Development and Evaluation of a Nanoparticle Generator for Human Inhalation Studies with Airborne Zinc Oxide |
| |
Authors: | Christian Monsé Christian Monz Dirk Dahmann Christof Asbach Burkhard Stahlmecke Norbert Lichtenstein |
| |
Affiliation: | 1. Institute for Prevention and Occupational Medicine of the German Social Accident Insurance, and Institute of the Ruhr-University Bochum , Bochum , Germany;2. Institute for the Research on Hazardous Substances , Bochum , Germany;3. Institute of Energy and Environmental Technology e.V. , Duisburg , Germany;4. Institute for Occupational Safety and Health of the German Social Accident Insurance , Sankt , Augustin , Germany |
| |
Abstract: | In the EU there is an increasing need for regulatory agencies to derive health based threshold limits based on human inhalation studies with airborne particles. A necessary prerequisite for such projects is the development of a suitable generator system to produce nanoparticle test aerosols for human whole-body inhalation studies. We decided to use a generator with flame-based heating of aqueous precursor solutions. Validation of the test system was done by generating zinc oxide (ZnO) nanoparticles with minimal contamination of trace gases, i.e., nitric oxides or carbon monoxide that could confound the effects seen in exposed subjects. ZnO was selected based on the uncertainties surrounding its health effects after exposure at the workplace. The generation process of the developed flame generator yields ZnO nanoparticles with monomodal size distribution and very good temporal stability. The maximum target exposure mass concentration of 2 mg/m3 ZnO, with a resulting median particle diameter of 57 nm, is attainable in our human exposure laboratory. The morphological examination shows typical agglomerates and aggregates formed by high temperature processes. Overall, the performed experiments confirm that a constant exposure can be provided for all subjects at all times. Copyright 2014 American Association for Aerosol Research |
| |
Keywords: | |
|
|