Suchergebnisse

Trophic magnification factors (TMFs) have been derived in a variety of different aquatic eco-systems worldwide to investigate accumulation patterns of environmentally relevant chemicals. The TMF is defined as a metric that describes the average trophic magnification of a chemical through the analyzed food web under realistic environmental conditions. Not only is the TMF interesting for chemicals' risk assessment related questions, but also for monitoring aspects under the European Water Framework Directive (WFD). This study is the first TMF study con-ducted in a German freshwater ecosystem, that is, Lake Templin near Potsdam. Aim of the study was to investigate the food web magnification following existing guidance to derive reliable TMFs that could be used for regulatory purposes. A sampling campaign yielded 15 biota samples covering about three trophic levels, which have been processed and cryo-preserved following standardized protocols of the German Environmental Specimen Bank (ESB). The samples remain available for future analysis and, thus, form a "food web on ice". These large-scale food web samples are ready-to-use for a broad variety of analyses. In a first step, a plausibility check was performed. Different persistent organic pollutants (POPs), which are known to magnify in food webs and are not readily metabolized, serve as benchmarks. It could be shown that for nearly all of the POPs analyzed, the TMFs are significantly above 1. In a few cases, an enrichment is also seen, but not statistically relevant. Since not only POPs with lipophilic accumulation properties were analyzed, it could be concluded that the food web on ice samples from Lake Templin can be used to characterize the trophic magnification potential of further substances with less investigated bioaccumulation properties present in the samples. To this end, several PFAS, pharmaceuticals, pesticides and methyl siloxanes were investigated in the samples to derive their TMFs.

Die Umweltprobenbank des Bundes (UPB) ist ein Archiv. Proben des Menschen und der Umwelt lagern dort bei sehr tiefen Temperaturen. Mit den regelmäßig gesammelten Proben können wir den Zustand unserer Umwelt dokumentieren und beobachten, wie sich die Belastung durch natürliche und anthropogene (Schad)Stoffe mit der Zeit verändert. Die Proben der UPB werden so gewonnen, transportiert, aufgearbeitet und gelagert, dass ihre biologische und chemische Information auch über lange Zeiträume konstant bleibt. Auf diese Weise machen es Umweltprobenbanken möglich, dass wir aktuelle Proben mit Archivmaterial vergleichen können, das vor Jahrzehnten gesammelt und eingelagert wurde.

Schwebstoff- und Sedimentproben aus deutschen Fließgewässern und Seen wurden auf ihre Belastung mit Per- und polyfluorierten Alkylsubstanzen (PFAS) untersucht. Die flächenhafte Verteilung der PFAS-Belastung wurde mit Hilfe von behördlichen Monitoringproben aus 2021 untersucht. Diese aktuellen Daten wurden flankiert von zeitlichen Trenduntersuchungen, die sich auf Proben der Umweltprobenbank von 13 Standorten in Donau, Rhein, Saar, Elbe, Mulde, Saale aus den Jahren 2005 – 2019 stützten. Die Ergebnisse sind in einem öffentlich zugänglichen Onlinetool verfügbar und in wissenschaftlichen Publikationen veröffentlicht. Für das Flächenmonitoring wurden insgesamt 214 Schwebstoff- und Sedimentproben von 176 verschiedenen Probenahmeflächen (davon 5 in den Niederlanden) untersucht, während sich das Trendmonitoring auf 100 Schwebstoff-Proben von der Umweltprobenbank stützte. Alle Proben wurden mittels Einzelstoffanalytik (Targetanalytik) auf 41 verschiedene PFAS-Verbindungen untersucht. Zusätzlich kam eine summarische Methode zum Einsatz (direct Total Oxidizable Precursor (dTOP) -Assay), die auf den TOP-Assay von Houtz und Sedlak (2012) zurückgeht und die Gesamtbelastung der Proben mit PFAS deutlich umfassender beschreibt. Die mit dem dTOP-Assay ermittelten PFAS-Gesamtkonzentrationen waren bis zu 346-mal höher als die mit der Einzelstoffanalytik gemessenen Werte. Dies deutet auf erhebliche Mengen an unbekannten Vorläuferverbindungen in den Proben hin. Die Gesamt-PFAS-Belastungen innerhalb Deutschlands unterschieden sich stark und schwankten in 2021 zwischen <0,5 und 53.1 μg/kg Trockengewicht (TG) in der Targetanalytik und zwischen <1,0 und 336,8 μg/kg TG im dTOP-Assay. Die höchsten Belastungen fanden sich meist flussabwärts von großen Kläranlagen und PFAS-produzierenden oder verarbeitenden Industrien. Das zeitlich Trendmonitoring zeigte, dass die PFAS-Belastung von Schwebstoffen in deutschen Fließgewässern zwischen 2005 und 2019 abgenommen hat. Dies ist im Wesentlichen auf den Rückgang langkettiger Verbindungen zurückzuführen, von denen einige bereits reguliert werden. Der proportionale Anteil unbekannter Vorläufersubstanzen nahm jedoch zu. Die Ergebnisse belegen, dass die Targetanalytik nur einen Bruchteil der tatsächlichen PFAS-Belastung erfasst. Unbekannte Vorläuferverbindungen und möglicherweise auch nicht-extrahierbare PFAS bleiben unerkannt. Dies führt zu ungenauen Trendanalysen und verfälscht räumliche Belastungsmuster. Bei der Bewertung des Umweltrisikos und der gesetzlichen Regulierung sollte daher eine breitere Palette von PFAS berücksichtigt werden, wobei summarische Methoden wie der dTOP-Assay einen wichtigen Beitrag leisten können.

AbstractA 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 'real world' 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.

AbstractMonitoring 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.

Water is a vital resource for natural ecosystems and human life, and assuring a high quality of water and protecting it from chemical contamination is a major societal goal in the European Union. The Water Framework Directive (WFD) and its daughter directives are the major body of legislation for the protection and sustainable use of European freshwater resources. The practical implementation of the WFD with regard to chemical pollution has faced some challenges. In support of the upcoming WFD review in 2019 the research project SOLUTIONS and the European monitoring network NORMAN has analyzed these challenges, evaluated the state-of-the-art of the science and suggested possible solutions. We give 10 recommendations to improve monitoring and to strengthen comprehensive prioritization, to foster consistent assessment and to support solution-oriented management of surface waters. The integration of effect-based tools, the application of passive sampling for bioaccumulative chemicals and an integrated strategy for prioritization of contaminants, accounting for knowledge gaps, are seen as important approaches to advance monitoring. Including all relevant chemical contaminants in more holistic "chemical status" assessment, using effect-based trigger values to address priority mixtures of chemicals, to better consider historical burdens accumulated in sediments and to use models to fill data gaps are recommended for a consistent assessment of contamination. Solution-oriented management should apply a tiered approach in investigative monitoring to identify toxicity drivers, strengthen consistent legislative frameworks and apply solutions-oriented approaches that explore risk reduction scenarios before and along with risk assessment.