A model for "breathing" plasmas observed in the large helical device [Y. Ta
keiri , Plasma Phys. Controlled Fusion 42, 147 (2000)] is proposed. It take
s into account the synergism of radiation losses from both low-Z (carbon, o
xygen) and high-Z (iron) impurities in the plasma power balance. (C) 2000 A
merican Institute of Physics. [S1070- 664X(00)01411-7].