A method in which a cascade impactor is interfaced directly to an atomic absorption system to allow measurements of the masses of analyte associated with various droplet sizes is described. Data are presented which indicate that this measurement approach conveniently provides results equivalent to those obtained by the indirect protocol used by others [see M. S. Cresser and R. F. Browner, Spectrochim, Acta 35B, 73 (1980)] when a filter is used to collect the analyte transported through the impactor. In addition to saving analysis time while providing reliable results, the method is shown to prevent positive size measurement biases due to failure to collect aerosol not trapped by an impactor.
