  Mercury, due to its close location to the Sun, is surrounded by an
environment whose conditions may be considered as "extreme" in the entire Solar
System. Both solar wind and radiation are stronger with respect to other Solar
System bodies, so that their interactions with the planet cause high emission
of material from its surface. Moreover, the meteoritic precipitation plays a
significant role in surface emission processes. This emitted material is
partially lost in space. Although under the present conditions the surface
particles loss rate does not seem to be able to produce significant erosion of
the planetary mass and volume, the long-term effects over billions of years
should be carefully considered to properly understand the evolution of the
planet. In the early stages, under even more extreme conditions, some of these
processes were much more effective in removing material from the planet's
surface. This study attempts to provide a rough estimation of the material loss
rate as a function of time, in order to evaluate whether and how this
environmental effect can be applied to understand the Hermean surface
evolution. We show that the most potentially effective Sun-induced erosion
process in early times is a combination of ion sputtering, photon stimulated
desorption and enhanced diffusion, which could have caused the loss of a
surface layer down to a depth of 20 m, as well as a relevant Na depletion.
