Sanitär- und Kommunaltechnik; Umwelttechnik
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Im Verbundprojekt R-Rhenania wird eine industrielle Demonstrationsanlage am Standort der Monoverbrennungsanlage Altenstadt der Firma Emter errichtet und im Jahr 2024 den Betrieb aufnehmen. Die vorhandene Rostfeuerung-Monoverbrennung wird so umgebaut, dass ein neues thermochemisches Verfahren integriert werden kann, welches hochwirksame und schadstoffarme Dünger produziert (bis zu 17.000 t/a). Die thermochemischen Produkte werden in Gefäß- und Feldversuchen im ökologischen Landbau auf ihre Düngewirkung getestet. Die Umweltverträglichkeit der Demonstrationsanlage wird untersucht, wie auch die Übertragbarkeit des Verfahrens auf weitere Regionen.
High polarity analyte(s) in aqueous media: determination of L-PFOA and L-PFOS in ground water
(2022)
The CCQM-K156 comparison was coordinated by TUBITAK UME on behalf of the Organic Analysis Working Group (OAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) for National Measurement Institutes (NMIs) and Designated Institutes (DIs) which provide measurement services in organic analysis under the 'Comité International des Poids et Mesures' Mutual Recognition Arrangement (CIPM MRA).
Perfluoro alkyl substances (PFAS) such as PFOS and PFOA have been used in numerous industrial applications and products. Because of their high stability and resistance to biodegradation, atmospheric photooxidation, direct photolysis and hydrolysis, they are extremely persistent in the environment. The European Union (EU) Water Framework Directive lists PFOS as a priority hazardous substance that poses a significant risk to the aquatic environment. The use of PFOS-containing Aqueous Film-Forming Foams (AFFFs) has been banned since June 2011 in the EU. As relatively water-soluble, effectively non-degradable compounds, PFOS and PFOA migrate to ground water. They are not removed in the conventional drinking water treatment, and therefore cause health risks in polluted areas. The EU Drinking Water Directive and the European Commission has proposed a limit value of 100 ng/L for the sum of 20 PFAS, including PFOS and PFOA.
This study provides the means for assessing measurement capabilities for determination of high polarity measurands in a procedure that requires extraction, clean-up, analytical separation and detection. Successful participation in CCQM-K156 demonstrates measurement capabilities in determining mass fraction of organic compounds, with a molecular mass of 200 g/mol to 700 g/mol, having high polarity pKow -2, in a mass fraction range from 0.5 ng/kg to 500 ng/kg in aqueous media.
Nine NMIs and DIs participated in the CCQM-K156 key comparison. Seven institutes reported their results. SPE was applied in the sample pre-treatment and LC-MS was applied for detection. All participating laboratories applied isotope dilution mass spectrometry (IDMS) techniques for quantification. Participants established the metrological traceability of their results using certified reference materials (CRMs) from NMIs with stated traceability; where commercially available high purity materials were used the purity was determined in-house. The CCQM-K156 results for L-PFOA and L-PFOS range from 2.75 ng/kg to 5.50 ng/kg with a % RSD of 19.5 % for L-PFOA and from 2.04 ng/kg to 4.45 ng/kg with a % RSD of 21.3 % for L-PFOS. The KCRV was assigned using a Hierarchical Bayesian Random Effects Model (HB REM) estimator from the values reported by six of the participants. One participant result of L-PFOS and one result of L-PFOA were excluded from the KCRV for technical reasons. The KCRV was 4.9 ng/kg ± 0.4 ng/kg for L-PFOA and 3.8 ng/kg ± 0.4 ng/kg for L-PFOS. The six institutes that were included in the assignment of consensus KCRV all agreed within their standard uncertainties.
To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.
The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Im Verbundprojekt RUSEKU wurde die Probenahme von Wasserproben entscheidend weiterentwickelt. Wichtig ist hierbei zu gewährleisten, dass genügend Merkmalsträger in jeder Probe untersucht werden. Es muss daher eine für den Probenahmeort repräsentative Beprobung hinsichtlich des Wasservolumens in Abhängigkeit der Partikelanzahl gewährleistet sein.
Das Hauptaugenmerk lag im vorliegenden Projekt auf einer praxisnahen Beprobungsstrategie. Es wurden verschiedene Konzepte ausprobiert.
• Grundsätzlich hat sich gezeigt, dass eine Stichprobe eine Momentaufnahme des MP-Massengehaltes zeigt. Es wird eine hohe Statistik, also eine Vielzahl an Messungen am gleichen Probenahmeort, benötigt, um eine valide Aussage über den MP-Gehalt zu machen.
• Es zeigt sich, dass eine integrale Probenahme über mehrere Wochen mit dem SK routinemäßig möglich ist. Die erfassten MP-Massen sind reproduzierbar und robust.
• Die DFZ ist für Stichproben geeignet. Partikel < 50 µm werden eventuell unterschätzt
• Die fraktionierte Filtration kann für Stich- und Mischproben direkt im Feld genutzt werden. Fraktionen von 10 und 5 µm werden später im Labor Vakuum filtriert. Es erfolgt eine Fraktionierung der Probe mit Siebmaschenweiten von 1000, 500, 100, 50, 10 und 5 µm.
• Die fraktionierte Filtration kann auch anschließend an die Beprobung mit dem SK zur Anwendung kommen. Wird die mit dem SK gewonnene Wasserprobe fraktioniert filtriert, kann neben einem MP-Gesamtgehalt auch eine Einschätzung über die Partikelgrößen gewonnen werden.
• Für Wässer mit geringen Partikelzahlen wurde ein Messfiltertiegel entwickelt. Dieser hat eine Maschenweite von 6 µm. Seine Anwendung kann mögliche Verluste beim Transferieren vom Probenahmetool zum Messgefäß und mögliche Kontaminationen reduzieren.
Die Optimierung der Probenahmestrategie wurde durch Modellversuche und Simulationen unterstützt. Modellversuche zum Sinkverhalten und Simulationen von MP in realen Gewässern verdeutlichten das komplexe Verhalten der Partikel. Es konnte gezeigt werden, dass Partikel ab einer bestimmten Größe (und kleiner) bei genügend starker Turbulenz sich in der Wassersäule unabhängig von ihrer Dichte verhalten und so auch MP mit kleiner Dichte (z.B. PE) in der gesamten Wassersäule zu finden sind. Es konnte mit dem TEM die Existenz von NP gezeigt werden.
Ein wesentlicher Aspekt des RUSEKU Projektes war die Beprobung realer Kompartimente. Beprobt wurde neben Oberflächengewässern, das urbane Abwassersystem der Stadt Kaiserslautern, Waschmaschinenabwasser und Flaschenwasser.
• In Oberflächengewässern wurde hauptsächlich PE gefunden. Je nach Probe und Gewässer konnten auch PP, PS, PET, PA, SBR und Acrylate nachgewiesen werden.
• Im urbanen Abwassersystem der Stadt Kaiserslautern konnte an allen Probenahmestandorten MP nachgewiesen werden. Es wurde hauptsächlich PE, neben geringeren Mengen an PP, PS und SBR gefunden. Nach einem Regenereignis war der SBR Anteil deutlich erhöht.
• Die Beprobung eines realen Wäschepostens, bestehend aus T-Shirts und Hemden mit PA/CO oder PES/CO Mischgewebe, zeigte einen PA- und PES-Austrag im Waschwasser. Der überwiegende Teil der detektierten Fasern ist aber auf Baumwolle zurückzuführen. Reine gravimetrische Messungen zur Detektion von MP führen zu einer starken Überschätzung.
• In Flaschenwasser (PET-Flaschen) konnte MP detektiert werden. PET wurde nur im stillen Mineralwasser, nicht in Mineralwasser mit Kohlensäure gefunden werden. Teilweise wurde auch das MP-Material des Verschlusses im Wasser detektiert.
• Für Luftproben konnte ein Aufbau zur größenselektiven Beprobung getestet werden.
Neben der Probenahme hat das Projekt auch gezeigt, dass die TED-GC/MS geeignet für die MP-Detektion im Routinebetrieb ist. Die TED-GC/MS konnte weiter optimiert werden. Es wurden MP-Massen bestimmt.
Im Projekt wurden erste realitätsnahe Referenzmaterialien für die MP Detektion hergestellt. Die Herstellung von realitätsnahen Polymeren in ausreichender Homogenität und Menge hat sich als große Herausforderung herausgestellt.
Bisphenol A (BPA) is used in Polycarbonate, Polyacrylic resins, Polysulfones, Epoxy resins, and Polyetherimides. It is also used in recycled Polyvinyl chloride [1–3]. BPA has been classified as a substance of very high concern (SVHC) under REACH [4] due to its endocrine disrupting properties. The German competent authorities want to reduce the content of BPA in the environment. Possible substitutes for BPA are Bisphenol B (BPB), Bisphenol E (BPE),
Bisphenol F (BPF), or Bisphenol S (BPS), as they are similar in structure.
BPA-based materials have a wide area of application especially outside. These outdoor applications are exposed to different external influences, including physical, biological, mechanical and chemical influences. This results in damage and aging of the material with leaching or migration into the environment. There, the substance is transformed by various transformation processes. The emerging metabolites and transformation products (TPs) can have different properties than the parent substance. Understanding the fate and behavior of the emerging pollutants is very important.
Therefore, different transformation products of selected bisphenols will be generated and analyzed:
To investigate the fate of different bisphenols in water treatment plants technical transformation products [5] will be generated by chlorination, ozonization, the Fenton reaction, and UV-radiation.
For the investigation of the fate of Bisphenols in surface water global radiation will be simulated with UVA-lamps
Simulation of phase-I-metabolism with an electrochemical cell coupled to mass spectrometry (EC-MS).
Der Koalitionsvertrag der Bundesregierung betont in seiner Präambel zur Zukunft Deutschlands in Bezug auf die notwendige Modernisierung, dass „dieser Fortschritt auch mit einem Sicherheitsversprechen einhergehen muss“. Die Bundesanstalt für Materialforschung und -prüfung (BAM) stellt mit ihrem Auftrag „Sicherheit in Technik und Chemie“ und ihrer über 150-jährigen Kompetenz sicher, dass ein nachhaltiger technischer Fortschritt von einem Sicherheitsversprechen für die Bürger*innen begleitet ist.
Durch ihre Interdisziplinarität, die thematische Breite, die langjährige Erfahrung und die unabhängige Rolle als Ressortforschungseinrichtung ist die BAM in einer herausragenden Lage, als zentraler Akteur die Entwicklung unterschiedlichster Technologien unter Berücksichtigung sicherheitstechnischer Aspekte voranzubringen, das Vertrauen der Gesellschaft in diese Technologien sicherzustellen und dadurch die Basis für erfolgreiche Innovationen zu schaffen.
Der Fokus ihrer Arbeit liegt auf den fünf Themenfeldern Energie, Infrastruktur, Umwelt, Material und Analytical Sciences. Wichtige Themen betreffen dabei sowohl die Energiewende (Wasserstoff, elektrische Energiespeicher, Windenergie) als auch Bereiche der Technologiesouveränität wie die additive Fertigung, zuverlässige Materialdaten, Zustandsüberwachung und Kreislaufwirtschaft.
Die Digitalisierung und den digitalen Wandel unterstützt die BAM in Bezug auf technologieübergreifende Rahmenbedingungen besonders in der Initiative Qualitätsinfrastruktur-Digital (QI-Digital), in der gemeinsam mit weiteren zentralen Akteuren der deutschen QI Lösungen für die Qualitätssicherung in einer digitalisierten Welt entwickelt werden.
Grundvoraussetzung für sichere Technologien und Innovationen ist eine leistungsfähige Forschung und Entwicklung ebenso wie Wissens- und Technologietransfer zur Umsetzung von Forschungsergebnissen in marktfähige Produkte und Dienstleistungen. Dafür bildet die Arbeit der BAM eine wichtige Basis.
Ihre Forschung ist mit der Wahrnehmung öffentlicher Aufgaben verbunden. Das Forschungsprogramm zeigt Perspektiven im Bereich ihres Aufgabenfeldes sowie ihrer damit verbundenen Forschungsaktivitäten transparent und politisch nutzbar auf und dient darüber hinaus der Koordinierung der Ressortforschung.
Das Forschungsprogramm der BAM wird alle zwei Jahre aktualisiert. Es gibt einen Überblick über die aktuellen und zukünftigen Forschungsthemen und die hierfür erforderlichen Rahmenbedingungen.
1. Projektreffen mit dem Umweltbundesamt für das Projekt MARKERIA (VH1802).
Ziel des Projektes ist es, die Eignung der Bestimmung eines oder mehrerer der genannten anthropogenen Marker im Abwasser zur Volumenkorrektur („Kalibration“) im SARS-CoV-2-Monitoring von Abwässern auf der Basis eines von der BAM zu erhebenden Messdatensatzes zu evaluieren.
ESI-CorA ist ein nationales Verbundprojekt mit dem Ziel des Nachweises von SARS-CoV-2 im Abwasser.
Das UBA hat als Teilprojekt das Projekt MARKERIA (VH1802) an die BAM vergeben.
Ziel des Projektes ist es, die Eignung der Bestimmung eines oder mehrerer der genannten anthropogenen Marker im Abwasser zur Volumenkorrektur („Kalibration“) im SARS-CoV-2-Monitoring von Abwässern auf der Basis eines von der BAM zu erhebenden Messdatensatzes zu evaluieren.
Vortrag zum Kick-off des Projektes.
Ziel des Projektes ist es, die Eignung der Bestimmung eines oder mehrerer der genannten anthropogenen Marker im Abwasser zur Volumenkorrektur („Kalibration“) im SARS-CoV-2-Monitoring von Abwässern auf der Basis eines von der BAM zu erhebenden Messdatensatzes zu evaluieren.
2. Projekttreffen mit dem Umweltbundesamt zum Projekt MARKERIA (VH1802).
Ziel des Projektes ist es, die Eignung der Bestimmung eines oder mehrerer der genannten anthropogenen Marker im Abwasser zur Volumenkorrektur („Kalibration“) im SARS-CoV-2-Monitoring von Abwässern auf der Basis eines von der BAM zu erhebenden Messdatensatzes zu evaluieren.
Natural and synthetic estrogens are key endocrine-disrupting chemicals. Despite occurring at ultra-trace levels (below ng L-1), it is believed that they are contributing to an increase in feminized fish and other endocrine disruptive effects, and hence, their inclusion in the Watch list was not unexpected. One of the main sources ofestrogens to surface waters is wastewater effluent. Once in surface waters, they can partition into different compartments, i.e., water and suspended particulate matter. For this reason, there is an urgent need for a methodology to monitor estrogen levels below the environmental quality standards (EQS) set by the Water Framework Directive requirements.
In this study, a precise and accurate gas chromatography-mass spectrometry method (GC-MS/MS) for the analysis of estrone (E1), 17β-estradiol (17β-E2), 17α-estradiol (17α- E2), 17-alpha-ethinylestradiol (EE2), and estriol (E3) in whole water samples with ng L-1 limit of quantification (LOQ) was developed and validated in accordance with CEN/TS 16800:2020 guidelines.
Monitoring programs should generate high-quality data on the concentrations of substances and other pollutants in the aquatic environment to enable reliable risk assessment. Furthermore, the need for comparability over space and time is critical for analysis of trends and evaluation of restoration of natural environment. Additionally, research work and exercises at the European level have highlighted that reliable measurements of estrogenic substances at the PNEC level are still challenging to achieve.
The project EDC-WFD Metrology for monitoring endocrine disrupting compounds under the EU Water Framework Directive aims to develop traceable analytical methods for determining endocrine disrupting compounds and their effects, with a specific focus on three estrogens of the first watch list (17-beta-estradiol (17βE2), 17-alpha-ethinylestradiol (EE2), and estrone (E1)). Estrogens 17-alpha-estradiol (17E2) and estriol (E3) will be included to demonstrate the reliability of the developed methods and to support the requirements of Directive 2013/39/EC, Directive 2009/90/EC and Commission Implementation Decision (EU) 2018/840, hence improving the comparability and compatibility of measurement results within Europe. During the EDC-WFD project four selected effect-based methods (EBM) will be deeply investigated in order to improve their rationale use and their support in water quality assessment. In particular, the EBM sensitivity, specificity and accuracy on reference materials with single or mixture solutions of the five substances at a concentration of EQS values will be explored.
This contribution will present the objectives and methods applied within the EDC-WFD project.
Antibiotic resistance is a growing global problem which poses a massive threat to human health. Although human activity contributes to the acceleration of the process, bacteria have a self-driven stabilisation mechanism to protect themselves from such and other external threats: biofilm formation. Nonetheless, it is the adhesion of a single bacterial cell to a surface that triggers the formation of such network of biomolecules and microorganisms, as well as its hazardous consequences. The main objective of this work was to quantify the adhesion force of a single E. coli cell on a Ti substrate via the AFM-related single-cell force spectroscopy, with both the cell and the substrate material being of high clinical relevance. A set of 25 x 25 force displacement curves was acquired with a maximum force of 3.2 nN without dwell time, yielding a topography map and an adhesion force map that showed to be correlated. A mean adhesion force of 0.85 ± 0.175 nN was measured and the presence of cell appendages on the bacterial cell wall was verified through individual force-displacement curves. Bacterial viability was assessed after the measurements via live/dead staining.
Permanente und nachhaltige Deckung von Grundbedürfnissen der Nahrungs- und Materialversorgung, aber auch das Ausnutzen von Arbeitshilfen, der Gebrauch von Versuchstieren in der Wissenschaft und die Freude an tierischer Begleitung in der Freizeit waren Beweggründe für die Domestikation von Tieren. Haustiere gehen auf eine zu ihrer Art gehörige Stammform einer Wildtierart zurück. Haustier und Wildtier sind somit Angehörige einer biologischen Spezies. Bei der Domestikation von Tieren spielte zwischenartliche Introgression keine Rolle. Die Domestikation von Haustieren durch Separation von kleinen Gruppen von Wildtieren erfolgte nur wenige Male an wenigen Orten (primäre Domestikationszentren). Haustiere bilden artübergreifend auffällig ähnliche morphologische und ethologische Merkmale aus (Domestikationssyndrom). Domestikation bei Wirbeltieren erfolgt primär über Selektion auf zutrauliches und zahmes Verhalten und unterliegt einem sehr komplexen pleiotropen Netzwerk von Regelkreisen. Die Domestikation ist ein koevolutiver Prozess und das Resultat eines bilateralen wechselseitigen Zusammenfindens von Prädispositionen und reziproken Valenzen der jeweiligen Partner von Haustier und Mensch.
We investigated the selection dynamics between a benzalkonium chloride (BAC)-tolerant Escherichia coli strain (S4) and a sensitive wild type under four conditions: in the absence of antibiotics and in the presence of three different sub-inhibitory concentrations of the antibiotic ciprofloxacin in liquid cultures. The wild type was selected over the BAC-tolerant strain in the absence of antibiotics, while the opposite was observed at all ciprofloxacin concentrations investigated.Furthermore, we assessed the evolvability of resistance of the two strains to inhibitory concentrations of ciprofloxacin by performing a serial dilution evolution experiment with gradually increasing ciprofloxacin concentrations. The wild type had a higher probability to develop resistance to ciprofloxacin than the tolerant strain. By the end of the evolution experiment both strains evolved to grow at the highest ciprofloxacin concentration investigated, which was 2048 ×MIC of the wild type.
Assessing co-selection of biocide and antibiotic resistance in wastewater microbial communities
(2022)
Biocides are used for a wide range of purposes, including disinfectants or preservatives. Biocides play a major role in the prevention of microbial infections in healthcare and animal husbandry. The use of biocides often leads to the discharge of active biocidal substances into wastewater streams, causing the exposure of wastewater microbial communities to subinhibitory concentrations. In turn, it is known that wastewater treatment plants (WWTP) are hotspots for antibiotic resistant bacteria. Since similar mechanisms confer resistance to biocides and antibiotics, exposure to biocides can result in co-selection of antibiotic resistant bacteria in WWTP due to biocides. Here, we investigate the magnitude and the drivers of co-selection of antibiotic resistance in natural wastewater microbial communities upon biocide exposure. Microbial communities will be sampled at the WWTP Ruhleben in Berlin and characterized regarding their biocide and antibiotic resistance. Changes in the resistance level after exposure to different biocides will be determined by enumerating resistant and non-resistant E. coli and heterotrophic bacteria on selective plates with and without several biocides and antibiotics. Moreover, we are establishing a synthetic community comprising about 100 environmental E. coli isolates each with different antimicrobial resistance traits. Each isolate will be tagged with a unique DNA-barcode. All isolates will be pooled and exposed to different biocides at various concentrations. The barcode labeling enables us to determine the abundance of each isolate at the beginning and end of the experiment by transposon-tag sequencing. The project results will inform risk assessment of the effects of biocidal residues on antimicrobial resistance selection in WWTP.
The project is part of the BIOCIDE consortium funded within the call on Aquatic pollutants by JPI-AMR, JPI-OCEANS and JPI-WATER.
Analytical methods based on the selectivity of antibodies, often called immunoassays, are a back-bone of clinical laboratory diagnostics. To bring them to the field, i.e., to make immunoanalytical methods portable, hopefully even faster, more sensitive, and robust, advanced materials are re-quired. Materials can be novel labels, e.g., chemical or particle labels, such as fluorophores or na-noparticles. Carrier particles, such as magnetic or polymer beads, make it possible to adopt the as-says to meso- or microfluidic set-ups and encoding them opens the path to multiplex analysis. Spe-cialty electrodes can enable for higher sensitivity in electrochemical detection. Without research into better materials, efforts to bring analysis to the point-of-need will not bear fruit.
In urban waters, a multitude of organic micropollutants, often termed emerging pollutants, has been found over the last decades. Analytical methods suitable for trace analysis are needed that are desirably also fast, inexpensive and, if possible, robust and portable. Immunoanalytical, i.e., antibody-based, methods which are available in a broad range of formats, can be profitably used here to screen for the distribution and to monitor the trends of concentration levels of contaminants of emerging concern in the environment. Some of these formats are single-analyte but high-throughput methods. To use them wisely, indicator substances, sometimes called anthropogenic markers, should be selected and used in screening approaches, i.e., as indicators for contamination and the pre-selection of samples at which to have a closer look by multiplex methods like LC-MS/MS. Other methods are suitable to be performed on portable instrumentation in the field (on-site) or in facilities such as wastewater treatment plants for on-line monitoring of the treatment and elimination process. Furthermore, array technologies have been established that allow for parallel (multiplex) analysis of several analytes of interest.
The microtiter-plate based ELISA (Enzyme-linked Immunosorbent Assay) is the method of choice for the analysis of a large number of samples [1]. ELISAs are available to monitor for anthropogenic markers such as the antiepileptic carbamazepine, the analgesic diclofenac, the antihistaminic cetirizine, the steroid hormone estrone, the antimicrobial sulfamethoxazole, psychoactive caffeine and cocaine, the priority pollutant bisphenol A, and the bile acid isolithocholic acid. For on-site screening and monitoring, simpler formats, like mix-and-read assays, e.g., the Fluorescence Polarization Immunoassay (FPIA) [2] or Lateral-flow Immunoassays (LFIA) [3] are more suitable tools, the latter based on dipsticks or little cassettes, with which users have become very familiar during the COVID-19 pandemic via rapid antigen tests. The suitability of multi-analyte formats such as immunomicroarrays depends on the choice of a signal-producing system that provides small uncertainties and good reproducibility of the measurements. Bead-based (“suspension”) arrays, read out in flow cytometers, are a powerful platform for multiplex assays [4]. Electrochemical formats, run on portable devices, provide additional advantages as no light source is required. They are most promising for stand-alone analysers and biosensors [5].
The speed, low cost and on-site capabilities of these methods allow to gather a lot more data on anthropogenic compounds which enables to quantify inputs, differences in degradation power of elimination processes, dilution phenomena and a more precise image of individual water cycles which is demonstrated by several examples.
Immunoanalytical Techniques, i.e., antibody-based analytical methods, have been used for decades in clinical diagnostics. What makes them attractive for other fields of application is their short time-to-result and high sensitivity. Microplate-based assays such as ELISA have been adopted early in environmental and food analysis. Yet, to make immunoassays even faster, more sensitive, robust, and, most desirable, portable, advanced materials, sometimes developed for other purposes, can be profitably used to achieve these goals. Materials can be novel labels, e.g., chemical or particle labels, such as fluorophores or nanoparticles. Carrier particles, such as magnetic or polymer beads, make it possible to adopt the assays to meso- or microfluidic set-ups and encoding them opens the path to multiplex analysis. Specialty electrodes can enable for higher sensitivity in electrochemical detection. All this broadens the scope of application and lowers effort and cost for analysis at the point-of-need.
A vast number of emerging pollutants is being detected in the environment. Another lingering problem are health-threatening contaminants, such as mycotoxins, that deteriorate food and feed, and the pathogens themselves. Analytical methods, suitable for trace analysis, are needed that are desirably also fast, inexpensive and, if possible, robust and portable. It is set out, how immunoana-lytical, i.e., antibody-based methods, which are elaborated in a broad range of formats, can be profitably used to gain insights on the distribution and concentration trends of the target analytes at the point-of-need.
Rock-inhabiting black fungi are adapted to survive extreme stresses such as radiation and lack of water and are thus able to colonise arid material surfaces like solar panels and marble monuments. Black fungi can typically grow as one of two cell types: depending on the environmental conditions, they are able to form yeast-like cells or hyphal filaments. Knufia petricola is one member of the rock-inhabiting black fungi which functions as a model reference species. As there is no mathematical model for biofilm formation of RIF, we are going to develop a model for K. petricola which describes fungal growth on the level of individual cells adn biofilm formation.
In our current research project „Reincarnate“ we aim to anchor the idea of the circular economy in the European construction industry and significantly extend the life cycle of buildings, construction products and materials through innovative solutions. On the long term, this is an approach reduce construction waste by 80 percent and the CO2 footprint of the construction sector by 70 percent."
This project has received funding from the European Union’s Horizon Europe research and innovation programme and will take you on a tour on what are the drivers, what is the goal, who are the partners and how we want to make the world a better place!
Vorstellung der Themen der Nachwuchsgruppe "Materialcharakterisierung und -informatik für die Nachhaltigkeit im Bauwesen" von Prof. Sabine Kruschwitz (TU Berlin und BAM)
Generation of experimental uptake rates (UR) for > 70 VOCs (7d /100 μg m-3)
Application in German Environmental Survey – VOC exposure assessment
Assurance of transparency concerning UR generation and uncertainty creates basis for decision making and comparability of measurement results.
Exemplarily the uncertainty u(UR) of toluene UR was modelled and determined statistically with own laboratory data (relative standard deviation of actively sampled test gas atmosphere – RSDa and n = 5 exposed passive samplers – RSDp) in line with EN 838 as well as from variation of literature UR – RSD UR,lit.
Deciphering microbiological influenced corrosion processes on steel with single cell-ICP-ToF-MS
(2022)
Microbiologically influenced corrosion (MIC) is a highly unpredictable process dictated by the environment, microorganisms, and the respective electron source. Interaction pathways between cells and the metal surface remain unclear. The development of this novel single cell-inductively coupled plasma-time of flight-mass spectrometry analytical method and a MIC-specific staining procedure facilitate the investigation of steel-MIC interactions. With this it is possible to analyze the multi-elemental fingerprint of individual cells. The detection method revealed elemental selectivity for the corrosive methanogenic archaeal strain Methanobacterium-affiliated IM1. The interface between material and environmental analysis thus receives special attention, e.g., when considering MIC on solid steel. Hence, the possible uptake of individual elements from different steel samples is investigated. Results showed the cells responded at a single-cell level to the different types of supplemented elements and displayed the abilities to interact with chromium, vanadium, titanium, cobalt, and molybdenum from solid metal surfaces. The information obtained will be used in the future to elucidate underlying mechanisms and develop possible material protection concepts, thus combining modern methods of analytical sciences with materials research.
References.
Materials are key for our modern communities. In particular metals play important roles in all areas of our daily life - from building materials to high tech products.
Due to the increasing consumption of metals and corresponding waste production, an elevated release into the environment takes place. Furthermore, metals in direct contact with the environment undergo corrosion leading to a release into the (aquatic) environment. Thus, lifespan of products/buildings are substantially reduced – hence unnecessary economic costs arise. Thus, research in this regard is needed within the force field of metal/material - environment.
Evaluating the environmental impact of materials as well as developing “safe” materials, new analytical methods are highly needed. One promising powerful tool is single cell-ICP-ToF-MS for multi-elemental analysis on a single cell/organism level.
Within this presentation the concept, strength as well as challenge of single cell-ICP-MS are briefly introduced. Two application examples are presented: (i) assessing the environmental impact of metals and (ii) the impact of the environment on metal-based materials and the derivation of potential environmental-friendly material protection strategies. These applications highlight the strength of new analytical approaches to explore the durability and safety of newly developed materials. Thus, analytical chemistry is one corner stone to transformation of modern society into circular economy (CEco).
(i) Diatoms are located at the bottom of the food chain. Thus, toxicological relevant metals taken up by diatoms possibly accumulate within the food web causing harmful effects. Diatoms are common test system in ecotoxicology. To investigate potential metal uptake and effects, we developed an on-line single cell-ICP-ToF-MS approach for multi-elemental diatom analysis. Our approach is a new potential tool in ecotoxicological testing for metal-based materials.
(ii) Next to classical corrosion processes, microorganisms are responsible for so called microbially influenced corrosion (MIC). MIC is a highly unpredictable process relying on interaction pathways between cells and the metal surface. Sheding light on MIC processes and derivate potential protection strategies, we applied single cell-ICP-ToF-MS for MIC research on a single bacteria/archaea level. It turned out that microorganism are taking up particular metals from alloys - thus, single bacteria-ICP-ToF-MS will enable development of corrosion protection strategies.
•Overview of expertise of division Biophotonics
•Functional molecular and nanoscale luminescent reporters, probes, and
sensors including design principles available from division Biophotonics
•Examples for pH and O2 responsive molecular probes and particle sensors
•Surface group quantification Analytical methods and cleavable probes
•Concepts & standards for the validation and traceability of optical measurements
Question
Disinfectants and antimicrobial surfaces (AMCs) are important tools to prevent the spread of pathogens and antimicrobial resistant bacteria. However, concerns have been raised about the possibility for the evolution and selection of resistance against disinfectants and AMCs. In turn, resistance against disinfectants and AMCs can be associated to antibiotic resistance due to cross-resistance - a single mechanism conferring resistance to a disinfectant and an antibiotic- and co-resistance - two distinct mechanisms physically linked on e.g. a plasmid. The risk for resistance and cross-resistance during use of biocides (including disinfectants and AMCs) must be evaluated during authorization according to the EU biocidal product regulation. However, to date there is a lack of standardized methods that support risk assessment during the authorization process.
Methods
We used adaptive laboratory evolution (ALE) experiments which are based on repeated exposure of bacteria to disinfectants or AMCs. The experiments are followed by phenotypic (antimicrobial susceptibility testing) and genotypic (whole genome sequencing) characterization of the evolved strains. The basic idea of these experiments is to expose bacteria to lethal conditions and select for mutants with increased survival. This approach is fundamentally different to other ALE experiments, which commonly select for increased growth at subinhibitory concentrations. However, selection for increased survival represents a selective pressure that more realistically reflects selection under in-use conditions of disinfectants and AMCs.
Results
First, we studied adaptation of E. coli during repeated disinfection with benzalkonium chloride in a suspension assay. The experiments showed a 2000-fold increase in survival within 5 exposure cycles. The adaptive changes are linked to highly parallel mutations in genes related to lipid A biosynthesis, less negative cell surface charge, reduced growth rate and increased competitive ability in the presence of certain antibiotics. We use the same approach to develop standardizable ALE experiments based upon accepted standards that are used to determine the efficacy of disinfectants (EN 13697) and antimicrobial surfaces (ISO 22196). The results highlight pronounced adaptation of different test strains towards surface disinfection (benzalkonium chloride and isopropanol) and AMCs (copper).
Conclusion
Bacteria can adapt with increased survival towards lethal stress imposed by disinfectants and AMCs. The adaptive ability of bacteria to disinfectants and AMCs can be determined in a standardized manner.
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.
Biocides used as material preservatives are in contact with various environments during direct application or passive leaching from protected materials. Antimicrobial resistance (AMR) is a global health problem and the environment is an important compartment for the evolution and transmission of AMR. 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.
Simulating a Gas Source Localization Algorithm with Gas Dispersion Produced by Recorded Outdoor Wind
(2022)
This presentation reports the use of the first gas dispersion simulator capable of generating large wind fluctuation, to test a modification to a gas source localization algorithm and study how the change affects it. Gas source localization at an outdoor environment is a challenging task mainly due to the complexity of the spreading gas caused by the unpredictable nature of constantly changing wind. Therefore, a novel use of outdoor wind in developing a gas source localization system by simulation will be shared. To consider the characteristic of sudden but large and unpredictable changes in wind direction, recorded outdoor wind was used to simulate a realistic outdoor gas dispersion which has been done for the first time. With the use of this simulator, a modification to a mobile robot-based gas source localization algorithm was evaluated. Multiple simulations of the modified and the original algorithm were done to study the effect of the tested modification. The results showed that a small difference in the algorithm can greatly impact the results. From this study, we consider the use of simulation consisting of the necessary traits to evaluate outdoor gas source localization, has the potential to accelerate the development of a reliable localization system.
Der Vortrag fasst den aktuellen Stand der Forschung an der BAM zum Thema "Biorezeptive Betonfassaden" zusammen. Während im Projekt Funktionsbeton der Einfluss der Textur von ultrahochfestem Beton auf die Biorezeptivität im Vordergrund steht, wird im Projekt Algenbiofilmfassade untersucht, inwieweit ein Biofilm künstlich auf Betonsubstraten etabliert werden kann.
Microbiologically influenced corrosion (MIC) is a highly unpredictable process dictated by the environment, microorganisms, and the respective electron source. Interaction pathways between cells and the metal surface remain unclear. The development of this novel single cell-inductively coupled plasma-time of flight-mass spectrometry analytical method and a MIC-specific staining procedure facilitate the investigation of steel-MIC interactions. With this it is possible to analyze the multi-elemental fingerprint of individual cells. The detection method revealed elemental selectivity for the corrosive methanogenic archaeal strain Methanobacterium-affiliated IM1. The interface between material and environmental analysis thus receives special attention, e.g., when considering MIC on solid steel. Hence, the possible uptake of individual elements from different steel samples is investigated. Results showed the cells responded at a single-cell level to the different types of supplemented elements and displayed the abilities to interact with chromium, vanadium, titanium, cobalt, and molybdenum from solid metal surfaces. The information obtained will be used in the future to elucidate underlying mechanisms and develop possible material protection concepts, thus combining modern methods of analytical sciences with materials research.
Estrogens are endocrine disrupting chemicals and of high concerns due to demonstrated harmful effects on the environment and low effect levels. For monitoring and risk assessment, several estrogens were included in the "watch list" of the EU Water Framework Directive which sets very low environmental quality standard (EQS) levels for Estrone (E1) and 17β-Estradiol (E2) of 0.4 ng L−1 and for 17α-Ethinylestradiol (EE2) of 0.035 ng L−1 requiring sensitive detection methods, as well as extensive sample preparation. A sensitive, derivatization-free, isotope dilution calibration HPLC-MS/MS method for a panel of 5 selected estrogens (including the 3 estrogens of the EU WFD watchlist), and a procedure for the reproducible preparation of a representative whole water matrix including mineral water, humic acids and solid particulate matter are presented. These are used in a diligent comparison of classical solid phase extraction (SPE) on hydrophilic-lipophilic balanced (HLB) phase to SPE on an estrogen-specific molecularly imprinted polymer phase (MISPE) for ultra-trace levels of the analytes (1–10 ng L−1). Additionally, a two-step procedure combining HLB SPE disks followed by MISPE is evaluated. The tow-step procedure provides superior enrichment, matrix removal and sample throughput while maintaining comparable recovery rates to simple cartridge SPE. Estimated method quantification limits (MQLs) range from 0.109–0.184 ng L−1 and thus meet EQS-levels for E1 and E2, but not EE2. The representative whole water matrix provides a reproducible comparison of sample preparation methods and lays the foundation for a certified reference material for estrogen analysis. The presented method will serve as the basis for an extended validation study to assess its use for estrogen monitoring in the environment.
It is of high priority to capture the extent of microplastics (MP) contamination for understanding its impact and consequences to our environment. However, due to a lack of standardized methods, MP analysis as well as its quality assurance, is still a challenge. The thermal extraction desorption-gas chromatography/-mass spectrometry (TED-GC/MS) as a novel innovative thermoanalytic method can detect MP particles in environmental samples based on their decomposition products. According to MP analysis, a distinctively larger polyethylene (PE) content in comparison to other synthetic polymers was detected in environmental samples. Various substances within the matrix which have a similar molecular structure to PE, like fats and oils, might interfere with its marker and lead to an overestimation. In this investigation an automated extraction method, the accelerated solvent extraction (ASE), is introduced as quality control tool before TED-GC/MS measurement. Thereby, not the extract like usually used, but the solid filtrate is analyzed. The aim is to clean the environmental samples from solvent removable compounds which could lead to false positive signals and thus receive a more accurate PE mass. Consequently, a sample mimicking environmental samples with a defined matrix and a known polymer mass was generated. The common polymers polyethylene, polypropylene, polystyrene and styrene-butadiene rubber, used as an indication for tire wear, were added to the matrix. Different parameters for ASE extraction were varied such as different solvents, filters and purge time. Finally, a PE recovery rate of 91 % after extraction could be reached.
Glyphosate (GPS) is the most widely used pesticide in the world whose use increased dramatically after the introduction of genetically modified crops engineered to resist its herbicidal action during application. In recent years, there have been growing concerns over its toxicity following its classification by the International Agency for Research on Cancer (IARC) as a probable carcinogen as well as reports of its ecotoxicological effects. This resulted in increased efforts to develop quick and sensitive detection methods.
In this work, molecular imprinting was combined with direct fluorescence detection of GPS by improving its solubility in organic solvents using tetrabutylammonium (TBA+) and tetrahexylammonium (THA+) as counterions. To achieve fluorescence detection, a fluorescent crosslinker containing urea binding motifs was used as a probe for GPS-TBA and GPS-THA salts in chloroform, generating stable complexes through hydrogen bond formation. The GPS/fluorescent dye complexes were imprinted into 2–3 nm molecularly imprinted polymer (MIP) shells on the surface of sub-micron silica particles. Thus, the MIP binding behavior could be easily evaluated by fluorescence titrations in suspension to monitor the spectral changes upon addition of the GPS analytes. While MIPs prepared with GPS-TBA and GPS-THA both displayed satisfactory imprinting following titration with the corresponding analytes in chloroform, GPS-THA MIPs displayed better selectivity against competing molecules. Moreover, the THA+ counterion was found to be a more powerful phase transfer agent than TBA+, enabling the direct fluorescence detection and quantification of GPS in water in a biphasic assay. A limit of detection of 1.45 µM and a linear range of 5–55 µM, which matches well with WHO guidelines for the acceptable daily intake of GPS in water (5.32 µM), have been obtained. The assay can be further optimized to allow miniaturization into microfluidic devices and shows potential for on-field applications by untrained personnel.
The ubiquitous presence of unintended plastics in the environment has been an issue in scientific studies and public debate. Recent studies on MP findings are focused mainly on aquatic systems, while little is known about MP in terrestrial ecosystems. Fermentation residues, sewage sludge and compost are secondary raw material fertilizers and represent a possible input path of plastics in soils. Soils are final sinks for micro plastics. In this context, samples were taken in a combined fermentation and composting plant in Germany to get real compost samples which were investigated. Existing regulations include requirements for total contents of plastics in combination with visual determination methods. In order to avoid possible underdeterminations, precise detection methods should be used in the future from a scientific point of view. For this reason, the use of thermoanalytical detection is an appropriate way. Spectroscopic methods such as Raman or FTIR are not suitable for determining the mass content of microplastic, as these output a particle number. In Germany, compost is a potential vector for MP in soil due to its use as fertilizer. Therefore, we show the application of TThermoExtractionDesorption-GasChromatography-MassSpectrometry (TED-GC-MS) as a fast, integral analytical technique, which in contrast to the spectroscopic methods does not measure the number of particles but a mass content. In a nitrogen atmosphere the sample is pyrolyzed to 600 °C and an excerpt of the pyrolysis gases is collected on a solid phase adsorber. Afterwards, the decomposition gases are desorbed and measured in a GC-MS system. Characteristic pyrolysis products of each polymer can be used to identify the polymer type and determine the mass contents in the present sample. For the first time the work represents a routine procedure for the determination of plastics in composts and fermentation residues. This current study will also give inside in various important aspects of sample preparation, which include a meaningful size fractionation, a necessary density separation regarding the removal of inorganic contents and at finally a homogenization.
Per- und polyfluorierte Alkylsubstanzen (PFAS) im Klärschlamm - Analytische Methoden und Grenzwerte
(2022)
Per- und Polyfluoralkylsubstanzen (PFAS) sind eine Gruppe von mehr als 4700 anionischen und kationischen anthrophonen Stoffen, die aufgrund ihrer inerten chemischen Stabilität und ihrer Widerstandsfähigkeit gegen den Abbau durch Hitze oder Säuren in einer Vielzahl von Produkten verwendet werden. Infolge der ständigen Verwendung, vor allem in Feuerlöschschäumen für die Luftfahrt, wurden in Tausenden von Industrie- und Militäranlagen kontaminierte Böden und Grundwasservorkommen gefunden. Aufgrund der ständigen Verwendung von fluorierten Konsumgütern haben sich jedoch auch Abwässer und Klärschlamm aus Kläranlagen als Quelle für die Kontamination der aquatischen Umwelt mit PFAS erwiesen. Infolge der strengeren Vorschriften und Beschränkungen, die in den letzten Jahren für die Verwendung langkettiger (≥C8) PFAS erlassen wurden, findet in der chemischen Industrie eine deutliche Verlagerung hin zur Herstellung kurz- (C4-C7) und ultrakurzkettiger (C1-C3) Alternativen statt. Mit der Novellierung der Klärschlammverordnung im Jahr 2017 hat der deutsche Gesetzgeber die Ausbringung von Klärschlamm auf landwirtschaftlichen Flächen verboten, und bis 2029/2032 wird die Ausbringung von Klärschlamm in der Landwirtschaft vollständig verboten sein. Während die Belastung der Umwelt mit organischen Schadstoffen wie PFAS, Pestiziden und Arzneimitteln nicht mehr erwünscht ist, muss Phosphor (P) aus Klärschlamm weiterhin zur Herstellung hochwertiger P-Dünger für eine Kreislaufwirtschaft genutzt werden. Derzeit können pflanzenverfügbare P-Düngemittel aus Klärschlamm/Abwasser mit verschiedenen Behandlungsmethoden hergestellt werden, darunter Fällung, Auslaugung und thermische Behandlung. Der Verbleib von PFAS bei der Auslaugung, Ausfällung und Behandlung von Klärschlamm und Abwasser ist jedoch noch weitgehend unbekannt.
Detektion von Mikroplastik
(2022)
Per- and polyfluoroalkyl substances (PFAS) are a group of more than 4700 anionic and cationic anthrophonic substances which have been used extensively in a variety of products and industries due to their inert chemical stability and resistance to degradation by heat or acids. As a result of continuous use, mainly in aviation firefighting foams, thousands of industrial and military installations have been found to contain contaminated soil and groundwater resources. However, because of the continuous use of fluorinated consumer products, also effluents and sewage sludge from wastewater treatment plants (WWTPs) have been shown to be an important source of PFAS contamination into the aquatic environment. Resulting from recent stricter regulations and restrictions in the last years on the use of long chain (≥C8) PFAS, there is a significant shift in the chemical industry towards production of short (C4-C7) and ultrashort (C1-C3) chain alternatives. With the amendment of the Sewage Sludge Ordinance in 2017 the German legislation banned sewage sludge application on agricultural land, and by 2029/2032 sewage sludge will be completely prohibited from agricultural application. While environmental exposure of organic pollutants like PFAS, pesticides and pharmaceuticals are no longer desirable, phosphorus (P) from sewage sludge must still be used to produce high-quality P-fertilizers for a circular economy. Currently, plant-available P-fertilizers from sewage sludge/wastewater can be produced using a variety of treatment approaches including precipitation, leaching, and thermal treatment. However, the fate of legacy and emerging PFAS compounds during P leaching, precipitation and treatment from sewage sludge and wastewater is for the most parts still unknown.
Calcium sulfate minerals are abundant in natural and engineered environments and they exist in the form of three hydrates: gypsum (CaSO4·2H2O), bassanite (CaSO4·0.5H2O), and anhydrite (CaSO4). Due to their relevance in natural and industrial processes, the formation pathways of these calcium sulfate phases from aqueous solution have been the subject of intensive research1.
The state-of-the-art of the calcium sulfate formation mechanisms builds upon and goes beyond what we have come to appreciate in the astounding intricacy of other mineral formation processes from ions in aqueous solutions. The original, and rather naive, 'textbook' image of these phenomena, stemming from the adaptation of classical nucleation and growth theories, has increased in complexity due to the discovery of a variety of precursor and intermediate species2. These include solute clusters (e.g. prenucleation clusters, PNCs), liquid(-like) phases, as well as amorphous and nanocrystalline solids etc.. In this context, a number of studies have already revealed that nucleation in the CaSO4-H2O system is non-classical, where the formation of the different crystalline phases involves several steps including a common amorphous precursor1, 3, 4.
In this contribution we show that the formation of the amorphous phase involves the aggregation of small primary particles into larger disordered aggregates exhibiting a "brick-in-the-wall" structure5, 6. The actual crystallization occurs by the restructuring and coalescence of the particles ("bricks") into a given calcium sulfate phase depending on the physicochemical conditions of the solution. Importantly, the rearrangement process does not continue until a (nearly-)perfect homogeneous single crystal is obtained. Instead it comes to a stop, or at least significantly slows down. Such a process thus yields a final imperfect mesocrystal, composed of smaller domains rather than a continuous crystal structure, within which the domains are separated by an amorphous (i.e. less ordered) calcium sulfate phase.
Hence, the non-classical crystallization process of CaSO4 yields a final imperfect mesocrystal with an overall morphology resembling that of a single crystal, yet composed of smaller nano-domains. Importantly, these observations reveal that organic-free calcium sulfate mesocrystals grown by a particle mediated-pathway preserve in the final crystal structure a “memory” or “imprint” of their non-classical nucleation process, something that has been overlooked until now. Furthermore, the nano-scale misalignment of the structural sub-units within these crystals can propagate through the length-scales, and be expressed macroscopically as misaligned zones/domains in large single crystals. Indeed, by considering large anhydrite crystals from the famous Naica Mine (“Cueva de los cristales”) we observed a suite of correlated self-similar void defects spanning multiple length-scales7. These flaws, in the macroscopic crystal, stem from “seeds of imperfection” originating from a particle-mediated nucleation pathway. Hence, building a crystal could be viewed as Nature stacking blocks in a game of Tetris, whilst slowly forgetting the games core concept and failing to fill rows completely.
BIOCIDE
(2022)