TY - CONF A1 - Oberbeckmann, Sonja T1 - The Microplastic Microbiome N2 - Microplastics represent man-made and newly emerging surfaces in our ecosystems, where they interact with microorganisms. The ecosystem in focus of this presentation will be the aquatic environment. It will be portrayed, which microorganisms use microplastics as a habitat, how environmental factors shape this colonization, and why the biodegradation of plastics in the ocean is an overall unlikely process. We will also discuss whether potentially pathogenic microorganisms use microplastics as a raft. Finally, possible adaptation mechanisms of plastic-colonizing microorganisms will be presented, such as the production of photoreactive molecules. The microplastic microbiome has a large potential to harbor so far unknown species with curious traits, representing an exciting research topic for the future. T2 - Geomicrobiological and Geochemical Colloquium, GFZ CY - Potsdam, Germany DA - 20.02.2024 KW - Microplastics KW - Microbiome KW - Biofilm PY - 2024 AN - OPUS4-60203 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nordholt, Niclas A1 - Schreiber, Frank A1 - Kanaris, Orestis T1 - Consequences of BAC tolerance for selection and evolution in the presence of antibiotics N2 - The exposure to antimicrobial substances drives the evolution of antimicrobial resistance. Biocides are antimicrobials used as disinfectants, antiseptics and preservatives. They find application on a large scale in the industrial and medical sector, but also in private households. In terms of mass, the worldwide use of biocides exceeds that of antibiotics. Thus, despite their important role in preventing the spread of pathogens, due to their ubiquity, biocides are suspected to be drivers of the antimicrobial resistance crisis. In our work at BAM we try to understand how biocides contribute to the emergence of AMR, what the underlying adaptation principles and mechanisms are and how they compare to those found for antibiotics. Within our group, I mainly focus on the following two questions: How does phenotypic heterogeneity in bacteria affect the ability to survive treatment with biocides? And what are the consequences of phenotypic heterogeneity for the evolution of resistance to biocides and antibiotics? I will share published and unpublished results which demonstrate that phenotypic heterogeneity can enable the survival of biocide treatment and, through this, facilitate the evolution of AMR. On the other hand, we find that adaptation to a biocide can unexpectedly impair the ability to evolve resistance against an antibiotic. T2 - FEMS summer school for postdocs 2022: Microbial Evolvability Mechanisms: Resistance, Biology, and Strategies to Defeat and Detect CY - Split, Croatia DA - 27.04.2022 KW - Disinfection KW - Biocides KW - Evolution KW - Resistance KW - Biocide tolerance PY - 2022 AN - OPUS4-54846 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nordholt, Niclas T1 - The disinfectant glutaraldehyde induces antibiotic tolerance underpinned by phenotypic heterogeneity and transcriptome remodeling N2 - Glutaraldehyde is widely used as a disinfectant and preservative, but little is known about its effects on bacterial susceptibility to antibiotics and the selection of tolerant phenotypes. We found that short-term exposure to sub-inhibitory levels of glutaraldehyde makes E. coli resistant to high doses of bactericidal antibiotics from different classes. This tolerance is associated with delayed, heterogeneous regrowth dynamics and global transcriptome remodeling. We identified over 1200 differentially expressed genes, including those related to antibiotic efflux, metabolic processes, and the cell envelope. The cells entered a disrupted state likely due to the unspecific mode-of-action of glutaraldehyde. Despite this unregulated response, we identified several differentially expressed genes not previously associated with antibiotic tolerance or persistence that induce antibiotic tolerance when overexpressed alone. These findings highlight how the unspecific mode-of-action of disinfectants can make bacteria temporarily resistant to antibiotics. They have implications for settings where disinfectants and antibiotics are used in close proximity, such as hospitals and animal husbandry, and for the selection dynamics of tolerant pheno- and genotypes in fluctuating environments where microorganisms are exposed to these substances, such as sewage systems. A trade-off arises from overcoming the disrupted state as quickly as possible and maintaining antibiotic tolerance. T2 - µClub Seminar Series CY - Berlin, Germany DA - 26.05.2023 KW - Glutaraldehyde KW - Biocides KW - Tolerance KW - Bacteria KW - Disinfection KW - Heterogeneity PY - 2023 AN - OPUS4-58031 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bresch, Harald A1 - Braun, Ulrike A1 - Hodoroaba, Vasile-Dan A1 - Jann, Oliver A1 - Seeger, Stefan A1 - Unger, Wolfgang A1 - Resch-Genger, Ute T1 - Forschungsprojekte an der BAM N2 - Übersicht über die laufenden Projekte der BAM mit Bezug zur Nano-Thematik. Der Fokus liegt auf der Entwicklung der OECD-Prüfrichtlinie zur Partikelgrößenverteilung und auf den Projekten, die einen Anknüpfungspunkt für die anderen Bundesoberbehörden bilden könnten. T2 - Behördenklausur zur Nanosicherheit 2019 CY - Berlin, Germany DA - 26.06.2019 KW - Bundesoberbehörden KW - Nano KW - Behördenklausurtagung PY - 2019 AN - OPUS4-49575 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seeger, Stefan T1 - Regulatory Trends in the EU for Chemicals and Nanomaterials N2 - The presentation gives an overview on existing and upcoming REACH regulations in the EU concerning nanomaterials. T2 - BAM - JBMIA (Japan Business Machine and Information System Industries Association) Meeting, JBMIA Emissions Working Group Meeting CY - Tokyo, Japan DA - 04.05.2019 KW - Nanomaterials KW - REACH KW - EU regulations PY - 2019 AN - OPUS4-47814 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seeger, Stefan T1 - Analysis of air pollutants in ambient and indoor aerosolsby TXRF - application examples N2 - Quantitative chemical analysis of airborne particulate matter (PM) is vital for the understanding of health effects in indoor and outdoor environments, as well as for enforcing air quality regulations. Typically, airborne particles are sampled over long time periods on filters, followed by lab-based analysis, e.g., with inductively coupled plasma mass spectrometry (ICP-MS). Within the EURAMET EMPIR AEROMET project, cascade impactor aerosol sampling was combined for the first time with on-site total reflection X-ray fluorescence (TXRF) spectroscopy to develop a tool for quantifying particle element compositions within short time intervals and even on-site. This makes variations of aerosol chemistry observable with time resolution of only a few hours and with good size resolution in the PM10 range. A proof of principles of this methodological approach and the comparison to standard methods within the scope of a field campaign will be presented. Secondly, aerosol sampling and TXRF analysis seems suitable for the quantification of elements in indoor aerosols as well and may provide an important enhancement of existing methods for the analysis of organic species in aerosols (such as sampling and TD-GC/MS). As an example, the TXRF analysis of particles emitted from laser printers under controlled conditions in an environmental test chamber will be presented. T2 - TXRF Journal ClubB CY - Online meeeting DA - 24.02.2022 KW - Aerosol KW - TXRF KW - Cascade impactor KW - ICP-MS KW - Particles KW - Air quality monitoring KW - Element mass concentration PY - 2022 AN - OPUS4-54418 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seeger, Stefan A1 - Osan, J. A1 - Czömpöly, O. A1 - Gross, A. A1 - Stoßnach, H. A1 - Stabile, L. A1 - Ochsenkuehn-Petropoulou, M. A1 - Tsakanika, L. A. A1 - Lymperopoulou, T. A1 - Goddart, S. A1 - Fiebig, M. A1 - Gaie-Levrel, F. A1 - Rissler, J. A1 - Kayser, Y. A1 - Beckhoff, B. T1 - Element mass concentrations in ambient aerosols, a comparison of results from filter sampling & ICP-MS ans cascade impactor sampling & mobile total reflection X-RAY fluorescence spectroscopy N2 - Quantitative chemical analysis of airborne particulate matter (PM) is vital for the understanding of health effects in indoor and outdoor environments and required by EU air quality regulations. Typically, airborne particles are sampled on filters, followed by lab-based analysis, e.g., with inductively coupled plasma mass spectrometry (ICP-MS). Within the EURAMET EMPIR AEROMET project, cascade impactor aerosol sampling was combined with on-site total reflection X-ray fluorescence (TXRF) spectroscopy. The study aimed at a proof of principles for this new mobile and on-size tool for the quantification of aerosol element compositions and element mass concentrations within short time intervals of less than 12 h. In a field campaign the method’s technical feasibility could be demonstrated. The TXRF results were traced back to a stationary, reference-free XRS setup in the laboratory of the German national metrology institute PTB at the BESSY II electron storage ring in Berlin, Germany. Simultaneous PM10-filter sampling, followed by standardized lab-based analysis, allowed for a comparison of the field campaign data of both methods. As Fig. 1 shows, the correspondence between PM10 filter sampling and ICP-MS, and on the other hand, cascade impactor sampling and TXRF is quite encouraging. However, for some of the analysed elements, e.g. V and Pb, the observed deviations are higher than expected and this highlights the fact, that spectral deconvolution strategies for TXRF on cascade impactor samples still need some improvement. This work was supported by the EMPIR programme, co-financed by the Participating States and from the European Union’s Horizon 2020 research and innovation programme, through grant agreements 16ENV07 AEROMET and 19ENV08 AEROMET II T2 - 12th International Conference on Instrumental Methods of Analysis (IMA-2021) CY - Athens, Greece DA - 20.09.2021 KW - Aerosol KW - TXRF KW - Reference method KW - Cascade impactor KW - Ambient aerosols KW - Air quality monitoring KW - Element mass concentration KW - Size resolved chemical composition KW - Time resolved chemical composition KW - ICP-MS PY - 2021 AN - OPUS4-53597 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, Selina A1 - Kanaris, Orestis A1 - Nordholt, Niclas A1 - Schreiber, Frank T1 - Effect of biocides on the evolution and spread of resistance N2 - Biocides used as material preservatives are in contact with various environments during direct application or passive leaching from protected materials [1]. Antimicrobial resistance (AMR) is a global health problem and the environment is an important compartment for the evolution and transmission of AMR [2,3]. Soil is an environment with a large reservoir of natural microbial communities and antimicrobial resistance (AMR) genes. Those natural microbial communities are frequently exposed to biocides used as material preservatives. Previous studies have shown that antibiotics, metals and pesticides affect the underlying processes of resistance evolution and spread; namely de novo mutagenesis and horizontal gene transfer by conjugation and transformation in microbial communities. However, it is unknown if active substances used in material preservatives are involved in these processes. We show that biocides used as material preservatives affect rates of mutation and conjugation in microorganism in a species- and substance-dependent manner, while rates of transformation are not directly affected. Our data highlights the importance of assessing the contribution of material preservatives on AMR evolution and spread in the environment. T2 - RokoCon2022 CY - Berlin, Germany DA - 29.09.2022 KW - Biocide KW - Antimicrobial resistance KW - Tolerance KW - Horizontal gene transfer KW - Mutation rate PY - 2022 AN - OPUS4-56431 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bresch, Harald A1 - Rühle, Bastian A1 - Hodoroaba, Vasile-Dan A1 - Seeger, Stefan A1 - Resch-Genger, Ute A1 - Braun, Ulrike A1 - Jann, Oliver A1 - Wilke, Olaf A1 - Geißler, Daniel A1 - Schmidt, Alexandra A1 - Unger, Wolfgang A1 - Sturm, Heinz T1 - Stand der Aktivitäten zur gemeinsamen Forschungsstrategie N2 - Die gemeinsame Forschungsstrategie der Bundesoberbehörden zur Nanotechnologie wurde 2016 veröffentlicht. Die darin enthaltenen Aufgaben wurden von den Bundesoberbehörden vielfältig bearbeitet. Diese Präsentation gibt einen Überblick über die Projekte, die von der BAM bis 2019 bearbeitet wurden/werden und sich in den Rahmen der Forschungsstrategie einordnen. T2 - Workshop zur gemeinsamen Forschungsstrategie der Bundesoberbehörden „Nanomaterialien und andere innovative Werkstoffe: anwendungssicher und umweltverträglich“ CY - Berlin, Germany DA - 02.09.2019 KW - Nano KW - Bundesoberbehörden KW - Forschungsstrategie KW - Nanomaterialien KW - Nanotechnologie PY - 2019 AN - OPUS4-49586 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bresch, Harald A1 - Hodoroaba, Vasile-Dan A1 - Radnik, Jörg T1 - Übersicht zu Projekten bei DIN/ISO, VAMAS und CCQM N2 - Information der AG-Nano der Bundesoberbehörden zur Strukturierung und den laufenden Aktivitäten bei ISO und DIN sowie VAMAS und CCQM. T2 - Behördenklausur Nano der Bundesoberbehörden CY - Berlin, Germany DA - 14.09.2022 KW - Nano KW - Bundesoberbehörden KW - Behördenklausurtagung PY - 2022 AN - OPUS4-56757 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -