Suchergebnisse

Heavy metals, even being natural componets of the environment, are toxic to organisms surpassing specific thresholds. The organisms have adapted to the native occurence and bioavailablity of heavy metals depending on the actual situation (pH, organic content, …) by their choose of habitat. However, by anthropogenic activity the heavy metals are carried in the atmosphere over large distances and are accumulated after deposition in habitats like topsoil. If the bioavailable concentrations surpass specific threshold values, a harm on humans and environment cannot be excluded. Due to this, the release of heavy metals into the environment is regulated by law. To determine hazard-free heavy metal depositions, ecological threshold values – so called Critical Loads – are calculated for heavy metals. Critical Loads base on so called Critical Limits. These are concentrations in environmental matrices, which should not be exceeded in order to avoid harmful effects. In the scope of this project, a worldwide literature research should identify and list all relevant studies since 2005, dealing with chronic effects of increased heavy metal concentrations on terrestric organisms and ecosystem functions to find recent data to be used for a review of the Critical Limits calculation. It is not the goal of this project to discuss or evaluate the relevant data. All relevant data is submitted as a literature data base and an Excel data compilation including all relevant information necessary for calculation of Critical Limits to the German Environment Agency. Additionally, this summary report is prepared. The report lists the relevant references with effect concentrations, endpoints (e.g. reproduction), organism group and species, as well as soil parameters in tables and gives a short summary, separated for all heavy metals found in the literature reseach applied.

In the recent study, two endocrine active substances for human use, the progestin Dienogest and the glucocorticoid Dexamethasone, were tested in a 28-day reproduction test with the New Zealand mud snail Potamopyrgus antipodarum according to the OECD guideline 242. In a ring test in 2016, in which the Fraunhofer IME successfully participated, the OECD test guideline 242 was validated in order to broaden the range of test methods for investigations of e.g. endocrine active substances and their endocrine and reproductive toxic effects on aquatic invertebrates, particularly on water snails as they are proved to be sensitive towards endocrine disruptors (EDs). Until then the focus in testing of EDs was mainly on studies with fish. The results of this study will be used to establish a tailored evaluation concept for environmental risks for progestins and artificial glucocorticoids. In the reproduction test with Dienogest analytically verified concentrations of 6.97, 11.2, 25.6, 106 and 332 ng/L were introduced. After 28 days, no significant effect on any of the investigated endpoints was observed. The NOEC for reproduction (in terms of total, shelled and unshelled embryos), survival and length were therefore determined to be ≥ 332 ng/L, respectively. The reproduction test with Dexamethasone was performed with analytically verified concentrations of 1.06, 3.54, 10.5, 36.3 and 105 μg/L. After 28 days, no significant effect on reproduction, survival and length occurred, resulting in a NOEC of ≥ 105 μg/L, respectively.

Im Rahmen dieses Forschungsvorhabens wurden Untersuchungen durchgeführt, um Grundlagen für ein geeignetes Konzept zur Überwachung von prioritären Stoffen in Fischen zu erarbeiten, das den Anforderungen der Wasserrahmenrichtlinie (WRRL) genügt und dabei die verschiedenen Ziele des Gewässermonitorings, insbesondere die Überwachung von Umweltqualitätsnormen (UQN) sowie das Trendmonitoring, integriert. Dazu wurden an sechs Standorten in Oberflächengewässern jeweils ca. 20 Fische von jeweils drei unterschiedlichen Fischspezies beprobt, biometrische Daten erfasst (z.B. Gewicht, Länge, Alter) und Mischproben von Filet und Restfisch getrennt auf prioritäre Stoffe untersucht. Aus den Messdaten wurden die Konzentrationen der prioritären Stoffe im Ganzfisch berechnet. Bei der Projektbearbeitung wurden die Hinweise des Arbeitspapiers IV.3 zur Rahmenkonzeption Monitoring (RAKON) der LAWA (Bund/Länder-Arbeitsgemeinschaft Wasser) berücksichtigt und geprüft, inwieweit das empfohlene Vorgehen an den Standorten umsetzbar war. Auf Basis der Untersuchungsergebnisse wurden Empfehlungen für die Umsetzung des WRRL-Biotamonitorings abgeleitet. Da das Routine-Gewässermonitoring Aufgabe der Bundesländer ist, wurden Aspekte der praktischen Umsetzung mit den zuständigen Kolleginnen und Kollegen aus Einrichtungen der Bundesländer im Rahmen von zwei Fachgesprächen diskutiert.