Determination of lead by hydride generation atomic absorption spectrometry in the presence of nitroso-R salt

A method is described for the determination of lead by hydride generation atomic absorption spectrometry in the presence of nitroso-R salt (1-nitroso-2-naphthol-3,6-disulphonic acid, disodium salt). The method is superior in sensitivity to those using peroxodisulphate, dichromate or hydrogen peroxide as oxidants. A characteristic concentration (0.0044 absorbance) of 0.8 ng ml^?1 and a relative standard deviation of 3.8% for 20 ng ml^?1 Pb were obtained. The proposed method has been applied successfully to the determination of lead in certified reference materials.