Investigation of the heterogeneity of bromine in plastic components as an indicator for brominated flame retardants in waste electrical and electronic equipment with regard to recyclability.

Waste electrical and electronic equipment (WEEE) can contain brominated flame retardants (BFRs) that pose a threat to human health and the environment. In addition, Br-containing plastics reduce the recycling potential of WEEE. In order to gain a better insight into the distribution of Br in plastics from WEEE, the total concentration of Br was measured on the level of device types and plastic components using handheld X-ray fluorescence (hXRF). In 35 % of the sample size (882 components from 369 different devices, which originate from 6 device types) Br was detected, 5 % exceeded the RoHS limit. Only few and older devices contained high Br concentrations, while the majority were below the RoHS limit and could be recycled. In addition, 18 different plastic types were identified by infrared spectroscopy, with acrylonitrile butadiene styrene being the most abundant (44 % of all samples). Manual dismantling of devices into individual plastic components enabled us to examine Br hotspots and the variety of plastic types in WEEE. Based on this analytical procedure, WEEE recyclers could exclude certain equipment or plastic components (e.g. power supplies or PC housings) directly on-site prior to WEEE recycling and shredding in order to produce high-quality recycled products and avoid cross-contamination.

Approaches to assess biocover performance on landfills.

Methane emissions from active or closed landfills can be reduced by means of methane oxidation enhanced in properly designed landfill covers, known as "biocovers". Biocovers usually consist of a coarse gas distribution layer to balance gas fluxes placed beneath an appropriate substrate layer. The application of such covers implies use of measurement methods and evaluation approaches, both during the planning stage and throughout the operation of biocovers in order to demonstrate their efficiency. Principally, various techniques, commonly used to monitor landfill surface emissions, can be applied to control biocovers. However, particularly when using engineered materials such as compost substrates, biocovers often feature several altered, specific properties when compared to conventional covers, e.g., respect to gas permeability, physical parameters including water retention capacity and texture, and methane oxidation activity. Therefore, existing measuring methods should be carefully evaluated or even modified prior to application on biocovers. This paper discusses possible strategies to be applied in monitoring biocover functionality. On the basis of experiences derived from investigations and large-scale field trials with compost biocovers in Austria, an assessment approach has been developed. A conceptual draft for monitoring biocover performance and recommendations for practical application are presented.

Changes in carbon and nitrogen pool during in-situ aeration of old landfills under varying conditions.

Emissions from old landfills via leachate and the gas phase are influenced by state and stability of the organic matter in the solid waste and by environmental conditions within the landfill. Remediation of landfills by means of in-situ aeration is one possibility to reduce these emissions. By establishing aerobic conditions, biological processes in the landfill are accelerated. To investigate the effects of this remediation technology, lab-scale experiments with column tests have been carried out. The main goal of the present work is to characterize the changes of the carbon and nitrogen compounds in the aerated solid waste, the leachate and the gas phase under varying conditions. The results demonstrate a clear reduction of emissions and a stabilization of the organic matter. Furthermore, it is shown that both the intensity of aeration and the amount of water affect biological processes to a certain extent. Even when columns were operated under anaerobic conditions after a long running period of aeration, the emissions remained low.

Small bowel tonometry is more accurate than gastric tonometry in detecting gut ischemia.

Gastric tonometer PCO2 measurement may help identify gut ischemia in critically ill patients but is frequently associated with large measurement errors. We tested the hypothesis that small bowel tonometer PCO2 measurement yields more accurate information. In 10 anesthetized, mechanically ventilated pigs subject to progressive hemorrhage, we measured gut oxygen delivery and consumption. We also measured tonometer PCO2 minus arterial PCO2 (DeltaPCO2) and calculated the corresponding intracellular pH from tonometers placed in the stomach and jejunum. We found that the correlation coefficient (r2) for biphasic gut oxygen delivery-DeltaPCO2 relationships was 0.29 +/- 0.52 for the gastric tonometer vs. 0.76 +/- 0.25 for the small bowel tonometer (P < 0.05). In addition, the critical gastric tonometer DeltaPCO2 was excessively high and variable (62.9 +/- 39.6) compared with the critical small bowel tonometer DeltaPCO2 (17.0 +/- 15.0, P < 0.01). Small bowel tonometer PCO2 was closely correlated with superior mesenteric vein PCO2 (r2 = 0.81, P < 0.001), whereas gastric tonometer PCO2 was not (r2 = -0.13, P = not significant). We conclude that measurement of gastric tonometer PCO2 yields excessively noisy and inaccurate data on the onset of gut anaerobic metabolism in hemorrhagic shock. Small bowel tonometer PCO2 is less noisy and, as a result, is superior in detecting gut hypoperfusion and the onset of anaerobic metabolism.

Heterogeneity of gut capillary transit times and impaired gut oxygen extraction in endotoxemic pigs.

We tested the hypothesis that endotoxin increases the heterogeneity of gut capillary transit times and impairs oxygen extraction. The gut critical oxygen extraction ratio was determined by measuring multiple oxygen delivery-consumption points during progressive phlebotomy in eight control and eight endotoxin-infused anesthetized pigs. In multiple 1- to 2-g samples of small bowel, we measured blood volume (radiolabeled red blood cells) and flow (radiolabeled 15-microns microspheres) before and after critical oxygen extraction. Red blood cell transit time (= volume/flow) multiplied by morphologically determined capillary/total blood volume gave capillary transit time. During hemorrhage, capillary/total blood volume did not change in the endotoxin group (0.5 +/- 4.5%) but increased in the control group (17.6 +/- 2.5%; P < 0.05) due to a decrease in total gut blood volume. Flow decreased significantly in the endotoxin group (36 +/- 10%; P < 0.05) but not in the control group (12 +/- 10%). Capillary transit-time heterogeneity increased in the endotoxin group (12.3 +/- 4.9%) compared with the control group (-5.8 +/- 7.4%; P < 0.05), predicting a critical oxygen extraction ratio 0.14 lower in the endotoxin group than in the control group (K. R. Walley. J. Appl. Physiol. 81: 885-894, 1996). This matches the measured difference (endotoxin group, 0.60 +/- 0.04; control group, 0.74 +/- 0.03; P < 0.05). Increased heterogeneity of capillary transit times may be an important cause of impaired oxygen extraction.

A comparative study on the performance of asbestos-free depth-filters for removal of pyrogens from infusion fluids.

Three asbestos-free depth-filters were compared with traditionally used asbestos-containing depth-filters for chemical integrity, physical integrity and pyrogen retention. With chemical and physical integrity only minor differences between the various filter types were seen. One asbestos-free depth-filter, based on charcoal, showed poor pyrogen-retention; this might be due to a high flow rate used. Asbestos-free depth-filters based on kieselguhr or on a mixture of kaolin and alumina proved to be good alternatives; these filters have proved to be suitable for the removal of pyrogens from electrolyte- or carbohydrate-containing infusion fluids.

[Use of herbal medicine in German children - prevalence, indications and motivation]. / Phytotherapie in der Kinderheilkunde - Prävalenz, Indikationen und Motivation.

BACKGROUND AND OBJECTIVES: Herbal medicine (phytotherapy) is increasingly used by the German population. But its use for children has been rarely analysed. This study determined prevalence, motivations and indications for the use of herbal medicine use. It also investigated parent-related variables associated with its use. METHODS: An anonymized questionnaire was filled in by parents of children and adolescents who attended the general pediatric out-patient department of two German university children's hospitals and the practice of two general pediatricians. RESULTS: 413 of 600 parents (68.8%) completed the questionnaire. Mean age of the children was 6.7 +/- 4.7 years. 353 (85.5%) were given one or more herbal products, chamomile (85.5%), fennel (81.3%), eucalyptus (43.9%). Bronchipret 43.1%) (thyme and primrose [tablets] or thyme with ivy [syrup] and Prospan (43.1%) (a syrup of ivy leaf extract) were the most commonly used, in the treatment of cough. Parents who give phytotherapeuticals to their children were significantly more often women, living in a large city, of good education and financially better off (p< 0.05). CONCLUSION: Herbal medicine is widely used in Germany during childhood and adolescence. To achieve high therapeutic safety it is important to ask parents explicitly about such use.

Selective shunting with EEG monitoring is safer than routine shunting for carotid endarterectomy.

The purpose of this study was to identify whether EEG is an adequate method of monitoring cerebral perfusion during carotid endarterectomy and of determining the need for use of an indwelling shunt. A retrospective review of 305 carotid endarterectomies comparing the results of routinely shunted patients with patients selectively shunted based on EEG monitoring, was carried out. Of the carotid endarterectomies, 92 (30%) were routinely shunted and 213 (70%) were selectively shunted. In the selectively shunted group, 34 (16%) subsequently required shunting. The major stroke rate in the routinely shunted group was 4.4% ((4) cases) and in the selectively shunted group was 0.5% ((1) stroke). Three of the four major strokes in the routinely shunted group were embolic in origin and one was caused by acute thrombosis. The only major stroke in the selectively shunted group was from intracerebral hemorrhage. In conclusion EEG monitoring is a safe and reliable method to determine the need for shunting during carotid endarterectomy. Routine non-selective use of a shunt may increase the risk of perioperative stroke from arterial injury and associated thromboembolism.