> Will the use of aluminum trays 
> combined with the acid of the vinegar
> subject the bees to more aluminum 
> than is good for them?

>> I would also doubt that vinegar is a 
>> concentrated enough acid to pull any
>> appreciable amount of aluminum off a pan

I doubt it was the aluminum itself that was the problem that resulted in the
warning.
It was likely el-cheapo aluminum-magnesium alloy pans

There was also a lot of galvanized metal decades ago.
Galvanized anything has lots of zinc.  

The acetic acid in vinegar of just about any strength will corrode
magnesium, iron, and zinc.  Aluminum is self-passivating in air at room
temp, forming its own handy acid-resistant film of aluminum oxide.  So, if
you had a real aluminum pan, with no surface treatment, the acid would do
nothing at all to the aluminum oxide, or the underlying aluminum.   Anodized
Aluminum is another possible option that would not corrode when subjected to
acid, as the natural passivation is enhanced by anodizing, and the layer of
aluminum oxide would be far too thick to defeat with less than phosphoric
acid, heat, and considerable patience.

So, was it the aluminum?  I don't zinc so.
And if you have those cheap aluminum-magnesium pans, let this galvanize you
into action - toss 'em!

(Can you tell from the wee hour and the bad puns that I'm sitting here
waiting for someone to duct-tape the starboard wing back onto the plane so
we can all go home?)

             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html