[Histonet] Alcohols - clarification - help needed

[Tracy Bergeron]

Hi folks,

        Our lab is trying to trying to change to an alcohol that is less 
harsh on rodent tissue than your typical reagent grade alcohols can be. 
We've considered moving to pure EtOH, but the company we work for is not 
all that keen on dealing with the regulations etc involved with it's use.
        So....  We've been looking at the products offered by 
Pharmco-Aaper and have come across some confusing information, at least to 
me anyway.  Yes I have emailed the sales rep and am waiting for her reply.
        Pure EtOH is listed as 200 proof and anhydrous, 95% EtOH is listed 
as 190 Proof.  When you look at the denatured alcohols you end up seeing 
EtOH mixed with various and sundry solvents like Toluene, unleaded 
gasoline, etc etc.  But where I get stuck is when the spec sheet says that 
the EtOH is 190 proof in toluene, but does not list the water content, yet 
does not say it is anhydrous.  Can we assume that a 190 proof EtOH is 
these cases is the same as 95% EtOH with 5% water?   My assumption is that 
if it doesn't say it is anhydrous then it is not whether the water content 
is listed on the spec sheet or not.

        Have any of you out there used the Aaper denatured alcohols, that 
are not the reagent grade?  Also regarding the pure EtOH that is ACS and 
is a synthetic product, is that regulated by the ATF,  as is grain 
alcohol?  My limited understanding of synthetic vs grain alcohol is that 
the synthetic is not used in food products - and I don't think it is 
drinkable, but I could be wrong.  Any ides on this.

Thanks.

Sincerely,
Tracy E. Bergeron, B.S., HT, HTL (ASCP)
Associate Scientist III, Pathology
Comparative Pathology Laboratory
Biogen Idec
14 Cambridge Center
Cambridge, MA 02142
Direct:  617-914-1115
Fax:  617-679-3208