Causes of variability in concentrations and diastereomer patterns of hexabromocyclododecanes in indoor dust

The temporal evolution of concentrations of α-, β-, and γ-hexabromocyclododecanes (HBCDs), and pentabromocyclododecenes (PBCDs — degradation products of HBCDs) was studied in separate aliquots of a well-homogenized indoor dust sample. These were: (a) exposed to natural light, and (b) kept in the dark. Results revealed a rapid photolytically-mediated shift from γ-HBCD to α-HBCD that was complete after 1 week of exposure, and a slower degradative loss of HBCDs via elimination of HBr. Under the specific conditions studied in this experiment, calculated half-lives (t_1/2) showed the decay in ΣHBCDs concentration was faster in light-exposed samples (t_1/2 = 12 weeks), than in light-shielded dust (t_1/2 = 26 weeks). Within-room spatial and temporal variability in concentrations and diastereomer patterns were studied in six and three rooms respectively. While in some rooms, little variability was detected, in others it was substantial. In one room, concentrations of ΣHBCDs and the relative abundance of γ-HBCD declined dramatically with increasing distance from a TV. The same TV appears to have influenced strongly the temporal variation in that room; with higher concentrations observed in its presence and when the TV was moved closer to the area sampled. Significant negative correlation was observed in one room between concentrations of ΣHBCDs and dust loading (g dust m^? 2 floor), implying “dilution” occurs at higher dust loadings.     

Novel brominated flame retardants: a review of their analysis, environmental fate and behaviour

This review summarises current knowledge about production volumes, physico-chemical properties, analysis, environmental occurrence, fate and behaviour and human exposure to the "novel" brominated flame retardants (NBFRs). We define the term NBFRs as relating to BFRs which are new to the market or newly/recently observed in the environment. Restrictions and bans on the use of some polybrominated diphenyl ether (PBDE) formulations, in many jurisdictions, have created a market for the use of NBFRs. To date, most data on NBFRs have arisen as additional information generated by research designed principally to study more "traditional" BFRs, such as PBDEs. This has led to a wide variety of analytical approaches for sample extraction, extract purification and instrumental analysis of NBFRs. An overview of environmental occurrence in abiotic matrices, aquatic biota, terrestrial biota and birds is presented. Evidence concerning the metabolism and absorption of different NBFRs is reviewed. Human exposure to NBFRs via different exposure pathways is discussed, and research gaps related to analysis, environmental sources, fate, and behaviour and human exposure are identified.     

Context change and travel mode choice: Combining the habit discontinuity and self-activation hypotheses

The habit discontinuity hypothesis states that when a context change disrupts individuals’ habits, a window opens in which behavior is more likely to be deliberately considered. The self-activation hypothesis states that when values incorporated in the self-concept are activated, these are more likely to guide behavior. Combining these two hypotheses, it was predicted that context change enhances the likelihood that important values are considered and guide behavior. This prediction was tested in the domain of travel mode choices among university employees who had recently moved versus had not recently moved residence. As was anticipated, participants who had recently moved and were environmentally concerned used the car less frequently for commuting to work. This was found not only when compared to those who were low on environmental concern (which would be a trivial finding), but also to those who were environmentally concerned but had not recently moved. The effects were controlled for a range of background variables. The results support the notion that context change can activate important values that guide the process of negotiating sustainable behaviors.     

Non-destructive pollution exposure assessment in the European hedgehog (Erinaceus europaeus): IV. Hair versus soil analysis in exposure and risk assessment of organochlorine compounds

Few ecotoxicological studies on mammals use non-destructive methodologies, despite the growing ethical concern over the use of destructive sampling methods. In the present study we assessed exposure of hedgehogs (Erinaceus europaeus) to polychlorinated biphenyls (PCBs), dichloro-diphenyl-trichloroethanes (DDTs), hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB), by investigating concentrations of these compounds in soils and hedgehog hair from seven study sites around the urban area of Antwerp, Belgium. No relationships were observed between organochlorine compound concentrations in soils and hair from the different study areas. Furthermore, the individual variation of contamination levels in hair within study sites was high, especially for HCHs and HCB, and hair and soil had different relative profiles for PCBs, DDTs and HCHs. Our results show that concentrations of organochlorine compounds in soils alone are not predictive of the risk of these pollutants to hedgehogs and that tissue analyses are preferred to soil analyses in exposure and risk assessment studies.     

Duplication of chromosome 2 in association with ventriculomegaly — a case report

This is a case report of the prenatal diagnosis of a de novo interstitial duplication of chromosome 2 (46,XX,dup(2)(p13p21) de novo) with an associated phenotypic abnormality. This chromosomal duplication is rare, only one has previously been described prenatally. Postnatal reports of similar duplications in this region have described associated dysmorphic features and significant neurodevelopmental delay. In our case, the only ultrasound finding was moderately severe ventriculomegaly. At post-mortem, ventriculomegaly was confirmed and there was associated macrocephaly (head circumference above the 97th centile) with no dysmorphic features seen. Copyright © 2001 John Wiley & Sons, Ltd.