Polybrominated dibenzofurans

Loganathan BG, Kannn K, Watanabe, et al. 1995. Isomer-specific determination and toxic evaluation of polychlrinated biphenyls, polychlorinated/brominated dibenzo-p-dioxins and dibenzofurans, polybrominated biphenyl ethers, and extractable organic halogen in carp from the Buffalo River, New York. Environ Sci Technol 29(7) 1832-1838. 

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. 

Eljarrat E, De La Cal A, Larrazabal D, Fabrellas B, Femandez-Alba AR, Borrull F, Marce RM, Barcelo D (2005) Occurrence of polybrominated diphenylethers, polychlorinated dibenzo-p-dioxins, dibenzofurans and biphenyls in coastal sediments from Spain. Environ Pollut 136(3) 493-501... 

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]. 

Table 1 Concentrations of chlorinated polycyclic aromatic hydrocarbons (CIPAHs), polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), polybrominated biphenyls (PBBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) in ambient air, soil, and human samples collected from e-waste recycling and reference sites in China... 

Wen S, Yang F, Li JG, Gong Y, Zhang XL, Hui Y, Wu YN, Zhao YF, Xu Y (2009) Polychlorinated dibenzo-p-dioxin and dibenzofurans (PCDD/Fs), polybrominated diphenyl ethers (PBDEs), and polychlorinated biphenyls (PCBs) monitored by tree bark in an e-waste recycling area. Chemosphere 74(7) 981-987. doi 10.1016/j.chemosphere.2008.10.002... 

H. Thoma, G. Hauschulz, E. Knorr and O. Hutzinger, "Polybrominated Dibenzofurans (PBDF) and Dibenzodioxins (PBDD) from the Pyrolysis of Neat Brominated Diphenylethers, Biphenyls and Plastic Mixtures of these Compounds,"Chemosphere, JJi, 277(1987). 

Fig. 7 Generic chemical structures of polyhalogenated compounds. X=C1, Br. (I) Polychlorinated biphenyls (PCBs), polybrominated biphenyls (PBBs) (II) chlorophenols (CPs), bromophenols (BPs) (III) polychlorinated diphenyl ethers (PCDE), polybrominated diphenyl ethers (PBDE) (IV) polychlorinated dibenzo-p-dioxin (PCDD), polybrominated dibenzo-p-dioxin (PBDD) (V) polychlorinated dibenzofuran (PCDF), polybrominated dibenzofuran (PBDF) (VI) tetrabromobisphenol A (TBBPA)...

WHO/ICPS (1998) Environmental Health Criteria 205 polybrominated dibenzo-p-dioxins and dibenzofurans. World Health Organization, Geneva... 

Polybrominated biphenyls (No. 152,1994) Polybrominated dibenzo-p-dioxins and dibenzofurans (No. 205,1998) Polychlorinated biphenyls and terphenyls (No. 2,1976,1st edition) ... 

Pyrolysis of FireMaster BP-6 in the temperature range of 600 900 °C in the absence of oxygen produced bromobenzenes and brominated biphenyls as key products, but no brominated dioxins and dibenzofurans (Thoma and Hutzinger 1987 Thoma et al. 1987). Thermolysis of Hi re Mast a- BP-6 between 400 and 600 °C in the presence of air produced 23,7,8-tetrabromodibenzofuran in the percent ( 1 %10 g/kg) range (Rappe and Buser 1980). Pyrolysis of FireMaster BP-6 in an open quartz tube at 800 °C produced 0.48 1.49 gZkg2,3,7,8-TCDD equivalent levels of polybrominated dibenzofurans (Zacharewski et al. 

When pyrolysed up to 900 °C, PBDEs release polybrominated dibenzofurans (PBDEs) and... 

Approximately 11.8 million pounds of hexabromobiphenyl were used in commercial and consumer products in the United States, most in the production of plastic products with an estimated use life of 5 10 years (Neufeld et al. 1977). Since the cessation of production, all of these products, such as TV cabinet and business machine housings, must have been disposed ofby land filling or incineration (Neufeld et al. 1977). The formation of polybrominated dioxins (PBDDs) and polybrominated dibenzofurans (PBDFs) during the incineration of plastics containing PBBs remains a distinct possibility (Luijk and Covers 1992 O Keefe 1978). 

It would be helpful to develop data determining the accuracy of PBDE determinations (e.g., percent recovery) in environmental samples. Methods for determining degradation products and metabolites of PBDE are needed. There is no information in the literature of detectable biodegradation of PBDEs in the environment under aerobic or anaerobic conditions. The analysis of PBDE pyrolysis degradation products, such as polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs), is often disturbed by the presence of PBDEs. Ebert et al. (1999) demonstrated that by using a Florisil column ina sample clean-up process, almost complete separation of PBDEs and PBDD/Fs is achieved before analysis by GC-MS. 

Cramer PH, Ayling RE, Thornburg KR, et al. 1990. Evaluation of an analytical method for the determination of polybrominated dibenzo-p-dioxins/dibenzofurans (PBDD/PBDF) in human adipose. Chemosphere 20(7-9) 821-827. 

Dumler R, Thoma H, Lenoir D, et al. 1989b. Thennal formation of polybrominated dibenzodioxins (PBDD) and dibenzofurans (PBDF) from bromine containing flame retardants. Chemosphere 19(l-6) 305-308. 

Dumler-Gradl R, Tartler D, Thoma H, et al. 1995. Detection of polybrominated diphenylethers (PBDE), dibenzofurans (PBDF) and dibenzodioxins (PBDD) in scrap of electronics and recycled products. Organohalogen Compounds 24 101-104. 

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. 

Lutes CC, Charles MJ, Odum JR, et al. 1992. Chamber aging studies on the atmospheric stability of polybrominated dibenzo-p-dioxins and dibenzofurans. Environ Sci Technol 26(5) 991-998. 

Mennear JH, Lee C-C. 1994. Polybrominated dibenzo-p-dioxins and dibenzofurans literature review and health assessment. Environ Health Perspect Suppl 102 265-274. 

O Keefe PW. 1978. Fonnation of brominated dibenzofurans from pyrolysis of the polybrominated biphenyl fire retardant, Firemaster FF-1. Environ Health Perspect 23 347-350. 

Thoma H, Hauschulz G, Knorr E, et al. 1987. Polybrominated dibenzofurans (PBDF) and... 

The cellular slime mold Dictyostelium purpureum K1001 contains AB0022A (2255), a novel antibacterial dibenzofuran, the structure of which was confirmed by total synthesis (2038). The lichen Lecanora cinereocarnea has yielded several new dibenzofurans, including three chlorinated analogues (2256-2258) (2039), and Lecanora iseana contains 2259 and 2260 (2040). The first naturally occurring polybrominated dibenzofuran, corallinafuran (2261), is present in a crustose coralline red alga that also contains corallinaether (1913) cited earlier (1769). 

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