Cleaning lead type

I have had an enquiry about cleaning lead type.  The person
concerned is concerned about the toxicity inherent in any process
that involves lead.  Would anyone with experience in this area be
able to respond directly?

Most of the type is lightly encrusted with lead oxide, plus a
hundred years of ordinary dirt and remnants of printing ink.  He was
considering:

    A rinse in soapy water to loosen the dirt

    A soak in an organic solvent--a dilute solution of citrus paint
    stripper, N-Methyl Pyrrolidone, which is completely
    water-miscible, to loosen the ink

    A soak in 5% acetic acid to dissolve the majority of the lead
    oxide followed by some time in an ultrasonic bath to finish the
    job

He also had a couple of questions:

Do you think this set of actions will do the job and bearing in mind
the toxicity issues is it safe for me and for the type?

Should the solution in the ultrasonic bath consist of plain
(distilled, perhaps?) water, or is there a better alternative?

Alayne Alvis
Conservator
Sydney University Museums
Room H102, Quad A14
The University of Sydney
NSW 2006
+61 2 9351 2761
Fax: +61 2 9351 2881


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                  Conservation DistList Instance 27:30
                Distributed: Wednesday, January 29, 2014
                       Message Id: cdl-27-30-026
                                  ***