Person:
Schmidt, Ralf

Profilbild
E-Mail-Adresse
Geburtsdatum
Forschungsvorhaben
Organisationseinheiten
Logo der Organisationseinheit
Organisationseinheit
Berufsbeschreibung
Nachname
Schmidt
Vorname
Ralf
Name

Filter

2018 - 201912020 - 20211
Filter zurücksetzen

Einstellungen

Autor:in: Schmidt, Ralf ×

Suchergebnisse

Gerade angezeigt 1 - 2 von 2
  • Vorschaubild nicht verfügbar
    Veröffentlichung
    Fate, bioaccumulation and toxic effects of triclosan on a freshwater community - a mesocosm study
    (2021) Berghahn, Rüdiger; Contardo-Jara, Valeska; Feibicke, Michael; Meinecke, Stefan; Mohr, Silvia; Schmidt, Ralf
    The antibacterial agent triclosan (TCS) is added to many daily-used consumer products and can therefore reach the aquatic environment via treated wastewater and potentially harm aquatic ecosystems. A 120 days pond mesocosm study was conducted in order to investigate the fate of TCS in water and sediment, its bioaccumulative potential in different biota as well as the effects of TCS and its main transformation product methyl-triclosan (M-TCS) on plankton, periphyton, macrophytes, and benthos communities. TCS was dosed once each in six pond mesocosms (nominal concentrations: 0.12, 0.6, 3.5, 21, 130 and 778 (micro)g/L TCS, respectively) while two ponds served as controls. A concentration-dependent increase in the DT50 values from 5.0 to 15.0 and 7.5 to 16.3 days was observed for TCS in water and the whole pond system (water, sediment, biota), respectively. Consequently, the substance should be categorized as non-persistent. For TCS, the bioaccumulation factors (non steady-state conditions, BAFnssc) in Lymnaea stagnalis, Myriophyllum spicatum and periphyton were below the critical limit of 2000, above which a substance is classified as bioaccumulative. In contrast, a BAFnssc value of >10,000 was found for M-TCS in L. stagnalis, denoting that M-TCS definitely falls under this classification. Although strong effects on freshwater communities could only be observed in the highest TCS treatments, some periphyton species, such as Oedogonium spp., reacted very sensitive to TCS with an EC50 (time weighted average, 28 d) of 0.3 (micro)g/L TCS. Considering the high bioaccumulative potential of M-TCS in combination with the observed effects of TCS at low doses suggests that the use of TCS, and therefore its release into the environment, should cease. © 2021 The Authors
  • Vorschaubild
    Veröffentlichung
    Sind kupferhaltige Antifouling-Anstriche ein Problem für unsere Gewässer?
    (2018) Ahting, Maren; Feibicke, Michael; Nöh, Ingrid; Rissel, Ricarda; Schmidt, Ralf; Schwanemann, Torsten; Setzer, Sascha
    Sportboote tragen mit Antifouling-Anstrichen des Unterwasserrumpfes zu Chemikalieneinträgen in Gewässer bei. Erstmals konnten die Einträge von Kupfer und anderen Bioziden aus dieser Quelle abgeschätzt werden: Jährlich gelangen 70.5 t Kupfer, 20 t Zink und 9.5 t organische Biozide in deutsche Binnengewässer. Damit konnten 19 % der Kupfereinträge auf diese Anwendung zurückgeführt werden. Da Grenzwerte für Kupfer immer wieder überschritten werden, sollten Maßnahmen ergriffen werden, um die Einträge zu reduzieren und die Gewässer zu schützen. Quelle: https://www.umweltbundesamt.de