I reckon damage to the turbo blades could be a real issue, sort of like cavitation damage to a boat propeller. I dealt with a company who made Air Cycle Units (Cold Air Units) with turbines where they were experiencing the intakes being blocked up periodically with plastic bags causing massive RPM surges. They said this was one of the worst things that could happen to turbine blades because it caused fatigue fractures at the blade root. Any such failure of course leads to catastrophic failure because of the extremely high RPM's.