Dear Carla,
                    It is my understanding that bleach and formalin result in
the formation of chlorine, which as you may know is pretty toxic. It is
however a recommended method of disposing of formalin according to the fine
print in the Federal Register (CFR is it called?) that I read a few years
ago. There are some references I can dig out if you are really interested.

Mike Titford
Pathology
USA Medical Center
Mobile AL 36617