  A non-minimal photon-torsion axial coupling in the quantum electrodynamics
(QED) framework is considered. The geometrical optics in Riemannian-Cartan
spacetime is considering and a plane wave expansion of the electromagnetic
vector potential is considered leading to a set of the equations for the ray
congruence. Since we are interested mainly on the torsion effects in this first
report we just consider the Riemann-flat case composed of the Minkowskian
spacetime with torsion. It is also shown that in torsionic de Sitter background
the vacuum polarisation does alter the propagation of individual photons, an
effect which is absent in Riemannian spaces.
