The reactions resulting in the tritium contamination of mineral oils in pumps during transfer of tritium-containing gas mixtures are examined. The basic chemical forms of tritium dissolved in oils are established. The adsorption of tritium-containing impurities of spent oils and the chemical isotopic exchange of adsorbed impurities with concentrated sulfuric acid are studied. A method for handling tritium-containing waste oils that permits decreasing the radiation hazard due to storage of these oils and recycling tritium gas is proposed on the basis of these investigations.