Inhalation exposure system for diesel exhaust particulates

Abstract

The objectives of this research were twofold. First, a Hazelton 2000 Inhalation Chamber was modified to minimize the amount of diesel exhaust particulate (DEP) needed for animal inhalation exposures. Second, instrumentation was evaluated for aerosolizing DEP, monitoring the mass concentration and size distribution, and determining the uniformity of the aerosol.;The Jet-O-Mizer jet mill produced a single mode DEP mass median diameter (MMD) of 0.33 mum while maintaining a relatively steady mass concentration of 10 mg/m3. The uniformity of a carbon black aerosol was found to vary from 9.9 mg/m3 in the front part of the chamber, to 10.4 mg/m3 in the center, and 11.7 mg/m 3 in the rear. The Tapered Element Oscillating Microbalance (TEOM) was found to satisfactorily monitor the mass concentration but the filter lifetime at high mass concentrations would necessitate periodic observations.