  The standard model $SU(2)_L\times U(1)_Y$ gauging of the Wess-Zumino-Witten
term requires a modified counterterm when background fields, needed to generate
the full set of currents, are introduced. The modified counterterm plays an
essential role in properly defining covariant global currents and their
anomalies. For example, it is required in order to correctly derive the gauge
invariant baryon number current and its anomalous divergence. The background
fields can also be promoted to a description of the physical spin-1 vector and
axial-vector mesons in QCD and the counterterm leads to novel interactions.
These are (pseudo-) Chern-Simons terms, such as $\epsilon^{\mu\nu\rho\sigma}
\omega_\mu Z_\nu \partial_\rho A_\sigma$ and $\epsilon^{\mu\nu\rho\sigma}
\rho^{\pm}_\mu W^{\mp}_\nu \partial_\rho A_\sigma$ that mediate new
interactions between neutrinos and photons at finite baryon density.
