Production of Relatively Monodisperse Aerosols for Inhalation Experiments by Aerosol Centrifugation

Abstract

Stober's aerosol spectrometer, based on a spinning spiral duct, was used as an aerosol centrifuge to separate narrow size groups of insoluble aerosols starting from polydisperse distributions. The samples collected were resuspended in water and aerosolized with a Lovelace nebulizer to produce relatively monodisperse aerosols. Working with near-spherical fused clay particles, aerosols were obtained with geometric standard deviations of less than 1.1 and with number concentrations which would be practical for use in inhalation experiments. A formula for dilution of monodisperse suspensions for aerosolization was used to calculate the maximum number concentration that could be aerosolized from a suspension for a particular nebulizer, to obtain 95 % singlets. This method appears to be particularly adaptable for the aerosols of oxides of transuranic elements. Estimated respiratory depositions of the oxides of 239Pu, 238Pu, 244Cm and 241Am for Beagle dogs breathing the monodisperse aerosols for 1 hr are given for aerodynamic sizes ranging from 0.5 μm to 3.0 μm.