  Chandra high-resolution spectra toward eight low-mass Galactic binaries have
been analyzed with a photoionization model that is capable of determining the
physical state of the interstellar medium. Particular attention is given to the
accuracy of the atomic data. Hydrogen column densities are derived with a
broadband fit that takes into account pileup effects, and in general are in
good agreement with previous results. The dominant features in the oxygen-edge
region are O I and O II K$\alpha$ absorption lines whose simultaneous fits lead
to average values of the ionization parameter of $\log\xi=-2.90$ and oxygen
abundance of $A_{\rm O}=0.70$. The latter is relative to the standard by
Grevesse & Sauval (1998), but a rescaling with the revision by Asplund et al.
(2009) would lead to an average abundance value fairly close to solar. The low
average oxygen column density ($N_{\rm O}=9.2 \times 10^{17}$ cm$^{-2}$)
suggests a correlation with the low ionization parameters, the latter also
being in evidence in the column density ratios OII/OI and OIII/OI that are
estimated to be less than 0.1. We do not find conclusive evidence for
absorption by any other compound but atomic oxygen.
