In the document, a method for the determination of metallic impurities in U or Pu containing solutions (or samples which can be dissolved) is described. Inductive heating of a carrier gas such as argon in a coil to very high temperatures produces a plasma, in which the sample becomes ionized and excited. Wavelength and intensity of the emitted optical radiation is analyzed. From the intensity of such element specific emission lines, the concentration of impurity elements can be determined.#,,#