After quoting from
Determination of oxalic acid and other organic acids in honey and in some 
anatomic structures of bees by
María Jesús NOZAL, José Luis BERNAL, Luis Antonio GÓMEZ,Mariano HIGESb, 
Aranzazu MEANA

> " After topical administration ,there is an interval of time in which the 
> oa
> concentration in internal organs of the bee increases. This demonstrates
> that,when hives are treated against varroa ,oa penetrates through the bee
> Keratin and can produce the toxic effect"
> Bob said
> The above toxic effect means to me toxic to the varroa.

I don't think it is necessarily so , they are talking about BEE KERATIN so I 
presume they must mean the toxic effects of oxalic acid on bees.

Ruary 

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