Das NanoFate-Modell beurteilt das Risiko von künstlich hergestellten Nanomaterialien in der Umwelt
Zwar gibt es zurzeit keine Beweise, dass künstlich hergestellte Nanomaterialien eine bedeutende Bedrohung für die Umwelt sind. Jedoch bestehen noch viele Wissenslücken, besonders im Bereich der Ökotoxizität. Der Mangel an Beweisen bedeutet jedoch nicht, dass keine ökologischen Schäden entstehen könnten. Forscher an der Universität von Kalifornien, Santa Barbara, haben ein dynamisches Multikompartiment-Stoffausbreitungsmodell (NanoFate, nicht zu verwechseln mit dem europäischen NanoFATE-Projekt) entwickelt, um die zeitabhängige Akkumulation von künstlich hergestellten Metall-Nanomaterialien in Umweltmedien vorhersagen zu können.
Compared to previous ENM fate models such as MendNano and SimpleBox4Nano, nanoFate considers a wider range of ENM processes, including emissions to air, water (freshwater and marine), and soils (urban, agricultural, undeveloped) from their manufacturing, use, and disposal; advection in and out of main environmental compartments; rate-limited transport across compartments; resuspension to air and attachment to aerosols; transformation into other ENMs or compounds; in natural waters aggregation, sedimentation, dissolution, filtration, and sorption to suspended particles and the subsequent deposition to sediment.
Since some ENMs also dissolve over time, nanoFate accounts for long-term accumulation of both nanoparticles and dissolved metal ions. nanoFate is also designed to allow for the inclusion of other key transformations processes (e.g., oxidation, sulfidation, adsorption of natural organic matter, loss of the original coating) that alter their chemical properties and environmental behavior, though these are not yet sufficiently understood to incorporate into a mathematical model.
nanoFate has been presented in a recent paper in Environmental Science & Technology ("Assessing the Risk of Engineered Nanomaterials in the Environment: Development and Application of the nanoFate Model").
As the researchers write in their paper, nanoFate is unique because of
1) the type and structural detail of compartments included;
2) the inclusion of key fate processes, discussed above, that have not previously been considered collectively in one model; and
3) the approach taken to calculate fate and transport rates in the face of limited data and mechanistic uncertainty.
In addition, because of the rapid progress being made in ENM production and applications, they explore a range of release scenarios and corresponding longterm [ENM] estimates.
nanoFate will be publically available and has been developed with extensibility to other environments, ENMs, and for additional processes.
Quelle: nanowerk