Abstract
An apparatus for production of submicron radiolabeled di-2-ethylhexyl phthalate (DEHP) aerosol was developed for use in experiments involving acute inhalation exposure of small laboratory animals. A new nebulizer, with a low reservoir volume to minimize radiolabel requirements, was tested. Aerosol output from the nebulizer was regulated through changes in the flow rate of DEHP into a constant velocity air stream in the nebulizer body. Under optimum conditions, 90% of the aerosol was less than 1 µm mass median aerodynamic diameter. Concentrations from 20 to 600 mg/m3 were within the operating range of the apparatus. The system offered positive control of nebulizer output, with minimum nebulizer operating pool requirements and should be adaptable to a number of similar compounds.