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Continuous-flow generation of plumbane from different media for sample introduction into an inductively coupled plasma (ICP) for the determination of lead by atomic emission spectrometry (AES) was investigated in detail. Different "organized molecular assemblies" (micelies and vesicles) were tried for plumbane generation using the ammonium peroxodisulphate-nitric acid system as oxidant and sodium tetrahydroborate as the reducing agent. Cetyltrimethylammonium bromide (CTAB) or, alternatively, didodecyltrimethylammonium bromide was found to accelerate plumbane generation in the oxidant mixture. The advantages of hydride generation using aqueous, micellar or vesicular media are discussed and critically compared in terms of sensitivity, selectivity and accuracy of the corresponding ICP-AES determination of low levels of lead. The method using ammonium peroxodisulphate-nitric acid-CIAB proved to be superior (detection limit 9 ng ml-' and precision 1.4% at the 50 ng ml-' level) to conventional hydride generation, and was applied to_ the determination of low levels of lead in soft drinks by ICP-AES. Validation of the results was carried out successfully by graphite furnace atomic absorption spectrometry.