Program: NanoNature: Nanotechnologies for environmental protection - benefits and effects
Project term: 2009 to 2012
Nanotechnology is regarded as a new key technology because of its enormous potential to trigger profound changes in industry, economy and society. The opportunities of nanotechnology are discussed and researched extensively. However, the discussion about the associated risks with regard to the mobility of substances in the environment is only at the beginning. So far there have been few studies on the release, spread and mobility of synthetic nanomaterials in the environment - especially in the subterranean environment - although a number of nanoproducts have been used in everyday life for years. TiO2 nanoparticles are used in sun creams or as a diffusion protection layer in PET bottles and food packaging. At the same time, however, it is also known that synthetic nanoparticles sometimes have harmful effects on the human body and the environment. For example, nanoparticles can penetrate cell membranes relatively easily and penetrate the olfactory centre of the brain through inhalation through the nose, where they have a pathogenic effect. The negative effect of fullerenes (C60) on the brain has been demonstrated in perch.
The aim of the project is to investigate the impact of synthetic nanoparticles on the environment. The focus is on the behaviour and effect of materials and products with functional nanomaterials in soil and groundwater. Basic techniques and standard test methods for the determination of relevant mechanisms and thresholds of action with regard to the mobility of nanomaterials in unsaturated, partially and fully saturated substrates will be developed. The dependence on the composition of the substrate and the interaction with the type of nanoparticles as well as the dependence of the particle size is investigated.
Established laboratory test methods and lysimeters from engineering and hydrogeology and related natural sciences are adapted and used for this purpose. From the test results, laws focusing on the transport properties of the nanoparticles used are derived or the transferability of existing transport laws of colloidal transport as a function of the compartment is investigated or checked. In the next step, the derived laws are summarized in mathematical models in order to be able to predict the spread of synthetic nanoparticles in water-saturated and unsaturated substrates and to carry out scientifically sound risk assessments. Furthermore, the influence of synthetic nanoparticles on soils and in particular with regard to soil retention against pollutants is the focus of the investigation.
The investigations of the project partners take place on samples with the same composition in order to be able to combine the results of the individual investigations and thus all individual processes can be combined in a mathematical model. The materials used are various inert materials, material mixtures and two native soils with a defined mineralogical composition. Furthermore, materials with increasing reactivity in terms of surface size and surface charge are used to extend the fundamentals of particle mobility to such media.
Dispersible fullerols (C60Hn) with C-14 signature for simple concentration determination, nanotubes (MWCNTs), fluorescent silica particles of different sizes, titanium dioxide particles and boehmite particles with different diameters are also provided as particles. The selection has been made in such a way that, in addition to application relevance in industry and technology, a certain particle size spectrum is also examined. Particle analysis is mainly performed by flux field-flow fractionation (FFF). Other examination methods include SEM and TEM images as well as measurements using small angle X-ray scattering (SAXS) and Zetasizer measurements.