87 research outputs found
Consumer exposure to biocides - identification of relevant sources and evaluation of possible health effects
<p>Abstract</p> <p>Background</p> <p>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.</p> <p>Methods</p> <p>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.</p> <p>Results</p> <p>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.</p> <p>Conclusions</p> <p>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.</p
Ecological networks: Pursuing the shortest path, however narrow and crooked
International audienceRepresenting data as networks cuts across all sub-disciplines in ecology and evolutionary biology. Besides providing a compact representation of the interconnections between agents, network analysis allows the identification of especially important nodes, according to various metrics that often rely on the calculation of the shortest paths connecting any two nodes. While the interpretation of a shortest paths is straightforward in binary, unweighted networks, whenever weights are reported, the calculation could yield unexpected results. We analyzed 129 studies of ecological networks published in the last decade that use shortest paths, and discovered a methodological inaccuracy related to the edge weights used to calculate shortest paths (and related centrality measures), particularly in interaction networks. Specifically, 49% of the studies do not report sufficient information on the calculation to allow their replication, and 61% of the studies on weighted networks may contain errors in how shortest paths are calculated. Using toy models and empirical ecological data, we show how to transform the data prior to calculation and illustrate the pitfalls that need to be avoided. We conclude by proposing a five-point checklist to foster best-practices in the calculation and reporting of centrality measures in ecology and evolution studies. The last two decades have witnessed an exponential increase in the use of graph analysis in ecological and conservation studies (see refs. 1,2 for recent introductions to network theory in ecology and evolution). Networks (graphs) represent agents as nodes linked by edges representing pairwise relationships. For instance, a food web can be represented as a network of species (nodes) and their feeding relationships (edges) 3. Similarly, the spatial dynamics of a metapopulation can be analyzed by connecting the patches of suitable habitat (nodes) with edges measuring dispersal between patches 4. Data might either simply report the presence/absence of an edge (binary, unweighted networks), or provide a strength for each edge (weighted networks). In turn, these weights can represent a variety of ecologically-relevant quantities, depending on the system being described. For instance, edge weights can quantify interaction frequency (e.g., visitation networks 5), interaction strength (e.g., per-capita effect of one species on the growth rate of another 3), carbon-flow between trophic levels 6 , genetic similarity 7 , niche overlap (e.g., number of shared resources between two species 8), affinity 9 , dispersal probabilities (e.g., the rate at which individuals of a population move between patches 10), cost of dispersal between patches (e.g., resistance 11), etc. Despite such large variety of ecological network representations, a common task is the identification of nodes of high importance, such as keystone species in a food web, patches acting as stepping stones in a dispersal network , or genes with pleiotropic effects. The identification of important nodes is typically accomplished through centrality measures 5,12. Many centrality measures has been proposed, each probing complementary aspects of node-to-node relationships 13. For instance, Closeness centrality 14,15 highlights nodes that are "near" to all othe
Untersuchung der Reaktionen e+e- -> p+p- und e+e- -> p-oomega mit dem TASSO Detektor
SIGLETIB Hannover: RA 5527(87/01) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman
Real-life treatment practice for malignant pleural mesothelioma in Belgium
OBJECTIVES: Malignant pleural mesothelioma (MPM) is a rare and aggressive cancer, for which treatment is often limited to palliative combination chemotherapy. Multimodality-therapy, including radical surgery, is largely restricted to clinical trials, leaving its benefit currently unclear. This study aimed to get a comprehensive view on real-world MPM treatment at the Belgian population level, to assess survival and to identify prognostic factors. MATERIALS AND METHODS: The study period covered the incidence years 2004-2012 (N = 1453). Starting from the Belgian Cancer Registry, additional information regarding patient characteristics, diagnosis and treatment was retrieved from multiple data sources. Adjusted cox proportional-hazard regression models using time-dependent covariates were performed to assess survival in relation to treatment patterns and centre volume. RESULTS: Sixty-nine percent of patients underwent tumour-directed treatment, mostly cisplatin-pemetrexed chemotherapy. Radical surgery was mainly performed in younger patients with epithelioid subtype. Centre volume, surgery and chemotherapy showed a positive relation with survival in univariable analyses, but only chemotherapy remained significantly relevant in multivariable analyses. Younger patients, females, and epithelioid subtypes also independently had a better survival. CONCLUSION: This large population-based study provides insights in MPM treatment practice in Belgium. Centre volume and surgery being related to survival in univariable analyses, only chemotherapy remained prognostic after adjustment.status: publishe
Real-life treatment practice for malignant pleural mesothelioma in Belgium
OBJECTIVES: Malignant pleural mesothelioma (MPM) is a rare and aggressive cancer, for which treatment is often limited to palliative combination chemotherapy. Multimodality-therapy, including radical surgery, is largely restricted to clinical trials, leaving its benefit currently unclear. This study aimed to get a comprehensive view on real-world MPM treatment at the Belgian population level, to assess survival and to identify prognostic factors. MATERIALS AND METHODS: The study period covered the incidence years 2004-2012 (N = 1453). Starting from the Belgian Cancer Registry, additional information regarding patient characteristics, diagnosis and treatment was retrieved from multiple data sources. Adjusted cox proportional-hazard regression models using time-dependent covariates were performed to assess survival in relation to treatment patterns and centre volume. RESULTS: Sixty-nine percent of patients underwent tumour-directed treatment, mostly cisplatin-pemetrexed chemotherapy. Radical surgery was mainly performed in younger patients with epithelioid subtype. Centre volume, surgery and chemotherapy showed a positive relation with survival in univariable analyses, but only chemotherapy remained significantly relevant in multivariable analyses. Younger patients, females, and epithelioid subtypes also independently had a better survival. CONCLUSION: This large population-based study provides insights in MPM treatment practice in Belgium. Centre volume and surgery being related to survival in univariable analyses, only chemotherapy remained prognostic after adjustment.status: publishe
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