Determination of particle size distribution of selected aerosol cosmetics

Synopsis Several methods for the determination of particle size distribution of aerosols have been reviewed. The Cascade Impactor was investigated and found suitable for classi-fying the particle size distribution of aerosols between 0.5 and 32.0 u. Various sampling chambers were evaluated and the design of the chamber was found to be an ixnportant factor for particle size distribution. A modified distilling flask proved to be most suitable for this purpose. The particle size distribution of two aerosol hair spray formulations was deter-nilned using this technique. Particles between 0.5 and 32 u were classified with special attention given to those particles below 10 u in diameter. Several valve combinations were studied and evaluated on the basis of the proportion of particles below 10 u. The Cascade Impactor has been shown to be satisfactory for evaluating the toxicological potential of these aerosols based upon particle size distribution and upon other considerations