Nitroso R salt and potassium ferricyanide, in hydrochloric acid, have been used as the reaction medium for simultaneous generation of arsine and plumbane, combined with inductively coupled plasma-atomic emission spectrometric detection. Both of the reagents enhance the lead signal and neither reagent inhibits the arsenic signal, provided that the potassium ferricyanide is mixed on-line with the analyte solution. Potassium iodide, which is used to prereduce As(V) to As(III), does not interfere with plumbane generation in both reaction systems. Various parameters affecting the signals have been studied, and the hydrochloric acid-potassium ferricyanide system has proved to be a better reaction medium. Detection limits of lead and arsenic are 1.1 and 2.8 ng/ml, respectively, have been obtained in the HClK(3) Fe(CN)(6) system at a sample uptake rate of 1.5 ml/min.