A new interpretation of the in situ TRIO experiment on tritium release from γ-LiAlO2 ceramic particles is presented. It is suggested that, due to a very small ceramic particle radius (R = 0.1 µm), the release-controlling phenomenon is desorption of tritium-containing molecules from the particle surface rather than tritium diffusivity in the particle. This hypothesis eliminates the large discrepancy with previous tritium diffusivity experiments with large particles, where the time-controlling phenomenon is clearly diffusivity.