Jeremy,
 
I can't vouch for the blindness.  I know that it is entirely possible with
Formic.  It's nasty stuff and should be used very carefully if at all.  It
doesn't cause the itchy burning sensation that you might associate with an
"acid" so you could have skin contact and not really realize it. I've lost a
few layers of skin on my hands and wrist before due to contact with 65%
solution.  Accidents happen no matter how careful one might be.  What I would
like you to consider is the damage to lung and sinus tissue by those that
refuse to wear respirators.  The vapors are awful and the wind always changes
directions.  It may be a fabulous chemical but I think the draw backs
outweigh the benefits.
 
Brian Tassey
Kaykin @aol.com