Diphenylethers polybrominated

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... 

Danon-Schaffer MN (2010) Polybrominated diphenylethers in landfills from electronic waste. Faculty of graduate studies (chemical and biological engineering). Vancover, The University of British Columbia. Dr. phil 362... 

Takasuga T, Senthilkumar K, Takemori H, Ohi E, Tsuji H, Nagayama J (2004) Impact of fermented brown rice with Aspergillus oryzae (FEBRA) intake and concentrations of polybrominated diphenylethers (PBDEs) in blood of humans from Japan. Chemosphere 57 795-811... 

Allchin CR, Law RJ, Morris S (1999) Polybrominated diphenylethers in sediments and biota downstream of potential sources in the UK. Environ Pollut 105 197-207... 

Industrial organic pollutants Perfluorinated compounds (PFCs), polybrominated diphenylethers (PBDEs), new pesticides, and nanomaterials. 

Keywords Biotoxins, Coccidiostats, Food contaminants, LC-MS/MS, Nanomaterials antibiotics, Perfluorinated compounds. Pesticides, Polybrominated diphenylethers... 

The emerging pollutants also include perfluorooctanoic acid (PFOA) and perfluorooctanesul-fonate (PFOS), used in the production of water-resistant coatings and polybrominated diphenylether (PBVDF) that find application in furniture, textiles, plastics, and paint industries. Due to their large industrial use, these chemicals are present profusely in the environment and also in the blood of people working in the fields [21]. 

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. 

Meerts I, Lujiks E. Marsh G, et al. 1988. Polybrominated diphenylethers (PBDEs) as Ah-receptor agonists and antagonists. Organohalogen Compounds 37 147-150. 

Tysklind M, Sellstom U, Soderstrom G, et al. 2001. Abiotic transformation of polybrominated diphenylethers (PBDEs) Photolytic debromination of decambro diphenyl ether. BFR 51-54. 

Wong A, Duan Lei Y, Alaee M, et al. 2001. Vapor pressure of the polybrominated diphenylethers. 

Polychlorinated Dibenzo-(p)-Dioxins and Dibenzo-Furans. Another group of compounds that we need to specifically address are the polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzo-furans (PCDFs) (Fig. 2.15). The PCDDs and PCDFs are not intentionally produced but are released into the environment from various combustion processes and as a result of their occurrence as unwanted byproducts in various chlorinated chemical formulations (e.g., chlorinated phenols, chlorinated phenoxy herbicides see Alcock and Jones, 1996). Because some of the PCDD and PCDF congeners are very toxic (e.g., 2,3,7,8-tetrachloro dibenzo-p-dioxin, see margin), there have been and still are considerable efforts to assess their sources, distribution, and fate in the environment. Similarly to the PCBs or DDT (see above), the PCDDs and PCDFs are highly hydrophobic and very persistent in the environment. It is therefore not surprising that they have also been detected everywhere on earth (Brzuzy and Hites, 1996 Lohmann and Jones, 1998 Vallack et al., 1998). Finally, we should note that polybrominated diphenylethers (PBDEs, see margin) that, like the PBBs (see above), are used as flame retardants, are of increasing environmental concern (de Boer et al., 2000). 

Pettersson A, van Bavel B, Engwall M, Jimenez B (2004) Polybrominated Diphenylethers and Methoxylated Tetrabromodiphenylethers in Cetaceans from the Mediterranean Sea. Arch Environ Contam Toxicol 47 542... 

A very simple HF-MMLLE configuration has been employed by flame-sealing the two ends of the HFs. The HFs were then soaked in n-undecane for a period of time so as to allow them to fill with solvent this makes simple HF-MMLLE devices. In this way, a single HF was utilized for the MMLLE of eight polybrominated diphenylethers (PBDEs) in 100 mL samples of tap, river, and leachate water. The analysis was done by manual injection of 2 pL of the HF lumen content into a splitless GC injector followed by GC-MS analysis in selected ion monitoring (SIM) mode. Under optimal HF-MMLLE conditions, the extraction was exhaustive (E = 57-104%), giving very good enrichment (Ee = 2800-5200-fold), very low LOD (<1.1 ng I. ), and relative recoveries of 85-110%. Two PBDEs were detected and quantified in leachate water at concentrations of 3.5 ng I. for BDE 153 and 23 ng L 1 for BDE 183.96... 

The toxicity, bioaccumulative potential, and ecological impact of organohalogenated substances such as polychlorinated biphenyls (PCBs), polychlorinated dibenzofurans (PCDFs), polychlorinated d iben zo -pa ra - diox i n s (PCDDs), or polybrominated diphenylethers (PBDEs) have been extensively reviewed.95 98 All are referred to as persistent organic pollutants (POPs), that is, chemical substances that remain in the environment, bioaccumulate through the food chain, and pose a risk to human health and the environment. The international community is calling for action to reduce and then eliminate the production or formation of these substances and to monitor their emission. In this case, the detectability obtainable by analytical methods should be very low, since the limits established for these residues are in the ng per liter range. 

U.S. EPA (Environmental Protection Agency). 2008. Polybrominated diphenylethers (PBDEs). Available at http //www.epa.gov/oppt/pbde/. 

Barring, H., Bucheli, T.D., Broman, D., Gustafsson, 6. (2002) Soot-water distribution coefficients for polychlorinated dibenzo-/ -dioxins, polychlorinated dibenzofurans and polybrominated diphenylethers determined with the soot cosolvency-column method. Chemosphere 49, 515-523. 

The European Union has been quite visible in recent years with such directives. RoHS (Restriction in the use of Hazardous Substances), WEEE (Waste of Electrical and Electronic Equipment), and REACH (Registration, Evaluation, Authorization, and Restriction of Chemical substances). RoHS places restrictions on use of lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls, and some polybrominated diphenylethers. WEEE targets responsible recycling of electronic equipment. REACH is a new European Community Regulation on chemicals and their safe use... 

Buser HR (1986), Environ. Sci. Technol. 20 404-408. Polybrominated dibenzofurans and dibenzo-p-dioxins Thermal reaction products of polybrominated diphenylether flame retardants"... 

The most frequently used BFRs are polybrominated diphenylethers (PBDEs), tetrabromobisphenol A (TBBPA), and hexabromocyclododecane (HBCD). The use of FRs has been growing rapidly in recent years. BFRs are the most often used FRs, and their market is still growing. However, the estimated annual use of OPFRs in Western Europe was almost twice that of all BFRs combined. Many FRs have been banned for use because of their potential toxicity, environmental occurrence, and accumulation in human tissue. FRs taken off the market are likely to be replaced by others. Although the REACH (registration, evaluation, authorization and restriction of chemicals) regulatory system has been introduced in Europe to improve protection of human health and the environment, it is still necessary to monitor FRs in environmental samples [84, 88]. 

Table 15. Chemical name, trade name, CAS No., chemical structure, molecular formula, molecular weight, n-octanol/water partition coefficient (Kqw), bioconcentration factors on a lipid basis (BCFl) in fish, and residues found in environmental samples (sediments, mussels, fish) and human fat of Polybrominated Benzenes (PBBzs), Polybrominated Biphenyls (PBBs), and Polybrominated Diphenylethers (PBDEs)... 

Keywords, Polybrominated biphenyl, Polybrominated diphenylether, Production, Analytical methods, Environmental, distribution, Toxicity... 

Polybrominated biphenyls (PBBs) and polybrominated diphenylethers (PBDEs) are aromatic hydrocarbons, which are used as flame retardants. Flame retardants are chemicals that are added to polymers which are used in different... 

Leppanen, M, Kukkonen, J.W.K. (2004) Toxicokinetics of sediment-associated polybrominated diphenylethers (flame retardants) in benthic invertebrates (Lumbriculus variegatus, oligochaeta). Environ. Toxicol. Chem. 23, 166-172. 

Fig. 4 Molecular structures of 1 - Polybrominated naphthalenes, PBNs, 2 -Tetrachlorobenzyltoluenes, TCBTs, 3 - Polybrominated diphenylethers, PBDEs, 4 - Polychlorinated terphenyls, PCTs, 5 - Polychlorinated triphenylmethanes, PCTPM, 6 - Polychlorinated dibenzothiophenes, PCDBT.

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