Yes, as everyone has pointed out ITX is not the same as bismuth. And as Oskar also pointed out, ITX is like most other non-toxic shot these days, in that it contains powdered tungsten. This will be abrasive to your barrel if not properly contained within a plastic shotcup. The type of abrasion encountered is not what some have experienced with other types of hard shot (i.e. steel shot).
The damage caused will not be visible scratches running down your barrel. Think of it more like spraying ultra fine sandblaster grit down your barrels. Visually, it would be almost impossible to tell without measuring changes in dimensions, especially at the chokes.
Again, all of this is a moot point if you simply use plastic shot cups to protect your barrel. In a previous thread the OP asked about using simple card wads and black powder with ITX shot. This should be avoided if you plan on putting a lot of rounds though the gun.