Richard, When I was at the Detroit Institute of Arts we came across the same problem. It was either talc or oil! You could try contacting Terry Birkett, the Collections Manager, I believe he has invesitgateds sources for "clean" plastic. I don't hink he's on email. But call him, 313 833 7900. Good luck. Suzanne ************ Suzanne Quigley Head Registrar, Collections and Exhibitions Solomon R. Guggenheim Museum 1071 Fifth Avenue New York, NY 10128 212 423 3568 fax: 212 423 3650 email: [log in to unmask]