[en] A method is described for the introduction of tritium into organic compounds by substituting tritium for halogen, the so-called solid-state catalytic reductive dehalogenation (SSCRD). The dependence of the yield of final products on the reaction conditions was studied. It is found that, at a certain catalyst/halogen derivative ratio, the yield of the labelled products is practically quantitative. The SSCRD technique was used for the preparation of various tritium-labelled components of nucleic acids with specific activities up to 20 Ci/mM