3,3 ,4,4 ,5-Pentabromodiphenyl ether PBDE

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... 

Reported octanol-air partition coefficients of 2,2, 3,4,4 -pentabromodiphenyl ether (PBDE 85) at various temperatures... 

FIGURE 10.1.5.23.1 Logarithm of Kqa versus reciprocal temperature for 2,2, 4,4, 5-pentabromodiphenyl ether (PBDE-99). 

Fowles JR, Fairbrother A, Baecher Steppan A, et al. Immunologic and endocrine effects of the flame retardant pentabromodiphenyl ether (PBDE 71) in C57BL/J mice. Toxicology 1994 86 49 61. 

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... 

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... 

PBDEs including decabromodiphenyl ether, octabromodiphenyl ether, and pentabromodiphenyl ether are required to report health and safety data under the Toxic Substances Control Act (TSCA) (EPA 2002). 

PBDEs are commercially available as three products penta-, octa-, and deca-BDE. All of these products are mixtures of several congeners. The compositions of these three products, as measured in our laboratory at Indiana University, are given in Table 4. The penta-product contains primarily 2,2/,4,4/-tetrabromodiphenyl ether (BDE-47), 2,2, 4,4, 5-pentabromodiphenyl ether (BDE-99), and 2,2, 4,4, 6-pentabromodiphcnyl ether (BDE-100) in a ratio of about 7 10 2. The octa-product contains primarily 2,2, 3,4,4, 5, 6-heptabromodiphenyl ether (BDE-183), 2,2, 3,3, 4,4, 5,6 -... 

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... 

Analytes CB, chlorobenzenes DDE, l,l-dichloro-2,3-bis(4-chlorophenyl)ethane DDT, l,l-dichloro-2,3-bis(4-chlorophenyl)ethylene DBF, decabromobiphenyls HBCD, Hexabromo-cyclododecane HpBB, heptabromobiphenyl PBB, polybrominated biphenyl PBCCH, pentabromochlorocyclohexane PBDE, polybrominated diphenyl ether PBT, Polybutylene terephthalate PCB, Polychlorinated biphenyl PBDD, polybrominated dibenzo-/ -dioxins PBDF, polybrominated dibenzofuranes PCN, polychlorinated naphthalenes PCP, polychlorinated phenols PBB, polybrominated biphenyl PeBDE, pentabromodiphenyl ether PET, Polyethylene terephthalate PXDDs, polyhalogenated dibenzo-p-dioxins PXDFs, polyhalogenated dibenzofurans TBBPA, tetrabromobisphenol A TBPA, tetrabromophthalic anhydride TCBPA, tetrachlorobisphenol A TDBPP, tris(2,3-dibromopropyl)phosphate. 

Analytes. DBF, decabromobiphenyl HBCD, Hexabromocyclododecane PBCDE, polybrominated or chlorinated diphenyl ether PBDE, polybrominated diphenyl ether PCB, polychlorinated biphenyl PBDD, polybrominated dibenzo-p-dioxins PBB, polybrominated biphenyl PeBDE, pentabromodiphenyl ether. 

Meanwhile the shorter chain PBDEs have been found widely, particularly in the marine environment. However, the chairman of the BSEF has commented that the flame retardant industry has not and does not produce or use these shorter chain compounds in any large quantity. In fact recent studies show that pentabromodiphenyl ether (pentaBDE) was widely used by the mining and drilling industry in the 1980s and early 1990s as a hydraulic fluid, yet no one looks into these industries to explain the presence of these compounds in marine life. 

ATSDR has derived an MRL of 0.03 mg/kg/day for acute-duration oral exposure to PBDEs. The acute oral MRL is based on a NOAEL of 1 mg/kg/day for reduced serum levels of thyroid T, hormone in fetal rats that were exposed to octabromodiphenyl ether on days 4-20 of gestation (Zhou et al. 2002). ATSDR also derived an MRL of 0.007 mg/kg/day for intermediate-duration oral exposure to PBDEs. The intermediate oral MRL is based on a minimal LOAEL of 2 mg/kg/day for liver effects in rats that were exposed to pentabromodiphenyl oxide for 90 days (WIL Research Laboratories 1984). 

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