quantification and detection of low ng levels of metal oxides. For example, a detection limit of ca. 0.34 ng/L (PbO), 0.28 ng/L (CdO) and 0.30 ng/L (CuO) was estimated on the basis of the signal-to-noise characteristics (S=N.3) of the response for a 1 ng/L metal oxide particulate samples following a 2 min accumulation. Even lower concentrations can be detected in connection to longer deposition periods.