AAAR 32nd Annual Conference
September 30 - October 4, 2013
Oregon Convention Center
Portland, Oregon, USA
Abstract View
Characterisation of Emitted Particles during Maintenance of Common Nano Particle Generator
Patrik Nilsson, Linus Ludvigsson, Jenny Rissler, Maria E Messing, Christina Isaxon, Axel C. Eriksson, Maria Hedmer, Håkan Tinnerberg, Knut Deppert, ANDERS GUDMUNDSSON, Joakim Pagels, Lund University
Abstract Number: 421 Working Group: Engineered Nanoparticles: Emissions, Transformation and Exposure
Abstract The production of engineered nanoparticles is rapidly growing and measurement and characterization of the particle exposure of the whole manufacturing processes is important to obtain reliable risk assessments. In this work we characterized particle emissions during maintenance of common particle generators: a Spark Discharge Generator and a High Temperature furnace. Both generators were operated upstream a sintering furnace.
Online characterization of as-produced particles was carried out with a Scanning Mobility Particle Sizer and filter sampling for analysis with transmission electron microscopy. During the maintenance sampling was carried out within the expected emission zone using an Aerodynamic Particle Sizer and a Condensation Particle Counter. Filters for scanning electron microscopy analysis were collected. Time-resolved chemical identification was obtained using a Laser Vaporization Aerosol Mass Spectrometer (LV-AMS, Aerodyne Inc.) of both the as-produced and emitted particles.
During maintenance the emissions in terms of particle mass and surface area were dominated by particles larger than1µm. SEM analysis revealed that the particles were highly agglomerated and consisted of both the originally as-produced aggregates and the sintered particles. The chemical identification using LV-AMS of the emitted particles showed that they were dominated by the metal elements used during the particle synthesis sessions prior to the maintenance.
The geometric mean diameter of the as-produced and the emitted particles were ~0.03 µm and ~1.8 µm, respectively, which coincides with the lower and the upper maxima of the pulmonary deposition curve.
This work shows the importance of including measurements of particles larger than1µm in assessments of emissions and exposure to manufactured engineered nanoparticles.
This work was supported by the Consortium for Aerosol Science and Technology, the Nanometer Structure Consortium at Lund University (nmC@LU), the Swedish research council FAS and the FAS-centre METALUND.