Lead

David Kerr <d.kerr [at] nls__uk> writes

>...  A note has been inserted
>with the package of blocks indicating the metal may contain lead and
>therefore lead oxide may be present.  What precautions should we be
>taking when handling these blocks and are there any recommendations
>that should be followed should Library users wish to look at them.
>Also, the printing blocks haven't been cleaned since they were last
>used with a combination of dried ink and dust on them.  Does anybody
>have any recommendations for cleaning them.

Lead and its corrosion products are toxic if ingested into the body.
Often lead corrosion produces a heavy white or yellowish powdery
substance (lead carbonate?) which easily comes loose. I would
recommend, especially if corrosion exists, wearing disposable gloves
and a disposable dust mask or respirator for handling and a thorough
hand washing when complete.

I believe if the lead is oxidized (black or dark gray in color), the
oxidation layer will actually retard corrosion and produce a stable
barrier layer between the environment and the lead underneath, so
perhaps cleaning isn't necessary. A light vacuuming with a
conservation vacuum (you don't want to circulate any lead particles
into the air) would probably take care of the dust, but any cleaning
may produce lead bearing waste, which may need to be handled as
hazardous.

I hope this helps, and I am sure others more knowledgeable can
correct me or give you more helpful specifics.

Mark D. Hanson, Curator
Octave Chanute Aerospace Museum
1011 Pacesetter Drive
Rantoul IL 61866
USA
217-893-1613


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                  Conservation DistList Instance 18:25
                Distributed: Wednesday, December 1, 2004
                       Message Id: cdl-18-25-008
                                  ***