  A necessary first step for dust removal in protoplanetary disc winds is the
delivery of dust from the disc to the wind. In the case of ionized winds, the
disc and wind are sharply delineated by a narrow ionization front where the gas
density and temperature vary by more than an order of magnitude. Using a novel
method that is able to model the transport of dust across the ionization front
in the presence of disc turbulence, we revisit the problem of dust delivery.
Our results show that the delivery of dust to the wind is determined by the
vertical gas flow through the disc induced by the mass loss, rather than
turbulent diffusion (unless the turbulence is strong, i.e. $\alpha \gtrsim
0.01$). Using these results we provide a simple relation between the maximum
size of particle that can be delivered to the wind and the local mass-loss rate
per unit area from the wind. This relation is independent of the physical
origin of the wind and predicts typical sizes in the 0.01 -- $1\,\mu m$ range
for EUV or X-ray driven winds. These values are a factor $\sim 10$ smaller than
those obtained when considering only whether the wind is able to carry away the
grains.
