  It is proposed to employ the P,T-odd Faraday effect, i.e. rotation of the
polarization plane of the light propagating through a medium in presence of the
electric field, as a tool for observation of P,T-odd effects caused by CP
violation within the Standard Model. For this purpose the vapors of heavy atoms
like Tl, Pb, Bi are most suitable. Estimates within the Standard Model show:
provided that applied field is about 10^5 V/cm and the optical length can be as
large as 70000 km, the rotation angle may reach the value corresponding to the
recently observable values (10^{-9} rad). These estimates demonstrate that the
P,T-odd Faraday effect observations may effectively compete with the recent
measurements of the electron spin rotation in an external electric field,
performed with diatomic molecules. These measurements exclude the P,T-odd
effects at the level 9 orders of magnitude higher than the predictions of the
Standard Model.
