  Chandra X-Ray Observatory (CXO) ACIS-S spectra of three quasars which lie
behind three foreground damped Lyman alpha (DLA) absorbers are analyzed in
order to attempt to determine the amount of photoelectric absorption due to
metals present in their x-ray spectra. These absorbers are the three largest
neutral hydrogen column density absorption-line systems known at low redshift
(0.313 \le z_abs \le 0.524). They have HI column densities which lie between
3E21 and 5E21 atoms/cm^2. At these redshifts the amount of photoelectric
absorption at x-ray energies is primarily an indicator of the oxygen abundance.
Since the column densities of these systems are so high, one would expect
accurate metallicity measurements of them to yield a robust estimate of the
column-density-weighted cosmic neutral-gas-phase metallicity at z \approx 0.4.
We consider cases where the DLA gas has solar element abundance ratios and ones
with the alpha-group element abundance ratios enhanced. For the adopted
assumptions, the column-density-weighted cosmic neutral-gas-phase metallicity
of the non-enhanced elements (e.g. Zn) at z \approx 0.4 likely lies in the
range \approx 0.04-0.38 Z_solar.
