  The one--loop contribution of the two CP--violating components of the
$WW\gamma$ vertex, $ \tilde{\kappa}_\gamma W^+_\mu W^-_\nu \tilde{F}^{\mu \nu}$
and $(\tilde{\lambda}_\gamma / m^2_W)W^+_{\mu \nu}W^{-\nu}_{\
\rho}\tilde{F}^{\rho \mu}$, on the electric dipole moment (EDM) of fermions is
calculated using dimensional regularization and its impact at low energies
reexamined in the light of the decoupling theorem. The Ward identities
satisfied by these couplings are derived by adopting a $SU_L(2)\times
U_Y(1)$--invariant approach and their implications in radiative corrections
discussed. Previous results on $\tilde{\kappa}_\gamma$, whose bound is updated
to $|\tilde{\kappa}_\gamma| <5.2\times 10^{-5}$, are reproduced, but
disagreement with those existing for $\tilde{\lambda}_\gamma$ is found. In
particular, the upper bound $|\tilde{\lambda}_\gamma|<1.9\times10^{-2}$ is
found from the limit on the neutron EDM, which is more than 2 orders of
magnitude less stringent than that of previous results. It is argued that this
difference between the $\tilde{\kappa}_\gamma$ and $\tilde{\lambda}_\gamma$
bounds is the one that might be expected in accordance with the decoupling
theorem. This argument is reinforced by analyzing careful the low--energy
behavior of the loop functions. The upper bounds on the $W$ EDM,
$|d_W|<6.2\times 10^{-21} e\cdot cm$, and the magnetic quadrupole moment,
$|\tilde{Q}_W|<3\times 10^{-36} e\cdot cm^2$, are derived. The EDM of the
second and third families of quarks and charged leptons are estimated. In
particular, EDM as large as $ 10^{-20} e\cdot cm$ and $10^{-21} e\cdot cm$ are
found for the $t$ and $b$ quarks, respectively.
