Modelling nanomaterials in the environment


In order to be able to realistically assess the risks of nanomaterials, it is important to know in what quantities, where and in what form nanomaterials occur in the environment. Together with ETH Zurich, Bernd Nowack and his team developed computer-based models that can be used to assess the concentration and behaviour of different nanomaterials.

Background (completed research project)

The risks and potential toxic effects of artificially produced nanomaterials on organisms and ecosystems is a topic that is hotly debated by authorities and scientists. Before the start of NRP 64, there was a lack of measuring methods or data that could be used to estimate the concentration and behaviour of nanomaterials in the environment and to estimate the potential risk based on evidence. In Bernd Nowack’s project, computer models were developed to simulate the mass flows of six important nanomaterials (nano-silver, nano-titanium dioxide, nano-zinc oxide, carbon nanotubes, fullerenes and nano-gold). The computer model uses production volumes and use of nanomaterials in Switzerland and the EU. It makes it possible to estimate the amounts of nanomaterials that are, were and will be released into the environment. The behaviour of nanomaterials in the environment - their mobility, possible conversion processes and reactions with other substances - is the second important factor that determines the potential risk of nanomaterials. In collaboration with the ETH Zurich, Bernd Nowack’s team developed another model to simulate the behaviour of nanomaterials in the environment. The combination of this model with data on the potential hazards from ecotoxicological research establishes an evidence-based assessment of the risks of nanomaterials for the environment.


Using their computer models, the scientists were able to realistically simulate concentrations of nanomaterials in the environment. They showed that the estimated concentrations of these nanomaterials in wastewater, surface water, sediments and treated sewage sludge are many times lower than the concentrations of conventional materials. Furthermore, they were also able to show that the nanomaterials very quickly bind to natural suspended solids in the wastewater and are thus efficiently removed from the water. In addition, the study confirms that nanomaterials accumulate in sediments. The combination of the mass flow model and the behavioural model made it possible to calculate current concentrations and the persistence of nanomaterials in all major rivers in Switzerland.


The computer models developed in this project provide realistic data on the concentration and persistence of nanoparticles in the environment. The data form a sound starting point for assessing the possible toxic effects of nanomaterials on living organisms, and are thus an essential basis for authorities and scientists to objectively analyse the risks presented by nanomaterials.

Original title

Mass flow analysis and environmental risk assessment of nanomaterials

Project leader(s)

  • Prof. Bernd Nowack


  • Prof. Konrad Hungerbühler
  • Dr. Martin Scheringer



Further information on this content


Prof. Bernd Nowack Eidg. Materialprüfungs- und Forschungsanstalt EMPA Lerchenfeldstrasse 5
9014 St. Gallen +41 71 274 76 82