Auflistung nach Autor:in "Alygizakis, Nikiforos A."

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Development of an analytical method for the quantification of surfactants and its application to wastewater treatment plant effluents
(2019) Scheurer, Marco; Freeling, Finnian; Alygizakis, Nikiforos A.; Technologiezentrum Wasser (Karlsruhe); Environmental Institute, s.r.o. (Kos); von der Ohe, Peter C.
Zur Bestimmung der Konzentrationen linearer Alkylbenzolsulfonate (LAS) und Alkylethersulfate (AES) in Kläranlagenabläufen wurden 7-Tagesmischproben (n=33) an Abläufe von 33 konventionellen Kläranlagen in Deutschland genommen. Zudem wurden an vier der untersuchten Kläranlagen die Zuläufe beprobt und ebenfalls auf LAS und AES untersucht, um Rückschlüsse auf die Entfernung dieser Tenside in konventionellen Kläranlagen ziehen zu können. Insgesamt umfasste die Studie die Analyse von vier LAS-Homologen (C10-C13) sowie von jeweils 10 Ethoxymeren zweier Homologe von AES (C12 und C14, jeweils mit 0-9 Ethoxygruppen). Die Probenvorbereitung bestand aus der Entfernung der wässrigen Phase mit Hilfe eines Rotations-Vakuum-Konzentrators und anschließender Resolvatisierung des Trockenrückstandes in einer definierten Menge Reinstwasser und Acetonitril. Die Identifikation und Quantifizierung der Zielanalyten erfolgte mittels Hochleistungsflüssigkeitschromatographie mit Tandem-Massenspektrometrie-Kopplung (HPLC-MS/MS). Die Leistungsfähigkeit der analytischen Methoden wurde in Leitungswasser und Kläranlagenablauf evaluiert. Die Analysemethoden zeigten für beide Matrices eine allgemein gute Richtigkeit sowie Präzision. Basierend auf den geschätzten mittleren Konzentrationen einzelner LAS-Homologe wurde eine mittlere Gesamtkonzentration von 14,4 (mikro)g/L in Kläranlagenabläufen ermittelt. Verglichen mit LAS, wurden für AES stets geringere Gesamtkonzentrationen im Ablauf gemessen: Die mittlere AES-Gesamtkonzentration in den Abläufen betrug 0,57 (mikro)g/L. Zwischen den Gesamtkonzentrationen von AES und LAS bestand keine Korrelation. In den Zuläufen beprobter Kläranlagen wurden im Mittel 3.200 (mikro)g/L LAS detektiert. Damit betrug die mittlere Entfernung für LAS 99,6 %. Die mittlere AES-Konzentration im Kläranlagenzulauf belief sich auf 680 (mikro)g/L, was einer mittleren AES-Entfernung von >99.9% entspricht. Retrospektives Screening von 1.564 Tensiden und deren Transformationsprodukte (TPs) erfolgte durch ein zweites Labor unter Anwendung der Ultrahochleistungsflüssigkeitschromatographie mit Flugzeitmassenspektrometer-Kopplung (UHPLC-QTOF-MS). In vielen Fällen wurde die Konzentration von LAS von der Summe der Konzentrationen der Neben- und Transformationsprodukte von LAS überstiegen. Für die LAS-Nebenprodukte Dialkyltetralinsulfonate (DATS) lag die maximale Summenkonzentration bei 19 (mikro)g/L, für die Sulfophenylalkylcarbonsäuren (SPACs) bei 17 (mikro)g/L und für die Sulfotetralinalkylcarbonsäuren (STACs) bei 5,3 (mikro)g/L. Hohe Konzentrationen von bis zu 7,4 (mikro)g/L wurden für Polyethylenoglycole in den Abwasserproben bestimmt. Die Gesamtkonzentration aller quantifizierten Tenside, TPs und Nebenprodukte in einer einzelnen Probe betrug bis zu 82 (mikro)g/L. Quelle: Forschungsbericht
Explaining the rationale behind the risk assessment of surfactants by Freeling et al. (2019)
(2020) Freeling, Finnian; Alygizakis, Nikiforos A.; von der Ohe, Peter C.
Occurrence and potential environmental risk of surfactants and their transformation products discharged by wastewater treatment plants
(2019) Freeling, Finnian; Alygizakis, Nikiforos A.; von der Ohe, Peter C.
Seven-day composite effluent samples from a German monitoring campaign including 33 conventional wastewater treatment plants (WWTP) were analyzed for linear alkylbenzene sulfonates (LAS) and alkyl ethoxysulfates (AES) and were screened by wide-scope suspect screening for 1564 surfactants and their transformation products (TPs) by UHPLC-ESI-QTOF-MS. Corresponding seven-day composite influent samples of selected WWTPs showed high influent concentrations as well as very high removal rates for LAS and AES. However, average total LAS and AES effluent concentrations were still 14.4 ng/L and 0.57 ng/L, respectively. The LAS-byproducts di-alkyl tetralin sulfonates (DATSs), the TPs sulfophenyl alkyl carboxylic acids (SPACs) and sulfo-tetralin alkyl carboxylic acids (STACs) reached maximum effluent concentrations of 19 ng/L, 17 ng/L and 5.3 ng/L, respectively. In many cases the sum of the concentration of all LAS-related byproducts and TPs surpassed the concentration of the precursors. High concentrations of up to 7.4 ng/L were found for 41 polyethylenoglycol homologs. Quantified surfactants and their TPs and by-products together accounted for concentrations up to 82 ng/L in WWTP effluents. To determine the risk of individual surfactants and their mixtures, single homologs were grouped by a "weighted carbon number approach" to derive normalized Predicted No-Effect Concentrations (PNEC), based on experimental ecotoxicity data from existing risk assessments, complemented by suitable Quantitative Structure-Activity Relationships (QSAR) predictions. Predicted Environmental Concentrations (PEC) were derived by dividing effluent concentrations of surfactants by local dilution factors. Risks for all analyzed surfactants were below the commonly accepted PEC/PNEC ratio of 1 for single compounds, while contributions to mixture toxicity effects from background levels of LAS and DATS cannot be excluded. Maximum LAS concentrations exceeded half of its PNEC, which may trigger country-wide screening to investigate potential environmental risks. © 2019 Elsevier B.V. All rights reserved.
The NORMAN Suspect List Exchange (NORMAN-SLE): facilitating European and worldwide collaboration on suspect screening in high resolution mass spectrometry
(2022) Taha, Hiba Mohammed; Aalizadeh, Reza; Alygizakis, Nikiforos A.; Koschorreck, Jan; Meier, Christiane; Neumann, Michael; Schliebner, Ivo; von der Ohe, Peter C.
Background The NORMAN Association (https://www.norman-network.com/) initiated the NORMAN Suspect List Exchange (NORMAN-SLE; https://www.norman-network.com/nds/SLE/) in 2015, following the NORMAN collaborative trial on non-target screening of environmental water samples by mass spectrometry. Since then, this exchange of information on chemicals that are expected to occur in the environment, along with the accompanying expert knowledge and references, has become a valuable knowledge base for "suspect screening" lists. The NORMAN-SLE now serves as a FAIR (Findable, Accessible, Interoperable, Reusable) chemical information resource worldwide. Results The NORMAN-SLE contains 99 separate suspect list collections (as of May 2022) from over 70 contributors around the world, totalling over 100,000 unique substances. The substance classes include per- and polyfluoroalkyl substances (PFAS), pharmaceuticals, pesticides, natural toxins, high production volume substances covered under the European REACH regulation (EC: 1272/2008), priority contaminants of emerging concern (CECs) and regulatory lists from NORMAN partners. Several lists focus on transformation products (TPs) and complex features detected in the environment with various levels of provenance and structural information. Each list is available for separate download. The merged, curated collection is also available as the NORMAN Substance Database (NORMAN SusDat). Both the NORMAN-SLE and NORMAN SusDat are integrated within the NORMAN Database System (NDS). The individual NORMAN-SLE lists receive digital object identifiers (DOIs) and traceable versioning via a Zenodo community (https://zenodo.org/communities/norman-sle), with a total of > 40,000 unique views, > 50,000 unique downloads and 40 citations (May 2022). NORMAN-SLE content is progressively integrated into large open chemical databases such as PubChem (https://pubchem.ncbi.nlm.nih.gov/) and the US EPA's CompTox Chemicals Dashboard (https://comptox.epa.gov/dashboard/), enabling further access to these lists, along with the additional functionality and calculated properties these resources offer. PubChem has also integrated significant annotation content from the NORMAN-SLE, including a classification browser (https://pubchem.ncbi.nlm.nih.gov/classification/#hid=101). Conclusions The NORMAN-SLE offers a specialized service for hosting suspect screening lists of relevance for the environmental community in an open, FAIR manner that allows integration with other major chemical resources. These efforts foster the exchange of information between scientists and regulators, supporting the paradigm shift to the "one substance, one assessment" approach. New submissions are welcome via the contacts provided on the NORMAN-SLE website (https://www.norman-network.com/nds/SLE/). © The Authors 2022
Using environmental monitoring data from apex predators for chemicals management: towards better use of monitoring data from apex predators in support of prioritisation and risk assessment of chemicals in Europe
(2022) Slobodnik, Jaroslav; Badry, Alexander; Alygizakis, Nikiforos A.; Claßen, Daniela; Koschorreck, Jan; Treu, Gabriele
A large number of apex predator samples are available in European research collections, environmental specimen banks and natural history museums that could be used in chemical monitoring and regulation. Apex predators bioaccumulate pollutants and integrate contaminant exposure over large spatial and temporal scales, thus providing key information for risk assessments. Still, present assessment practices under the different European chemical legislations hardly use existing chemical monitoring data from top predators. Reasons include the lack of user-specific guidance and the fragmentation of data across time and space. The European LIFE APEX project used existing sample collections and applied state-of-the-art target and non-target screening methods, resulting in the detection of>4,560 pollutants including legacy compounds. We recommend establishing infrastructures that include apex predators as an early warning system in Europe. Chemical data of apex species from freshwater, marine and terrestrial compartments should become an essential component in future chemical assessment and management across regulations, with the purpose to (1) validate registration data with ââą Ìreal worldââą Ì measurements and evaluate the predictability of current models; (2) identify and prioritise hazardous chemicals for further assessment; (3) use data on food web magnification as one line of evidence to assess biomagnification; (4) determine the presence of (bio)transformations products and typical chemical mixtures, and (5) evaluate the effectiveness of risk management measures by trend analysis. We highlight the achievements of LIFE APEX with regard to novel trend and mixture analysis tools and prioritisation schemes. The proposed advancements complement current premarketing regulatory assessments and will allow the detection of contaminants of emerging concern at an early stage, trigger risk management measures and evaluations of their effects with the ultimate goal to protect humans and the environment. This is the second policy brief of the LIFE APEX project. © The Author(s) 2022
Using environmental monitoring data from apex predators for chemicals management: towards harmonised sampling and processing of archived wildlife samples to increase the regulatory uptake of monitoring data in chemicals management
(2022) Slobodnik, Jaroslav; Badry, Alexander; Alygizakis, Nikiforos A.; Claßen, Daniela; Koschorreck, Jan; Treu, Gabriele
Monitoring data from apex predators were key drivers in the development of early chemicals legislations due to the population declines of many species during the twentieth century, which was linked to certain persistent organic pollutants (POPs). Besides triggering the development of global treaties (e.g. the Stockholm Convention), chemical monitoring data from apex predators have been particularly important for identifying compounds with bioaccumulative properties under field conditions. Many apex predators are protected species and only a few environmental specimen banks (ESBs) regularly collect samples as many ESBs were established during the 1980-1990s when apex predators were scarce. Today, many POPs have been banned, which contributed to the recovery of many apex predator populations. As a consequence, apex predator samples are now available in research collections (RCs) and natural history museums (NHMs). These samples can be used for routine analysis as well as for screening studies using novel analytical techniques and advanced data treatment workflows, such as suspect and non-target screening. The LIFE APEX project has demonstrated how these samples can be used in a cost-efficient way to generate data on legacy compounds and contaminants of emerging concern. Furthermore, it has described quality assurance/control measures to ensure high quality and comparable data, with a view to uses in chemicals risk assessment and management. To increase the visibility of available sample collections and monitoring data from apex predators we developed accessible online database systems. Additionally, the acquired high-resolution mass spectrometric data were stored in a digital sample freezing platform that allows retrospective suspect screening in previously analysed samples for substances that may be of concern/under assessment in the future. These databases provide open access to a wide range of chemical data, for use by regulators, researchers, industry and the general public, and contribute to a stronger link between science and policy. © The Author(s) 2022