"(especially with the primer lead dust scare currently going on). "
Yeah, and it's a shame; there's no meaningful lead involved with tumbling. Seems some guys with the "you can't be too careful" mindset are playing Chickin' Little. The 'horrid gray dust' they seem frightened by is the polish, not lead. It's the same type polish you apply to your car from time to time and it's no more harmful. Don't work to inhale the dust - because it IS dust - and don't lick your fingers clean of the gray dust and all will be well.