Assessment and Characterization of Exposures to Airborne Nanoparticles Associate with Typical Industrial Processes
S-J Tsai, C. Barry, M.J. Ellenbecker
University of Massachusetts Lowell, US
Keywords: nanoparticle, exposure, airborne nanoparticle, particle sampling
Abstract:Engineered nanoparticles are being manufactured and used at a dramatically increasing rate while the risk assessments for nanoparticle exposures are incomplete. As part of ongoing efforts for the respiratory protection of researchers in the Center for High-rate Nanomanufacturing (CHN), nanoparticle exposure levels in various nanoparticle research laboratories were measured during various operations that process and handle solid nanoparticles including synthesis of carbon nanotubes, nanocomposite compounding, etc. Breathing zone particle number concentrations and particle size distributions were not significantly different from those of background when the process or handling was performed inside a laboratory fume hood or an effective local exhaust hood. A TSI Fast Mobility Particle Sizer (FMPS) was used to measure airborne particle concentration from 5 nm to 560 nm in 32 size channels. Air samples were also collected on TEM grids placed on polycarbonate membrane filters and particles were characterized by transmission electron microscopy and scanning electron microscopy. Airborne particle concentrations measured at breathing zone locations were analyzed to characterize the personal exposure level. Elevated concentrations at the source location compared to the background concentration were found in most laboratories.