Arsenic in silked documents

We have recently become involved in a series of large manuscript and
printed document projects which involve silked papers. In doing
preliminary research we have learned that one of the silking pastes
typically used in North America earlier in the 20th century
contained arsenic, presumably as a biocide. This recipe is published
in J.C.Fitzpatrick, "Notes on the Care, cataloguing, Calendaring,
and Arranging of Manuscripts", U.S.Government Printing Office, 1913
and 1928 (3rd edition). The safety of conservators, curators and
readers handling these materials concerns us and we have been using
instrumental analysis (XRF) to screen silked collections for the
presence of arsenic. Has anyone explored the use of microchemical
tests to screen these materials where the amount of arsenic is
presumably quite low?

Thea Burns
Priscilla Anderson
Weissman Preservation Center
Harvard University Library


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                  Conservation DistList Instance 17:70
                   Distributed: Sunday, May 23, 2004
                       Message Id: cdl-17-70-019
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