Filtern
Erscheinungsjahr
Dokumenttyp
Schlagworte
- Brominated flame retardant (3)
- Extraction (3)
- Chiral separation (2)
- HPLC-MS/MS (2)
- Mass spectrometry (2)
- Volatilome (2)
- A549 (1)
- APCI (1)
- Absolute configuration (1)
- Adsorption (1)
- Alcohol marker (1)
- Anomalous dispersion (1)
- Bewitterung (1)
- Bioisomerization (1)
- Breath (1)
- Cancer (1)
- Crystal structures (1)
- Derivatization (1)
- Diastereomers (1)
- Enantiomer fraction (1)
- Enantiomer-specific bioaccumulation (1)
- Enantiomer-specific determination (1)
- Enantiomers (1)
- Fish feeding experiment (1)
- Flame retardant (1)
- Flame retardants (1)
- Fortification (1)
- GCMS (1)
- Gas chromatography (1)
- HBCD (1)
- HPLC-DAD (1)
- HPLC-ESI-MS/MS (1)
- High-throughput analysis (1)
- Homogeneity (1)
- Indoor air (1)
- International intercomparison (1)
- Kinetics (1)
- LC-MS (1)
- Long term stability (1)
- Lung cancer cell culture (1)
- Marker (1)
- Measurement uncertainty (1)
- Micropulverization (1)
- Optical rotation (1)
- Polybrominated biphenyls (PBBs) (1)
- Polybrominated diphenyl ethers (PBDEs) (1)
- Polycyclic aromatic hydrocarbons (1)
- Polymer (1)
- Polyurethanes (1)
- Rearrangement (1)
- Reference materials (1)
- SPME (1)
- Schadstoffaustrag (1)
- Sediment (1)
- Sewage sludge (1)
- Solid phase microextraction (1)
- TBBPA-dbpe (1)
- Thermal degradation (1)
- Thermo-desorption (1)
- Umweltsimulation (1)
- VOC (1)
- Volatile organic compounds (1)
Organisationseinheit der BAM
- 1 Analytische Chemie; Referenzmaterialien (3)
- 1.7 Organische Spuren- und Lebensmittelanalytik (3)
- 4 Material und Umwelt (2)
- 1.1 Anorganische Spurenanalytik (1)
- 1.4 Prozessanalytik (1)
- 1.8 Umweltanalytik (1)
- 4.0 Abteilungsleitung und andere (1)
- 4.1 Biologische Materialschädigung und Referenzorganismen (1)
- 4.2 Material-Mikrobiom Wechselwirkungen (1)
- 4.3 Schadstofftransfer und Umwelttechnologien (1)
Gegenstand der vorzustellenden Arbeiten ist die Prüfung der Umwelt-beständigkeit und -verträglichkeit von Materialien und Produkten hinsichtlich der Emission von potenziellen Schadstoffen in die Umwelt. Hierzu werden chemisch-physikalische Einflüsse (Bewitterung) und mikrobielle Beanspruchungen an Modellmaterialien evaluiert. So werden die Freisetzungsraten von Schadstoffen in Abhängigkeit der Beanspruchung beschrieben. Als Modellmaterialien kommen die Polymere Polystyrol (PS) und Polypropylen (PP) zum Einsatz. Synergistische Effekte der Bewitterungsparameter und der mikrobiologischen Beanspruchung sollen dabei ebenso betrachtet werden, wie die gezielte Alterung. Auch findet eine Beschreibung des Verhaltens der ausgetragenen Schadstoffe in den Umweltkompartimenten Boden oder Wasser statt. Hier sind mit Hilfe der zu entwickelnden Screening- und non-Target-Analyseverfahren die Transformation und der Metabolismus durch Mikroorganismen zu beschreiben. Aus den Ergebnissen sollen Korrelationen zwischen den künstlichen Alterungsverfahren und realen Szenarien abgeleitet werden.
1,2,5,6,9,10-Hexabromocyclododecane (HBCD) is a widely used flame retardant, which tends to persist in the environment and accumulates in biota. The six stereoisomers (three racemates named α-, β-, and γ-HBCD) of the technical mixture were isolated with high-performance liquid chromatography (HPLC). Direct separations were performed on a chiral stationary phase containing permethylated -cyclodextrin (NUCLEODEX -PM column) and the pure enantiomers of α-, β-, and γ-HBCD were physically characterized for the first time. The absolute configurations of all six isomers were determined by anomalous dispersion using single crystal X-ray crystallography. Optical rotations αD in tetrahydrofuran were +4.2/-4.0 (α-HBCD), +26.1/-27.5 (β-HBCD), and +68.0/-66.3 (γ-HBCD). The sense of rotation could be correlated with the absolute configurations of α-, β-, and γ-HBCD enantiomers and their order of elution on a chiral permethylated β-cyclodextrin-bonded stationary phase. The diastereomers α-, β-, and γ-HBCD displayed distinctly different melting points as well as 1H-, 13C NMR, and IR spectra.
Stir bar sorptive extraction (SBSE) was compared with standardized pump sampling regarding the prospects to assess airborne levels of polycyclic aromatic hydrocarbons (PAHs) in indoor environments. A historic railway water tower, which will be preserved as a technical monument for museum purposes, was sampled with both approaches because the built-in insulationmaterial was suspected to release PAHs to the indoor air. The 16 PAHs on the US EPA list were quantified using gas chromatography with mass spectrometric detection in filters from pump sampling after solvent extraction and on SBSE devices after thermal desorption. SBSEwas seen to sample detectable PAHmasseswith excellent repeatability and a congener pattern largely similar to that observed with pump sampling. Congener patterns were however significantly different from that in the PAH source because release from the insulation material is largely triggered by the respective congener vapor pressures. Absolute masses in the ng range sampled by SBSE corresponded to airborne concentrations in the ng L−1 range determined by pump sampling. Principle differences between SBSE and pump sampling as well as prospects of SBSE as cost-effective and versatile complement of pump sampling are discussed.
The interconversion of the stereoisomers contained in technical 1,2,5,6,9,10-hexabromocyclododecane, a major brominated flame retardant increasingly found in the environment and in biota, was investigated at elevated temperatures. The application of pure enantiomers of the three constituents α-, β-, and γ-HBCD enabled the unambiguous elucidation of the individual isomerisation reactions as well as the quantification of all respective rate constants. At 160 °C the rate constants range over two orders of magnitude from 1.50 × 10-3 to 1.88 × 10-5 mol(%) s-1. A preliminary mechanistic explanation for the differences of the rate constants which govern the composition of HBCD diastereomers at equilibrium is given.