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Einstufung von Aschen und Schlacken aus der Abfallverbrennung im Hinblick auf die weitere Verwertung
(2024)
There are two mirror entries in the European Waste Catalogue for bottom ash and slag from waste incineration: 19 01 11* and 19 01 12. Entry 19 01 11* describes a waste material containing hazardous substances. It was shown that only the hazardous property HP14 (ecotoxic) is of relevance for the classification. If substances with the hazard statement code (HSC) H400, H410, H411, H412 and H413 are present in incineration bottom ash (IBA) above certain level the waste is classified as hazardous, otherwise it is non-hazardous (in this case 19 01 12). It was further shown that only Cu, Zn and Pb compounds have an impact on the classification using a summation rule: 100xΣ c(H410) + 10xΣ c(H411) + Σ c(H412). Limit value is 25 percent. It is obvious that H410 substances have the highest impact. Therefore, the knowledge of the elemental composition of IBA is not sufficient because the content of distinct chemical compounds (with the respective molecular weight) is needed. When the exact speciation is not known a worst-case approach has to be applied. A practical guideline for the estimation of HP14 was developed based on the definition of 4 substance groups: 1. Metals and alloys, 2. Water-soluble substances, 3. Oxides and carbonates and 4. Substances not soluble in weak acids. In substance group 1 only fine Zn powder has the HSC H410. Water-soluble substances are assumed to be H410 substances. Their concentrations are, however, regularly below the cut-off value of 0.1 %. The amount of substance group 3 is estimated by a selective extraction with maleic acid. According to the worst-case approach it is assumed that CuCO3xCu(OH)2 and ZnO represent the respective Cu and Zn species in IBA because these substances have the highest stochiometric factor. Even with this worst-case approach results from operators of IBA treatment plant showed that the limit value of 25 % is not exceeded.
The requirements for utilization of IBA in Germany are defined in the Secondary
Building Materials Decree (Ersatzbaustoffverordnung EBV) which was set into force in August 2023. Leaching methods (batch test or column test) with a liquid-to-solid ratio of 2 l/kg are applied. IBA fulfills the requirements for class HMVA-2. Actually, even a classification of IBA as hazardous (i.e 19 01 11*) would not affect utilization but handling and transport.
Here, we report a comparative study of different sum parameter analysis methods for the extraction of per- and polyfluoroalkyl substances (PFAS) from manufactured consumer products, which can be measured by combustion ion chromatography (CIC). Therefore, a hydrolysis-based extraction method was further developed, which accounts for the addition of hydrolyzable covalently bound polyfluoroalkylated side-chain polymers (SFPs) to the extractable organic fluorine portion of the mass balance proposed as "hydrolyzable organically bound fluorine" (HOF). To test this hypothesis, the method was applied to 39 different consumer products containing fluoropolymers or monomeric PFAS taken from four different categories: outdoor textiles, paper packaging, carpeting, and permanent baking sheets. We also evaluated the method's efficiency by extracting four synthesized fluorotelomer polyacrylate reference compounds. The total fluorine (TF) and extractable organically bound fluorine (EOF) values were measured through CIC using established protocols. The TF values ranged from sub-ppb to %-levels, depending on the compound class. All samples showed results for hydrolyzed organofluorine (HOF) between 0.03 and 76.3 μg/g, while most EOF values were lower (<LOD to 58.1 μg/g). Moreover, the methods were contrasted with the "total hydrolyzable precursor" (THP) assay analyzed using gas-chromatography coupled mass spectrometry (GC-MS), which yielded concentrations of 6:2–10:2 fluorotelomer alcohols (<LOD-568 μg/g) for textile and paper samples. Furthermore, targeted analytical investigation of 25 compounds via liquid chromatography coupled tandem mass spectrometry (LC-MS/MS) was conducted and accounted for significantly lower sum amounts (<LOD-0.98 μg PFAS/g). To estimate the fluorine mass balance of all methods, the fluorine levels of target analytical data were calculated and compared to the sum parameter values and evaluated. Finally, the efficiency of the extraction method was approximated by the recovery analysis of four selected SFP model compounds compared to their TF values, yielding 36.7–74.0% after extraction and 3.8–36.3% after processing the extract for the HOF sum parameter.
Im Folgenden soll über aktuelle Diskussionen und Arbeitsschwerpunkte im Fachbeirat der BAM und von der Zulassungsstelle berichtet werden. Es werden Änderungen im Zusammenhang mit der Zulassungsrichtlinie für Kunststoffdichtungsbahnen vorgestellt. Es wird über die aktuelle Diskussion über die Anforderungen z. B. an metallische Sensoren für Dichtungskontrollsysteme berichtet. Änderungen der Fremdprüfung von sogenannten Sandschutzmatten, des Standards zur Qualitätsüberwachung (SQÜ) von Kunststoff Dränelementen (KDE) und der Anpassung der Formulierungen zum Überbau der in Abdichtungen verwendeten Produkte werden aufgezeigt.
Im Folgenden soll über aktuelle Diskussionen und Arbeitsschwerpunkte im Fachbeirat der BAM und von der Zulassungsstelle berichtet werden. Es werden Änderungen im Zusammenhang mit der Zulassungsrichtlinie für Kunststoffdichtungsbahnen vorgestellt. Es wird über die aktuelle Diskussion über die Anforderungen z. B. an metallische Sensoren für Dichtungskontrollsysteme berichtet. Änderungen der Fremdprüfung von sogenannten Sandschutzmatten, des Standards zur Qualitätsüberwachung (SQÜ) von Kunststoff Dränelementen (KDE) und der Anpassung der Formulierungen zum Überbau der in Abdichtungen verwendeten Produkte werden aufgezeigt.
The chemical state of antimony and vanadium species in municipal solid waste incineration bottom ash
(2023)
Due to the large quantity as residual mineral waste, municipal solid waste incineration - bottom ash (MSWI-BA) is an interesting secondary raw material that can be utilized for road construction. However, leaching of chloride, sulfate and potentially hazardous heavy metals from MSWSI-BA into the environment may cause problems in utilization of it in civil engineering. In a previous study, we performed a long-term leaching test of MSWI-BA in a lysimeter for almost six years to investigate the efficiency of the treatment process on the release of hazardous substances. While concentrations of chloride, sulfate and the majority of the heavy metals started to decrease rapidly with progressive liquid-to-solid ratio (L/S), the ecotoxic hazardous elements antimony (Sb) and vanadium (V) behaved differently. To unravel these unusual release behaviors and the oxyanion-formation of Sb and V we will apply HERFD-XANES spectroscopy to analyze their chemical state.
Throughout their life cycles—from production, usage, through to disposal—materials and products interact with the environment (water, soil, and air). At the same time, they are exposed to environmental influences and, through their emissions, have an impact on the environment, people, and health. Accelerated experimental testing processes can be used to predict the long-term environmental consequences of innovative products before these actually enter the environment.
We are living in a material world. Building materials, geosynthetics, wooden toys, soil, nanomaterials, composites, wastes and more are research subjects examined by the authors of this book. The interactions of materials with the environment are manifold. Therefore, it is important to assess the environmental impact of these interactions. Some answers to how this task can be achieved are given in this Special Issue.
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.
Per- and polyfluoroalkyl substances (PFAS) are a large group of more than 10,000 anionic, cationic, zwitterionic or neutral organofluorine surfactants. As a result of continuous and prolific use, mainly in aviation firefighting foams, thousands of industrial and military installations have been found to contain contaminated soil, groundwater and surface water. While liquid chromatography tandem mass spectrometry (LC-MS/MS) is commonly used technique to characterize targeted PFAS in environmental samples, there are more than 10,000 different PFAS known, which have various headgroups and properties. Therefore, several analytical techniques are available to analyse various groups or pools of PFAS or “all” PFAS as a sum parameter. Current decontamination strategies of PFAS-burdened soils mainly consist of adsorption methods using adsorbents for fixation of PFAS in the ground. A second option is the utilization of a “pump and treat” process, cycling polluted soils through a washing plant leading to the concentration of the pollutants in the fine fraction. Both approaches are cost-intensive and not intended for the direct decomposition of all PFAS contaminants. Hence, there is a great demand for innovative developments and chemical treatment technologies, dealing with new strategies of tackling the PFAS problem. Previously, mechanochemical treatment of polychlorinated organic compounds in soils showed an efficient dechlorination. Thus, we investigated mechanochemical treatment of PFAS contaminated soils with various additives in a ball mill and analyzed the PFAS defluorination with gas chromatography mass spectrometry (GC-MS) and liquid chromatography tandem mass spectrometry (LC-MS/MS), respectively, as well es the fluoride mineralization by ion chromatography (IC) and fluorine K-edge X-ray absorption near-edge structure (XANES) spectroscopy.
Research on per- and polyfluoroalkyl substances (PFAS) frequently incorporates organofluorine measurements, particularly because they could support a class-based approach to regulation. However, standardized methods for organofluorine analysis in a broad suite of matrices are currently unavailable, including a method for extractable organofluorine (EOF) measured using combustion ion chromatography (CIC). Here, we report the results of an international interlaboratory comparison. Seven laboratories representing academia, government, and the private sector measured paired EOF and PFAS concentrations in groundwater and eel (Anguilla rostrata) from a site contaminated by aqueous film-forming foam. Among all laboratories, targeted PFAS could not explain all EOF in groundwater but accounted for most EOF in eel. EOF results from all laboratories for at least one replicate extract fell within one standard deviation of the interlaboratory mean for groundwater and five out of seven laboratories for eel. PFAS spike mixture recoveries for EOF measurements in groundwater and eel were close to the criterion (±30%) for standardized targeted PFAS methods. Instrumental operation of the CIC such as replicate sample injections was a major source of measurement uncertainty. Blank contamination and incomplete inorganic fluorine removal may introduce additional uncertainties. To elucidate the presence of unknown organofluorine using paired EOF and PFAS measurements, we recommend that analysts carefully consider confounding methodological uncertainties such as differences in precision between measurements, data processing steps such as blank subtraction and replicate analyses, and the relative recoveries of PFAS and other fluorine compounds.
Aschen und Schlacken aus der thermischen Abfallbehandlung enthalten eine Vielzahl von Schwermetallverbindungen. Für Antimon, Chrom, Kupfer, Molybdän und Vanadium werden in der neuen Ersatzbaustoffverordnung (Bundesregierung, 2021) Eluatgrenzwerte für die Verwertung festgelegt. Aschen und Schlacken werden aus der Abfallverbrennungsanlage nass ausgetragen und vor einer Verwertung in der Regel mehrere Wochen gelagert. Dabei finden hydraulische Reaktionen statt und enthaltenes CaO wird zu einem Großteil in Calciumcarbonat umgewandelt. Während wässrige Eluate von frischen Aschen pH-Werte von 12 und höher aufweisen, sind die Eluate nach einigen Wochen weniger stark alkalisch. Die gemessenen Schwermetallkonzentrationen sind daher dann auch deutlich niedriger, mit Ausnahme von Antimon (Sb) und Vanadium (V). Hier steigen die Konzentration mit der Lagerungsdauer. Grund sind sinkende Konzentrationen von Ca-Ionen, die sonst zu einer Ausfällung von Antimonaten und Vanadaten führen. Zu hohe Eluatwerte von Sb und V können jedoch durch Sorption an Eisenoxidverbindungen gemindert werden. Dazu wurden Sorptionsexperimente mit verschiedenen Eisenoxidverbindungen durchgeführt.
Aschen und Schlacken aus der thermischen Abfallbehandlung enthalten eine Vielzahl von Schwermetallverbindungen. Für Antimon, Chrom, Kupfer, Molybdän und Vanadium werden in der neuen Ersatzbaustoffverordnung Eluatgrenzwerte für die Verwertung festgelegt. Aschen und Schlacken werden aus der Abfallverbrennungsanlage nass ausgetragen und vor einer Verwertung in der Regel mehrere Wochen gelagert. Dabei finden hydraulische Reaktionen statt und enthaltenes CaO wird zu einem Großteil in Calciumcarbonat umgewandelt. Während wässrige Eluate von frischen Aschen pH-Werte von 12 und höher aufweisen, sind die Eluate nach einigen Wochen weniger stark alkalisch. Die gemessenen Schwermetallkonzentrationen sind daher dann auch deutlich niedriger, mit Ausnahme von Antimon (Sb) und Vanadium (V). Hier steigen die Konzentration mit der Lagerungsdauer. Grund sind sinkende Konzentrationen von Ca-Ionen, die sonst zu einer Ausfällung von Antimonaten und Vanadaten führen. Zu hohe Eluatwerte von Sb und V können durch Sorption an Eisenoxidverbindungen gemindert werden. Als besonders wirkungsvoll hat sich Schwertmannit (Eisen-Oxyhydroxysulfat) erwiesen. Es entsteht durch Oxidation von pyrithaltigem Material durch Mikroorganismen und wird deshalb in Gebieten gefunden, in denen Braunkohle abgebaut wurde, z.B. in der Lausitz. Weitere untersuchte Eisenoxidverbindungen waren Hämatit und Schlämme aus der Abtrennung von Eisen und Mangan in Wasserwerken.
Per- and polyfluoroalkyl substances (PFAS) are widely used for durable water-repellent finishing of different fabrics and textiles like outdoor clothing, carpets, medical textiles and more. Existing PFAS extraction techniques followed by target analysis are often insufficient in detecting widely used side-chain fluorinated polymers (SFPs) that are barely or non-extractable. SFPs are typically copolymers consisting of a non-fluorinated backbone with perfluoroalkyl side-chains to obtain desired properties. We compared the accessible analytical information and performance of complementary techniques based on oxidation (dTOP assay, PhotoTOP), hydrolysis (THP assay), standard extraction, extractable organic fluorine (EOF), and total fluorine (TF) with five functional textiles and characterized 7 further textiles only by PhotoTOP oxidation. The results show that when applied directly to textile samples, oxidation by dTOP and PhotoTOP and also hydrolysis by the THP are able to capture large fractions of the TF in form of perfluoroalkyl side-chains present in the textiles while methods relying on extracts (EOF, target and non-target analysis) were much lower (e.g., factor ~25-50 lower). The conversion of large fractions of the measured TF into PFCAs or FTOHs from fluorinated side chains is in contrast to previous studies. Concentrations ranged from <LOQ to over ~1000 mg F/kg after oxidation/hydrolysis and <LOQ to over 2000 mg F/kg for TF, while EOF and target PFAS in extracts were detected at much lower concentrations (up to ~ 60 mg F/kg) (amount of fluorine in the order: extraction << EOF << oxidation/hydrolysis ≤ TF). Perfluoroalkyl carboxylic acids (PFCAs) and fluorotelomer alcohols (FTOHs) from THP and PhotoTOP both represented the chain-length distribution in the textiles showing that long-chain SFPs are still used in current textiles. Further advantages and disadvantages of the applied methods are discussed.
Das Recycling von gemischten Baustoffen führt neben der Herstellung von Gesteinskörnungen parallel zu einem stärker schadstoffbelasteten Stoffstrom, der circa ein Drittel der ursprünglichen Masse ausmacht. Dieser sogenannte Brechsand endet derzeit in der Deponierung und wird somit der Kreislaufwirtschaft entzogen. Der vorliegende Beitrag untersucht nun die Aufbereitung dieses Materials unter Verwendung einer Setzmaschine im Pilotmaßstab. Hierbei wird die Eignung dieser Technik evaluiert und das Aufbereitungsprodukt als möglicher Ersatzbaustoff untersucht.
Kunststoffdichtungsbahnen (KDB) aus PE-HD (Polyethylen hoher Dichte) werden häufig zur Abdichtung von Bauwerken in der Geotechnik verwendet. Diese Produkte werden aus einem Kunststoff mit relativ komplexer Zusammensetzung hergestellt. Um eine Aussage über die Haltbarkeit von KDB aus PE-HD treffen zu können, muss das Materialverhalten berücksichtigt werden. In diesem Zusammenhang sind die wichtigsten Aspekte der Dauerhaftigkeit die Spannungsrissbeständigkeit und die Beständigkeit gegen Oxidation. Verschiedene PE-Sorten weisen eine unterschiedliche Spannungsrissbeständigkeit auf. Um dieser Eigenschaft von PE-HD zu begegnen, werden nur KDB aus sehr hochwertigen Rohstoffen zugelassen. Auf der anderen Seite werden hohe Anforderungen an die umgebenden Schichten, wie Auflager und Schutzschicht gestellt, um möglichst geringe Spannungen zu erzeugen und damit Dehnungen die Dehnungen der KDB gering zu halten. Bestimmte Medien, die bei den betreffenden Prüfungen verwendet werden, dürfen nicht mehr in der EU in Verkehr gebracht werden. Im Folgenden sollen die Zusammenhänge in Kürze dargestellt werden.
Darüber hinaus sollen Diskussionen und Änderungen im Zusammenhang mit der Zulassungsrichtlinie für KDB vorgestellt werden. Der aktuelle Stand der Diskussion im Zusammenhang mit den verwendeten Tensiden in Bezug auf die Spannungsrissprüfung und weiterer Prüfungen wird aufgezeigt. Änderungen der Fremdprüfung von sogenannten Sandschutzmatten, des Standards zur Qualitätsüberwachung (SQÜ) von Kunststoff Dränelementen (KDE) und der Anpassung der Formulierungen zum Überbau der in Abdichtungen verwendeten Produkte werden in Kürze aufgezeigt.
Kunststoffdichtungsbahnen (KDB) aus PE-HD (Polyethylen hoher Dichte) werden häufig zur Abdichtung von Bauwerken in der Geotechnik verwendet. Diese Produkte werden aus einem Kunststoff mit relativ komplexer Zusammensetzung hergestellt. Um eine Aussage über die Haltbarkeit von KDB aus PE-HD treffen zu können, muss das Materialverhalten berücksichtigt werden. In diesem Zusammenhang sind die wichtigsten Aspekte der Dauerhaftigkeit die Spannungsrissbeständigkeit und die Beständigkeit gegen Oxidation. Verschiedene PE-Sorten weisen eine unterschiedliche Spannungsrissbeständigkeit auf. Um dieser Eigenschaft von PE-HD zu begegnen, werden nur KDB aus sehr hochwertigen Rohstoffen zugelassen. Auf der anderen Seite werden hohe Anforderungen an die umgebenden Schichten, wie Auflager und Schutzschicht gestellt, um möglichst geringe Spannungen zu erzeugen und damit Dehnungen die Dehnungen der KDB gering zu halten. Bestimmte Medien, die bei den betreffenden Prüfungen verwendet werden, dürfen nicht mehr in der EU in Verkehr gebracht werden. Im Folgenden sollen die Zusammenhänge in Kürze dargestellt werden.
Darüber hinaus sollen Diskussionen und Änderungen im Zusammenhang mit der Zulassungsrichtlinie für KDB vorgestellt werden. Der aktuelle Stand der Diskussion im Zusammenhang mit den verwendeten Tensiden in Bezug auf die Spannungsrissprüfung und weiterer Prüfungen wird aufgezeigt. Änderungen der Fremdprüfung von sogenannten Sandschutzmatten, des Standards zur Qualitätsüberwachung (SQÜ) von Kunststoff Dränelementen (KDE) und der Anpassung der Formulierungen zum Überbau der in Abdichtungen verwendeten Produkte werden in Kürze aufgezeigt.
The amount of plant-available phosphorus (P) in soil strongly influences the yield of plants in agriculture. Therefore, various simple chemical extraction methods have been developed to estimate the plant-available P pools in soil. More recently, several experiments with the DGT technique have shown that it has a much better correlation to plant-available P in soils than standard chemical extraction methods (e.g. calcium-acetate-lactate (CAL), Colwell, Olsen, water) when soils with different characteristics are considered. However, the DGT technique cannot give information on the plant-available P species in the soil. Therefore, we combined DGT with solution 31P nuclear magnetic resonance (NMR) spectroscopy. This was achieved by using a modified DGT device in which the diffusive layer had a larger pore size, the binding layer incorporated an adsorption material with a higher capacity, and the device had a larger exposure area. The spectroscopic investigation was undertaken after elution of the deployed DGT binding layer in a NaOH solution. Adsorption tests using solutions of known organic P compounds showed that a sufficient amount of these compounds could be adsorbed on the binding layer in order for them to be analyzed by solution 31P NMR spectroscopy. Furthermore, various intermediates of the hydrolysis of trimetaphosphate in soil could be also analyzed over time.
Per- and polyfluoroalkyl substances (PFAS) are a large group of organofluorine surfactants used in the formulations of thousands of consumer goods. The continuous use of PFAS in household products and the discharge of PFAS from industrial plants into the sewer system have been resulted in contaminated effluents and sewage sludge from wastewater treatment plants (WWTPs) which became an important pathway for PFAS into the environment. Because sewage sludge is often used as fertilizer its application on agricultural soils has been observed as significant input path for PFAS into our food chain. To produce high-quality phosphorus fertilizers for a circular economy from sewage sludge, PFAS and other pollutants (e.g. pesticides and pharmaceuticals) must be separated from sewage sludge. Normally, PFAS are analyzed using PFAS protocols typically with time-consuming extraction steps and LC-MS/MS target quantification. However, for screening of PFAS contaminations in wastewater-based fertilizers also the DGT technique can be used for the PFAS extraction. Afterwards, combustion ion chromatography (CIC) can be applied to analyze the “total” amount of PFAS on the DGT binding layer. The DGT method was less sensitive and only comparable to the extractable organic fluorine (EOF) method values of the fertilizers in samples with >150 µg/kg, because of different diffusion properties for various PFAS, but also kinetic exchange limitations. However, the DGT approach has the advantage that almost no sample preparation is necessary. Moreover, the PFAS adsorption on the DGT binding layer was investigated via surface sensitive spectroscopical methods, such as Fourier-transform infrared (FT-IR) and fluorine K-edge X-ray absorption near-edge structure (XANES) spectroscopy.
Thermo-Desorption Gas Chromatography-Mass Spectrometry (TD-GC-MS) was used to investigate the thermal degradation of two different polyurethanes (PU). PU samples were heated at different heating rates and the desorbed products were collected in a cold injection system and thereafter submitted to GC-MS. Prospects and limitations of the detection and quantification of semi-volatile degradation products were investigated. A temperature dependent PU depolymerization was
found at temperatures above 200 °C proved by an increasing release of 1,4-butanediol and methylene diphenyl diisocyanate (MDI) representing the main building blocks of both polymers. Their release was monitored quantitatively based on external calibration with authentic compounds. Size Exclusion Chromatography (SEC) of the residues obtained after thermodesorption confirmed the initial competitive degradation mechanism indicating an equilibrium of crosslinking and depolymerization as previously suggested. Matrix-Assisted Laser Desorption Ionization (MALDI) mass spectrometry of SEC fractions of thermally degraded PUs provided additional hints on degradation mechanism.
For the first time, µ-X-ray fluorescence (µ-XRF) mapping combined with fluorine K-edge µ-X-ray absorption near-edge structure (µ-XANES) spectroscopy was applied to depict per- and polyfluoroalkyl substances (PFAS) contamination and inorganic fluoride in samples concentrations down to 100 µg/kg fluoride. To demonstrate the matrix tolerance of the method, several PFAS contaminated soil and sludge samples as well as selected consumer product samples (textiles, food contact paper and permanent baking sheet) were investigated. µ-XRF mapping allows for a unique element-specific visualisation at the sample surface and enables localisation of fluorine containing compounds to a depth of 1 µm. Manually selected fluorine rich spots were subsequently analysed via fluorine K-edge µ-XANES spectroscopy. To support spectral interpretation with respect to inorganic and organic chemical distribution and compound class determination, linear combination (LC) fitting was applied to all recorded µ-XANES spectra. Complementarily, solvent extracts of all samples were target-analysed via LC-MS/MS spectrometry. The detected PFAS sum values range from 20 to 1136 µg/kg dry weight (dw). All environmentally exposed samples revealed higher concentration of PFAS with a chain length >C8 (e.g. 580 µg/kg dw PFOS for Soil1), whereas the consumer product samples showed a more uniform distribution with regard to chain lengths from C4 to C8. Independent from quantified PFAS amounts via target analysis, µ-XRF mapping combined with µ-XANES spectroscopy was successfully applied to detect both point-specific concentration maxima and evenly distributed surface coatings of fluorinated organic contaminants in the corresponding samples.
Wie können industriell synthetisierte Schadstoffe aus einer Stoffklasse quantifiziert werden, deren genauer Umfang unbekannt ist und auf mehrere tausend Verbindungen geschätzt wird? Im Falle der per- und polyfluorierten alkylierten Substanzen (PFAS) stellen sich Wissenschaftler*innen weltweit seit über zehn Jahren diese Frage. Neben der etablierten Methodik der Einzelstoffanalytik (engl. target analytic) existieren Summenparameteranalysen zur Quantifizierung
organisch gebundener fluorierter Verbindungen in Umweltmedien und Konsumprodukten. An der Bundesanstalt für Materialforschung und -prüfung (BAM) beschäftigen wir uns mit der Weiterentwicklung von Summenparametermethoden am Beispiel von PFAS-belasteten Umweltkompartimenten wie Böden, Klärschlämmen und Gewässerproben sowie PFAS-haltigen Konsumgütern. In diesem Beitrag stellen wir zwei ausgewählte Fallbeispiele vor und diskutieren die Vor- und Nachteile der Methoden im Vergleich zur Einzelstoffanalytik.
Solid wastewater-based fertilizers were screened for per- and polyfluoroalkyl substances (PFAS) by the extractable organic fluorine (EOF) sum parameter method. The EOF values for ten sewage sludges from Germany and Switzerland range from 154 to 7209 mg kg−1. For thermal treated sewage sludge and struvite the EOF were lower with values up to 121 mg kg−1. Moreover, the application of PFAS targeted
and suspect screening analysis of selected sewage sludge samples showed that only a small part of the EOF sum parameter values can be explained by the usually screened legacy PFAS. The hitherto unknown part of EOF sum parameter contains also fluorinated pesticides, pharmaceutical and aromatic compounds. Because these partly fluorinated compounds can degrade to (ultra-)short PFAS in wastewater treatment plants they should be considered as significant sources of organic fluorine in the environment. The combined results of sum parameter analysis and suspect screening reveal the need to update current regulations, such as the German fertilizer ordinance, to focus not solely on a few selected PFAS such as perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) but
consider an additional sum parameter approach as a more holistic alternative. Moreover, diffusion gradient in thin-films (DGT) passive samplers were utilized as an alternative simplified extraction method for PFAS in solid wastewater-based fertilizers and subsequently quantified via combustion ion chromatography. However, the DGT method was less sensitive and only comparable to the EOF values
of the fertilizers in samples with >150 mg kg−1, because of different diffusion properties for various PFAS, but also kinetic exchange limitations.
Per- and polyfluoroalkyl substances (PFAS) are chemicals which were developed to improve humanity’s quality of life. Due to their high chemical stability and resistance to degradation by heat or acids, PFAS were used in a variety of consumer products. The continuous use of PFAS in household products and the discharge of PFAS from industrial plants into the sewer system resulted in the contamination of effluents and sewage sludge from wastewater treatment plants (WWTPs) (Roesch et al. 2022). Since sewage sludge is often used as fertilizer, its application on agricultural soils has been observed as a significant entry path for PFAS into the environment, specifically in our food chain. In Germany the sewage sludge/biosolid application on agricultural land was banned with the amendment of the German Sewage Sludge Ordinance and by 2029 sewage sludge application will be totally prohibited. However, phosphorus (P) from sewage sludge should still be recycled in WWTPs of cities with a population larger than 50,000 residents. To produce high-quality P-fertilizers for a circular economy, PFAS and other pollutants (e.g. pesticides and pharmaceuticals) must be separated from sewage sludge. Due to the strong diversity of industrial PFAS usage it is not clear if a safe application of novel recycled P-fertilizers from WWTPs can be guaranteed. Therefore, we analyzed various sewage sludges and wastewater-based fertilizers. Sewage sludge (SL) samples from various WWTPs in Germany and Switzerland, six sewage sludge ashes (SSA) from Germany, six thermally treated SL and SSA samples with different additives (temperatures: 700-1050 °C), two pyrolyzed SL samples (temperature: 400 °C) and two struvite samples from Germany and Canada were analyzed. The goal was to quantify PFAS in sewage sludges and wastewater-based P-fertilizers with the sum parameter extractable organic fluorine (EOF) by combustion ion chromatography (CIC). The results were compared with data from classical LC-MS/MS target analysis as well as selected samples by HR-MS suspect screening. The EOF values of the SLs mainly range between 154 and 538 µg/kg except for one SL which showed an elevated EOF value of 7209 µg/kg due to high organofluorine contamination. For the SSA samples the EOF values were lower and values between LOQ (approx. 60 µg/kg) and 121 µg/kg could be detected. For the pyrolyzed SLs no EOF values above the LOQ were detected. Moreover, the two wastewater-based struvite fertilizers contain 96 and 112 µg/kg EOF, respectively. In contrast to the EOF values, the sum of PFAS target values were relatively low for all SLs. Additional applied PFAS HR-MS suspect screening aimed to tentatively identify PFAS that could contribute to the hitherto unknown part of the EOF value. The majority of the detected fluorinated compounds are legacy PFAS such as short- and long-chain perfluorocarboxylic acids (PFCA), perfluorosulfonic acids (PFSA), polyfluoroalkyl phosphate esters (PAPs) and perfluorophosphonic acids (PFPA). Moreover, fluorinated pesticides, pharmaceutical as well as aromatic compounds were also identified, which are all included in the EOF parameter. Our research revealed that the current PFAS limit of 100 µg/kg for the sum of PFOS + PFOA in the German Fertilizer Ordinance is no longer up to date. Since the number of known PFAS already exceeds 10,000, the ordinance limit should be updated accordingly. Recent regulations and restrictions on using long-chain PFAS (≥C8) have resulted in a significant shift in the industry towards (ultra-)short-chain alternatives, and other, partly unknown, emerging PFAS. Ultimately, also fluorinated pesticides and pharmaceuticals, which end up as ultrashort PFAS in the WWTPs, have to be considered as possible pollutants in fertilizers from wastewater, too.
Over the past century, a range of synthetic compounds have been produced to improve humanity’s quality of life. These include pharmaceuticals, plastics, and other chemical compounds that possess properties making them potentially harmful when released to the environment (e.g., ecological and health impacts to humans and animals). Per- and polyfluoroalkyl substances (PFAS) are a large group of chemicals used in the formulations of thousands of consumer goods, including aqueous film-forming foams used to suppress aviation fires in training scenarios, non-stick cookware, fast-food wrappers, water-repellent fabrics, medical equipment, and plastic and leather products. Because of the recent regulations and restrictions on the use of long chain (≥C8) PFAS a significant shift in the industry towards short (C4-C7) and ultrashort (C1-C3) chain alternatives has been recognized the last years. Due to the high polarity and water solubility of ultrashort PFAS, the potential for bioaccumulation is low. However, the high persistence of ultrashort-chain PFAS will result in environmental accumulation, especially in aquatic environments, leading to potential risks for aquatic organisms and increased human external exposure through drinking water. Ultrashort PFAS like trifluoroacetic acid (TFA) are low to moderately toxic to a range of organisms. In addition, ultrashort PFAS can penetrate natural and anthropogenic barriers and eventually reach drinking water sources. Because common drinking water treatment techniques do not sufficiently remove them, they may reach human consumption. In the project we are focusing on detecting and removing PFAS, especially ultrashort-chain PFAS from contaminated groundwater. We are designing passive sampling devices, which can collect and monitor the temporal profile of PFAS species in groundwater. This will allow us to analyze PFAS contaminations in German and Israeli groundwater using state-of-the-art and novel analytical techniques and understand the extent of contamination. In addition to quantification, PFAS contaminated groundwater will be treated via a two-stage process to produce PFAS-free drinking water. As ultrashort-chain PFAS are difficult to analyze with the current target (LC-MS/MS) and sum parameter (AOF, EOF) analysis methods, we additionally using gas chromatography – mass spectrometry (GC-MS). Therefore, an analytical method based on GC-MS is in development to analyze the volatile ultrashort-chain PFAS (TFA, PFPrA, TFMS, PFEtS, PFPrS, trifluoroethanol, pentafluoropropanol and hexafluoro isopropanol) directly in contaminated groundwater samples with the headspace technique and in eluates of organic solvents from the developed passive sampler after direct injection. Moreover, a two-stages process is designed to increase the low concentrations found in groundwater using novel membranes processes such as closed-circuit reverse osmosis (CCRO) and mixed matrix composite nanofiltration membranes (MMCM). Next, the rejected streams containing higher concentrations of PFAS will be treated by coagulation, and the remaining PFAS adsorbed onto carbonaceous nanomaterials (CNMs). The DEFEAT-PFAS project will result in the development of novel tools to detect, quantify, and remove PFAS, especially ultrashort-chain PFAS from contaminated groundwater, and will acquire a new understanding of the extent of these contaminations.
Half of global material consumption involves mineral material. The circularity is still low so that the enhanced use of secondary building material is required to close loops. Three different secondary building materials are discussed based on exemplary research results: construction and demolition waste (C&D waste), soil-like material, and incineration bottom ash (IBA). Focus was placed on the environmental compatibility of the materials examined mainly by standardized leaching tests. C&D waste was investigated after a wet treatment using a jigging machine, and soil-like material and IBA were characterized with respect to their material composition. Their environmental compatibilities in particular were studied using standard leaching tests (batch tests and column tests).
It was concluded that soil-like material can mostly be utilized even when the precautionary limit values set are exceeded by a factor of less than two. For C&D waste, the fine fraction below 2 mm and the content of brick material is problematic. IBA fulfills quality level “HMVA-2” following German regulations. Improved levels of utilization might be achievable with better treatment technologies.
The release of hazardous compounds from construction products can harm human health and the environment. To improve the sustainability of construction materials, the leaching of substances from construction products and their potential environmental impact should be assessed. Twenty-seven construction products from different product groups were examined with a combination of standardized leaching tests (dynamic surface leaching test and percolation test) and biotests (algae, daphnia, fish egg, luminescent bacteria, umu and Ames fluctuation tests). To identify the released substances, extensive qualitative and quantitative chemical analyses were performed, including gas chromatographic and liquid chromatographic screening techniques.
Results: Many of the tested eluates caused signifcant ecotoxic efects. Particularly high ecotoxicities were observed for grouts (lowest ineffective dilution (LID) up to 16384) and cork granules (LID up to 24578). The results of ecotoxicity tests allow the prioritization of the eluates that should be subjected to detailed chemical analyses. Organic screening by different methods and ranking the identifed substances based on recorded hazard classification is a suitable approach to identify the relevant toxic substances.
Conclusions: Determining the ecotoxicity of eluates from construction products records the summary effect of all leachable substances. This instrument is especially useful for construction products of complex and largely unknown composition. The ecotoxicological and the chemical–analytical approach complement each other in an ideal way to characterize the potential hazard of eluates from construction products and to identify the environmentally hazardous components in these eluates. Our results confirm that the proposed harmonized methods for testing eluate toxicity are an adequate and applicable procedure to move toward a more sustainable way of building and to reduce toxic effects of construction products in their use phase in the environment.
Besides classical per- and polyfluorinated alkylated substances (PFAS), side-chain fluorinated polymers (SFPs) are widely applied as efficient anti-wetting and anti-greasing coatings in various daily applicated consumer products such as outdoor apparel, carpetry or paper-based food contact materials. Although the fluorinated sidechains are chemically bound to a base polymer, their release can be triggered by environmental influences or wear-off, thus contribute as significant sources of PFAS in the environment. Since only little knowledge of PFAS and SFP composition in consumer products is available, a comprehensive analytical approach might be beneficial.
Per- and polyfluoroalkyl substances (PFAS) are a group of anionic, cationic and zwitterionic synthetic products, in which the hydrogen atoms on the carbon skeleton of at least one carbon atom have been completely replaced by fluorine atoms and which include more than 4730 compounds, depending on the definition. As a result of continuous and prolific use, mainly in aviation firefighting foams, thousands of industrial and military installations have been found to contain contaminated soil, groundwater and surface water. Furthermore, current decontamination strategies of PFAS-burdened soils mainly consist of adsorption methods using adsorbents for fixation of PFAS in the ground. Hence, there is a great demand for innovative developments and chemical treatment technologies, dealing with new strategies of tackling the PFAS problem. Thus, we investigated mechanochemical treatment of PFAS contaminated soils with various additives in a ball mill and analyzed the PFAS defluorination. In this presentation the advantages of fluorine K-edge X-ray absorption near-edge structure (XANES) spectroscopy for various environment samples are shown.
In Deutschland fallen aktuell pro Jahr über 5 Mio. Tonnen Hausmüllverbrennungs-aschen (HMVA) an. Eine Verwertung dieser Aschen und Schlacken ist in Deutschland möglich und findet überwiegend im Deponiebau statt. Für die Verwertung sind in der Ersatzbaustoffverordnung Eluatgrenzwerte für Schwermetalle und einige andere Parameter vorgesehen.
Der Umgang mit HMVA könnte durch eine Einstufung als gefährlicher Abfall erschwert werden. Maßgeblich für die Einstufung eines Abfalls als gefährlich oder ungefährlich sind die gefahrenrelevanten Eigenschaften HP 1 bis HP 15 nach Anhang III der Richtlinie 2008/98/EG über Abfälle mit dort festgelegten Konzentrationsgrenzen. Für HMVA ist im Wesentlichen nur der Parameter HP 14 (Ökotoxizität) von Bedeutung. Dafür sind entscheidend die Gehalte an chemischen Verbindungen mit den Gefahrenhinweiscodes (hazard statement code, HSC) H400, H410, H411, H412 und H413. Eine detaillierte Diskussion zu den übrigen Gefahreneigenschaften bei HMVA findet sich in der Literatur. Die Einstufung als gefährlicher Abfall erfolgt nach festgelegten Rechenregeln.
Die BAM bearbeitet ein durch das UBA gefördertes Forschungsprojekt zur Erfassung und Bewertung von Analysedaten zu Aschen und Schlacken aus Abfallverbrennungsanlagen. Die Ergebnisse des Vorhabens sollen bei der Weiterentwicklung des vorhandenen Konzeptes für eine bundeseinheitlichen Untersuchung und abfallrechtlichen Einordnung von Aschen und Schlacken aus deutschen Abfallverbrennungsanlagen unterstützend herangezogen werden. Im Vortrag werden Verfahren zur quantitativen Bestimmung der einstufungsrelevanten Verbindungen vorgestellt: 1.) der Praxisleitfaden von ITAD und IGAM, 2.) Methode basierend auf der Bioverfügbarkeit und 3.) Methode basierend auf Speziierungsanalyse.
Kunststoffdichtungsbahnen (KDB) aus PE-HD (Polyethylen hoher Dichte) werden häufig zur Abdichtung von Bauwerken in der Geotechnik verwendet. Diese Produkte werden aus einem Kunststoff mit relativ komplexer Zusammensetzung hergestellt. Um eine Aussage über die Haltbarkeit von KDB aus PE-HD treffen zu können, muss das Materialverhalten berücksichtigt werden. In diesem Zusammenhang sind die wichtigsten Aspekte der Dauerhaftigkeit die Spannungsrissbeständigkeit und die Beständigkeit gegen Oxidation. Verschiedene PE-Sorten weisen eine unterschiedliche Spannungsrissbeständigkeit auf. Um dieser Eigenschaft von PE-HD zu begegnen, werden nur KDB aus sehr hochwertigen Rohstoffen zugelassen. Auf der anderen Seite werden hohe Anforderungen an die umgebenden Schichten, wie Auflager und Schutzschicht gestellt, um möglichst geringe Spannungen zu erzeugen und damit Dehnungen die Dehnungen der KDB gering zu halten. Bestimmte Medien, die bei den betreffenden Prüfungen verwendet werden, dürfen nicht mehr in der EU in Verkehr gebracht werden. Im Folgenden sollen die Zusammenhänge in Kürze dargestellt werden. Darüber hinaus sollen Diskussionen und Änderungen der Zulassungsrichtlinie für Schutzschichten im und durch den Fachbeirat vorgestellt werden.
Kunststoffdichtungsbahnen (KDB) aus PE-HD (Polyethylen hoher Dichte) werden häufig zur Abdichtung von Bauwerken in der Geotechnik verwendet. Diese Produkte werden aus einem Kunststoff mit relativ komplexer Zusammensetzung hergestellt. Um eine Aussage über die Haltbarkeit von KDB aus PE-HD treffen zu können, muss das Materialverhalten berücksichtigt werden. In diesem Zusammenhang sind die wichtigsten Aspekte der Dauerhaftigkeit die Spannungsrissbeständigkeit und die Beständigkeit gegen Oxidation. Verschiedene PE-Sorten weisen eine unterschiedliche Spannungsrissbeständigkeit auf. Um dieser Eigenschaft von PE-HD zu begegnen, werden nur KDB aus sehr hochwertigen Rohstoffen zugelassen. Auf der anderen Seite werden hohe Anforderungen an die umgebenden Schichten, wie Auflager und Schutzschicht gestellt, um möglichst geringe Spannungen zu erzeugen und damit Dehnungen die Dehnungen der KDB gering zu halten. Bestimmte Medien, die bei den betreffenden Prüfungen verwendet werden, dürfen nicht mehr in der EU in Verkehr gebracht werden. Im Folgenden sollen die Zusammenhänge in Kürze dargestellt werden. Darüber hinaus sollen Diskussionen und Änderungen der Zulassungsrichtlinie für Schutzschichten im und durch den Fachbeirat vorgestellt werden.
Sustainability has become the conscientious and future-oriented principle of modern resource management and environmental protection because caring for the future is tantamount to providing manageable and healthy surroundings for ourselves. For the foreseeable future, geotechnical and environmental engineers must therefore be concerned with ensuring a healthy balance between extraction, processing, manufacturing, utilization, recycling, and disposal of materials and products.
Half of the global material consumption is mineral material. The circularity is still low so that enhanced use of secondary building material is required to close loops. Three different secondary building materials are discussed based on exemplary research results: construction and demolition waste (C&D waste), soil-like material and incineration bottom ash (IBA). Focus was laid on the environmental compatibility of the materials examined mainly by standardized leaching tests. C&D waste was investigated after a wet treatment using a jigging machine, soil-like material and IBA were characterized with respect to their material composition. The environmental compatibility in particular was studied using standard leaching tests (batch tests and column tests). It was concluded that soil-like material can mostly be utilized even when the precautionary limit values set are exceeded by a factor of less than 2. For C&D waste the fine fraction below 2 mm and the content of brick material is problematic. IBA fulfills quality level HMVA-2 following German regulation. Higher quality levels of utilization might be achievable with better treatment technologies.
Thermal Destruction of PFAS
(2023)
Thermal treatment processes are currently the only full-scale option for thedestruction of per- and polyfluoroalkyl substances (PFAS) in large waste streams. While all organic molecules including PFAS are susceptible to thermal destruction, their decomposition rates are controlled by process variables such as temperature, reaction atmosphere, and residence time. Concerns exist about the formation of products of incomplete destruction and their emission from hazardous waste incinerators. This talk will summarize the current stateof-the-art of thermal PFAS destruction, identify research needs, and showcase future research designed to address critical knowledge gaps.
The long-term leaching behavior of incineration bottom ash (IBA) was studied with large-scale samples from two German waste incinerators with grate technology. The observation period was up to 281 days. The aging processes proceeded faster in the outdoor storage of the samples. The dominant factor in the leaching behavior is the pH, which starts at values above 12 and decreases to values below 10 (outdoors, <11 indoors). Most heavy metals exhibit minimum solubility in this pH range. The solubility of Sb depends on the prevailing Ca concentration, due to the formation of low-soluble Ca antimonate. The very low sulfate concentrations observed in the leaching tests with fresh IBA could be explained by the presence of ettringite. In the course of the aging reaction, ettringite is transformed into gypsum. The results from batch tests were compared with those from column tests, showing reasonable agreement. Leaching dynamics can be better followed with column tests. All results confirm that the use of IBA is possible under German law.
Wet-mechanical treatment: Processing of bituminous road construction waste in a jigging machine
(2023)
Jigging machines are used in processing technology in many areas. Examples are the processing of coal, ores, and primary and secondary raw and waste materials. Even small differences in density are offen sufficient for successful sorting. In the work presented here, milled material from road construction waste contaminated with bitumen is to be separated from uncontaminated material. In this way, scarce landfill space could be saved and mineral material be returned to the material cycle.
Current decontamination strategies of PFAS-burdened soils mainly consist of adsorption methods using adsorbents for fixation of PFAS in the ground. A second option is the utilization of a “pump and treat” process, cycling polluted soils through a washing plant leading to the concentration of the pollutants in the fine fraction. Only a subsequent, high-energy consuming pyrolysis process guarantees the total destruction of all fluorinated organic contaminants. These approaches are cost-intensive and not intended for the direct decomposition of all PFAS contaminants. Hence, there is a great demand for innovative developments and chemical treatment technologies, dealing with new strategies of tackling the PFAS problem. Thus, we investigated mechanochemical treatment of PFAS contaminated soils with various additives in a ball mill and analyzed the PFAS defluorination with gas chromatography mass spectrometry (GC-MS) and liquid chromatography tandem mass spectrometry (LC-MS/MS), respectively, as well as the fluoride mineralization by ion chromatography (IC) and fluorine K-edge X-ray absorption near-edge structure (XANES) spectroscopy.
Aim. The European biocidal products regulation requires environmental risk assessments for biocidal products under service conditions. This is only possible, if processes that lead to biocide emissions into the environment are understood and can be reasonably predicted.
Actual emissions due to leaching result from different processes that are affected by material properties and environmental conditions. Transformation of biocides can affect emissions considerably.
Leaching and possible transformation of the film preservatives carbendazim, diuron, OIT and terbutryn in paints was observed under laboratory and field conditons in order to investigate the influence of different factors, e.g. water contact and radiation on biocide emissions. The paints contained either white titanium dioxide or a red iron oxide pigment to check whether pigments affect leaching processes.
Methods. Test specimens of a water-based styrene acrylic dispersion paint on glass were exposed to UVA-radiation in a UV weathering device and/or exposed to water contact by immersion events on the basis of the European standard EN 16105. Plywood panels were coated and exposed to natural weather conditions in a semi-field experiment. Concentrations of biocides and transformation products were analysed in leachates from laboratory tests, runoff samples and remaining coatings.
Results. The impact of weathering conditions on transformation processes differs for the investigated active substances. Water contact, radiation as well as pigments in the paints determine the pattern and amount of transformation products on coatings, leachates and runoff water. Observations from laboratory and field experiments were compared. It proved that results from laboratory tests support understanding of data from field experiments.
Detailed knowledge on the fate of active substances under environmental conditions supports manufacturers to develop safe applications of film preservatives and authorities to evaluate its environmental impact.
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.
Per- and polyfluoroalkyl substances (PFAS) are a large group of organofluorine surfactants used in the formulations of thousands of consumer goods, including aqueous film-forming foams (AFFF) used to suppress aviation fires in training scenarios, non-stick cookware, fast-food wrappers, water-repellent fabrics, medical equipment, and plastic and leather products. As a result of the perpetual use of PFAS containing products, effluents and sewage sludge from wastewater treatment plants (WWTPs) have been observed to be an important pathway for PFAS into the environment. In Germany, phosphorus and other nutrients from sewage sludge and wastewater should be recycled in WWTPs of cities with a large population. However, it is not clear if PFAS contamination from wastewater and sewage sludge end up in novel wastewater-based fertilizers. Normally, PFAS are analyzed using PFAS protocols typically with time-consuming extraction steps and LC-MS-MS quantification. However, for screening of PFAS contaminations in sewage sludge or wastewater-based fertilizers also passive sampler based on the Diffusive Gradients in Thin-films (DGT) technique can be used for the PFAS extraction. Afterwards, combustion ion chromatography (CIC) can be applied to analyse the “total” amount of PFAS on the passive sampler. Here, we show results from the DGT method in comparison to those of the extractable organic fluorine (EOF) method for a variety of wastewater-based fertilizers. Additionally, we analysed the adsorption of PFAS on the weak anion exchanger (WAX) based DGT passive sampler binding layer by infrared and fluorine K-edge X-ray adsorption near-edge structure (XANES) spectroscopy.
Per- and polyfluoroalkyl substances (PFAS) have emerged over the course of the last twenty years as a global pollution issue. Altogether, there are currently more than 4700 known but only partly characterized fluorinated compounds identified by the Organization for Economic Cooperation and Development (OECD), as shown by a recently published classification proposal.
The ongoing production of new, yet unrestricted PFAS alternatives has become a major challenge for environmental routine analytics, since the state-of-the-art method LC-MS/MS relies on structural information and availability of isotope standards of the targeted compound. First reported by Miyake et al., fluorine sum parameters like adsorbable organic fluorine (AOF), extractable organic fluorine (EOF) and total fluorine (TF) can be applied to survey and detect the presence of large amounts of unidentified organofluorine compounds in environmental matrices. Today fluorine sum parameters have been established as a useful supplement to classic target-analytical approaches of PFAS and were implemented for the first time as a sum value “PFAS-total” in the recently revised Drinking Water Directive (2020/2184) by the European Commission.
In contrast, X-ray absorption near-edge structure (XANES) spectroscopy has been widely applied to identify low concentration of element-specific contamination without pre-treatment in environmental samples in the past. The XANES approach enables a penetration depth of approx. 1 µm (at fluorine K-edge energy; depending on the matrix) which is significantly deeper than for X-ray photoelectron spectroscopy (XPS; penetration depth approx. 10 nm). Furthermore, the method is fast, non-destructive and only simple preparation of the samples is required.
In our work, we combined both F-XANES spectroscopy and combustion ion chromatography (CIC) in order to present a new analytical perspective on the investigation of PFAS in environmental media and material samples.
Release of substances from joint grouts based on various binder types and their ecotoxic effects
(2022)
Background: The leaching of substances and the ecotoxic effects of eluates were studied for joint grouts that are based on various types of binders. Eight products, two of them containing either epoxy resin, polybutadiene or polyurethane binders, or modifed cement, were investigated using harmonized leaching tests for construction products in combination with ecotoxicity tests on algae, daphnia, luminescent bacteria, fish eggs and mutagenicity in accordance with CEN/TR 17105. In addition to basic parameters, such as pH, TOC, and inorganic components, organic substances in the eluates were analysed by gas and liquid chromatography in combination with mass spectrometry. Quantitative analyses in combination with ecotoxicity data on selected substances were used to deduce which substances cause the observed ecotoxic effects.
Results: Different patterns of ecotoxic effects were observed in joint grouts with different binder types. The most ecotoxic effects were observed in epoxy resin-based products, followed by polybutadiene-based products. Fewer ecotoxic effects were observed in polyurethane-based products and modifed cements. Some of these showed no ecotoxicity. Some of the substances in the eluates were identified and related to ecotoxic effects. 4-Tert-butylphenol and amines probably contributed to the ecotoxic effects of at least one of the epoxy resin-based renders, whereas cobalt is assumed to contribute to the toxic effect on algae of one of the polybutadiene-based products. However, only some of the leached substances could be identifed, and only some of the ecotoxic effects can be explained by the available information on the composition of eluates and known ecotoxic profiles of the identified substances.
Conclusions: Ecotoxicity tests on eluates from leaching tests indicate whether environmentally hazardous substances can be leached from construction products. Combined ecotoxicity tests and chemical analysis of eluates from EU-wide harmonized leaching tests for construction products can provide information on substances that cause these effects. This supports the identifcation and development of environmentally friendly construction products.
This study confirmed that ecotoxicity tests in accordance with CEN/TR 17105 are a tool well-suited to support the implementation of the European Commission’s zero pollution vision for 2050 and to reduce pollution to levels no longer considered harmful to health and natural ecosystems.
Der Fachbeirat kommt bereits seit 13 Jahren in seiner jetzigen Form zusammen, um Zulassungsrichtlinien, weitere Dokumente und fachliche Fragestellungen zu beraten. Die Zeit bringt auch personelle Veränderungen mit sich, darüber wollen wir berichten. Derzeit wird die Zulassungsrichtlinie für Schutzschichten im Fachbeirat und in seiner Arbeitsgruppe Geotextilien und Kunststoff Dränelemente (AG Geotextilien) überarbeitet. Zudem wurde die Zulassungsrichtlinie für Kunststoffdichtungsbahnen auf den aktuellen Stand der Regelsetzung und Normung gebracht. Bestimmte Medien, die hier bei einigen Prüfungen verwendet werden, dürfen nicht mehr in der EU in Verkehr gebracht werden. Hier werden die Hintergründe und Zusammenhänge in Kürze aufgezeigt. Zuletzt wird die Diskussion in Bezug auf den Einsatz von Rezyklaten in den zugelassenen Produkten aufgeführt.