Measurements of energetic particle losses from the plasma, in particular alpha particles, remain difficult in large fusion devices and further R&D is needed in view of ITER. The present paper describes new measurements using activation technique. Samples are activated due to nuclear reactions of type (X, n), (X, g), ... where X is a light charged particle p, t, d, 3He and a. After plasma exposure, samples are removed from the sample holder and analysis of samples is performed using high counting efficiency, ultra low-level and high energy resolution gamma-ray spectrometry.