Its not surprising to me that oxalic acid could be damaging the kidney
functions of bees since it is well known that the main component of
anti-freeze, ethylene glycol is extremely toxic to humans because it is
metabolized to oxalic acid which then shuts down kidney function sometimes
permanently and the person needs dialysis to stay alive.  An acquaintance of
mine accidentally swallowed a small amount of antifreeze by attempting to
start the siphoning off of the antifreeze in a car radiator.  He was in the
hospital, a very sick man for several weeks and eventually his kidney
function came back and he was taken off dialysis again.  (See the following
URL for toxic effects of ethylene glycol and oxalic acid:
http://www.vet.uga.edu/vpp/clerk/Torres/index.php   and also: 
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?itool=abstractplus&db=
pubmed&cmd=Retrieve&dopt=abstractplus&list_uids=16417036

Ed Geels

******************************************************
* Full guidelines for BEE-L posting are at:          *
* http://www.honeybeeworld.com/bee-l/guidelines.htm  *
******************************************************