Just a thought, while I would not feel qualified to give advice on object care, in the past, somewhat stale bread, french, not whole wheat, was a material commonly used by people, who took care of art, to lightly clean a variety of objects. If a good rule for a conservator, as for a doctor, is first do no harm, it seems a pretty risk free way to "dust", strictly a physical process as opposed to a chemical one. There are large numbers of sound paintings that illustrate practices of the past were not all harmful. I wonder what shape 20th century paintings will be in 500 years from now, not that it will be of any personal interest. I suspect in the dark corners of European labs there is still a loaf or two lurking about. When all is said and done conservation is still more of an art than a science.