Analyse von polycyclischen aromatischen Kohlenwasserstoffen (PAK)

An interlaboratory test was organized by the Allgemeine Unfallversicherungsanstalt, Dept. HUB (Department for the Prevention of Occupational Accidents and Diseases) for the analysis of polycyclic aromatic hydrocarbons (PAH). The aim of the test was to compare analytical results of serveral laboratories performing PAH analysis as routine work. In a preliminary study four different PAH-containing solutions were analyzed by independent laboratories in Germany and Austria. The concentrations of 17 PAH (according to the relevant NIOSH-methods) were to be determined. The results reveal the problems involved in the analysis of PAH.     

Enzymatic production of biosilica glass using enzymes from sponges: basic aspects and application in nanobiotechnology (material sciences and medicine)

Biomineralization, biosilicification in particular (i.e. the formation of biogenic silica, SiO₂), has become an exciting source of inspiration for the development of novel bionic approaches following “nature as model”. Siliceous sponges are unique among silica forming organisms in their ability to catalyze silica formation using a specific enzyme termed silicatein. In this study, we review the present state of knowledge on silicatein-mediated “biosilica” formation in marine sponges, the involvement of further molecules in silica metabolism and their potential application in nanobiotechnology and medicine. Werner E. G. Müller dedicated this study to Prof. Vera Gamulin (Rudjer Boskovic Institute, Zagreb, Croatia) in honour of her unique contributions in molecular evolution.     

Dry and wet heat transfer through clothing dependent on the clothing properties under cold conditions.

The purpose of this study was to investigate the effect of moisture on the heat transfer through clothing in relation to the water vapour resistance, type of underwear, location of the moisture and climate. This forms part of the work performed for work package 2 of the European Union THERMPROTECT project. Thermal manikin results of dry and wet heat loss are presented from different laboratories for a range of 2-layer clothing with similar dry insulations but different water vapour permeabilities and absorptive properties. The results obtained from the different manikins are generally consistent with each other. For each climate, total wet heat loss is predominately dependent on the permeability of the outer layer. At 10 degrees C, the apparent evaporative heat loss is markedly higher than expected from evaporation alone (measured at 34 degrees C), which is attributed to condensation within the clothing and to increased conductivity of the wet clothing layers.     

Airborne trace element pollution in 11 European cities assessed by exposure of standardised ryegrass cultures

Within a European biomonitoring programme, Italian ryegrass (Lolium multiflorum Lam.) was employed as accumulative bioindicator of airborne trace elements (As, Cd, Cr, Cu, Fe, Ni, Pb, Sb, V, Zn) in urban agglomerations. Applying a highly standardised method, grass cultures were exposed for consecutive periods of four weeks each to ambient air at up to 100 sites in 11 cities during 2000–2002. Results of the 2001 exposure experiments revealed a clear differentiation of trace element pollution within and among local monitoring networks. Pollution was influenced particularly by traffic emissions. Especially Sb, Pb, Cr, Fe, and Cu exhibited a very uneven distribution within the municipal areas with strong accumulation in plants from traffic-exposed sites in the city centres and close to major roads, and moderate to low levels in plants exposed at suburban or rural sites. Accumulation of Ni and V was influenced by other emission sources. The biomonitoring sites located in Spanish city centres featured a much higher pollution load by trace elements than those in other cities of the network, confirming previously reported findings obtained by chemical analyses of dust deposition and aerosols. At some heavily-trafficked sites, legal thresholds for Cu, Pb, and V contents in foodstuff and animal feed were reached or even surpassed. The study confirmed that the standardised grass exposure is a useful and reliable tool to monitor and to assess environmental levels of potentially toxic compounds of particulate matter.     

Forecasting quantities of disused household CRT appliances--a regional case study approach and its application to Baden-Württemberg

Due to special requirements regarding logistics and recycling, disused cathode ray tube (CRT) appliances are handled in some countries as a separate waste fraction. This article presents a forecast of future household waste CRT quantities based on the past and present equipment of households with television sets and computer monitors. Additional aspects taken into consideration are the product life time distribution and the ongoing change in display technology. Although CRT technology is fading out, the findings of this forecast show that quantities of waste CRT appliances will not decrease before 2012 in Baden-Württemberg, Germany. The results of this regional case study are not quantitatively transferable without further analysis. The method provided allows analysts to consider how the time shift between production and discard could impact recycling options, and the method could be valuable for future similar analyses elsewhere.     

Phthalatkonzentrationen in Böden naturnaher Standorte des Sollings (Niedersachsen)

The phthalat concentrations in soil samples from the Solling (Ecological Research Project Solling) were measured. The samples were collected from a beech and a spruce forest and aTrisetum flavescens meadow. The distance from the tree trunks and the different horizons were taken into consideration as well. Dimethylphthalat, diethylphthalat, dibutylphthalat, butylbenzylphthalat, di-(2-ethylhexyl) phthalat and dioctylphthalat were determinated using GC/MS. From the six phthalates investigated, four were detected in the samples. Dimethyl and diethylphthalat were found at very low concentrations in only one sample. Dibutyl- and di-(2-ethylhexyl)phthalat were detected in eight of 21 samples. No phthalates were found in the samples from theTrisetum flavescens meadow. Two of the nine samples from the beech forest showed phthalates. In six of the nine samples from the spruce forest phthalates were detected. Phthalate concentrations in the spruce forest were always higher than those found in the beech forest.     

Linking local impacts to changes in climate: a guide to attribution

Assessing past impacts of observed climate change on natural, human and managed systems requires detailed knowledge about the effects of both climatic and other drivers of change, and their respective interaction. Resulting requirements with regard to system understanding and long-term observational data can be prohibitive for quantitative detection and attribution methods, especially in the case of human systems and in regions with poor monitoring records. To enable a structured examination of past impacts in such cases, we follow the logic of quantitative attribution assessments, however, allowing for qualitative methods and different types of evidence. We demonstrate how multiple lines of evidence can be integrated in support of attribution exercises for human and managed systems. Results show that careful analysis can allow for attribution statements without explicit end-to-end modeling of the whole climate-impact system. However, care must be taken not to overstate or generalize the results and to avoid bias when the analysis is motivated by and limited to observations considered consistent with climate change impacts.     

A linked model of animal ecology and human behavior for the management of wildlife tourism

Wildlife tourism attractions are characterized as having intricately coupled human-wildlife interactions. Accordingly, the ability to mitigate negative impacts of tourism on wildlife necessitates research into the ecology of the system and of the human dimensions, since plans aimed at optimizing wildlife fitness must also be acceptable to tourists. We developed an integrated systems dynamics model for the management of tourist-stingray interactions at ‘Stingray City Sandbar’ (SCS), Cayman Islands. The model predicts the state of the tourism attraction over time in relation to stingray population size, stingray life expectancy, and tourist visitation under various management scenarios. Stingray population data in the model comprised growth rates and survival estimates (from mark-and-recapture data) and mortality estimates. Inputted changes in their respective rates under different management scenarios were informed by previous research. Original research on the demand of heterogeneous tourist segments for management regulations via a stated choice model was used to calculate changes in the tourist population growth rate from data supplied by the Caymanian government. The management attributes to which tourists were responsive also have anticipated effects on stingray ecology (migration and mortality), and vice versa, thus linking the two components. We found that the model's predictions over a 25-year time span were sensitive to the stingray population growth rate and alternate management options. Under certain management scenarios, it was possible to maximize both the tourist segment in favor of no management and stingray numbers while reducing stingray health. However, the most effective relative strategy included a reduction in visitor density, restricted stingray interactions, and an imposition of a small fee. Over time, although fewer stingrays were predicted to remain at SCS, they would live longer and experience fewer stochastic disease events, and the desirable tourist segment was predicted to predominate. By understanding how management will affect tourist activities and their subsequent impacts on both wildlife health and visitor satisfaction, one can explore the management alternatives that would optimize both.