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A fast and simple method for sulfur quantification in crude oils was developed by using high-resolution continuum source graphite furnace molecular absorption spectrometry (HR-CS-GFMAS). For this, heavy crude oil samples were prepared as microemulsion (shake) and injected into a graphite furnace (shut). Finally, the concentration of sulfur was determined by monitoring in situ the transient molecular spectrum of GeS at wavelength 295.205nm after adding a germanium solution as molecular forming agent (and go). Zirconium dioxide in the form of nanoparticles (45–55nm) was employed as a permanent modifier of the graphite furnace. Calibration was done with an aqueous solution standard of ammonium sulfate, and a characteristic mass (m0) of 7.5ng was achieved. The effectiveness of the proposed method was evaluated analizing, ten heavy crude oil samples with Sulfur amounts ranging between 0.3 and 4.5% as well as two NIST standard reference materials, 1620c and 1622e. Results were compared with those obtained by routine ICP-OES analysis, and no statistical relevant differences were found.
High-resolution continuum source graphite furnace molecular absorption spectrometry (HR-CS-GF-MAS) was employed for determining adsorbable organic chlorine (AOCl) in water. Organic chlorine was indirectly quantified by monitoring the molecular absorption of the transient aluminum monochloride molecule (AlCl) around a wavelength of 261.42 nm in a graphite furnace. An aluminum solution was used as the molecularforming modifier. A zirconium coated graphite furnace, as well as Sr and Ag solutions were applied as modifiers for a maximal enhancement of the absorption signal. The pyrolysis and vaporization temperatures were 600 °C and 2300 °C, respectively. Non-spectral interferences were observed with F, Br, and I at concentrations higher than 6 mg L-1, 50 mg L-1, and 100 mg L-1, respectively. Calibration curves with NaCl, 4-chlorophenol, and trichlorophenol present the same slope and dynamic range, which indicates the chlorine atom specificity of the method. This method was evaluated and validated using synthetic water samples, following the current standard DIN EN ISO 9562:2004 for the determination of the sum parameter adsorbable organic halides (AOX) for water quality. These samples contain 4-chlorophenol as the chlorinated organic standard in an inorganic chloride matrix. Prior to analysis, organic chlorine was extracted from the inorganic matrix via solid-phase extraction with a recovery rate >95%. There were no statistically significant differences observed between measured and known values and for a t-test a confidence level of 95% was achieved. The limits of detection and characteristic mass were found to be 48 and 22 pg, respectively. The calibration curve was linear in the range 0.1–2.5 ng with a correlation coefficient R2 = 0.9986.
Plants and microorganisms, besides the climate, drive nitrogen (N) cycling in ecosystems. Our objective was to investigate N losses and N acquisition strategies along a unique ecosystem-sequence (ecosequence) ranging from arid shrubland through Mediterranean woodland to temperate rainforest. These ecosystems differ in mean annual precipitation, mean annual temperate, and vegetation cover, but developed on similar granitoid soil parent material, were addressed using a combination of molecular biology and soil biogeochemical tools. Soil N and carbon (C) contents, δ15N signatures, activities of N acquiring extracellular enzymes as well as the abundance of soil bacteria and fungi, and diazotrophs in bulk topsoil and rhizosphere were determined. Relative fungal abundance in the rhizosphere was higher under woodland and forest than under shrubland. This indicates toward plants' higher C investment into fungi in the Mediterranean and temperate rainforest sites than in the arid site. Fungi are likely to decompose lignified forest litter for efficient recycling of litter-derived N and further nutrients. Rhizosphere—a hotspot for the N fixation—was enriched in diazotrophs (factor 8 to 16 in comparison to bulk topsoil) emphasizing the general importance of root/microbe association in N cycle. These results show that the temperate rainforest is an N acquiring ecosystem, whereas N in the arid shrubland is strongly recycled. Simultaneously, the strongest 15N enrichment with decreasing N content with depth was detected in the Mediterranean woodland, indicating that N mineralization and loss is highest (and likely the fastest) in the woodland across the continental transect. Higher relative aminopeptidase activities in the woodland than in the forest enabled a fast N mineralization. Relative aminopeptidase activities were highest in the arid shrubland. The highest absolute chitinase activities were observed in the forest. This likely demonstrates that (a) plants and microorganisms in the arid shrubland invest largely into mobilization and reutilization of organically bound N by exoenzymes, and (b) that the ecosystem N nutrition shifts from a peptide-based N in the arid shrubland to a peptide- and chitin-based N nutrition in the temperate rainforest, where the high N demand is complemented by intensive N fixation in the rhizosphere.
This study focused on quantitative detection of cocaine on Euro banknotes in Germany. A sensitive direct competitive immunoassay was developed and optimized with a limit of detection (LOD) of 5.6 ng/L. Exhaustive cocaine extraction by solvent was tested using different methanol concentrations and buffered solutions. Crossreactivity studies were performed to determine the degree of interference of cocaine metabolites with the immunoassay. Sixty-five Euro banknotes obtained from different districts in Berlin were evaluated. A 100% contamination frequency with cocaine was detected. A comparison between the amount of cocaine extracted by cotton swabbing of one square centimeter of the banknote showed a good correlation for lower contamination levels. This assay showed high sensitivity of detecting pg of cocaine per 1 cm2 of one banknote by swabbing 1 cm2: 0, 14, and 21 pg/cm2. Moreover, three notes of different denominations revealed high cocaine concentration; 1.1 mg/note, and twice 55 μg/note.
In 2018, the production of Municipal SolidWaste (MSW) in EU-28 reached 250.6 Mt, with the adoption of different management strategies, involving recycling (48 wt %), incineration and thermal valorization (29 wt %) and landfilling (23 wt %). This work was based on the analysis of the baseline situation of MSW management in EU-28 in 2018, considering its progress in 2008–2018, and discussed the possible improvement perspectives based on a framework involving incineration and recycling as the only possible alternatives, specifically evaluating the capability of already-existing incineration plants to fulfill the EU needs in the proposed framework. The results of the assessment showed two main crucial issues that could play a pivotal role in the achievement of Circular Economy action plan targets: the need to increase the recycling quotas for specific MSW fractions through the separate collection, and therefore the improvement of definite treatment process chains; the optimization of the recovery of secondary raw materials from incineration bottom ash, involving the Recycling of ferrous and nonferrous metals and the mineral fraction. Both issues need to find an extensive application across all member states to decrease the actual differences in the adoption of sustainable MSW management options.
The main obstacle to bottom ash (BA) being used as a recycling aggregate is the content of salts and potential toxic elements (PTEs), concentrated in a layer that coats BA particles. This work presents a dry treatment for the removal of salts and PTEs from BA particles. Two pilotscale abrasion units (with/without the removal of the fine particles) were fed with different BA samples. The performance of the abrasion tests was assessed through the analyses of particle size and moisture, and that of the column leaching tests at solid-to-liquid ratios between 0.3 and 4.
The results were: the particle-size distribution of the treated materials was homogeneous (25 wt % had dimensions <6.3 mm) and their moisture halved, as well as the electrical conductivity of the leachates. A significant decrease was observed in the leachates of the treated BA for sulphates (44%), chlorides (26%), and PTEs (53% Cr, 60% Cu and 8% Mo). The statistical analysis revealed good correlations between chloride and sulphate concentrations in the leachates with Ba, Cu, Mo, and Sr, illustrating the consistent behavior of the major and minor components of the layer surrounding BA particles. In conclusion, the tested process could be considered as promising for the improvement of BA valorization.
Tracking waterborne microplastic (MP) in urban areas is a challenging task because of the various sources and transport pathways involved. Since MP occurs in low concentrations in most wastewater and stormwater streams, large sample volumes need to be captured, prepared, and carefully analyzed. The recent research in urban areas focused mainly on MP emissions at wastewater treatment plants (WWTPs), as obvious entry points into receiving waters. However, important transport pathways under wet-weather conditions are yet not been investigated thoroughly. In addition, the lack of comprehensive and comparable sampling strategies complicated the attempts for a deeper understanding of occurrence and sources. The goal of this paper is to (i) introduce and describe sampling strategies for MP at different locations in a municipal catchment area under dry and wet-weather conditions, (ii) quantify MP emissions from the entire catchment and two other smaller ones within the bigger catchment, and (iii) compare the emissions under dry and wet-weather conditions. WWTP has a high removal rate of MP (>96%), with an estimated emission rate of 189 kg/a or 0.94 g/[population equivalents (PEQ · a)], and polyethylene (PE) as the most abundant MP. The specific dry-weather emissions at a subcatchment were ≈30 g/(PEQ · a) higher than in the influent of WWTP with 23 g/(PEQ · a). Specific wet-weather emissions from large sub-catchment with higher traffic and population densities were 1952 g/(ha · a) higher than the emissions from smaller catchment (796 g/[ha · a]) with less population and traffic. The results suggest that wet-weather transport pathways are likely responsible for 2–4 times more MP emissions into receiving waters compared to dry-weather ones due to tire abrasion entered from streets through gullies. However, more investigations of wet-weather MP need to be carried out considering additional catchment attributes and storm event characteristics.
Das Element Phosphor ist für alle Lebewesen essenziell und wird beispielsweise von Pflanzen in Form von Phosphaten aufgenommen.
In der landwirtschaftlichen Produktion werden dem Boden die Phosphate durch Wachstum und Ernte der Pflanzen entzogen und müssen ihm in Form von Phosphatdüngemitteln wieder zugeführt werden, um die Nahrungsmittelproduktion zu sichern. Rohphosphat stellt die Grundlage unserer derzeitigen Phosphatdüngemittel dar, ist aber gleichzeitig ein endlicher Rohstoff.
Des Weiteren sind insbesondere sedimentäre Rohphosphate oftmals mit erheblichen Konzentrationen toxischer Schadstoffe wie Cadmium, Uran und Thorium belastet. Eine Kreislaufführung des Phosphats sollte erfolgen, um natürliche Rohstoffvorkommen zu schonen und den Eintrag von Schadstoffen auf unsere Böden zu unterbinden.
Die P-Rückgewinnung aus Teilströmen mit erhöhten P-Gehalten kann direkt in den Kläranlagenbetrieb integriert werden und führt dort in vielen Fällen zu betrieblichen und ökonomischen Vorteilen. Sie ist in der Regel auf Bio-P-Kläranlagen beschränkt, da hier die anaerobe P-Rücklösung initiiert und genutzt werden kann. Durch die reine P-Rücklösung durch Schaffung anaerober Bedingungen ist allerdings das Potential der Rückgewinnung auf 5 bis 15 Prozent der Zulauffracht limitiert.
Die meisten Kläranlagen in Deutschland werden mit einer chemischen Phosphor-Fällung betrieben. Diese Anlagen können aus dem Klärschlamm Phosphat in ausreichend hoher Konzentration nur zurückgewinnen, indem zusätzlich anorganische Säuren wie Schwefelsäure zugeführt werden oder ein Aufschluss mit flüssigem Kohlendioxid stattfindet. Es wird angenommen, dass sich mit diesen Verfahren mehr als 50 Prozent der Zulauffracht einer Kläranlage zurückgewinnen lassen. Der Aufschluss von Klärschlamm mit Schwefelsäure geht aber mit vergleichsweise hohen Umweltwirkungen sowie mit höheren Kosten im Vergleich zu anderen Phosphor-Rückgewinnungsverfahren einher. Ein sehr hohes Potential der Rückgewinnung von Phosphor (P) ist bei allen Verfahren gegeben, die als Rohstoff die Asche aus der Monoverbrennung verwerten. Der Aufschluss mit anorganischen Säuren ermöglicht die sichere Phosphor-Rückgewinnung von mehr als 80% Prozent des Kläranlagenzulaufs. Die Verfahren sind zum Teil großtechnisch umgesetzt oder es befinden sich großtechnische Anlagen im Bau. Auch thermochemische Verfahren wurden entwickelt und deren Einsatzbereitschaft im großtechnischen Maßstab erfolgreich demonstriert. In dem nachfolgenden Beitrag werden unterschiedliche praxiserprobte Verfahren zur Phosphor-Rückgewinnung unter technischen und wirtschaftlichen Aspekten vorgestellt.
Based on recently published research on leaching control mechanisms in electric arc furnace (EAF) slags, it is assumed that a FeO/SiO2 ratio of around one leads to low leached V and Cr concentrations. This ratio influences the mineral phase composition of the slag toward higher amounts of spinel and a lower solubility of calcium silicate phases by suppressing the formation of magnesiowuestite and highly soluble calcium silicate phases. To evaluate this hypothesis, laboratory and scaled up tests in an EAF pilot plant were performed on slag samples characterized by elevated V and Cr leaching and a high FeO/SiO2 ratio. Prior to the melting experiments, the optimum FeO/SiO2 ratio was calculated via FactSageTM. In the melting experiments, the ratio was adjusted by adding quartz sand, which also decreased the basicity (CaO/SiO2) of the slag. As a reference, remelting experiments without quartz sand addition were conducted and additionally, the influence of the cooling rate of the slag was examined. The remelted (without quartz sand) and the remelted modified slags (with quartz sand) were analyzed chemically and mineralogically and the leaching behavior was investigated. The modification of the slags yielded a minimized release of V and Cr, supporting the hypothesis that the FeO/SiO2 ratio influences the mineralogy and the leaching behavior.
Ethnopharmacological relevance: Berberis orthobotrys (BORM) is a medical plant with a long history in traditional usage for the treatment of wounds, cancer, gastrointestinal malady and several other diseases. Our previous studies identified the endemic Pakistani plant Berberis orthobotrys Bien. ex Aitch. as promising source for the treatment of breast cancer and osteosarcoma.
Aim of the study: The present study was aimed to evaluate the anti-cancer properties of 26 plant derived extracts and compounds including the methanolic root extract of Berberis orthobotrys (BORM) on pediatric alveolar rhabdomyosarcoma (RMA), which is known to develop drug resistance, metastatic invasion and potential Tumor progression.
Materials and methods: The main anti-tumor activity of BORM was verified by focusing on morphological, cell structural and metabolic alterations via metabolic profiling, cell viability measurements, flow cytometry, western blotting and diverse microscopy-based methods using the human RMA cell line Rh30.
Results: Exposure of 25 μg/ml BORM exerts an influence on the cell stability, the degradation of oncosomes as well as the shutdown of the metabolic activity of RMA cells, primarily by downregulation of the energy metabolism.
Therefore glycyl-aspartic acid and N-acetyl serine decreased moderately, and uracil increased intracellularly. On healthy, non-transformed muscle cells BORM revealed very low metabolic alterations and nearly no cytotoxic impact. Furthermore, BORM is also capable to reduce Rh30 cell migration (~50%) and proliferation (induced G2/M cycle arrest) as well as to initiate apoptosis confirmed by reduced Bcl-2, Bax and PCNA expression and induced PARP-1 cleavage.
Conclusions: The study provides the first evidence, that BORM treatment is effective against RMA cells with low side effects on healthy cells.
Condensation particle counters (CPCs) are widely used for the measurement of aerosol particle number concentrations in the size range from approximately 3 nm to 3 μm. For an SI-traceable calibration of the size-dependent counting efficiency, which is advisable on a regular basis and required in several applications, Faraday cup aerosol electrometers (FCAEs) are considered to be a suitable SI-traceable reference.While the volumetric aerosol inlet flowrate and the electrical current measurement in FCAEs can be related to respective SI references, inter-comparison exercises for FCAEs are still performed on a regular basis to establish reliable uncertainty budgets and to further investigate the influences of designs and operational parameters on comparability. This is strongly demanded in the international community of metrological institutes and aerosol calibration facilities around the world, which provide CPC calibrations. In the present study, the performance of FCAEs was investigated,using Ag test aerosol particles with a 30 nm particle diameter by varying the inlet flowrates from 0.5 l min−1 to 4 l min−1. From our experimental results, significant deviations were observed in FCAE currents at sample flowrates smaller than 1.5 l min−1. It is recommended that these discrepancies should be quantified before an FCAE is used for CPC calibration at low sample flowrates and small particle sizes in the sub-30 nm size range.
The European Union (EU) has included tributyltin (TBT) and its compounds in the list of priority water pollutants. Quality standards demanded by the EU Water Framework Directive (WFD) require determination of TBT at so low concentration level that chemical analysis is still difficult and further research is needed to improve the sensitivity, the accuracy and the precision of existing methodologies. Within the frame of a joint research project “Traceable measurements for monitoring critical pollutants under the European Water Framework Directive” in the European Metrology Research Programme (EMRP), four metrological and designated institutes have developed a primary method to quantify TBT in natural water using liquid–liquid extraction (LLE) and species-specific isotope dilution mass spectrometry (SSIDMS). The procedure has been validated at the Environmental Quality Standard (EQS) level (0.2 ng L−1 as cation) and at the WFD-required limit of quantification (LOQ) (0.06 ng L−1 as cation). The LOQ of the methodology was 0.06 ng L−1 and the average measurement uncertainty at the LOQ was 36%, which agreed with WFD requirements. The analytical difficulties of the method, namely the presence of TBT in blanks and the sources of measurement uncertainties, as well as the interlaboratory comparison results are discussed in detail.
Stress is a normal part of life for fungi, which can survive in environments considered inhospitable or hostile for other organisms. Due to the ability of fungi to respond to, survive in, and transform the environment, even under severe stresses, many researchers are exploring the mechanisms that enable fungi to adapt to stress. The International Symposium on Fungal Stress (ISFUS) brings together leading scientists from around the world who research fungal stress. This article discusses presentations given at the third ISFUS, held in Sao Jose dos Campos, Sao Paulo, Brazil in 2019, thereby summarizing the state-of-the-art knowledge on fungal stress, a field that includes microbiology, agriculture, ecology, biotechnology, medicine, and astrobiology.
In coastal systems, organisms are exposed to amultitude of stressors whose interactions and effects are poorly studied. Pharmaceutical drugs and Climate Change consequences, such as lowered pH, are examples of stressors affecting marine organisms, as bivalves. Although a vast literature is available for the effects of these stressors when acting individually, very limited information exists on the impacts that the combination of both can have on marine bivalves. For this reason, this study aimed to evaluate the impacts of a simulated ocean acidification scenario (control pH, 8.0; lowered pH, pH 7.6) on the effects of the antiepileptic carbamazepine (CBZ, 1 μg/L) and the antihistamine cetirizine (CTZ, 0.6 μg/L), when acting individually and combined (CBZ + CTZ), on the edible clam Ruditapes philippinarum. After 28 days of exposure, drug concentrations, bioconcentration factors and biochemical parameters related to the clams' metabolic capacity and oxidative stress were evaluated. The results showed that R. philippinarum clams responded differently to pharmaceutical drugs depending on the pH tested, influencing both bioconcentration and biological responses. In general, drug combined treatments showed fewer impacts than drugs acting alone, and acidification seemed to activate at a higher extension the elimination processes that were not activated under control pH. Also, lowered pH per se exerted negative impacts (e.g., cellular damage) on R. philippinarum and the combination with pharmaceutical drugs did not enhance the toxicity.
In the aquatic environment, organisms are exposed to complex mixtures of contaminants which may alter the toxicity profile of each compound, compared to its toxicity alone. Pharmaceutical drugs (e.g. carbamazepine (CBZ) and cetirizine (CTZ)) and metals (e.g. cadmium (Cd)) are among those contaminants that co-occur in the environment. However, most studies concerning their toxicity towards aquatic species are based on single exposure experiments. Thus, the present study aimed to evaluate single and combined effects of Cd and CBZ or CTZ (single conditions: Cd, CTZ, CBZ; combined conditions: CTZ+Cd, CBZ+Cd) on biomarkers related to oxidative stress and energy metabolism in the edible clam Ruditapes philippinarum, by exposing the organisms for 28 days to environmentally relevant concentrations of these contaminants. The biomarkers studied were: i) the electron transport system activity, protein and glycogen contents (indicators of organisms’ metabolic status and energy reserves); ii) lipid peroxidation and the ratio between reduced and oxidized glutathione (indicators of oxidative stress); iii) superoxide dismutase and catalase activities (enzymes indicators of antioxidant defence) and iv) activity of glutathione S-transferases (family of enzymes indicators of biotransformation capacity). Results obtained showed that the uptake of Cd and CBZ was not affected by the combined presence of the contaminants.
However, for CTZ, the uptake was higher in the presence than in the absence of Cd. Concerning toxicity data, in general, the combined exposures (CTZ+Cd, CBZ+Cd) had lower biological effects than the contaminants alone. Nevertheless, our data showed that despite the low concentrations tested, they were enough to exert biological effects that differed between single and combined treatments, evidencing the need to conduct more co-exposure studies to increase the environmental relevance of the gathered data.
Several works evaluated the toxicity of pharmaceutical drugs and climate related changes in invertebrates but few explored the combined effects of both stressors, namely considering their mode of action (MoA). Carbamazepine (CBZ) and cetirizine (CTZ) are pharmaceutical drugs detected in the environment and the toxicity derived from the combined effects of these drugs with ocean acidification (OA) is poorly explored. Thus, the present study investigated the biochemical parameters related to an oxidative stress response and the transcription of genes related to the MoA of CBZ (1.0 mg/L) and CTZ (0.6 mg/L) in the clam Ruditapes philippinarum chronically exposed (28 days) to control (7.8) and low (7.5) pH conditions. The results obtained showed that despite the clams accumulated both drugs, at low pH the clams exposed to CTZ decreased drug concentration and BCF values (CTZ uptake: 2.0 ± 0.5 ng/g fresh weight; BCF: 3.8 ± 0.9) in comparison with clams exposed to control pH (CTZ uptake: 2.9 ± 0.3 ng/g fresh weight; BCF: 5.5 ± 0.6). No oxidative stress was induced by the exposure to CBZ or CTZ at each pH level, but the transcription of several genes related with the MoA (neurotransmission, immunity and biomineralization) was altered by low pH, drug exposure and the combination of both stressors. At both pH conditions, CBZ increased the transcription of GABA receptor gene (neurotransmission) and CTZ led to a decrease of Perlucin gene (biomineralization) transcription. The transcription of MyD88 gene (immunity) decreased at low pH (7.5) combined with drug exposure (CBZ or CTZ). Thus, it was highlighted that the interaction of drug exposure and low pH conditions can change bivalves’ sensitivity to drugs or alter drugs toxicity.
In the aquatic environment, pharmaceutical drugs are submitted to degradation processes, where pho-todegradation is one of the most important mechanisms affecting the fate, persistence and toxicity of thecompounds. Carbamazepine, a widely used antiepileptic, is known to suffer photodegradation in waterbodies and generate photoproducts, some of them with higher potential toxicity than the parent com-pound. Therefore, to evaluate the toxic effects of CBZ when combined with its photoproducts, an acuteexposure (96 h) with the edible clam Scrobicularia plana was performed using environmental concentra-tions of CBZ (0.00–9.00 µg/L) irradiated (and non-irradiated) with simulated solar radiation. The analysisof the irradiated CBZ solutions by mass spectrometry revealed the formation of 5 photoproducts, includ-ing acridine (a compound known to be carcinogenic). Oxidative stress results showed that the exposureto CBZ photoproducts did not increase the toxicity to clams, by comparison with the parent compound.
The occurrence of microplastic (MP) in food products, such as beverages in plastic bottles, is of high public concern. Existing analytical methods focus on the determination of particle numbers, requiring elaborate sampling tools, laboratory infrastructure and generally time-consuming imaging detection methods. A comprehensive routine analysis of MP in food products is still not possible. In the present work, we present the development of a smart filter crucible as sampling and detection tool. After filtration and drying of the filtered-off solids, a direct determination of the MP mass content from the crucible sample can be done by thermal extraction desorption gas chromatography mass spectroscopy (TED-GC/MS). The new filter crucible allows a filtration of MP down to particle sizes of 5 µm. We determined MP contents below 0.01 µg/L up to 2 µg/L, depending on beverages bottle type. This may be directly related to the bottle type, especially the quality of the plastic material of the screw cap. Dependent on the plastic material, particle formation increases due to opening and closing operations during the use phase. However, we have also found that some individual determinations of samples were subjected to high errors due to random events. A conclusive quantitative evaluation of the products is therefore not possible at present.
In recent years, thermoextraction/desorption-gas chromatography/mass spectrometry (TED-GC/MS) has been developed as a rapid detection method for the determination of microplastics (MP) mass contents in numerous environmentally relevant matrices and, in particular, for the measurement of polymers in water samples without time-consuming sample preparation. The TED-GC/MS method was applied to investigate a typical European municipal wastewater system for possible MP masses. Such investigations are important in view of the recent revision of the Urban Wastewater Treatment Directive. Four different representative sampling sites were selected: greywater (domestic wastewater without toilet), combined sewer, and influent and effluent of a wastewater treatment plant (WWTP). All samples were collected by fractional filtration. Filtration was carried out over mesh sizes of 500, 100, 50, and in some cases, 5 µm. Polyethylene (PE), polypropylene (PP), and polystyrene (PS) were detected in all samples, with the PE fraction dominating in all cases. Styrene-butadiene rubber which serves as an indication of tire abrasion, was only found in the influent of the WWTP. The highest MP mass contents were found in the combined sewer, so MP can become a source of pollution during heavy rain events when the capacity limits of the effluent are reached, and the polluted effluent is released uncontrolled into the environment. Based on the studies, MP retention from the WWTP could be estimated to be approximately 96%. Few trends in polymer type or mass contents were detected within the different fractions of the samples or when comparing samples to each other.
Nebulizing of polymer solutions, in a high-voltage field under atmospheric conditions by electrospray ionization (ESI), is a comfortable way to deposit ultra-thin layers of polar or ionic polymers onto any conductive substrate materials. The substrate is grounded and the polymer solution is sprayed through a powered capillary. The formed charged droplets shrink by solvent evaporation during their way to the grounded substrate, the charges close ranks and the droplets collapse consecutively by charge repulsion, thus forming finally charged single macromolecules. After their discharging at the grounded substrate, an ultrathin ‘quasi-monomolecular’ polymer layer is formed. It could be shown by imaging of scratches through the polymer layer by atomic force microscopy that the deposited polymer layers are dense at a thickness of about 10 nm. Carbon fibre bundles were coated with poly (allylamine) (PAAm) or poly(acrylic acid) (PAA) as potential adhesion-promoting layers in fibre–polymer composites. The polymer deposition is self-inhibiting after formation of a continuous coverage of about 200 nm for PAAm and 30 nm for PAA as result of surface charging. Continuous deposition onto such isolating layers or polymers without charging can be achieved by using current of alternating polarity. The film formation is self-healing because of the electrophoretic effect, i.e. the ion discharging occurs preferentially at noncoated areas. This electrophoretic effect of ESI was demonstrated by completely enwrapping all the carbon fibres of the roving within a distance of about 100 μm far from its outside and also at the backside of the fibre bundle with about 80% of the topside coverage, as measured by X-ray photoelectron spectroscopy and visualized using scanning electron microscopy.
Currently, corrosion rates (CR) and/or corrosion products (CP) obtained for methanogen-induced microbiologically influenced corrosion (Mi-MIC) on carbon steel are mainly analyzed from static-incubations. By using a multiport-flow-column, much higher CRs (0.72 mm/yr) were observed, indicating static-incubations are not suitable for determining the corrosive potential of Mi-MIC. With the combination of various analytical methods (ToF-SIMS/SEM-EDS/SEM-FIB) and contrary to previously published data, we observed that CPs contained phosphorus, oxygen, magnesium, calcium and iron but lacked carbon-related species (e.g. siderite). Overall, siderite nucleation is disrupted by methanogens, as they convert aqueous bicarbonate into carbon dioxide for methanogenesis resulting in increased localized corrosion.
Currently, sulfate-reducing bacteria (SRB) is regarded as the main culprit of microbiologically influenced corrosion (MIC), mainly due to the low reported corrosion rates of other microorganisms. For example, the highest reported corrosion rate for methanogens is 0.065 mm/yr. However, by investigating methanogen-induced microbiologically influenced corrosion (Mi-MIC) using an in-house developed versatile multiport flow test column, extremely high corrosion rates were observed. We analyzed a large set of carbon steel beads, which were sectionally embedded into the test columns as substrates for iron-utilizing methanogen Methanobacterium IM1. After 14 days of operation using glass beads as fillers for section separation, the highest average corrosion rate of Methanobacterium IM1 was 0.2 mm/yr, which doubled that of Desulfovibrio ferrophilus IS5 and Desulfovibrio alaskensis 16109 investigated at the same conditions. At the most corroded region, nearly 80% of the beads lost 1% of their initial weight (fast-corrosion), resulting in an average corrosion rate of 0.2 mm/yr for Methanobacterium IM1-treated columns. When sand was used as filler material to mimic sediment conditions, average corrosion rates for Methanobacterium IM1 increased to 0.3 mm/yr (maximum 0.52 mm/yr) with over 83% of the beads having corrosion rates above 0.3 mm/yr. Scanning electron images of metal coupons extracted from the column showed methanogenic cells were clustered close to the metal surface. Methanobacterium IM1 is a hydrogenotrophic methanogen with higher affinity to metal than H2. Unlike SRB, Methanobacterium IM1 is not restricted to the availability of sulfate concentration in the environment. Thus, the use of the multiport flow column provided a new insight on the corrosion potential of methanogens, particularly in dynamic conditions, that offers new opportunities for monitoring and development of mitigation strategies. Overall, this study shows under certain conditions methanogenic archaea can cause higher corrosion than SRB, specific quantifications, i.e., maximum, average, and minimum corrosion rates can be determined, and that spatial statistical evaluations of MIC can be carried out.
Arsenolipids (AsL) of the type arsenic-containing fatty acids (AsFA) and hydrocarbons (AsHC) are natural organoarsenic compounds present in high abundance in seafood. Since little is known about their toxicity, there is a significant concern about their health risk. Here we report the synthesis of two new AsL and their identification in fish by liquid chromatography (LC) coupled simultaneously to inductively coupled plasma mass spectrometry (ICP-MS) and to high resolution mass spectrometry (HR-MS). The molecular structure was elucidated on the basis of their exact mass and their product ion mass spectra. One of the synthesized AsL has been already identified in fish samples, meanwhile, the other arsenolipid is reported here as a natural product in fish.
Arsenic and mercury are frequent contaminants in the environment and care must be taken to limit their entrance into the food chain. The toxicity of both elements strongly depends upon their speciation. Total amounts of As and Hg as well as their species were analyzed in muscle and liver of 26 fishes of seven freshwater fish species caught in the River Elbe. The median concentrations of As were 162 mg kg-1 w.w. in liver and 92 mg kg-1 w.w. in muscle. The median concentrations of total Hg were 241 mg kg-1 w.w. in liver and 256 mg kg-1 w.w. in muscle. While this level of Hg contamination of the freshwater fish in the River Elbe is significantly lower than 20 years ago, it exceeds the recommended environmental Quality standard of 20 mg Hg kg-1 w.w. by a factor of 5e50. However, the European maximum level of 500 mg Hg kg-1 for fish for human consumption is rarely exceeded. Arsenic-containing fatty acids and hydrocarbons were determined and partially identified in methanolic extracts of the fish by HPLC coupled in parallel to ICP-MS (element specific detection) and ESI-Q-TOF-MS (molecular structure detection). While arsenobetaine was the dominant As species in the fish, six arsenolipids were detected and identified in the extracts of liver tissue in common bream (Abramis brama), die (Leuciscus idus), asp (Aspius aspius) and northern pike (Esox lucius). Four arsenic-containing fatty acids (AsFA) and two arsenic-containing hydrocarbons (AsHC) are reported in freshwater fish for the first time. With respect to mercury the more toxic MeHgþ was the Major species in muscle tissue (>90% of total Hg) while in liver Hg2þ and MeHgþ were of equal importance. The results Show the high relevance of element speciation in addition to the determination of total element concentrations to correctly assess the burden of these two elements in fish.
Treatment and reusing of hazardous wastes have become significant issues of modern societies. Blast furnace sludge (BFS) and electric arc furnace dust (EAFD) are such typical wastes, because they usually contain high amounts of undesirable elements such as zinc (Zn) and lead (Pb).
These elements can cause operational problems in reusing of BFS and EAFD. In this study, the Ferro Duo GmbH and the Federal Institute for Materials Research and Testing have investigated a novel approach for eliminating and/or recovering Zn and Pb from both wastes. Applied was a selective chlorination and volatilization of Zn and Pb as chlorides at temperatures between 500 °C and 1100 °C. Both product obtained, Zn and Pb in the form of ZnCl2 and PbCl2 and the purified solid mineral compound are attractive materials for further use. Hydrochloric acid and iron(II) chloride were used as chlorination agents. Exceptionally high Zn and Pb removal efficiencies of >99.5 % could be achieved with both chlorination agents, whereby iron(II) chloride exhibited better performance.
The vibrations of soil and foundations are demonstrated for different types of loading. Train-induced ground vibrations are studied in a measurement campaign where a test train has run with regularly varied speeds. The measured train-induced soil vibration at 2 to 100 m distance from the track is compared with the wave propagation due to hammer excitation and with the theoretical wave field. The strong influence of the soil and the train speed on the amplitudes and frequencies of the vibration has been analysed for passages of the locomotive and the carriages. - The generation of ground vibration by strong explosions has been studied on a large testing area with sandy soil. The propagating waves were measured in a regular grid of measuring points in 10 to 1000 m. Therefore, the dominance of certain waves at certain distances and the changes of compressional waves and Rayleigh waves could clearly be observed. The results are compared with impulse hammer measurements in the range of 5 to 50 m. - A drop test facility has been built on the testing area of the Federal Institute of Materials Research and Testing (BAM). Heavy masses (containers) of up to 200 t can be dropped from 10 m height on a big reinforced concrete foundation. The foundation was instrumented by accelerometers, strain gauges and pressure cells to give information about the loading condition and by geophones to measure the vibration of the surrounding soil and building. Both excitation processes, the release of the mass and the impact, produce high vibration amplitudes. On a smaller drop foundation, the influence of the drop height and the target stiffness has been studied more systematically.
A simple and fast prediction scheme is presented for train induced ground and building vibrations. Simple models such as (1-dimensional) transfer matrices are used for the vehicle-track-soil interaction and for the building-soil interaction. The wave propagation through layered soils is approximated by a frequency-dependent homogeneous half-space. The prediction is divided into the parts “emission” (excitation by railway traffic), “transmission” (wave propagation through the soil) and “immission” (transfer into a building). The link between the modules is made by the excitation force between emission and transmission, and by the free-field vibration between transmission and immission. All formula for the simple vehicle-track, soil and building models are given in this article. The behaviour of the models is demonstrated by typical examples, that is the mitigation of train vibrations by elastic track elements, the low- and high-frequency cut-offs characteristic for layered soils, and the interacting soil, wall and floor resonances of multi-storey buildings. It is shown that the results of the simple prediction models can well represent the behaviour of the more time-consuming detailed models, the finite-element boundary-element models of the track, the wavenumber integrals for the soil, and the three-dimensional finite-element models of the building. In addition, measurement examples are given for each part of the prediction confirming that the methods provide reasonable results. As the prediction models are fast in calculation, many predictions can be done, for example to assess the environmental effect along a new railway line. The simple models have the additional advantage that the user needs to know only a minimum of parameters. So, the prediction is fast and user-friendly, but also theoretically and experimentally well-founded.
Train passages induce forces on the track, train-induced vibrations propagate through the soil and excite neighbouring buildings. The emission, which is the first part of the prediction of vibrations near railway lines, is presented by focusing on the dynamic axle loads. The calculation of the axle loads is based on the vehicle-track-soil interaction. This interaction calculus utilises the dynamic stiffness of the vehicle (the inertia of the wheelset) and the dynamic stiffness of the track-soil system. Based on various time consuming finite-element boundary-element calculations, an approximate track-soil model has been established. The vehicle-track-soil analysis yields several transfer functions between the various geometric or stiffness irregularities and the axle loads of the train. Geometric irregularities of the vehicle (the wheels) and the track (rail surface and track alignment) are the simplest components. Geometric irregularities of the subsoil (trackbed irregularities) have to be transferred to effective irregularities at rail level. The bending stiffness of the track is filtering out the short-wavelength contribution. Stiffness irregularities occur due to random variations in the ballast or the subsoil, which must also be transferred to effective track irregularities, and due to the discrete rail support on sleepers. All necessary transfer functions for the prediction of axle-load spectra are presented as general formula and as specific graphs for differing vehicle and track parameters. The prediction method is applied to a ballast track and a slab track and compared with corresponding axle-box measurements. Moreover, ground vibration measurements at numerous sites are exploited for the axle-load spectra and the validation of the prediction method. All theoretical and experimental results confirm that the dynamic axle-load spectra have an approximate value of 1 kN per third of octave and increase with train speed, track stiffness and around the vehicle-track resonance.
This contribution presents some principles and some examples of the mitigation of railway-induced ground vibrations. The principles are different for the mitigation measures at the track, in the soil or at the building. Force transfer functions of isolated and un-isolated track-soil systems, reflected and transmitted wave amplitudes at walls and trenches in the soil, and the transfer of the (free-field) vibration amplitudes to the foundation amplitudes of the building are analysed. The mitigation effect can be calculated by exact or simplified formulas. Some examples with 3D (finite-element boundary-element), 2D (beam-on-support), and 1D track models, 2D and 1D soil models, detailed 3D building models and finite or infinite 1D wall-floor models are investigated to find out if simple models can be used for a satisfactory prediction of the mitigation effect. The 1D track examples show that the force transfer of the track without vehicle can be exactly calculated, whereas the total force transfer can be calculated approximately if appropriate wheelset masses per track length are used for the isolated and the un-isolated track. The mitigation effect of a filled trench is calculated by a 2D finite element model and the results compare with simple transmission formula if the stiffness per area rather than the wave impedances are used for the infill material. The base isolation of a building is analysed by a detailed 3D model and the results are similar to the analytic results of a single wall with floors on the soil. Other reduction measures as different floor and column dimensions are usually less effective so that the clearly best mitigation solution at a building is a partly or a complete base isolation.
A complex measuring campaign has been performed including the simultaneous measurement of vehicle, track, and soil vibrations during train runs at 16, 25, 40, 63, 80, 100, 125, 140, 160 km/h, and impulse measurements of the passenger car, three track sections and the soil. A ballast track on the soil surface and on a concrete bridge have been investigated as well as a slab track in a tunnel. The evaluation and comparison of all these data shows a generally good agreement for all components if the strong low- and high-frequency cut-off characteristics of the layered and damped soil are incorporated. There is a strong causal correlation between the vehicle and the soil by the dynamic excitation forces and a weak relation between the track and the soil by the axle-sequence spectrum of the train. However, the similarity between the axle-impulse spectrum observed at the track and the spectra of the ground vibration lead to the special excitation component of “scattered axle impulses” which is pre-dominant at the far-field points of the soil.
Measurements on the vehicle-track interaction and the excitation of railway-induced ground vibration
(2017)
Two railway measurement campaigns have been performed in Germany and Switzerland which yield insight in the vehicle-track-soil interaction. The campaign in Germany has included simultaneous measurement of vehicle, track, and soil vibrations during train runs with 16, 25, 40, 63, 80, 100, 125, 140, 160 km/h, and impulse measurements of the passenger car, three track sections and the soil. Two ballast tracks, one on the soil surface and one on a concrete bridge, have been investigated as well as a slab track in a tunnel. Ten different sites in Switzerland have been measured for soil properties and train-induced ground vibrations, which allow to determine the excitation forces of the railway traffic. New axle-box measurements at some of the Swiss sites have been analysed to get further experimental evidence. All these measurements have been evaluated to characterize the excitation processes. Relations between vehicle vibration and ground vibration can be observed. The vehicle vibrations, namely the accelerations of the wheelsets, yield the dynamic forces due to the passage over the irregularities of the vehicle and the track. The ground vibrations are correlated to these dynamic forces to a certain extent. Some mid-frequency ground vibration amplitudes, however, are higher than expected from the dynamic excitation forces. The experimental observations can be explained by an irregular response to the passage of the static loads, that means the passage of the static loads over an irregular ballast or soil. This correct understanding of the excitation processes is important for the prediction as well as for the mitigation of railway induced ground vibrations.
The soil-feeding habit is an evolutionary novelty found in some advanced groups of termites. The study of such groups is important to revealing interesting adaptations to this way-of-life. The genus Verrucositermes is one such example, characterized by peculiar outgrowths on the head capsule, antennae and maxillary palps, which are not found in any other termite. These structures have been hypothesized to be linked to the presence of a new exocrine organ, the rostral gland, whose structure has remained unexplored.
We have thus studied the ultrastructure of the epidermal layer of the head capsule of Verrucositermes tuberosus soldiers.We describe the ultrastructure of the rostral gland, which consists of class 3 secretory cells only. The dominant secretory organelles comprise rough endoplasmic reticulum and Golgi apparatus, which provide secretions delivered to the surface of the head, likely made of peptide-derived components of unclear function. We discuss a possible role of the rostral gland of soldiers as an adaptation to the frequent encounter with soil pathogens during search for new food resources.
Novel agar-based test electrolytes are used to perform electrochemical corrosion investigations on ZnFe and ZnNi binary as well as ZnFeMo ternary zinc coatings. The objectives of the electrochemical investigations include the characterization of the corrosion behavior, the description of the protective effect of the coatings as well as the investigation of the layer formation and degradation under artificial aging. ZnFe and ZnFeMo coatings are applied with varying iron content as well as an additional passivation layer, respectively, to study the effect on corrosion resistance. The results show that the protective effect of the coatings is not negatively influenced by different iron contents or the addition of molybdenum. Additional passivation of the ZnFe-containing coatings by means of a passivating agent leads to a significant improvement in the protective effect. Artificial aging leads to slight degradation of the additional passivation layer whereas coatings without post-treatment enhance their protective effect by the formation of corrosion product layers.
The corrosivity of atmospheres in Europe has changed significantly in recent decades. For the Federal Republic of Germany, no current values for the corrosion rate based on 1‐year atmospheric exposure of standard specimens can be found in the scientific literature after 2000. This paper presents results from a field exposure study in the Berlin metropolitan area and Helgoland in 2016. Based on standard specimens, values for the corrosion rate and the corresponding atmospheric corrosivity category are determined for open exposure and indirect weathering in a ventilated enclosure as sheltering after 1 year of exposure. The results prove that determined corrosivity categories are material‐specific. Sheltered exposure is a typical atmospheric situation for many building components. It allows statements on the effect of the concentration of airborne substances on the corrosivity beyond the normative requirements.
Towards the standardization of biochar analysis: the COST action TD1107 interlaboratory comparison
(2016)
Biochar produced by pyrolysis of organic residues is increasingly used for soil amendment and many other applications. However, analytical methods for its physical and chemical characterization are yet far from being specifically adapted, optimized, and standardized. Therefore, COST Action TD1107 conducted an interlaboratory comparison in which 22 laboratories from 12 countries analyzed three different types of biochar for 38 physical–chemical parameters (macro- and microelements, heavy metals, polycyclic aromatic hydrocarbons, pH, electrical conductivity, and specific surface area) with their preferential methods. The data were evaluated in detail using professional interlaboratory testing software. Whereas intralaboratory repeatability was generally good or at least acceptable, interlaboratory reproducibility was mostly not (20% < mean reproducibility standard deviation < 460%). This paper contributes to better comparability of biochar data published already and provides recommendations to improve and harmonize specific methods for biochar analysis in the future.
The allergenic and inflammatory potential of proteins can be enhanced by chemical modification upon exposure to atmospheric or physiological oxidants. The molecular mechanisms and kinetics of such modifications, however, have not yet been fully resolved. We investigated the oligomerization and nitration of the grass pollen allergen Phl p 5 by ozone (O3), nitrogen dioxide (NO2), and peroxynitrite (ONOO–). Within several hours of exposure to atmospherically relevant concentration levels of O3 and NO2, up to 50% of Phl p 5 were converted into protein oligomers, likely by formation of dityrosine cross-links. Assuming that tyrosine residues are the preferential site of nitration, up to 10% of the 12 tyrosine residues per protein monomer were nitrated. For the reaction with peroxynitrite, the largest oligomer mass fractions (up to 50%) were found for equimolar concentrations of peroxynitrite over tyrosine residues. With excess peroxynitrite, the nitration degrees increased up to 40% whereas the oligomer mass fractions decreased to 20%. Our results suggest that protein oligomerization and nitration are competing processes, which is consistent with a two-step mechanism involving a reactive oxygen intermediate (ROI), as observed for other proteins. The modified proteins can promote pro-inflammatory cellular signaling that may contribute to chronic inflammation and allergies in response to air pollution.
Studies on the development of antibodies for the highly hydrophobic plasticizers DINCH and DEHT
(2018)
Diisononylcyclohexane-1,2-dicarboxylate (DINCH) and di-2-ethylhexyl terephthalate (DEHT), two of the most important substitutes for phthalate plasticizers, are used for a wide range of applications. Consequently, an increasing occurrence in urine and environmental samples is reported. Reliable and fast analytical methods for the quantification of these plasticizers are needed. So far, mainly GC-MS or LC-MS methods are used. We aimed to develop the first antibodies and immunoassays allowing for high-throughput analysis of samples. We designed two DINCH hapten structures and one DEHT hapten structure and employed hapten-protein conjugates for the immunization of rabbits. Sensitive competitive enzyme-linked immunosorbent assays (ELISAs) against each hapten using the produced polyclonal antibodies were established. Yet, binding of DINCH to the respective antibodies was not observed in neither direct nor indirect assay formats, even when using protein conjugates with the heterologous haptens and different carrier proteins in the indirect format. The use of surfactants and solvents in the sample buffer did not result in recognition of the plasticizers. Also, no binding of DEHT in ELISA employing the respective antibodies was detected. We speculate that the production of antibodies against these highly hydrophobic molecules is not possible via our route, however a different hapten design could overcome this obstacle.
Enzyme-linked immunosorbent assay (ELISA) for the anthropogenic marker isolithocholic acid in water
(2016)
Bile acids are promising chemical markers to assess the pollution of water samples with fecal material.
This study describes the optimization and validation of a direct competitive enzyme-linked immunosorbent assay for the bile acid isolithocholic acid (ILA). The quantification range of the optimized Assay was between 0.09 and 15 mg/L. The assay was applied to environmental water samples. Most studies until now were focused on bile acid fractions in the particulate phase of water samples. In order to avoid tedious sample preparation, we undertook to evaluate the dynamics and significance of ILA levels in the aqueous phase. Very low concentrations in tap and surface water samples made a pre-concentration step necessary for this matrix as well as for wastewater treatment plant (WWTP) effluent. Mean recoveries for spiked water samples were between 97% and 109% for tap water and WWTP influent samples and between 102% and 136% for WWTP effluent samples. 90th percentiles of intra-plate and inter-plate coefficients of variation were below 10% for influents and below 20% for effluents and surface water. ILA concentrations were quantified in the range of 33-72 mg/L in influent, 21-49 ng/L in effluent and 18-48 ng/L in surface water samples. During wastewater Treatment the ILA levels were reduced by more than 99%. ILA concentrations of influents determined by ELISA and LC-MS/MS were in good agreement.
However, findings in LC-ELISA experiments suggest that the true ILA levels in concentrated samples are lower due to interfering effects of matrix compounds and/or cross-reactants. Yet, the ELISA will be a valuable tool for the performance check and comparison of WWTPs and the localization of fecal matter input into surface waters.
Flexible, niedrigdichte Schäume aus Biokunststoffen im Extrusionsverfahren herzustellen war bisher industriell noch nicht möglich. Im Verarbeitungstechnikum Biopolymere des Fraunhofer IAP wurde in einem Projekt die Eignung von PBS-basierten Biokunststofftypen für Schaumanwendungen erforscht und weiterentwickelt.
The potential release of hazardous substances from polymer-based products is currently in the focus of environmental policy. Environmental simulations are applied to expose such products to selected aging conditions and to investigate release processes. Commonly applied aging exposure types such as solar and UV radiation in combination with water contact, corrosive gases, and soil contact as well as expected general effects on polymers and additional ingredients of polymer-based products are described. The release of substances is based on mass-transfer processes to the material surfaces. Experimental approaches to investigate transport processes that are caused by water contact are presented. For tailoring the tests, relevant aging exposure types and release quantification methods must be combined appropriately. Several studies on the release of hazardous substances such as metals, polyaromatic hydrocarbons, flame retardants, antioxidants, and carbon nanotubes from polymers are summarized exemplarily. Differences between natural and artificial exposure tests are discussed and demonstrated for the release of flame retardants from several polymers and for biocides from paints. Requirements and limitations to apply results from short-term artificial environmental exposure tests to predict long-term environmental behavior of polymers are presented.
Column leaching tests are frequently used and accepted for investigation of release of hazardous substances from solid materials. Independent of differences due to the field of application or national regulations, column tests assume that local equilibrium is established in the experiment which facilitates transfer of results to field conditions. In the process of harmonization and standardization within Europe the question on the influence of flow rate and grain size distribution on the local equilibrium was raised. Thus, a set of experiments using two different masonry materials with varying grain size distribution and flow rate were conducted including stop/flow experiments. Results are compared to a numerical model which takes intraparticle pore diffusion-controlled release of Mo and V into the percolating water into account. Due to the relatively high intraparticle porosity of the materials (24–29%) data and model indicate that initially equilibrium-state conditions prevail followed by rapidly decreasing concentrations. The model fits data for Mo and V reasonably well; however, after the initial decline of concentrations (at L/S > 2) extended tailing is observed especially of elements occurring as oxides, which is not captured by the model.
Construction products are in contact with water (e.g., rain, seepage water) during their service lifetime and may release potentially harmful compounds by leaching processes. Monitoring studies showed that compounds attributed to construction products are found in storm water and the receiving bodies of water and that the release of biocides in urban areas can be comparable to the input of pesticides from agricultural uses. Therefore, a prospective risk assessment of such products is necessary. Laboratory leaching tests have been developed by the Technical Committee CEN/TC 351 and are ready to use. One major task in the future will be the evaluation of the leaching test results, as concentrations found in laboratory experiments are not directly comparable to the field situations. Another Task will be the selection of compounds to be considered for construction products, which are often a complex mixture and contain additives, pigments, stabilization agents, etc. The formulations of the products may serve as a starting point, but total content is a poor predictor for leachability, and analysis of the eluates is necessary. In some cases, nontargeted approaches might be required to identify compounds in the eluates. In the identification process, plausibility checks referring to available information should be included. Ecotoxicological tests are a complementary method to test eluates, and the combined effects of all compounds—including Degradation products—are included. A bio test battery has been applied in a round robin test and was published in a guidance document. Published studies on the ecotoxicity of construction products show the tests’ suitability to distinguish between products with small and larger effects on the environment.
Background: An Annex XV restriction dossier for cadmium in artists’ paints was submitted by an EU member state to the European Chemicals Agency ECHA. By cleaning used brushes under the tap cadmium can enter the food chain via waste water treatment and subsequent agricultural application of the sewage sludge. It was estimated that 110 kg Cd per year is spread on agricultural land via this exposure route. Other sources of Cd amount to almost 120 tons per year.
Results: The mobility of Cd from pigments was studied in a field-like scenario by leaching experiments using soil samples amended with sewage sludge and spiked with Cd pigments in percolation columns. The redox conditions were confirmed to be the decisive factor for the release of Cd. The release of Cd from artists’ paints was in most cases 1% or lower in the experiments performed.
Conclusions: Application of sewage sludge containing Cd from artist paints does not increase the amount of Cd leached from this soils. Furthermore the quantity of Cd from artists’ paints calculated in the restriction dossier is negligible compared to other sources of Cd to agricultural soil. Therefore ECHA did not consider the proposed restriction to be the most appropriate EU wide measure to address the negligible level of risk.
Recycled plastic granules of high-density polyethylene, polyvinyl chloride and polystyrene the size of microplastics were exposed to artificial aging conditions (2000 h; photooxidative and thermo-oxidative) to simulate their fate outdoors. Their potential to leach into water during the aging process was investigated using column percolation tests.
Aging-related changes on the surface of the material were characterised by IR measurements indicating oxidation reactions with the formation of new adsorption bands (C=O, C–O and OH), especially in the case of photooxidative aging.
These findings were confirmed by the identification of leachable organic compounds. Leaching of total organic carbon, Cl, Ca, Cu and Zn is clearly affected by changes due to aging, and their release is increased after photooxidative aging.
In general, exposure to photooxidative conditions shows a greater influence on aging and thus on leaching and seems to be the more important mechanism for the aging of microplastic in the environment. Comparison with the total content of inorganic species revealed that, for most elements, less than 3% of the total content is released after 2000 h of photooxidative aging.
A “turn-on” fluorescence sensing system based on a BODIPY-cobaloxime complex for the detection of H2S in liquid and gas phase was developed. To that aim, two cobaloxime complexes bearing an axial pyridyl-BODIPY ligand were initially evaluated as sensitive fluorescent HS− indicators in aqueous solution. The sensing mechanism involves the selective substitution of the BODIPY ligand by the HS− anion at the cobalt center, which is accompanied by a strong fluorescence enhancement. The selection of a complex with an ideal stability and reactivity profile toward HS− relied on the optimal interaction between the cobalt metal-center and two different pyridyl BODIPY ligands. Loading the best performing BODIPY-cobaloxime complex onto a polymeric hydrogel membrane allowed us to study the selectivity of the probe for HS− against different anions and cysteine. Successful detection of H2S by the fluorescent “light-up” membrane was not only accomplished for surface water but could also be demonstrated for relevant H2S concentrations in gas phase.
Monitoring the ingestion of microplastics is challenging and suitable detection techniques are insufficiently used. Thus, misidentifying natural for synthetic microfibres cannot be avoided. As part of a framework to monitor the ingestion of microplastics in eelpout, this short report addresses the accurate identification of microfibres. We show that, following visual inspections, putatively synthetic microfibres are indeed of natural origin, as ascertained by spectrometric analyses. Consequently, we call for an inclusion of spectroscopic techniques in standardized microplastic monitoring schemes.
Rising temperatures worldwide pose an increasing challenge for safe and healthy living conditions. Particularly inner cities have been affected by these environmental changes because of the materials used to build houses, streets and infrastructure. The most common building material is concrete. It shows a specific heat capacity, while the heat conductivity for Standard concrete is low. Thus, the use of concrete generates a high capacity of heat storage. In addition, extensive soil sealing also contributes to the temperature rise of inner city areas compared to
their surroundings. To mitigate this so-called urban heat island effect, a self-cooling concrete paver was developed. This paver is able to store water. The evaporation of the water at elevated temperatures provides a cooling effect. This paper focuses on determination of this new paver’s capability to cool the surface and the surrounding. The new paver’s cooling Qualities were analysed in a series of laboratory tests. To prove the results outside of laboratory conditions, two fields (12 m × 8 m) with self-cooling and reference pavers were installed in Spain.
This paper presents and discusses the results of the tests. Correlation between reduced surface temperature of the self-cooling concrete pavers and the air temperature is examined.
Leather is among the most ancient, widely used materials worldwide. Industrial-scale leather production produces large quantities of organic waste attained during shaving and buffing steps during processing. In this study, leather wastes (LW) are used as fillers in flame retarded polymer composites. LW is investigated as a multifunctional bio-filler that enhances the fire performance of flame retarded poly(ethylene–vinyl acetate) (EVA) containing phosphorus flame retardants (P-FRs) ammonium polyphosphate (APP) or a melamine-encapsulated APP (eAPP). Using LW from tanneries as adjuvants to enhance P-FRs in EVA reduces industrial wastes that otherwise require costly waste management solutions. Materials are characterized multi-methodically via mechanical tests, electron microscopy, rheology, thermogravimetric analysis, evolved gas analysis, and condensed phase FTIR, also reaction-to-small-flames and cone calorimeter tests. EVA containing 10 wt-% LW and 20 wt-% P-FRs achieve 20% reductions in fire loads versus EVA, and up to 10% reduction in effective heats of combustion versus EVA with equal (30 wt-%) P-FR loadings. Enhanced char stabilization of EVA composites with LW and P-FRs lowered peaks of heat release rates up to 53% compared to EVA, and up to 40% compared to equal P-FRs loadings. Synergisms between LW and P-FRs in EVA are quantified. A chemical decomposition mechanism is proposed.
Knowledge representation in the Materials Science and Engineering (MSE) domain is a vast and multi-faceted challenge: Overlap, ambiguity, and inconsistency in terminology are common. Invariant (consistent) and variant (context-specific) knowledge are difficult to align cross-domain. Generic top-level semantic terminology often is too abstract, while MSE domain terminology often is too specific. In this paper, an approach how to maintain a comprehensive MSE-centric terminology composing a mid-level ontology–the Platform MaterialDigital Core Ontology (PMDco)–via MSE community-based curation procedures is presented. The illustrated findings show how the PMDco bridges semantic gaps between high-level, MSE-specific, and other science domain semantics. Additionally, it demonstrates how the PMDco lowers development and integration thresholds. Moreover, the research highlights how to fuel it with real-world data sources ranging from manually conducted experiments and simulations with continuously automated industrial applications.
A sedimented freshwater suspended organic matter fortified with particles of polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET) was employed in an interlaboratory comparison of thermoanalytical methods for microplastics identification and quantification. Three laboratories performed pyrolysis gas chromatography-mass spectrometry (Py-GC-MS), three others provided results using thermal extraction desorption followed by gas chromatography coupled to mass spectrometry (TED-GC-MS). One participant performed thermogravimetry-infrared spectroscopy (TGA-FTIR) and two participants used thermogravimetry coupled to mass spectrometry (TGA-MS). Further participants used differential scanning microscopy (DSC), a procedure based on micro combustion calorimetry (MCC) and a procedure based on elemental analysis.
Each participant employed a different combination of sample treatment, calibration and instrumental Settings for polymer identification and quantification. Though there is obviously room for improvements regarding the between-laboratory reproducibility and the harmonization of procedures it was seen that the participants Performing Py-GC-MS, TED-GC-MS, and TGA-FTIR were able to correctly identify all polymers and to report reasonable quantification results in the investigated concentration range (PE: 20.0 μg/mg, PP: 5.70 μg/mg; PS: 2.20 μg/mg, PET: 18.0 μg/mg). Although for the other methods limitations exists regarding the detection of specific polymers, they showed potential as alternative approaches for polymer quantification in solid environmental matrices.
Stir bar sorptive extraction (SBSE) was compared with standardized pump sampling regarding the prospects to assess airborne levels of polycyclic aromatic hydrocarbons (PAHs) in indoor environments. A historic railway water tower, which will be preserved as a technical monument for museum purposes, was sampled with both approaches because the built-in insulationmaterial was suspected to release PAHs to the indoor air. The 16 PAHs on the US EPA list were quantified using gas chromatography with mass spectrometric detection in filters from pump sampling after solvent extraction and on SBSE devices after thermal desorption. SBSEwas seen to sample detectable PAHmasseswith excellent repeatability and a congener pattern largely similar to that observed with pump sampling. Congener patterns were however significantly different from that in the PAH source because release from the insulation material is largely triggered by the respective congener vapor pressures. Absolute masses in the ng range sampled by SBSE corresponded to airborne concentrations in the ng L−1 range determined by pump sampling. Principle differences between SBSE and pump sampling as well as prospects of SBSE as cost-effective and versatile complement of pump sampling are discussed.
The total petrol hydrocarbon (TPH) content in soil is determined by gas chromatographic separation and flame ionisation detection according to ISO 16703 in routine laboratories for about 20 years. The development of the interlaboratory variability observed with this analytical procedure over 15 years in a proficiency testing scheme conducted annually with more than 170 participants is evaluated in detail. A significant improvement of the reproducibility standard deviation among participants is observed over the years and attributed to an increasing familiarity with the procedure. Nevertheless, the determination of TPH in the environmentally relevant mass fraction range between 500 mg/kg and 10 000 mg/kg in soils or sediments is far from reaching the reproducibility standard deviations predicted by the Horwitz curve. It is seen that laboratories with sporadic participation tend to report higher bias, while a core group of laboratories participating on a regular basis arrived at reproducibility standard deviations below 20 %. Results from a given laboratory obtained on two different samples tend to be highly correlated in the same PT round indicating a sound repeatability. Expectedly, the within-laboratory correlation between results from consecutive rounds was considerably lower. However, results from consecutive rounds with a temporal distance of 1, 2 or 3 years revealed largely similar correlations which suggests that the within-laboratory reproducibility adjusts to a constant level at least after a period of 1 year.
Background: Cathodic protection by sacrifcial anodes composed of aluminum-zinc-indium alloys is often applied to protect ofshore support structures of wind turbines from corrosion. Given the considerable growth of renewable energies and thus ofshore wind farms in Germany over the last decade, increasing levels of aluminum, Indium and zinc are released to the marine environment. Although these metals are ecotoxicologically well-studied, data regarding their impact on marine organisms, especially sediment-dwelling species, as well as possible ecotoxicological efects of galvanic anodes are scarce. To investigate possible ecotoxicological efects to the marine environment, the diatom Phaedactylum tricornutum, the bacterium Aliivibrio fscheri and the amphipod Corophium volutator were exposed to dissolved galvanic anodes and solutions of aluminum and zinc, respectively, in standardized laboratory tests using natural seawater. In addition to acute toxicological efects, the uptake of these elements by C. volutator was investigated.
Results: The investigated anode material caused no acute toxicity to the tested bacteria and only weak but signifcant efects on algal growth. In case of the amphipods, the single elements Al and Zn showed signifcant efects only at the highest tested concentrations. Moreover, an accumulation of Al and In was observed in the crustacea species.
Conclusions: Overall, the fndings of this study indicated no direct environmental impact on the tested marine organisms by the use of galvanic anodes for cathodic protection. However, the accumulation of metals in, e.g., crustaceans might enhance their trophic transfer within the marine food web.
A droplet-based microfluidic sensor was developed for the detection of Hg2+ traces in water. The approach uses gated mesoporous nanoparticles loaded with a fluorescent BODIPY dye. The squaraine-based gating mechanism is highly selective for Hg2+ and the indicator release mechanism ensures sensitive detection. The microfluidic system is modular and was assembled from simple PTFE/PFA tubes, while detection was realized with standard optomechanic, optic, and electronic parts. The sensor shows a stable response without memory effects and allows the detection of Hg2+ in water down to 20 ppt.
2,4-D ist ein in der Landwirtschaft weitverbreitetes Pflanzenschutzmittel, das Grundwasser kontaminiert, sich innerhalb der Nahrungskette anreichert und Umwelt- und Gesundheitsprobleme verursachen kann. Hier stellen die Autoren ein mikrofluidisches Nachweissystem für die Echtzeitdetektion von 2,4-D in Grund- oder Oberflächenwasser vor. Es basiert auf der Kombination 2,4-D-selektiver, fluoreszierender, molekular geprägter Polymer-(MIP-)Mikropartikel mit einem 3D-mikrofluidischen Extraktions- und Detektionssystem. Messungen vor Ort sollen damit künftig möglich sein.
A global transition towards more sustainable, affordable and reliable energy systems is being stimulated by the Paris Agreement and the United Nation's 2030 Agenda for Sustainable Development. This poses a challenge for the corrosion industry, as building climate‐resilient energy systems and infrastructures brings with it a long‐term direction, so as a result the long‐term behaviour of structural materials (mainly metals and alloys) becomes a major prospect. With this in mind “Corrosion Challenges Towards a Sustainable Society” presents a series of cases showing the importance of corrosion protection of metals and alloys in the development of energy production to further understand the science of corrosion, and bring the need for research and the consequences of corrosion into public and political focus. This includes emphasis on the limitation of greenhouse gas emissions, on the lifetime of infrastructures, implants, cultural heritage artefacts, and a variety of other topics.
For mobile robots that operate in complex, uncontrolled environments, estimating air flow models can be of great importance. Aerial robots use air flow models to plan optimal navigation paths and to avoid turbulence-ridden areas. Search and rescue platforms use air flow models to infer the location of gas leaks. Environmental monitoring robots enrich pollution distribution maps by integrating the information conveyed by an air flow model. In this paper, we present an air flow modelling algorithm that uses wind data collected at a sparse number of locations to estimate joint probability distributions over wind speed and direction at given query locations. The algorithm uses a novel extrapolation approach that models the air flow as a linear combination of laminar and turbulent components. We evaluated the prediction capabilities of our algorithm with data collected with an aerial robot during several exploration runs. The results show that our algorithm has a high degree of stability with respect to parameter selection while outperforming conventional extrapolation approaches. In addition, we applied our proposed approach in an industrial application, where the characterization of a ventilation system is supported by a ground mobile robot. We compared multiple air flow maps recorded over several months by estimating stability maps using the Kullback-Leibler divergence between the distributions. The results show that, despite local differences, similar air flow patterns prevail over time. Moreover, we corroborated the validity of our results with knowledge from human experts.
While sociality is present in a taxonomically diverse number of species, most animals remain solitary (Bourke, 2011). Over the last centuries, this apparent imbalance in social and non-social animals has led to a great deal of research aimed at shedding light on the biotic and abiotic factors explaining the emergence and maintenance of sociality in nature (West et al., 2015).
Among them, microbes were quickly identified as a major problem for the evolution of social life, because frequent contact between group members typically facilitates the transmission of pathogens, high nest fidelity favours the establishment of microbial pathogens close to their social hosts and, finally, because social groups often exhibit limited genetic diversity and thus limited genetic resistance against certain pathogen strains (Schmid-Hempel, 1998; Cremer et al., 2007). However, this long-standing view has changed considerably over the last few years. Recent research indeed revealed that group living may be more effective than solitary living to Limit the risk of infection by pathogenic microbes because group living also allows the development of an additional layer of defence against pathogens in the form of social immunity (Cremer et al., 2007; Cotter and Kilner, 2010). Under strong pressure from pathogens, microbes could therefore promote, rather than hinder, the evolutionary transition from solitary to group Living (Meunier, 2015; Biedermann and Rohlfs, 2017). Moreover, we are increasingly aware that many microbes provide essential benefits to their hosts by performing critical digestive, physiological, and reproductive functions (Engel and Moran, 2013; McFall-Ngai et al., 2013). The need to Access beneficial microbes may thus have played a role in the expression of frequent and tight interactions between conspecifics and ultimately promoted social evolution (Wilson, 1971; Onchuru et al., 2018). Finally, a growing number of studies suggest that microbes could enforce the Aggregation and expression of cooperative behaviours of the hosts to increase their chance of reaching new hosts and may therefore be involved in the evolution of host sociality (Lewin-Epstein et al., 2017) (but see Johnson and Foster, 2018).
This paper discusses the feasibility of a novel strategy based on the combination of bioprinting nano-doping technology and laser ablation-inductively coupled plasma time-of-flight mass spectrometry analysis for the preparation and characterization of gelatin- based multi-element calibration standards suitable for quantitative imaging. To achieve this, lanthanide up-conversion nanoparticles were added to a gelatin matrix to produce the bioprinted calibration standards. The features of this bioprinting approach were com- pared with manual cryosectioning standard preparation, in terms of throughput, between batch repeatability and elemental signal homogeneity at 5 μm spatial resolution. By using bioprinting, the between batch variability for three independent standards of the same concentration of 89 Y (range 0–600 mg/kg) was reduced to 5% compared to up to 27% for cryosectioning. On this basis, the relative standard deviation ( RSD ) obtained between three independent calibration slopes measured within 1 day also reduced from 16% (using cryosectioning ) to 5% (using bioprinting), supporting the use of a single standard preparation replicate for each of the concentrations to achieve good calibration performance using bioprinting. This helped reduce the analysis time by approximately 3-fold. With cryosectioning each standard was prepared and sectioned individually, whereas using bio-printing it was possible to have up to six different standards printed simultaneously, reducing the preparation time from approximately 2 h to under 20 min (by approxi- mately 6-fold). The bio-printed calibration standards were found stable for a period of 2 months when stored at ambient temperature and in the dark.
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).
Almost 500 municipal solid waste incineration plants in the EU, Norway and Switzerland generate about 17.6 Mt/a of incinerator bottom ash (IBA). IBA contains minerals and metals. Metals are mostly separated and sold to the scrap market and minerals are either disposed of in landfills or utilised in the construction sector. Since there is no uniform regulation for IBA utilisation at EU level, countries developed own rules with varying requirements for utilisation. As a result from a cooperation network between European experts an up-to-date overview of documents regulating IBA utilisation is presented. Furthermore, this work highlights the different requirements that have to be considered. Overall, 51 different parameters for the total content and 36 different parameters for the emission by leaching are defined. An analysis of the defined parameter reveals that leaching parameters are significantly more to be considered compared to total content parameters. In order to assess the leaching behaviour nine different leaching tests, including batch tests, up-flow percolation tests and one diffusion test (monolithic materials) are in place.
A further discussion of leaching parameters showed that certain countries took over limit values initially defined for landfills for inert waste and adopted them for IBA utilisation. The overall utilisation rate of IBA in construction works is approximately 54 wt%. It is revealed that the rate of utilisation does not necessarily depend on how well regulated IBA utilisation is, but rather seems to be a result of political commitment for IBA recycling and economically interesting circumstances.
Tempeh is a common food in Indonesia, produced by fungal fermentation of soybeans using Rhizopus sp., as well as Aspergillus oryzae, for inoculation. Analogously, for economic reasons, mixtures of maize and soybeans are used for the production of so-called tempeh-like products. For maize, a contamination with the mycoestrogen zearalenone (ZEN) has been frequently reported. ZEN is a mycotoxin which is known to be metabolized by Rhizopus and Aspergillus species. Consequently, this study focused on the ZEN transformation during tempeh fermentation. Five fungal strains of the genera Rhizopus and Aspergillus, isolated from fresh Indonesian tempeh and authentic Indonesian inocula, were utilized for tempeh manufacturing from a maize/soybean mixture (30:70) at laboratory-scale. Furthermore, comparable tempeh-like products obtained from Indonesian markets were analyzed. Results from the HPLC-MS/MS analyses show that ZEN is intensely transformed into its metabolites alpha-zearalenol (alpha-ZEL), ZEN-14-sulfate, alpha-ZEL-sulfate, ZEN-14-glucoside, and ZEN-16-glucoside in tempeh production. alpha-ZEL, being significantly more toxic than ZEN, was the main metabolite in most of the Rhizopus incubations, while in Aspergillus oryzae fermentations ZEN-14-sulfate was predominantly formed. Additionally, two of the 14 authentic samples were contaminated with ZEN, alpha-ZEL and ZEN-14-sulfate, and in two further samples, ZEN and alpha-ZEL, were determined. Consequently, tempeh fermentation of ZEN-contaminated maize/soybean mixture may lead to toxification of the food item by formation of the reductive ZEN metabolite, alpha-ZEL, under model as well as authentic conditions.
Zearalenone (ZEN) and its phase II sulfate and glucoside metabolites have been detected in food and feed commodities. After consumption, the conjugates can be hydrolyzed by the human intestinal microbiota leading to liberation of ZEN that implies an underestimation of the true ZEN exposure. To include ZEN conjugates in routine analysis, reliable standards are needed, which are currently not available. Thus, the aim of the present study was to develop a facilitated biosynthesis of ZEN-14-sulfate, ZEN-14-glucoside and ZEN-16-glucoside. A metabolite screening was conducted by adding ZEN to liquid fungi cultures of known ZEN conjugating Aspergillus and Rhizopus strains. Cultivation conditions and ZEN incubation time were varied. All media samples were analyzed for metabolite formation by HPLC-MS/MS. In addition, a consecutive biosynthesis was developed by using Fusarium graminearum for ZEN biosynthesis with subsequent conjugation of the toxin by utilizing Aspergillus and Rhizopus species. ZEN-14-sulfate (yield: 49%) is exclusively formed by Aspergillus oryzae. ZEN-14-glucoside (yield: 67%) and ZEN-16-glucoside (yield: 39%) are formed by Rhizopus oryzae and Rhizopus oligosporus, respectively. Purities of ≥73% ZEN-14-sulfate, ≥82% ZEN-14-glucoside and ≥50% ZEN-16-glucoside were obtained by 1H-NMR. In total, under optimized cultivation conditions, fungi can be easily utilized for a targeted and regioselective synthesis of ZEN conjugates.
The plastic value chain, central part of modern living, caused environmental pollution and bioaccumulation of plastic nanoparticles (PNPs). Their ubiquitous presence in different environmental and biological compartments has become a serious threat to human health and ecosystems. Frequently used plastic materials such as polypropylene (PP), polystyrene (PS) and polyethylene (PE) have been detected in the form of PNPs in the food chain, soil, water and air, as well as in human feces and blood. In this study, we aimed to provide novel insights in endocrine disrupting properties of PNPs using in vitro estrogen receptor (ER) transactivation assay. The effects of PP-NPs, PE-NPs and PS-NPs and their mixture on T47D-KBluc cell line stably transfected with luciferase as reporter enzyme was evaluated by means of cytotoxicity, cellular uptake and ER activation. Tested dose range for PNPs was 0.001 – 10 mg/L. Both cellular uptake and cytotoxicity for all PNPs was found to be dose-dependent. Only the highest dose of PP-NPs and PE-NPs induced apoptosis and cell death, while PS-NPs were not cytotoxic in tested dose range. For tested concentrations, PP-NPs and PE-NPs showed significant agonistic activity on ER, while PS-NPs cannot be considered ER active. When, applied as mixture, PNP demonstrated additive toxicity effects compared to the effect of each individual PNPs. Additivity was also observed for ER agonistic effect of PNPs mixture according to the benchmark dose-addition modelling approach. This study provides missing science-based evidence on endocrine disrupting effects of PE-NPs, PP-NPs, PS-NPs and their mixtures and highlights the importance of considering unintentional, aggregate and combined exposure to different PNPs in risk management.
Zur Weiterentwicklung der Probenpräsentation wurde ein Adapter entwickelt, der Emissionsprüfkammer und Bewertungstrichter miteinander verbindet und dadurch eine der direkten Messung vergleichbare Geruchsbewertung ermöglicht. Die analytischen Messungen zeigen, dass es kaum Unterschiede in der Zusammensetzung der Probenluft in der Kammer im Vergleich zum Probenbehälter gibt. Bei den olfaktorischen Messungen kam es jedoch bei der Bewertung der Probenluft mit Hilfe des Adapters zu Minderbefunden. Anschließende Untersuchungen zeigten, dass beim Ausschalten des Geräts Umgebungsluft über den Trichter in den Adapter strömt und zu einer Verdünnung der Probenluft führt. Um dies zu vermeiden, werden derzeit weitere Messungen durchgeführt.
Eine weitere Versuchsreihe wurde durchgeführt, um den Messaufwand bei der Bewertung der empfundenen Intensität zu reduzieren. Die entwickelte „größer-oder-kleiner/gleich“ Abfrage kann hier hilfreich sein. Die Untersuchungen im Luftqualitätslabor und im Rahmen eines Ringversuches mit verschiedenen Laboren, zeigen, dass die Abfrage in fast allen Fällen zu den gleichen Ergebnissen führt, wie die normgerechte aber aufwendigere Ermittlung der empfundenen Intensität mithilfe des Vergleichsmaßstabes.
Bauprodukte und Einrichtungsgegenstände für Innenräume, wie Bodenbeläge und Wandpaneele, sollen das Wohlbefinden und die Gesundheit der Raumnutzerinnen und -nutzer nicht durch das Ausdünsten von Geruchsstoffen stören. Mit der Geruchsprüfung nach ISO 16000-28 „Innenraumluft - Bestimmung der Geruchsstoffemissionen aus Bauprodukten mit einer Emissionsprüfkammer“ wird der Produktgeruch zu einer messbaren Größe. So kann z. B. die empfundene Intensität, also die Stärke eines Geruchseindruckes, mit Hilfe eines Vergleichsmaßstabes von Probandinnen und Probanden ermittelt werden. Im hier vorgestellten Projekt werden Vorschläge zur Weiterentwicklung der Methode vorgestellt, um im Ergebnis die Reproduzierbarkeit der Messergebnisse weiter zu verbessern. Dabei werden vor allem das Probenpräsentationssystem und die Bewertungsmethodik für die empfundene Intensität bei der Bewertung von Bauprodukten gemäß AgBB-Schema betrachtet, da diese einen wesentlichen Einfluss haben.
The roles extracellular polymeric substances (EPS) play in mineral attachment and weathering were studied using genetically modified biofilms of the rock-inhabiting fungus Knufia petricola strain A95. Mutants deficient in melanin and/or carotenoid synthesis were grown as air-exposed biofilms. Extracted EPS were quantified and characterised using a combination of analytical techniques. The absence of melanin affected the quantity and composition of the produced EPS: mutants no longer able to form melanin synthesised more EPS containing fewer pullulan-related glycosidic linkages. Moreover, the melanin-producing strains attached more strongly to the mineral olivine and dissolved it at a higher rate. We hypothesise that the pullulan-related linkages, with their known adhesion functionality, enable fungal attachment and weathering. The released phenolic intermediates of melanin synthesis in the Δsdh1 mutant might play a role similar to Fe-chelating siderophores, driving olivine dissolution even further. These data demonstrate the need for careful compositional and quantitative analyses of biofilm-created microenvironments.
Melanised cell walls and extracellular polymeric matrices protect rock-inhabiting microcolonial fungi from hostile environmental conditions. How extracellular polymeric substances (EPS) perform this protective role was investigated by following development of the model microcolonial black fungus Knufia petricola A95 grown as a sub-aerial biofilm. Extracellular substances were extracted with NaOH/formaldehyde and the structures of two excreted polymers studied by methylation as well as NMR analyses. The main polysaccharide (~ 80%) was pullulan, also known as α-1,4-; α-1,6-glucan, with different degrees of polymerisation. Αlpha-(1,4)-linked-Glcp and α-(1,6)-linked-Glcp were present in the molar ratios of 2:1. A branched galactofuromannan with an α-(1,2)-linked Manp main chain and a β-(1,6)-linked Galf side chain formed a minor fraction (~ 20%). To further understand the roles of EPS in the weathering of minerals and rocks, viscosity along with corrosive properties were studied using atomic force microscopy (AFM). The kinetic viscosity of extracellular K. petricola A95 polysaccharides (≈ 0.97 × 10-6 m2 s-1) ranged from the equivalent of 2% (w/v) to 5% glycerine, and could thus profoundly affect diffusion-dominated processes. The corrosive nature of rock-inhabiting fungal EPS was also demonstrated by its effects on the aluminium coating of the AFM cantilever and the silicon layer below.
Electron microscopy (EM) is the gold standard for the characterisation of the morphology (size and shape) of nanoparticles. Visual observation of objects under examination is always a necessary first step in the characterisation process. Several questions arise when undertaking to identify and count particles to measure their size and shape distribution. In addition to challenges with the dispersion and identification of the particles, more than one protocol for counting particles is in use. This paper focuses on precise rules for the counting of particles in EM micrographs, as this influences the measurement accuracy of the number of particles, thus implicitly affecting the size values of the counted particles. We review and compare four different, commonly used methods for counting, which we then apply in case studies. The impact of the selected counting rule on the obtained final particle size distribution is highlighted. One main aim of this analysis is to support the application of a specific, well-defined counting approach in accordance with regulatory
requirements to contribute to achieving more reliable and reproducible results. It is also useful for the new harmonised measurement procedures for determining the particle size and particle size distribution of nanomaterials.
The evolution of the crystal structure and crystallographic texture of porous synthetic cordierite was studied by in situ high-temperature neutron diffraction up to 1373 K, providing the first in situ high-temperature texture measurement of this technologically important material. It was observed that the Crystal texture slightly weakens with increasing temperature, concurrently with subtle changes in the crystal structure. These changes are in agreement with previous work, leading the authors to the conclusion that high-temperature Neutron diffraction allows reliable crystallographic characterization of materials with moderate texture. It was also observed that structural changes occur at about the glass transition temperature of the cordierite glass (between 973 and 1073 K).
Crystal structure refinements were conducted with and without quantitative texture analysis being part of the Rietveld refinement, and a critical comparison of the results is presented, contributing to the sparse body of literature on combined texture and crystal structure refinements.
In 2018 municipal solid waste (MSW) incineration in Europe produced nearly 19 Mt of bottom ash (BA); only 46 %-wt. was treated, often in poorly performing plants, leaving behind 10 Mt of untreated and unrecovered BA, destined to landfill. This work was based on the inventory of BA across Europe, and on the hypothesis to achieve complete BA valorisation through two assumptions: treating 100% BA and minimizing the loss of valuable fractions due to technical limitations of state-of-the-art processes in comparison to advanced innovative processes. The research involved three phases: characterization of potential secondary raw materials (metals and mineral fraction) currently lost from untreated (the surplus compared to treatment capacity) and unrecovered BA (the fine fraction) through material flow analysis; environmental assessment (energy balance and net GHG emissions) of complete BA valorisation; investigation of the economic feasibility of complete BA Valorisation through state-of-the-art technologies. The resulting 2.14 Mt loss of valuable materials included 1 Mt Mineral fraction and 0.97 Mt ferrous metals, mostly from untreated BA, and 0.18 Mt non-ferrous metals, mostly from unrecovered BA. The energy balance and GHGs emissions required by the treatment of the currently untreated and unrecovered fractions of BA resulted in energy and GHGs emissions savings. Economic profitability was driven by iron and copper recycling and avoided landfill fees. Profitability was achieved by two thirds of considered countries (average values: NPV 83 M€, ROI 20%, payback time 11 years) with BA mass flow exceeding 0.02 Mt.
Rice is staple food of nearly half the world’s population. Rice yields must therefore increase to feed ever larger populations. By colonising rice and other plants, Herbaspirillum spp. stimulate plant growthand productivity. However the molecular factors involved are largely unknown. To further explore this interaction, the transcription profiles of Nipponbare rice roots inoculated with Herbaspirillum seropedicae were determined by RNA-seq. Mapping the 104 million reads against the Oryza sativa cv. Nipponbare genome produced 65 million unique mapped reads that represented 13,840 transcripts each with at least two-times coverage. About 7.4% (1,014) genes were differentially regulated and of these 255 changed expression levels more than two times. Several of the repressed genes encoded proteins related to plant defence (e.g. a putative probenazole inducible protein), plant disease resistance as well as enzymes involved in flavonoid and isoprenoid synthesis. Genes related to the synthesis and efflux of phytosiderophores (PS) and transport of PS-iron complexes were induced by the bacteria. These data suggest that the bacterium represses the rice defence system while concomitantly activating iron uptake. Transcripts of H. seropedicae were also detected amongst which transcripts of genes involved in nitrogen fixation, cell motility and cell wall synthesis were the most expressed.
In this work, we characterise the performance of a Sharp optical aerosol sensor model GP2Y1010AU0F. The sensor was exposed to different environments: to a clean room, to a controlled atmosphere with known aerosol size distribution and to the ambient atmosphere on a busy city street. During the exposure, the output waveforms of the sensor pulses were digitised, saved and a following offline analysis enabled us to study the behaviour of the sensor pulse-by-pulse. A linear response of the sensor on number concentration of the monosized dispersed PSL particles was shown together with an almost linear dependence on particle diameters in the 0.4 to 4 micrometer range.
The gathered data about the sensor were used to predict its response to an ambient atmosphere, which was observed simultaneously with a calibrated optical particle counter.
Termitidae comprises 80% of all termite species that play dominant decomposer roles in Tropical cosystems. Two major events during Termite evolution were the loss of cellulolytic gut protozoans in the ancestor of Termitidae and the subsequent gain in the termitid subfamily Macrotermitinae of fungal symbionts cultivated externally in ‘‘combs’’ constructed within the nest. How these symbiotic transitions occurred remains unresolved. Phylogenetic analyses of mitochondrial data previously suggested that Macrotermitinae is the earliest branching termitid lineage, followed soon after by Sphaerotermitinae, which cultivates bacterial symbionts on combs inside its nests. This has led to the hypothesis that comb building was an important evolutionary step in the loss of gut protozoa in ancestral termitids. We sequenced genomes and transcriptomes of 55 termite species and reconstructed phylogenetic trees from up to 4,065 orthologous genes of 68 species. We found strong support for a novel sister-group relationship between the bacterial comb-building Sphaerotermitinae and fungus comb-building Macrotermitinae.
This key finding indicates that comb building is a derived trait within Termitidae and that the creation of a comb-like ‘‘external rumen’’ involving bacteria or fungi may not have driven the loss of protozoa from ancestral termitids, as previously hypothesized.
Instead, associations with gut prokaryotic symbionts, combined with dietary shifts from wood to other plant-based substrates, may have played a more important role in this symbiotic transition. Our phylogenetic tree provides a platform for future studies of comparative termite evolution and the evolution of symbiosis in this taxon.
Large animal models are highly recommended for meaningful preclinical studies, including the optimization of cement augmentation for vertebral body defects by vertebroplasty/kyphoplasty.
The aim of this study was to perform a systematic characterization of a strictly minimally invasive in vivo large animal model for lumbar ventrolateral vertebroplasty.
This is a prospective experimental animal study.
Lumbar defects (diameter 5 mm; depth approximately 14 mm) were created by a ventrolateral percutaneous approach in aged, osteopenic, female sheep (40 Merino sheep; 6–9 years; 68–110 kg). L1 remained untouched, L2 was left with an empty defect, and L3 carried a defect injected with a brushite-forming calcium phosphate cement (CPC). Trauma/functional impairment, surgical techniques (including drill sleeve and working canula with stop), reproducibility, bone defects, cement filling, and functional cement augmentation were documented by intraoperative incision-to-suture time and X-ray, postoperative trauma/impairment scores, and ex vivo osteodensitometry, microcomputed tomography (CT), histology, static/fluorescence histomorphometry, and biomechanical testing.
Minimally invasive vertebroplasty resulted in short operation times (28±2 minutes; mean±standard error of the mean) and X-ray exposure (1.59±0.12 minutes), very limited local trauma (score 0.00±0.00 at 24 hours), short postoperative recovery (2.95±0.29 hours), and rapid decrease of the postoperative impairment score to 0 (3.28±0.36 hours). Reproducible defect creation and cement filling were documented by intraoperative X-ray and ex vivo conventional/micro-CT. Vertebral cement augmentation and osteoconductivity of the CPC was verified by osteodensitometry (CPC>control), micro-CT (CPC>control and empty defect), histology/static histomorphometry (CPC>control and empty defect), fluorescence histomorphometry (CPC>control; all p<.05 for 3 and 9 months), and compressive strength measurements (CPC numerically higher than control; 102% for 3 months and 110% for 9 months).
This first-time systematic clinical assessment of a minimally invasive, ventrolateral, lumbar vertebroplasty model in aged, osteopenic sheep resulted in short operation times, rapid postoperative recovery, and high experimental reproducibility. This model represents an optimal basis for standardized evaluation of future studies on vertebral augmentation with resorbable and osteoconductive CPC.
Indonesien gilt aufgrund seiner vielen Vulkane als einer der Hotspots für Geothermie. Doch Salz und Hitze setzen den Geothermie‐Anlagen zu und gefährden ihre Sicherheit und Wirtschaftlichkeit. Ein Team an der BAM hat günstigen, lokal verfügbaren Baustahl jetzt so beschichtet, dass ein nachhaltiger und sicherer Betrieb der Geothermie‐Kraftwerke möglich ist ‐ auch unter Extrembedingungen.
Das BAM‐Team will das Beschichtungssystem nun den Anwendern in Indonesien zur Verfügung stellen, damit es unter Realbedingungen in einem Geothermie‐Kraftwerk getestet werden kann. Der Schutz vor Korrosion ist mitentscheidend, weil sie die Lebensdauer dieser Kraftwerke bestimmt. Unsere Arbeit könnte die Effizienz der Energieproduktion mit Geothermie wesentlich verbessern.
Une transition mondiale vers des systèmes énergétiques plus durables, abordables et fiables a été initiée par l’accord de Paris et l’Agenda 2030 des Nations unies pour un développement durable. Il s’agit là d’un défi industriel majeur car les systèmes et infrastructures énergétiques résilients au changement climatique exigent de se positionner pour le long terme. Se pencher sur le comportement dans la durée des matériaux structurels - principalement des métaux et des alliages - s’impose alors comme une nécessité. Dans cette optique, « La corrosion : un défi pour une société durable »présente une série de cas montrant l’importance de la tenue à la corrosion et de la protection anticorrosion des métaux et des alliages pour le développement de systèmes durables, économiques et fiables de production d’énergie.
Within the framework of precision agriculture, the determination of various soil properties is moving into focus, especially the demand for sensors suitable for in-situ measurements. Energy-dispersive X-ray fluorescence (EDXRF) can be a powerful tool for this purpose. In this study a huge diverse soil set (n = 598) from 12 different study sites in Germany was analysed with EDXRF. First, a principal component analysis (PCA) was performed to identify possible similarities among the sample set.
Clustering was observed within the four texture classes clay, loam, silt and sand, as clay samples contain high and sandy soils low iron mass fractions. Furthermore, the potential of uni- and multivariate data evaluation with partial least squares regression (PLSR) was assessed for accurate Determination of nutrients in German agricultural samples using two calibration sample sets. Potassium and iron were chosen for testing the performance of both models. Prediction of these nutrients in 598 German soil samples with EDXRF was more accurate using PLSR which is confirmed by a better overall averaged deviation and PLSR should therefore be preferred.
Subaerial biofilms (SAB) are an important factor in weathering, biofouling, and biodeterioration of bare rocks, building materials, and solar panel surfaces. The realm of SAB is continually widened by modern materials, and the settlers on these exposed solid surfaces always include melanized, stress-tolerant microcolonial ascomycetes. After their first discovery on desert rock surfaces, these melanized chaetothyrialean and dothidealean ascomycetes have been found on Mediterranean monuments after biocidal treatments, Antarctic rocks and solar panels. New man-made modifications of surfaces (e.g., treatment with biocides or photocatalytically active layers) accommodate the exceptional stress-tolerance of microcolonial fungi and thus further select for this well-protected ecological group. Melanized fungal strains were isolated from a microbial community that developed on highly photocatalytic roof tiles after a long-term environmental exposure in a maritime-influenced region in northwestern Germany. Four of the isolated strains are described here as a novel species, Constantinomyces oldenburgensis, based on multilocus ITS, LSU, RPB2 gene phylogeny. Their closest relative is a still-unnamed rock-inhabiting strain TRN431, here described as C. patonensis. Both species cluster in Capnodiales, among typical melanized microcolonial rock fungi from different stress habitats, including Antarctica. These novel strains flourish in hostile conditions of highly oxidizing material surfaces, and shall be used in reference procedures in material testing.
Afin de garantir la qualité des eaux en Europe, la Commission Européenne a demandé aux États Membres, de leur fournir des résultats de mesure comparables et traçables pour l’analyse des polluants critiques. Devant ces enjeux considérables pour la protection de l’environnement, l’apport de la métrologie est nécessaire pour améliorer la fiabilité des analyses et permettre la comparabilité des résultats. C’est pourquoi, le projet de recherche européen Euramet/EMRP/ENV08 « Traçabilité des mesures pour la surveillance des polluants critiques de la DCE, Directive Cadre européenne sur l’Eau (2000/60/CE) », financé par l’EMRP, avait pour objectif de fournir des éléments pour la mise en place d’une base métrologique. Des méthodes de référence primaires permettant d’analyser des substances dangereuses prioritaires y sont développées pour répondre aux exigences de la DCE en termes de niveaux de performance (limites de quantification et incertitudes). Les hydrocarbures aromatiques polycycliques (HAP), substances dangereuses prioritaires « orphelines » de méthodes DCE compatibles, font partie des polluants ciblés par le projet. Le développement et la validation de la méthode d’analyse des HAP dans l’eau totale ont été réalisés. La méthode qui satisfait au mieux les exigences de la DCE en termes de concentrations et d’incertitudes accessibles est l’extraction en phase solide (SPE) sur un support disque suivie d’une analyse par dilution isotopique associée à la chromatographie en phase gazeuse couplée à la spectroscopie de masse (DI-CG/SM).
Pharmaceuticals, certain food ingredients, and mammalian endogenous metabolic products in wastewater are mostly of human origin. They are anthropogenic markers.
Proper knowledge of their levels in wastewater helps to track sources of pollutants in natural waters and allows for calculation of removal efficiencies in wastewater Treatment plants. Here, we describe the development and application of an indirect competitive, multiplexing suspension Array fluorescence immunoassay (SAFIA) for the detection of carbamazepine (CBZ), diclofenac (DCF), caffeine (CAF), and isolithocholic acid (ILA) in wastewater, covering those classes of anthropogenic markers. The assay consists of haptens covalently conjugated to fluorescence-encoded polystyrene core/silica shell microparticles to create a site for competitive binding of the antibodies (Abs). Bound Abs are then stained with fluorophore-labeled Abs. Encoding and signaling fluorescence of the particles are determined by an automated flow cytometer.
For compatibility of the immunoassay with the 96-well microtiter plate format, a stop reagent, containing formaldehyde, is used. This enables a wash-free procedure while decreasing time-to-result. Detection limits of 140 ± 40 ng/L for CBZ, 180 ± 110 ng/L for CAF, 4 ± 3 ng/L for DCF, and 310 ± 70 ng/L for ILA are achieved, which meet the sensitivity criteria of wastewater analysis. We demonstrate the applicability of SAFIA to real wastewater samples from three different wastewater Treatment plants, finding the results in good agreement with LC-MS/MS. Moreover, the accuracy in general exceeded that from classical ELISAs. We therefore propose SAFIA as a quick and reliable approach for wastewater analysis meeting the requirements for process analytical technology.
Excessive discharge of quaternary ammoniumdisinfectants such as benzalkonium chloride (BAC) into aquatic systems can trigger several physiological responses in environmental microorganisms. In this study, we isolated a less-susceptible strain of Aeromonas hydrophila to BAC, designated as INISA09, froma wastewater treatment plant in Costa Rica. We characterized its phenotypic response upon exposure to three dierent concentrations of BAC and characterizedmechanisms related to its resistance using genomic and proteomic approaches. The genome of the strain, mapped against 52 dierent sequenced A. hydrophila strains, consists of approximately 4.6Mb with 4,273 genes. We found a massive genome rearrangement and thousands of missense mutations compared to the reference strain A. hydrophila ATCC 7966.
We identified 15,762 missense mutations mainly associated with transport, antimicrobial resistance, and outer membrane proteins.
In addition, a quantitative proteomic analysis revealed a significant upregulation of several efflux pumps and the downregulation of porins when the strain was exposed to three BAC concentrations.Other genes related tomembrane fatty acid metabolism and redox metabolic reactions also showed an altered expression.
Our findings indicate that the response of A. hydrophila INISA09 to BAC primarily occurs at the envelop level, which is the primary target of BAC. Our study elucidates the mechanisms of antimicrobial susceptibility in aquatic environments against a widely used disinfectant and will help better understand howbacteria can adapt to biocide pollution. To our knowledge, this is the first study addressing the resistance to BAC in an environmental A. hydrophila isolate. We propose that this bacterial species could also serve as a new model to study antimicrobial pollution in aquatic environments.
Impact of organic phosphates on the structure and composition of short-range ordered iron nanophases
(2024)
Organic phosphates (OP) are important nutrient components for living cells in natural environments, where they readily interact with ubiquitous iron phases such as hydrous ferric oxide, ferrihydrite (FHY). FHY partakes in many key bio(geo)chemical reactions including iron-mediated carbon storage in soils, or iron-storage in living organisms. However, it is still unknown how OP affects the formation, structure and properties of FHY. Here, we document how β-glycerophosphate (GP), a model OP ligand, affects the structure and properties of GP–FHY nanoparticles synthesized by coprecipitation at variable nominal molar P/Fe ratios (0.01 to 0.5). All GP–FHY precipitates were characterized by a maximum solid P/Fe ratio of 0.22, irrespective of the nominal P/Fe ratio. With increasing nominal P/Fe ratio, the specific surface area of the GP–FHY precipitates decreased sharply from 290 to 3 m2 g−1, accompanied by the collapse of their pore structure. The Fe–P local bonding environment gradually transitioned from a bidentate binuclear geometry at low P/Fe ratios to monodentate mononuclear geometry at high P/Fe ratios. This transition was accompanied by a decrease in coordination number of edge-sharing Fe polyhedra, and the loss of the corner-sharing Fe polyhedra. We show that Fe(III) polymerization is impeded by GP, and that the GP–FHY structure is highly dependent on the P/Fe ratio. We discuss the role that natural OP-bearing Fe(III) nanophases have in biogeochemical reactions between Fe–P and C species in aquatic systems.
Silver nanoparticles (AgNPs) nowadays appear in close to 24% of consumer products that contain engineered nanomaterials. Thus, they are expected to be released into the environment, where their fate and effect are still undetermined. Considering the evidenced efficacy of the single particle Inductively Coupled Plasma – Mass Spectrometry (sp ICP-MS) technique in the study of nanomaterials, this work reports on the use of sp ICP-MS along with an online dilution sample introduction system for the direct analysis of untreated and spiked seawater samples, as part of a larger scale experiment studying the fate of Ag (ionic and nanoparticles) in seawater mesocosm systems. Silver nanoparticles coated with branched polyethyleneimine (BPEI@AgNPs) or ionic silver (Ag+) were introduced gradually into the seawater mesocosm tanks at very low, environmentally relevant concentrations (50 ng Ag L− 1 per day, for 10 consecutive days, up to a total of 500 ng Ag L− 1 ), and samples were collected and analyzed daily, within a consistent time window. Using very low detector dwell time (75 μs) and specialized data treatment, information was obtained on the nanoparticles’ size distribution and particle number concentration, as well as the ionic silver content, of both the AgNPs and the Ag+ treated seawater mesocosm tanks. The results for the AgNP treated samples indicated the rapid degradation of the added silver particles, and the subsequent increase of ionic silver, with recoveries close to 100% for the first days of the experiment. On the other hand, particle formation was observed in the Ag+ treated seawater tanks, and even though the number concentration of silver-containing nanoparticles increased throughout the experiment, the amount of silver per particle remained relatively constant from the early days of the experiment. In addition, the online dilution sample introduction system for the ICP-MS proved capable of handling the untreated seawater matrix without significant contamination issues and downtime, while the low dwell time and data treatment procedure developed were shown to be suitable for the analysis of nanomaterials at the low nm-scale, despite the complex and heavy matrix introduced into the ICP-MS.
The most massive design on the Baltic shore used geosynthetic materials, the landslide protection construction in Svetlogorsk (1300 m long, 90,000 m2 area, South-Eastern Baltic, Kaliningrad Oblast, Russian Federation) comprises the geotextile and the erosion control geomat coating the open-air cliff slopes. Due to changes in elastic properties during long-term use in the open air, as well as due to its huge size, this structure can become a non-negligible source of microplastic pollution in the Baltic Sea. Weather conditions affected the functioning of the structure, so it was assessed that geosynthetic materials used in this outdoor (open-air) operation in coastal protection structures degraded over time. Samples taken at points with different ambient conditions (groundwater outlet; arid places; exposure to the direct sun; grass cover; under landslide) were tested on crystallinity and strain at break. Tests showed a 39–85% loss of elasticity of the polymer filaments after 3 years of use under natural conditions. Specimens exposed to sunlight are less elastic and more prone to fail, but not as much as samples taken from shaded areas in the grass and under the landslide, which were the most brittle.
The database gives information on the contamination of the shore of the South-Eastern Baltic with the debris of geosynthetic materials for the period 2018–2020. This new type of coastal pollution enters the natural environment due to the destruction of coastal protection structures and construction activities. The database contains sections:
(1) a list of types of geosynthetic material residues, their photographic images and photographs illustrating examples of finds in natural conditions
[1 List_geosynthetic_debris_SEB],
(2) monitoring data on the contamination of the beach strip with the debris of geotextiles, braids from gabions, geocontainers (big bags), geocells and geogrids for the beaches of the South-Eastern Baltic for the period 2018–2020
[2 Monitoring_geosynthetic_debris_SEB];
(3) statistical distributions of the found geosynthetic debris by size
[3 Scales_geosynthetic_debris_SEB] and (4) results of test surveys on the shores of Lithuania and Poland adjacent to Kaliningrad Oblast.
All data refer to the beaches of the Kaliningrad Oblast (Russia), including the Russian parts of the Vistula and Curonian Spits, but also contains information on a one-time assessment of the pollution of the beaches of the adjacent territories: the Polish shore from the Poland-Russia border on the Vistula Spit to the mouth of the Vistula River, the Lithuanian shore from the border Lithuania-Russia on the Curonian Spit to the border of Latvia-Lithuania. Materials were collected during field surveys within the ERANET-RUS_Plus joint project EI-GEO, ID 212 (RFBR 18-55-76002 ERA_a, BMBF 01DJ18005).
A novel mesoporous silica material containing boron–dipyrromethene (BODIPY) moieties (I) is employed for the detection of nerve agent simulants (NASs) and the organophosphate nerve or chemical warfare agents (CWAs) Sarin (GB), Soman (GD), and Tabun (GA) in aqueous environments. The reactive BODIPY dye with an optimum positioned hydroxyl group undergoes acylation reactions with phosph(on)ate substrates, yielding a bicyclic ring. Due to aggregation of the dyes in water, the sensitivity of the free dye in solution is very low. Only after immobilization of the BODIPY moieties into the silica substrates is aggregation inhibited and a sensitive determination of the NASs diethyl cyanophosphonate (DCNP), diethyl chlorophosphate (DCP) and diisopropyl fluorophosphate (DFP) possible. The signaling mode is a strong quenching of the fluorescence, reaching LODs in the pM range. The best performing hybrid material was singled out from a library of hybrid silicas varying in morphology and surface functionalization. The response to actual CWAs such as GB, GD, and GA has also been tested, offering similar behavior as for the simulants. The proposed reaction mechanism has been verified by investigation of other model materials, containing for instance BODIPY moieties without an optimum hydroxyl group (III) or a BODIPY dye with an all-aliphatic counterpart (IV). The latter can only form a monocyclic reaction product, showing much less reactivity as I. Assays with other possible competitors have been additionally carried out, showing favorably low cross-reactivities. Finally, the determination of NASs in several natural waters has been demonstrated.
Invited for this month’s cover picture is the group of Dr. Knut Rurack at the Department of Analytical Chemistry; Reference Materials at the Bundesanstalt fuer Materialforschung und -pruefung (BAM) in Berlin (Germany). The cover picture shows how differences in color and fluorescence on a test strip can be easily read out with a mobile device. Two reference spots Frame the sensitive spot that indicates the presence of trace amounts of HgII below the threshold in a natural water sample. This dipstick contains a hybrid material that combines boron-dipyrromethene (BODIPY) probes sterically loaded into specifically tailored mesoporous silica particles, allowing for ultrasensitive HgII detection through enhanced fluorescence in a few seconds. The applicability in real water samples and fish extracts are also studied.
The synthesis, characterization, and application of mesoporous materials containing boron–dipyrromethene (BODIPY) moieties that allow the sensitive and selective detection of HgII in aqueous environments by fluorescence enhancement is reported. For this purpose, BODIPY dye I containing a thia‐aza crown ether receptor as the fluorescent probe for the detection of HgII in aqueous environments is encapsulated into mesoporous materials to avoid self‐quenching or aggregation in water. Determination of HgII is accomplished within a few seconds with high selectivity and sensitivity, reaching a limit of detection of 12 ppt. The determination of trace amounts of HgII in natural waters and in fish extracts is demonstrated by using our sensing material. The incorporation of the material into several μ‐PAD strips yields a portable, cheap, quick, and easy‐to‐handle tool for trace HgII analysis in water.
DNA long-term stability and integrity is of importance for applications in DNA based bio-dosimetry, data-storage, pharmaceutical quality-control, donor insemination and DNA based functional nanomaterials. Standard protocols for these applications involve repeated freeze-thaw cycles of the DNA, which can cause detrimental damage to the nucleobases, as well as the sugar-phosphate backbone and therefore the whole molecule. Throughout the literature three hypotheses can be found about the underlying mechanisms occurring during freeze-thaw cycles. It is hypothesized that DNA single-strand breaks during freezing can be induced by mechanical stress leading to shearing of the DNA molecule, by acidic pH causing damage through depurination and beta elimination or by the presence of metal ions catalyzing oxidative damage via reactive oxygen species (ROS). Here we test these hypotheses under well defined conditions with plasmid DNA pUC19 in high-purity buffer (1xPBS) at physiological salt and pH 7.4 conditions, under pH 6 and in the presence of metal ions in combination with the radical scavengers DMSO and Ectoine. The results show for the 2686 bp long plasmid DNA, that neither mechanical stress, nor pH 6 lead to degradation during repeated freeze-thaw cycles. In contrast, the presence of metal ions (Fe2+) leads to degradation of DNA via the production of radical species.
The pressing need for novel bioproduction approaches faces a limitation in the number and type of molecules accessed through synthetic biology. Halogenation is widely used for tuning physicochemical properties of molecules and polymers, but traditional halogenation chemistry often lacks specificity and generates harmful by-products. Here, we pose that deploying synthetic metabolism tailored for biohalogenation represents an unique opportunity towards economically attractive and environmentally friendly organohalide production. On this background, we discuss growth-coupled selection of functional metabolic modules that harness the rich repertoire of biosynthetic and biodegradation capabilities of environmental bacteria for in vivo biohalogenation. By rationally combining these approaches, the chemical landscape of Living cells can accommodate bioproduction of added-value organohalides which, as of today, are obtained by traditional chemistry.
Caffeine is known to be one of the most consumed psychoactive drugs. For this reason, caffeine is continuously released into the environment with potential impacts on inhabiting organisms. The current study evaluated the biochemical alterations induced in the clam species Ruditapes philippinarum after exposure for 28 days to caffeine (0.5, 3.0 and 18.0 mg/L). The results obtained showed that, with the increasing caffeine concentrations, an increase in clams defense mechanisms (such as antioxidant and biotransformation enzymes activity) was induced which was accompanied by an increase in protein content. Nevertheless, although an increase on defense mechanisms was observed, clams were not able to prevent cells from lipid peroxidation that increased with the increase of caffeine concentration. Furthermore, with the increase of exposure concentrations, clams increased their metabolic activity (measured by electron transport activity), reducing their energy reserves (glycogen content), to fight against oxidative stress. Overall, the present study demonstrated that caffeine may impact bivalves, even at environmentally relevant concentrations, inducing oxidative stress in organisms. The present study is an important contribution to address knowledge gaps regarding the impacts of long-term exposures to pharmaceuticals since most of the studies assessed the effects after acute exposures, most of them up to 96 h.
Materials that confer antimicrobial activity, be that by innate property, leaching of biocides or design features (e.g., non-adhesive materials) continue to gain popularity to combat the increasing and varied threats from microorganisms, e.g., replacing inert surfaces in hospitals with copper. To understand how efficacious these materials are at controlling microorganisms, data is usually collected via a standardised test method. However, standardised test methods vary, and often the characteristics and methodological choices can make it difficult to infer that any perceived antimicrobial activity demonstrated in the laboratory can be confidently assumed to an end-use setting. This review provides a critical analysis of standardised methodology used in academia and industry, and demonstrates how many key methodological choices (e.g., temperature, humidity/moisture, airflow, surface topography) may impact efficacy assessment, highlighting the need to carefully consider intended antimicrobial end-use of any product.
Social insects employ a range of behaviours to protect their colonies against disease, but little is known about how such collective behaviours are orchestrated. This is especially true for the social Blattodea (termites). We developed an experimental approach that allowed us to explore how the social response to disease is co-ordinated by multistep host-pathogen interactions. We infected the eastern subterranean termite Reticulitermes flavipes with the entomopathogenic fungus Metarhizium anisopliae, and then, at different stages of infection, reintroduced them to healthy nestmates and recorded behavioural responses. As expected, termites groomed pathogen-exposed individuals significantly more than controls; however, grooming was significantly elevated after fungal germination than before, demonstrating the importance of fungal status to hygienic behaviour. Significantly, we found that cannibalism became prevalent only after exposed termites became visibly ill, highlighting the importance of host condition as a cue for social hygienic behaviour. Our study reveals the presence of a coordinated social response to disease that depends on stage of infection. Specifically, we show how the host may play a key role in triggering its own sacrifice. Sacrificial self-flagging has been observed in other social insects: our results demonstrate that termites have independently evolved to both recognize and destructively respond to sickness.
Two novel species of the fungal genus Ochroconis, O. lascauxensis and O. anomala have been isolated from the walls of the Lascaux Cave, France. The interest in these fungi and their melanins lies in the formation of black stains on the walls and rock art which threatens the integrity of the paintings. Here we report solid-state cross polarization magic-angle spinning 13C and 15N nuclear magnetic resonance (NMR) spectroscopy and surface-enhanced Raman spectroscopy (SERS) of the melanins extracted from the mycelia of O. lascauxensis and O. anomala in order to known their chemical structure. The melanins from these two species were compared with those from other fungi. The melanins from the Ochroconis species have similar SERS and 13C and 15N NMR spectra. Their chemical structures as suggested by the data are not related to 3,4-dihydroxyphenylalanine, 5,6-dihydroxyindole or 1,8-dihydroxynaphthalene precursors and likely the building blocks from the melanins have to be based on other phenols that react with the N-terminal amino acid of proteins. The analytical pyrolysis of the acid hydrolysed melanin from O. lascauxensis supports this assumption.
Microplastics can affect biophysical properties of the soil. However, little is known about the cascade of events in fundamental levels of terrestrial ecosystems, i.e., starting with the changes in soil abiotic properties and propagating across the various components of soil−plant interactions, including soil microbial communities and plant traits. We investigated here the effects of six different microplastics (polyester fibers, polyamide beads, and four fragment types: polyethylene, polyester terephthalate, polypropylene, and polystyrene) on a broad suite of proxies for soil health and performance of spring onion (Allium fistulosum). Significant changes were observed in plant biomass, tissue elemental composition, root traits, and soil microbial activities. These plant and soil responses to microplastic exposure were used to propose a causal model for the mechanism of the effects. Impacts were dependent on particle type, i.e., microplastics with a shape similar to other natural soil particles elicited smaller differences from control. Changes in soil structure and water dynamics may explain the observed results in which polyester fibers and polyamide beads triggered the most pronounced impacts on plant traits and function. The findings reported here imply that the pervasive microplastic contamination in soil may have consequences for plant performance and thus for agroecosystems and terrestrial biodiversity.
Soils are essential components of terrestrial ecosystems that experience strong pollution pressure. Microplastic contamination of soils is being increasingly documented, with potential consequences for soil biodiversity and function. Notwithstanding, data on effects of such contaminants on fundamental properties potentially impacting soil biota are lacking. The present study explores the potential of microplastics to disturb vital relationships between soil and water, as well as its consequences for soil structure and microbial function. During a 5-weeks garden experiment we exposed a loamy sand soil to environmentally relevant nominal concentrations (up to 2%) of four common microplastic types (polyacrylic fibers, polyamide beads, polyester fibers, and polyethylene fragments). Then, we measured bulk density, water holding capacity, hydraulic conductivity, soil aggregation, and microbial activity. Microplastics affected the bulk density, water holding capacity, and the functional relationship between the microbial activity and water stable aggregates. The effects are underestimated if idiosyncrasies of particle type and concentrations are neglected, suggesting that purely qualitative environmental microplastic data might be of limited value for the assessment of effects in soil. If extended to other soils and plastic types, the processes unravelled here suggest that microplastics are relevant long-term anthropogenic stressors and drivers of global change in terrestrial ecosystems.
A similar secretome disturbance as a hallmark of non-pathogenic Botrytis cinerea ATMT-mutants?
(2019)
The gray mold fungus Botrytis cinerea is a necrotrophic pathogen able to infect
hundreds of host plants, including high-value crops such as grapevine, strawberry and tomato. In order to decipher its infectious strategy, a library of 2,144 mutants was generated by random insertional mutagenesis using Agrobacterium tumefaciensmediated transformation (ATMT). Twelve mutants exhibiting total loss of virulence toward different host plants were chosen for detailed analyses. Their molecular characterization revealed a single T-DNA insertion in different loci. Using a proteomics approach, the secretome of four of these strains was compared to that of the parental strain and a common profile of reduced lytic enzymes was recorded. Significant variations in this profile, notably deficiencies in the secretion of proteases and hemicellulases, were observed and validated by biochemical tests. They were also a hallmark of the remaining eight non-pathogenic strains, suggesting the importance of these secreted Proteins in the infection process. In the twelve non-pathogenic mutants, the Differentiation of infection cushions was also impaired, suggesting a link between the Penetration structures and the secretion of proteins involved in the virulence of the pathogen.
Pyrotechnic smoke generators fall under the Directive 2013/29/EU in Europe and could potentially belong to all categories except consumer fireworks. These types are especially present in the field of “Other Pyrotechnic Articles” of the categories P1 and P2, e.g. as simulation devices for paintball or airsoft gaming. The specific users of these products are aware of the corresponding smoke liberation during use and usually wear protective equipment to minimize exposure to potentially harmful aerosols. However, such products are often misused against the labelling requirements in locations where these articles are not supposed to be used, like football stadiums and demonstrations. In contrast to the intended use, uninvolved third parties are likely exposed to these reaction products without proper protective equipment. This study aims at identifying the transient particle size range of the aerosols emitted during the functioning of such common smoke generators for simulation purposes. In total four different types of articles were investigated, with five colors per type (white, blue, green, red, orange). Results show that the majority of the particles were emitted in a range between 40 nm and 350 nm, with some variation depending on the smoke color. Particles with diameters of less than 100 nm are generally of specific concern, as they can penetrate the alveolar system of the human lungs and therefore present a specific hazard.