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Hilt S.,Leibniz Institute of Freshwater Ecology and Inland Fisheries | Van De Weyer K.,Lanaplan | Kohler A.,Environment and Consumer Protection | Chorus I.,German Federal Environmental Agency
Restoration Ecology | Year: 2010

Eutrophication of two urban temperate dimictic lakes in Berlin (Germany), smaller Schlachtensee (0.4 km 2) and larger Lake Tegel (3 km 2), caused total phosphorus (TP) concentrations up to 800 μg/L and a complete loss of their diverse submerged vegetation in the 1960s due to poor light conditions. Phosphorus stripping of their inflow began in the 1980s and caused a pronounced decline of their epilimnetic TP concentrations, eventually leading to reduced phytoplankton biomass and turbidity. Despite increased light availability, recovery of abundance as well as species diversity of submerged macrophytes was delayed by more than a decade, especially in the smaller lake. Slow oxidization of sapropelic sediment unsuitable for macrophyte growth, periphyton shading, herbivory, and/or lack of a viable seed bank were potential hampering factors. The present submerged vegetation, however, may already support mechanisms positively influencing water transparency such as providing habitat to enhance the ratio of piscivorous to planktivorous fish. Characeae meadows, typical for both lakes during their former mesotrophic state, so far only reoccurred in smaller Schlachtensee. Neither species composition nor abundance reversed back to the macrophyte community present in the nineteenth century. Although TP concentrations may decline further and some rare species have been detected, reassembly of this plant community will most probably not occur because many submerged macrophyte species have become rare throughout northwest Europe. © 2009 Society for Ecological Restoration International.

Koller V.J.,Medical University of Vienna | Ferk F.,Medical University of Vienna | Al-Serori H.,Medical University of Vienna | Misik M.,Medical University of Vienna | And 4 more authors.
Food and Chemical Toxicology | Year: 2015

Synthetic cannabinoids (SCs) cause similar effects as cannabis and are sold in herbal mixtures. Recent investigations indicate that some of these drugs possess genotoxic properties. Therefore, we tested representatives of two groups, namely, aminoalkylindoles (AM-2201 and UR-144) and 1-alkylindazoles (5F-AKB-48 and AM-2201-IC) in single cell gel electrophoresis and micronucleus (MN) assays with human lymphocytes and in Salmonella/microsome assays. All drugs except AM-2201 caused DNA-migration, the LOELs were between 50 and 75 μM. Furthermore, all SCs caused inhibition of cell division and significant induction of MN which reflect structural and numerical chromosomal aberrations. The LOEL values were 50 μM for UR-144 and 5-AKB-48 and 75 μM for the other drugs. Also the levels of nucleoplasmatic bridges which are formed from dicentric chromosomes were elevated under identical conditions while the frequencies of nuclear buds were not affected. These findings show that representatives of both groups cause chromosomal damage while the negative results in Salmonella assays (in strains TA98, TA100, TA1535, TA1537 and TA102) in absence and presence of metabolic activation indicate that they do not induce gene mutations. Taken together, these findings indicate that SCs may cause adverse health effects in users as a consequence of damage of the genetic material. © 2015 Elsevier Ltd.

Hahn S.,Fraunhofer Institute for Toxicology and Experimental Medicine | Schneider K.,Research and Advisory Institute for Hazardous Substances GmbH FoBiG | Gartiser S.,Hydrotox GmbH | Heger W.,German Federal Environmental Agency | Mangelsdorf I.,Fraunhofer Institute for Toxicology and Experimental Medicine
Environmental Health: A Global Access Science Source | Year: 2010

Background. Products containing biocides are used for a variety of purposes in the home environment. To assess potential health risks, data on products containing biocides were gathered by means of a market survey, exposures were estimated using a worst case scenario approach (screening), the hazard of the active components were evaluated, and a preliminary risk assessment was conducted. Methods. Information on biocide-containing products was collected by on-site research, by an internet inquiry as well as research into databases and lists of active substances. Twenty active substances were selected for detailed investigation. The products containing these substances were subsequently classified by range of application; typical concentrations were derived. Potential exposures were then estimated using a worst case scenario approach according to the European Commission's Technical Guidance Document on Risk Assessment. Relevant combinations of scenarios and active substances were identified. The toxicological data for these substances were compiled in substance dossiers. For estimating risks, the margins of exposure (MOEs) were determined. Results. Numerous consumer products were found to contain biocides. However, it appeared that only a limited number of biocidal active substances or groups of biocidal active substances were being used. The lowest MOEs for dermal exposure or exposure by inhalation were obtained for the following scenarios and biocides: indoor pest control using sprays, stickers or evaporators (chlorpyrifos, dichlorvos) and spraying of disinfectants as well as cleaning of surfaces with concentrates (hydrogen peroxide, formaldehyde, glutardialdehyde). The risk from aggregate exposure to individual biocides via different exposure scenarios was higher than the highest single exposure on average by a factor of three. From the 20 biocides assessed 10 had skin-sensitizing properties. The biocides isothiazolinone (mixture of 5-chloro-2-methyl-2H-isothiazolin-3-one and 2-methyl-2H-isothiazolin-3-one, CMI/MI), glutardialdehyde, formaldehyde and chloroacetamide may be present in household products in concentrations which have induced sensitization in experimental studies. Conclusions. Exposure to biocides from household products may contribute to induction of sensitization in the population. The use of biocides in consumer products should be carefully evaluated. Detailed risk assessments will become available within the framework of the EU Biocides Directive. © 2010 Hahn et al; licensee BioMed Central Ltd.

Langer J.,University Hospital Frankfurt | Penna-Martinez M.,University Hospital Frankfurt | Wallasch M.,German Federal Environmental Agency | Bon D.,Goethe University Frankfurt | Badenhoop K.,University Hospital Frankfurt
Journal of Steroid Biochemistry and Molecular Biology | Year: 2013

Background: Type 1 diabetes (T1D) is an autoimmune disease which is characterised by the destruction of insulin-producing beta cells in human pancreas leading consequently to a hyperglycaemic metabolism. Recent studies have shown that low cholecalciferol (25(OH)D3) concentrations may contribute to the development of T1D. The 25(OH)D3 status depends mostly on human skin production influenced by exposure to UVB radiation. Our intention was to examine whether there was a change in UVB radiation in the past years and if this has an impact on patients' vitamin D status. Methods: We analysed the 25(OH)D3 concentration of blood samples from 287 T1D patients in the years 2004-2007 at the University Hospital Frankfurt. Moreover, daily UVB irradiation data of this time were received. Wilcoxon-Mann-Whitney test and Spearman correlation test were used for statistical analyses. Results: We observe a strong correlation between UVB irradiation and the 25(OH)D 3 concentration of German T1D patients (correlation coefficient = rho = 0.56, p = 7 × 10-3). Moreover, 25(OH)D3 blood levels obtained in summer (Apr-Oct) were significantly higher than in the winter season (p = 8 × 10-3). In the years 2004-2007 there was a significant decline of UVB radiation in the summers (rho = -0.21, p < 10 -6) but no change was found in (rho = -0.07, p = 0.12). This corresponds to a significant decrease of 25(OH)D3 levels in T1D patients over the summers (rho = -0.24, p = 2 × 10-3) but not in winters (rho = -0.03, p = 0.73). Conclusion: Our results reveal a significant correlation of UVB irradiation and the vitamin D concentration of German T1D patients. A decrease of UVB irradiation over the summers 2004-2007 is accompanied by a decline of 25(OH)D3 levels observed in those summer months which may indicate a local time trend requiring further investigation into the environmental factors of vitamin D deficiency. This article is part of a Special Issue entitled 'Vitamin D Workshop'. © 2012 Elsevier Ltd. All rights reserved.

Wagener S.,Humboldt University of Berlin | Wagener S.,German Federal Environmental Agency | Wagener S.,German Federal Institute for Risk Assessment | Langner M.,German Federal Environmental Agency | And 3 more authors.
Atmosphere | Year: 2014

The elemental carbon (EC)-tracer method was applied to PM10 and PM1 data of three sampling sites in the City of Berlin from February to October 2010. The sites were characterized by differing exposure to traffic and vegetation. The aim was to determine the secondary organic carbon (SOC) concentration and to describe the parameters influencing the application of the EC-tracer method. The evaluation was based on comparisons with results obtained from positive matrix factorization (PMF) applied to the same samples. To obtain site-and seasonal representative primary OC/EC-ratios ([OC/EC]p), the EC-tracer method was performed separately for each station, and additionally discrete for samples with high and low contribution of biomass burning. Estimated SOC-concentrations for all stations were between 11% and 33% of total OC. SOC-concentrations obtained with PMF exceeded EC-tracer results more than 100% at the park in the period with low biomass burning emissions in PM10. The deviations were besides others attributed to the high ratio of biogenic to combustion emissions and to direct exposure to vegetation. The occurrences of biomass burning emissions in contrast lead to increased SOC-concentrations compared to PMF in PM10. The obtained results distinguish that the EC-tracer-method provides well comparable results with PMF if sites are strongly influenced by one characteristic primary combustion source, but was found to be adversely influenced by direct and relatively high biogenic emissions. © 2014 by the authors.

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