fate will continue to be a topic of research for years to come. 

Polybrominated Biphenyls (PBBs) and Poly brominated Diphenyl Ethers (PBDEs)... 

Covad, A., Voorspoels, S., and de Boer, J., Determination of brominated flame retardants, with emphasis on poly brominated diphenyl ethers in environmental and human samples. Environ. Int., 29, 735-756, 2003. 

Many workshops and conferences on the bromine compounds have been held under auspices of govemment/nongovemmental organizations and industry (examples References 158-160). Concern has lately focused on the lower brominated diphenyl ethers (such as penta-) which are detected widely in the environment. In a review, Dutch researchers conclude that the toxicity mechanism of poly-brominated diphenyl ethers is the same as that of the dioxins, and, although the present concentrations are not a large risk, these ethers are accumulative. Decabromodiphenyl oxide is less toxic than the less-brominated congeners, and its absorption from the gastrointestinal tract is low. 

Maruyama H, Homma K, Wada A, Shiokawa Y. The rapid analysis of PBDEs (poly brominated diphenyl ethers) utilizing the ion attachment mass spectrometry. Organohalogen Compd. 2007 69 2767-68. 

Ema M, Fujii S, Hirata-Koizumi M et al (2007) Two-generation reproductive toxicity study of the flame retardant hexabromocyclododecane in rats. Reprod Toxicol 25 335-351 Eriksson P, Fischer C, Fredriksson A (2006) Poly-brominated diphenyl ethers, a group of brominated flame retardants, can interact with polychlorinated biphenyls in enhancing developmental neurobehavioral defects. Toxicol Sci 94 302-309 Eskenazi B, Chevrier J, Rauch SA et al (2013) In utero and childhood polybrominated diphenyl ether (PBDE) exposures and neurodevelopment in the CHAMACOS study. Environ Health Perspect 121 257-261... 

Use of some of the flame retardants, particularly brominated ones (PBDEs, or poly-brominated diphenyl esters), was prohibited by European Union Risk Assessment program. Among them were pentabromodiphenyl ether (pentaBDE), which was used primarily in polyurethane foam, and octabromodiphenyl ether (octaBDE), used mainly in electrical and electronic equipment and automobiles (both were prohibited by EU in August, 2004). In the United States, production of pentaBDE was ceased in 2004 and its mannfacture and import into the United States is prohibited. Octa-BDE was schednled to be prohibited in 2006 in a number of states in the United States... 

The European Union has taken the lead in restricting the use of some hazardous materials in the manufacture of electrical and electronic hardware. The program, referred to as Restriction of Hazardous Substances (RoHS), applies to all electrical and electronic products produced in Europe and products imported from other countries, thus has very broad application. The regulations put into force on July 1, 2006, apply to lead, cadmium, mercury, hexavalent chromium (Cr ), poly-brominated biphenyl (PBB), and polybrominated diphenyl ether (PBDE). The RoHS guideline document specifies 0.1% or 1,000 ppm as the maximum amount permitted for lead, mercury, Cr" " , PBB, and PBDE and 0.01% or 100 ppm for cadmium. The document also describes guidelines for sample preparation and analyses of the restricted materials. 

Luyk [251] has examined formation of poly-brominated dibenzo-/ -dioxins (PBDD) and diben-zofurans (PBDF) during thermal processing of polymers containing polybrominated diphenyl ethers. The formation of PBDDs and PBDFs is a result of thermal and mechanical stress in the melt phase or condensed phase. The yield depends on temperature... 

Halogenatlon. Poly(2,6-dimethyl- and 2,6-diphenyl-l,4-phenylene ether) can be aryl-brominated simply by exposure to a bromine solution no catalyst is required.6 In fact, the use of Lewis acid catalysts to promote the chlorination of poly(2,6-dimethy1-1,4-phenylene ether) leads to substantial degradation of the molecular weight of the chlorinated products.7 Membranes produced from ring brominated PPO (40% wt Br) exhibited enhanced permeability to CHi and CO2 and proved to be more selective in separating CH4/CO2 mixtures.8... 

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