2002 Volvo S80 T6 Turbine smoke?

My 2002 Volvo S80 emits a plume of white smoke after running a few minutes then it clears up. Volvo serviceman said it was nothing to worry about; something to do with turbines, humidity and catalytic converter. What gives? (Has 128,000 miles)

Its possible the seal that keeps coolant outside the interior of the turbo is giving up.

Thank you.