  We show that the presence of parity-odd terms in the conductivity (or, in
other words, in the polarization tensor of Dirac quasiparticles in graphene)
leads to rotation of polarization of the electromagnetic waves passing through
suspended samples of graphene. Parity-odd Chern-Simons type contributions
appear in external magnetic field, giving rise to a quantum Faraday effect
(though other sources of parity-odd effects may also be discussed). The
estimated order of the effect is well above the sensitivity limits of modern
optical instruments.
