  The effect of spin of particles in the propagation of plasma waves is studied
using a semi-classical kinetic theory for a magnetized plasma. We focus in the
simple damping effects for the electrostatic wave modes besides Landau damping.
Without taking into account more quantum effects than spin contribution to
Vlasov's equation, we show that spin produces a new damping or instability
which is proportional to the zeroth order magnetization of the system. This
correction depends on the electromagnetic part of the wave which is coupled
with the spin vector.
