Kerry Clark wrote:
 
>   The explanation I heard is that the propolis had been processed from
>   "hive scrapings" which had bits of old (lead bearing) paint in them.
 
I wonder if the source of lead in Chinese propolis might be something like fresh
glazier's putty?  This used to be made from lead oxides, with linseed oil mixed
in (I suspect we're using synthetic polymers exclusively in the US today), and
bees might regard it as the same sort of composition as tree saps and gums.
 
John E. Taylor III     W3ZID     | "The opinions expressed are those of the
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