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- Hörsing, Maritha, 1970-, et al.
(författare)
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Investigation of the transformation potential of some ether derivatives of tetrabromobisphenol A and dimethyl ether of bisphenol A under methanogenic conditions
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- This study focused on transformation of the flame retardant tetrabromobisphenol A (TBBPA) and ether derivatives thereof during incubation under methanogenic conditions using landfill waste as inoculum. Bisphenol A dimethyl ether was also investigated in that context. Glass wool was placed in the incubation flasks to increase the surface area for adsorption of target compounds and thereby maximize exposure to the microbial population. A uniform analytical protocol for extraction of the silica surface and the aqueous phase was developed to suit all the targets. Overall recoveries were lowest for the dimethylated ethers and highest for TBBPA-dihydroxyethylether. TBBPA decreased to below detection limit within 35 days, but neither BPA nor the methyl ether of TBBPA was confirmed as a transformation product. The dimethylated ethers of BPA and TBBPA disappeared within 14 and 51 days, respectively, and BPA, but not TBBPA, proved to be a transformation product. No losses were observed for the most hydrophobic target TBBPA-dibromopropyl ether during the time frame of the transformation study (i.e., 51 days).
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| 2. |
- Hörsing, Maritha, 1970-, et al.
(författare)
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Leaching of Flame Retardants from products deposited in Landfills
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Materials in many products in daily use are amended with chemicals to give them desired properties, e.g. flame retardants (FRs) used to reduce the risks of products catching fire. However, potential risks posed by some of these chemicals, including FRs, to the environment and human health have raised concerns. Hence, there is a need for more knowledge regarding the fate of FRs, notably in landfills, where many FR-containing products are deposited. This article presents analyses of FRs and derivatives in leachates sampled during laboratory-scale simulations of landfills containing various FR-containing products progressing through typical landfill ageing phases. The FRs represented substances used both reactively, i.e. bound to the flame-protected material and additively, i.e. without any covalent bonding to the product.The phosphorus-based Pyrovatex-FR and the brominated tetrabromobisphenol A (TBBPA) were used to represent the reactive FRs, and the nitrogen-based melamine and phosphorus-based FR of Proban the additive FRs. Residual FRs from the treatment of the materials were probably the main contributors to the leachates from all products. Their durability, i.e. ability to withstand laundry washes, was reflected in their leaching abilities, while the different landfill conditions were of minor importance, except for melamine (of which approximately 10% of the amount present in the test product leached and mineralised to carbon dioxide and ammonia, mainly during the period when the landfill models passed from acidogenic to methanogenic conditions). The other additively applied FR in Proban leached first during the later part of the incubation (between 80 and 112 weeks), in accordance with its laundry resistance. Substantial proportions of the residual chemicals in Pyrovatex-treated materials are generally lost during the first washing. Accordingly, early losses of the chemicals used in this treatment were detected during the landfill simulation. Elevated phosphate concentrations were also detected in simulations with the Pyrovatex- and Proban-treated products, suggesting that the FRs generated in these treatments were degraded during or after release to the leachate. Small amounts of TBBPA were observed at the end of the incubation, and no TBBPA degradation products were observed, but debromination (which is likely to occur during anoxic stages) would lead to the formation of bisphenol A.
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| 3. |
- Jonsson, Susanne, 1965-, et al.
(författare)
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Investigation of sorption phenomena by solid-phase extraction and liquid chromatography for determination of some ether derivatives of tetrabromobisphenol A
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Observed sorption and chromatographic behaviour served as a starting point for examination of four ether derivatives of the flame retardant tetrabromobisphenol (TBBPA). To date, there is little or no information about these compounds in the scientific literature. The targets in the present study had calculated log Kow values of 6.0–10, indicating a rather hydrophobic nature. A broad range of different types of solvents were used in order to elucidate the mechanisms of sorption on one hydrophilic surface (silica) and two hydrophobic surfaces (polystyrene divinylbenzene polymers). Also, three chromatographic columns (C18, C8, and dual C18-based) were evaluated. In general, the most hydrophilic and the most hydrophobic derivatives (dihydroxyethyl- and di(2,3-bromopropyl), respectively) were more easily desorbed from the studied surfaces by the selected solvents.Regardless of the experimental test conditions applied, the lowest recovery was seen for dimethoxy-TBBPA, followed by TBBPA itself. Also, this study claims that the polar character of the dual-phase column was not as pronounced as asserted by the manufacturer.
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