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Langen Brütz, Germany

Ibelings B.W.,University of Geneva | Backer L.C.,National Center for Environmental Health | Kardinaal W.E.A.,KWR Watercycle Research Institute | Chorus I.,German Federal Environment Agency
Harmful Algae | Year: 2014

Toxic cyanobacteria became more widely recognized as a potential health hazard in the 1990s, and in 1998 the World Health Organization (WHO) first published a provisional Guideline Value of 1μgL-1 for microcystin-LR in drinking-water. In this publication we compare risk assessment and risk management of toxic cyanobacteria in 17 countries across all five continents. We focus on the three main (oral) exposure vehicles to cyanotoxins: drinking-water, water related recreational and freshwater seafood. Most countries have implemented the provisional WHO Guideline Value, some as legally binding standard, to ensure the distribution of safe drinking-water with respect to microcystins. Regulation, however, also needs to address the possible presence of a wide range of other cyanotoxins and bioactive compounds, for which no guideline values can be derived due to insufficient toxicological data. The presence of microcystins (commonly expressed as microcystin-LR equivalents) may be used as proxy for overall guidance on risk management, but this simplification may miss certain risks, for instance from dissolved fractions of cylindrospermopsin and cyanobacterial neurotoxins. An alternative approach, often taken for risk assessment and management in recreational waters, is to regulate cyanobacterial presence - as cell numbers or biomass - rather than individual toxins. Here, many countries have implemented a two or three tier alert level system with incremental severity. These systems define the levels where responses are switched from Surveillance to Alert and finally to Action Mode and they specify the short-term actions that follow. Surface bloom formation is commonly judged to be a significant risk because of the elevated concentration of microcystins in a scum. Countries have based their derivations of legally binding standards, guideline values, maximally allowed concentrations (or limits named otherwise) on very similar scientific methodology, but underlying assumptions such as bloom duration, average body size and the amount of water consumed while swimming vary according to local circumstances. Furthermore, for toxins with incomplete toxicological data elements of expert judgment become more relevant and this also leads to a larger degree of variation between countries' thresholds triggering certain actions. Cyanobacterial blooms and their cyanotoxin content are a highly variable phenomenon, largely depending on local conditions, and likely concentrations can be assessed and managed best if the specific conditions of the locality are known and their impact on bloom occurrence are understood. Risk Management Frameworks, such as for example the Water Safety Plan concept of the WHO and the 'bathing water profile' of the European Union are suggested to be effective approaches for preventing human exposure by managing toxic cyanobacteria from catchment to consumer for drinking water and at recreational sites. © 2014 Elsevier B.V. Source

Rinn A.,Atelier | Berghahn R.,German Federal Environment Agency
Environmental Sciences Europe | Year: 2013

Artist Anne Rinn takes the reader on an excursion to an indoor and outdoor artificial pond and stream mesocosm system. This device was constructed and put into operation in 2001 in order to carry out scientific investigations concerning the aquatic environment, with the main focus on fate and effects of pollutants. Both technical features of the facility and the work and ideas for scientists and technicians were translated by her into an art exhibition which also included a film. This report on the project consists of two different text parts, one by the third author, who is an aquatic toxicologist, and one by the second author, an art historian. Their different backgrounds are reflected in different thinking and styles of expression. The text is rounded off by the photos of the first author, the artist. © 2013 Rinn et al.; licensee Springer. Source

Lagerlof J.,Swedish University of Agricultural Sciences | Adolfsson L.,Swedish University of Agricultural Sciences | Borjesson G.,Swedish University of Agricultural Sciences | Ehlers K.,German Federal Environment Agency | And 2 more authors.
Applied Soil Ecology | Year: 2014

This study investigates microbial communities in soil from sites under different land use in Kenya. We sampled natural forest, forest plantations, agricultural fields of agroforestry farms, agricultural fields with traditional farming and eroded soil on the slopes of Mount Elgon, Kenya. We hypothesised that microbial decomposition capacity, biomass and diversity (1) decreases with intensified cultivation; and (2) can be restored by soil and land management in agroforestry. Functional capacity of soil microbial communities was estimated by degradation of 31 substrates on Biolog EcoPlates™. Microbial community composition and biomass were characterised by phospholipid fatty acid (PLFA) and microbial C and N analyses. All 31 substrates were metabolised in all studied soil types, i.e. functional diversity did not differ. However, both the substrate utilisation rates and the microbial biomass decreased with intensification of land use, and the biomass was positively correlated with organic matter content. Multivariate analysis of PLFA and Biolog EcoPlate™ data showed clear differences between land uses, also indicated by different relative abundance of PLFA markers for certain microorganism groups. In conclusion, our results show that vegetation and land use control the substrate utilisation capacity and microbial community composition and that functional capacity of depleted soils can be restored by active soil management, e.g. forest plantation. However, although 20-30 years of agroforestry farming practises did result in improved soil microbiological and chemical conditions of agricultural soil as compared to traditional agricultural fields, the change was not statistically significant. © 2014. Source

Salthammer T.,Fraunhofer Institute for Wood Research, Wilhelm-Klauditz-Institut | Fauck C.,Fraunhofer Institute for Wood Research, Wilhelm-Klauditz-Institut | Schripp T.,Fraunhofer Institute for Wood Research, Wilhelm-Klauditz-Institut | Meinlschmidt P.,Fraunhofer Institute for Wood Research, Wilhelm-Klauditz-Institut | And 2 more authors.
Building and Environment | Year: 2011

The spontaneous discoloration of indoor surfaces which occurs especially during the heating period has been intensively investigated in Germany since the beginning of the 1990s. On the basis of earlier studies and a questionnaire this phenomenon, referred to as 'black dwellings' or 'black magic dust' (BMD), was attributed to the presence of semi-volatile organic compounds (SVOCs) and their interaction with dust and particles. In a project funded by the German Federal Environment Agency an attempt was made to deliberately simulate this effect in suitable test chambers. To do so wall paints were used which had been doped with the plasticizers DEHP and DBP. They were applied in different quantities to appropriate wall surfaces in four room size stainless-steel chambers. In this way realistic air concentrations of these two compounds were obtained. An artificially arranged thermal bridge located above a radiator was intended to accelerate deposition of the black dust. Even when the particle concentration in the chamber was briefly increased, no discoloration could be detected. It therefore appears that a combination of dust, thermal bridges and elevated concentrations of plasticizer does not necessarily trigger the BMD phenomenon. With the aid of investigations into affected dwellings it was possible to identify different mechanisms. Strong sources of particles were identified in some apartments while in others the particle deposits were caused by convective air flows. On the basis of all results it can be concluded that the deposition of particles by thermophoresis, diffusiophoresis or sedimentation is responsible for the phenomenon. © 2011 Elsevier Ltd. Source

Moser H.,German Federal Environment Agency | Roembke J.,ECT Oekotoxikologie GmbH | Donnevert G.,Justus Liebig University | Becker R.,BAM Federal Institute of Materials Research and Testing
Waste Management and Research | Year: 2011

The ecotoxicological characterization of waste is part of its assessment as hazardous or non-hazardous according to the European Waste List. For this classification 15 hazard criteria are derived from the Council Directive 91/689/EEC on hazardous waste. Some of the hazard criteria are based on the content of dangerous substances. The criterion H14 'ecotoxic' lacks of an assessment and testing strategy and no specific threshold values have been defined so far. Based on the recommendations of CEN guideline 14735 (2005), an international round robin test (ring test) was organized by the German Federal Environment Agency in order to define suitable test methods for the biological assessment of waste and waste eluates. A basic test battery, consisting of three aquatic and three terrestrial tests, was compiled. In addition, data were submitted for ten additional tests (five aquatic (including a genotoxicity test) and five terrestrial ones). The tests were performed with three representative waste types: an ash from an incineration plant, a soil containing high concentrations of organic contaminants (polycyclic aromatic hydrocarbons) and a preserved wood waste. The results of this ring test confirm that a combination of a battery of biological tests and chemical residual analysis is needed for an ecotoxicological characterization of wastes. With small modifications the basic test battery is considered to be well suitable for the hazard and risk assessment of wastes and waste eluates. All results and documents are accessible via a web-based data bank application. © The Author(s) 2011. Source

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