The potentialities of an in situ radiotracer technique based on the measurement of X-radiation induced by beta-particles are analysed. It is shown that the proposed method can be applied in cases when the direct measurement of beta-radiation is not possible (eg using thick electrodes or when the energy of the beta-radiation is low). The application of the method for the study of surface processes is demonstrated in connection with sorption and desorption studies on austenitic stainless steel using S-35, P-32 and Tc-99 labelled sulphate, phosphate and pertechnetate species.