Analytical methods based on LC-ESI-MS/MS or LC-APPI-MS/MS were developed and/or validated for the separation and determination of BDE-209 and TBBP-A, in addition to HBCD diastereomers, enantiomers and degradation products in a wide range of samples including air, dust, diet, simulated GIT fluid, human serum and breast milk. The obtained concentrations were used to estimate the exposure of adults, toddlers and nursing infants to the target BFRs via inhalation, dust ingestion and diet using different exposure scenarios and the relative importance of each exposure pathway was assessed for the studied age groups. Causes of variability in concentrations of HBCDs in indoor dust were elucidated and forensic microscopy techniques were used to study the mechanisms of transfer of BDE-209 and HBCDs to indoor dust. A colon-enhanced physiologically based extraction model was developed and applied for the first time to study the bioaccessibility of target BFRs from human GIT. Exposure via dust ingestion, but not diet, correlated significantly (p<0.01) with ΣHBCDs in serum of 16 adults. The levels of target BFRs were reported for the first time in 28 human milk samples from the UK. The relationship between adult intake of BFRs and the observed body burdens was studied using a pharmacokinetic model. Although no enantioselective enrichment was detected in either dust or diet, enrichment of (-)-α-HBCD was observed in both human serum and milk which may be attributable to enantioselective absorption, metabolism and/or excretion.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:512381 |
| Date | January 2010 |
| Creators | Abdallah, Mohamed Abdel Galil Abou-Elwafa |
| Publisher | University of Birmingham |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://etheses.bham.ac.uk//id/eprint/546/ |
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