I hope someone out there can answer these questions.  I have come
across a piece in our costume collection that had been previously
labelled "Do Not Touch - Treated With Lead."  It is a one-piece dark
purple silk velvet dress that appears to date to the 1880s and is in
remarkably good condition.

During the late 19th and early 20th centuries almost all silk fabrics
were treated with metallic salts, including lead, to provide weight
and the desired rustle.  My questions are; do any, or all, of these
types of garments present some health hazard?  At what point might
the lead become airborne and therefore dangerous?  Exactly how was
the lead or other metallic salt applied to the fabric?  How can an
item be tested to determine if it is hazardous?  Any information
would be greatly appreciated.  TIA.