In general 8 years is not very long on the shelf for many of the dyes 
you mention as long as they stay dry. I have been known to comb the 
dustiest of shelves in search of Congo Red lots from the fifties (they 
have a higer due content than anything you can buy now). Hematoxylin 
will also last for just about ever. As for testing, chemical and 
empirical tests for most common dyes are in "Conn's Biological 
Stains'" If you run across a jar of picric acid that has been around 
a long time, don't touch it, stop rummaging completely. Get some 
professional hazardous waste folks to help you out.

Bert Dotson

On Sun, 08 Aug 1999 19:22:53 -0600 "William E. James Jr. H.T. A.S.C.P." 
<w.e.jmesjr.@worldnet.att.net> wrote:

> Hello,
>         I am looking for any info on the shelf life of reagents in dry
> form.
> ie: Eosin y, Hematoxylin, Congo Red, etc.
> 
>         Will they last for more than 10-15 years and is there any way to
> test
> them for use.
> 
>         I just started in the lab here at AML in Louisiana and the
> reagents
> here date back to 85 and in most cases none are less than 8 yeas old.
>                                                         thanx
>                                                 W.E.James Jr. H.T.
> 

----------------------
Bert Dotson
amdj@duke.edu