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| Titel |
A floodplain mesocosm study: Distribution, mobility, aging, and functioning
of engineered silver nanoparticles at the aquatic-terrestrial interface |
| VerfasserIn |
George Metreveli, Sandra Kurtz, Allan Philippe, Narjes Tayyebi, Frank Seitz, Ricki R. Rosenfeldt, Alexandra Grün, Samuel K. Kumahor, Thomas Baumann, Mirco Bundschuh, Friederike Lang, Sondra Klitzke, Werner Manz, Ralf Schulz, Hans-Jörg Vogel, Gabriele E. Schaumann |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250150326
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| Publikation (Nr.) |
 EGU/EGU2017-14773.pdf |
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| Zusammenfassung |
| With increasing use of engineered nanoparticles (ENPs) in different commercial products the
risk for their release into the environment is continuously increased. The aging, distribution,
mobility, biological availability, and ecotoxicological impact of ENPs in aquatic and
terrestrial compartments will be influenced especially by the natural dynamics of meadow
areas, which represent a sensible zone between these two compartments. In this study we
present a newly developed floodplain stream mesocosm system linking aquatic and terrestrial
aging of ENPs in one system. Using this system we investigated the distribution, mobility,
and biological effects of silver nanoparticles (Ag NPs) at the aquatic-terrestrial interface.
The mesocosm consists of a main channel, floodplain area, and transport columns
simulating an aquatic compartment with river bed, aquatic-terrestrial transition
zone, and terrestrial area, respectively. The system contained water sampled from
the River Rhine, quartz sand as sediment phase and natural repacked soil from
a Rhine floodplain. Every 3 weeks floodplain area was flooded for four days by
increasing the water level in the main channel. The dispersions of Ag NPs were
injected into the main channel as a pulse function with the pulse duration of 3 weeks
and interval of 3 weeks between pulses. The biological effects of Ag NPs on the
benthic organism Gammarus fossarum were evaluated in the bioassays during and
between the Ag NP pulses. The total duration of the experiment was 33 weeks. The
results of mesocosm experiments showed a fluctuating but successively increasing
concentrations of total silver in the aqueous phase. At the end of the experiment 0.5% of the
silver was still available in the aqueous phase mostly as nanoparticles. Although the
major part of silver was immobilized in sediment and soil especially in their top
layer, the feeding activity of Gammarus fossarum was not consistently affected. It is
most likely due to the low concentrations of silver applied in the experiment and
limited dissolution of Ag NPs. Furthermore, extremely high enrichment factors of
silver were determined for leaves (up to 11000) and algae (up to 30000) suggesting
possible bioaccumulation of silver in aquatic organisms feeding on leaves and algae. |
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